Cerebellar mutism

Cerebellar mutism

Incidence of cerebellar mutism: 11–29% of children following surgery for cerebellar tumor2) including cerebellar medulloblastoma (53%), posterior fossa ependymoma (33%) & cerebellar pilocytic astrocytoma (11%) 3).

It has also been reported in both children and adults following several other cerebellar insults, including vascular events, infections, and trauma 4).

The uncertain etiology of PFS, myriad of cited risk factors and therapeutic challenges make this phenomenon an elusive entity.

Cerebellar mutism is a rare occurrence following paediatric trauma 5) 6) 7) 8). , this phenomenon has rarely been reported following other insults, such as trauma, and its pathophysiology remains poorly understood.

A seven-year-old child who presented to the casualty department of Sultan Qaboos University Hospital in Muscat, Oman, in May 2013 with a traumatic right cerebellar contusion. The child presented with clinical features of cerebellar mutism but underwent a rapid and spontaneous recovery 9).

The pathogenic mechanism is likely due to the damage occurring to the proximal efferent cerebellar pathway, including the dentate nucleus, the superior cerebellar peduncle, and its decussation in the mesencephalic tegmentum 10).

Superior and inferior cerebellar peduncles and the superior part of the cerebellum were related to CMS, especially the right side 11).

This syndrome involves a variety of signs and symptoms including cerebellar mutism or speech disturbances, dysphagia, decreased motor movement, cranial nerve palsy and, emotional lability. These signs and symptoms develop from an average range of 24 to 107 hours after surgery and may take weeks to months to resolve.

Multi-inflow time arterial spin-labeling shows promise as a noninvasive tool to evaluate cerebral perfusion in the setting of pediatric obstructive hydrocephalus and demonstrates increased CBF following the resolution of cerebellar mutism syndrome 12).

The importance of olivary hypertrophic degeneration as a differential diagnosis in cerebellar mutism syndrome 13).

Early recognition of this syndrome could facilitate preventive and restorative patient care, prevent subsequent complications, decrease length of hospital stays, and promote patient and family understanding of and coping with the syndrome 14).

20 cases of PFS (8%), 12 males and 8 females. Age ranged from 1.5 to 13 years (mean = 6.5). Of the 20, 16 were medulloblastoma, 3 ependymoma and 1 astrocytoma. There was a 21 % incidence (16/76) of PFS in medulloblastoma of the posterior fossa. The incidence for ependymoma was 13% (3/24) and 1% (1/102) for astrocytoma. All 20 cases (100%) had brainstem involvement by the tumor. The most frequent postoperative findings included mutism, ataxia, 6th and 7th nerve palsies and hemiparesis. Mutism had a latency range of 1-7 days (mean = 1.7) and a duration of 6-365 days (mean = 69.2, median = 35). Although mutism resolved in all cases, the remaining neurologic complications which characterized our findings of PFS were rarely reversible. We describe potential risk factors for developing PFS after surgery with hopes of making neurosurgeons more aware of potential problems following the removal of lesions in this area. Early recognition of PFS would further promote patient and family understanding and coping with this síndrome 15)


19 children diagnosed with posterior fossa syndrome 16)


1)

Rekate HL, Grubb RL, Aram DM, Hahn JF, Ratcheson RA. Muteness of cerebellar origin. Arch Neurol. 1985;42:697–8. doi: 10.1001/archneur.1985.04060070091023.
2)

Gudrunardottir T, Sehested A, Juhler M, et al. Cerebellar mutism: review of the literature. Childs Nerv Syst. 2011; 27:355–363
3)

Catsman-Berrevoets C E, Van Dongen HR, Mulder PG, et al. Tumour type and size are high risk factors for the syndrome of “cerebellar” mutism and subsequent dysarthria. J Neurol Neurosurg Psychiatry. 1999; 67:755–757
4)

Gudrunardottir T, Sehested A, Juhler M, Schmiegelow K. Cerebellar mutism: Review of the literature. Childs Nerv Syst. 2011;27:355–63. doi: 10.1007/s00381-010-1328-2.
5)

Erşahin Y, Mutluer S, Saydam S, Barçin E. Cerebellar mutism: Report of two unusual cases and review of the literature. Clin Neurol Neurosurg. 1997;99:130–4. doi: 10.1016/S0303-8467(97)80010-8.
6)

Fujisawa H, Yonaha H, Okumoto K, Uehara H, le T, Nagata Y, et al. Mutism after evacuation of acute subdural hematoma of the posterior fossa. Childs Nerv Syst. 2005;21:234–6. doi: 10.1007/s00381-004-0999-y.
7)

Koh S, Turkel SB, Baram TZ. Cerebellar mutism in children: Report of six cases and potential mechanisms. Pediatr Neurol. 1997;16:218–19. doi: 10.1016/S0887-8994(97)00018-0.
8)

Yokota H, Nakazawa S, Kobayashi S, Taniguchi Y, Yukihide T. [Clinical study of two cases of traumatic cerebellar injury] No Shinkei Geka. 1990;18:67–70.
9)

Kariyattil R, Rahim MI, Muthukuttiparambil U. Cerebellar mutism following closed head injury in a child. Sultan Qaboos Univ Med J. 2015 Feb;15(1):e133-5. Epub 2015 Jan 21. PubMed PMID: 25685374; PubMed Central PMCID: PMC4318595.
10)

Fabozzi F, Margoni S, Andreozzi B, Musci MS, Del Baldo G, Boccuto L, Mastronuzzi A, Carai A. Cerebellar mutism syndrome: From pathophysiology to rehabilitation. Front Cell Dev Biol. 2022 Dec 2;10:1082947. doi: 10.3389/fcell.2022.1082947. PMID: 36531947; PMCID: PMC9755514.
11)

Yang W, Li Y, Ying Z, Cai Y, Peng X, Sun H, Chen J, Zhu K, Hu G, Peng Y, Ge M. A presurgical voxel-wise predictive model for cerebellar mutism syndrome in children with posterior fossa tumors. Neuroimage Clin. 2022 Dec 13;37:103291. doi: 10.1016/j.nicl.2022.103291. Epub ahead of print. PMID: 36527996; PMCID: PMC9791171.
12)

Toescu SM, Hales PW, Cooper J, Dyson EW, Mankad K, Clayden JD, Aquilina K, Clark CA. Arterial Spin-Labeling Perfusion Metrics in Pediatric Posterior Fossa Tumor Surgery. AJNR Am J Neuroradiol. 2022 Oct;43(10):1508-1515. doi: 10.3174/ajnr.A7637. Epub 2022 Sep 22. PMID: 36137658; PMCID: PMC9575521.
13)

Ballestero M, de Oliveira RS. The importance of olivary hypertrophic degeneration as a differential diagnosis in cerebellar mutism syndrome. Childs Nerv Syst. 2022 Dec 21. doi: 10.1007/s00381-022-05815-x. Epub ahead of print. PMID: 36542117.
14) , 16)

Kirk EA, Howard VC, Scott CA. Description of posterior fossa syndrome in children after posterior fossa brain tumor surgery. J Pediatr Oncol Nurs. 1995 Oct;12(4):181-7. PubMed PMID: 7495523.
15)

Doxey D, Bruce D, Sklar F, Swift D, Shapiro K. Posterior fossa syndrome: identifiable risk factors and irreversible complications. Pediatr Neurosurg. 1999 Sep;31(3):131-6. PubMed PMID: 10708354.

Tranexamic acid for intracranial meningioma

Tranexamic acid for intracranial meningioma

Based upon Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), Wijaya et al. from the Universitas Pelita Harapan, Tangerang, BantenIndonesia, Cedars-Sinai Medical Center, Los Angeles, CES University, El Poblado, Medellín, Antioquia, Colombia. collected fully published English literature on the administration of tranexamic acid for patients undergoing intracranial meningioma surgery using the keywords [“tranexamic acid” and “meningioma”] and its synonyms from Cochrane Central Register of Controlled Trials Database, the WHO International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov, and PubMed. The primary outcome of the current study was total blood loss. The secondary outcomes include individuals requiring blood transfusionanesthesia duration, surgical duration, and complication rate. Each included study’s quality was assessed using the JADAD scale.

For qualitative and quantitative data synthesis, they included five RCTs (n = 321) with a mean age was 47.5 ± 11.9 years for the intervention group and 47.2 ± 11.9 years for the control group. The meta-analysis showed that the administration of TXA is associated with decreased total blood loss of standardized mean difference (SMD) of -1.40 (95% CI [-2.49, -0.31]), anesthetic time SMD -0.36 (95% CI [-0.63, -0.09]), and blood transfusion requirements RR 0.58 (95% CI [0.34, 0.99]).

The current study showed that TXA was associated with reduced intraoperative blood loss and intraoperative and postoperative blood transfusion. However, the studies are small. More RCT studies with a greater sample size are favorable 1).

Patients with supratentorial meningiomas and deemed suitable for surgical resection will be recruited in the trial. Patients will be randomized to receive either a single administration of 20 mg/kg TXA or a placebo of the same volume with a 1:1 allocation ratio after anesthesia induction. The primary endpoint is the cumulative incidence of early postoperative seizures within 7 days after craniotomy. Secondary outcomes include the incidence of non-seizure complications, changes in hemoglobin level from baseline, intraoperative blood loss, erythrocyte transfusion volume, Karnofsky Performance Status, all-cause mortality, length of stay, and total hospitalization cost.

Ethics and dissemination: This trial is registered at ClinicalTrial.gov and approved by the Chinese Ethics Committee of Registering Clinical Trials (ChiECRCT20200224). The findings will be disseminated in peer-reviewed journals and presented at national or international conferences relevant to the subject fields.

Trial registration number: NCT04595786 2).


conducted a prospective, randomized double-blind clinical study. The patient scheduled to undergo excision of intracranial meningioma were randomly assigned to receive intraoperatively either intravenous TXA or placebo. Patients in the TXA group received an intravenous bolus of 20 mg/kg over 20 min followed by an infusion of 1 mg/kg/h up to surgical wound closure. Efficacy was evaluated based on total blood loss and transfusion requirements. Postoperatively, thrombotic complications, convulsive seizure, and hematoma formation were noted.

Ninety-one patients were enrolled and randomized: 45 received TXA (TXA group) and 46 received placebo (group placebo). Total blood loss was significantly decreased in the TXA group compared to the placebo (283 ml vs. 576 ml; P < 0.001). Transfusion requirements were comparable in the two groups (P = 0.95). The incidence of thrombotic complications, convulsive seizure, and hematoma formation were similar in the two groups.

TXA significantly reduces intraoperative blood loss but did not significantly reduce transfusion requirements in adults undergoing resection of intracranial meningioma 3).

Thirty patients aged 18-65 years undergoing elective meningioma resection surgery were given either tranexamic acid or placebo (0.9% saline), tranexamic acid at a loading dose of 20 mg/kg, and infusion of 1 mg/kg/h during surgery. The intraoperative blood loss, coagulation profile, and the surgical field using the Likert scale were assessed.

The patients in the tranexamic group had significantly decreased intraoperative blood loss compared to the placebo group (616.42 ± 393.42 ml vs. 1150.02 ± 416.1 ml) (P = 0.02). The quality of the surgical field was better in the tranexamic group (median score 4 vs. 2 on Likert Scale) (P < 0.001). Patients in the tranexamic group had an improved coagulation profile and decreased blood transfusion requirement (p=0.016). The blood collected in the closed suction drain in 24 h postsurgery was less in the tranexamic acid group compared to the placebo group (84.7 ± 50.4 ml vs. 127.6 ± 62.2 ml) (P = 0.047).

Tranexamic acid bolus followed by infusion reduces perioperative blood loss by 46.43% and blood transfusion requirement with improved surgical field and coagulation profile in patients undergoing intracranial meningioma resection surgery 4).


In the Department of Neurosurgery, All India Institute of Medical Sciences (AIIMS), New Delhi, India, Sixty adults undergoing elective craniotomy for meningioma excision were randomized to receive either tranexamic acid or placebo, initiated prior to skin incision. Patients in the tranexamic acid group received an intravenous bolus of 20mg/kg over 20min followed by an infusion of 1mg/kg/h till the conclusion of surgery. Intraoperative blood loss, transfusion requirements, and estimating surgical hemostasis using a 5-grade scale were noted. Postoperatively, the extent of tumor excision on CT scan and complications were observed. Demographics, tumor characteristics, amount of fluid infusion, and duration of surgery and anesthesia were comparable between the two groups. The amount of blood loss was significantly less in the tranexamic acid group compared to the placebo (830mlvs 1124ml; p=0.03). The transfusion requirement was less in the tranexamic acid group (p>0.05). The patients in the tranexamic acid group fared better on a 5-grade surgical hemostasis scale with more patients showing good hemostasis (p=0.007). There were no significant differences between the groups regarding the extent of tumor removal, perioperative complications, hospital stay, or neurologic outcome. To conclude, the administration of tranexamic acid significantly reduced blood loss in patients undergoing excision of meningioma. Fewer patients in the tranexamic acid group received blood transfusions. Surgical field hemostasis was better achieved in patients who received tranexamic acid 5).

A man in his 40s with a history of coronary artery disease previously treated with a drug-eluting stent presented for elective craniotomy and resection of an asymptomatic but enlarging meningioma. During his craniotomy, he received desmopressin and tranexamic acid for surgical bleeding. Postoperatively, the patient developed chest pain and was found to have an ST-elevation myocardial infarction (MI). Because of the patient’s recent neurosurgery, standard post-MI care was contraindicated and he was managed symptomatically in the intensive care unit. The echocardiogram on a postoperative day 1 demonstrated no regional wall motion abnormalities and an ejection fraction of 60%. His presentation was consistent with the thrombosis of his diagonal stent. He was transferred out of the intensive care unit on postoperative day 1 and discharged home on postoperative day 3 6).


Raghavendra et al. report the intraoperative use of tranexamic acid to secure complete hemostasis as a rescue measure in intracranial meningioma resection in uncontrollable bleeding 7).


Three of 13 patients with intracranial meningiomas showed the pre-and postoperative elevation of tissue-type plasminogen activator (t-PA) related fibrinolytic activity in euglobulin fractions (EFA). During the operation, two of these three patients showed a significant elevation of the level of fibrinogen degradation products and oozing in the operating field. However, oozing was not observed in the third patient who had been given tranexamic acid preoperatively. Fibrin autography revealed that a broad lytic band of mol wt 50-60 kDa, probably free t-PA, appeared in the plasma obtained from two of the three patients after the operation when EFA elevated significantly. In all patients studied, the t-PA antigen levels were normal preoperatively but increased both during and after the operation, and correlated mainly with the intensities of a lytic band of mol wt 110 kDa, probably t-PA complexed with its major inhibitor (PAI-1). These results suggest that excessive fibrinolysis can induce local hemorrhagic diathesis during operation and may be related to t-PA function in plasma 8).


1)

Wijaya JH, July J, Quintero-Consuegra M, Chadid DP. A systematic review and meta-analysis of the effects of tranexamic acid in surgical procedure for intracranial meningioma. J Neurooncol. 2023 Jan 12. doi: 10.1007/s11060-023-04237-2. Epub ahead of print. PMID: 36633801.
2)

Li S, Yan X, Li R, Zhang X, Ma T, Zeng M, Dong J, Wang J, Liu X, Peng Y. Safety of intravenous tranexamic acid in patients undergoing supratentorial meningiomas resection: protocol for a randomized, parallel-group, placebo control, non-inferiority trial. BMJ Open. 2022 Feb 2;12(2):e052095. doi: 10.1136/bmjopen-2021-052095. PMID: 35110315; PMCID: PMC8811564.
3)

Rebai L, Mahfoudhi N, Fitouhi N, Daghmouri MA, Bahri K. Intraoperative tranexamic acid use in patients undergoing excision of intracranial meningioma: Randomized, placebo-controlled trial. Surg Neurol Int. 2021 Jun 14;12:289. doi: 10.25259/SNI_177_2021. PMID: 34221620; PMCID: PMC8247750.
4)

Ravi GK, Panda N, Ahluwalia J, Chauhan R, Singla N, Mahajan S. Effect of tranexamic acid on blood loss, coagulation profile, and quality of the surgical field in intracranial meningioma resection: A prospective randomized, double-blind, placebo-controlled study. Surg Neurol Int. 2021 Jun 7;12:272. doi: 10.25259/SNI_296_2021. PMID: 34221603; PMCID: PMC8247710.
5)

Hooda B, Chouhan RS, Rath GP, Bithal PK, Suri A, Lamsal R. Effect of tranexamic acid on intraoperative blood loss and transfusion requirements in patients undergoing excision of intracranial meningioma. J Clin Neurosci. 2017 Mar 7. pii: S0967-5868(16)31491-6. doi: 10.1016/j.jocn.2017.02.053. [Epub ahead of print] PubMed PMID: 28283245.
6)

Westfall KM, Ramcharan RN, Anderson HL 3rd. Myocardial infarction after craniotomy for asymptomatic meningioma. BMJ Case Rep. 2022 Dec 29;15(12):e252256. doi: 10.1136/bcr-2022-252256. PMID: 36581354; PMCID: PMC9806024.
7)

Raghavendra H, Varsha KS, Reddy MA, Kumar SS, Sunanda G, Nagarjuna T, Latha S. Rescue Measure in Giant Intracranial Meningioma Resection by Tranexamic Acid. J Neurosci Rural Pract. 2017 Aug;8(Suppl 1):S127-S129. doi: 10.4103/jnrp.jnrp_198_17. PMID: 28936089; PMCID: PMC5602238.
8)

Tsuda H, Oka K, Noutsuka Y, Sueishi K. Tissue-type plasminogen activator in patients with intracranial meningiomas. Thromb Haemost. 1988 Dec 22;60(3):508-13. PMID: 3149049.

Preoperative Embolization for Brain Arteriovenous Malformation

Preoperative Embolization for Brain Arteriovenous Malformation

Preoperative embolization has traditionally been regarded as a safe and effective adjunct to cerebral arteriovenous malformation surgery. However, there is currently no high-level evidence to ascertain this presumption.

Sattari et al. from the Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. Tehran School of Medicine, Tehran University of Medical Science, Tehran, Iran. compared the outcomes of microsurgery (MS) vs microsurgery with preoperative embolization (E + MS) in patients with cerebral arteriovenous malformation through a systematic review.

They searched MEDLINEPubMed, and Embase. The primary outcome was cerebral arteriovenous malformation obliterationSecondary outcomes were intraoperative bleeding (mL), complications, worsened modified Rankin Scale (mRS), and mortality. The pooled proportions of outcomes were calculated through the logit transformation method. The odds ratio (OR) of categorical data and the mean difference of continuous data were estimated through the Mantel-Haenszel and the inverse variance methods, respectively.

Thirty-two studies met the eligibility criteria. One thousand eight hundred twenty-eight patients were treated by microsurgery alone, and 1088 were treated by microsurgery with preoperative embolization, respectively. The meta-analysis revealed no significant difference in AVM obliteration (94.1% vs 95.6%, OR = 1.15 [0.63-2.11], P = .65), mortality (1.7% vs 2%, OR = 0.88 [0.30-2.58], P = .82), procedural complications (18.2% vs 27.2%, OR = 0.47 [0.19-1.17], P = .10), worsened mRS (21.2% vs 18.5%, OR = 1.08 [0.33-3.54], P = .9), and intraoperative blood loss (mean difference = 182.89 [-87.76, 453.55], P = .19).

The meta-analysis showed no significant difference in AVM obliteration, mortality, complications, worse mRS, and intraoperative blood loss between MS and E + MS groups. For AVMs where MS alone has acceptable results, it is reasonable to bypass unnecessary preoperative embolization given the higher postoperative complication risk 1).


In a meta-analysis, preoperative embolization appears to have substantially reduced the lesional volume with active AV shunting before AVM resection. Anecdotally, preoperative embolization facilitates safe and efficient resection; however, differences in outcomes were not significant. The decision to pursue preoperative embolization remains a nuanced decision based on individual lesion anatomy and treatment team experience 2).


Brosnan et al. performed a systematic review of randomized trials and cohort studies evaluating preoperative embolization of bAVMs published between 01 January 2000 and 31 March 2021 and appraise its role in clinical practice. A MEDLINE search was performed, and articles reporting on outcomes following preoperative embolization, as an adjunct to microsurgery, were eligible for inclusion. PRISMA reporting and Cochrane Handbook guidelines were followed. The primary outcome measure was the risk of complications associated with preoperative embolization. The study was registered with PROSPERO (CRD42021244231). Of the 1661 citations, 8 studies with 588 patients met predefined inclusion criteria. No studies specifically compared outcomes of surgical excision of bAVMs between those with and without preoperative embolization. Spetzler Martin (SM) grading was available in 301 cases. 123 of 298 (41⋅28%) patients presented with hemorrhage. Complications related to embolization occurred in 175/588 patients (29.4%, 95% CI 19.6-40.2). Permanent neurological deficits occurred in 36/541 (6%, 95% CI 3.9-8.5) and mortality in 6/588 (0.41%, 95% CI 0-1.4). This is the first systematic review evaluating the preoperative embolization of bAVMs. Existing studies assessing this intervention are of poor quality. Associated complication rates are significant. Based on published literature, there is currently insufficient evidence to recommend the preoperative embolization of AVMs. Further studies are required to ascertain if there are benefits of this procedure and if so, in which cases 3).

A study included patients with brain AVM who underwent embolization at our hospital between April 2011 and May 2021. Risk factors for peri- and postoperative complications were analyzed.

During the study period, 36 AVMs were treated during 58 embolization sessions. The goal of the embolization was preoperative in 24 (67%), pre-radiosurgical in 9 (25%), and palliative in 3 (8%) cases. The overall complication rate was 43% (25 of 58) per session and 36% (13 of 36) per patient. Ischemic and hemorrhagic complications were observed in 14 (24%) and 14 (24%) cases, respectively. n-Butyl cyanoacrylate (n-BCA) embolization was detected as the significant risk for postoperative hemorrhage in the univariate (79% vs. 36%, P = 0.012; Fisher exact test) and the multivariable analysis (odds ratio 4.90, 95% confidence interval 1.08-22.2, P = 0.039). The number of embolized feeder in a single session also tended to be higher in a hemorrhagic complication group (median 3.5 vs. 2.0, P = 0.11; Mann-Whitney U-test).

The risk of embolization in multimodality treatment for complex brain AVM was substantial. n-BCA embolization may carry a higher risk of postoperative hemorrhage. An accumulation of cases is awaited to investigate the effectiveness of minimal target embolization in the future 4).


A total of 11 patients who underwent 12 preoperative SPE procedures were included for analysis. Five AVMs were ruptured (45%), and the median nidus volume was 3.0 cm3 (range: 1.3-42.9 cm3). The Spetzler-Martin grade was I-II in seven patients (64%) and III-IV in four patients (36%). The degree of nidal obliteration was less than 25% in two procedures (17%), 25-50% in one procedure (8%), 50-75% in eight procedures (67%), and greater than 75% in one procedure (8%). The rates of post-embolization AVM hemorrhage and mortality were 8% and 0%, respectively. The postoperative angiographic obliteration rate was 100%, and the modified Rankin Scale score improved or stable in 91% of patients (median follow-up duration 2 months).

Preoperative AVM SPE affords a reasonable risk-to-benefit profile for appropriately selected patients 5)


Embolization of intracranial arteriovenous malformations (AVMs) is generally a preoperative adjunctive procedure in the USA.

Preoperative embolization may also be a contributing factor with the potential for recurrence of unresected but embolized portions of an AVM. Follow-up angiography at 1 to 3 years appears to be warranted 6).


A total of 107 patients were treated for cAVMs during the study period. Of those patients, 41 underwent cAVM embolizations with Onyx in 82 procedures.

Results: After the embolization, the cAVM diameter was reduced from 3.71 +/- 1.55 cm to 3.06 +/- 1.89 cm (P < .05). Median volume reduction was 75%. Complete occlusion with embolization alone was achieved in 4 (10%) cAVMs. The recurrence rate for completely occluded cAVMs was 50% (2 patients). A total of 71% of the 41 patients treated with Onyx underwent surgery, and 15% underwent radiosurgery. There were 9% who have not yet received definitive treatment of their residual cAVMs. A new permanent neurologic deficit occurred in 5 patients (6.1% per procedure or 12.2% per patient).

A considerable risk for a permanent neurologic deficit remains for cAVM embolization with Onyx. The risk has to be carefully weighted against the benefit of volume reduction in the treatment of cAVMs 7).


1)

Sattari SA, Shahbandi A, Yang W, Feghali J, Xu R, Huang J. Microsurgery versus Microsurgery With Preoperative Embolization for Brain Arteriovenous Malformation Treatment: A Systematic Review and Meta-analysis. Neurosurgery. 2023 Jan 1;92(1):27-41. doi: 10.1227/neu.0000000000002171. Epub 2022 Oct 26. PMID: 36519858.
2)

Park MT, Essibayi MA, Srinivasan VM, Catapano JS, Graffeo CS, Lawton MT. Surgical management outcomes of intracranial arteriovenous malformations after preoperative embolization: a systematic review and meta-analysis. Neurosurg Rev. 2022 Dec;45(6):3499-3510. doi: 10.1007/s10143-022-01860-x. Epub 2022 Sep 27. PMID: 36168072.
3)

Brosnan C, Amoo M, Javadpour M. Preoperative embolisation of brain arteriovenous malformations: a systematic review and meta-analysis. Neurosurg Rev. 2022 Jun;45(3):2051-2063. doi: 10.1007/s10143-022-01766-8. Epub 2022 Mar 9. PMID: 35260972; PMCID: PMC9160113.
4)

Koizumi S, Shojima M, Shinya Y, Ishikawa O, Hasegawa H, Miyawaki S, Nakatomi H, Saito N. Risk Factors of Brain Arteriovenous Malformation Embolization as Adjunctive Therapy: Single-Center 10-Year Experience. World Neurosurg. 2022 Sep 18:S1878-8750(22)01346-8. doi: 10.1016/j.wneu.2022.09.069. Epub ahead of print. PMID: 36130658.
5)

Conger JR, Ding D, Raper DM, Starke RM, Durst CR, Liu KC, Jensen ME, Evans AJ. Preoperative Embolization of Cerebral Arteriovenous Malformations with Silk Suture and Particles: Technical Considerations and Outcomes. J Cerebrovasc Endovasc Neurosurg. 2016 Jun;18(2):90-99. doi: 10.7461/jcen.2016.18.2.90. Epub 2016 Jun 30. PMID: 27790398; PMCID: PMC5081503.
6)

Ivanov AA, Alaraj A, Charbel FT, Aletich V, Amin-Hanjani S. Recurrence of Cerebral Arteriovenous Malformations Following Resection in Adults: Does Preoperative Embolization Increases the Risk? Neurosurgery. 2016 Apr;78(4):562-71. doi: 10.1227/NEU.0000000000001191. PubMed PMID: 26702837.
7)

Hauck EF, Welch BG, White JA, Purdy PD, Pride LG, Samson D. Preoperative embolization of cerebral arteriovenous malformations with onyx. AJNR Am J Neuroradiol. 2009 Mar;30(3):492-5. doi: 10.3174/ajnr.A1376. Epub 2008 Dec 26. PMID: 19112062; PMCID: PMC7051448.

Frontal sinus cranialization

Frontal sinus cranialization


Cranialization refers to the removal of the posterior table of the frontal sinus with occlusion of the inlet into the frontonasal ducts and allowing the neural structures, mainly frontal lobes of the brain and the intact dura, to move directly posterior to the anterior table of the frontal bone 1).

Frontal sinus cranialization with closure via bifrontal pericranial flaps is the gold standard for separating the nasofrontal recess from the intracranial cavity for posterior table defects. Despite the high success rate, cerebrospinal fluid (CSF) leak may persist and is particularly challenging when vascularized reconstructive options from the bicoronal incision are exhausted.

For appropriately selected patients with extensive frontal injuries, cranialization is a procedure that provides an excellent margin of long-term safety and a satisfactory esthetic outcome. Individual surgeons will continue to differ at times as to the appropriate management of a particular frontal injury. Nevertheless, for the most severe of these, cranialization continues to be the definitive treatment 2).


In the case series of Donath and Sindwani indications included extensive frontal sinus fractures involving the posterior table (78.9%), mucocele (10.5%), arteriovenous malformation (5.3%), and frontal bone osteomyelitis (5.3%). 3).


For Calis et al. it seems that isolated anterior table fractures with a maximum amount of displacement of less than 4.5 mm can be treated conservatively without leading to contour deformities. CSF leakage in the acute setting might not always require cranialization and this may spontaneously resolve within 10 days. Cranialization should be considered whenever CSF leakage lasts longer than 10 days 4).


For Echo et al. the first step in assessing frontal sinus fractures involves the assessment of the posterior table of the frontal sinus and determining the need for cranialization. Criteria for cranialization include severe posterior table fracture, CSF leak greater than 1 to 2 weeks, or in any situation where a craniotomy is otherwise indicated. Any patient who meets these criteria would undergo a cranialization of the frontal sinus, obliteration of the nasofrontal outflow tracts, and reconstruction of the anterior table 5).


Using a pedicle vascularized pericranial flap as an extra layer and an autologous fence above the dura adds more protection to the brain. This flap may reduce the risk of CSF leak and perioperative infections and improve the overall results. Yet, more prospective and randomized trials are recommended 6).


Cranialization of the frontal sinus appears to be a good option for the prevention of secondary mucocele development after open excision of benign frontal sinus lesions 7).

A retrospective review of 3 patients (all male; ages 42, 43, and 69 yr) with persistent CSF leak despite frontal sinus cranialization and repair with bifrontal pericranium was performed. Etiology of injury was traumatic in 2 patients and iatrogenic in 1 patient after anaplastic meningioma treatment. To create space for the flap and repair the nasofrontal ducts, endoscopic Draf III (Case 1, 3) or Draf IIb left frontal sinusotomy (Case 2) was performed. The forearm flap was harvested, passed through a Caldwell-Luc exposure, and placed within the Draf frontal sinustomy. The flap vessels were tunneled to the left neck and anastomosed to the facial vessels by the mandibular notch.

Intraoperatively, the flaps were well-seated and provided a watertight seal. Postoperative hospital courses were uncomplicated. There were no new CSF leaks or flap necrosis at 12, 14, and 16 mo.

Endoscopic endonasal free flap reconstruction through a Draf procedure is a novel viable option for persistent CSF leak after failed frontal sinus cranialization 8).


Soto et al. presented the outcome data from 28 cases of frontal sinus trauma due to gunshot wounds. There was a statistically significant difference (P = 0.049) in the type reconstructive strategy employed with each type of flap, with pericranial flaps primarily used in cranialization, temporal grafts were more likely to be used in obliteration, and free flaps were more likely to be used in cranialization. The overall major complication rate was 52% (P = 0.248), with the most common acute major complication being cerebrospinal fluid leak (39%) and the major chronic was an abscess (23.5%).

This report explores the management of frontal sinus trauma and presents short-term outcomes of treatment for penetrating gunshot wounds at a tertiary referral center 9).


Shin et al. suggested a combination flap of galea and reverse temporalis muscle as a method for reconstruction of huge skull base defect.

From 2016 to 2019, a retrospective review was conducted, assessing 7 patients with bone defect which is not just opening of frontal sinus but extends to frontal sinus and cribriform plate. Reconstructions were done by combination of galeal flap and reverse temporalis muscle flap transposition.

Defects were caused by nasal cavity tumor with intracranial extension or brain tumor with nasal cavity extension. There was no major complication in every case. During the follow up period, no patient had signs of complication such as ascending infection, herniation and CSF rhinorrhea. Postoperative radiologic images of all patients that were taken at least 6 months after the surgery showed that flaps maintained the lining and the volume well.

Conventional reconstruction of skull base defect with galeal flap is not effective enough to cover the large sized defect. In conclusion, galeal flap in combination with reverse temporalis muscle flap can effectively block the communication of nasal cavity and intracranium 10).


19 patients underwent (bilateral) frontal sinus cranialization with the pericranial flap between 2000 and 2005. Indications included extensive frontal sinus fractures involving the posterior table (78.9%), mucocele (10.5%), arteriovenous malformation (5.3%), and frontal bone osteomyelitis (5.3%). There were no intraoperative complications. A postoperative cerebrospinal fluid leak occurred in one patient with extensive skull base injuries. This was repaired endoscopically. Follow-up ranged from 9 to 55 months.

The pericranial flap is easily harvested and versatile. Using this vascularized tissue during cranialization affords added protection by providing an extra barrier between the intracranial cavity and the frontal bone and sinonasal tract. This technique is inexpensive, safe, and effective and should be considered when cranialization of the frontal sinus is performed 11).

A 47-year-old man with adenoid cystic carcinoma who underwent secondary reconstruction of the frontal bone with a split-iliac crest bone flap based on the deep circumflex iliac artery. The patient’s course following an initial ablative procedure was complicated by recurrent periorbital cellulitis, radiation, and eventual recurrence of the malignancy. Reconstructive requirements included restoration of the superior orbital rim, cranialization of the frontal sinus, and reconstruction of a sizeable frontal bone defect. In this setting, the iliac crest served as an excellent reconstructive option owing to its natural curvature and large surface area. The split-iliac crest deep circumflex iliac artery bone flap offers a robust and valuable reconstructive option for calvarial defects in hostile surgical fields 12).


2)

Ruggiero, F. P., & Zender, C. A. (2010). Frontal sinus cranialization. Operative Techniques in Otolaryngology-Head and Neck Surgery, 21(2), 143-146. https://doi.org/10.1016/j.otot.2010.03.001
3) , 11)

Donath A, Sindwani R. Frontal sinus cranialization using the pericranial flap: an added layer of protection. Laryngoscope. 2006 Sep;116(9):1585-8. doi: 10.1097/01.mlg.0000232514.31101.39. PMID: 16954984.
4)

Calis M, Kaplan GO, Küçük KY, Altunbulak AY, Akgöz Karaosmanoğlu A, Işıkay Aİ, Mavili ME, Tunçbilek G. Algorithms for the management of frontal sinus fractures: A retrospective study. J Craniomaxillofac Surg. 2022 Oct 4:S1010-5182(22)00144-5. doi: 10.1016/j.jcms.2022.09.007. Epub ahead of print. PMID: 36220677.
5)

Echo A, Troy JS, Hollier LH Jr. Frontal sinus fractures. Semin Plast Surg. 2010 Nov;24(4):375-82. doi: 10.1055/s-0030-1269766. PubMed PMID: 22550461; PubMed Central PMCID: PMC3324222.
6)

Hammad W, Mahmoud B, Alsharif S. Frontal sinus cranialization using pericranial flap: Experience in thirty cases. Saudi J Otorhinolaryngol Head Neck Surg 2021;23:55-9
7)

Horowitz G, Amit M, Ben-Ari O, Gil Z, Abergel A, Margalit N, et al. (2013) Cranialization of the Frontal Sinus for Secondary Mucocele Prevention following Open Surgery for Benign Frontal Lesions. PLoS ONE 8(12): e83820. https://doi.org/10.1371/journal.pone.0083820
8)

Lee JJ, Wick EH, Chicoine MR, Dowling JL, Leuthardt EC, Santiago P, Pipkorn P. Endonasal Free Flap Reconstruction Combined With Draf Frontal Sinusotomy for Complex Cerebrospinal Fluid Leak: A Technical Report & Case Series. Oper Neurosurg (Hagerstown). 2021 Nov 15;21(6):478-484. doi: 10.1093/ons/opab309. PMID: 34423844; PMCID: PMC8599085.
9)

Soto E, Ovaitt AK, Clark AR, Tindal RR, Chiasson KF, Aryanpour Z, Ananthasekar S, Grant JH, Myers RP. Reconstructive Management of Gunshot Wounds to the Frontal Sinus: An Urban Trauma Center’s Perspective. Ann Plast Surg. 2021 Jun 1;86(6S Suppl 5):S550-S554. doi: 10.1097/SAP.0000000000002857. PMID: 33883442; PMCID: PMC8187270.
10)

Shin D, Yang CE, Kim YO, Hong JW, Lee WJ, Lew DH, Chang JH, Kim CH. Huge Anterior Skull Base Defect Reconstruction on Communicating Between Cranium and Nasal Cavity: Combination Flap of Galeal Flap and Reverse Temporalis Flap. J Craniofac Surg. 2020 Feb 7. doi: 10.1097/SCS.0000000000006221. [Epub ahead of print] PubMed PMID: 32049922.
12)

Baudoin ME, Palines PA, Stalder MW. Frontal Cranioplasty with Vascularized Split-iliac Crest Bone Flap. Plast Reconstr Surg Glob Open. 2021 Nov 16;9(11):e3934. doi: 10.1097/GOX.0000000000003934. PMID: 34796087; PMCID: PMC8594656.

Microvascular decompression for hemifacial spasm

Microvascular decompression for hemifacial spasm

see also Hemifacial spasm treatment.


Many ablative procedures are effective for hemifacial spasm (HFS) (including sectioning of divisions of the facial nerve), however, this leaves the patient with some degree of facial paresis. The current procedure of choice for HFS is microvascular decompression (MVD) wherein the offending vessel is physically moved off of the nerve, and a sponge (e.g. Ivalon®, polyvinyl formyl alcohol foam) is interposed as a cushion. Other cushions may not prove to be as satisfactory (muscle may disappear, and Teflon felt may thin 1)).

Most often, the offending vessel approaches the nerve at a right angle, and causes grooving in the nerve. Compression must occur at the root exit zone; decompression of vessels impinging distal to this area is usually ineffective.

Intra-operative brainstem auditory evoked potentials (BAER), 2) or more applicable, direct VIII nerve monitoring 3) may help prevent hearing loss during MVD for 7th or 8th nerve dysfunction. Furthermore, monitoring for the disappearance of the (delayed) synkinetic response may aid in determining when adequate decompression has been achieved (generally reserved for teaching institutions) 4).

The facial nerve should not be manipulated, and one should avoid dissection around the VII and VIII nerves near the IAC 5). Vessels must be preserved, especially the cochlear artery and small perforators. Place gentle medial traction on the cerebellum (<1 cm is recommended 6) ), and incise the arachnoid membrane between the flocculus and the eighth nerve (to avoid tension on nerves that could cause post-op deficit). The IX nerve may be followed medially from the jugular foramen to locate the origin of the VII nerve (the origin of VII is 4 mm cephalad and 2 mm anterior to that of the IX nerve 7)).


Redo MVD remains a feasible treatment option for HFS patients who have failed to benefit from prior MVD, but is associated with higher risks of cranial nerve and vascular injuries 8).

Three-dimensional reconstructions were found to provide much clearer characterization of this area than traditional preoperative imaging. Therefore, Teton et al., suggest that use of these reconstructions in the preoperative setting has the potential to help identify appropriate surgical candidates, guide preoperative planning, and thus improve outcome in patients with HFS 9).

The classic surgical position for microvascular decompression (MVD) is lateral decubitus position with the head rotated 10 degrees away from the affected side.

Ko et al. measured the angles of the posterior fossa, specifically focusing on the surgical corridors used in MVD surgery for hemifacial spasm (HFS), to identify the proper surgical position.

The following parameters were assessed on preoperative magnetic resonance images (MRI): petrous angle (PA), sigmoid angle (SA), sigmoid diameter (SD), and root exit zone-sigmoid sinus edge angle (REZ-SEA).

The mean PA was 59.7 ± 5.6 degrees, SA was 16.8 ± 8.6 degrees, SD was 13.4 ± 3.5 mm, and the mean REZ-SEA was 59.6 ± 5.8 degrees. The difference between the maximum SA to avoid cerebellar hemisphere injury and the minimum REZ-SEA required to verify the facial nerve REZ is assumed to be the usable range of angles for the operative microscope; the average midpoint of this range was 38.2 ± 6.4 degrees.

Turning the patient’s head 10 degrees away from the affected side was generally appropriate for performing MVD surgery because it provided a mean microscope angle of 48 degrees. However, some patients had corner values for the sigmoid angle, REZ-SEA, and sigmoid sinus diameter. Rotating a patient’s head based on precise calculations from preoperative MRI helps to achieve successful surgery 10).

“5–5-5” incision (5mm medial, extending 5cm up to 5cm down), used for approach to seventh/ eighth nerve complex:

A video demonstrates the surgical steps of a MVD at left facial REZ in a 41-year-old man who presented with typical hemifacial spasm on the left side due to VIIth nerve REZ compression by PICA. A classical retromastoid and infrafloccular approach was performed to avoid stretching of the VIIIth nerve and access the VIIth nerve ventro-caudally. The next step is insertion-along the brainstem, VII-VIIIth nerves REZ, and flocculus-of a plaque made of Teflon felt (Edward-type) which is semi-rigid, and by principle does not exert direct compression on the facial REZ, thus avoiding compression and/or transmission of pulsations on the VIIth nerve. The patient’s postoperative period was uneventful and clinical outcome good 11)

Postoperative neurocritical intensive care unit (NICU) admission of patients who underwent craniotomy for close observation is common practice. Hatipoglu Majernik et al. performed a comparative analysis to determine if there is a real need for NICU admission after microvascular decompression (MVD) for cranial nerve disorders or whether it may be abandoned. The study evaluates a consecutive series of 236 MVD surgeries performed for treatment of trigeminal neuralgia (213), hemifacial spasm (17), vagoglossopharyngeal neuralgia (2), paroxysmal vertigo (2), and pulsatile tinnitus (2). All patients were operated by the senior surgeon according to a standard protocol over a period of 12 years. Patients were admitted routinely to NICU during the first phase of the study (phase I), while in the second phase (phase II), only patients with specific indications would go to NICU. While 105 patients (44%) were admitted to NICU postoperatively (phase I), 131 patients (56%) returned to the ward after a short stay in a postanaesthesia care unit (PACU) (phase II). Specific indications for NICU admission in phase I were pneumothorax secondary to central venous catheter insertion (4 patients), AV block during surgery, low blood oxygen levels after extubation, and postoperative dysphagia and dysphonia (1 patient, respectively). There were no significant differences in the distribution of ASA scores or the presence of cardiac and pulmonary comorbidities like congestive heart failure, arterial hypertension, or chronic obstructive pulmonary disease between groups. There were no secondary referrals from PACU to NICU. Our study shows that routine admission of patients after eventless MVD to NICU does not provide additional value. NICU admission can be restricted to patients with specific indications. When MVD surgery is performed in experienced hands according to a standard anaesthesia protocol, clinical observation on a neurosurgical ward is sufficient to monitor the postoperative course. Such a policy results in substantial savings of costs and human resources 12).

Al Menabbawy et al. extracted retrospective data of patients who received Indocyanine green videoangiography from a prospectively maintained database for microvascular decompression. They noted relevant data including demographics, offending vessels, operative technique, outcome, and complications.

Out of the 438 patients, 15 patients with a mean age (SD) of 53 ± 10.5 years underwent intraoperative ICG angiography. Male: female was 1:1.14. The mean disease duration prior to surgery was 7.7 ± 5.3 years. The mean follow-up (SD) was 50.7 ± 42.0 months. In 14 patients, the offending vessel was an artery, and in one patient, a vein. Intraoperative readjustment of the Teflon pledget or sling was required in 20% (3/15) of the cases. No patient had any sort of brainstem ischemia. Eighty percent of the patients (12/15) experienced complete resolution of the spasms. 86.7% (13/15) of the patients reported a satisfactory outcome with marked improvement of the spasms. Three patients experienced slight hearing affection after surgery, which improved in two patients later. There was no facial or lower cranial nerve affection.

Intraoperative ICG is a safe tool for evaluating the flow within the brain stem perforators and avoiding brainstem stroke in MVD for hemifacial spasm 13).


1)

Rhoton AL. Comment on Payner T D and Tew J M: Recurrence of Hemifacial Spasm After Microvascular Decompression. Neurosurgery. 1996; 38
2)

Friedman WA, Kaplan BJ, Gravenstein D, et al. Int raoperative Brain-Stem Auditory Evoked Potentials During Posterior Fossa Microvascular Decompression. J Neurosurg. 1985; 62:552–557
3)

Moller AR, Jannetta PJ. Monitoring Auditory Functions During Cranial Nerve Microvascular Decompression Operations by Direct Recording from the Eighth Nerve. J Neurosurg. 1983; 59:493–499
4)

Moller AR, Jannetta PJ. Microvascular Decompression in Hemifacial Spasm: Intraoperative Electrophysiological Observations. Neurosurgery. 1985; 16:612–618
5) , 6)

Fukushima T, Carter LP, Spetzler RF, Hamilton MG. In: Microvascular Decompression for Hemifacial Spasm: Results in 2890 Cases. Neurovascular Surgery. New York: McGraw-Hill; 1995:1133–1145
7)

Rhoton AL. Microsurgical Anatomy of the Brainstem Surface Facing an Acoustic Neuroma. Surg Neurol. 1986; 25:326–339
8)

Lee S, Park SK, Lee JA, Joo BE, Park K. Missed Culprits in Failed Microvascular Decompression Surgery for Hemifacial Spasm and Expenses for Redo Surgery. World Neurosurg. 2019 May 31. pii: S1878-8750(19)31508-6. doi: 10.1016/j.wneu.2019.05.231. [Epub ahead of print] PubMed PMID: 31158550.
9)

Teton ZE, Blatt D, Holste K, Raslan AM, Burchiel KJ. Utilization of 3D imaging reconstructions and assessment of symptom-free survival after microvascular decompression of the facial nerve in hemifacial spasm. J Neurosurg. 2019 Jul 12:1-8. doi: 10.3171/2019.4.JNS183207. [Epub ahead of print] PubMed PMID: 31299649.
10)

Ko HC, Lee SH, Shin HS. Proper Head Rotation when Performing Microvascular Decompression for Hemifacial Spasm: An Orthometric Consideration Based on Preoperative MRI. J Neurol Surg A Cent Eur Neurosurg. 2022 Feb 15. doi: 10.1055/s-0041-1725950. Epub ahead of print. PMID: 35170003.
11)

Sindou M, Esqueda-Liquidano M, Brinzeu A. Microvascular Decompression for Hemifacial Spasm. Neurosurgery. 2014 Sep 24. [Epub ahead of print] PubMed PMID: 25255262.
12)

Hatipoglu Majernik G, Wolff Fernandes F, Al-Afif S, Heissler HE, Palmaers T, Atallah O, Scheinichen D, Krauss JK. Routine postoperative admission to the neurocritical intensive care unit after microvascular decompression: necessary or can it be abandoned? Neurosurg Rev. 2022 Dec 9;46(1):12. doi: 10.1007/s10143-022-01910-4. PMID: 36482263.
13)

Al Menabbawy A, Refaee EE, Shoubash L, Matthes M, Schroeder HWS. The value of intraoperative indocyanine green angiography in microvascular decompression for hemifacial spasm to avoid brainstem ischemia. Acta Neurochir (Wien). 2022 Oct 27. doi: 10.1007/s00701-022-05389-2. Epub ahead of print. Erratum in: Acta Neurochir (Wien). 2022 Nov 28;: PMID: 36289111.

Rongeur

Rongeur

A rongeur is a strongly constructed instrument with a sharp-edged, scoop-shaped tip, used for gouging out bone. Rongeur is a French word that means rodent or ‘gnawer’.

A rongeur can be used to open a window in bone, often in the skull. It is used in neurosurgery, podiatric surgery, and orthopedic surgery to expose areas for operation.


The Stille-Luer Horsley and Leksell rongeur point straight from the handle, while the duckbill points to the side.


A common example of a surgical rongeur is the Kerrison rongeur, in which its first design was created by Dr. Robert Masters Kerrison (1776–1847), an English physician, but it took more than 100 years before the Kerrison rongeur was modified and took its current form.

Micro straight pituitary rongeur

TachoSil

TachoSil

TachoSil is a collagen sponge coated with the human coagulation factorfibrinogen and thrombin.

The sponge is manufactured from horse tendons. TachoSil reacts upon contact with blood, other body fluids, or saline to form a clot that glues it to the tissue surface. Hemostasis is reached in a few minutes, and the sponge is absorbed by the body within several weeks.

Corza has acquired the assets and licenses that support the development and commercialization of TachoSil®, while Takeda maintains ownership of the manufacturing facility in Linz, Austria.

Some patients experience hypersensitivity or allergy. In rare cases, it could turn into a severe hypersensitive reaction. Those who are prone to having a systemic reaction to horse proteins or human blood products are not good candidates for use of TachoSil.


Among the several autologous fibrin sealants (FS) available, TachoSil(®) (Takeda Austria GmbH, Linz, Austria) stands out for its hemostatic and aerostatic properties, the latter being demonstrated even in high-risk patients after pulmonary resections for primary lung cancers. Several papers available in the literature demonstrated TachoSil(®)’s effectiveness in controlling intraoperative and postoperative bleeding in different surgical branches, including hepatic and pancreatic surgery, as well as cardiac and thoracic surgery. However, the use of TachoSil(®) to control diffuse bleeding following major resections for advanced lung cancers, with the requirement of the chest wall and vertebral body resection for oncological radicality, was never published so far. In this paper, we report three cases of pulmonary lobectomy associated with chest wall resection and hemivertebrectomy for primary malignant lung neoplasms and for a recurrence of malignant solitary fibrous tumor of the pleura in which we used TachoSil(©), which demonstrated its efficacy in controlling diffuse bleeding following resection 1) in the management of diffuse bleeding after chest wall and spinal surgical resection for aggressive thoracic neoplasms. J Thorac Dis. 2016 Jan;8(1):E152-E156. PubMed PMID: 26904247. )).

It is used during surgery to stop local bleeding on internal organs (hemostasis). The sponge is manufactured from horse tendons. TachoSil reacts upon contact with blood, other body fluids, or saline to form a clot that glues it to the tissue surface. Hemostasis is reached in a few minutes, and the sponge is absorbed by the body within several weeks.


Spitaels et al. aimed to compare the efficacy of a fibrin-coated collagen fleece (TachoSil) versus a dural sealant (DuraSeal) to prevent postoperative CSF leakage. We perform a retrospective study comparing two methods of sellar closure during endoscopic endonasal transsphenoidal surgery (EETS) for pituitary adenoma resection: TachoSil patching versus DuraSeal packing. Data concerning diagnosis, reconstruction technique, and surgical outcomes were analyzed. The primary endpoint was the postoperative CSF leak rate. We reviewed 198 consecutive patients who underwent 219 EETS for pituitary adenoma between February 2007 and July 2018. Intraoperative CSF leak occurred in 47 cases (21.5%). A total of 33 postoperative CSF leaks were observed (15.1%). A reduction of postoperative CSF leaks in the TachoSil application group compared to the conventional technique using Duraseal was observed (7.7% and 18.2%, respectively; p = 0.062; Pearson exact test) although non-statistically significant. Two patients required lumbar drainage, and no revision repair was necessary to treat postoperative CSF rhinorrhea in the Tachosil group. Fibrin-coated collagen fleece patching may be a valuable method to prevent postoperative cerebrospinal fluid (CSF) leaks during EETS for pituitary adenoma resection 2).


The use of TachoSil® as a dural sealant in intradural extramedullary tumors surgery 3).

662 patients undergoing craniotomy were included. Three hundred fifty-two were treated with dural sutures alone, and in 310, TachoSil was added after the primary suture. Our primary endpoint was the rate of postoperative complications associated with CSF leakage. Secondary endpoints included functional, disability, and neurological outcomes. A systematic review according to PRISMA guidelines was performed to identify studies comparing primary dural closure with and without additional sealants. Postoperative complications associated with CSF leakage occurred in 24 (7.74%) and 28 (7.95%) procedures with or without TachoSil, respectively (p = 0.960). Multivariate analysis confirmed no significant differences in complication rates between the two groups (aOR 0.97, 95% CI 0.53-1.80, p = 0.930). There were no significant disparities in postoperative functional, disability, or neurological scores. The systematic review identified 661 and included 8 studies in the qualitative synthesis. None showed significant superiority of additional sealants over standard technique regarding complications, rates of revision surgery, or outcome. According to our findings, we summarize that the routinary use of TachoSil and similar products as adjuncts to primary dural sutures after intracranial surgical procedures is safe but without a clear advantage in complication avoidance or outcome. Future studies should investigate whether their use is beneficial in high-risk settings 4).

A case of a patient who underwent cervical arthroplasty complicated by an anterior meningocele 1 month after the first surgery. Imaging revealed a compressive anterior meningocele in relation to the clinically progressive worsening. Revision surgery consisted of a combination of closure of the gap with a fatty patch covered with a TachoSil patch, followed by reinsertion of a new cervical prosthesis. At the last follow-up at 1 year, the patient showed no residual effects of the complication, and the mobility of the disc prosthesis was not impaired by it. Clinical results of the arthroplasty are also very satisfactory. Although these types of complications are rare, it is important to have a consensus on the management of anterior meningocele. TachoSil appears to be a satisfactory option for the management of these complications 5).


1)

Filosso PL, Guerrera F, Sandri A, Zenga F, Lanza GV, Ruffini E, Bora G, Lyberis P, Solidoro P, Oliaro A. Efficacy and safety of human fibrinogen-thrombin patch (Tachosil(®
2)

Spitaels J, Moore J, Zaidman N, Arroteia IF, Appelboom G, Barrit S, Carlot S, De Maertelaer V, Hassid S, De Witte O. Fibrin-coated collagen fleece versus absorbable dural sealant for sellar closure after transsphenoidal pituitary surgery: a comparative study. Sci Rep. 2022 May 14;12(1):7998. doi: 10.1038/s41598-022-12059-x. PMID: 35568737.
3)

Telera S, Caroli F, Raus I, Crispo FM, Pompili A. The use of TachoSil® as dural sealant in intradural extramedullary tumors surgery. J Neurosurg Sci. 2015 Jun;59(2):195-8. PubMed PMID: 25751577.
4)

Carretta A, Epskamp M, Ledermann L, Staartjes VE, Neidert MC, Regli L, Stienen MN. Collagen-bound fibrin sealant (TachoSil®) for dural closure in cranial surgery: single-centre comparative cohort study and systematic review of the literature. Neurosurg Rev. 2022 Dec;45(6):3779-3788. doi: 10.1007/s10143-022-01886-1. Epub 2022 Nov 2. PMID: 36322203; PMCID: PMC9663376.
5)

Lavantes P, Dufour T. Postoperative meningocele after anterior cervical discectomy and arthroplasty on a case report. Pan Afr Med J. 2022 Aug 8;42:257. doi: 10.11604/pamj.2022.42.257.35812. PMID: 36338550; PMCID: PMC9617493.

ShuntScope

ShuntScope

Autoclavable reusable SHUNTSCOPE® is designed to facilitate the endoscopic ventricular drainage placement during shunt surgery.

A retrospective analysis of all pediatric patients undergoing ventricular catheter placement using the ShuntScope from 01/2012 to 01/2022 in the Department of Neurosurgery, Saarland University Medical Center, Homburg was performed. Demographic, clinical, and radiological data were evaluated. The visualization quality of the intraoperative endoscopy was stratified into the categories of excellent, medium, and poor and compared to the postoperative catheter tip placement. Follow-up evaluation included the surgical revision rate due to proximal catheter occlusion.

A total of 65 ShuntScope-assisted surgeries have been performed on 51 children. The mean age was 5.1 years. The most common underlying pathology was a tumor- or cyst-related hydrocephalus in 51%. Achieved image quality was excellent in 41.5%, medium in 43%, and poor in 15.5%. Ideal catheter placement was achieved in 77%. There were no intraoperative ventricular catheter placement complications and no technique-related morbidity associated with the ShuntScope. The revision rate due to proximal occlusion was 4.61% during a mean follow-up period of 39.7 years. No statistical correlation between image grade and accuracy of catheter position was observed (p-value was 0.290).

The ShuntScope can be considered a valuable addition to standard surgical tools in pediatric hydrocephalus treatment. Even suboptimal visualization contributes to high rates of correct catheter placement and, thereby, to a favorable clinical outcome 1).


The purpose of the study is to compare the accuracy of catheter placement and the complication and revision rates between SG and freehand (FH) techniques.

A retrospective study based on a prospectively acquired database of patients who underwent VC placement between September 2018 and July 2021. The accuracy of catheter placement was graded on postoperative imaging using a three-point Hayhurst grading system. Complication and revision rates were documented and compared between both groups with an average follow-up period of 20.84 months.

Results: Fifty-seven patients were included. SG technique was used in 29 patients (mean age was 6.3 years, 1.4 -27.7 years, 48.1% females), and FH technique was used in 28 patients (mean age was 26.7 years, 0.83 – 79.5 years, 67.9% female). The success rate for the optimal placement of the VC with a grade I on the Hayhurst scale was significantly higher in the SG group (93.1%) than in the FH group (60.7%), P = 0.012. The revision rate was higher in the FH group with 35.7% vs. 20.7% of in the SG group, P = 0.211.

Conclusion: VC placement using the SG technique is a safe and effective procedure, which enabled a significantly higher success rate and lower revision and complication rate. Accordingly, we recommend using the SG technique especially in patients with difficult anatomy 2)


The experience of shuntscope-guided ventriculoperitoneal shunt in 9 cases done from June 2015 to April 2016. Shuntscope is a 1 mm outer diameter semi-rigid scope from Karl Storz with 10000 pixels of magnification. It has a fiber optic lens system with a camera and light source attachment away from the scope to make it lightweight and easily maneuverable.

Results: In all cases, VC was placed in the ipsilateral frontal horn away from choroid plexuses, septae, or membranes. Septum pellucidum perforation and placement to the opposite side of the ventricle was identified with shunt scope assistance and corrected.

Conclusion: Although our initial results are encouraging, larger case series would be helpful. Complications and cost due to shunt dysfunction can thus be reduced to a great extent with shuntscope 3)


The semi-rigid ShuntScope (Karl Storz GmbH & Co.KG, Tuttlingen, Germany) with an outer diameter of 1.0 mm and an image resolution of 10,000 pixels was used in a series of 27 children and adolescents (18 males, 9 females, age range 2 months-18 years). Indications included catheter placement in aqueductal stenting (n = 4), first-time shunt placement (n = 5), burr hole reservoir insertion (n = 4), catheter placement after endoscopic procedures (n = 7) and revision surgery of the ventricle catheter (n = 7).

ShuntScope-guided precise catheter placement was achieved in 26 of 27 patients. In one case of aqueductal stenting, the procedure had to be abandoned. One single wound healing problem was noted as a complication. Intraventricular image quality was always sufficient to recognize the anatomical structures. In the case of catheter removal, it was helpful to identify adherent vessels or membranes. Penetration of small adhesions or thin membranes was feasible. Postoperative imaging studies demonstrated catheter tip placements analogous to the intraoperative findings.

Misplacements of shunt catheters are completely avoidable with the presented intra-catheter technique including slit ventricles or even aqueductal stenting. Potential complications can be avoided during revision surgery. The implementation of the ShuntScope is recommended in pediatric neurosurgery 4).


1)

Prajsnar-Borak A, Teping F, Oertel J. Image quality and related outcomes of the ShuntScope for catheter implantation in pediatric hydrocephalus-experience of 65 procedures. Childs Nerv Syst. 2022 Dec 2. doi: 10.1007/s00381-022-05776-1. Epub ahead of print. PMID: 36459211.
2)

Issa M, Nofal M, Miotik N, Seitz A, Unterberg A, El Damaty A. ShuntScope®-Guided Versus Free Hand Technique for Ventricular Catheter Placement: A Retrospective Comparative Study of Intra-Ventricular Catheter Tip Position and Complication Rate. J Neurol Surg A Cent Eur Neurosurg. 2022 Feb 10. doi: 10.1055/a-1768-3892. Epub ahead of print. PMID: 35144299.
3)

Agrawal V, Aher RB. Endoluminal Shuntscope-Guided Ventricular Catheter Placement: Early Experience. Asian J Neurosurg. 2018 Oct-Dec;13(4):1071-1073. doi: 10.4103/ajns.AJNS_98_17. PMID: 30459870; PMCID: PMC6208226.
4)

Senger S, Antes S, Salah M, Tschan C, Linsler S, Oertel J. The view through the ventricle catheter – The new ShuntScope for the therapy of pediatric hydrocephalus. J Clin Neurosci. 2018 Feb;48:196-202. doi: 10.1016/j.jocn.2017.10.046. Epub 2017 Nov 6. PubMed PMID: 29102235.

Chronic subdural hematoma recurrence prevention

Chronic subdural hematoma recurrence prevention

In total, 402 studies were included in this analysis and 32 potential risk factors were evaluated. Among these, 21 were significantly associated with the postoperative recurrence of CSDH. Three risk factors (male, bilateral hematoma, and no drainage) had convincing evidence 1).

The single most important factor appears to be the residual subdural space after drainage of the chronic subdural hematoma and an effort should be made by the surgeon to facilitate the expansion of the underlying brain. The presence of a functioning drain for 48–72 h draining the subdural fluid and promoting brain expansion will reduce the subdural space, thus reducing the recurrence of the CSDH. Some of the relevant surgical nuances include placement of at least two burr holes with the burr holes located to drain multiple cavities, copious irrigation of the subdural space, placement of the drain in the dependent burr hole site, near-total filling of the subdural space with irrigation to prevent a pneumocephalus and placing a subdural drain. Closure of the site with a large piece of Gelfoam prevents the subgaleal blood to migrate into the subdural space.

Postoperative subdural drain of maximal 48 h is effective in reducing recurrent hematomas. However, the shortest possible drainage time without increasing the recurrence rate is unknown

see Subdural drain for chronic subdural hematoma

The effect of a physical property of irrigation solution (at body vs room temperature) on the chronic subdural hematoma recurrence rate needs further study.

Objective: To explore whether irrigation fluid temperature has an influence on cSDH recurrence.

Design, setting, and participants: This was a multicenter randomized clinical trial performed between March 16, 2016, and May 30, 2020. The follow-up period was 6 months. The study was conducted at 3 neurosurgical departments in Sweden. All patients older than 18 years undergoing cSDH evacuation during the study period were screened for eligibility in the study.

Interventions: The study participants were randomly assigned by 1:1 block randomization to the cSDH evacuation procedure with irrigation fluid at room temperature (RT group) or at body temperature (BT group).

Main outcomes and measures: The primary end point was recurrence requiring reoperation within 6 months. Secondary end points were mortality, health-related quality of life, and complication frequency.

Results: At 6 months after surgery, 541 patients (mean [SD] age, 75.8 [9.8] years; 395 men [73%]) had a complete follow-up according to protocol. There were 39 of 277 recurrences (14%) requiring reoperation in the RT group, compared with 16 of 264 recurrences (6%) in the BT group (odds ratio, 2.56; 95% CI, 1.38-4.66; P < .001). There were no significant differences in mortality, health-related quality of life, or complication frequency.

Conclusions and Relevance: In this study, irrigation at body temperature was superior to irrigation at room temperature in terms of fewer recurrences. This is a simple, safe, and readily available technique to optimize outcome in patients with cSDH. When irrigation is used in cSDH surgery, irrigation fluid at body temperature should be considered standard of care.

Trial registration: ClincalTrials.gov Identifier: NCT02757235 2).

A study aimed to evaluate the efficacy and safety of half-saline solution for irrigation in burr hole trephination for chronic subdural hematoma.

This randomized clinical trial was conducted in university hospital referral centers from 2020 to 2021. Sixty-three patients with chronic subdural hematoma eligible for burr hole trephination were primarily enrolled. Two patients were excluded because of concurrent stroke. Sixty-one patients were randomly allocated into case (HS=30) and control (normal-saline [NS]=31) groups. HS was used to irrigate the hematoma in the case group and NS was used in the control group. The patients were followed-up. Clinical variables including demographic and medical findings, postoperative computed tomography findings, postoperative complications, hospitalization period, recurrence rate, and functional status measured by the Barthel type B index were recorded.

Forty-six of 61 patients were male (75.4%), and the patients’ mean age was 65.4±16.9 years, with equal distribution between the 2 groups. Postoperative effusion and postoperative hospital stay duration were significantly lower in the HS group than in the NS group (p=0.002 and 0.033, respectively). The postoperative recurrence within 3 months in both groups was approximately equal (6.6%). In terms of functional outcomes and postoperative complications, HS showed similar results to those of NS.

Conclusion: HS as an irrigation fluid in BHC effectively reduced postoperative effusion and hospital stay duration without considerable complications.

Trial registration: Iranian Registry of Clinical Trials Identifier: IRCT20200608047688N1 3).


1)

Zhu F, Wang H, Li W, Han S, Yuan J, Zhang C, Li Z, Fan G, Liu X, Nie M, Bie L. Factors correlated with the postoperative recurrence of chronic subdural hematoma: An umbrella study of systematic reviews and meta-analyses. EClinicalMedicine. 2021 Dec 20;43:101234. doi: 10.1016/j.eclinm.2021.101234. PMID: 34988412; PMCID: PMC8703229.
2)

Bartley A, Bartek J Jr, Jakola AS, Sundblom J, Fält M, Förander P, Marklund N, Tisell M. Effect of Irrigation Fluid Temperature on Recurrence in the Evacuation of Chronic Subdural Hematoma: A Randomized Clinical Trial. JAMA Neurol. 2022 Nov 21. doi: 10.1001/jamaneurol.2022.4133. Epub ahead of print. PMID: 36409480.
3)

Mahmoodkhani M, Sharafi M, Sourani A, Tehrani DS. Half-Saline Versus Normal-Saline as Irrigation Solutions in Burr Hole Craniostomy to Treat Chronic Subdural Hematomata: A Randomized Clinical Trial. Korean J Neurotrauma. 2022 Sep 29;18(2):221-229. doi: 10.13004/kjnt.2022.18.e47. PMID: 36381457; PMCID: PMC9634318.

Chronic Subdural Hematoma Surgical Technique

Chronic Subdural Hematoma Surgical Technique

(1) Twist drill craniostomy for chronic subdural hematoma is a relatively safe technique that can be employed under local anesthesia and thus can be considered as first-line treatment in high-risk surgical candidates. (2) Single and double burr hole craniotomies have shown comparable results. (3) Intraoperative irrigation during burr-hole craniostomy doesn’t affect the outcome. (4) Drain insertion after hematoma evacuation lowers the recurrence risk. (5) Position of the drain is not significant but early drain removal is associated with higher recurrence rates. (6) Craniotomy is associated with high morbidity and mortality, hence should be reserved for recurrent and large septate hematoma cases. (7) Head elevation in the postoperative period reduces recurrence. (8) Embolization of the middle meningeal artery (EMMA): A novel treatment modality, is promising but requires further approval in terms of large sample-sized multicenter randomized control trials. In conclusion, further research is required on the subject to formulate guidelines regarding the management of this common neurosurgical emergency 1)


Due to the lack of consensus treatment, tissue plasminogen activator (tPA) has begun to be investigated to promote drainage and has shown promise in some early studies in reducing recurrence rates.


The most usual procedures for chronic subdural hematoma treatment include single or multiple burr hole drainage craniectomy. There is still controversy, however, about the risks and benefits of the different surgical approaches and types of drainage.

Till 1970s, craniotomy was the most commonly used method. Burr hole trephination for chronic subdural hematoma became the most preferred method from 1980s. In 1977Twist drill craniostomy for chronic subdural hematoma was introduced. Closed system drainage after a Burr hole (BH) or a Twist drill (TD) became the most frequently used surgical method 2).

Pre-operative evaluation of radiological features of CSDHs is crucial in determining the right indication for minimally invasive drainage. Minimally invasive treatments of CSH may reduce the use of anaesthetic drugs and worsening of pre-existing neurodegenerative disorders 3).

The duration of procedure was significantly more in Burr-Hole Craniostomy BHC than in Twist-Drill Craniostomy TDC. In postoperative outcome, there was no significant difference in the GCS score, motor power improvement, motor power deterioration, overall clinical improvement, and improvement in CT scans of both the groups. Postoperative residue requiring reoperation was significantly more in TDC group. There was no significant difference in the development acute SDH, reoperation rate, complications, death, and hospital stay in both the groups. Avoiding the complications of general anesthesia and giving the equal postoperative improvement and complications of BHC, the TDC is considered as an effective alternative to the BHC in the surgical management of CSDH 4)

Although nonsurgical treatment is often successful, trephination has more advantages, such as rapid resolution of the symptoms and short period of hospitalization. Nonsurgical treatment is possible in asymptomatic patients with a small CSDH. For the symptomatic patients with CSDH, trephination is the treatment of choice, either by BH or TD. In gray zone between surgery and medical treatment, shared decision making can be an ideal approach. For chronic subdural hematoma recurrences, repeated trephination is still effective for patients with a low risk of recurrence. If the risk of recurrence is high, additional management would be helpful. For the refractory CSDHs, it is necessary to obliterate the subdural space 5).


Chronic subdural hematoma treatment in the elderly include observation, operative burr holes or craniotomy, and bedside twist drill drainage. The decision on which technique to use should be determined by weighing the comorbidities and symptoms of the patient with the potential risks and benefits.

Chronic subdural hematoma are ideally treated with surgical drainage. Despite this common practice, there is still controversy surrounding the best surgical procedure. With lack of clear evidence of a superior technique, surgeons are free to base the decision on other factors that are not related to patient care.

Originally, CSDHs were treated by open craniotomy 6) 7) 8) 9). Later burr hole trephination (BHT) was adopted because it was less invasive with lower morbidity and recurrence rates when compared with standard craniotomy 10) 11) 12) 13) 14) 15).

The traditional methods include evacuation via a burr hole with closed system drainage with or without irrigation, two burr-hole craniostomy with closed system drainage with irrigation or craniotomy, with subdural drain or without drain placement.

Minicraniotomy (MC) emerged as an attractive alternative to BHT as it allows better visualisation of the subdural cavity, enabling better haemostasis and resection of membranes.

Although bedside twist drill evacuation may avoid operating room costs and anesthetic complications in an elderly patient population and allow earlier anticoagulation resumption treatment if necessary, there is also a risk of morbidity if uncontrolled bleeding is encountered or the patient is unable to tolerate the bedside procedure. However, bedside twist drill craniostomy is a reasonable and effective option for the treatment of subacute/chronic SDH in patients who may not be optimal surgical candidates 16).


Subperiosteal vs Subdural Drain After Burr-Hole Drainage of Chronic Subdural Hematoma: A Randomized Clinical Trial (cSDH-Drain-Trial) 17).

see Burr hole trephination for chronic subdural hematoma.

see Twist drill craniostomy for chronic subdural hematoma.

see Subdural drain for chronic subdural hematoma.

see Subdural evacuating port system for chronic subdural hematoma.

see Subperiosteal drain for chronic subdural hematoma

see Craniotomy for chronic subdural hematoma.

see Chronic subdural hematoma neuroendoscopy.


1)

Siddique AN, Khan SA, Khan AA, Aurangzeb A. Surgical Treatment Options For Chronic Subdural Haematoma. J Ayub Med Coll Abbottabad. 2022 Jul-Sep;34(3):550-556. doi: 10.55519/JAMC-03-10225. PMID: 36377174.
2) , 5)

Lee KS. How to Treat Chronic Subdural Hematoma? Past and Now. J Korean Neurosurg Soc. 2019 Mar;62(2):144-152. doi: 10.3340/jkns.2018.0156. Epub 2018 Nov 30. PubMed PMID: 30486622; PubMed Central PMCID: PMC6411568.
3)

Certo F, Maione M, Altieri R, Garozzo M, Toccaceli G, Peschillo S, Barbagallo GMV. Pros and cons of a minimally invasive percutaneous subdural drainage system for evacuation of chronic subdural hematoma under local anesthesia. Clin Neurol Neurosurg. 2019 Oct 10;187:105559. doi: 10.1016/j.clineuro.2019.105559. [Epub ahead of print] PubMed PMID: 31639631.
4)

Thavara BD, Kidangan GS, Rajagopalawarrier B. Comparative Study of Single Burr-Hole Craniostomy versus Twist-Drill Craniostomy in Patients with Chronic Subdural Hematoma. Asian J Neurosurg. 2019 Apr-Jun;14(2):513-521. doi: 10.4103/ajns.AJNS_37_19. PubMed PMID: 31143272; PubMed Central PMCID: PMC6516027.
6)

Ernestus R, Beldzinski P, Lanfermann H, Klug N. Chronic subdural hematoma: surgical treatment and outcome in 104 patients. Surg Neurol 1997;48:220–5.
7)

McKissock W, Richardson A, Bloom WH. Subdural hematoma: a review of 389 cases. Lancet 1960;1:1365–9.
8)

Tyson G et al. The role of craniectomy in the treatment of chronic subdural hematomas. J Neurosurg 1980;52:776–81.
9)

Putnam IJ, Cushing H. Chronic subdural hematoma. Its pathology, its relation to pachymeningitis hemorrhagica, and its surgical treatment. Arch Surg 1925;11:329–93.
10)

Chronic Almenawer S et al. Subdural hematoma management: a systematic review and meta-analysis of 34829 patients. Ann Surg 2014;259(3):449–57.
11)

Lee J, Ebel H, Ernestus R, Klug N. Various surgical treatments of chronic subdural hematoma and outcome in 172 patients: is membranectomy necessary? Surg Neurol 2004;61:523–5528.
12)

Ducruet A et al. The surgical management of chronic subdural hematoma. Neurosurg Rev 2012;35:155–69.
13)

Leroy H et al. Predictors of functional outcomes and recurrence of chronic subdural. J Clin Neurosci 2015;22:1895–900.
14)

Regan J, Worley E, Shelburne C, Pullarkat R, Burr Watson J. Hole Washout versus craniotomy for chronic subdural hematoma: patient outcome and cost analysis. PLoS One 2015;10(1):1–8.
15)

Mondorf Y, Abu-Owaimer M, Gaab M, Oertel J. Chronic subdural hematoma – Craniotomy versus burr hole trephination. Br J Neurosurg 2009;23(6):612–6.
16)

Garber S, McCaffrey J, Quigley EP, MacDonald JD. Bedside Treatment of Chronic Subdural Hematoma: Using Radiographic Characteristics to Revisit the Twist Drill. J Neurol Surg A Cent Eur Neurosurg. 2016 Jan 25. [Epub ahead of print] PubMed PMID: 26807616.
17)

Agrawal A, Pacheco-Hernandez A, Moscote-Salazar LR. Letter: Subperiosteal vs Subdural Drain After Burr-Hole Drainage of Chronic Subdural Hematoma: A Randomized Clinical Trial (cSDH-Drain-Trial). Neurosurgery. 2019 Aug 6. pii: nyz289. doi: 10.1093/neuros/nyz289. [Epub ahead of print] PubMed PMID: 31387117.