Lumbar puncture is a useful diagnostic and treatment tool. Although serious events are seldom, they can be detrimental. A precaution not to underestimate such events in practicing lumbar, especially in patients with suboptimum coagulation state. Image-guided procedure can be useful and should be considered in appropriately selected patients 1).
In a Danish cohort study, risk of spinal hematoma following lumbar puncture was 0.20% among patients without coagulopathy and 0.23% among those with coagulopathy. Although these findings may inform decision-making about lumbar puncture by describing rates in this sample, the observed rates may reflect bias due to physicians selecting relatively low-risk patients for lumbar puncture 2).
It is estimated that approximately 4% of symptomatic spinal hematomas are related to traumatic LP. They are commonly located inclusively with the epidural space in 75% of the cases, whereas subarachnoid hemorrhage and spinal subdural hematoma can be found in 15.7% and 4.1%, respectively. Multi-compartmental spinal hematomas are rare and thought to present in 0.33% 3).
In clinical practice, few carry out postprocedural investigation for spinal hematoma unless the patient reports sensory or motor changes after the procedure. In a meta-analysis, approximately 85% of symptomatic spinal hematomas required surgical intervention 4)
Surgery is indicated for symptomatic patients with reported complete neurological recovery in almost 40%. The timing of surgery is vital and associated with improved neurological outcome when done in less than 36 hours 5).
Nevertheless, symptomatic spinal hematoma is a critical condition and we emphasize that surgical intervention should be considered at a low threshold for urgent decompression to optimize overall clinical outcome. Coagulopathy is an important risk factor that should not be underestimated in planning for LP. The presence of pre-existing coagulopathy was found to be a significant poor prognostic factor regardless of surgical intervention. Therefore, an early investigation with spinal MRI should be obtained to rule out an evolving spinal hematoma. Mortality was reported high in patients with compressive cervical spinal epidural hematomas and cardiovascular disease 6).
A case for a patient with Burkitt lymphoma who presented with mild neuroaxial symptoms. An urgent cerebrospinal fluid sample was required which was taken after correcting his platelets count to 53.4 × 109/L. He developed a massive multi-compartmental thoracolumbar hematoma with acute cauda equine syndrome requiring surgical intervention. Despite aggressive management, he remained permanently paraplegic with functional status that negatively affected his overall outcome 7).
Bodilsen J, Mariager T, Vestergaard HH, Christiansen MH, Kunwald M, Lüttichau HR, Kristensen BT, Bjarkam CR, Nielsen H. Association of Lumbar Puncture With Spinal Hematoma in Patients With and Without Coagulopathy. JAMA. 2020 Oct 13;324(14):1419-1428. doi: 10.1001/jama.2020.14895. PMID: 33048155.
Groen RJ, van Alphen HA. Operative treatment of spontaneous spinal epidural hematomas: a study of the factors determining postoperative outcome. Neurosurgery. 1996 Sep;39(3):494-508; discussion 508-9. doi: 10.1097/00006123-199609000-00012. PMID: 8875479.
Mendes et al. presented the case of a 49-year-old woman diagnosed with idiopathic trigeminal neuralgia refractory to pharmacological treatment. After failure of puncture by conventional fluoroscopy for percutaneous gasserian ganglion balloon compression due to a narrow foramen ovale, the patient was submitted to puncture guided by computed tomography.
Alternative imaging methods, such as computed tomography, should be considered when Percutaneous Foramen Ovale Puncture by conventional single-plane fluoroscopy fails, to minimize the risk of potential complications triggered by frustrated puncture attempts 1).
Cannulation procedures, including those utilizing neuronavigational technology, are occasionally complicated by anatomical variation of the FO, sometimes resulting in miscannulation and subsequent adverse events. The FO, while commonly thought of as oval-shaped, has also been described as “almond,” “banana,” “D shape,” “pear,” and “triangular.” 2).
Guo et al., described a technique that includes a stereotactic approach in the preoperative plan in cases where the foramen ovale is difficult to access for radiofrequency thermocoagulation of the Gasserian ganglion.
The study included 395 patients for whom three-dimensional computed tomographic reconstruction of the skull base, maxilla, and mandible was conducted before surgery. Accessibility of the foramen ovale was defined using numerical data from the three-dimensional computed tomographic reconstruction images. In those patients for whom accessibility of the foramen ovale was considered difficult, the authors used a stereotactic frame to design an individual operative plan. Adjustments of a single point of data,-that is, a change in X axis, Y axis, or an arc angle-were guided by radiographic fluoroscopy images. After verifying successful cannulation and electroneurophysiology, thermocoagulation targets-especially multiple targets recorded as data on the Z axis of the stereotactic approach-were identified and treated.
There were 24 patients who met the predetermined criteria for having a difficult-to-access foramen ovales-that is, they had at least two contributing factors and/or involvement of division V1 . Twenty-one of the 24 patients required a single satisfactory puncture; three patients required two to three punctures to successfully access the foramen ovale. There were no permanent complications from the procedure.
The authors conclude that this stereotactic approach combined with three-dimensional computed tomographic reconstruction model can improve the accuracy, safety, and efficiency of percutaneous radiofrequency thermocoagulation in patients with trigeminal neuralgia for whom the foramen ovale is difficult to access 4).
Ding et al., assessed the feasibility of accessing the Gasserian ganglion through the FO from a mandibular angle under computed tomography (CT) and neuronavigation guidance.A total of 108 patients with TN were randomly divided into 2 groups (Group G and Group H) using a random number table. In Group H, anterior Hartel approach was used to puncture the FO; whereas in Group G, a percutaneous puncture through a mandibular angle was used to reach the FO. In both groups, procedures were guided by CT imaging and neuronavigation. The success rates, therapeutic effects, complications, and recurrence rates of the 2 groups were compared.The puncture success rates in Group H and Group G were 52/54 (96.30%) and 49/54 (90.74%), respectively (P = 0.24). The 2 procedural failures in Group H were rescued by using submandibular trajectory, and the 5 failures in Group G were successfully reapproached by Hartel method. Therapeutic effects as measured by Barrow Neurological Institute Pain Scale (P = 0.03) and quality of life (QOL) scores (P = 0.04) were significantly better in Group G than those in Group H at 36 months posttreatment. Hematoma developed in 1/54 (1.85%) cases in Group H, and no cases of hematoma were observed in Group G (P = 0.33). In Group H, RFT resulted in injury to the unintended trigeminal nerve branches and motor fibers in 27/52 (51.92%) cases; in Group G, it resulted in the same type of injury in 7/49 cases (14.29%) (P < 0.01). In Group H, the 24- and 36-month recurrence rates were 12/51 (23.53%) and 20/51 (39.22%), respectively; in Group G, these recurrence rates were 7/49 (12.24%) and 9/49 (16.33%, P = 0.03), respectively.CT- and neuronavigation-guided puncture from a mandibular angle through the FO into the Gasserian ganglion can be safely and effectively used to deliver RFT for the treatment of pTN. This method may represent a viable option to treat TN in addition to Hartel approach 5).
The goals of a study of Peris-Celda et al., were to demonstrate the anatomical basis of complications related to FO puncture, and provide anatomical landmarks for improvement of safety, selective lesioning of the trigeminal nerve (TN), and optimal placement of electrodes.
Both sides of 50 dry skulls were studied to obtain the distances from the FO to relevant cranial base references. A total of 36 sides from 18 formalin-fixed specimens were dissected for Meckel cave and TN measurements. The best radiographic projection for FO visualization was assessed in 40 skulls, and the optimal trajectory angles, insertion depths, and topographies of the lesions were evaluated in 17 specimens. In addition, the differences in postoperative pain relief after the radiofrequency procedure among different branches of the TN were statistically assessed in 49 patients to determine if there was any TN branch less efficiently targeted.
Most severe complications during FO puncture are related to incorrect needle placement intracranially or extracranially. The needle should be inserted 25 mm lateral to the oral commissure, forming an approximately 45° angle with the hard palate in the lateral radiographic view, directed 20° medially in the anteroposterior view. Once the needle reaches the FO, it can be advanced by 20 mm, on average, up to the petrous ridge. If the needle/radiofrequency electrode tip remains more than 18 mm away from the midline, injury to the cavernous carotid artery is minimized. Anatomically there is less potential for complications when the needle/radiofrequency electrode is advanced no more than 2 mm away from the clival line in the lateral view, when the needle pierces the medial part of the FO toward the medial part of the trigeminal impression in the petrous ridge, and no more than 4 mm in the lateral part. The 40°/45° inferior transfacial-20° oblique radiographic projection visualized 96.2% of the FOs in dry skulls, and the remainder were not visualized in any other projection of the radiograph. Patients with V1 involvement experienced postoperative pain more frequently than did patients with V2 or V3 involvement. Anatomical targeting of V1 in specimens was more efficiently achieved by inserting the needle in the medial third of the FO; for V2 targeting, in the middle of the FO; and for V3 targeting, in the lateral third of the FO.
Knowledge of the extracranial and intracranial anatomical relationships of the FO is essential to understanding and avoiding complications during FO puncture. These data suggest that better radiographic visualization of the FO can improve lesioning accuracy depending on the part of the FO to be punctured. The angles and safety distances obtained may help the neurosurgeon minimize complications during FO puncture and TN lesioning 6).
Koizuka et al., presented a new method for percutaneous radio-frequency thermocoagulation of the Gasserian ganglion, in which computed tomography (CT) fluoroscopy is used to guide needle placement.
In the present study, 15 patients with trigeminal neuralgia underwent percutaneous radio-frequency thermocoagulation of the Gasserian ganglion guided by high-speed real-time CT fluoroscopy.
RESULTS: Trigeminal neuralgia was improved in all patients after treatment without any severe complications. Moderate dysesthesia occurred in only one case.
CT fluoroscopy-guided percutaneous radio-frequency thermocoagulation of the Gasserian ganglion was safe, quick, and effective for patients with intractable idiopathic trigeminal neuralgia 7).
Mendes PD, Martins da Cunha PH, Monteiro KKO, Quites LV, Fonseca Filho GA. Percutaneous Foramen Ovale Puncture: Usefulness of Intraoperative CT Control, in the Eventuality of a Narrow Foramen [published online ahead of print, 2020 Sep 16]. Stereotact Funct Neurosurg. 2020;1-4. doi:10.1159/000509821
Zdilla MJ, Fijalkowski KM. The Shape of the Foramen Ovale: A Visualization Aid for Cannulation Procedures. J Craniofac Surg. 2016 Dec 23. doi: 10.1097/SCS.0000000000003325. [Epub ahead of print] PubMed PMID: 28027173.
Guo Z, Wu B, Du C, Cheng M, Tian Y. Stereotactic Approach Combined with 3D CT Reconstruction for Difficult-to-Access Foramen Ovale on Radiofrequency Thermocoagulation of the Gasserian Ganglion for Trigeminal Neuralgia. Pain Med. 2016 Sep;17(9):1704-16. doi: 10.1093/pm/pnv108. Epub 2016 Feb 13. PubMed PMID: 26874883.
Ding W, Chen S, Wang R, Cai J, Cheng Y, Yu L, Li Q, Deng F, Zhu S, Yu W. Percutaneous radiofrequency thermocoagulation for trigeminal neuralgia using neuronavigation-guided puncture from a mandibular angle. Medicine (Baltimore). 2016 Oct;95(40):e4940. PubMed PMID: 27749549; PubMed Central PMCID: PMC5059051.