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Month: February 2019
Thoracolumbar disc herniation
Thoracolumbar disc herniation
Thoracolumbar disc herniation (TLDH) is a rare and progressively disabling disorder occurring T10/T11 T11/T12, T12/L1, L1/L2 levels. It constitute about 0.25% to 5% of all lumbar degeneration diseases 1).
see also Upper Lumbar Disc Herniation.
Upper lumbar discs have been reported as only L1–L2 and L2–L3 by some authors, and by others as T12–L1, L1–L2, and L2–L3.
Most previous studies of upper lumbar disc herniations included the L1-L2, L2-L3, and L3-L4 levels. Upper lumbar disc herniations have been reported to occur with a frequency of less than 5% of all disc herniations.
Clinical features
It may cause various symptoms attributable to the polytropic neuromechanism in different levels.
Treatment
Posterior decompressive laminectomy was the most common operation of TLDH before.
Anterolateral retroperitoneal approach, anterior transthoracic approach, posterolateral, and lateral approaches are performed in discectomy with or without fusion and internal fixation. However, patients who have undergone any operation at these levels are predisposed to postoperative recurrence, neurological aggravation, and adjacent segment degeneration, and the outcomes are inferior than those in lower lumbar spine 2) 3).
Posterior approach operation is an ideal surgical technique for treatment of TLDH; the operative time, blood loss, hospitalization duration, and symptomatic improvement are favorable 4).
Complications
Surgical procedures predispose the subjects to high incidence of complications including recurrence, neurological aggravation, and adjacent segment degeneration.
Case series
Ten patients with TLDH underwent posterior approach operation in the Department of Orthopaedics, General Hospital of Jinan Military Region, from January, 2006 to December, 2015. The mean preoperative duration of clinical symptoms was 16.5 months. The clinical data including operative time, blood loss, and hospitalization duration were investigated. Furthermore, pre and postoperative neurological status was evaluated by the Modified Japanese Orthopaedic Association scale and pain by visual analog scale (VAS) scoring system.The mean operative time was 176.50 ± 20.55 minutes, the mean blood loss was 435.00 ± 89.58 mL, and the mean hospitalization length was 13.30 ± 2.97 days. All patients were followed with a mean period of 35.1 months. The mean JOA score of all patients before operation, at discharge, 3 months after operation, and at last follow-up was 6.50 ± 1.28, 7.60 ± 1.22, 8.90 ± 0.99, and 9.00 ± 0.92, respectively. The differences between the pre and postoperative JOA and VAS scores were significant (P < .05). However, the differences of JOA and VAS scores at postoperative 3 months and final follow-up were not statistically significant.Posterior approach operation is an ideal surgical technique for treatment of TLDH; the operative time, blood loss, hospitalization duration, and symptomatic improvement are favorable 5).
A retrospective analysis of 33 patients with single level TLJ disc herniations undergoing operations was performed. Medical records, operative findings, and radiologic data were assessed. TLJ was defined as the level from T11-12 to L2-3. The mean follow-up period was 21.8 months.
Mean age was 47.3 years. Affected disc levels were T11-T12 in 5 patients, T12-L1 in 2 patients, L1-L2 in 6 patients, and L2-L3 in 20 patients. Soft disc herniations were detected in 24 patients, while the remainder showed hard disc herniations such as a bony spur or calcification. Thirty-one patients presented with pain as their chief complaint and radicular pain was the most common symptom(n=14). Various neurologic deficits including upper motor neuron syndrome, lower motor neuron syndrome, and radiculopathy were observed in 27 patients and were not related to the affected levels. Twenty-four patients with lateral disc herniations or central soft disc herniations underwent partial hemilaminectomy and facetectomy, and the remaining patients(n=9) with central disc herniations or severely calcified disc herniations underwent total facetectomy and subsequent posterior fusion. There were 7 cases with complications including dural tear, mild motor and sensory deficits, and bladder and bowel dysfunction without permanent morbidities. TLJ disc herniation shows variable symptoms and signs due to its unique anatomy. It can be safely managed by the correct surgical approach as determined by the location and type of disc herniation 6).
A cohort of 63 patients with symptomatic TLDH, who had surgery was investigated. Incidences of associated Scheuermann’s disease (SD) and four radiographic signs of SD that were Schmorl’s node, irregular vertebral end plate, posterior bony avulsion of the vertebra and wedge-shaped vertebra, average thoracolumbar kyphotic angle and incidences of disc herniation at segments with and without radiographic signs of SD were examined. Data from the TLDH group were compared with 57 patients undergoing surgery for lower lumbar disc herniation (LDH, L3/4-L5/S1) in the same period.
The incidences of the four radiographic signs of SD and the incidence of associated SD were all significantly higher in the TLDH group than in the LDH group. 95.2 % of the patients in the TLDH group were diagnosed with SD (either classical SD or its atypical form). The average thoracolumbar kyphotic angle of the TLDH group was 16.9°, while that of the LDH group was 7.6° (P = 0.000). In the TLDH group, the incidences of disc herniation at segments with radiographic signs of SD were all significantly higher than at segments where no sign of SD was found.
The high proportion of associated SD and the tendency of SD’s signs to promote disc herniation in symptomatic TLDH patients suggest a close relationship between these two disorders. Symptomatic TLDH should be seen as a truly different surgical entity, that is, a special form of SD rather than just an indicator of a failing back 7).
Reports concerning MIS-TLIF at the thoracolumbar junction are rare. Thus, Wang et al., performed a retrospective analysis of the clinical outcomes of 10 patients with thoracolumbar junction disc herniation treated by MIS-TLIF between December 2007 and October 2010. The purpose of the study was to investigate the efficacy and safety of MIS-TLIF for disc herniation in the thoracolumbar junction. Clinical and radiological data were collected and analyzed. Fusion levels included T12-L1 (two patients), L1-L2 (four patients) and L2-L3 (four patients). Clinical outcome was assessed using the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI). The average follow-up period was 39.2 months, with a minimum of 24 months. The mean ± standard error of the mean of the operative time, intraoperative blood loss, and x-ray exposure were 128 ± 36 minutes, 204 ± 35 mL, and 43 ± 12 seconds, respectively. The VAS for back and leg pain decreased significantly postoperatively from 6.4 ± 2.7 to 1.5 ± 0.6 (p<0.01), and from 7.1 ± 2.4 to 1.3 ± 0.4 (p<0.01) respectively, as did the ODI from 39.3 ± 11.2 to 16.5 ± 4.7 (p<0.01). Bone fusion was observed in eight patients. There were no other major complications at last follow-up. MIS-TIF is a safe and effective procedure for disc herniation in the thoracolumbar junction. Occurrence of non-union is relatively high compared to previous findings 8).
The clinical features of 26 patients who had undergone operations for single disc herniations at T10-T11 through L2-L3 were investigated. Affected levels were as follows: 2 patients with disc herniation at T10-T11 disc, 4 patients at T11-T12, 3 patients at T12-L1, 6 patients at L1-L2, and 11 patients at L2-L3. The level of disc space of interest was confirmed with whole-spine plain roentgenograms. The caudal end of the cord was judged by magnetic resonance imaging and computed tomographic myelogram.
Two patients with T10-T11 disc herniation showed moderate lower extremity weakness, increased patellar tendon reflex, and sensory disturbance of the entire lower extremities. Three of four patients with T11-T12 disc herniation experienced lower extremity weakness, and three patients had accentuated patellar tendon reflex. Sensory disturbance was observed in the anterolateral aspect of the thigh in one patient and on the entire leg in three patients. Bowel and bladder dysfunction was noted in three patients. In the T12-L1 disc herniation group (n = 3), muscle weakness and atrophy below the leg were advanced, and bowel and bladder dysfunction were also noted. Two of these three patients had bilateral drop foot, and one patient had unilateral drop foot; sensory disturbance was noted in the sole or foot and around the circumference of the anus, and the patellar tendon reflex and Achilles tendon reflex were absent. All six patients with L1-L2 disc herniation showed severe thigh pain and sensory disturbance at the anterior aspect or lateral aspect of the thigh. On the other hand, there were no clear signs of lower extremity weakness, muscle atrophy, deep tendon reflex, or bowel and bladder dysfunction in these patients. In the L2-L3 disc herniation group (n = 11), all patients had severe thigh pain and sensory disturbance of the anterior aspect or the lateral aspect of the thigh. Weakness in the quadriceps was noted in five patients and weakness in the tibialis anterior in two patients. Decreased or absence of patellar tendon reflex was observed in nine patients. Five patients had positive straight leg raising test results, and eight patients showed positive femoral nerve stretch test results.
Among thoracolumbar junction disc herniations, T10-T11 and T11-T12 disc herniations were considered upper neuron disorders, T12-L1 disc herniations were considered lower neuron disorders, L1-L2 disc herniations were considered mild disorders of the cauda equina and radiculopathy, and L2-L3 disc herniations were considered radiculopathy. These findings had relatively distinct differences among herniated disc levels 9).
References
Supplementary Spetzler-Martin AVM grading scale
Supplementary Spetzler-Martin AVM grading scale
In 2010, Michael T. Lawton et. al introduced the Supplementary Spetzler-Martin AVM grading scale specifically to predict surgical outcomes in Ruptured cerebral arteriovenous malformation. The Supplemented Spetzler-Martin grading scale also included rupture status, age of the patient, and nidal architecture (diffuse versus focal). In the 300 patients in Lawton’s 2010 study, the supplemental Spetzler-Martin grading scale demonstrated a stronger correlation with surgical outcomes than the initial Spetzler-Martin AVM grading system (ROC 0.78 vs 0.66) 1).
This arteriovenous malformation (AVM) grading system supplements rather than replaces the well-established Spetzler-Martin AVM grading systemand is a better predictor of neurologic outcomes after AVM surgery. The supplementary grading scale has high predictive accuracy on its own and stratifies surgical risk more evenly. The supplementary grading system is easily applicable at the bedside, where it is intended to improve preoperative risk prediction and patient selection for surgery 2).
A retrospective study was conducted on 200 patients admitted to the Helsinki University Hospital between 2000 and 2014. The validity of the Supp-SM and SM grading systems was compared using the area under the receiver operating characteristic (AUROC) curves, with respect to the change between preoperative and early (3-4 mo) as well as final postoperative modified Rankin Scale (mRS) scores.
The performance of the Supp-SM was superior to that of the SM grading scale in the early follow-up (3-4 mo): AUROC = 0.57 (95% confidence interval [CI]: 0.49-0.65) for SM and AUROC = 0.67 (95% CI: 0.60-0.75) for Supp-SM. The Supp-SM performance continued improving over SM at the late follow-up: AUROC = 0.63 (95% CI: 0.55-0.71) for SM and AUROC = 0.70 (95% CI: 0.62-0.77) for Supp-SM. The perforating artery supply, which is not part of either grading system, plays an important role in the early follow-up outcome (P = .008; odds ratio: 2.95; 95% CI: 1.32-6.55) and in the late follow-up outcome (P < .001; odds ratio: 5.89; 95% CI: 2.49-13.91).
The Supp-SM grading system improves the outcome prediction accuracy and is a feasible alternative to the SMS, even for series with higher proportion of high-grade AVMs. However, perforators play important role on the outcome 3).
Data collected from 1009 AVM patients who underwent AVM resection were used to compare predictive powers of Spetzler Martin grades (SM) and supplemented Spetzler-Martin grades (SM-Supp). Patients included the original 300 patients plus those treated thereafter (N=117), and an additional 592 patients from three other centers.
In the combined cohort, the SM-Supp system performed better than SM system alone: AUROC=0.75 (95% CI: 0.71 – 0.78) for SM-Supp and AUROC=0.69 (95% CI: 0.65 – 0.73) for SM (p< 0.001). Stratified analysis fitting models within three different follow-up groupings (<6 months, 6 months – 2 years, and >2 years) demonstrated that the SM-Supp system performed better than SM system for both medium (AUROC=0.71 vs. 0.62, p=0.003) and long follow-up (AUROC=0.69 vs. 0.58, p=0.001). Patients with SM-Supp grades ≤ 6 had acceptably low surgical risks (0 – 24%), with a significant increase in risk for grades above 6 (39% – 63%).
The study of Kim et al., validates the predictive accuracy of the supplementary grading system in a multicenter cohort. SM-Supp grade of 6 is a cut-off or boundary for AVM operability. Supplemented grading is currently the best method of estimating neurological outcomes after AVM surgery, and recommended as a starting point in the evaluation of AVM operability 4).
References
Lateral lumbar interbody fusion (LLIF)
Lateral lumbar interbody fusion (LLIF)
Lateral lumbar interbody fusion (LLIF) is a minimally invasive technique first described by Ozgur et al. 1). LLIF allows the surgeon to access the intervertebral space via a minimally invasive direct lateral approach through the psoas muscle. The advantage of LLIF over the traditional anterior approach is the avoidance of exposure of the abdominal viscera, large vessels, and sympathetic plexus. Injury to the nerve roots and dura, and perineural fibrosis, which can occur after PLIF or TLIF, are minimized with this technique 2). 3).
Indications
Used to treat leg pain or back pain generally caused by degenerative disc disease.
LLIF has been utilized to treat a variety of pathologies including adult degenerative scoliosis, central and foraminal stenosis, spondylolisthesis, and adjacent segment degeneration
They have become an increasingly popular surgical technique due to the benefits of minimal tissue disruption, excellent disc visualization, ability to insert a large intervertebral cage to lessen subsidence, and faster recovery times 4) 5).
Position
The LLIF procedure differs from other lumbar procedures in that the patient is positioned in the lateral decubitus position, often times utilizing bending the bed near the iliac crest region in order to facilitate access to the L4-5 disc space.
In awake volunteers, the pressure at the iliac crest or greater trochanter at the break of the bed increases by increasing the bed angle. Women with a lower BMI had high VAS pain scores when their greater trochanter was at maximal bed break. Men with higher BMI had high VAS pain scores when their iliac crest was at maximal bed break. An awareness of the iliac crest or greater trochanter at the break of the bed should be considered to prevent pain and increased pressure based on the patient’s sex and BMI 6).
As with most minimally invasive spine procedures, lateral lumbar interbody fusion (LLIF) requires the use of biplanar fluoroscopy for localization and safe interbody cage placement. Computed tomography (CT)-based intraoperative spinal navigation has been shown to be more effective than fluoroscopic guidance for posterior-based approaches such as pedicle screw instrumentation.
Use of an intraoperative cone-beam CT with an image-guided navigation system is feasible and safe and appears to be accurate, although a larger study is required to confirm these results 7).
Complications
Cost effectiveness
TLIF and LLIF produced equivalent 2-year patient outcomes at an equivalent cost-effectiveness profile 8).
Systematic reviews
Transpsoas lateral interbody fusion is one of the Lateral Lumbar Interbody Fusion minimally invasive approaches for lumbar spine surgery. Most surgeons insert the interbody cage laterally and then insert pedicle or cortical screw and rod instrumentation posteriorly. However, standalone cages have also been used to avoid posterior instrumentation.
The literature on comparison of the two approaches is sparse.
Alvi et al., performed a systematic review and meta-analysis of the available literature on transpsoas lateral interbody fusion by an electronic search of the PubMed, EMBASE, and Scopus databases using PRISMA guidelines. They compared patients undergoing transpsoas standalone fusion (TP) with those undergoing transpsoas fusion with posterior instrumentation (TPP).
A total of 28 studies with 1462 patients were included. Three hundred and seventy-four patients underwent TPP, and 956 patients underwent TP. The mean patient age ranged from 45.7 to 68 years in the TP group, and 50 to 67.7 years in the TPP group. The incidence of reoperation was found to be higher for TP (0.08, 95% confidence interval [CI] 0.04-0.11) compared to TPP (0.03, 95% CI 0.01-0.06; p = 0.057). Similarly, the incidence of cage movement was found to be greater in TP (0.18, 95% CI 0.10-0.26) compared to TPP (0.03, 95% CI 0.00-0.05; p < 0.001). Oswestry Disability Index (ODI) and visual analog scale (VAS) scores and postoperative transient deficits were found to be comparable between the two groups.
These results appear to suggest that addition of posterior instrumentation to transpsoas fusion is associated with decreased reoperations and cage movements. The results of previous systematic reviews and meta-analysis should be reevaluated in light of these results, which seem to suggest that higher reoperation and subsidence rates may be due to the use of the standalone technique 9).
A systematic and critical review of recent literature was conducted in accordance with PRISMA guidelines. The sources of the data were PubMed, MEDLINE, Embase, Cochrane and Scopus. Key search terms were “transpsoas”, “interbody fusion”, “LLIF”, “XLIF” and “spondylolisthesis”. Papers included in the review were original research articles in peer-reviewed journals. The articles were thoroughly examined and compared on the basis of study design, outcomes, and results. Only studies which met the eligibility criteria were included. Eight studies were included in the qualitative and quantitative analysis (three retrospective, four prospective, one randomized controlled trial). A total of 308 patients (227 females) (pooled age 64.5 years) and a total of 353 operated levels were analyzed. Mean follow up time ranged from 6.2 to 24 months. There were no reported cases of durotomies or pseudarthrosis in any study. All neurologic complications were reported to be transient with no permanent deficits. Mean improvement in ODI scores ranged between 19.5 (38.6%) to 36 (54.5%). Mean improvement in slip ranged from 47 to 67.5%. Three studies also reported that patient satisfaction and willingness to undergo the procedure again approached 90%. Minimally invasive transpsoas interbody fusion possibly leads to favorable clinical and radiological outcomes while avoiding the possible complications of its more traditional open and minimally invasive counterparts. Further studies are needed to better establish its role in the management of low grade degenerative lumbar spondylolisthesis 10).
Case series
References
Poor grade aneurysmal subarachnoid hemorrhage
Poor grade aneurysmal subarachnoid hemorrhage
Poor-grade subarachnoid hemorrhage (SAH), that is, World Federation of Neurosurgical Societies grading Grades IV and V, have high morbidity and mortality rates.
A total of 104 consecutive patients with poor-grade aSAH from the Department of Neurosurgery, The Second Hospital of Shandong University, Jinan, were enrolled between January 2010 and December 2017. All these patients underwent early microsurgical clipping or endovascular coiling within three days after onset. Microsurgical clipping or endovascular coiling was selected according to aneurysm patterns, patient clinical status, interdisciplinary consultation, and the decision-making of the family. The individual prognosis was evaluated using the modified Rankin scale (mRS), while the prognostic factors were analyzed using multivariate logistic regression analysis.
There were 58 patients with grade IV aSAH and 46 patients with grade V aSAH. Microsurgical clipping was performed in 71 cases, while endovascular coiling was performed in 33 cases. According to the statistical results, microsurgical clipping was preferred by patients with CT Fishergrade III-IV, WFNS grade V, cerebral hernia, intracranial hematoma and preoperative rebleeding. At six months after onset, the overall rate of favorable outcome (mRS ≤ 2) was 36.5%. Furthermore, the favorable outcome rate was 56.9% in grade IV patients and 11.1% in grade V patients. Moreover, the univariate and multivariate logistic regression analyses revealed that CT Fisher grade I-II, WFNS grade IV and endovascular coiling were associated with a favorable prognosis, while the CT low-density area was slightly correlated to a poor prognosis.
The treatment of aSAH at the early stage by microsurgical clipping or endovascular coiling should be highlighted, especially for patients with WFNS grade IV. CT Fisher grade I-II, WFNS grade IV and endovascular coiling may predict a favorable prognosis, and the CT low-density area appeared to be a possible risk factor for poor prognosis 1).
Goldberg et al., performed a retrospective analysis of the Bernese SAH database for poor-grade (World Federation of Neurosurgical Societies grade IV and V) elderly patients (age ≥60 years) suffering from aSAH admitted to our institution from 2005 to 2017. Patients were divided into 3 age groups (60-69, 70-79, and 80-90 years). Survival analysis was performed to estimate mean survival and hazard ratios for death. Binary logarithmic regression was used to estimate the odds ratio for favorable (modified Rankin Scale score of 0-3) and unfavorable (modified Rankin Scale score of 4-6) outcome. Results- Increasing age was associated with an increasing risk of death after aSAH. The hazard ratio increased by 6% per year of age ( P<0.001; hazard ratio, 1.06; 95% CI, 1.03-1.09) and 76% per decade ( P<0.001; hazard ratio, 1.76; 95% CI, 1.35-2.29). Mean survival was 56.3±8 months (patients aged 60-69 years), 31.6±7.6 months (70-79 years), and 7.6±5.8 months (80-90 years). Unfavorable outcomes 6 to 12 months after aSAH were strongly related to older age. The odds ratio increased by 11% per year of age ( P<0.001; odds ratio, 1.11; 95% CI, 1.05-1.18) and 192% per decade ( P<0.001; odds ratio, 2.92; 95% CI, 1.63-5.26). Conclusions- Risk for death and unfavorable outcome increases markedly with older age in elderly patients with poor-grade aSAH. Despite a high initial mortality, treatment resulted in a reasonable proportion of favorable outcomes up to 79 years of age and only a small number of patients who were moderately or severely disabled 6 to 12 months after aSAH. Mean survival and proportion of favorable outcomes decreased markedly in patients older than 80 years 2).
During the period 2004-2014, 248 patients with poor-grade SAH were treated in our institution. Poor-grade SAH was defined as World Federation of Neurological Surgeons grades IV-V on admission. Data including patient characteristics, treatment modality, radiologic features, and functional neurologic outcome were assessed and further analyzed. Outcome was assessed according to the modified Rankin Scale after 6 months and stratified into favorable (modified Rankin Scale score 0-2) versus unfavorable (modified Rankin Scale score 3-6). A multivariate analysis was performed to identify predictors of functional outcome.
A favorable outcome was achieved in 24% of patients with poor-grade SAH. Patients with a favorable outcome were significantly younger (P = 0.005), harbored significantly smaller aneurysms (P = 0.004), and had a lower initial World Federation of Neurological Surgeons grade (P < 0.0001). An unfavorable outcome was significantly more frequent in patients with additional space-occupying hematoma compared with patients without additional space-occupying hematoma (P = 0.0009). On multivariate analysis, patient age, World Federation of Neurological Surgeons grade V, signs of cerebral herniation, aneurysm size, and presence of space-occupying hematoma were identified as significant predictors of unfavorable outcome in patients with poor-grade SAH.
A favorable outcome was achieved in 24% of severely ill patients with poor-grade SAH. Therefore, treatment of patients with poor-grade SAH should not be omitted. Careful individualized decision making is necessary for each patient 3).
118 patients with World Federation of Neurosurgical Societies (WFNS) grades IV and V underwent surgical treatment. Ultra-early surgery was defined as surgery performed within 24 h of aSAH, and delayed surgery as surgery performed after 24 h. Outcome was assessed by modified Rankin Scale (mRS). The mean time of follow-up was 12.5±3.4 months (range 6-28 months).
47 (40%) patients underwent ultra-early surgery, and 71 (60%) patients underwent delayed surgery. Patients with WFNS grade V (p=0.011) and brain herniation (p=0.004) more often underwent ultra-early surgery. Postoperative complications were similar in ultra-early and delayed surgery groups. Adjusted multivariate analysis showed the outcomes were similar between the two groups. Multivariate analysis of predictors of poor outcome, ultraearly surgery was not an independent predictor of poor outcome, while advanced age, postresuscitation WFNS V grade, intraventricular haemorrhage, brain herniation and non-middle cerebral artery (MCA) aneurysms were associated with poor outcome.
Although patients with WFNS grade V and brain herniation more often undergo ultra-early surgery, postoperative complications and outcomes in selected patients were similar in the two groups. Patients of younger age, WFNS grade IV, absence of intraventricular haemorrhage, absence of brain herniation and MCA aneurysms are more likely to have a good outcome. Ultra-early surgery could improve outcomes in carefully selected patients with poor-grade aSAH 4).
The purpose of a study was to undertake a single-center randomized controlled feasibility trial comparing a strategy of early endovascular aneurysm treatment with treatment after neurologic recovery in this group of patients.
Patients with poor-grade SAH were randomized within 24 hours of admission to early treatment or treatment after neurologic recovery. If a patient was randomized to early treatment, the aneurysm was treated endovascularly within 24 hours of randomization. Recruitment rate, safety profile, and functional outcome at the time of discharge and at 6 months were assessed.
Fourteen of 51 patients screened were eligible for the trial. Of these 14, 8 patients were randomized (57%). All patients in the early coiling arm received treatment within 24 hours of randomization. There was no treatment-related complication. Overall, good outcome occurred in 25% of patients; the mortality rate was 75%. Patients in the early treatment arm (n = 5) had a good outcome rate of 20%, while those in treatment after neurologic recovery arm (n = 3) had a good outcome rate of 33.3%.
This was a feasibility study that demonstrated that recruitment and randomization for comparing management strategies in poor-grade SAH are feasible. The recruitment rate among eligible patients was encouraging (57%), though a number of patients had to be excluded due to ineligibility. A multicenter study is necessary to recruit the numbers required to compare the clinical outcomes of these management strategies 5).
Timing of surgery for poor-grade aneurysmal subarachnoid hemorrhage is still controversial, therefore this study aimed to identify the optimal time to operate on patients admitted in poor clinical condition.
Ninety-nine patients meeting the inclusion criteria were randomly assigned into three treatment groups. The early surgery group received operation within 3 days after onset of subarachnoid hemorrhage (day of SAH = day 1); the intermediate surgery group received operation from days 4 to 7, and surgery was performed on the late surgery group after day 7. Follow-up was performed 1, 3, and 6 months after aneurysm clipping. Primary indicators of outcome included the Extended Glasgow Outcome Scale and the Modified Rankin Scale, while secondary indicators of outcome were assessed using the Barthel Index and mortality.
This was the first prospective, single-center, observer-blinded, randomized controlled trial to elucidate optimal timing for surgery in poor-grade subarachnoid hemorrhage patients. The results of this study will be used to direct decisions of surgical intervention in poor-grade subarachnoid hemorrhage, thus improving clinical outcomes for patients 6)
A prospective investigation was conducted in 149 patients with SAH (mean age 50.9 +/- 12.9 years); these patients were studied for 162 +/- 84 hours (mean +/- standard deviation). Lesions were classified as low-grade SAH (WFNS Grades I-III, 89 patients) and high-grade SAH (WFNS Grade IV or V, 60 patients). After approval by the local ethics committee and consent from the patient or next of kin, a microdialysis catheter was inserted into the vascular territory of the aneurysm after clip placement. The microdialysates were analyzed hourly for extracellular glucose, lactate, lactate/pyruvate (L/P) ratio, glutamate, and glycerol. The 6- and 12-month outcomes according to the Glasgow Outcome Scale and functional disability according to the modified Rankin Scale were assessed. In patients with high-grade SAH, cerebral metabolism was severely deranged compared with those who suffered low-grade SAH, with high levels (p < 0.05) of lactate, a high L/P ratio, high levels of glycerol, and, although not significant, of glutamate. Univariate analysis revealed a relationship among hyperglycemia on admission, Fisher grade, and 12-month outcome (p < 0.005). In a multivariate regression analysis performed in 131 patients, the authors identified four independent predictors of poor outcome at 12 months, in the following order of significance: WFNS grade, patient age, L/P ratio, and glutamate (p < 0.03).
Microdialysis parameters reflected the severity of SAH. The L/P ratio was the best metabolic independent prognostic marker of 12-month outcome. A better understanding of the causes of deranged cerebral metabolism may allow the discovery of therapeutic options to improve the prognosis, especially in patients with high-grade SAH, in the future 7).
A prospectively audited, nonselected series of 177 consecutive poor-grade (i.e., World Federation of Neurological Surgeons Grades IV and V) patients with aneurysmal subarachnoid hemorrhage managed during a 9-year period was analyzed. A management policy of aggressive ultraearly surgery (not selected by age or by grade) was followed. Coiling was not available. Outcomes were assessed at 3 months.
Despite the aggressive management policy, surgery could be performed in only 132 poor-grade patients (75%). Twenty percent of all patients were 70 years of age or older (15% of the surgical cases). All surgery was performed within 12 hours of subarachnoid hemorrhage (majority <6 h). Preoperative rebleeding occurred within the first 12 hours (>85% within 6 h) in 20% of the patients, which is four times the rate found in good-grade patients managed according to the same policy. Outcome assessment performed at 3 months in the 132 poor-grade surgical patients revealed that 40% were independent, 15% were dependent, and 45% had died. There was no significant difference in outcomes for young and old (70+ yr) poor-grade surgical patients (P > 0.05).
The high ultraearly rebleeding rate indicates a need to urgently secure the ruptured aneurysm by performing surgery or coiling, and this indication is more pronounced for poor-grade patients than for good-grade patients. The outcome results of ultraearly surgery indicate that a nonselective policy does not lead to a large number of dependent survivors, even among elderly poor-grade patients 8).
References
Stereotactic radiosurgery for brain metastases
Stereotactic radiosurgery for brain metastases
Management of brain metastases typically includes radiotherapy (RT) with conventional fractionation and/or stereotactic radiosurgery (SRS). However, optimal indications and practice patterns for SRS remain unclear.
Significant heterogeneity exists in target volumes for postoperative stereotactic radiosurgery.
The use of radiosurgery as a first-line or salvage treatment for brain metastases continues to expand. As a focal, highly precise treatment option, stereotactic radiosurgery (SRS) provides many benefits, including a short treatment timeline, a low probability of normal tissue complication, and a high probability of treated lesion control 1).
Kann et al. sought to evaluate national practice patterns for patients with metastatic disease receiving brain RT. They queried the National Cancer Data Base (NCDB) for patients diagnosed with metastatic non-small cell lung cancer, breast cancer, colorectal cancer, or melanoma from 2004 to 2014 who received upfront brain RT. Patients were divided into SRS and non-SRS cohorts. Patient and facility-level SRS predictors were analyzed with chi-square tests and logistic regression, and uptake trends were approximated with linear regression. Survival by diagnosis year was analyzed with the Kaplan-Meier method. Results: Of 75,953 patients, 12,250 (16.1%) received SRS and 63,703 (83.9%) received non-SRS. From 2004 to 2014, the proportion of patients receiving SRS annually increased (from 9.8% to 25.6%; P<.001), and the proportion of facilities using SRS annually increased (from 31.2% to 50.4%; P<.001). On multivariable analysis, nonwhite race, nonprivate insurance, and residence in lower-income or less-educated regions predicted lower SRS use (P<.05 for each). During the study period, SRS use increased disproportionally among patients with private insurance or who resided in higher-income or higher-educated regions. From 2004 to 2013, 1-year actuarial survival improved from 24.1% to 49.6% for patients selected for SRS and from 21.0% to 26.3% for non-SRS patients (P<.001). Conclusions: This NCDB analysis demonstrates steadily increasing-although modest overall-brain SRS use for patients with metastatic disease in the United States and identifies several progressively widening sociodemographic disparities in the adoption of SRS. Further research is needed to determine the reasons for these worsening disparities and their clinical implications on intracranial control, neurocognitive toxicities, quality of life, and survival for patients with brain metastases 2).
Complications
With increased adoption of this approach also comes an increase in incidence of treatment failure. Radiosurgical failure, either due to tumor regrowth or radiation necrosis, can occur in about 10% to 15% of patients still alive at 1 yr 3).
Radiation necrosis (RN) may occur after treatment and is challenging to distinguish from local recurrence (LR).
PET is superior to computed tomography and magnetic resonance imaging in the differentiation between recurrence and radiation reaction/necrosis. However, temporary radiation effects may mask remaining tumor tissue, and repeat PET studies may sometimes be necessary 4).
There are a variety of salvage options available for patients with brain metastases who experience local failure after stereotactic radiosurgery (SRS). These options include resection,whole brain radiation therapy, laser interstitial thermotherapy, and repeat SRS. There is little data on the safety and efficacy of repeat SRS following local failure of a prior radiosurgical procedure.
Systematic Reviews
2017
Using Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, a systematic review was conducted using PubMed and Medline up to November 2016. A separate search was conducted for SRS for larger brain metastases.
Twenty-seven prospective study, critical reviews, metaanalysis, and published consensus guidelines were reviewed. Four key points came from these studies. First, there is no detriment to survival by withholding whole brain radiation (WBRT) in the upfront management of brain metastases with SRS. Second, while SRS on its own provides a high rate of local control (LC), WBRT may provide further increase in LC. Next, WBRT does provide distant brain control with less need for salvage therapy. Finally, the addition of WBRT does affect neurocognitive function and quality of life more than SRS alone. For larger brain metastases, surgical resection should be considered, especially when factoring lower LC with single-session radiosurgery. There is emerging data showing good LC and/or decreased toxicity with multisession radiosurgery.
A number of well-conducted prospective and meta-analyses studies demonstrate good LC, without compromising survival, using SRS alone for patients with a limited number of brain metastases. Some also demonstrated less impact on neurocognitive function with SRS alone. Practice guidelines were developed using these data with International Stereotactic Radiosurgery Society consensus 5).
Stereotactic radiosurgery (SRS) offers excellent local control for brain metastases (BM) with low rates of toxicity.
It avoids whole brain radiotherapy (WBRT)-associated morbidity.
Studies have clearly established the safety and efficacy of single-dose SRS. However, as patient survival has increased, the recurrence of tumors and the development of metastases to new sites within the brain have made it desirable to repeat treatments over time. The cumulative toxicity of multi-isocenter, multiple treatments has not been well defined.
Postoperative stereotactic radiosurgery to the resection cavity safely and effectively augments local control of large brain metastases. Patients with <4 metastases and controlled systemic disease have significantly lower rates of distant brain failure (DBF) and are ideal treatment candidates 6).
In patients with limited brain metastases from non small cell lung cancer (NSCLC), SRS is an effective treatment associated with high local control rate with low morbidity. When performed in isolation, close follow-up is mandatory and radiosurgery can be renewed as salvage treatment for distant brain progression, limiting the use of WBRT 7).
Significant tumor volume reduction by 6 or 12 weeks post-SRS was associated with long-term local control.
For patients at low risk of distant intracranial failure (such as those with systemic disease control) with early, robust volumetric response, it may reasonable to lengthen imaging intervals to maximize clinical utility.
Although it is necessary to validate the findings in a larger, prospective series, the results are encouraging that a robust early volumetric response is associated with sustained local control for metastatic brain lesions 8).
Gamma Knife radiosurgery (GKRS) offers a high rate of tumor control and good survival benefits in both new and recurrent patients with MBT. Thus, GKRS is an effective treatment option for new patients with MBT, as well as an adjuvant therapy in patients with recurrent MBT. 9) 10).
There appears to be no consensus regarding the optimal treatment strategy among patients with >3 brain metastases, and practice patterns are heterogeneous. Radiation oncologists, especially high-volume CNS specialists, are treating significantly more brain metastases with SRS than what currently is recommended by published consensus guidelines. Providers struggle with patients with a moderate intracranial disease burden. Further prospective studies are needed to support these practice patterns and guide decision making 11).
Case series
Patients (n = 41) undergoing single-fraction Gamma Knife SRS following surgical resection of brain metastases from 2011 to 2017 were retrospectively reviewed. SRS included the entire contrast-enhancing cavity with heterogeneity in inclusion of the surgical tract and no routine margin along the dura or clinical target volume margin. Follow-up MR imaging was fused with SRS plans to assess patterns of failure.
The median follow-up was 11.1 months with a median prescription of 18 Gy. There were 5 local failures: infield (n = 3, 60%), surgical tract (n = 1, 20%), and marginal > 5 mm from the resection cavity (n = 1, 20%). No marginal failures < 5 mm or dural margin failures were noted. For deep lesions (n = 13), 62% (n = 8) had the entire tract covered. The only tract recurrence was in a deep lesion without coverage of the surgical tract (n = 1/5).
In this small preliminary experience, despite no routine inclusion of the dural tract or bone flap, no failures were noted in these locations. Omission of the surgical tract in deep lesions may increase failure rates 12).
References
Intracranial atherosclerosis
Intracranial atherosclerosis
see Large artery atherosclerosis
see Carotid artery atherosclerotic disease.
Intracranial atherosclerosis related large vessel occlusions (ICAS-O) are challenging to diagnose and manage. The degree of intracranial carotid artery calcification may assist pre-thrombectomy diagnosis of ICAS and guide treatment strategy.
The aim of a study was to report the relationship between cognitive function and risk factors at baseline and during follow-up in the Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) trial.
Subjects in the SAMMPRIS trial were included in this study. In order to have an assessment of cognitive function independent of stroke, patients with a stroke as a qualifying event whose deficits included aphasia or neglect were excluded from these analyses as were those with a cerebrovascular event during follow-up. The Montreal Cognitive Assessment (MoCA) score was used to assess cognitive impairment at baseline, 4 months, 12 months and closeout. Cognitive impairment was defined as MoCA < 26. A multivariate analysis was performed to determine what risk factors were independent predictors of cognitive function at baseline, 12 months and closeout. Among patients randomized to aggressive medical management only, the percentage of patients with cognitive impairment was compared between patients in versus out of target for each risk factor at 12 months and closeout.
Of the 451 patients in SAMMPRIS, 371 patients met the inclusion criteria. MoCA < 26 was present in 55% at baseline. Older age and physical inactivity were associated with cognitive impairment at baseline. Older age, non-white race, lower baseline body mass index, and baseline cognitive impairment were associated with cognitive impairment at 12 months. In the aggressive medical management group, at 12 months, physical inactivity during follow-up was the strongest risk factor associated with cognitive impairment.
Cognitive impairment is common in patients with severe symptomatic intracranial atherosclerosis. Physical inactivity at baseline and during follow-up is a strong predictor of cognitive impairment 1).
A study investigated whether inhalation of fine airborne particulate matters (PM2.5) causes ICA and whether omega-3 fatty acids (O3FA) attenuated the development of ICA.
Twelve but not 6 week exposure significantly increased triglycerides (TG) in normal chow diet (NCD), while PM2.5 enhanced all lipid profiles (TG, low density lipoprotein (LDL) and cholesterol (CHO)) after both 6 and 12-week exposure with high-cholesterol diet (HCD). PM2.5 exposure for 12 but not 6 weeks significantly induced middle cerebral artery (MCA) narrowing and thickening, in association with the enhanced expression of inflammatory cytokines, (interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), interferon gamma (IFN-γ)), vascular cell adhesion molecule 1 (VCAM-1) and inducible nitric oxide synthase (iNOS). O3FA significantly attenuated vascular alterations, even without favorable changes in lipid profiles, in association with reduced expression of IL-6, TNF-α, MCP-1, IFN-γ, VCAM-1 and iNOS in brain vessels.
PM2.5 exposure for 12 weeks aggravates ICA in a dietary model (HCD + short-term L-NAME), which may be mediated by vascular inflammation. O3FA dietary supplementation prevents ICA development and inflammatory reaction in cerebral vessels.
Adult Sprague-Dawly rats were under filtered air (FA) or PM2.5 exposure with NCD or HCD for 6 or 12 weeks. Half of the HCD rats were treated with O3FA (5 mg/kg/day) by gavage. A total of 600 mg NG-nitro-L-arginine methyl ester (L-NAME, 3 mg/mL) per rat was administered over two weeks as supplementation in the HCD group. Blood lipids, including LDL, CHO, TG and high density lipoprotein (HDL), were measured at 6 and 12 weeks. ICA was determined by lumen diameter and thickness of the MCA. Inflammatory markers, IL-6, TNF-α, MCP-1, IFN-γ, VCAM-1 and iNOS were assessed by real-time PCR for mRNA and Western blot for protein expression 2).
References
Welcome to European Spine Review & Cadaver Cource 2019
https://www.cervicalspine2019.com/
Dear colleagues and friends,
It is my great pleasure to announce the “European Spine Review and Cadaver Course: Part 1 Cervical Spine” which will be held in Athens, Greece, in February 2019.
The workshop brings together spine specialists to hear research and discuss topics related to the treatment of cervical spinal disorders. Examine topics important to your practice, evaluate the latest research.
In Athens February 15 – 16, 2019, we will provide comprehensive lectures given by international experts, intensive discussions between participants and faculty members, and a special cadaver workshop for practicing approaches and new techniques in pain management and in cervical spine surgery.
We are looking forward to welcome neurosurgeons, orthopedic surgeons, spine surgeons and researchers from all over the world.
Ioannis Polythodorakis, M.D.,
Chairman of European Spine Review and Cadaver Course
President World Spinal Column Society
Cranial nerve tractography
Cranial nerve tractography
Diffusion imaging tractography caught the attention of the scientific community by describing the white matter architecture in vivo and noninvasively, but its application to small structures such as cranial nerves remains difficult. The few attempts to track cranial nerves presented highly variable acquisition and tracking settings.
A “targeted” review of the scientific literaturewas carried out using the MEDLINEdatabase.
Jacquesson et al., selected studies that reported how to perform the tractography of cranial nerves, and extracted the following: clinical context; imaging acquisition settings; tractography parameters; regions of interest (ROIs) design; and filtering methods.
Twenty-one published articles were included. These studied the optic nerves in suprasellar tumors, the trigeminal nerve in neurovascular conflicts, the facial nerve position around vestibular schwannomas, or all cranial nerves. Over time, the number of MRI diffusion gradient directions increased from 6 to 101. Nine tracking software packages were used which offered various types of tridimensional display. Tracking parameters were disparately detailed except for fractional anisotropy, which ranged from 0.06 to 0.5, and curvature angle, which was set between 20° and 90°. ROI design has evolved towards a multi-ROI strategy. Furthermore, new algorithms are being developed to avoid spurious tracts and improve angular resolution.
This review highlights the variability in the settings used for cranial nerve tractography. It points out challenges that originate both from cranial nerve anatomy and the tractography technology, and allows a better understanding of cranial nerve tractography 1).
Case series
Five neurologically healthy adults and 3 patients with brain tumors were scanned with diffusion spectrum imaging that allowed high-angular-resolution fiber tracking. In addition, a 488-subject diffusion magnetic resonance imaging template constructed from the Human Connectome Project data was used to conduct atlas space fiber tracking of CNs.
The cisternal portions of most CNs were tracked and visualized in each healthy subject and in atlas fiber tracking. The entire optic radiation, medial longitudinal fasciculus, spinal trigeminal nucleus/tract, petroclival portion of the abducens nerve, and intrabrainstem portion of the facial nerve from the root exit zone to the adjacent abducens nucleus were identified. This suggested that the high-angular-resolution fiber tracking was able to distinguish the facial nerve from the vestibulocochlear nerve complex. The tractography clearly visualized CNs displaced by brain tumors. These tractography findings were confirmed intraoperatively.
Using high-angular-resolution fiber tracking and atlas-based fiber tracking, we were able to identify all CNs in unprecedented detail. This implies its potential in localization of CNs during surgical planning 2).
Videos
Visualization of Cranial Nerves Using High-Definition Fiber Tractography