Author: cba

Posted on

The complete anterior petrosectomy: an expanded extended-middle fossa approach with removal of the infratrigeminal petrous apex and drilling of the lateral clivus

J Neurosurg 141:195–203, 2024

Intradural exposure in the extended middle fossa anterior transpetrosal approach is traditionally limited to the inferior petrosal sinus inferomedially. Expanding bone removal of the petrous apex around the petrous internal carotid artery (ICA), underneath the trigeminal ganglion/mandibular nerve, and into the lateral component of the clivus can significantly expand the limits of this approach beyond the inferior petrosal sinus and allows for exposure of the midline structures, aspects of the contralateral inferior clival region, and, when high riding, the vertebrobasilar junction.

To date, no descriptive techniques for drilling into the lateral clivus in this approach have been published. The authors provide a detailed stepwise description of their complete anterior petrosectomy, in use at their institution, that involves skeletonization of the posteromedial petrous ICA, gentle elevation of the trigeminal ganglion/mandibular nerve, removal of the infratrigeminal petrous apex, and two techniques for drilling into the lateral clivus along the petroclival fissure.

These techniques provide a direct and unobstructed corridor to the midpetroclival region and ventral brainstem with greater maneuverability and enhanced control of the midline structures, which is especially useful for resection of petroclival meningiomas, chondrosarcomas, and giant vascular lesions of the mid- and upper basilar artery and its proximal branches.

Posted on

Intra‑operative hypertension as a predictor of surgical outcomes in microvascular decompression surgery for trigeminal neuralgia

Acta Neurochirurgica (2024) 166:297

The trigeminocardiac reflex (TCR) has traditionally been characterized by a sudden decrease in heart rate, asystole, or hypotension during the manipulation of the trigeminal nerve (MTN) or its branches. While this classical TCR is well-documented, there is limited literature on alternative forms of TCR, such as the development of intraoperative hypertension (HTN) or tachycardia, and the underlying pathogenesis. Furthermore, a gap exists in understanding the correlation between intraoperative blood pressure readings and postoperative outcomes, particularly regarding pain relief in patients with trigeminal neuralgia (TN). Our study aims to examine intraoperative blood pressure trends during microvascular decompression (MVD) for TN and assess their impact on postoperative outcomes.

Methods We selected 90 patients who underwent MVD for TN treatment. Blood pressure and heart rate were recorded both preoperatively and during the procedure, specifically during the MTN period, using an arterial line. The Barrow Neurological Institute (BNI) Pain Scale was calculated for all patients both pre- and post-operatively to evaluate pain relief after surgery.

Results The mean age of the patients was 61.0 ± 12.35 years, with 64.4% being females. Classical TCR (hypotension) was observed in only 2.2% of patients, whereas 80% of patients developed hypertension (≥ 140/90) during MTN. The mean preoperative systolic blood pressure was 128 ± 22.25, and the mean intraoperative systolic blood pressure during MTN was 153.1 ± 20.2. An analysis of covariance, utilizing either preoperative BNI or duration of symptoms as covariate variables, revealed a statistically significant association between intraoperative HTN and postoperative BNI. A linear regression model demonstrated that intraoperative HTN following MTN significantly predicted a lower postoperative BNI score (p = 0.006).

Conclusions Intraoperative HTN during MTN, an observed yet underexplored phenomenon, demonstrated a correlation with improved postoperative outcomes. Furthermore, it is recommended to conduct additional investigations into potential neurovascular conflicts in patients not manifesting intraoperative HTN following MTN. A comprehensive understanding of TCR, encompassing its various forms, is vital for optimizing surgical management. This study underscores the imperative for further research to unravel the mechanisms linking intraoperative HTN to surgical outcomes in TN patients.

Posted on

Comparing posterior cervical foraminotomy with anterior cervical discectomy and fusion in radiculopathic patients: an analysis from the Quality Outcomes Database

J Neurosurg Spine 41:56–68, 2024

OBJECTIVE The objective of this study was to compare clinical and patient-reported outcomes (PROs) between posterior foraminotomy and anterior cervical discectomy and fusion (ACDF) in patients presenting with cervical radiculopathy.

METHODS The Quality Outcomes Database was queried for patients who had undergone ACDF or posterior foraminotomy for radiculopathy. To create two highly homogeneous groups, optimal individual matching was performed at a 5:1 ratio between the two groups on 29 baseline variables (including demographic characteristics, comorbidities, symptoms, patient-reported scores, underlying pathologies, and levels treated). Outcomes of interest were length of stay, reoperations, patient-reported satisfaction, increase in EQ-5D score, and decrease in Neck Disability Index (NDI) scores for arm and neck pain as long as 1 year after surgery. Noninferiority analysis of achieving patient satisfaction and minimal clinically important difference (MCID) in PROs was performed with an accepted risk difference of 5%.

RESULTS A total of 7805 eligible patients were identified: 216 of these underwent posterior foraminotomy and were matched to 1080 patients who underwent ACDF. The patients who underwent ACDF had more underlying pathologies, lower EQ-5D scores, and higher NDI and neck pain scores at baseline. Posterior foraminotomy was associated with shorter hospitalization (0.5 vs 0.9 days, p < 0.001). Reoperations within 12 months were significantly more common among the posterior foraminotomy group (4.2% vs 1.9%, p = 0.04). The two groups performed similarly in PROs, with posterior foraminotomy being noninferior to ACDF in achieving MCID in EQ-5D and neck pain scores but also having lower rates of maximal satisfaction at 12 months (North American Spine Society score of 1 achieved by 65.2% posterior foraminotomy patients vs 74.6% of ACDF patients, p = 0.02).

CONCLUSIONS The two procedures were found to be offered to different populations, with ACDF being selected for patients with more complicated pathologies and symptoms. After individual matching, posterior foraminotomy was associated with a higher reoperation risk within 1 year after surgery compared to ACDF (4.2% vs 1.9%). In terms of 12-month PROs, posterior foraminotomy was noninferior to ACDF in improving quality of life and neck pain. The two procedures also performed similarly in improving NDI scores and arm pain, but ACDF patients had higher maximal satisfaction rates.

Posted on

Basal vein of Rosenthal classification: the key to venous outflow of the deep sylvian fissure

J Neurosurg 141:154–164, 2024

Mastery of sylvian fissure dissection is essential to access lesions within the deep basal cisterns. The deep sylvian vein and its tributaries play a major role during access to and beyond the carotid cistern through the sylvian fissure and determine the complexity of microdissection. Preserving the venous outflow during sylvian fissure dissection is the best reliable strategy to prevent postoperative venous strokes or venous hypertension. The authors report the role of the basal vein of Rosenthal (BVR) in the venous outflow pattern of the deep sylvian cistern.

METHODS The authors analyzed 262 consecutive surgical cases involving sylvian fissure dissection from 2015 to 2017. Inclusion criteria were complete sylvian fissure dissection for the treatment of intracranial aneurysms. Exclusion criteria were giant size (aneurysm diameter > 24 mm), meningitis, subarachnoid hemorrhage within the sylvian cistern, absence of 4D CT angiography, and previous surgery. Retrospective radiological and operative video reviews were carried out to assess the association between the superficial sylvian vein and the BVR. The authors analyzed the course of the BVR and the patterns of venous drainage of the sylvian cistern. The surgical difficulty of sylvian fissure dissection was rated by the authors to study the operative significance of the venous patterns encountered. Two clinical cases are described to illustrate the proposed BVR classification.

RESULTS A total of 97 patients met the selection criteria. The most frequent type of BVR was immature (diameter < 0.5 mm, 68%). When the BVR was incompletely developed or absent (immature type), the deep sylvian veins drained through a middle sylvian vein in 70% of cases, requiring advanced sylvian fissure dissection techniques. However, when the BVR was completely developed (32%), the middle sylvian vein was found in a minority of cases (6%), which allowed for an unobstructed transsylvian corridor. Interrater and test-retest reliability of the surgical difficulty was greater than 0.9.

CONCLUSIONS Preoperative assessment of the BVR anatomy is key to predict the deep sylvian venous pattern. The authors provide objective evidence supporting the reciprocal relationship between the type of BVR and the presence of a middle sylvian vein and the deep sylvian venous outflow. An immature BVR should alert the neurosurgeon of the high likelihood of finding a complex deep venous pattern, which may drive surgical planning.

Posted on

A taxonomy for superficial cerebral cavernous malformations: subtypes of cortical and subcortical lesions

J Neurosurg 141:123–137, 2024

A taxonomy for superficial cerebral cavernous malformations (CMs), those based cortically in gyral gray matter or subcortically in underlying white matter, is proposed to build on the comprehensive, systematic characterization of CMs in the entire brain.

METHODS Patients with superficial cerebral CMs were retrospectively analyzed from a consecutive surgical series between November 2008 and June 2021 at the authors’ center. Superficial cerebral CMs were categorized into 4 subtypes based on their cortical location or, if subcortical, proximity to the nearest cerebral surface: convexity, medial, basal, and sylvian. Lobar location was also included for subtyping: frontal, temporal, parietal, and occipital.

RESULTS A total of 362 CMs were resected in 346 patients. CM subtypes were as follows: 132 (36.5%) convexity, 78 (21.5%) medial, 72 (19.9%) basal, and 80 (22.1%) sylvian. Frontal CMs were most common (155 [42.8%]), followed by parietal (89 [24.6%]), temporal (87 [24.0%]), and occipital (31 [8.6%]). Of all CMs, 302 (83.4%) were cortical and 60 (16.6%) were subcortical. The mean subcortical depth of deep lesions was 2.97 cm, and the mean lesion volume was 4.68 cm 3 . Overall, 228 lesions (63.0%) were resected through a transgyral approach, and 134 (37.0%) were resected through a transsulcal approach. Good outcomes (modified Rankin Scale [mRS] score ≤ 2) were observed in 314 patients (86.7%) and poor outcomes (mRS score > 2) in 25 patients (6.9%), and 23 patients (6.4%) were lost to late follow-up (mean follow-up duration 11.5 months). Relative outcomes were good (unchanged or improved mRS score) in 327 patients (90.3%) and poor (worse or died) in 35 patients (9.7%).

CONCLUSIONS Superficial cerebral CMs were resected through a gyrus or sulcus to open the subarachnoid dissection corridors, traversing the full extent of sulci to deepen the approach and minimize tissue transgression. Transgyral dissection avoids associated arteries but is inherently transgressive, whereas transsulcal dissection preserves cortical tissue and may reduce morbidity. Superficial cerebral CMs occupy the largest territory of the 7 types, and the size and surface complexity of the cerebrum make taxonomic subtyping valuable for clear anatomical description.

Posted on

Treatment of conus medullaris arteriovenous malformation: the role of microsurgical treatment

J Neurosurg Spine 41:115–121, 2024

Conus medullaris arteriovenous malformation (AVM) is rare and challenging to treat. To better define the presentation, prognosis, and optimal treatment of these lesions, the authors present their treatment experiences for conus medullaris AVM.

METHODS Eleven patients with AVM of the conus medullaris were identified between March 2013 and December 2021. Among these patients, 7 who underwent microsurgical treatment were included. Patient data, including age, sex, symptoms at presentation, neurological status, radiological findings, nidus depth (mainly pial lesion vs intramedullary lesion), type of treatment, and recurrence at follow-up, were collected. Postoperative angiography was performed in all patients. Spinal cord function was evaluated using the Frankel grade at the time of admission and 1 year after surgery.

RESULTS All 7 patients presenting with myeloradiculopathy were treated surgically. Four patients (57.1%) underwent endovascular embolization, followed by resection. The other 3 patients underwent microsurgery only. Complete occlusion was confirmed with postoperative angiography in all patients. Of the 3 patients who were nonambulatory before surgery (Frankel grade C), 2 were able to walk after surgery (Frankel grade D) and 1 remained nonambulatory (Frankel grade C) at 1-year follow-up.

CONCLUSIONS Based on the authors’ clinical experiences, the results of multimodal treatment for conus medullaris AVM are good, with microsurgical treatment playing an important role. The microsurgical strategy can differ depending on the location of the nidus, and when possible, good results can be expected through microsurgical resection.

Posted on

Development and validation of an artificial intelligence model to accurately predict spinopelvic parameters

J Neurosurg Spine 41:88–96, 2024

Achieving appropriate spinopelvic alignment has been shown to be associated with improved clinical symptoms. However, measurement of spinopelvic radiographic parameters is time-intensive and interobserver reliability is a concern. Automated measurement tools have the promise of rapid and consistent measurements, but existing tools are still limited to some degree by manual user-entry requirements. This study presents a novel artificial intelligence (AI) tool called SpinePose that automatically predicts spinopelvic parameters with high accuracy without the need for manual entry.

METHODS SpinePose was trained and validated on 761 sagittal whole-spine radiographs to predict the sagittal vertical axis (SVA), pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), lumbar lordosis (LL), T1 pelvic angle (T1PA), and L1 pelvic angle (L1PA). A separate test set of 40 radiographs was labeled by four reviewers, including fellowship-trained spine surgeons and a fellowship-trained radiologist with neuroradiology subspecialty certification. Median errors relative to the most senior reviewer were calculated to determine model accuracy on test images. Intraclass correlation coefficients (ICCs) were used to assess interrater reliability.

RESULTS SpinePose exhibited the following median (interquartile range) parameter errors: SVA 2.2 mm (2.3 mm) (p = 0.93), PT 1.3° (1.2°) (p = 0.48), SS 1.7° (2.2°) (p = 0.64), PI 2.2° (2.1°) (p = 0.24), LL 2.6° (4.0°) (p = 0.89), T1PA 1.1° (0.9°) (p = 0.42), and L1PA 1.4° (1.6°) (p = 0.49). Model predictions also exhibited excellent reliability at all parameters (ICC 0.91–1.0).

CONCLUSIONS SpinePose accurately predicted spinopelvic parameters with excellent reliability comparable to that of fellowship-trained spine surgeons and neuroradiologists. Utilization of predictive AI tools in spinal imaging can substantially aid in patient selection and surgical planning.

Posted on

Risk factors for vascular injuries in anterior lumbar interbody fusion

J Neurosurg Spine 41:17–23, 2024

Vascular injuries in anterior lumbar interbody fusion (ALIF) occur due to the vascular manipulation needed to achieve optimal disc space exposure. In this study, the authors aimed to evaluate intraoperative vascular injuries in patients undergoing single- and multilevel ALIF at a large tertiary academic center.

METHODS Prospectively collected data specifically addressing postoperative complications in patients who underwent ALIF by neurosurgery spine faculty working with a specialized vascular surgeon were retrospectively reviewed. Demographic characteristics and intraoperative data were collected. Patients were split into vascular injury and non–vascular injury groups. Outcome comparisons were conducted using the chi-square exact and Wilcoxon rank-sum tests for categorical and continuous data, respectively. Logistic regression was used to investigate associations with vascular injury, with univariate analysis first conducted to identify candidate associations. Based on these results, variables demonstrating a between-groups test statistic of p < 0.10 were included in the multivariate analysis to determine the independent predictors of vascular injuries.

RESULTS In total, 323 patients who underwent ALIF procedures were identified: 51% were male (n = 166) and 49% were female (n = 157). The mean age was 57.1 years, with 56% (n = 182) having undergone prior lumbar surgery. Vascular injuries were encountered intraoperatively in 7.1% (n = 23) of patients, and the majority (91% [n = 21]) involved the left common iliac vein. Patients with vascular injuries were statistically older (mean 63.6 vs 56.6 years), had greater incidence rates of coronary artery disease, opioid use, multilevel ALIF surgery involving the L2–3 level, and surgery involving multiple disc spaces, had more multilevel anterior instrumentation, and experienced greater blood loss during surgery and longer length of stay (all p < 0.05). Overall, there was 1 death (0.3%) secondary to aortic artery injury. Multivariate analysis identified opioid use, multilevel ALIF involving L2–3, and multiple interbodies as statistically independent predictors of vascular injury (all p < 0.05).

CONCLUSIONS Identifying patient risk factors can reduce the risk of vascular injuries in ALIF. Opioid use, multilevel ALIF involving L2–3, and multiple interbodies were independent predictors of vascular injuries in ALIF.

Posted on

Spinal Anterior Dural Dissection: Moving From Differential to Unifying Diagnosis

Neurosurgery 95:207–214, 2024

Cerebrospinal fluid (CSF) collections extending longitudinally at the anterior aspect of the spinal dura have been reported in association with various conditions and under multiple names. The aim of this study was to report cases associated with brachial amyotrophy (BA) and examine its relationship with other clinical variants.

METHODS: We conducted a retrospective cohort study including patients who presented with a motor deficit of the upper limbs and an anterior interdural CSF collection on spinal MRI. We performed a systematic review of the literature to include cases revealed by BA.

RESULTS: Seven patients presenting with BA and a confirmed dural dissection on spinal MRI were included. All patients were male with a slowly progressing history of asymmetrical and proximal motor deficit of the upper limbs. Chronic denervation affecting mostly C5 and C6 roots was found on electroneuromyography. Spinal MRI demonstrated an anterior CSF collection dissecting the interdural space and exerting a traction on cervical motor roots. Dynamic computed tomography myelogram localized the dural defect every time it was performed (4/7 cases), and surgical closure was possible for 3 patients, leading to resolution of the collection. Literature review yielded 18 other published cases of spinal dural dissections revealed by BA, including 4 in association with spontaneous intracranial hypotension and 4 others in association with superficial siderosis.

CONCLUSION: We propose a unifying diagnosis termed “spinal anterior dural dissection” (SADD) to encompass spinal dural CSF collections revealed by BA (SADD-BA), spontaneous intracranial hypotension (SADD-SIH), or superficial siderosis (SADD-SS).

Posted on

Clinical outcome after surgical management of spontaneous spinal epidural hematoma

Acta Neurochirurgica (2024) 166:277

Spontaneous spinal epidural hematoma (SSEH) is a rare pathology characterized by a hemorrhage in the spinal epidural space without prior surgical or interventional procedure. Recent literature reported contradictory findings regarding the clinical, radiological and surgical factors determining the outcome, hence the objective of this retrospective analysis was to re-assess these outcome-determining factors.

Methods Patients surgically treated for SSEH at our institution from 2010 – 2022 were screened and retrospectively assessed regarding management including the time-to-treatment, the pre-and post-treatment clinical status, the radiological findings as well as other patient-specific parameters. The outcome was assessed using the modified McCormick Scale. Statistical analyses included binary logistic regression and Fisher’s exact test.

Results In total, 26 patients (17 men [65%], 9 women [35%], median age 70 years [interquartile range 26.5]) were included for analysis. The SSEHs were located cervically in 31%, cervicothoracically in 42% and thoracically in 27%. Twenty-four patients (92%) improved after surgery. Fifteen patients (58%) had a postoperative modified McCormick Scale grade of I (no residual symptoms) and 8 patients (31%) had a grade of II (mild symptoms). Only 3 (12%) patients remained with a modified McCormick Scale grade of IV or V (severe motor deficits / paraplegic). Neither time-to-treatment, craniocaudal hematoma expansion, axial hematoma occupation of the spinal canal, anticoagulation or antiplatelet drugs, nor the preoperative clinical status were significantly associated with the patients’ outcomes.

Conclusion Early surgical evacuation of SSEH generally leads to favorable clinical outcomes. Surgical hematoma evacuation should be indicated in all patients with symptomatic SSEH.

Posted on

Intraorbital Arteriovenous Fistulas: Case Series and Systematic Review

Operative Neurosurgery 27:23–30, 2024

Intraorbital arteriovenous fistulas (AVFs) are an extremely rare subtype of intracranial fistula with ophthalmic symptoms similar to cavernous sinus dural AVFs or carotid cavernous fistulas but worse visual outcomes. Here, we present a case series and thorough systematic review on intraorbital AVFs to demonstrate treatment modalities and address this rare type of AVF.

METHODS: We conducted a retrospective study at a single center, in which we identified all cases of intraorbital AVFs that occurred between 2002 and 2022. We collected and analyzed data on demographics, fistula characteristics, treatment methods, clinical outcomes, and fistula closure. In addition, we conducted a systematic review of intraorbital AVFs.

RESULTS: Seven cases in our center and 41 cases of intraorbital AVFs reported in the 35 articles were identified. At our center, transarterial embolization (TAE) (42.9%) alone resulted in immediate complete occlusion in 3 cases. Transvenous embolization (14.3%) resulted in one case of immediate complete occlusion. In 2 cases, surgery (28.6%) resulted in immediate complete occlusion. In one case, conservative treatment (14.3%) was used, and the fistula was eventually spontaneously occluded. Immediate complete occlusion rate was 85.7%. One blindness occurred (14.3%). In the literature reported, 3 cases (60%) of retinal artery occlusion were reported when performing TAE via the ophthalmic artery. Two fistulas recurred as reported. In 33 (80.5%) patients, the fistula was finally completely occluded.

CONCLUSION: TAE via the ophthalmic artery carries a high risk of blindness and a low cure rate. Transvenous techniques such as conventional transvenous routes, surgical exposure, or direct puncture of the drainage vein have been used as the first line of treatment for intraorbital AVFs.

Posted on

Impact of bilateral facet joint violation on radiographic degeneration of superior adjacent segments and clinical outcomes

J Neurosurg Spine 41:1–8, 2024

Facet joint violation (FJV) is associated with postoperative low-back pain and is a confirmed risk factor for adjacent-segment degeneration, a long-term complication of lumbar fusion surgery. The authors’ knowledge of its mechanisms comes from in vitro biomechanical research only; there is a lack of radiographic evidence of the effects of violation on the superior adjacent-segment facet joint, intervertebral disc, and other local radiographic parameters. Furthermore, any differences between unilateral and bilateral violation remain relatively unclear. The authors therefore aimed to explore the effects of nonviolation and unilateral and bilateral violation on radiographic degeneration of the facet joint and intervertebral disc at the fusion and superior adjacent segment. Patient-reported clinical outcomes were compared at the 2-year follow-up.

METHODS The authors retrospectively analyzed data from 148 patients with lumbar degenerative diseases who underwent single-segment minimally invasive transforaminal lumbar interbody fusion between 2016 and 2020. FJV and facet joint degeneration were evaluated and graded using Shah’s method and Pathria’s standard, respectively. Radiographic parameters, including disc height and intervertebral Cobb angle at the fusion and superior adjacent segment, were measured. Clinical outcomes were evaluated using visual analog scale (VAS) and Japanese Orthopaedic Association scores.

RESULTS Preoperative data were comparable among the 3 groups (nonviolation, unilateral violation, and bilateral violation) (p > 0.05). Patient-reported clinical outcomes were followed up for at least 2 years (average duration 28.17 ± 6.17 months). At the last follow-up, facet joint degeneration grades were sequentially increased in the nonviolation, unilateral violation, and bilateral violation groups (p = 0.006). The unilateral (2.45 ± 2.17 mm) and bilateral (2.70 ± 1.94 mm) violation groups had more severe losses of disc height in the superior adjacent segment than did the nonviolation group (1.31 ± 2.01 mm). The VAS low-back pain and Japanese Orthopaedic Association scores in the bilateral (2.57 ± 1.44 and 19.83 ± 2.84, respectively) and unilateral (2.26 ± 0.79 and 20.43 ± 3.85, respectively) violation groups were significantly worse than in the nonviolation group (1.69 ± 1.12 and 21.80 ± 3.36, respectively) (p < 0.05). By contrast, there were no significant between-group differences in disc height, intervertebral Cobb angle in the fusion segment, or VAS leg pain scores (p > 0.05).

CONCLUSIONS FJV was associated with postoperative low-back pain and worse functional outcomes. It also aggravated facet joint and intervertebral disc changes in the superior adjacent segment, especially when bilateral violation occurred; this may be part of the mechanisms of adjacent-segment degeneration.

Posted on

Interactive microsurgical anatomy education using photogrammetry 3D models and an augmented reality cube

J Neurosurg 141:17–26, 2024

This study sought to assess the use of an augmented reality (AR) tool for neurosurgical anatomical education.

METHODS Three-dimensional models were created using advanced photogrammetry and registered onto a handheld AR foam cube imprinted with scannable quick response codes. A perspective analysis of the cube anatomical system was performed by loading a 3D photogrammetry model over a motorized turntable to analyze changes in the surgical window area according to the horizontal rotation. The use of the cube as an intraoperative reference guide for surgical trainees was tested during cadaveric dissection exercises. Neurosurgery trainees from international programs located in Ankara, Turkey; San Salvador, El Salvador; and Moshi, Tanzania, interacted with and assessed the 3D models and AR cube system and then completed a 17-item graded user experience survey.

RESULTS Seven photogrammetry 3D models were created and imported to the cube. Horizontal turntable rotation of the cube translated to measurable and realistic perspective changes in the surgical window area. The combined 3D models and cube system were used to engage trainees during cadaveric dissections, with satisfactory user experience. Thirty-five individuals (20 from Turkey, 10 from El Salvador, and 5 from Tanzania) agreed that the cube system could enhance the learning experience for neurosurgical anatomy.

CONCLUSIONS The AR cube combines tactile and visual sensations with high-resolution 3D models of cadaveric dissections. Inexpensive and lightweight, the cube can be effectively implemented to allow independent co-visualization of anatomical dissection and can potentially supplement neurosurgical education.

Posted on

Novel Use of Bilateral Prone Transpsoas Approach for the Treatment of Transforaminal Interbody Fusion Pseudarthrosis and Interbody Cage Subsidence

Operative Neurosurgery 27:86–93, 2024

Pseudarthrosis is a complication after transforaminal lumbar interbody fusion (TLIF) that leads to recurrent symptoms and potential revision surgery. Subsidence of the interbody adds to the complexity of surgical revision. In addition, we report a novel technique for the treatment of TLIF pseudarthrosis with subsidence and propose an approach algorithm for TLIF cage removal.

METHODS: Cases of reoperation for TLIF pseudarthrosis were reviewed. We report a novel technique using a bilateral prone transpsoas (PTP) approach to remove a subsided TLIF cage and place a new lateral cage. An approach algorithm was developed based on the experience of TLIF cage removal. The patient was placed in the prone position with somatosensory evoked potential and electromyography monitoring. A PTP retractor was placed using standard techniques on the ipsilateral side of the previous TLIF. After the discectomy, the subsided TLIF cage was visualized but unable to be removed. The initial dilator was closed, and a second PTP retractor was placed on the contralateral side. After annulotomy and discectomy to circumferentially isolate the subsided cage, a box cutter was used to push and mobilize the TLIF cage from this contralateral side, which could then be pulled out from the ipsilateral side. A standard lateral interbody cage was then placed.

RESULTS: Retractor time was less than 10 minutes on each side. The patient’s symptoms resolved postoperatively. We review illustrative cases of various approaches for TLIF cage removal spanning the lumbosacral spine and recommend an operative approach based on the lumbar level, degree of subsidence, and mobility of the interbody.

CONCLUSION: Bilateral PTP retractors for TLIF cage removal may be effectively used in cases of pseudarthrosis with severe cage subsidence. Careful consideration of various factors, including patient surgical history, body habitus, and intraoperative findings, is essential in determining the appropriate treatment for these complex cases.

Posted on

Presentation and Management of Cerebral Venous Sinus Thrombosis After Supratentorial Craniotomy

Neurosurgery 95:34–45, 2024

Cerebral venous sinus thrombosis (CVST) after supratentorial craniotomy is a poorly studied complication, for which there are no management guidelines. This study assessed the incidence, associated risk factors, and management of postoperative CVST after awake craniotomy.

METHODS: This is an observational, retrospective, monocentric analysis of patients who underwent a supratentorial awake craniotomy. Postoperative CVST was defined as a flow defect on the postoperative contrast-enhanced 3D T1weighted sequence and/or as a T2* hypointensity within the sinus.

RESULTS: In 401 supratentorial awake craniotomies (87.3% of diffuse glioma), the incidence of postoperative CVST was 4.0% (95% CI 2.5-6.4): 14/16 thromboses located in the superior sagittal sinus and 12/16 located in the transverse sinus. A venous sinus was exposed during craniotomy in 45.4% of cases, and no intraoperative injury to a cerebral venous sinus was reported. All thromboses were asymptomatic, and only two cases were diagnosed at the time of the first postoperative imaging (0.5%). Postoperative complications, early postoperative Karnofsky Performance Status score, and duration of hospital stay did not significantly differ between patients with and without postoperative CVST. Adjusted independent risk factors of postoperative CVST were female sex (adjusted Odds Ratio 4.00, 95% CI 1.24-12.91, P = .021) and a lesion ≤1 cm to a venous sinus (adjusted Odds Ratio 10.58, 95% CI 2.93-38.20, P < .001). All patients received standard prophylactic-dose anticoagulant therapy, and none received treatment-dose anticoagulant therapy. No thrombosis-related adverse event was reported. All thromboses presented spontaneous sinus recanalization radiologically at a mean of 89 ± 41 days (range, 7-171).

CONCLUSION: CVST after supratentorial awake craniotomy is a rare event with satisfactory clinical outcomes and spontaneous sinus recanalization under conservative management without treatment-dose anticoagulant therapy. These findings are comforting to neurosurgeons confronted with postoperative MRI reports suggesting CVST.

Posted on

Transarterial Embolization of Dural Arteriovenous Fistulas: Conventional, Pressure Cooker, and Microballoon Catheter Embolization Techniques

Operative Neurosurgery 27:65–71, 2024

Dural fistulas are abnormal connections between dural arteries and intracranial veins treated mainly endovascularly in most settings. The aim was to examine a single-institution experience of microballoon catheter transarterial embolization (TAE) of dural arteriovenous fistulas (dAVFs) and compare it with other TAE techniques.

METHODS: We retrospectively identified all dAVFs treated at our institution between 2017 and 2022 with microballoon, conventional, and pressure cooker TAE. We studied occlusion and retreatment rates, treatment-related complications, and radiation doses.

RESULTS: During the study period, 66 patients underwent 75 TAE procedures to treat 68 dAVFs: 47 conventional TAE, 14 pressure cooker TAE, and 14 microballoon TAE. Median age of the study population was 63 years with 32% females. The most common dAVF location was the transverse sinus and 20% of dAVFs presented with hemorrhage. At 3-month follow-up, stable complete occlusion of the dAVF was seen in 72% (n = 34) after conventional TAE, 79% (n = 11) after pressure cooker TAE, and 86% (n = 12) after microballoon TAE. Retreatment was required in 19% (n = 9) after conventional TAE, 7% (n = 1) after pressure cooker TAE, and 7% (n = 1) after microballoon TAE. Treatment-related complications occurred in 17% (n =) after conventional TAE, 29% (n = 4) after pressure cooker TAE, and 7% (n = 1) after microballoon TAE.

CONCLUSION: In our experience, microballoon TAE of dAVFs resulted in better initial and 3-month angiographic outcomes and required less retreatment than conventional TAE. Microballoon TAE also resulted in fewer treatmentrelated complications than other techniques. In our experience, microballoon TAE is a reliable and safe endovascular technique to treat dAVFs.

Posted on

Efficacy and Safety of Carmustine Wafer Implantation After Ventricular Opening in Glioblastomas, Isocitrate Dehydrogenase-Wildtype, in Adults

Neurosurgery 94:1227–1236, 2024

We assessed the impact of ventricular opening on postoperative complications and survival of carmustine wafer implantation during surgery of newly diagnosed supratentorial glioblastomas, isocitrate dehydrogenase (IDH)-wildtype in adults.

METHODS: We performed an observational, retrospective, single-center cohort study at a tertiary surgical neurooncological center between January 2006 and December 2021.

RESULTS: One hundred ninety-four patients who benefited from a first-line surgical resection with carmustine wafer implantation were included. Seventy patients (36.1%) had a ventricular opening. We showed that ventricular opening (1) did not increase overall postoperative complication rates (P = .201); (2) did not worsen the early postoperative Karnofsky Performance Status score (P = .068); (3) did not increase the time interval from surgery to adjuvant oncological treatment (P = .458); (4) did not affect the completion of the standard radiochemotherapy protocol (P = .164); (5) did not affect progression-free survival (P = .059); and (6) did not affect overall survival (P = .142).

CONCLUSION: In this study, ventricular opening during first-line surgical resection did not affect the survival and postoperative complications after use of carmustine wafer implantation in adult patients with a newly diagnosed supratentorial glioblastoma, IDH-wildtype. This warrants a prospective and multicentric study to clearly assess the impact of the ventricular opening after carmustine wafer implantation in glioblastoma, IDH-wildtype.

Posted on

A Retrospective Cohort Study Evaluating the Comparative Effectiveness of Unilateral Hemilaminectomy and Bilateral Laminectomy in the Resection of Spinal Meningiomas

Operative Neurosurgery 26:685–694, 2024

The primary treatment modality for spinal meningiomas (SM) is surgical resection. In recent years, minimal invasive spine surgery has gained considerable popularity, attributing its growth to advancements in surgical technologies and improved training of surgeons. Nonetheless, the suitability and effectiveness of minimal invasive spine surgery for intradural spinal tumor resection remain a subject of debate. In this cohort study, we aimed to compare the extent of resection of the unilateral hemilaminectomy approach, a less invasive technique, with the more traditional and invasive bilateral laminectomy.

METHODS: We performed a retrospective cohort study including patients with SM who underwent surgery at our department between 1996 and 2020. Cohorts included patients who underwent tumor resection through bilateral laminectomy and patients who underwent a unilateral hemilaminectomy. The primary end point was extent of resection according to the Simpson classification.

RESULTS: Of 131 with SM, 36 had a bilateral laminectomy and 95 were operated through a unilateral hemilaminectomy. In both groups, gross total resection, Simpson grades 1 and 2, was achieved in 94.44% and 94.74%, respectively (P = .999). The neurological outcome was also comparable in both cohorts (P = .356). Both length of hospital stay and estimated blood loss were significantly lower in the unilateral cohort (P < .05).

CONCLUSION: The results of this study indicate that the unilateral hemilaminectomy yields comparable results in both oncological and neurological outcome when compared with the bilateral laminectomy. Thus, unilateral hemilaminectomy may serve as a viable and safe alternative for the surgical removal of SM.

Posted on

Reversal of Middle Cerebral Artery Stenosis by Minimally Invasive Intracerebral Hematoma Evacuation

Neurosurgery Practice 2024;5(2):e00087.

Acute intracerebral hematomas are known to induce significant mass effects within the brain, leading to critical complications such as cerebral midline shift, herniation, and increased intracranial pressure. The timing and efficacy of intracerebral hematoma evacuation remain subjects of ongoing debate in current literature.

CLINICAL PRESENTATION: In our case report, we present a 74-year-old female patient diagnosed with basal ganglia hematoma. The resultant mass effect from the intracerebral hematoma led to middle cerebral artery (MCA) stenosis. Notably, early-stage minimally invasive hematoma evacuation was pivotal in facilitating successful revascularization of the MCA.

CONCLUSION: Our case underscores the significance of prompt identification and management of MCA stenosis arising from intracerebral hematoma. Early intervention through minimally invasive hematoma evacuation proved instrumental in achieving successful MCA revascularization. These findings emphasize the critical role of timely interventions in mitigating potential complications associated with intracerebral hematoma.

Posted on

Percutaneous thermal radiofrequency rhizotomy of L2–S1 spinal nerve roots in children with cerebral palsy

Neurosurg Focus 56(6):E7, 2024

This study presents the results of an evaluation of the effectiveness of percutaneous thermal radiofrequency (RF) ablation of spinal nerve roots to reduce spasticity and improve motor function in children with cerebral palsy (CP).

METHODS A retrospective analysis was conducted on the surgical treatment outcomes of 26 pediatric patients with severe CP (Gross Motor Function Classification System levels IV–V). The assessment protocol included muscle tone assessment using the modified Ashworth scale (MAS), evaluation of passive and active range of motion, gait video recording, and locomotor status evaluation using the Gross Motor Function Measure (GMFM)–88 scale. Thermal RF rhizotomy (ablation of spinal nerve roots) was performed on all patients at the L2–S1 levels at 70°C for 90 seconds. The statistical data analysis was conducted using the t-test and Mann-Whitney U-test. A p value < 0.05 was considered statistically significant.

RESULTS Before the operation, the average level of spasticity in the lower-limb muscles of all patients was 3.0 ± 0.2 according to the MAS. In the early postoperative period, the spasticity level in all examined muscle groups significantly decreased to a mean of 1.14 ± 0.15 (p < 0.001). In the long-term postoperative period, the spasticity level in the examined muscle groups averaged 1.49 ± 0.17 points on the MAS (p < 0.001 compared to baseline, p = 0.0416 compared to the early postoperative period). Despite the marked reduction of spasticity in the lower limbs, no significant change in locomotor status according to the GMFM-88 scale was observed in the selected category of patients. In the long-term period, during the control examination of patients, the GMFM-88 level increased on average by 3.6% ± 1.4% (from 22.2% ± 3.1% to 25.8% ± 3.6%).

CONCLUSIONS The findings of this study offer preliminary yet compelling evidence that RF ablation of spinal nerve roots can lead to a significant and enduring decrease in muscle tone among children with severe spastic CP. Further studies and longer-term data of the impact on functionality and quality of life of patients with CP after spinal root RF ablation are needed.

Proudly powered by WordPress