Retrosigmoid Transtentorial Approach Compared to Traditional Transpetrosal Approaches for the Resection of Petroclival Meningiomas: A Case-Control Study.

Background Transpetrosal approaches have become standard technique for resection of petroclival meningiomas (PCM). The retrosigmoid craniotomy has also been extensively studied as an alternative approach. The need to resect the tentorium at the end of a retrosigmoid approach has been described, but the upfront transtentorial variation of the retrosigmoid craniotomy has never been described nor evaluated in detail as a possible alternative to the standard petrosectomy approaches. Objective This study was aimed to directly compare the transpetrosal approaches to the retrosigmoid transtentorial approach (RSTTA) in terms of degree of resection, duration of surgery, and estimated blood loss (EBL). Methods A retrospective case-control study of patients who underwent resection of PCM between January 2014 and December 2018 was performed. Patients in the two surgical approach groups were matched for age and tumor location. The primary measured outcomes were duration of surgery, EBL, extent of resection, length of postoperative hospital stay, and complications. Data analysis was performed using analysis of variance (ANOVA), multivariate analysis of variance (MANOVA), and analysis of covariance (ANCOVA) tests. Results Thirteen patients had microsurgical resection of PCM at our center between January 2014 and December 2018. Nine patients underwent a transpetrosal approach and four patients underwent RSTTA. The average duration of surgery was shorter in the RSTTA group (425 vs. 525.4 minutes) and had less blood loss (94 vs. 425 mL). Extent of resection was comparable between the groups. Conclusion The RSTTA appears to be a safe and efficient technique for resecting PCMs and in selected cases a valid alternative to standard petrosectomies approaches.

Skull Base Training and Mentorship.

OBJECTIVE: To review teaching and mentoring techniques of experienced skull base surgeons and educators STUDY DESIGN:: Expert commentary. SETTING: 8th Quadrennial International Conference on vestibular schwannoma and other CPA tumors, panel on teaching, and mentoring. MAIN OUTCOME MEASURES: Experiences and opinions of experienced skull base surgeons, both neurosurgeons and neurotologists, presented and discussed at the conference. CONCLUSIONS: Obtaining surgical mastery is essential for the teachers of skull base surgery. Hard work and practice with immediate and constant feedback on performance is an essential component to success. Creating a patient-centered culture that encourages academic achievement is an accelerator for success of a training program. Both the mentor and the mentee must play an intentional and active role to maximize learning.

Human Bone Marrow Endothelial Progenitor Cell Transplantation into Symptomatic ALS Mice Delays Disease Progression and Increases Motor Neuron Survival by Repairing Blood-Spinal Cord Barrier.

Convincing evidence demonstrated impairment of the blood-spinal cord barrier (BSCB) in Amyotrophic Lateral Sclerosis (ALS), mainly by endothelial cell (EC) alterations. Replacing damaged ECs by cell transplantation is a potential barrier repair strategy. Recently, we showed that intravenous (iv) administration of human bone marrow CD34+ (hBM34+) cells into symptomatic ALS mice benefits BSCB restoration and postpones disease progression. However, delayed effect on motor function and some severely damaged capillaries were noted. We hypothesized that hematopoietic cells from a restricted lineage would be more effective. This study aimed to establish the effects of human bone marrow-derived endothelial progenitor cells (hBMEPCs) systemically transplanted into G93A mice at symptomatic disease stage. Results showed that transplanted hBMEPCs significantly improved behavioral disease outcomes, engrafted widely into capillaries of the gray/white matter spinal cord and brain motor cortex/brainstem, substantially restored capillary ultrastructure, significantly decreased EB extravasation into spinal cord parenchyma, meaningfully re-established perivascular astrocyte end-feet, and enhanced spinal cord motor neuron survival. These results provide novel evidence that transplantation of hBMEPCs effectively repairs the BSCB, potentially preventing entry of detrimental peripheral factors, including immune/inflammatory cells, which contribute to motor neuron dysfunction. Transplanting EC progenitor cells may be a promising strategy for barrier repair therapy in this disease.

Successful Microvascular Decompression For Trigeminal Neuralgia Secondary to a Persistent Trigeminal Artery.

BACKGROUND AND IMPORTANCE: Persistent trigeminal artery (PTA) is a rare but important anatomic variant that contributes to trigeminal neuralgia (TN). Microvascular decompression (MVD) of the responsible vessel(s) away from the trigeminal nerve provides the most complete and durable relief from TN. The role and technique of MVD for TN associated with a PTA has not been fully defined in the literature. Furthermore, assessment of PTA anatomy intraoperatively with a microscope is challenging. We report the first 3-dimensional (3D) microscopic video and first intraoperative endoscopic video of a successful MVD of the trigeminal nerve in a patient who suffered TN from a tortuous, compressive PTA. CLINICAL PRESENTATION: A 66-yr-old right-handed female presented with right facial pain in V2 and V3 distributions with a clinical picture of TN. Imaging demonstrated trigeminal nerve compression secondary to a PTA and MVD was performed with a 3D operative microscope and an endoscope. The PTA appeared to compress the nerve directly at the trigeminal porus and also had compressive superior cerebellar artery variant branches. The nerve was decompressed at all points of compression with Teflon pledgets along its entire cisternal length. Postoperatively, she is free with trigeminal pain episodes at 4-mo follow-up. CONCLUSION: In cases of TN associated with a PTA, we recommend decompression along the entire length of the nerve wherever there is compression. Furthermore, we find both the operative microscope and particularly the endoscope useful to assess vascular anatomy intraoperatively.

A Pivotal Randomized Clinical Trial Evaluating the Safety and Effectiveness of a Novel Hydrogel Dural Sealant as an Adjunct to Dural Repair.

BACKGROUND: A watertight dural repair is critical to minimizing the risk of postoperative complications secondary to cerebrospinal fluid (CSF) leaks. OBJECTIVE: To evaluate the safety and efficacy of a novel hydrogel, Adherus Dural Sealant, when compared with control, DuraSeal Dural Sealant System, as an adjunct to standard methods of dural repair. METHODS: In this 17-center, prospective, randomized clinical trial designed as a noninferiority, single-blinded study, 124 patients received Adherus Dural Sealant (test sealant) and 126 received DuraSeal (control). The primary composite endpoint was the proportion of patients who were free of any intraoperative CSF leakage during Valsalva maneuver after dural repair, CSF leak/pseudomeningocele, and unplanned retreatment of the surgical site. Each component was then analyzed individually as a secondary endpoint. Patients were followed for 4 mo after surgery. RESULTS: The primary composite endpoint at the 120-d follow-up was achieved in 91.2% of the test sealant group compared with 90.6% of the control, thus showing that the test sealant was statistically significantly noninferior to DuraSeal ( P = .0049). Post hoc analysis of the primary composite endpoint at 14 d demonstrated superiority of the test sealant over the control ( P = .030). Primary endpoint failures in the control group tended to occur early in follow-up period, while a majority of test dural sealant failures were identified through protocol-required radiographic imaging at the 120-d follow-up visit. CONCLUSION: The test sealant, Adherus Dural Sealant, is a practical, safe, and effective adjunct to achieving a watertight dural closure after primary dural closure in cranial procedures.

Denervation of the Eustachian Tube and Hearing Loss Following Trigeminal Schwannoma Resection.

Objectives To discuss eustachian tube dysfunction (ETD) as a cause of hearing loss and to discuss its pathogenesis following resection of trigeminal schwannomas. Methods Presented herein are two cases of trigeminal schwannoma that were resected surgically with sacrifice of the motor branch of the trigeminal nerve. Neither of the cases had evidence of extracranial extension nor preoperative ETD. Both patients developed ETD and have been followed without evidence of schwannoma recurrence. Conclusions Trigeminal schwannomas are rare tumors that typically require surgical resection. Hearing loss is a potential postsurgical deficit and warrants evaluation by an otolaryngologist with consideration given to a preoperative audiogram. ETD as a result of trigeminal motor branch sacrifice should be included in the differential diagnosis of postoperative hearing loss in this patient subset as it may be reversed with placement of a tympanostomy tube.

C-shaped Incision for Far-Lateral Suboccipital Approach: Anatomical Study and Clinical Correlation.

Background The standard incision for far-lateral suboccipital approaches has been the classic "reverse hockey stick." Although that incision provides ample exposure, concern has been raised that excessive muscle dissection and skin elevation might lead to accumulation of cerebrospinal fluid (CSF) under the flap with increased risk of CSF leak. We hypothesize that the C-shaped incision can minimize the amount of muscle dissection and provide optimal exposure and surgical outcomes. Objective To describe the anatomical dissection for the C-shaped incision and clinical application of the C-shaped incision for the far-lateral approach. Methods A retrospective analysis of all the patients operated on at our center using this approach for the treatment of aneurysm of the posterior inferior cerebellar artery (PICA) from 2005 to 2011. Results of clinical and operative outcome are evaluated. Surgical techniques are described in detail. Cadaveric dissections using the C-shaped incision were performed to assess the exposure of the far-lateral suboccipital area. Results Eleven consecutive patients who had undergone this procedure were selected. All patients underwent clipping of PICA aneurysms. Nine patients (82%) presented with ruptured aneurysms and subarachnoid hemorrhage. All of them underwent suboccipital craniectomy and C1 laminectomy. The dura mater was closed in a watertight fashion in 10 patients (91%). No CSF leak or pseudomeningocele were reported. In nine SAH patients, two (22%) had postoperative dysphagia and required long-term percutaneous endoscopic gastrostomy tube placement. One patient (11%) had chronic respiratory failure and required a tracheostomy. Three patients (33%) developed hydrocephalus and required a ventriculoperitoneal shunt. Conclusions The C-shaped incision is a valid alternative to the classic reverse hockey-stick incision to gain exposure for far-lateral craniotomies. Knowing the anatomy and dissection techniques can provide an easy and safe route to address anterior lateral cranial-cervical lesions. Our results suggest the C-shaped incision is reliable in preventing CSF leak and the formation of pseudomeningocele.

Anterior inferior petrosectomy: defining the role of endonasal endoscopic techniques for petrous apex approaches.

OBJECT: Historically, surgery to the petrous apex has been addressed via craniotomy and open microscopic anterior petrosectomy (OAP). However, with the popularization of endoscopic approaches, the petrous apex can further be approached endonasally by way of an endoscopic endonasal anterior petrosectomy (EAP). Endonasal anterior petrosectomy is a relatively new procedure and has not been compared anatomically with OAP. The authors hypothesized that the EAP and OAP techniques approach different portions of the petrous apex and therefore may have different applications. METHODS: Four cadaveric heads were used. An OAP was performed on one side and an EAP was performed on the contralateral side; the limits of bony resection were defined. The extent of bony resection was then evaluated using predissection and postdissection thin-slice CT scans. The comparative resection was then reconstructed using 3D modeling on Brainlab workstations. RESULTS: The average resection volumes for EAP and OAP were 0.297 cm(3) and 0.649 cm(3), respectively, representing a comparative percentage of 46% (EAP/OAP). An EAP and OAP achieved resection of 29% and 64% of the total petrous apex volume, respectively. Indeed, EAP addressed the inferior portion of the petrous apex located adjacent to the petroclival suture more completely than OAP, where 45% of the bone overlying the petroclival suture (petroclival angle to the jugular foramen) was resected with the EAP, while 0% was resected with the OAP. CONCLUSIONS: In anatomically normal cadavers, OAP achieved nearly a 50% larger volumetric resection than EAP. Furthermore, while OAP appears to completely address the superior portion of the petrous apex, EAP appears to have a niche in approaches to lesions in the inferior petrous apex. Given these results, the authors propose that OAP be redefined as the "superior anterior petrosectomy," while EAP be referred to as the "inferior anterior petrosectomy," which more clearly defines the role of each approach in anterior petrosectomy.

Field of view comparison between two-dimensional and three-dimensional endoscopy.

OBJECTIVES/HYPOTHESIS: Relative to microscopic transnasal surgery, endoscopic surgery provides improved visualization with an increased field of view. Advances such as high-definition (HD) and three-dimensional (3D) endoscopy have been introduced and clearly improve visualization. However, do both technologies maintain an increased field of view? We hypothesize that the field of view of 3D endoscopy is restricted relative to two-dimensional (2D) HD endoscopy. STUDY DESIGN: Laboratory investigation, prospective case series. METHODS: Standard measurements at 6-cm and 2-cm working distances where made to determine the comparative field of view utilizing Storz 0° 2D HD and Visionsense 3D endoscopes. Relative measurements were then made to determine field of view. Five clinical patients were then utilized to confirm laboratory studies and demonstrate the relative field of view change. RESULTS: 3D endoscopy demonstrates a 52% loss of field of view compared to 2D endoscopy in a controlled lab testing. This was confirmed in a small clinical patient series where a 55% ± 3% relative field of view reduction was observed. CONCLUSIONS: When working with 3D endoscopy in a currently available commercial product, the operator should be aware that relative to HD 2D endoscopy, there is a field of view restriction of 52%. LEVEL OF EVIDENCE: N/A.

Epidemiological survey-based formulae to approximate incidence and prevalence of neurological disorders in the United States: a meta-analysis.

BACKGROUND: This study aims to create a convenient reference for both clinicians and researchers so that vis-à-vis comparisons between brain disorders can be made quickly and accurately. We report here the incidence and prevalence of the major adult-onset brain disorders in the United States using a meta-analysis approach. MATERIAL AND METHODS: Epidemiological figures were collected from the most recent, reliable data available in the research literature. Population statistics were based on the most recent census from the US Census Bureau. Extrapolations were made only when necessary. The most current epidemiological studies for each disorder were chosen. All effort was made to use studies based on national cohorts. Studies reviewed were conducted between 1950 and 2009. The data of the leading studies for several neurological studies was compiled in order to obtain the most accurate extrapolations. Results were compared to commonly accepted values in order to evaluate validity. RESULTS: It was found that 6.75% of the American adult population is afflicted with brain disorders. This number was eclipsed by the 8.02% of Floridians with brain disorders, which is due to the large aged population residing in the state. CONCLUSIONS: There was a noticeable lack of epidemiological data concerning adult-onset brain disorders. Since approximately 1 out of every 7 households is affected by brain disorders, increased research into this arena is warranted.

Acoustic neuroma observation associated with an increase in symptomatic tinnitus: results of the 2007-2008 Acoustic Neuroma Association survey.

OBJECT: Tinnitus is a known presenting symptom of acoustic neuromas, but little is known about the impact of observation or treatment on tinnitus. Most patients experience improvement with treatment, while others may worsen. Therefore, this study was designed to assess the overall impact of observation and treatment on tinnitus outcome in patients with acoustic tumors. METHODS: Data from the 2007-2008 Acoustic Neuroma Association survey were used. Tinnitus severity was graded both at presentation and at last follow-up for all patients questioned. This data set was analyzed using the Student t-test and a linear regression model adjusted for possible confounders. RESULTS: Overall there were more patients receiving intervention (n = 1138) for their acoustic neuromas than observation (n = 289). Presenting tumor size positively correlated with tinnitus severity score. Regardless of treatment (microsurgery or stereotactic radiosurgery), tinnitus improved at last follow-up and worsened in those who were observed (p = 0.02). When comparing microsurgical options, retrosigmoid and translabyrinthine resection improved tinnitus symptoms (both p < 0.01). Stereotactic radiosurgery had a treatment effect similar to microsurgery. CONCLUSIONS: Presenting tinnitus severity correlates strongly with tumor size. Furthermore, regardless of treatment, there appears to be an overall reduction in tinnitus severity for all forms of microsurgery and stereotactic radiosurgery. Importantly, observation leads to a worsening in symptomatic tinnitus and therefore should be weighed in the treatment recommendation.

Catheter fixation and ligation: a simple technique for ventriculostomy management following endovascular stenting.

The object of this study was to describe a unique method of managing ventriculostomy catheters in patients on antithrombotic therapy following endovascular treatment of ruptured intracranial aneurysms. The authors retrospectively reviewed 3 cases in which a unique method of ventriculostomy management was used to successfully avoid catheter-related hemorrhage while the patient was on dual antiplatelet therapy. In this setting, ventriculostomy catheters are left in place and fixed to the calvarium with titanium straps effectively ligating them. The catheter is divided and the distal end is removed. The proximal end can be directly connected to a distal shunt system during this stage or at a later date if necessary. The method described in this report provided a variety of management options for patients requiring external ventricular drainage for subarachnoid hemorrhage. No patient suffered catheter-related hemorrhage. This preliminary report demonstrates a safe and effective method for discontinuing external ventricular drainage and/or placing a ventriculoperitoneal shunt in the setting of active coagulopathy or antithrombotic therapy. The technique avoids both the risk of hemorrhage related to catheter removal and reinsertion and the thromboembolic risks associated with the reversal of antithrombotic therapy. Some aneurysm centers have avoided the use of stent-assisted coiling in cases of ruptured aneurysms to circumvent ventriculostomy-related complications; however, the method described herein should allow continued use of this important treatment option in ruptured aneurysm cases. Further investigation in a larger cohort with long-term follow-up is necessary to define the associated risks of infection using this method.

Paradoxical trends in the management of vestibular schwannoma in the United States.

OBJECT: Recent natural history studies of vestibular schwannomas (VSs) suggest that most of these tumors do not grow. The impact of these new data on management trends in the US is currently unknown. The aim in the present study was to evaluate current trends in the treatment of VS in the US by analyzing a national cancer database. METHODS: The Surveillance, Epidemiology, and End Results Program is a national database maintained by the National Cancer Institute representing 26% of the US population. Data from the database were downloaded using provided software. Cases were isolated based on histology codes and the site code. Data from 2004 to 2007 were included in the analysis. The number of patients undergoing resection was compared with the number treated with beam radiation and observation, based on tumor size. RESULTS: Three thousand six hundred fifty cases were identified in the database. Over the study period, management choices for VSs showed a significant change only for tumors with a diameter < 2 cm. In this tumor category, a decrease in resection and an increase in radiation were observed, with observation showing a modest increase but remaining low at an average of 25%. CONCLUSIONS: Study data demonstrated a shift in the management of small VSs in the US between 2004 and 2007, with microsurgical removal giving way to radiation treatment and the overall rate for observation remaining low and stable. With recent literature suggesting that the majority of small tumors do not grow, the authors assert that VSs are being overtreated in the US.

A multicenter, single-blind, prospective randomized trial to evaluate the safety of a polyethylene glycol hydrogel (Duraseal Dural Sealant System) as a dural sealant in cranial surgery.

OBJECTIVE: Incisional cerebrospinal fluid (CSF) leakage after cranial surgery is a significant cause of morbidity due to poor wound healing and infection, meningitis, and pseudomeningocele formation. Many common dural closure techniques, such as sutures, autologous grafts, gelatin or collagen sponges, and fibrin glues, are used to achieve watertight closure, although none are US Food and Drug Administration approved for this use. DuraSeal Dural Sealant System is a polyethylene glycol (PEG) hydrogel approved by the U.S. Food and Drug Administration for obtaining watertight dural closure when applied after standard dural suturing. This multicenter, prospective randomized study further evaluated the safety of a PEG hydrogel compared with common dural sealing techniques. METHODS: A total of 237 patients undergoing elective cranial surgery at 17 institutions were randomized to dural closure augmented with the PEG hydrogel or a control "standard of care" dural sealing technique after Valsalva maneuver demonstrated an intraoperative nonwatertight dural closure. Data were collected on complications resulting in unplanned postoperative interventions or reoperations, surgical site infections, CSF leaks, and other neurological complications within 30 days. Surgeons also provided data on the ease of use of the dural sealing techniques, as well as preparation and application times. RESULTS: The incidences of neurosurgical complications, surgical site infections, and CSF leaks were similar between treatment and control groups, with no statistically significant difference between the measures. In the PEG hydrogel group (n = 120), the incidence of neurosurgical complications was 5.8% (n = 7), the incidence of surgical site infections was 1.7% (n = 2), and the incidence of CSF leak was 0.8% (n = 1). In the control group (n = 117), the incidence of neurosurgical complications was 7.7% (n = 9), the incidence of surgical site infection was 2.6% (n = 3), and the incidence of CSF leak was 1.7% (n = 2). Sealant preparation time was less than 5 minutes in 96.6% of the PEG hydrogel group compared with 66.4% of controls (P < 0.001). The dural augmentation was applied in less than 1 minute in 85.7% of the PEG hydrogel group compared with 66.4% of the control group (P < 0.001). CONCLUSIONS: The PEG hydrogel dural sealant used in this study has a similar safety profile to commonly used dural sealing techniques when used as dural closure augmentation in cranial surgery. The PEG hydrogel dural sealant demonstrated faster preparation and application times than other commonly used dural sealing techniques.

Combined subgaleal/myocutaneous technique for temporalis muscle dissection.

Background The frontal branch of the facial nerve (FBFN) is the most susceptible neural structure to injury during frontotemporal craniotomies. The balance between adequate temporalis muscle mobilization and frontal branch protection with minimal anatomical alteration is the philosophy behind our approach to temporalis muscle dissection. Objective To describe a combined subgaleal/myocutaneous technique for dissection and mobilization of the temporalis muscle in anterolateral cranial approaches. Methods Interdisciplinary literature review of the anatomical course of the FBFN was performed. Retrospective analysis of anterolateral craniotomies performed at our institution in which the combined subgaleal/myocutaneous (CSGMC) technique was performed. Results A total of 71 cases of anterolateral craniotomies (excluding full variant orbitozygomatic) were performed with the successful application of a CSGMC technique (36 pterional, 31 orbitopterional, and 4 fronto-orbital). Partial frontalis weakness was transient in one case. Conclusion The CSGMC technique provides sufficient protection for the FBFN and allows for adequate mobilization for a variety of skull base exposures while minimally violating myofascial anatomy. This is the first reported technique that allows both adequate temporalis muscle mobilization with performance of the one-piece orbitofrontal and orbitopterional approaches, without disruption of the superficial/deep temporalis fascia and fat-pad complex.

Paradoxical trends in the management of unruptured cerebral aneurysms in the United States: analysis of nationwide database over a 10-year period.

BACKGROUND AND PURPOSE: The objective of this study was to characterize demographics, treatments, and outcomes in the management of unruptured cerebral aneurysms in the United States using a national healthcare database. METHODS: Clinical data were derived from the Nationwide Inpatient Sample for the years 1997 through 2006. Patients with unruptured cerebral aneurysms were identified using the appropriate International Classification of Diseases, 9th Revision code (437.3). Hospitalizations, length of stay, hospital charges, discharge pattern, age and gender distribution, and nature of intervention were analyzed. A Bureau of Labor statistics tool was used to adjust hospital and national charges for inflation. Population-adjusted rates were calculated using population estimates generated by the U.S. Census Bureau. RESULTS: Over 100 000 records were retrieved for analysis. During the time period studied, there was a 75% increase in the number of hospitalizations associated with unruptured cerebral aneurysms. Inflation adjusted hospital charges increased by 60%, whereas the total national bill increased by 200%. Overall, length of stay decreased by 37% and in-hospital mortality rates decreased by 54%. The increasing number of hospitalizations and total national charges related to inpatient treatment of unruptured aneurysms were significantly associated with endovascular treatment rather than surgical clipping. CONCLUSIONS: Despite recent studies suggesting a low risk of rupture of incidentally diagnosed cerebral aneurysms, data from this study suggest an increasing trend of treatment for this entity in the United States. Furthermore, endovascular intervention is now the major driving force behind the increasing overall national charges. Given the current healthcare climate, the impact of these trends warrants discussion and debate.

Life without the vein of Galen: Clinical and radiographic sequelae.

A thorough understanding of the anatomy of the pineal region, particularly venous drainage, is critical for gaining open surgical access to the pineal gland. The adverse sequelae after intraoperative venous occlusion are assumed to be catastrophic but have been scarcely reported. We report a case of pineocytoma in which the vein of Galen was ligated without postoperative adverse sequelae. Pineal region anatomy with emphasis on deep veins was reviewed in large anatomical studies. There are tremendous anatomical variations in the vein of Galen and its tributaries. Several confounding factors can be encountered during surgery and may lead to accidental sacrifice of the vein of Galen. Survival after focal occlusion of a major deep vein depends on the development of collateral circulation as shown in our case report. Venous drainage remains the cornerstone in the surgical planning of the pineal region. Anatomical variations and venous collaterals undoubtedly contributed to the mixed reports of adverse sequelae after venous sacrifice. Vein of Galen ligation may be survivable but consequences cannot be predicted without a thorough pre-ligation assessment of regional venous collateral drainage. Thorough understanding of the venous anatomy, meticulous planning of the surgical approach and avoidance of the occlusion of the vein of Galen and its major tributaries are key factors to successful pineal region surgery.

Management of the great mimicker: Meckel cave tumors.

BACKGROUND: Meckel cave tumors are often asymptomatic and have a sufficiently characteristic magnetic resonance imaging/computed tomography signature that allows treatment/surveillance decisions to be made without biopsy confirmation. Radiographic diagnosis requires the surgeon to be fully aware of the plethora of unusual Meckel cave lesions that mimic benign tumors when they are malignant, inflammatory, or infectious and in need of a completely different and often timely intervention. When such a diagnosis is considered, it behooves the surgeon and benefits the patient to have a percutaneous biopsy technique available. OBJECTIVE: To use our recent experience with a patient with idiopathic inflammatory sensory neuropathy and another with Meckel cave lymphoma to review the management of tumors of the Meckel cave. METHODS: The technique of percutaneous biopsy of Meckel cave tumors through the foramen ovale with biopsy needles is detailed. CONCLUSION: Obtaining tissue biopsy percutaneously prevents patients with Meckel cave tumors best treated with nonsurgical management from undergoing open surgical resection with its concomitant morbidity.