Publications by authors named "Moncef Berhouma"

48 Publications

Management, functional outcomes and survival in a French multicentric series of 118 adult patients with cerebellar glioblastoma.

J Cancer Res Clin Oncol 2021 Jan 5. Epub 2021 Jan 5.

Department of Neurosurgery, Hospices Civils de Lyon, Hôpital Neurologique Pierre Wertheimer, 59 Boulevard Pinel, 69667, Bron, France.

Purpose: To analyze the outcomes and predictors in a large series of cerebellar glioblastomas in order to guide patient management.

Methods: The French brain tumor database and the Club de Neuro-Oncologie of the Société Française de Neurochirurgie retrospectively identified adult patients with cerebellar glioblastoma diagnosed between 2003 and 2017. Diagnosis was confirmed by a centralized neuropathological review.

Results: Data from 118 cerebellar glioblastoma patients were analyzed (mean age 55.9 years, 55.1% males). The clinical presentation associated raised intracranial pressure (50.8%), static cerebellar syndrome (68.6%), kinetic cerebellar syndrome (49.2%) and/or cranial nerve disorders (17.8%). Glioblastomas were hemispheric (55.9%), vermian (14.4%) or both (29.7%). Hydrocephalus was present in 49 patients (41.5%). Histologically, tumors corresponded either to IDH-wild-type or to K27-mutant glioblastomas. Surgery consisted of total (12.7%), subtotal (35.6%), partial resection (33.9%) or biopsy (17.8%). The postoperative Karnofsky performance status was improved, stable and worsened in 22.4%, 43.9% and 33.7% of patients, respectively. Progression-free and overall survivals reached 5.1 months and 9.1 months, respectively. Compared to other surgical strategies, total or subtotal resection improved the Karnofsky performance status (33.3% vs 12.5%, p < 0.001), prolonged progression-free and overall survivals (6.5 vs 4.3 months, p = 0.015 and 16.7 vs 6.2 months, p < 0.001, respectively) and had a comparable complication rate (40.4% vs 31.1%, p = 0.29). After total or subtotal resection, the functional outcomes were correlated with age (p = 0.004) and cerebellar hemispheric tumor location (p < 0.001) but not brainstem infiltration (p = 0.16).

Conclusion: In selected patients, maximal resection of cerebellar glioblastoma is associated with improved onco-functional outcomes, compared with less invasive procedures.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00432-020-03474-6DOI Listing
January 2021

Alterations of cerebral microcirculation in peritumoral edema: feasibility of in vivo sidestream dark-field imaging in intracranial meningiomas.

Neurooncol Adv 2020 Jan-Dec;2(1):vdaa108. Epub 2020 Aug 27.

Creatis Lab, CNRS UMR 5220, INSERM U1206, Lyon 1 University, INSA Lyon, Lyon, France.

Background: Intracranial meningiomas display a variable amount of peritumoral brain edema (PTBE), which can significantly impact perioperative morbidity. The role of microcirculatory disturbances in the pathogenesis of PTBE is still debated. The aim of this study was to microscopically demonstrate and intraoperatively quantify, for the first time, the alterations to microcirculation in PTBE using sidestream dark-field (SDF) imaging.

Methods: Adult patients with WHO grade I meningiomas were recruited over a 9-month period and divided into 2 groups depending on the absence (NE group) or the presence (E group) of PTBE. In vivo intraoperative microcirculation imaging was performed in the peritumoral area before and after microsurgical resection.

Results: Six patients were included in the NE group and 6 in the E group. At the baseline in the NE group, there was a minor decrease in microcirculatory parameters compared to normal reference values, which was probably due to the mass effect. In contrast, microcirculatory parameters in the E group were significantly altered, affecting both vessel density and blood flow values, with a drop of approximately 50% of normal values. Surgical resection resulted in a quasi-normalization of microcirculation parameters in the NE group, whereas in the E group, even if all parameters statistically significantly improved, post-resection values remained considerably inferior to those of the normal reference pattern.

Conclusion: Our study confirmed significant alterations of microcirculatory parameters in PTBE in meningiomas. Further in vivo SDF imaging studies may explore the possible correlation between the severity of these microcirculatory alterations and the postoperative neurological outcome.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/noajnl/vdaa108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7542984PMC
August 2020

Arteriovenous malformation drained into a developmental venous anomaly: A case report and up-dated literature review.

Neurochirurgie 2020 Dec 10;66(6):471-476. Epub 2020 Oct 10.

Hospices civils de Lyon, hôpital neurologique Pierre-Wertheimer, department of neurosurgery, 59, boulevard Pinel, 69677 Bron, France.

Introduction: Although the association of developmental venous anomalies (DVAs) with cavernous malformations is well documented, the association with arteriovenous malformations (AVM) is unusual. The aim is herein to report an additional case and to review the concepts associated to these mixed malformations in order to guide patient management.

Methods: A case of AVM associated with a DVA was identified and a literature review was performed according to PRISMA guidelines.

Case Report: In an 18-year-old man presenting with sub-acute headache but with a normal neurological examination, the MRI-scan showed a right occipital DVA associated with hemosiderin spots evocative of earlier asymptomatic bleedings. The Digital Subtraction Angiography revealed a right parieto-occipital Spetzler-Martin Grade III AVM, fed by branches from the right middle and posterior cerebral arteries, with a superficial drainage flowing into a DVA that then joined the superior sagittal sinus. Multistep embolization was performed, leading to a partial reduction of the nidus, but preserving the DVA permeability. After a six-year follow-up. bleeding did not recur and the MRI aspect of the malformation was perfectly stable.

Conclusion: The co-occurrence of a DVA and an AVM is rare but has a higher bleeding risk than AVM alone (69% vs 38%) and must consequently be suspected when a DVA is revealed by a haemorrhage, in the absence of associated cavernoma. These mixed malformations represent a therapeutic challenge which has to be tailored to the venous anatomy and to the malformation Spetzler-Martin grade. DVA permeability should be preserved to avoid deleterious venous infarction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuchi.2020.08.003DOI Listing
December 2020

Surgical Site Infections after glioblastoma surgery: results of a multicentric retrospective study.

Infection 2021 Apr 9;49(2):267-275. Epub 2020 Oct 9.

Neurochirurgie, CHU de Limoges, Limoges, France.

Background: The effects of surgical site infections (SSI) after glioblastoma surgery on patient outcomes are understudied. The aim of this retrospective multicenter study was to evaluate the impact of SSI on the survival of glioblastoma patients.

Methods: Data from SSI cases after glioblastoma surgeries between 2009 and 2016 were collected from 14 French neurosurgical centers. Collected data included patient demographics, previous medical history, risk factors, details of the surgical procedure, radiotherapy/chemotherapy, infection characteristics, and infection management. Similar data were collected from gender- and age-paired control individuals.

Results: We used the medical records of 77 SSI patients and 58 control individuals. 13 were excluded. Our analyses included data from 64 SSI cases and 58 non-infected glioblastoma patients. Infections occurred after surgery for primary tumors in 38 cases (group I) and after surgery for a recurrent tumor in 26 cases (group II). Median survival was 381, 633, and 547 days in patients of group I, group II, and the control group, respectively. Patients in group I had significantly shorter survival compared to the other two groups (p < 0.05). The one-year survival rate of patients who developed infections after surgery for primary tumors was 50%. Additionally, we found that SSIs led to postoperative treatment discontinuation in 30% of the patients.

Discussion: Our findings highlighted the severity of SSIs after glioblastoma surgery, as they significantly affect patient survival. The establishment of preventive measures, as well as guidelines for the management of SSIs, is of high clinical importance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s15010-020-01534-0DOI Listing
April 2021

Surgical management for large vestibular schwannomas: a systematic review, meta-analysis, and consensus statement on behalf of the EANS skull base section.

Acta Neurochir (Wien) 2020 11 29;162(11):2595-2617. Epub 2020 Jul 29.

Department of Neurosurgery Service and Gamma Knife Center, University hospital of Lausanne and Faculty of Biology and Medicine, University of Lausanne, Rue du Bugnon 46, CH-1011, Lausanne, Switzerland.

Background And Objective: The optimal management of large vestibular schwannomas continues to be debated. We constituted a task force comprising the members of the EANS skull base committee along with international experts to derive recommendations for the management of this problem from a European perspective.

Material And Methods: A systematic review of MEDLINE database, in compliance with the PRISMA guidelines, was performed. A subgroup analysis screening all surgical series published within the last 20 years (January 2000 to March 2020) was performed. Weighted summary rates for tumor resection, oncological control, and facial nerve preservation were determined using meta-analysis models. This data along with contemporary practice patterns were discussed within the task force to generate consensual recommendations regarding preoperative evaluations, optimal surgical strategy, and follow-up management.

Results: Tumor classification grades should be systematically used in the perioperative management of patients, with large vestibular schwannomas (VS) defined as > 30 mm in the largest extrameatal diameter. Grading scales for pre- and postoperative hearing (AAO-HNS or GR) and facial nerve function (HB) are to be used for reporting functional outcome. There is a lack of consensus to support the superiority of any surgical strategy with respect to extent of resection and use of adjuvant radiosurgery. Intraoperative neuromonitoring needs to be routinely used to preserve neural function. Recommendations for postoperative clinico-radiological evaluations have been elucidated based on the surgical strategy employed.

Conclusion: The main goal of management of large vestibular schwannomas should focus on maintaining/improving quality of life (QoL), making every attempt at facial/cochlear nerve functional preservation while ensuring optimal oncological control, thereby allowing to meet patient expectations. Despite the fact that this analysis yielded only a few Class B evidences and mostly expert opinions, it will guide practitioners to manage these patients and form the basis for future clinical trials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00701-020-04491-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7550309PMC
November 2020

Surgical management of craniopharyngiomas in adult patients: a systematic review and consensus statement on behalf of the EANS skull base section.

Acta Neurochir (Wien) 2020 05 28;162(5):1159-1177. Epub 2020 Feb 28.

Department of Neurosurgery, University Hospital of Lausanne, Lausanne, Switzerland.

Background And Objective: Craniopharyngiomas are locally aggressive neuroepithelial tumors infiltrating nearby critical neurovascular structures. The majority of published surgical series deal with childhood-onset craniopharyngiomas, while the optimal surgical management for adult-onset tumors remains unclear. The aim of this paper is to summarize the main principles defining the surgical strategy for the management of craniopharyngiomas in adult patients through an extensive systematic literature review in order to formulate a series of recommendations.

Material And Methods: The MEDLINE database was systematically reviewed (January 1970-February 2019) to identify pertinent articles dealing with the surgical management of adult-onset craniopharyngiomas. A summary of literature evidence was proposed after discussion within the EANS skull base section.

Results: The EANS task force formulated 13 recommendations and 4 suggestions. Treatment of these patients should be performed in tertiary referral centers. The endonasal approach is presently recommended for midline craniopharyngiomas because of the improved GTR and superior endocrinological and visual outcomes. The rate of CSF leak has strongly diminished with the use of the multilayer reconstruction technique. Transcranial approaches are recommended for tumors presenting lateral extensions or purely intraventricular. Independent of the technique, a maximal but hypothalamic-sparing resection should be performed to limit the occurrence of postoperative hypothalamic syndromes and metabolic complications. Similar principles should also be applied for tumor recurrences. Radiotherapy or intracystic agents are alternative treatments when no further surgery is possible. A multidisciplinary long-term follow-up is necessary.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00701-020-04265-1DOI Listing
May 2020

Surgical management of Tuberculum sellae Meningiomas: Myths, facts, and controversies.

Acta Neurochir (Wien) 2020 03 13;162(3):631-640. Epub 2019 Dec 13.

Service of Neurosurgery, University Hospital of Lausanne (CHUV), Lausanne, Switzerland.

Background: The optimal management of tuberculum sellae (TS) meningiomas, especially the surgical strategy, continues to be debated along with several controversies that persist.

Methods: A task force was created by the EANS skull base section committee along with its members and other renowned experts in the field to generate recommendations for the surgical management of these tumors on a European perspective. To achieve this, the task force also reviewed in detail the literature in this field and had formal discussions within the group.

Results: The constituted task force dealt with the practice patterns that exist with respect to pre-operative radiological investigations, ophthalmological and endocrinological assessments, optimal surgical strategies, and follow-up management.

Conclusion: This article represents the consensually derived opinion of the task force with respect to the surgical treatment of tuberculum sellae meningiomas. Areas of uncertainty where further clinical research is required were identified.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00701-019-04114-wDOI Listing
March 2020

Minimal-Access Endoscopic Endonasal Management of Dysthyroid Optic Neuropathy: The Dysthone Study.

Neurosurgery 2019 12;85(6):E1059-E1067

Department of Neurosurgery, Pierre Wertheimer Neurological and Neurosurgical Hospital, Hospices Civils de Lyon, Lyon, France.

Background: Dysthyroid optic neuropathy (DON) is a devastating complication of thyroid eye disease. Corticosteroids are the primary medical treatment for DON, but some refractory patients may require surgical management.

Objective: To evaluate the efficacy of endoscopic endonasal decompression of the orbital apex in refractory DON.

Methods: This study included patients with refractory DON who underwent endoscopic endonasal decompression of the orbital apex from February 2015 to October 2016. A total of 23 orbital apices were decompressed across 17 patients. Visual acuity, ophthalmometry, tonometry, and visual field were evaluated at the preoperative, early and delayed postoperative stages. Statistical analyses were performed using RStudio software. A Wilcoxon test for matched data was performed to determine if there was a statistically significant difference between pre- and postsurgical treatment for the following items: visual acuity, proptosis, visual field, and intraocular pressure.

Results: Visual acuity improved in 69.5% of the cases with a mean gain of 2.5 points ± 1.6 (P < .05). Additionally, there was an 18.3% reduction in mean proptosis across all cases (P < .05) and a 13.7% decrease in intraocular pressure (P < .05) for all patients. Finally, visual field improved in 82.6% (P < .05) of the cases. The mean time for follow-up was of 6.28 ± 3.7 mo. There were 3 cases of transient postoperative rhinitis and 2 cases of transient diplopia. Two patients experienced recurrence at 4 and 8 mo, respectively.

Conclusion: Endoscopic endonasal decompression of the orbital apex significantly improves visual parameters. As a result, multidisciplinary screening for patients is crucial to ensure prompt surgical decompression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/neuros/nyz268DOI Listing
December 2019

Thyrotropin-secreting pituitary adenomas: a systematic review and meta-analysis of postoperative outcomes and management.

Pituitary 2019 Feb;22(1):79-88

Department of Neurosurgery, University Hospital of Lausanne, Lausanne, Switzerland.

Purpose: TSH-secreting pituitary adenomas are rare pituitary tumors. An efficient treatment is essential to limit the mortality and morbidity in untreated patients. The aim of this study is to summarize the evidence about the postoperative outcomes and management of this rare pathology.

Methods: A systematic search and meta-analysis of surgical series was performed.

Results: Our analysis included 23 articles (536 patients). No sex difference was observed and mean age at diagnosis was 45 years. Hyperthyroidism was reportedly clinical in 67% and biochemical in 90% of patients. Co-secretion of other pituitary hormones was present in 42% of cases. Macroadenomas were found in 79% of patients, showing in 44% and 30% of cases respectively extrasellar extension and cavernous sinus invasion. The pooled rate of postoperative biochemical remission was 69.7% and a gross total resection (GTR) was observed in 54% of patients. The extent of resection was significantly increased in microadenomas (p < 0.001) and cavernous sinus invasion was predictive of lower GTR rate (p < 0.001). A biochemical remission was achieved in 66% of patients after adjuvant radiation therapy and in 76% after adjuvant medical treatment. The combination of both allowed remission in 67% of cases. At final follow-up the overall biochemical remission rate was significantly improved (85.8%) when compared to the postoperative biochemical remission (p < 0.001).

Conclusion: When compared to the early postoperative period, at last follow-up biochemical remission was significantly greater (p < 0.001). GTR was achieved in half of patients; the size of tumor and cavernous sinus invasion determined the extent of resection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11102-018-0921-3DOI Listing
February 2019

Overcoming Challenges of Cranial Nerve Tractography: A Targeted Review.

Neurosurgery 2019 02;84(2):313-325

CREATIS Laboratory CNRS UMR5220, Inserm U1206, INSA-Lyon, University of Lyon 1, Lyon, France.

Background: 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.

Objective: To conduct and present a targeted review collecting all technical details and pointing out challenges and solutions in cranial nerve tractography.

Methods: A "targeted" review of the scientific literature was carried out using the MEDLINE database. We 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.

Results: 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.

Conclusion: 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.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/neuros/nyy229DOI Listing
February 2019

Delayed Posttraumatic Subacute Lumbar Subarachnoid Hematoma: Case Report and Review of the Literature.

World Neurosurg 2018 May 14;113:135-139. Epub 2018 Feb 14.

Department of Neurosurgery, Lyon University Hospital, Hospices Civils de Lyon, Bron, France; CREATIS Laboratory, Lyon University, Lyon, France. Electronic address:

Background: Traumatic spinal subarachnoid hematoma, associated or not with a concurrent subdural hematoma, has rarely been described. The evolution of such hematomas is heterogeneous. This study aims at defining the most accurate management, which is currently not standardized.

Case Description: A 20-year-old man, victim of a high-kinetic road accident 5 days before and with several nonneurologic nonsurgical vertebral fractures, experienced a sudden dorsolumbar pain radiating to his lower limbs. A rapidly progressive asymmetric paraparesis with loss of reflexes was noticed, associated with bilateral global hypoesthesia of the lower limbs and with acute urinary retention, whereas the anal tonicity was preserved (American Spinal Injury Association C). Magnetic resonance imaging scan revealed a conus medullaris compression at the level of the L1-L2 vertebrae by an intradural expansive mass. Immediate surgical decompression revealed a strictly subarachnoid hematoma. Venous bleeding was seen at the level of the conus medullaris and controlled. Pathologic examination of the clot excluded an underlying tumor or vascular abnormality. The complete coagulation profile was normal.

Conclusion: Six weeks after surgery, the neurologic examination revealed only a slight tactile hypoesthesia of the left thigh. With only 4 reported cases, purely subarachnoid spinal hematomas remain widely rarer than epidural hematomas. The reported case possesses a certain number of peculiarities: young age, pure subarachnoid location, lumbar location, occurrence after a car accident, subacute onset, and excellent neurologic recovery. In our opinion, a symptomatic subarachnoid spinal hematoma should be surgically evacuated at the early phase so neurologic recovery can be expected.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2018.02.035DOI Listing
May 2018

Orbital Cavernous Hemangioma Causing Spontaneous Compressive Hemorrhage.

J Craniofac Surg 2018 May;29(3):706-708

Maxillo-Facial Unit, Hôpital de la Croix Rousse, CHU Lyon, Lyon, France.

Cavernous hemangiomas are the most common tumors of the posterior cone of the orbit in adults. They are discovered in a fortuitous manner or in front of the appearance of a progressive exophthalmia.The authors report through a complete literature review (PubMed) patients of retro-orbital cavernous hemangioma revealed by spontaneous compressional hemorrhage from 1984 to 2017.This review is illustrated by a case of sharp decrease in visual acuity secondary to orbital cavernous hemangioma hemorrhage.The authors detail the management and the evolution of all these patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/SCS.0000000000004285DOI Listing
May 2018

Liponeurocytoma of the Cerebellopontine Angle.

World Neurosurg 2018 Apr 8;112:18-24. Epub 2018 Jan 8.

Skull Base Surgery Unit, Department of Neurosurgery B, University Hospital of Lyon, Hospices Civils de Lyon, Lyon, France; CREATIS Laboratory, CNRS UMR5220, INSERM U1206, Lyon 1 University, INSA, Lyon, France. Electronic address:

Background: Liponeurocytoma is a very rare tumor classified as grade II (neuronal and mixed neuronal-glial tumors) according to 2016 World Health Organization classification of tumors of the central nervous system. The median age at detection is 50 years, and the most frequent location is the posterior cranial fossa, especially within the cerebellar hemispheres; liponeurocytomas arising in the cerebellopontine angle (CPA) are exceptional.

Case Description: Here we report the clinical, radiological, and pathological characteristics of a CPA liponeurocytoma in a 35-year-old woman, as well as a review of the literature. This unusual cisternal location raises the issue of the differential imaging diagnosis with much more common CPA tumors (e.g., meningiomas, vestibular schwannomas, ependymomas, epidermoid cyst, hemangioblastomas, medulloblastomas).

Conclusion: To the best of our knowledge, 59 cases of cerebellar liponeurocytomas have been reported to date, which include only 6 cases of CPA liponeurocytomas. Treatment relies on total removal whenever possible, with an excellent prognosis, but a high MIB-1 index (>10%) and/or incomplete tumor resection are the main adverse prognostic factors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2018.01.012DOI Listing
April 2018

Pathogenesis of peri-tumoral edema in intracranial meningiomas.

Neurosurg Rev 2019 Mar 24;42(1):59-71. Epub 2017 Aug 24.

Laboratory CREATIS - CNRS UMR5220 - INSERM U1206 - Lyon 1 University - INSA, Lyon, France.

Peri-tumoral edema in intracranial meningiomas occurs frequently and obviously impacts the morbidity and mortality of these predominantly benign neoplasms. Several causative factors (age, gender, volume, location…) have been unsuccessfully investigated. Despite recent progresses in metabolic imaging and molecular biology, the pathogenesis of peri-tumoral edema remains debated. Hypotheses include vascular endothelial growth factor, metalloproteinases and interleukins among many others. It is probable that this pathogenesis encompasses all these factors with different levels. The current review aims to shed the light on the investigated factors involved in the pathogenesis of peri-tumoral edema in meningiomas and identify the potential therapeutic targets.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10143-017-0897-xDOI Listing
March 2019

The 360 photography: a new anatomical insight of the sphenoid bone. Interest for anatomy teaching and skull base surgery.

Surg Radiol Anat 2017 Jan 2;39(1):17-22. Epub 2016 Jun 2.

Department of Anatomy, University of Lyon 1, 8 Avenue Rockefeller, 69003, Lyon, France.

Skull base architecture is tough to understand because of its 3D complex shape and its numerous foramen, reliefs or joints. It is especially true for the sphenoid bone whom central location hinged with most of skull base components is unique. Recently, technological progress has led to develop new pedagogical tools. This way, we bought a new real-time three-dimensional insight of the sphenoid bone that could be useful for the teacher, the student and the surgeon. High-definition photography was taken all around an isolated dry skull base bone prepared with Beauchêne's technique. Pictures were then computed to provide an overview with rotation and magnification on demand. From anterior, posterior, lateral or oblique views and from in out looks, anatomical landmarks and subtleties were described step by step. Thus, the sella turcica, the optic canal, the superior orbital fissure, the sphenoid sinus, the vidian canal, pterygoid plates and all foramen were clearly placed relative to the others at each face of the sphenoid bone. In addition to be the first report of the 360 Photography tool, perspectives are promising as the development of a real-time interactive tridimensional space featuring the sphenoid bone. It allows to turn around the sphenoid bone and to better understand its own special shape, numerous foramen, neurovascular contents and anatomical relationships. This new technological tool may further apply for surgical planning and mostly for strengthening a basic anatomical knowledge firstly introduced.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00276-016-1702-1DOI Listing
January 2017

Pathogenesis of Delayed Tension Intraventricular Pneumocephalus in Shunted Patient: Possible Role of Nocturnal Positive Pressure Ventilation.

World Neurosurg 2016 Jan 9;85:365.e17-20. Epub 2015 Sep 9.

Department of Neurosurgery B, Pierre Wertheimer Neurological and Neurosurgical Hospital, Hospices Civils de Lyon, France. Electronic address:

Background: Delayed intraventricular pneumocephalus is a very rare and potentially serious complication of ventriculoperitoneal shunt. It can occur several months or years after shunting. Its pathogenesis is unclear. We herein discuss the underlying mechanisms and particularly the possible role of positive pressure ventilation.

Case Description: A 60 year-old man presented with a lateral ventricle neurocytoma microsurgically resected complicated by a late-onset (15 months) postoperative hydrocephalus requiring an adjustable ventriculoperitoneal (VP) shunt. One month later, the patient was diagnosed with a sleep apnea and required a continuous positive airway pressure (CPAP) device. A few weeks afterward the patient presented with headaches and alteration of consciousness. CT-Scan revealed a massive intraventricular pneumocephalus associated with a millimetric left petrous bone defect. A transient breakout of the positive ventilation and a subtemporal surgical repair of the defect led to the rapid resolution of the pneumocephalus.

Discussion: Delayed intraventricular pneumocephalus requires two conditions: a VP shunt and an osteodural defect. The CPAP may play an important trigger role in the pathogenesis of this complication through a ball valve mechanism. The management relies on transient suspension of the positive ventilation and the surgical repair of the identified defect with or without pressure adjustments of the valve.

Conclusion: Intraventricular pneumocephalus is a potentially serious complication of patients with a VP shunt and receiving positive pressure ventilation. The introduction of a CPAP device must be discussed with the neurosurgeon beforehand in shunted patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2015.09.001DOI Listing
January 2016

Anatomic comparison of anterior petrosectomy versus the expanded endoscopic endonasal approach: interest in petroclival tumors surgery.

Surg Radiol Anat 2015 Dec 12;37(10):1199-207. Epub 2015 Jun 12.

Skull Base Multi-disciplinary Unit, Department of Neurosurgery B, Neurological Hospital Pierre Wertheimer, Hospices Civils de Lyon, 59 Bd Pinel, 69677, Lyon Cedex, France.

Purpose: Since the petroclival region is deep-seated with close neurovascular relationships, the removal of petroclival tumors still represents a fascinating surgical challenge. Although the classical anterior petrosectomy (AP) offers a meaningful access to this petroclival region, the expanded endoscopic endonasal approach (EEEA) recently leads to overcome difficulties from trans-cranial approaches. Herein, we present an anatomic comparison of AP versus EEEA. We aim to describe the limits of these both approaches helping the choice of the optimal surgical route for petroclival tumors.

Methods: Six fresh cadaveric heads were harvested and injected with colored latex. Each approach was step-by-step detailed until its final surgical exposure.

Results: The AP provided a narrow direct supero-lateral access to the petroclival area that can also reach the cavernous sinus, the retrochiasmatic region and perimesencephalic cisterns. However, this corridor anterior to the internal acoustic meatus passed on each side of the trigeminal nerve. Moreover, tumor extensions toward the foramen jugularis, inside the clivus or behind the internal acoustic meatus were difficult to control. The EEEA brought a straightforward access to the clivus but the petrous apex was hidden behind the internal carotid artery. Several variants were described: a medial transclival, a lateral through the Meckel's cave and an inferior trans-pterygoid route. Elsewhere, tumor extension behind the internal acoustic meatus or above the tentorium could not be satisfactorily assessed.

Discussion And Conclusion: PA and EEEA have their own limits in reaching the petroclival region in accordance with the tumor characteristics. The AP should be preferred for radical removal of middle-sized petrous apex intradural tumors like meningiomas. The EEEA would be of interest for extradural midline tumors like chordomas or for petrous apex cysts drainage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00276-015-1497-5DOI Listing
December 2015

Total removal of a trigeminal schwannoma via the expanded endoscopic endonasal approach. Technical note.

Acta Neurochir (Wien) 2015 Jun 7;157(6):935-8; discussion 938. Epub 2015 Apr 7.

Multidisciplinary Skull Base Unit, Department of Neurosurgery B, Neurological Hospital Pierre Wertheimer, Hospices Civils de Lyon, 59 Bd Pinel, 69677, Lyon Cedex, France,

Background: Because of their deep location surrounded by closed numerous neurovascular structures, skull base tumors of the cavernous sinus are still difficult to manage. Recently, the endoscopic endonasal approach commonly used for pituitary tumor resection has been "expanded" to the parasellar, infratemporal and orbital compartments with some advantages compared to the intracranial route.

Methods: The authors reported the case of a 49-year-old male presenting a large extradural tumor of the left cavernous sinus with extensions toward the orbit, sphenoid sinus and infratemporal fossa. His ophthalmological examination was normal, and the body CT scan revealed no primary neoplasm.

Results: In this operative video, the approach is described step by step with surgical nuances. The endoscopy provided a close-up panoramic view and various angles of vision. Also, it avoided an invasive craniotomy, cerebral retraction and cranial nerves damages. Thus, it allowed the total removal of this tumor originating from the maxillary branch of the trigeminal nerve. The pathologic examination confirmed a schwannoma.

Conclusion: The expanded endoscopic endonasal approach provides an interesting corridor to cavernous sinus tumors with satisfactory control of extensions inferiorly toward the infratemporal fossa, anteriorly via the superior orbital fissure and medially within the sphenoid. Finally, the skull base surgeon has to master this anterior endoscopic route as well as all the other "open" transcranial skull base approaches to propose the best surgical route fitting the tumor characteristics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00701-015-2409-5DOI Listing
June 2015

Which Routes for Petroclival Tumors? A Comparison Between the Anterior Expanded Endoscopic Endonasal Approach and Lateral or Posterior Routes.

World Neurosurg 2015 Jun 17;83(6):929-36. Epub 2015 Feb 17.

Skull Base Multidisciplinary Unit, Department of Neurosurgery, Neurological Hospital Pierre Wertheimer, Lyon Cedex, France.

Objective: Petroclival tumors remain a surgical challenge. Classically, the retrosigmoid approach (RSA) has long been used to reach such tumors, whereas the anterior petrosectomy (AP) has been proposed to avoid crossing cranial nerves. More recently, the endoscopic endonasal approach has been "expanded" (i.e., EEEA) to the petroclival region. We aimed to compare these 3 approaches to help in the surgical management of petroclival tumors.

Methods: Petroclival approaches were performed on 5 specimens after they were prepared with formaldehyde colored via latex injection.

Results: The EEEA provides a simple straightforward route to the clivus, but reaching the petrous apex requires the surgeon to circumvent the internal carotid artery either via a medial transclival, an inferior transpterygoid, or a lateral variant through the Meckel's cave. In contrast, the AP offers a narrow direct superolateral access to the petroclival region crossed by the trigeminal nerve. Finally, the RSA provides a wide simple and quick exposure of the cerebellopontine angle, but access to the petroclival region needs the surgeon to deal with the V(th) to XI(th) cranial nerves.

Discussion/conclusion: The EEEA should be preferred for extradural midline tumors (chordomas, chondrosarcomas) or for cystic lesions when drainage is essential. The AP could be optimal for the radical removal of intradural vascularized tumors (meningiomas) with intrapetrous or supratentorial extensions. The RSA retains an advantage for small or cystic tumors near the internal acoustic meatus. The skull base surgeon has to master all of these routes to choose the more appropriate one according to the surgical objective, the tumor characteristics, and the patient's medical status.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2015.02.003DOI Listing
June 2015

Response to: "considerations about endoscopic endonasal optic nerve and orbital apex decompression".

Acta Neurochir (Wien) 2015 Apr 5;157(4):631-2. Epub 2015 Feb 5.

Multidisciplinary Skull Base Surgery Unit, Department of Neurosurgery B, Pierre Wertheimer Neurological and Neurosurgical Hospital, Hospices Civils de Lyon, 59 Boulevard Pinel, 69677, Lyon Cedex, France,

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00701-015-2357-0DOI Listing
April 2015

Endoscopic endonasal optic nerve and orbital apex decompression for nontraumatic optic neuropathy: surgical nuances and review of the literature.

Neurosurg Focus 2014 ;37(4):E19

Skull Base Surgery Unit, Department of Neurosurgery B, Pierre Wertheimer Neurological and Neurosurgical Hospital, Hospices Civils de Lyon.

Object: While several approaches have been described for optic nerve decompression, the endoscopic endonasal route is gaining favor because it provides excellent exposure of the optic canal and the orbital apex in a minimally invasive manner. Very few studies have detailed the experience with nontraumatic optic nerve decompressions, whereas traumatic cases have been widely documented. Herein, the authors describe their preliminary experience with endoscopic endonasal decompression for nontraumatic optic neuropathies (NONs) to determine the procedure's efficacy and delineate its potential indications and limits.

Methods: The medical reports of patients who had undergone endoscopic endonasal optic nerve and orbital apex decompression for NONs at the Lyon University Neurosurgical Hospital in the period from January 2012 to March 2014 were reviewed. For all cases, clinical and imaging data on the underlying pathology and the patient, including demographics, preoperative and 6-month postoperative ophthalmological assessment results, symptom duration, operative details with video debriefing, as well as the immediate and delayed postoperative course, were collected from the medical records.

Results: Eleven patients underwent endoscopic endonasal decompression for NON in the multidisciplinary skull base surgery unit of the Lyon University Neurosurgical Hospital during the 27-month study period. The mean patient age was 53.4 years, and there was a clear female predominance (8 females and 3 males). Among the underlying pathologies were 4 sphenoorbital meningiomas (36%), 3 optic nerve meningiomas (27%), and 1 each of trigeminal neuroma (9%), orbital apex meningioma (9%), ossifying fibroma (9%), and inflammatory pseudotumor of the orbit (9%). Fifty-four percent of the patients had improved visual acuity at the 6-month follow-up. Only 1 patient whose sphenoorbital meningioma had been treated at the optic nerve atrophy stage continued to worsen despite surgical decompression. The 2 patients presenting with preoperative papilledema totally recovered. One case of postoperative epistaxis was successfully treated using balloon inflation, and 1 case of air swelling of the orbit spontaneously resolved.

Conclusions: Endoscopic endonasal optic nerve decompression is a safe, effective, and minimally invasive technique affording the restoration of visual function in patients with nontraumatic compressive processes of the orbital apex and optic nerve. The timing of decompression remains crucial, and patients should undergo such a procedure early in the disease course before optic atrophy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3171/2014.7.FOCUS14303DOI Listing
June 2015

How I do it: the endoscopic endonasal optic nerve and orbital apex decompression.

Acta Neurochir (Wien) 2014 Oct 22;156(10):1891-6. Epub 2014 Aug 22.

Skull Base Surgery Unit - Department of Neurosurgery B, Pierre Wertheimer Neurological and Neurosurgical Hospital - Hospices Civils de Lyon, Lyon, France,

Background: With the refinement of the technique, endoscopic endonasal surgery increases its field of indications. The orbital compartment is among the locations easily reached through the nostril. This anteromedial approach has been described primarily for inflammatory or traumatic diseases, with few data for tumoral diseases.

Method: Since 2010, this route has been used at our institution either for decompression or for biopsy of orbital tumoral diseases.

Findings/conclusions: Even if further studies are warranted, this strategy proved to be beneficial for patients, with improvements in visual outcome. In this article, the authors summarize their technique and their experience with endonasal endoscopic orbital decompression.

Key Points: Nasal and sphenoidal anatomies determine the feasibility and risks for doing an efficient medial optic or orbit decompression. • Techniques and tools used are those developed for pituitary surgery. • A middle turbinectomy and posterior ethmoidectomy are mandatory to expose the medial wall of the orbit. • The Onodi cell is a key marker for the optic canal and must be opened up with caution. • The lamina papyracea is opened first with a spatula and the optic canal opened up by a gentle drilling under continuous irrigation from distal to proximal. • Drilling might always be used under continuous irrigation to avoid overheating of the optic nerve. An ultrasonic device can be used as well. • The nasal corridor is narrow and instruments may hide the infrared neuronavigation probe. To overcome this issue, a magnetic device could be useful. • Doppler control could be useful to locate the ICA. • The optic canal must be opened up from the tuberculum of the sella to the orbital apex and from the planum (anterior cranial fossa) to the lateral OCR or ICA canal • At the end of the procedure, the optic nerve becomes frequently pulsatile, which is a good marker of decompression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00701-014-2199-1DOI Listing
October 2014

The endoscopic endonasal approach to the Meckel's cave tumors: surgical technique and indications.

World Neurosurg 2014 Dec 12;82(6 Suppl):S155-61. Epub 2014 Aug 12.

Department of Neurosurgery A, Pierre Wertheimer Hospital, Hospices Civils de Lyon, Lyon 1 University, Lyon, France.

Many benign and malignant tumors as well as other inflammatory or vascular diseases may be located in the areas of Meckel's cave or the cavernous sinus. Except for typical features such as for meningiomas, imaging may not by itself be sufficient to choose the best therapeutic option. Thus, even though modern therapy (chemotherapy, radiotherapy, or radiosurgery) dramatically reduces the field of surgery in this challenging location, there is still some place for surgical biopsy or tumor removal in selected cases. Until recently, the microscopic subtemporal extradural approach with or without orbitozygomatic removal was classically used to approach Meckel's cave but with a non-negligible morbidity. Percutaneous biopsy using the Hartel technique has been developed for biopsy of such tumors but may fail in the case of firm tumors, and additionally it is not appropriate for anterior parasellar tumors. With the development of endoscopy, the endonasal route now represents an interesting alternative approach to Meckel's cave as well as the cavernous sinus. Through our experience, we describe the modus operandi and discuss what should be the appropriate indication of the use of the endonasal endoscopic approach for Meckel's cave disease in the armamentarium of the skull base surgeon.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2014.08.003DOI Listing
December 2014

Endoscope-assisted retrosigmoid resection of a medium size vestibular schwannoma tumor model: a cadaveric study.

Clin Neurol Neurosurg 2014 Apr 18;119:35-8. Epub 2014 Jan 18.

Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Columbus, USA. Electronic address:

Objective: To demonstrate a flexible endoscope assisted technique to perform microsurgical resection using a retrosigmoid approach of an artificial polymer tumor model that mimics a medium size (15-20mm diameter) vestibular schwannoma.

Methods: Twelve bilateral retrosigmoid dissections were performed in 6 glutaraldehyde embalmed, colored silicone injected, adult cadaveric heads. Using a standard retrosigmoid approach, we first implanted the tumor model at the cerebellopontine angle (CPA) and then we resected the tumor under simultaneous endoscopic and microscopic visualizations. The resection was performed by first creating a corridor by removing the lower portion of the tumor and then by inserting through the same corridor the flexible endoscope mounted on a surgical instrument in order to accomplish early visualization of the VII-VIII complex. This early visualization of the VII-VIII complex made possible expeditious removal of the model with preservation of the VII-VIII complex.

Results: We were able to successfully implant the artificial tumor in all the specimens. The post-tumor implantation CT scan confirmed the optimal CPA location of the model with its intra-porus extension. The exposure of the facial and the adjoining neuro-vascular structures was excellent during all stages of the surgical removal and was accomplished with minimal cerebellar retraction, under intermittent endoscopic-assisted control. Early visualization of the facial and vestibular cochlear nerves complex led to unhindered removal of the tumor model.

Conclusions: The endoscopic-assisted microsurgical removal of a tumor model simulating a medium size vestibular schwannoma was feasible in our tumor model study emulating real surgery. Visualization of the acousticofacial bundle at the early stage of the surgical removal should theoretically decrease the risk of its inadvertent injuries as well as facilitate complete removal of the tumor. Clinical studies to validate this laboratory study are necessary.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clineuro.2013.12.023DOI Listing
April 2014

Non-functioning pituitary macro-incidentalomas benefit from early surgery before becoming symptomatic.

Clin Neurol Neurosurg 2013 Dec 22;115(12):2514-20. Epub 2013 Oct 22.

Département de Neurochirurgie, Centre Hospitalier Universitaire Vaudois, Université de Lausanne, Lausanne, Switzerland. Electronic address:

Objective: Pituitary incidentalomas (PIs) constitute an increasingly clinical problem. While the therapeutic management is well defined for symptomatic non-functioning PIs (NFPIs), a controversy still exists for asymptomatic macro-NFPIs between surgery and a "wait and see" approach. The aim of this study is to compare surgical results between symptomatic and asymptomatic macro-NFPIs.

Methods: We conducted a retrospective study on 76 patients with newly diagnosed symptomatic and asymptomatic macro-NFPIs operated on between 2001 and 2010. We compared age, tumor size and surgical results between these two patient groups.

Results: After the initial evaluation, 48 patients were found to be symptomatic. Gross total removal (GTR) rate was significantly higher in asymptomatic (82%) than in symptomatic patients (58%; p=0.03). Gross total removal was strongly associated with Knosp's classification (p=0.01). Postoperative endocrinological impairment was significantly associated with the existence of preoperative symptoms (p=0.03). It was 10 times less frequent in the asymptomatic group. In symptomatic patients, postoperative visual and endocrinological impairment were present in 49% and 78% versus 0% and 14% in asymptomatic patients respectively.

Conclusions: The endocrinological and visual outcome was better in those patients who underwent surgery for asymptomatic tumors. The extent of tumor resection was also significantly greater in smaller tumors. It would therefore be appropriate to offer surgery to patients with asymptomatic macro-NFPIs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clineuro.2013.10.007DOI Listing
December 2013

The endoscopic intraventricular management of pineal cysts: a minimally invasive modus operandi.

Acta Neurochir (Wien) 2013 Oct 22;155(10):1901-5. Epub 2013 Aug 22.

Department of Neurosurgery, Pierre Wertheimer Neurological and Neurosurgical Hospital, Hospices Civils de Lyon, University Claude Bernard, Lyon, France,

Background: The management of pineal cysts is still debatable, especially for asymptomatic incidental ones. For symptomatic cysts associated with hydrocephalus, the surgical management is mandatory and may include either classical microsurgical approaches to the pineal region or endoscopic trans-ventricular approaches in a minimally invasive philosophy.

Method: The authors expose a stepwise technique to treat a pineal cyst associated with an obstructive hydrocephalus in one procedure gathering a third ventriculostomy followed by an intraventricular marsupialisation of the pineal cyst.

Conclusion: This endoscopic approach allows the treatment of the hydrocephalus and the pineal cyst in one short minimally invasive procedure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00701-013-1849-zDOI Listing
October 2013

Individual patient data systematic review and meta-analysis of optic nerve sheath diameter ultrasonography for detecting raised intracranial pressure: protocol of the ONSD research group.

Syst Rev 2013 Aug 6;2:62. Epub 2013 Aug 6.

Université Claude Bernard Lyon 1, 69003 Lyon, France.

Background: The purpose of the optic nerve sheath diameter (ONSD) research group project is to establish an individual patient-level database from high quality studies of ONSD ultrasonography for the detection of raised intracranial pressure (ICP), and to perform a systematic review and an individual patient data meta-analysis (IPDMA), which will provide a cutoff value to help physicians making decisions and encourage further research. Previous meta-analyses were able to assess the diagnostic accuracy of ONSD ultrasonography in detecting raised ICP but failed to determine a precise cutoff value. Thus, the ONSD research group was founded to synthesize data from several recent studies on the subject and to provide evidence on the diagnostic accuracy of ONSD ultrasonography in detecting raised ICP.

Methods: This IPDMA will be conducted in different phases. First, we will systematically search for eligible studies. To be eligible, studies must have compared ONSD ultrasonography to invasive intracranial devices, the current reference standard for diagnosing raised ICP. Subsequently, we will assess the quality of studies included based on the QUADAS-2 tool, and then collect and validate individual patient data. The objectives of the primary analyses will be to assess the diagnostic accuracy of ONSD ultrasonography and to determine a precise cutoff value for detecting raised ICP. Secondly, we will construct a logistic regression model to assess whether patient and study characteristics influence diagnostic accuracy.

Discussion: We believe that this IPD MA will provide the most reliable basis for the assessment of diagnostic accuracy of ONSD ultrasonography for detecting raised ICP and to provide a cutoff value. We also hope that the creation of the ONSD research group will encourage further study.

Trial Registration: PROSPERO registration number: CRD42012003072.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/2046-4053-2-62DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3751128PMC
August 2013

Beyond the pineal gland assumption: a neuroanatomical appraisal of dualism in Descartes' philosophy.

Authors:
Moncef Berhouma

Clin Neurol Neurosurg 2013 Sep 3;115(9):1661-70. Epub 2013 Apr 3.

Department of Neurosurgery B, Pierre Wertheimer Neurological and Neurosurgical Hospital, Hospices Civils de Lyon, Lyon Cedex 03, France.

Objective: The problem of the substantial union of the soul and the body and therefore the mechanisms of interaction between them represents the core of the Cartesian dualistic philosophy. This philosophy is based upon a neuroanatomical obvious misconception, consisting mainly on a wrong intraventricular position of the pineal gland and its capacity of movement to act as a valve regulating the flow of animal spirits. Should we consider the Cartesian neurophysiology as a purely anatomical descriptive work and therefore totally incorrect, or rather as a theoretical conception supporting his dualistic philosophy?

Method: From the various pre-Cartesian theories on the pineal organ, we try to explain how Descartes used his original conception of neuroanatomy to serve his dualistic philosophy. Moreover, we present an appraisal of the Cartesian neuroanatomical corpus from an anatomical but also metaphysical and theological perspectives.

Results: A new interpretation of Descartes' writings and an analysis of the secondary related literature shed the light on the voluntary anatomical approximations aiming to build an ad hoc neurophysiology that allows Descartes' soul-body theory.

Conclusion: By its central position within the brain mass and its particular shape, the pineal gland raised diverse metaphysical theories regarding its function, but the most original theory remains certainly its role as the seat of soul in René Descartes' philosophy and more precisely the organ where soul and body interact. The author emphasizes on the critics raised by Descartes' theories on the soul-body interaction through the role of the pineal gland.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clineuro.2013.02.023DOI Listing
September 2013

Shortening the learning curve in endoscopic endonasal skull base surgery: a reproducible polymer tumor model for the trans-sphenoidal trans-tubercular approach to retro-infundibular tumors.

Clin Neurol Neurosurg 2013 Sep 5;115(9):1635-41. Epub 2013 Mar 5.

Dardinger Microneurosurgical Skull Base Lab, Ohio State University Medical Center, Columbus, OH 43210, USA.

Background: Endoscopic endonasal skull base surgery attracts an increasing number of young neurosurgeons. This recent technique requires specific technical skills for the approaches to non-pituitary tumors (expanded endoscopic endonasal surgery). Actual residents' busy schedules carry the risk of compromising their laboratory training by limiting significantly the dedicated time for dissections.

Objective: To enhance and shorten the learning curve in expanded endoscopic endonasal skull base surgery, we propose a reproducible model based on the implantation of a polymer via an intracranial route to provide a pathological retro-infundibular expansive lesion accessible to a virgin expanded endoscopic endonasal route, avoiding the ethically-debatable need to hundreds of pituitary cases in live patients before acquiring the desired skills.

Methods: A polymer-based tumor model was implanted in 6 embalmed human heads via a microsurgical right fronto-temporal approach through the carotido-oculomotor cistern to mimic a retro-infundibular tumor. The tumor's position was verified by CT-scan. An endoscopic endonasal trans-sphenoidal trans-tubercular trans-planum approach was then carried out on a virgin route under neuronavigation tracking.

Results: Dissection of the tumor model from displaced surrounding neurovascular structures reproduced live surgery's sensations and challenges. Post-implantation CT-scan allowed the pre-removal assessment of the tumor insertion, its relationships as well as naso-sphenoidal anatomy in preparation of the endoscopic approach.

Conclusion: Training on easily reproducible retro-infundibular approaches in a context of pathological distorted anatomy provides a unique opportunity to avoid the need for repetitive live surgeries to acquire skills for this kind of rare tumors, and may shorten the learning curve for endoscopic endonasal surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clineuro.2013.02.013DOI Listing
September 2013