Jaafar Basma

Mobilization of the transcavernous oculomotor nerve during basilar aneurysm surgery: biomechanical bases for better outcome.

BACKGROUND: The transcavernous approach adds a significant exposure advantage in basilar aneurysm surgery. However, one of its frequently reported side effects is postoperative oculomotor nerve palsy. OBJECTIVE: To present the technique of mobilizing the oculomotor nerve throughout its intracranial course and to analyze its consequences on the nerve tension and clinical outcome. METHODS: The oculomotor nerve is mobilized from its mesencephalic origin to the superior orbital fissure. Its degree of mobility, related to the imposed pulling force, was measured in 11 cadaveric nerves. Tension was mathematically deduced and compared before and after mobilizing of the cavernous segment. One hundred four patients treated for basilar aneurysms with the orbitozygomatic pretemporal transcavernous approach were followed up for a 1-year period and evaluated for postoperative oculomotor nerve palsy. RESULTS: Releasing the transcavernous segment compared to cisternal mobilization alone resulted in a significant increase in freedom of mobility from 4 to 7.9 mm (P < .001) and in a significant decrease in tension from 0.8 to 0.5 N (P = .006). Ninety-nine percent of aneurysms treated with this technique were amenable to neck clipping, and a total of 84% of patients had a good postoperative outcome (modified Rankin Scale score, 0-2). All patients showed direct postoperative palsy; however, 97% had a complete recovery by 9 months. Only 3 patients had a persistent diplopia on medial gaze, which was corrected with prism glasses. CONCLUSION: Mobilization of the transcavernous oculomotor nerve results in better maneuverability and less tension on the nerve, which lead to successful surgical treatment and favorable oculomotor outcome.

Epidural skull base approach for dural arteriovenous fistulas (DAVF) of the anterior and middle cranial fossa.

Epidural skull base approach for dural arteriovenous fistulas (DAVF) of the anterior and middle cranial fossa

Minimizing Collateral Brain Injury Using a Protective Layer of Fibrin Glue: Technical Note

BACKGROUND Neurosurgical procedures expose the brain surface to a constant risk of collateral injury. We describe a technique where the brain surface is covered with a protective layer of fibrin glue and discuss its advantages. METHODS A thin layer of fibrin glue was applied on the brain surface after its exposure in 34 patients who underwent different craniotomies for tumoral and vascular lesions. Data of 35 more patients who underwent standard microsurgical technique were collected as a control group. Cortical and pial injuries were evaluated using an intraoperative visual scale. Eventual abnormal signals at the early postoperative T2-weighted fluid-attenuated inversion recovery (T2FLAIR) magnetic resonance imaging (MRI) sequences were evaluated in oncological patients. RESULTS Total pial injury was noted in 63% of cases where fibrin glue was not used. In cases where fibrin glue was applied, a significantly lower percentage of 26% (P < 0.01) had pial injuries. Only 9% had injuries in areas covered with fibrin glue (P < 0.0001). Early postoperative T2FLAIR MRI confirmed the differences of altered signal around the surgical field in the two populations. CONCLUSION We propose beside an appropriate and careful microsurgical technique the possible use of fibrin glue as alternative, safe, and helpful protection during complex microsurgical dissections. Its intrinsic features allow the neurosurgeon to minimize the cortical manipulation preventing minor collateral brain injury.

Extended Retrosigmoid Approach for the Resection of a Pontomedullary Junction Cavernous Malformation

Objectives  To describe an extended retrosigmoid approach for the resection of a cavernoma involving the ponto-medullary junction, with emphasis on the microsurgical anatomy and technique. Design  A retrosigmoid craniotomy is performed in the lateral decubitus position and the sigmoid sinus exposed. After opening the dura, sutures are placed medial to the sinus to allow its gentle mobilization. Cerebrospinal fluid (CSF) is drained from the cisterna magna, and cerebellopontine cistern, and dynamic retraction is used over the cerebellum. Subarachnoid dissection of the cerebellopontine angle gives access to cranial nerves IX/X, VII/VIII, and VI. Inspection of the pontomedullary junction medial to the facial nerve reveals hemosiderin staining in that region. A small pial opening is made, exposing the hemorrhagic cavity. The cavernous malformation is then identified, dissected circumferentially, and resected. Photographs of the region are borrowed from Dr Rhotons laboratory to illustrate the microsurgical anatomy. Participants  The senior author performed the surgery. The video was edited by Drs. J.B. and V.N. Outcome Measures  Outcome was assessed with extent of resection and postoperative neurological function. Results  A gross total resection of the lesion was achieved. The patient did not develop any postoperative deficits. Conclusion  Understanding the microsurgical anatomy of the cerebellopontine angle and meticulous microneurosurgical technique are necessary to achieve a complete resection of a brainstem cavernoma. The extended retrosigmoid approach provides an adequate corridor to the pontomedullary junction. The link to the video can be found at: https://youtu.be/FIKixWJT75w .

Orbitopterional Approach with Extradural Clinoidectomy for the Resection of a Tuberculum Sellae Meningioma: Adapting the Strategy to the Microsurgical and Pathological Anatomy

Objectives To describe the orbitopterional approach with extradural clinoidectomy for the resection of a tuberculum sellae meningioma, with an emphasis on the microsurgical and pathological anatomy of such lesions. Design After completing the orbitopterional craniotomy in one piece, the optic nerve is identified extradurally, unroofed, and the clinoid process resected. The falciform ligament is divided and the optic nerve is decompressed extradurally. Opening the frontotemporal dura exposes the tumor in the subfrontal region. The tumor is followed along the ipsilateral and contralateral optic nerves, and its dural tail is cut and coagulated at the level of the tuberculum. Care is taken to preserve the optic nerve perforators during the dissection. Photographs of the region are borrowed from Dr Rhotons laboratory to illustrate the microsurgical anatomy. Participants The surgery was performed by the senior author assisted by Dr. Jaafar Basma, neurosurgery fourth‐year resident. The video was edited by Dr. Vincent Nguyen, neurosurgery third‐year resident. Outcome Measures Outcome was assessed with the extent of resection and visual symptoms. Results A near‐total resection of the tumor was achieved. A small part of tumor significantly adherent to the optic nerve was intentionally left behind. The patient had a stable vision examination postoperatively. Conclusions Understanding the microsurgical anatomy of the suprasellar region and the pathological anatomy of the tuberculum sellae meningioma is necessary to achieve a good resection of these tumors while preserving functionality of the optic apparatus. The orbitopterional approach with anterior clinoidectomy provides the appropriate access for such endeavor. The link to the video can be found at: https://youtu.be/WtAP8uqSW0M.

Orbitopterional Approach for the Resection of a Suprasellar Craniopharyngioma: Adapting the Strategy to the Microsurgical and Pathologic Anatomy

Objectives To describe the orbitopterional approach for the resection of a suprasellar craniopharyngioma with emphasis on the microsurgical and pathological anatomy of such lesions. Design After completing the orbitopterional craniotomy in one piece including a supraorbital ridge osteotomy, the Sylvian fissure was split in a distal to proximal direction. The ipsilateral optic nerve and internal carotid artery were identified. Establishing a corridor to the tumor through both the opticocarotid and optic cisterns allowed for a wide angle of attack. Using both corridors, a microsurgical gross total resection was achieved. A radical resection required transection of the stalk at the level of the hypothalamus. Photographs of the region are borrowed from Dr Rhotons laboratory to illustrate the microsurgical anatomy. Understanding the cisternal and topographic relationships of the optic nerve, optic chiasm, and internal carotid artery is critical to achieving gross total resection while preserving normal anatomy. Participants The surgery was performed by the senior author assisted by Dr. Jaafar Basma. The video was edited by Dr. Vincent Nguyen. Outcome Measures Outcome was assessed with extent of resection and postoperative visual function. Results A gross total resection of the tumor was achieved. The patient had resolution of her bitemporal hemianopsia. She had diabetes insipidus with normal anterior pituitary function. Conclusions Understanding the microsurgical anatomy of the suprasellar region and the pathological anatomy of craniopharyngiomas is necessary to achieve a good resection of these tumors. The orbitopterional approach provides the appropriate access for such endeavor. The link to the video can be found at: https://youtu.be/Be6dtYIGqfs.

Pseudoaneurysm Surgery Simulation Using the “Live Cadaver” Model for Neurosurgical Education

Reduced number of working hours for residents and the trend toward minimal or even noninvasive treatment of cerebral aneurysms have resulted in residents’ decreased exposure to live surgery in the operating room. This decrease becomes increasingly relevant when surgeons encounter complications, especially vascular injuries and intraoperative rupture of aneurysms, after completion of their training, neurosurgery residents will face complicated cases and intraoperative aneurysmal rupture in their practice while they are on their own, and to develop competency in managing cerebral aneurysms, laboratory training will be the compensation mechanism to cover the decreased hands-on experience in the OR. In this chapter we will describe a more realistic aneurysm model, which allows repetitive training under lifelike conditions for residents and other trainees to practice surgical clipping of cerebral aneurysms.

Intraoperative Intratumoral Embolization of a Complex Recurrent Hemangiopericytoma: Technical Report and Review of the Literature.

Objective Recurrent brain tumors represent a challenge for neurosurgeons because of the extensive blood loss and the time needed for surgical resection. Only a few hemostatic agents are useful to prevent the bleeding and thus facilitate the surgical resection. Fibrin sealant can be used to achieve sealing, tissue adherence, or hemostasis when other means of hemostasis are inadequate or inappropriate. We report the feasibility and positive effects of direct intratumoral injection of fibrin sealant during resection of a recurrent hemangiopericytoma. Material and Methods The intraoperative intratumoral injection of fibrin sealant changed the tumor properties of a recurrent hemangiopericytoma of the tentorium with infra- and supratentorial extension. From a loose friable briskly bleeding tumor, this complex lesion became a nonbleeding well-demarcated soft-firm tumor that could easily be dissected off the pial surface and totally resected without extensive bleeding. Results There are several benefits of intratumoral injection of fibrin sealant in hemangiopericytomas: (1) the extensive bleeding is diminished and blood loss minimized; (2) the restriction of the surgical view by the venous oozing is diminished, making the microsurgical dissection of the tumor capsule off the pial surface easier and safer; (3) the loose consistency of the tumor becomes firmer and facilitates the manipulation of the tumor and leads to a safer resection; and (4) a shorter operating time is needed. Conclusion The use of intratumoral fibrin glue injection is a safe and useful technique that could be used for hemostasis of highly vascularized tumors to facilitate a safer resection and to reduce blood loss.