The Extra-Extended Translabyrinthine Approach for Resection of Large Acoustic Neuroma: 2-Dimensional Operative Video.

The extended translabyrinthine approach to acoustic neuroma (AN) was created to allow improved visualization and access to larger tumors.1,2 The dural opening, however, remained confined to the presigmoid space. Other authors have introduced modifications to increase the dura exposure around the internal auditory canal (IAC).3-5 The extra-extended translabyrinthine approach was conceptualized by the senior author (CC) to maximize AN exposure and early cranial nerve identification. The tentorial peeling was added to allow extradural mobilization of the temporal lobe.6 This allows further safe bone removal around the IAC and petrous apex and consistent opening of the facial canal at IAC fundus. This modification creates 280-to-360-degree dura exposure at the IAC. The dural opening extends to the petrous apex superiorly and the prepontine arachnoid cistern inferiorly and includes resection of a tentorium dural flap created by the tentorial peeling.6 This exposure allows for near circumferential exposure of the tumor and early identification of the glossopharyngeal nerve in the cochlear aqueduct area, the trigeminal nerve at the porus trigeminal, and the facial nerve (FN) at IAC fundus. In addition, this ample exposure permits identification of the FN trajectory in the tumor capsule before any tumor dissection. We present a detailed video of extra-extended translabyrinthine approach technique in a patient with a large left AN (Hannover classification T4B).7 This video does not involve any human research projects not requiring Institutional Review Board/ethic committee approval. The patient consented to the procedure and to the publication of his image. Complete resection was obtained. The FN function was House-Brackman I/VI.

Partial Labyrinth Removal Restricted to the Superior Semicircular Canal in Focal Combined Transpetrosal Approach: Description and Illustrative Cases.

BACKGROUND AND OBJECTIVES: The labyrinthine structures obstruct the surgical view of the deep petroclival region in the transpetrosal approach. Historically, labyrinthectomy and removal of all 3 semicircular canals, with resultant deafness, was used in patients with ipsilateral functional hearing deficits to improve access. The advent and systematization of superior and posterior semicircular canal removal (transcrusal approach) with good rates of hearing preservation has allowed a redefinition of the possibility of partial labyrinthectomy in patients without previous hearing deficits. The present manuscript is intended to describe a technical refinement of partial labyrinthectomy during focal combined petrosectomy, offering a customization of the approach through the selective removal of the superior semicircular canal for specific types of tumors. METHODS: The use of the technique is demonstrated through surgical drawings, pictures, and videos. The rationale to indicate this new approach is discussed based on clinical cases. RESULTS: Three illustrative clinical cases (petroclival meningiomas) are demonstrated. Functional hearing on the approach side has been preserved in all of them. CONCLUSION: The focal combined transpetrosal approach associated with the superior semicircular canal resection has been a promising surgical technique in the treatment of selected petroclival tumors. It has the potential to further decrease the risks of postoperative auditory and vestibular dysfunctions associated with labyrinthectomies.

Hearing preservation middle fossa approach for intracanalicular vestibular schwannoma in a NF2 patient.

Hearing preservation is a cornerstone in the management of intracanalicular vestibular schwannomas. This video demonstrates a middle fossa approach to an intracanalicular schwannoma and highlights some technical and anatomical nuances relevant to the procedure. The patient had sustained hearing preservation in the postoperative period. There are potential benefits in favor of the middle fossa when the tumor reaches the fundus of the internal auditory canal, but the surgeon's individual experience plays a decisive role in the choice of approach. The video can be found here: https://stream.cadmore.media/r10.3171/2021.7.FOCVID21121.

Tentorial Peeling: Surgical Extradural Navigation to Protect the Temporal Lobe in the Focused Combined Transpetrosal Approach.

BACKGROUND: Transpetrosal approaches have been used for treatment of tumors in the petroclival region for many years. Injury to the temporal lobe, however, has been a potential drawback of the techniques described to date. OBJECTIVE: To describe modifications of the transpetrosal surgical technique, which allows extradural manipulation of the temporal lobe during the focused combined transpetrosal approach. This extra layer of protection avoids mechanical brain retraction, direct trauma to the temporal lobe and disruption of the local venous structures. METHODS: The present manuscript describes an innovative technical nuance based on the combination of the focused combined transpetrosal approach, the peeling of the dural layers of the tentorium, and the reverse peeling of the middle fossa dura mater. Ample illustrative material is provided and illustrative cases are presented. CONCLUSION: Peeling of the dural layers of the tentorium is a promising modification of the transpetrosal approach to increase the safety of the temporal lobe manipulation.

Hearing preservation using the middle fossa approach for the treatment of vestibular schwannoma.

BACKGROUND: The incidence of small vestibular schwannomas in patients with serviceable hearing is increasing because of the widespread use of MRI. The middle fossa approach provides the patient with an opportunity for tumor removal with hearing preservation. OBJECTIVE: To determine the rate of hearing preservation and facial nerve outcomes after removal of a vestibular schwannoma with the use of the middle fossa approach. METHODS: A retrospective case review at a tertiary, academic medical center was performed identifying patients from 1998 through 2008 that underwent removal of a vestibular schwannoma by the middle fossa approach. Preoperative and postoperative audiograms were compared to determine hearing preservation rates. In addition, facial nerve outcomes at last follow-up were recorded. RESULTS: Forty-six patients underwent a middle fossa craniotomy for the removal of a vestibular schwannoma. Of the 38 patients that had class A or class B hearing preoperatively, 24 (63.2%) retained class A or B hearing and 29 (76.3%) retained class A, B, or C hearing. When tumors were 10 mm or less in patients with class A or B preoperative hearing, 22 of 30 patients (73.3%) retained class A or B hearing. When the tumor size was greater than 10 mm in patients with class A or B preoperative hearing, 2 of 8 patients (25%) retained class A or B hearing. At most recent follow-up, 76.1% of patients had House-Brackmann grade I facial function, 13.0% had House-Brackmann grade II facial function, and 10.9% had House-Brackmann grade III facial function. CONCLUSION: Hearing preservation rates are excellent using the middle fossa approach, especially for smaller tumors. No patient experienced long-term facial nerve function worse than House-Brackmann grade III.

Minimally invasive transfrontal sinus approach to resection of large tumors of the subfrontal skull base.

OBJECTIVES/HYPOTHESIS: To review our favorable experience with a minimally invasive transfrontal sinus approach to tumors of the subfrontal region. STUDY DESIGN: Retrospective review in a tertiary care referral practice. METHODS: Patients undergoing anterior skull base surgery by the senior author (Y.D.) were reviewed and transfrontal sinus approach patients selected for review. All cases of transfrontal sinus approaches to the base of the anterior cranial fossa from 2007 to 2011 were reviewed in a retrospective fashion. RESULTS: A total of 14 cases were noted. Male to female ratio was 10 to 4 with an average age of 58.2 years. The pathologies included: meningioma (n = 6), esthesioneuroblastoma (n = 3), squamous cell carcinoma (n = 3), adenocarcinoma (n = 1), and adenoid cystic carcinoma (n = 1). Five intradural and nine extradural dissections were performed. No major complications were noted, and no patients required conversion to a traditional transfacial approach or required the use of a craniotomy. Twelve patients underwent complete tumor removal, whereas two patients underwent subtotal tumor removal. Reasons for subtotal removal were not access related but rather tumor characteristic related (carotid artery wall involvement, optic chiasm involvement). Contraindication to this approach is the presence of a hypoplastic or aplastic frontal sinus. CONCLUSIONS: The minimally invasive transfrontal sinus approach to the subfrontal region provides ready expeditious access to the base of the anterior cranial fossa without the need for brain retraction, craniotomy or naso-orbital osteotomies. It represents an excellent alternative in the surgical access of both intra- and extradural tumors in this region of the skull base.

Endoscopic treatment of thalamic neuroepithelial cysts. Report of three cases.

Thalamic neuroepithelial cysts are rare lesions of the central nervous system. Surgical management of these lesions has varied and yielded mixed results. The authors identified 10 reported cases in the literature, five of which involved symptomatic lesions. The authors present three unique cases of symptomatic thalamic neuroepithelial cysts associated with hydrocephalus, which were all successfully treated using endoscopic third ventriculostomy and fenestration of the cyst into the third ventricle.

Bromocriptine-responsive akinetic mutism following endoscopy for ventricular neurocysticercosis. Case report and review of the literature.

A 26-year-old woman with obstructive hydrocephalus caused by a cysticercal cyst blocking the left foramen of Monro was initially treated with an external ventriculostomy and subsequent endoscopically assisted cyst resection and septostomy. Postoperatively, the patient developed the clinical syndrome of akinetic mutism, but her condition improved after the administration of the dopaminergic agonist bromocriptine. This result indicates that a disruption in the ascending dopaminergic pathway involved in behavior formation was likely the cause of these neurological symptoms.

Titanium cage reconstruction after cervical corpectomy.

OBJECT: The authors evaluated the efficacy of titanium cage- and anterior cervical plate (ACP)-augmented fusion for reconstruction following decompressive cervical corpectomy in nontraumatic disease. METHODS: Forty-five patients ranging from 37 to 77 years of age underwent anterior cervical corpectomy followed by titanium cage-assisted reconstruction in which the cages were filled with autologous bone obtained from the resected vertebral bodies (VBs). Plates were placed in all patients. Follow-up radiographic evaluation included computerized tomography scanning and plain flexion-extension radiography. Fusion was demonstrated in all but one patient without reconstruction-related complications. The single complication involved an endplate VB fracture with pistoning of the cage into the VB. The mean follow-up period was 12.9 months. CONCLUSIONS: Autologous corpectomy bone-filled titanium cages supplemented with ACPs are an effective means of reconstruction after compressive cervical corpectomy. This technique provides a reasonable alternative to procedures involving long solid strut grafts obtained from the bone bank or from the patient.

Craniotomia fronto-órbito-pterional unilateral e clinoidectomia anterior extradural no tratamento de aneurisma bilateral do segmento oftálmico da artéria carótida interna / Unilateral fronto-orbito-pterional approach with extradural anterior clinoidectomy in the treatment of bilateral ophtalmic segment aneurism

Os autores relatam um caso de aneurisma bilateral em espelho do segmento oftálmico da artéria carótida interna tratado com craniotomia fronto-órbito-pterional direita associada com clinoidectomia anterior extradural