Decompression Of Internal Auditory Canal Research Articles

Vestibular Nerve Section via Middle Cranial Fossa Approach.

Vestibular nerve section (VNS) is a surgical intervention with hearing preservation used for the treatment of Menière's disease after conservative medical therapy has failed (1,2). With the recent rise in less invasive treatments such as intratympanic gentamicin, VNS has been performed less frequently (3). The middle cranial fossa (MCF) approach for VNS is an uncommon approach due to its technical difficulty. However, it can provide the best distinction of internal auditory canal contents compared with retrosigmoid and retrolabyrinthine approaches. Several advancements in the MCF approach have been described, including the use of intraoperative facial nerve monitoring with electromyography, early removal of the temporal lobe retractor, and the use of an ultrasonic bone aspirator for internal auditory canal decompression (4-6). We demonstrate a case study with a step-by-step approach to successfully sectioning the superior and inferior vestibular nerves while utilizing these advancements and avoiding facial and cochlear nerve injury via the MCF (7). SDC video link: http://links.lww.com/MAO/B409.

Hearing preservation/rehabilitation surgery for small vestibular schwannoma: preliminary experience with the presigmoid retrolabyrinthine approach

Background The presigmoid retrolabyrinthine approach (PRA) for small vestibular schwannoma (VS) has unique advantages. Combination with partial labyrinthectomy further makes up its defect of high demand for anatomy. Objective Aimed to describe our use of the PRA with partial labyrinthectomy in VS surgery. Methods We retrospectively analyzed 10 patients diagnosed with VS who underwent PRA between September 2017 and November 2020. Their perioperative data were analyzed. Results Six tumors were on the left and three were on the right. One case was due to neurofibromatosis type 2 with bilateral involvement and underwent internal auditory canal decompression by PRA without tumor removal; all other patients underwent total tumor resection. Four patients underwent cochlear implantation simultaneously because of hearing loss that was detected during surgery. Three patients underwent partial labyrinthectomy. Five patients achieved hearing preservation, and one experienced hearing improvement. One of the three patients who underwent partial labyrinthectomy maintained hearing. All patients’ pre- and postoperative facial nerve functions were House-Brackmann grade I. After a median follow-up time of 13 months, no tumors recurred. Conclusions PRA for small VS is a safe and effective surgery that can achieve facial nerve and hearing preservation. Combination with partial labyrinthectomy can also preserve hearing.

Beyond Tympanomastoidectomy: A Review of Less Common Postoperative Temporal Bone CT Findings.

Postoperative temporal bone imaging after surgical procedures such as ossiculoplasty, tympanomastoidectomy, cochlear implantation, and vestibular schwannoma resection is often encountered in clinical neuroradiology practice. Less common otologic procedures can present diagnostic dilemmas, particularly if access to prior operative reports is not possible. Lack of familiarity with the less common surgical procedures and expected postoperative changes may render radiologic interpretation challenging. This review illustrates key imaging findings after surgery for Ménière disease, superior semicircular canal dehiscence, temporal encephalocele repairs, internal auditory canal decompression, active middle ear implants, jugular bulb and sigmoid sinus dehiscence repair, and petrous apicectomy.

Hearing Response Following Internal Auditory Canal Decompression in Neurofibromatosis Type 2.

Hearing response following an osteodural decompression of the internal auditory canal (IAC) is controversial. To evaluate the course of auditory brainstem responses (ABRs) and the early hearing response during the first year following IAC decompression for small to medium-sized vestibular schwannomas occurring in neurofibromatosis type 2 (NF2). Retrospective chart review of middle fossa craniotomy for IAC osteodural decompression in NF2-related vestibular schwannomas. Twelve NF2 patients were operated on from 2011 to 2016 for IAC decompression. All had NF2 according to the Manchester criteria. All had a progressive change of their ABRs documented from the diagnosis of NF2 over a mean period of 6.25 [0.36;10.9] yr. Treatment was proposed to stop hearing progression based on the speech discrimination scores (SDSs; n=4) or for hearing maintenance (n=8). In patients with prior hearing progression, hearing responses were observed in 3 of the 4 patients during the first year. One patient kept on progressing. In the hearing maintenance group, the SDSs remained stable. SDSs improved from 85% [20-100] to 92.5% [60-100] on average (n=12) and from 55% [20-80] to 77.5% [50-100] in the hearing progression group (n=4). ABRs improved in 4 patients following decompression. IAC decompression allows early objective hearing responses in select patients. We suggest that the procedure should be offered to patients with hearing progression based on their SDSs and/or associated progressive increases in their wave III and V latencies on ABRs.

Internal Auditory Canal Decompression for Hearing Maintenance in Neurofibromatosis Type 2 Patients.

In neurofibromatosis type 2 (NF2), multiple therapeutic options are available to prevent bilateral hearing loss that significantly affects the quality of life of patients. To evaluate the morbidity and functional results of internal auditory canal (IAC) decompression in NF2 patients with an only hearing ear. Twenty-one NF2 patients operated on for IAC decompression in a 3-year period with a minimum follow-up of 1 year were included in this retrospective study. They presented unilateral deafness due to previous contralateral vestibular schwannoma removal in 16 patients or contralateral hearing loss due to the tumor in 5 patients. Hearing level was of class A (American Academy of Otolaryngology-Head and Neck Surgery classification) in 7 patients, B in 8 patients, C in 1 patient, and D in 5 patients. Pure-tone average and speech discrimination score evaluations were performed at 6 days, 1 year, and during the follow-up. Eight patients had postoperative chemotherapy. No case of facial nerve palsy was observed. In the early postoperative period; all patients maintained the hearing class of the preoperative period. At 1-year follow-up, all but 3 patients maintained their hearing scores; at last follow-up (mean follow-up, 23 ± 8 months; range, 12-44 months), hearing classes remained stable with only 1 patient worsening from class B to C and 1 patient improving from class D to B. Decompression of IAC seems to be a useful procedure for hearing maintenance in NF2 patients, with very low morbidity. Ideal timing and association with chemotherapy should be evaluated in the future. FN, facial nerveIAC, internal auditory canalNF2, neurofibromatosis type 2PTA, pure tone averageSDS, speech discrimination scoreVS, vestibular schwannoma.

Functional Results of Internal Auditory Canal Decompression in NF2 Patients

Functional Results of Internal Auditory Canal Decompression in NF2 Patients

Internal Auditory Canal Decompression for the Control of Vertigo and Hearing Loss in Osteopetrosis

Internal Auditory Canal Decompression for the Control of Vertigo and Hearing Loss in Osteopetrosis