Temporal Lobe Retraction Provides Better Surgical Exposure of the Peri-Geniculate Ganglion for Facial Nerve Decompression via Transmastoid Approach

PURPOSE: For the exposure of the labyrinthine segment of the facial nerve, transmastoid approach is not usually considered due to being situated behind the superior semicircular canal. To obtain a better view and bigger field for manipulation in the peri-geniculate area during facial nerve decompression, retraction of temporal lobe after bony removal of tegmen mastoideum was designed via transmastoid approach. MATERIALS AND METHODS: Fifteen patients with traumatic facial paralysis [House-Brackmann (HB) grade IV–VI], 3 patients with Bell's palsy (HB grade V–VI), and 2 patients with herpes zoster oticus (HB grade V–VI) underwent facial nerve decompression surgery between January 2008 and July 2014. In all patients, we performed temporal lobe retraction for facial nerve decompression via the transmastoid approach. Patients were examined using pre operative tests including high-resolution computed tomography, temporal magnetic resonance imaging, audiometry, and electroneurography (degenerative ratio >90%). Facial function was evaluated by HB grading scale before and 6 months after the surgery. RESULTS: After the surgery, facial function recovered to HB grade I in 9 patients and to grade II in 11 patients. No problems due to surgical retraction of the temporal lobe were noted. Compared to the standard transmastoid approach, our method helped achieve a wider surgical view for improved manipulation in the peri-geniculate ganglion in all cases. CONCLUSION: Facial nerve decompression via the transmastoid approach with temporal lobe retraction provides better exposure to the key areas around the geniculate ganglion without complications.

Temporal Lobe Retraction Provides Better Surgical Exposure of the Peri-Geniculate Ganglion for Facial Nerve Decompression via Transmastoid Approach

PURPOSE: For the exposure of the labyrinthine segment of the facial nerve, transmastoid approach is not usually considered due to being situated behind the superior semicircular canal. To obtain a better view and bigger field for manipulation in the peri-geniculate area during facial nerve decompression, retraction of temporal lobe after bony removal of tegmen mastoideum was designed via transmastoid approach. MATERIALS AND METHODS: Fifteen patients with traumatic facial paralysis [House-Brackmann (HB) grade IV–VI], 3 patients with Bell's palsy (HB grade V–VI), and 2 patients with herpes zoster oticus (HB grade V–VI) underwent facial nerve decompression surgery between January 2008 and July 2014. In all patients, we performed temporal lobe retraction for facial nerve decompression via the transmastoid approach. Patients were examined using pre operative tests including high-resolution computed tomography, temporal magnetic resonance imaging, audiometry, and electroneurography (degenerative ratio >90%). Facial function was evaluated by HB grading scale before and 6 months after the surgery. RESULTS: After the surgery, facial function recovered to HB grade I in 9 patients and to grade II in 11 patients. No problems due to surgical retraction of the temporal lobe were noted. Compared to the standard transmastoid approach, our method helped achieve a wider surgical view for improved manipulation in the peri-geniculate ganglion in all cases. CONCLUSION: Facial nerve decompression via the transmastoid approach with temporal lobe retraction provides better exposure to the key areas around the geniculate ganglion without complications.

How to Avoid Facial Nerve Injury in Mastoidectomy?

Unexpected iatrogenic facial nerve paralysis not only affects facial disfiguration, but also imposes a devastating effect on the social, psychological, and economic aspects of an affected person's life at once. The aims of this study were to postulate where surgeons had mistakenly drilled or where obscured by granulations or by fibrous bands and to look for surgical approach with focused on the safety of facial nerve in mastoid surgery. We had found 14 cases of iatrogenic facial nerve injury (IFNI) during mastoid surgery for 5 years in Korea. The medical records of all the patients were obtained and analyzed injured site of facial nerve segment with surgical technique of mastoidectomy. Eleven patients underwent facial nerve exploration and three patients had conservative management. 43% (6 cases) of iatrogenic facial nerve injuries had occurred in tympanic segment, 28.5% (4 cases) of injuries in second genu combined with tympanic segment, and 28.5% (4 cases) of injuries in mastoid segment. Surgeons should try to identify the facial nerve using available landmarks and be kept in mind the anomalies of the facial nerve. With use of intraoperative facial nerve monitoring, the avoidance of in order to avoid IFNI would be possible in more cases. Many authors emphasized the importance of intraoperative facial nerve monitoring, even in primary otologic surgery. However, anatomical understanding of intratemporal landmarks with meticulous dissection could not be emphasized as possible to prevent IFNI.

Cochlear Implantation for Profound Hearing Loss After Multimodal Treatment for Neuroblastoma in Children

OBJECTIVES: Neuroblastoma (NBL) predominantly affects children under 5 years of age. Through multimodal therapy, including chemotherapy, radiotherapy, surgery, and peripheral blood stem cell transplantation, the survival rate in patients with NBL have improved while treatment-related complications have also increased. Treatment-related ototoxicity, mainly from cisplatin, can result in profound hearing loss requiring cochlear implantation (CI). We analyzed the effectiveness and hearing preservation of CI recipients who had treated with multimodal therapy due to NBL. METHODS: Patients who received multimodal therapy for NBL and subsequent CIs were enrolled. A detailed review of the perioperative hearing test, speech evaluation, and posttreatment complications was conducted. Speech performance was analyzed using the category of auditory performance (CAP) score and the postoperative hearing preservation of low frequencies was also compared. Patients who were candidates for electro-acoustic stimulation (EAS) used an EAS electrode for low frequency hearing preservation. RESULTS: Three patients were identified and all patients showed improvement of speech performance after CI. The average of CAP score improved from 4.3 preoperatively to 5.8 at 1 year postoperatively. Two patients who were fitted with the Flex electrode showed complete hearing preservation and the preserved hearing was maintained over 1 year. The one remaining patient was given the standard CI-512 electrode and showed partial hearing preservation. CONCLUSION: Patients with profound hearing loss resulting from NBL multimodal therapy can be good candidates for CI, especially for EAS. A soft surgical technique as well as a specifically designed electrode should be applied to this specific population during the CI operation in order to preserve residual hearing and achieve better outcomes.

A Case of Herpes Zoster Oticus Involving Vestibular Nerve without Facial Nerve Palsy

Herpes zoster oticus (Ramsay Hunt syndrome) is characterized by facial nerve paralysis associated with vesticular eruptions and cochleovestibular symptoms. Many evidences have supported that it is caused by the reactivation of latent varicella-zoster virus in the geniculate ganglion. Recently we experienced a case 49-year-old man presented severe vertigo and a vesicular eruptions of auricle and external ear canal. It is an unusual variant of herpes zoster oticus that involves only vestibular nerve without facial nerve palsy and hearing loss. We believe this case results from reactivation of latent varicella zoster virus in the vestibular ganglion and report with a review of literatures.