Vertebrobasilar System Laterality and Idiopathic Sudden Sensorineural Hearing Loss.

INTRODUCTION: The etiology of idiopathic sudden sensorineural hearing loss (ISSNHL) remains elusive, with vascular compromise as a proposed cause. This study aimed to explore the correlation between the vertebrobasilar vascular system laterality (VBVSL) and ISSNHL laterality. METHODS: We conducted a retrospective analysis of consecutive patients diagnosed with ISSNHL from 2015 to 2020. The VBVSL pattern was established via magnetic resonance imaging scans by a neuroradiologist. ISSNHL occurring contralaterally to the basilar artery (BA) curvature or ipsilaterally to the dominant vertebral artery (VA) was designated as a "positive match," with all other scenarios classified as a "negative match." RESULTS: Our study included 191 ISSNHL patients (median age 57 years, 89 males, 93 right ears). The majority of patients did not exhibit a positive match between ISSNHL laterality and the sides of BA curvature or dominant VA (28.8% and 36.6% for BA and VA, respectively). Notably, VA-positive match patients were significantly older than VA-negative match patients (59 vs. 53 years, p = 0.043), with a similar trend observed in BA-positive match compared to BA-negative match (59 vs. 54.5 years, p = 0.057). However, there was no significant difference in any other clinical, audiometric, or outcome factors between the positive and negative match groups. CONCLUSION: The findings suggest no association between VBVSL and ISSNHL laterality. Furthermore, patients in the positive match group did not exhibit distinct clinical or audiometric features compared to those without a match.

Achieving negative resection margins in oral cavity cancer with masticator space involvement-Is it feasible? International collaborative study.

BACKGROUND: Masticator space involvement in oral cavity squamous cell carcinoma (OCSCC) is considered an unresectable disease. Nevertheless, achieving negative resection margins is feasible in limited masticatory space involvement. MATERIALS AND METHODS: A multi-institutional study on OCSCC patients with masticator space invasion who underwent surgical resection. Margin status was assessed according to anatomic tumor involvement of the inframandibular and supra-mandibular notch. RESULTS: One-hundred and thirty-two patients met the inclusion criteria. Then, 67 patients (50.8%) were diagnosed with a supra-notch tumor and 65 (49.2%) with an infra-notch disease. Negative margins were more common in the infra-notch group (43.3 vs. 23.1%, p = 0.014), and positive margins were more common in the supra-notch group (41.5 vs. 23.9%, p = 0.041). Multivariable analysis demonstrated that supra-notch tumors had an increased likelihood for involved resection margins (odds ratio = 2.46, p = 0.036). CONCLUSION: OCSCC patients with masticator space involvement are prone for positive surgical margins in tumors extending above the supra-mandibular notch.

Tegmen attenuation in patients with idiopathic intracranial hypertension is progressive.

OBJECTIVES: To prove that temporal bone tegmen attenuation in patients with idiopathic intracranial hypertension (IIH) is progressive. STUDY DESIGN: Retrospective blind study at a tertiary academic medical center. METHODS: Enrolled were medical records of patients with IIH that included at least two sequential computed tomography (CT) scans. The vertical distances between the floor of the middle fossa to the superior and lateral semicircular canals (SSC and LSC, respectively), to the scutum and minimal squama thickness were measured. The same measurements were made in scans of control subjects. The impact of demographics and metabolic variables including opening lumbar puncture (LP) pressure were evaluated. RESULTS: Twenty medical records were enrolled. Median age at diagnosis was 21 years; 16 were females. The median body mass index (BMI) was 32 kg/m2 . Initial LP pressure was 195 mm cerebrospinal fluid (CSF). The median time interval between CT scans was 58 months. A median attenuation of 0.35 mm and 0.25 mm over the right and left LSC and of 0.5 mm and 0.3 mm over the right and left scutum, was found, respectively. The thicknesses of the SSC and squama remained stable. No attenuation was present in controls. The opening pressure on initial LP (median 195 mm CSF), was positively correlated with the degree of tegmen attenuation, but the age at diagnosis and BMI were not. CONCLUSIONS: Tegmen attenuation may be progressive in patients with idiopathic increased intracranial pressure and correlated with the opening pressure on LP. Tegmen defects and CSF leak should be looked for in these patients. LEVEL OF EVIDENCE: 4 Laryngoscope, 2020.

Prevalence of temporal bone tegmen defects among patients with Marfan syndrome.

BACKGROUND: Marfan syndrome (MFS) is a genetic disorder affecting connective tissue. The composition of the dura can change. Consequently, lumbo-sacral dural herniations and cerebrospinal fluid (CSF) leaks are encountered, however, they have yet to been described in the temporal bone. AIMS/OBJECTIVES: To define the prevalence of temporal bone meningocele or encephalocele among patients with MFS. MATERIALS AND METHODS: Reviewed medical records of all adult patients, diagnosed with MFS, who were treated between 1993 and 2018 at a single academic referral institute. Head targeted CT scans were analyzed. The presence of an anterior or lateral skull base defect was recorded. RESULTS: One-hundred and one patients diagnosed with MFS were identified. Twelve of which had suitable CT scans and were enrolled in the study. The median age of patients with defects was 65 years (range 41-71). Five of the twelve patients (41.6%) had tegmen defect. Of the seven defects found, the median size of the defects was 3 mm (range 2-5 mm). All defects were in the temporal bone, none in the anterior skull base. CONCLUSIONS AND SIGNIFICANCE: The prevalence of radiological evidence of a temporal bone defect among patients with MFS is high. This is a new, important, and potentially life-threatening association with the syndrome.

The association between auditory nerve neurovascular conflict and sudden unilateral sensorineural hearing loss.

HYPOTHESIS: There may be an association between a neurovascular conflict (NVC) of the auditory nerve and unilateral sudden sensorineural hearing loss (SSNHL). BACKGROUND: Compression of cranial nerves by vascular structures can lead to significant symptomatology that may require surgical decompression. Notable examples are trigeminal neuralgia and hemifacial spasm. Magnetic resonance imaging (MRI) is part of the workup for SSNHL, and it may depict an NVC of the auditory nerve. Here we look into the association between this NVC and unilateral SSNHL. METHODS: A retrospective analysis was performed on all consecutive patients with unilateral SSNHL who underwent an MRI scan in our medical center. The data collected included age, gender, side and severity of hearing loss, and accompanying complaints. Each MRI scan was reviewed by a neuroradiologist who was unaware of hearing loss laterality. The presence, side, extent, and location of a potential NVC involving the auditory nerve were determined, and a correlation between radiological findings and auditory parameters was sought. RESULTS: Fifty-four patients (male-to-female ratio 26:28, age range 25-80 years) were enrolled into the study. Fourteen of them (25.9%) had normal MRI findings. Twenty-six patients had a unilateral NVC, and the pathology was ipsilateral to the side of hearing loss in only 12 of them (46.2%). Fourteen (25.9%) patients had MRI findings of bilateral NVCs. There was no significant correlation between the side of the SSNHL and any radiological findings (P = .314). CONCLUSION: The data presented herein support the conclusion that there is no association between CN8 NVC and unilateral SSNHL. LEVEL OF EVIDENCE: 2b.

Clinical Implications of the Association Between Temporal Bone Tegmen Defects and Superior Semicircular Canal Dehiscence.

OBJECTIVE: To discuss the clinical implications of the association between temporal bone tegmen dehiscence (TD) necessitating surgical correction and the adjacent dehiscent superior semicircular canal (SSCD). STUDY DESIGN: Retrospective. SETTING: Tertiary referral center. PATIENTS: Sixteen patients with idiopathic TD, with or without SSCD, requiring surgical correction. INTERVENTIONS: Corrective surgery for TD. High-resolution temporal bone-targeted computed tomography. MAIN OUTCOME MEASURES: The impact of the minimal distance between TD and SSCD or the arcuate eminence on the choice of surgical approach to TD. RESULTS: The patients' median age was 58 years and 5 were males. The median body mass index was 31.8 kg/m. The average distance from the TD and the SSC was 4.9 mm (range 2.1-14.2 mm). Three of the 14 patients who were operated via a temporal craniotomy to fix a cerebrospinal fluid-leaking TD required plugging of an asymptomatic SSCD due to its close proximity (3-5 mm) to the defect, and two of them had relatively protracted vestibular recuperation. Two patients were operated via a transmastoid approach for sealing a cerebrospinal fluid-leaking TD coexisting with a bilateral asymptomatic SSCD. No patient had a hearing loss. CONCLUSION: The close proximity of a TD and an SSCD might not allow selective exposure. As a result, asymptomatic SSCD may become symptomatic during TD correction via the temporal craniotomy approach. The need to plug an asymptomatic SSCD that is proximal to a TD should be factored in planning for surgery and rehabilitation. The choice of surgical approach (middle fossa vs. transmastoid) could be influenced by this relationship, especially in cases of bilateral lesions.