Intralabyrinthine neurinoma: Management, exeresis and auditory restoration with cochlear implant.

BACKGROUND AND OBJECTIVE: Vestibular schwannoma is a benign tumour that originates in the eighth cranial nerve. It is termed intralabyrinthine schwannoma (ILS) when it develops in the inner ear, this being a rare origin. We present our experience in the management of three patients with ILS. MATERIALS AND METHODS: The results of tumour excision and cochlear implantation were evaluated in three patients with ILS: two intracochlear schwannomas (ICS) and one intravestibular schwannoma (IVS). RESULTS: Prior to surgery, all patients presented progressive sensorineural hearing loss and tinnitus. Complete tumour resection and cochlear implantation was possible in all patients, with favourable hearing rehabilitation. CONCLUSIONS: The therapeutic approach will depend on tumour size, growth rate, degree of hearing loss and presence of vestibular symptoms. Cochlear implantation (CI) in patients with ILS is possible when the cochlear nerve is present and functional. CI in patients, whether or not preceded by tumour excision, is an option with good hearing results in selected patients.

Malformation of the eighth cranial nerve in children. / Malformaciones del octavo par en niños.

INTRODUCTION AND OBJECTIVES: Prevalence of congenital sensorineural hearing loss (SNHL) is approximately 1.5-6 in every 1,000 newborns. Dysfunction of the auditory nerve (auditory neuropathy) may be involved in up to 1%-10% of cases; hearing losses because of vestibulocochlear nerve (VCN) aplasia are less frequent. The objectives of this study were to describe clinical manifestations, hearing thresholds and aetiology of children with SNHL and VCN aplasia. METHODOLOGY: We present 34 children (mean age 20 months) with auditory nerve malformation and profound HL taken from a sample of 385 children implanted in a 10-year period. We studied demographic characteristics, hearing, genetics, risk factors and associated malformations (Casselman's and Sennaroglu's classifications). Data were processed using a bivariate descriptive statistical analysis (P<.05). RESULTS: Of all the cases, 58.8% were bilateral (IIa/IIa and I/I were the most common). Of the unilateral cases, IIb was the most frequent. Auditory screening showed a sensitivity of 77.4%. A relationship among bilateral cases and systemic pathology was observed. We found a statistically significant difference when comparing hearing loss impairment and patients with different types of aplasia as defined by Casselman's classification. Computed tomography (CT) scan yielded a sensitivity of 46.3% and a specificity of 85.7%. However, magnetic resonance imaging (MRI) was the most sensitive imaging test. CONCLUSIONS: Ten percent of the children in a cochlear implant study had aplasia or hypoplasia of the auditory nerve. The degree of auditory loss was directly related to the different types of aplasia (Casselman's classification) Although CT scan and MRI are complementary, the MRI is the test of choice for detecting auditory nerve malformation.

The role of diffusion-weighted magnetic resonance imaging in cholesteatoma diagnosis and follow-up. Study with the diffusion PROPELLER technique.

INTRODUCTION AND OBJECTIVES: The diagnosis of cholesteatoma is based on clinical evaluation and computed tomography. New non-echo-planar diffusion-weighted magnetic resonance imaging (MRI) techniques, without intravenous contrast, are capable of differentiating cholesteatoma from inflammatory tissue, cholesterol granuloma and granulation tissues. The technique is very helpful in differential diagnosis of cholesteatoma, mainly after canal wall-up tympanoplasty surgery, to avoid routine second-look surgery in these patients. Congenital cholesteatoma and difficult cases can be detected and correctly diagnosed as well. The aim of this study was to evaluate sensitivity, specificity, positive predictive value and negative predictive value of the diffusion-weighted PROPELLER MRI in cholesteatoma diagnosis. METHODS: A prospective study was performed on 52 patients. Clinical and surgical findings were correlated with diffusion-weighted PROPELLER MRI results. RESULTS: Sensitivity, specificity and positive and negative predictive values were 92.85%, 92.30, 92.85 and 92.30%, respectively. CONCLUSIONS: Diffusion-weighted PROPELLER imaging is an effective technique in cholesteatoma diagnosis. It is capable of detecting lesions larger than 2mm.