1/10. Anterior encephalocele with subcutaneous right facial nodule. Encephaloceles consist of heterotopic brain tissue that remains connected to the central nervous system. As such, these lesions can occur anywhere along the midline of the head, neck, and back. The clinical findings associated with an encephalocele are often cutaneous, prompting consultation with a dermatologist. Although abnormalities of the skin overlying the spinal cord are readily recognized by our specialty as markers for dysraphism, head and neck lesions may present a diagnostic challenge. We describe a case of an anterior encephalocele to increase awareness of this disorder and to emphasize the clinical findings that will assist with diagnosis. Our case is of particular interest because of the parasagittal location of the facial nodules and minimal actual midline involvement. ( info) |
2/10. Monomelic amyotrophy associated with the 7472insC mutation in the mtDNA tRNASer(UCN) gene. We describe a 49-year-old male patient who experienced progressive amyotrophy with no sensorial abnormality in the left arm since 45 years of age. The neuromuscular syndrome was identical to that known as Hirayama disease, a rare form of focal lower motor neuron disease affecting the C7-C8-T1 metamers of the spinal cord. Asymmetric neurosensorial hearing loss was present since age 35 in the patient, and was also documented in an elder sister and in the mother. A muscle biopsy showed cytochrome c oxidase (COX) negative fibers but no ragged-red fibers, and mild reduction of COX was confirmed biochemically. The patient was found to have high levels of a known pathogenic mutation of mtDNA, the 7472insC in the gene encoding the tRNA(Ser(UCN)). Investigation on several family members showed a correlation between mutation load and clinical severity. This is the second report documenting the association of lower motor neurone involvement with a specific mtDNA. ( info) |
3/10. Anterior inferior cerebellar artery infarct with unilateral deafness. We report the case of a young man with anterior inferior cerebellar artery infarct causing unilateral deafness. Clinical features and audiometry suggested cochlear localization for deafness. MRI brain showed an infarct in the right AICA territory with involvement of pons. Involvement of the internal auditory artery explains the cochlear deafness. ( info) |
4/10. Transient unilateral hearing loss induced by electrocortical stimulation. A 32-year-old patient with seizures experienced decreased right-ear hearing during electrocortical stimulation mapping of the left lateral superior temporal gyrus. Audiometric testing under headphones confirmed a reversible, moderate unilateral hearing loss. Under binaural listening conditions, auditory comprehension was impaired at the same site, whereas word repetition, environmental sound recognition, naming, and spontaneous speech remained intact. ( info) |
5/10. Increased amplitudes of distortion product otoacoustic emissions in patients with unilateral acoustic neuroma. We present a case series of 4 patients with a unilateral acoustic neuroma and increased amplitudes of the distortion products of otoacoustic emissions (DPOAEs) at the low- and middle- frequency bandwidth on the involved side compared to the uninvolved side despite a 28-dB hearing level (HL) worse (compared to the uninvolved side) pure-tone hearing threshold average for standard audiometric frequencies between 1 and 6 kHz at the involved side. In 3 of these patients, 2 with an inferior vestibular nerve origin of the acoustic neuroma and one in whom the nerve of origin could not be unequivocally defined, the tumor was extending extrameatally. One patient had a purely intrameatal acoustic neuroma of superior vestibular nerve origin. Moreover, notable was the presence of the DPOAEs in all of the involved ears despite elevated pure-tone hearing thresholds (pure- tone averages for the standard audiometric frequencies between 1 and 6 kHz ranging between 36 and 62 dB HL). ( info) |
6/10. Auditory and electrophysiological patterns of a unilateral lesion of the lateral lemniscus. Auditory disorders resulting from focal brainstem lesions are rarely symptomatic. Isolated lesions of the inferior colliculus have previously been reported, whereas no detailed description of a localized involvement of the lateral lemniscus is yet available. We report a unilateral lesion of the lateral lemniscus by a bleeding in a cavernoma. Symptoms included strictly contralateral tinnitus and auditory impairment, with normal pure-tone and speech audiometry. Conversely, the dichotic listening test revealed an extinction of contralateral ear input. The brainstem auditory evoked potentials disclosed a reduced and delayed wave V only after contralateral ear stimulation, while the middle latency evoked potentials were normal. This observation shows that a unilateral lesion of the lateral lemniscus can produce auditory symptoms. The dysfunction of auditory pathways is associated with specific electrophysiological abnormalities that can be assessed by evoked potential recording. ( info) |
7/10. Management of acoustic neuroma in the only hearing ear. patients with acoustic neuroma in their only hearing ear are not frequently seen in clinical practice. Managing this group of patients is a challenge to both the patient and surgeon. In this study we report on five cases of acoustic neuroma in an only hearing ear. Our decision for conservative management of those patients with regular follow-up using auditory brain stem response and magnetic resonance imaging is discussed. Other management options currently available are reviewed as well. ( info) |
8/10. Brainstem auditory evoked responses that disappear during sleep: a possible manifestation of a neurogenic vestibular evoked response. OBJECTIVE: To present a case of unilateral hearing loss in which a brainstem auditory evoked potential (BAEP) disappeared during sleep on the symptomatic side, and to argue that this may actually be a manifestation of a neurogenic vestibular evoked potential (NVESTEP). MATERIAL AND METHOD: Brainstem auditory evoked potentials were performed in the standard manner. RESULT: A poorly organized response was obtained during wakefulness on the symptomatic side that resembled a BAEP. The BAEP for the right ear was better organized. During sleep, the response for the left ear disappeared. CONCLUSIONS: The poor organization of the response of the left ear compared to the right, and its disappearance during sleep, suggests that the response for the left ear was actually an NVESTEP and not a BAEP. The possibility of recording vestibular responses with auditory stimuli may have important implications for BAEP examinations performed during wakefulness that may lead to false negative results, in neonatal screening for hearing loss that use tone stimuli, and also in brain mapping using magnetic resonance imaging (MRI) and positron emission tomography (PET) relating to the auditory cortex. ( info) |
9/10. Nonsyndromic isolated unilateral cochlear nerve aplasia without narrow internal auditorymeatus: a previously overlooked cause of unilateral profound deafness in childhood. OBJECTIVES: Juvenile or adolescent unilateral profound sensorineural deafness (worldwide prevalence, 0.1% to 0.2%) has been attributed to postnatal viral infection, sudden deafness, prenatal and perinatal problems including maternal rubella and viral infections, congenital innerear anomalies, and other factors. Herein, 2 cases are reported and another potentially important cause of unilateral profound hearing loss is proposed. methods: Two nonsyndromic cases of a presently "very rare" cause of pediatric unilateral deafness are presented as a retrospective case study. RESULTS: The 2 patients showed isolated aplasia of the cochlear nerve; other branches of the eighth cranial nerve, the seventh nerve, and the inner ear were spared,and there was no anomaly of the internal auditory meatus. Both functional and imaging studies confirmed the isolated lesion (absence) of the cochlear nerve. CONCLUSIONS: Because of the absence of bony abnormalities, such cases may have been overlooked. The authors would like to advocate this isolated anomaly of thecochlear nerve as an important cause of juvenile or adolescent unilateral profound deafness. ( info) |
10/10. Objective pulsatile tinnitus: a video clip demonstration of the condition. Pulsatile tinnitus is an uncommon condition. We describe a case of pulsatile tinnitus and visually demonstrate a pulsating tympanic membrane caused by a postoperative cerebrospinal leak into the mastoid air cells following resection of a left temporal petrous meningioma. To our knowledge, this is the first case in the literature where an objective pulsatile tinnitus has been captured on video (see www.laryngoscope.com). ( info) |