An aural myiasis case in a 54-year-old male farmer in Korea.
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A 54-year-old male farmer residing in Chunchon, Korea, complaining of blood tinged discharge and tinnitus in the left ear for two days, was examined in August 16, 1996. Otoscopic examination revealed live maggots from the ear canal. The patient did not complain of any symptoms after removal of maggots. Five maggots recovered were identified as the third stage larvae of Lucilia sericata (Diptera: Calliphoridae). This is the first record of aural myiasis in Korea. (+info)
Isolated metastases of adenocarcinoma in the bilateral internal auditory meatuses mimicking neurofibromatosis type 2--case report.
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A 56-year-old male with a history of lung cancer presented with isolated metastases of adenocarcinoma in the bilateral internal auditory meatuses (IAMs), mimicking the bilateral acoustic schwannomas of neurofibromatosis type 2, and manifesting as rapidly worsening tinnitus and bilateral hearing loss. Magnetic resonance imaging showed small tumors in both IAMs with no sign of leptomeningeal metastasis. The preoperative diagnosis was neurofibromatosis type 2. Both tumors were removed and the histological diagnoses were adenocarcinoma. Neuroimaging differentiation of a solitary metastatic IAM tumor from a benign tumor is difficult, although rapidly progressive eighth cranial nerve dysfunction suggests a malignant process. Metastases should be considered as a rare diagnostic possibility in a patient with small tumors in both IAMs. (+info)
Thalamocortical dysrhythmia: A neurological and neuropsychiatric syndrome characterized by magnetoencephalography.
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Spontaneous magnetoencephalographic activity was recorded in awake, healthy human controls and in patients suffering from neurogenic pain, tinnitus, Parkinson's disease, or depression. Compared with controls, patients showed increased low-frequency theta rhythmicity, in conjunction with a widespread and marked increase of coherence among high- and low-frequency oscillations. These data indicate the presence of a thalamocortical dysrhythmia, which we propose is responsible for all the above mentioned conditions. This coherent theta activity, the result of a resonant interaction between thalamus and cortex, is due to the generation of low-threshold calcium spike bursts by thalamic cells. The presence of these bursts is directly related to thalamic cell hyperpolarization, brought about by either excess inhibition or disfacilitation. The emergence of positive clinical symptoms is viewed as resulting from ectopic gamma-band activation, which we refer to as the "edge effect." This effect is observable as increased coherence between low- and high-frequency oscillations, probably resulting from inhibitory asymmetry between high- and low-frequency thalamocortical modules at the cortical level. (+info)
Lateralized tinnitus studied with functional magnetic resonance imaging: abnormal inferior colliculus activation.
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Tinnitus, the perception of sound in the absence of external stimuli, is a common and often disturbing symptom that is not understood physiologically. This paper presents an approach for using functional magnetic resonance imaging (fMRI) to investigate the physiology of tinnitus and demonstrates that the approach is effective in revealing tinnitus-related abnormalities in brain function. Our approach as applied here included 1) using a masking noise stimulus to change tinnitus loudness and examining the inferior colliculus (IC) for corresponding changes in activity, 2) separately considering subpopulations with particular tinnitus characteristics, in this case tinnitus lateralized to one ear, 3) controlling for intersubject differences in hearing loss by considering only subjects with normal or near-normal audiograms, and 4) tailoring the experimental design to the characteristics of the tinnitus subpopulation under study. For lateralized tinnitus subjects, we hypothesized that sound-evoked activation would be abnormally asymmetric because of the asymmetry of the tinnitus percept. This was tested using two reference groups for comparison: nontinnitus subjects and nonlateralized tinnitus subjects. Binaural noise produced abnormally asymmetric IC activation in every lateralized tinnitus subject (n = 4). In reference subjects (n = 9), activation (i.e., percent change in image signal) in the right versus left IC did not differ significantly. Compared with reference subjects, lateralized tinnitus subjects showed abnormally low percent signal change in the IC contralateral, but not ipsilateral, to the tinnitus percept. Consequently, activation asymmetry (i.e., the ratio of percent signal change in the IC ipsilateral versus contralateral to the tinnitus percept) was significantly greater in lateralized tinnitus subjects as compared with reference subjects. Monaural noise also produced abnormally asymmetric IC activation in lateralized tinnitus subjects. Two possible models are presented to explain why IC activation was abnormally low contralateral to the tinnitus percept in lateralized tinnitus subjects. Both assume that the percept is associated with abnormally high ("tinnitus-related") neural activity in the contralateral IC. Additionally, they assume that either 1) additional activity evoked by sound was limited by saturation or 2) sound stimulation reduced the level of tinnitus-related activity as it reduced the loudness of (i.e., masked) the tinnitus percept. In summary, this work demonstrates that fMRI can provide objective measures of lateralized tinnitus and tinnitus-related activation can be interpreted at a neural level. (+info)
A comparison of betahistine hydrochloride with placebo for vertebral-basilar insufficiency: a double-blind study.
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To test the effectiveness of betahistine HC1 in reducing the frequency of transient ischemic attacks (TIAs) caused by vertebral-basilar artery insufficiency, we randomly assigned 26 patients with a typical history of the condition to a placebo-drug or a drug-placebo sequence, each sequence lasting two months. During the study, the frequency of TIAs did not differ significantly between the placebo and the drug groups. Subjective responses indicated some value for betahistine as a palliative agent. (+info)
Effectiveness of Ginkgo biloba in treating tinnitus: double blind, placebo controlled trial.
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OBJECTIVE: To determine whether Ginkgo biloba is effective in treating tinnitus. DESIGN: Double blind, placebo controlled trial using postal questionnaires. PARTICIPANTS: 1121 healthy people aged between 18 and 70 years with tinnitus that was comparatively stable; 978 participants were matched (489 pairs). INTERVENTION: 12 weeks' treatment with either 50 mg Ginkgo biloba extract LI 1370 three times daily or placebo. MAIN OUTCOME MEASURES: Participants' assessment of tinnitus before, during, and after treatment. Questionnaires included items assessing perception of how loud and how troublesome tinnitus was. Changes in loudness were rated on a six point scale. Changes in how troublesome were rated on a five point scale. RESULTS: There were no significant differences in primary or secondary outcome measures between the groups. 34 of 360 participants receiving active treatment reported that their tinnitus was less troublesome after 12 weeks of treatment compared with 35 of 360 participants who took placebo. CONCLUSIONS: 50 mg Ginkgo biloba extract LI 1370 given 3 times daily for 12 weeks is no more effective than placebo in treating tinnitus. (+info)
Ototoxicity associated with use of nucleoside analog reverse transcriptase inhibitors: a report of 3 possible cases and review of the literature.
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Although a variety of adverse effects have been attributed to treatment with nucleoside analog reverse transcriptase inhibitors (NRTIs) for human immunodeficiency virus type 1 (HIV-1) infection, only 5 cases of ototoxicity have been reported in the literature. We describe 3 additional cases of possible NRTI-associated ototoxicity in HIV-1-infected patients, all of whom were aged >45 years, had a history of noise-induced hearing loss, and reported tinnitus and deterioration in hearing in the setting of antiretroviral therapy. Reductions in mitochondrial DNA content induced by NRTIs, as well as mitochondrial DNA mutations associated with aging and HIV-1 infection, all may contribute to auditory dysfunction in older patients with HIV-1 infection. Prospective studies are necessary to determine the incidence of tinnitus and hearing loss among HIV-1-infected patients and their relationship to the use of NRTIs. (+info)
Symptomatic unruptured capillary telangiectasia of the brain stem: report of three cases and review of the literature.
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Three young patients with transient or intermittent focal neurological signs suggesting brain stem involvement are described, in whom high field MRI showed focal areas of hyperintensity in T2 weighted spin echo images, hypointensity in T2* weighted gradient echo images, and enhancement in postcontrast T1 weighted images consistent with unruptured capillary telangiectasia of the brain stem. The first patient was a 28 year old woman who complained of recurrent left ear tinnitus, exacerbated during the menstrual period; MRI demonstrated that the vascular anomaly involved the left acoustic pathway. The second patient was a 30 year old woman who had three episodes of paroxysmal left lip movement 4 weeks after child delivery; MRI showed capillary telangiectasia in the right corticonuclear pathway. The third patient, a 36 year old man, had a transient right Bell's palsy; MRI disclosed two circumscribed areas consistent with capillary telangiectasia in the left corticospinal tract and medial longitudinal fasciculus. Steroid receptors in the telangiectatic vessels walls might account for the recurrent and transient course seen in our two female patients. Awareness of the MRI features of capillary telangiectasia may help in defining the real incidence, clinical correlation, and the risk of haemorrhagic complications of these vascular malformations. (+info)