BACKGROUND AND OBJECTIVES: Measuring the eye movements including nystagmus is an essential step in the evaluation of dizzy patients. Therefore, it is necessary to observe and record the eye movements in animal for better understanding of human vestibular function. In this study, we investigated spontaneous, positional, positioning (Dix-Hallpike), post head shaking nystagmus in normal cats. MATERIALS AND METHODS: In ten normal cats, we measured the eye movements in vertical, horizontal and torsional planes using magnetic search coils with eyes open (EO), and eyes open in darkness (EOD). The eye movements were recorded with the head in neutral, tilted, hanging, and Dix-Hallpike positions as well as after head-shaking. RESULTS: 1) Positional nystagmus was present in 3 cats on the head hanging position. 2) Among the three cats which had positional nystagmus, one cat also had positioning nystagmus on Dix-Hallpike maneuver. 3) On repeated positional stimulations, the latency of nystagmus was increased and the duration and the slow phase velocity were decreased. 4) In the follow-up experiment after one month, the positional nystagmus was induced in the two same cats. 5) Spontaneous and post head shaking nystagmus were not present in any of the ten cats.
Animals ; Cats* ; Darkness ; Eye Movements ; Follow-Up Studies ; Head* ; Humans ; Nystagmus, Physiologic

To evaluate the immunological role in the etiopathogenesis of sudden deafness, sera from 44 patients with sudden sensorineural hearing loss were analyzed by 1) immunologic screening tests such as erythrocyte sedimentation rate(ESR), C-reactive protein(CRP), immunoglobulin(IgG, IgM) levels, complement(C3, C4) levels, autoantibody(rheumatoid factor, anti-DNA antibody, antinuclear antibody) levels, cryoglobulin and FTA-ABS 2) Western blotting immunoassay against cow's inner ear proteins 3) viral marker assay(serum IgG and IgM titer against cytomegalovirus, herpes simplex virus, varicella-zoster virus, measles virus, mumps virus and rubella virus). Thirteen(29.5%) of 44 patients displayed positive responses on immunologic screening tests. Significantly higher incidences of immunological abnormalities were found in the parameters such as levels of IgG, ESR, IgM and anti-nuclear antibody. Of 41 patients whose sera were analyzed by Western blot against fresh bovine inner ear antigen preparation, nobody showed the antibody against 68kD protein, and 1(2.4%), 4(9.8%), and 4(9.8%) had antibody which reacted with 60kD, 50kD and 33-35kD protein. On viral marker assay, 8(44.4%) of 18 patients showed positive IgG titers against herpes simplex virus, cytomegalovirus, varicella-zoster virus, measles virus, mumps virus and rubella virus. But any of 10 patients did not show significant IgM titers against those viruses. Statistical analysis revealed a significant correlation between the results of immunologic screening tests and the age of the patients(p<0.05 by chi-square), but no correlations with other clinical parameters such as sex, bilaterality, initial hearing level, and recovery(p>0.05 by chi-square respectively). There was no correlation between the results of viral marker assay(IgG) and recovery(p>0.05 by chi-square). The results suggest that viral infection may play a role in development and progress of sudden deafness, while the immunologic disorder may not affect the etiopathogenesis of sudden deafness.
Antibodies, Antinuclear ; Biomarkers ; Blood Sedimentation ; Blotting, Western ; Cytomegalovirus ; Ear, Inner ; Hearing ; Hearing Loss, Sensorineural ; Hearing Loss, Sudden* ; Herpesvirus 3, Human ; Humans ; Immune System* ; Immunoassay ; Immunoglobulin G ; Immunoglobulin M ; Incidence ; Mass Screening ; Measles virus ; Mumps virus ; Rubella ; Rubella virus ; Simplexvirus