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Analysis of Clinical Features in Patients Showing Bilateral Vestibulopathy with Vestibular Function Test
Dong Hyun Kim, Jeong Hyun Lee, Bong Jik Kim, Chung Ku Rhee, Jae Yun Jung
Res Vestib Sci. 2014;13(2):47-52.
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Background and Objectives: Caloric test and rotatory chair test have been adopted in diagnosing bilateral vestibulopathy. However, most of patients who were confirmed by the diagnostic testing not complained typical symptoms of bilateral vestibulopathy such as ossilopsia and ataxia. Patients who do not have typical symptoms of bilateral vestibulopathy, were often diagnosed with bilateral vestibulopathy by caloric test and slow harmonic acceleration test (SHA). The aim of this study is to assess the clinical features between groups classified according to the caloric test and SHA test, and possibly to investigate the representative test in the diagnosis of bilateral vestibulopathy. Materials and Methods: Seventy-five patients were divided into three groups: (A) patients diagnosed with the caloric test only, (B) patients diagnosed with SHA test only, (C) patients satisfying the diagnostic criteria of both tests. Clinical characteristics, the results of physical examination, hearing test and vestibular function test (VFT) were compared among three groups. Results: There was no difference in clinical characteristics and results of physical examination among three groups. Regarding VFT results, only in step velocity test, The proportion of patients who showed low gain value on both sides were higher in group C than that of group A and B. No difference was observed in the other VFT results among three groups. Conclusion: We could not predict the clinical features of bilateral vestibulopathy by the results of VFT, and could not find preferable test in diagnosing bilateral vestibulopathy.
Results of High-Frequency and High-Acceleration Rotary Chair Test in Patients with Acute Unilateral Vestibular Neuritis
Hwan Seo Lee, Jun Woo Park, Chang Wook Lee, Chan Il Song, Myung Hoon Yoo, Hong Ju Park
Res Vestib Sci. 2014;13(2):41-46.
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  • 38 Download
AbstractAbstract PDF
r neuritis. Materials and Methods: Twenty-four patients who were diagnosed as acute vestibular neuritis and underwent rotational chair and caloric tests during March 2012 to March 2013 were included. Slow harmonic acceleration (SHA) test was performed at 0.01, 0.04, 0.16, 0.64, 1.28, and 2.00 Hz. Step velocity tests at the peak velocity of 100o/sec (low-acceleration) and 240o/sec (high-acceleration) were performed. Gains and phases in SHA test and gains and time constants (Tc) in step velocity test were analyzed. Results: In SHA test, decreased gain and phase lead was observed mostly in low frequencies. Gains (phases) at 0.01, 0.04, 0.16, 0.64, 1.28, and 2.00 Hz were 0.2±0.1 (62.2±15.4), 0.3±0.2 (24.5±13.0), 0.4±0.2 (7.2±18.8), 0.5±0.1 (7.2±11.3), 0.7±0.2 (11.0±7.5), and 0.8±0.3 (4.4±14.4), respectively. In step velocity (SV) test, gains stimulating the lesion side were significantly lower than those stimulating the intact side in both low- and high-acceleration SV test (p<0.05) and per-rotatory gain stimulating the lesion side in high-acceleration SV test was significantly lower than that in low-acceleration SV test. Tc stimulating the lesion side were significantly shorter than those stimulating the intact side in low- acceleration SV test (p<0.05) but not in high-acceleration SV test. Per- and post-rotatory Tc in high-acceleration SV test stimulating the intact side was significantly lower than those in low-acceleration SV test (p<0.05). Conclusion: At high-frequency SHA test, gain was pretty normal and phase lead was observed in some patients. High-acceleration SV test showed shortened Tc regardless of the sides, suggesting that high-acceleration SV test can reveal the impaired velocity storage system in patients with vestibular neuritis more frequently than low-acceleration SV test.
Initiation of Smooth Pursuit in Acute Cerebellar Infarction: A Preliminary Study
Tae Ho Yang, Sun Young Oh
Res Vestib Sci. 2013;12(2):47-53.
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Background and Objectives: The cerebellar lesion causes an initiation deficit of smooth-pursuit eye movement depending on the location of the lesion. We investigated the initiation of smooth pursuit in patients with cerebellar infarction and in healthy subjects, using step-ramp stimuli. Materials and Methods: Ten patients with cerebellar infarction documented by brain magnetic resonance imaging and fifty healthy subjects are recruited. To estimate the initiation of smooth pursuit, the onset latency and initial acceleration during the first 100ms of the horizontal smooth pursuit were estimated using the step-ramp target stimuli (5°/sec, 10°/sec, and 20°/sec). Results: In healthy subjects, onset latency of pursuit was shortened and initial acceleration was increased as target velocity was increasing. In patients with unilateral cerebellar infarction, the onset latency of ipsilesional smooth pursuit was significantly delayed at the target velocities of 10°/sec and 20°/sec. For the fast target velocity of 20°/sec, there was significant decrease of the initial acceleration of contralesional pursuit. Conclusion: In comparison with the healthy subjects, the patients with unilateral cerebellar lesions showed significant delay of pursuit onset and decrease of initial eye acceleration in the fast target velocity. These results support that the cerebellar lesions affect not only steady-state smooth pursuit gain but also the processing time required to initiate smooth pursuit, i.e., onset latency and initial acceleration. More extensive study is needed to confirm the role of cerebellum for parametric adjustment of each component of smooth pursuit.

Res Vestib Sci : Research in Vestibular Science
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