Research in Vestibular Science

Original Articles

Positional Audiometry in Patients with Light Cupula: A Preliminary Study: Jiyeon Lee, Dong-Han Lee, Jung Eun Shin, Chang-Hee Kim; Res Vestib Sci. 2020;19(3):89-94. Published online September 15, 2020; DOI: https://doi.org/10.21790/rvs.2020.19.3.89

4,403 View
85 Download
1 Crossref

Objectives
Light cupula is characterized by persistent geotropic direction-changing positional nystagmus in a supine head-roll test. The purpose of this study is to investigate if hearing level is influenced by the change of head position in light cupula under the assumption that relative density difference similarly occurs between the tectorial membrane and endolymph.
Methods
Twelve patients with unilateral light cupula who underwent positional audiometry were included in this study. Pure tone thresholds were compared among three head positions.
Results
Hearing threshold in pure tone audiometry (PTA) of the affected ear was not different from that of the healthy ear. PTA thresholds of the affected side were not significantly different in three head positions; upright seating, cochlear apex-up, and cochlear apex-down positions.
Conclusions
Although positional change of nystagmus direction is the most significant clinical feature of light cupula, positional change of hearing level was not observed in those patients. The lack of positional influence on hearing may be explained as follows: (1) the heavier endolymph phenomenon occurs only in the vestibular end organ without involving the cochlea; (2) the light cupula phenomenon is more likely to occur due to light debris mechanism rather than heavier endolymph or lighter cupula mechanism; and (3) the effects of light cupula could be modified by outer hair cells, which work for tuning in the cochlea, even though light tectorial membrane or heavy endolymph occurs.

Citations

Citations to this article as recorded by

Light cupula phenomenon: a systematic review
Nilüfer Bal, Melike Altun, Elif Kuru, Meliha Basoz Behmen, Ozge Gedik Toker
The Egyptian Journal of Otolaryngology.2022;[Epub] CrossRef

Effect of Korean Red Ginseng on Early Vestibular Function Restoration after Unilateral Labyrinthectomy: Jiyeon Lee, Mi Joo Kim, Gyu Cheol Han; Res Vestib Sci. 2020;19(3):79-88. Published online September 15, 2020; DOI: https://doi.org/10.21790/rvs.2020.19.3.79

6,970 View
88 Download

Abstract PDF: Objectives
Vertigo is a common condition. Definitive treatment is to induce vestibular compensation. Currently, no medications have been discovered that enhance vestibular functional restoration. The current study was conducted to evaluate the ability of ordinary Korean red ginseng (KRG) to induce vestibular compensation.
Methods
Twelve Sprague-Dawley rats were divided into two groups. Five rats (KRG group) were fed KRG extract (100 mg/kg) for 2 weeks before undergoing unilateral labyrinthectomy (ULx). The remaining seven rats (control group) were untreated before ULx. After surgery, all animals were housed in the same environment without being fed additional extract. To evaluate vestibular function, gain of the horizontal nystagmus to 0.2 Hz with a peak velocity of 100°/second sinusoidal rotation was compared and analyzed before ULx as well as 3 and 7 days after surgery.
Results
Before the operation, gain of the control and KRG group were 0.81±0.05 and 0.88±0.08, respectively, with 0.2-Hz stimulation. This value decreased to 0.43±0.08 and 0.53±0.08, respectively on 3 days after operation (p=0.047), and it was 0.40±0.06 and 0.68±0.11, respectively on 7 days after surgery. The difference of gain between the two groups was statistically significant at each 3 and 7 days (p＜0.05). By confirming c-Fos protein expression in medial vestibular nuclei, the functional effect of KRG causing vestibular modulation was confirmed.
Conclusions
Rats treated with KRG showed more rapid and complete recovery after acute vestibular loss compared to untreated animals. Therefore, KRG could be one of candidate for the useful medication of vestibular diseases.

Vestibulo-Ocular Reflex Recordings of Small Rodents using a Novel Marker Array: Mi Joo Kim, Jiyeon Lee, Eui Jae Hong, Eun Ji Lee, Yu Jin Min, Dong Ju Lee, Nam Beom Kim, Gyu Cheol Han; Res Vestib Sci. 2016;15(1):11-16.

2,321 View
66 Download

Abstract PDF: Objective: Recording the nystagmus of small experimental rodents is an integral technique in vestibular research. Theoretically, the size and the shape of markers strongly affect the analysis of 3 dimensional nystagmus.
Methods
The nystagmus of 6 healthy ICR mice were recorded and their gain values were compared using 200 μm, 300 μm, 400 μm, and 600 μm isosceles triangle markers at the peak velocity of 60o/sec and 100o/sec with the rotational stimulations of 0.1 Hz, 0.2 Hz, and 0.5 Hz.
Results
The gain values of 3 different sizes of the markers showed no significant differences in horizontal- vertical-torsional component. However, it was unable to record the nystagmus with 200 μm markers since the markers were too small to be placed and stayed on the center of the pupils.
Conclusion
Technicians can decide the size of the markers from 200 to 600 ?m to record the nystagmus of mice, depending on the technicians’ skills.

First
Prev
Page of 1
Next
Last

Search