Peak width in multifrequency tympanometry and endolymphatic hydrops revealed by magnetic resonance imaging.
OBJECTIVE
To investigate the relationship between the peak width of the characteristic "M"-shaped peak of 2 kHz conductance tympanometry and the degree of endolymphatic hydrops in magnetic resonance imaging (MRI) after intratympanic or intravenous gadolinium administration.


METHODS
Prospective study.


METHODS
An academic university hospital.


METHODS
One hundred twenty-eight ears in which multifrequency tympanometry was performed and endolymphatic space size was evaluated by MRI. Forty-five patients were examined bilaterally and 38 patients were examined unilaterally.


METHODS
Endolymphatic space size was evaluated by MRI after intratympanic or intravenous gadolinium injection.


METHODS
Endolymphatic space size was classified into three groups: none, mild, and significant in the cochlea and in the vestibule. The relationship between the degree of endolymphatic hydrops and peak width of 2 kHz conductance tympanometry was investigated.


RESULTS
The peak width in 94 ears in which significant endolymphatic hydrops was observed on MRI in the cochlea and/or the vestibule was 178.8 ± 102.7 daPa. The peak width in 21 ears in which mild but not significant endolymphatic hydrops was observed on MRI in the cochlea and/or the vestibule was 126.0 ± 77.1 daPa. The peak width in 13 ears with no endolymphatic hydrops in the cochlea and vestibule was 107.1 ± 84.1 daPa. The peak width in ears with significant endolymphatic hydrops was larger than that observed in ears with no endolymphatic hydrops. However, the peak width was not significantly different between cases of mild and absent endolymphatic hydrops.


CONCLUSIONS
Large peak width in multifrequency tympanometry was associated with significant endolymphatic hydrops.
Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, Nagoya, Japan. katoken@med.nagoya-u.ac.jp
Ken
K
Kato
Tadao
T
Yoshida
Masaaki
M
Teranishi
Rui
R
Sano
Hironao
H
Otake
Michihiko
M
Sone
Shinji
S
Naganawa
Tsutomu
T
Nakashima
D000158:Acoustic Impedance Tests; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003051:Cochlea / Q000473:pathology; D018159:Endolymphatic Hydrops / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D014722:Vestibule, Labyrinth / Q000473:pathology; D055815:Young Adult