No abstract available.
Cochlea*

Objective This study aims to measure the complete and two-turn cochlear duct lengths in a Filipino population using archived CT scan images.
Cochlea ;

No abstract available.
Anoxia* ; Cochlea* ; Diuretics* ; Guinea*

Labyrinthine fistula caused by cholesteatoma can make various complications according to the site of the lesion. The lateral canal, superior canal ampulla, posterior canal and promontory of the cochlea are the common areas of fistulization. However, invasion into the cochlea or internal auditory canal (IAC) is very rare. We have experienced a case of cholesteatoma extending into the cochlea and IAC, which was successfully treated via the transotic approach. Herein we report this case with a review of literature
Cholesteatoma ; Cochlea ; Fistula

Objective: To describe the cochlear anatomy among Filipinos through high resolution computed tomography (HRCT) imaging. Methods: Design: Retrospective Study Setting: Tertiary Private University Hospital Patients: Cochlear images retrospectively obtained from computed tomography (CT) scans of subjects who underwent cranial, facial, paranasal sinus and temporal bone computed tomography from October 2009 to July 2010 were reconstructed and analyzed. Results: 388 cochlear images were obtained from the scans of 194 subjects (101 males and 93 females, aged 1 to 90 years old, mean = 52 years) and reconstructed for analysis. The mean coiled cochlear height measured 4.36 mm on the right (A.D.) and 4.34 mm on the left (A.S.). Measurement from the oval window to the distal end of the basal turn (equivalent to the horizontal dimension of the cochlea or the mean length of the basal turn) was 7.55 mm A.D. and 7.60 mm A.S. The vertical and horizontal dimensions of right and left cochleas were identical in all subjects (S.D. = 0.35). The right and left cochlear turns were identical in each subject, exhibiting 2 1/2 turns in 92.3% of subjects and 2 3/4 turns in 7.7% of subjects.The cochlear dimensions were similar in all subjects, regardless of age. No cochlear ossification or malformation was noted on any CT image. Conclusion The 7.55 mm mean length of the cochlear basal turn among Filipinos in this study was 1.24 mm shorter than the average length of the basal turn of 8.81 mm reported elsewhere. Further studies of the cochlear dimensions in specific age groups and its correlation to audiometric status are recommended to determine other significant physiologic correlations.
Cochlea ; Magnetic Resonance Imaging

Cochlea ; Humans ; Macrophages ; Stria Vascularis

BACKGROUND AND OBJECTIVES: The auditory efferent system -Medial olivocochlear bundle (MOCB)-controls the sensitivity and frequency selectivity of the cochlea and maintains the cochlea for optimal acoustic signaling. Contralateral acoustic sound stimulates the MOCB and has inhibitory effects on the sound evoked amplitude response of the cochlea. There are only a few reports on the latency response of contralateral acoustic stimulation (CAS) on distortion product otoacoustic emission (DPOAE), and it has no consistent conclusion. The purpose of this study was to evaluate whether changing the latency of DPOAE by CAS could be a stable method for monitoring the function of MOCB. SUBJECTS AND METHOD: The change in the latencies of DPOAE after CAS were monitored in 24 normal hearing ears with f2 sweep paradigm. The CAS level was divided into two groups, one was under 65 dB SPL and other was over 65 dB SPL. RESULTS: As f2 frequency changed from 1 kHz to 2 kHz, the latency of DPOAE was shortened from 11.82 +/- 1.87 ms to 7.29 +/- 0.86 ms in low stimulation level (50 dB SPL) and from 10.70 +/- 2.65 ms to 6.16 +/- 1.59 ms in high stimulation level (75 dB SPL) There were no significant shortening on the latency of DPOAE after CAS in low stimulation level group. But in higher stimulation level group (75 dB SPL), DPOAE latency changed from 10.70 +/- 2.65 ms to 10.12 +/- 1.95 ms (CAS level: 35 dB SL) and to 9.76 +/- 2.97 ms (CAS level: 50 dB SL) in 1 kHz, from 6.16 +/- 1.59 ms to 5.96 +/- 1.49 ms (CAS level: 35 dB SL) and to 5.83 +/- 1.28 ms (CAS level: 50 dB SL) in 2 kHz. CONCLUSION: Changes in the latency of DPOAE after CAS is not a stable monitoring tool for the function of MOCB.
Acoustic Stimulation* ; Acoustics* ; Cochlea ; Ear ; Hearing

Direction changing positional nystagmus (DCPN) is defined as a nystagmus that changes its direction with different head and body positions. In the past, it was usually thought that DCPN was the sign of central vestibular system lesion. But recently, there have been some reports that DCPN definitely does not localize the site of lesion in the central vestibular pathway, and that it more often indicates a peripheral vestibular site. However, congenital vestibular dys- or hypoplasia was not reported as a cause of DCPN. Recently, we experienced a 17-year-old patient who had a vestibular dys- or hypoplasia and showed a transient geotrophic DCPN with a normal cochlea. We report that congenital vestibular dys- or hypoplasia can be one of the causes of DCPN and present its possible mechanism.
Adolescent ; Cochlea ; Head ; Humans ; Nystagmus, Physiologic*

Labyrinthine fistula is not infrequent findings in cholesteatoma surgery. Fistula most commonly involve the horizontal semicircular canal, but a fistula into the cochlea is rare. The authors describe two cases of cochlear fistulas in chronic otitis media with cholesteatoma.
Cholesteatoma ; Cochlea ; Fistula* ; Otitis Media ; Semicircular Canals

PURPOSE: To evaluate three-dimensional volume-rendering of congenital inner-ear malfornations using the MR CISS (Constructive Interference in Steady State) sequence. MATERIALS AND METHODS: MR CISS images of 30 inner ears of 15 patients (M:F=10:5; mean age, 6.5years) in whom inner-ear malfornation was suspected were obtained using a superconducting Magnetom Vision System (Simens, Erlangen, Germany), with TR/TE/FA parameters of 12.25 ms/5.9 ms/70 degree. The images obtained were processed by means of the volume rendering technique at an advanced workstation (Voxtol 3.0.0; GE Systems, advanced workstation, volume analysis). The cochlea and three semicircular canals were morphologically evaluated. RESULTS: Volume-rendered images of 25 inner ears of 13 patients demonstrated cochlear anomalies in the form of incomplete partition (n=18), hypoplasia (n=2), and severe hypoplasia (n=5). For the superior semicircular canal, findings were normal in 15 ears, though common crus aplasia (n=6), hypoplasia (n=4), aplasia (n=3), and a short and broad shape (n=2) were also observed. The posterior semicircular canal of 13 ears was normal, but common crus aplasia (n=6), a short and broad shape (n=5), aplasia (n=4), hypoplasia (n=3) were also identified. Twelve lateral semicircular canals, were normal, but other images depicted a short and broad shape (n=7), a dilated crus (n=5), a broad shape (n=4), and aplasia (n=2). In 14 patients the anomalies were bilateral, and in seven, the same anomalies affected both ears. CONCLUSION: Three-dimensional volume rendering images of the inner ear depicted various morphological abnormalities of the cochlea and semicircular canals. At that locations, anomalies were more complicated and varied than in the cochlea. Three-dimensional volume rendering imaging using the MR CISS technique provides anatomical information regarding the membranous labyrinth, and we consider this useful in the evaluation of congenital inner ear malformations.
Cochlea ; Ear ; Ear, Inner* ; Humans ; Semicircular Canals