Correlation of CT analysis and audiometry in Japanese otosclerosis

CT Grading of Otosclerosis

“…Rotteveel et al 12 obtained good interobserver agreement ( ϭ 0.77), but they did not discuss intraobserver agreement in their study. Our agreement measurements were based on 162 petrous bones, compared with 36 in the study by Rotteveel et al 12 Shin et al 8 and Kiyomizu et al 9 did not assess the reliability of their grading systems.…”

“…Grading systems of otosclerosis are also clinically relevant as many authors have shown that as the severity of cochlear otosclerosis increases, the severity of sensorineural hearing loss increases. 8,9 Cochlear otosclerosis presents with combined conductive and sensorineural hearing loss. Specific portions of the cochlea are attuned to certain frequencies of sound.…”

“…8,9 This group of patients can benefit from cochlear implantation. However, others have not been able to significantly correlate the severity of disease with the severity of hearing loss, though sample sizes were small in some of these studies.…”

“…Kiyomizu et al 9 graded fenestral disease as group A, no pathologic CT findings; group B1, demineralization localized to the fissula ante fenestram; group B2, demineralization extending toward the cochleariform process from the anterior region of the oval window; group B3, extensive demineralization surrounding the cochlea; and group C, thick anterior and posterior calcified plaques. 9 Rotteveel et al 12 described a classification system on the basis of appearance of involvement of the otic capsule: type 1, solely fenestral involvement; type 2, cochlear (with or without fenestral) involvement and divided into types 2a ("double ring effect"), type 2b (narrowed basal turn), and type 2c ("double ring effect" and narrowed basal turn); and type 3, severe cochlear involvement (unrecognizable otic capsule). No system has gained wide acceptance.…”

Correlation between the Size, CT Density of Otosclerotic Foci, and Audiological Tests in Cases of Otosclerosis

“…Shin et al [15] showed that BC thresholds were poorer in patients with endosteal involvement compared with BC in patients with fenestral otosclerosis. Kiyomizu et al [16] stated that greater BC levels were associated with a greater extent of demineralization. Hueb et al [3] showed a positive correlation between the size of the lesions, the activity, and the degree of cochlear endosteal involvement when compared to BC thresholds.…”