Effect of tympanic membrane perforation on middle-ear sound transmission

Abstract

Tympanic membrane perforation causes a sound conduction disturbance, and the size of this conduction disturbance is proportional to the perforation area. However, precise evaluation of perforation size is difficult, and there are few detailed reports addressing this issue. Furthermore, such evaluation becomes more difficult for irregularly shaped perforations. This study conducted a quantitative evaluation of tympanic membrane perforations, using image analysis equipment.A significant correlation was found between the degree of sound conduction disturbance and the perforation area; this correlation was greater at low frequencies following a traumatic perforation. The conductive disturbance associated with chronic otitis media was significantly greater at low frequencies. Circular perforations caused only minor conduction disturbance. Perforations in the anteroinferior quadrant were associated with greater conduction disturbance. Traumatic spindle-shaped perforations and malleolar perforations were associated with greater conduction disturbance.

Tympanic membrane perforation: Its correlation with hearing loss and frequency affected - An analytical study

“…Bhusal et al, [22] observed that hearing loss is greater in lower frequency when compared with higher frequencies, for all sites of perforation. Matsuda et al, [23] observed frequency dependence of hearing loss and the highest hearing threshold was of the perforations in anteroinferior quadrant.…”

Role of Multi-Detector Computed Tomography in Diagnosis and Staging of Cholesteatoma

“…Chronic suppuration can occur with or without cholesteatoma, and the clinical history of both conditions can be very similar. The treatment plan for cholesteatoma always includes tympanomastoid surgery with medical treatment as an adjunct [2,3] . Therefore, the clinician treating chronic otitis media must always have a high index of suspicion in order not to miss a critical diagnosis.…”

How Does Closure of Tympanic Membrane Perforations Affect Hearing and Middle Ear Mechanics?—An Evaluation in a Patient Cohort and Temporal Bone Models

“…Perforations on a location directly lateral to the round window were considered to increase sound pressure around the round window to a larger extent than perforations on other locations of the TM, resulting in a reduction of sound pressure difference between the oval and round windows. Ahmad et al (9) observed a larger CHL below 1500 Hz in patients with TM perforations on the posterior-inferior parts of the TM, and Masuda et al (10) found the largest CHL in patients with TM perforations on the anterior-inferior quadrant compared to the other quadrants of the TM. By contrast, significant correlation between location of the TM perforation and CHL was not observed in other clinical (6,7), and experimental studies (5,11).…”