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This study investigated whether conductive hearing loss reduces normal binaural hearing advantages and whether binaural hearing advantages are normal in patients who have had hearing thresholds improved by middle ear surgery. Binaural hearing was assessed at a test frequency of 500 Hz using the masking level difference and interaural time discrimination thresholds. Results indicated that binaural hearing is often poor in conductive lesion patients and that the reduction in binaural hearing is not always consistent with a simple attenuation of the acoustic signal. Poor binaural hearing sometimes occurs even when middle ear surgery has resulted in bilaterally normal hearing thresholds. Our preliminary results are consistent with the interpretation that auditory deprivation due to conductive hearing loss may result in poor binaural auditory processing.

The author and his associates still strongly recommend an office closure treatment for central tympanic membrane perforations, which has resulted in 1449 healed perforations over a period of 36 years. A particularly gratifying segment of the healed perforation population has been the 247 residual or recurrent perforations following myringoplasty or tympanoplasty surgery that were closed by office treatment. Thus, the patients were spared a second operation. After reviewing his own and his associates' surgical failures, the author found two factors that seem to predispose to surgical failure. Primary failures or recurrent perforations following surgical repair occur most frequently in patients with neglected or inadequately treated upper respiratory tract allergy. There also appears to be a higher incidence of primary failure or recurrent perforations when an operative approach does not provide an excellent view of the anterior annulus during surgery. This would seem to be the case with the routine use of the transcanal or endomeatal approach. Furthermore, the author also objects to the routine use of a combined endomeatal and postauricular approach, which may permit an unobstructed view of the anterior annular region by tilting the patient away from the surgeon during surgery. If there is a prominent anterior bony canal wall bulge, and there is an anterior graft failure or recurrence, reoperation, rather than a few office treatments, is the only recourse. The visualization problems both during and following surgery as described have led the author to continue his use of the endaural approach and meatoplasty learned during years of fenestration surgery and to adhere to the surgical technique described.

A twelve-year experience with banked homograft ossicles has developed into a system of presculptured incus allografts adapted for the correction of many ossicular defects encountered in tympanoplasty and revision stapes surgery. The standardized preparation of a number of variations of modeled incus prostheses for an operating room bank by a well-trained ear homograft laboratory technician has been an effective and time-saving technique.

Our literature review has tabulated 33 jugular foramen neuromas that appeared either as a neurologic "syndrome of the jugular foramen" like a glomas tumor, or similar to an acoustic tumor. The few posterior fossa tumors involving the eighth nerve or encroaching upon it that have been removed and resulted in cochleovestibular preservation or recovery have been reviewed. A rare case of jugular foramen schwannoma with cochleovestibular preservation after total removal has been extensively studied with preoperative and postoperative cochleovestibular tests.

Three cases of middle ear and mastoid neoplasms are reported as "adenomatous tumors" since in their search of the literature the authors did not find any previously described lesions with a similar histologic appearance and benign biologic behavior. Microscopically, all three tumors are similarly composed of solid cords and nests of closely-packed small cells having an epithelial appearance. Two distinct cell types are present: cuboidal cells, arranged in a rudimentary gland-like pattern, and angular cells forming irregular nests with no distinct pattern. All three tumors developed in patients in their 20's, over a period of months with minimal symptoms; yet in all of the lesions the tympanic membrane was intact at the time of initial examination. None of the neoplasms was diagnosed preoperatively, and, once removed, all three tumors were pathologic enigmas and therapeutic problems in view of the initial and subsequent consultant pathologic opinions; nevertheless, total local excision with preservation of the tympanic membrane would appear to be safe treatment in these cases. The term "adenomatous tumor" is applied to these three neoplasms because: 1. a true glandular epithelial origin warranting the term adenoma or adenocarcinoma cannot be proven; and 2. the biologic behavior and prognosis is not necessarily reflected by the histologic appearance. A more specific term reflecting the origin and behavior of these tumors does not appear possible without the study of further cases.

Previous investigations have shown that binaural hearing is often abnormal in patients having conductive hearing losses, and even in patients who have had hearing thresholds corrected by middle ear surgery. The present study assessed further the masking-level difference (MLD) in patients who had previously undergone middle ear surgery. The stimuli were chosen such that the sensitivity to interaural time difference cues and to interaural amplitude difference cues could be assessed independently. Results indicated that the MLD is abnormal in more than a third of 15 patients, even after surgery has restored normal hearing at the frequency of the test. The MLD is more likely to be reduced for the cue of interaural time difference than for interaural amplitude difference. Subjects who had lesions of long duration, early onset, and large asymmetry were particularly likely to have reduced MLDs.

A review of 217 consecutive revision stapes operations performed during a ten-year period revealed that the surgeon encounters more pathological variables than he does during primary operations. Hence, the technical solutions are less stereotyped and the net results less predictable. Prosthesis displacement, with or without incus tip erosion, was the most common primary cause of failure (82%). However, oval window problems such as footplate refixation, perilymph fistula, otosclerotic regrowth, and lateralized oval window membrane in 60% of cases often complicated prosthesis displacement. First revision operations in 174 cases resulted in postoperative bone-air deficit of 10 dB or less in 65% of cases, much better than the 45% for second revision results, and the 25% for third revisions. These statistics provide our practice with a realistic prognosis when discussing revision stapes surgery with the individual surgical candidate.