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This article reviews the development of surgical methods over the centuries to improve hearing loss due to otosclerosis. Pioneers in the development of surgical techniques for otosclerosis discussed in this article include Holmgren, Lempert, Rosen, and Shea. Also discussed are the personal experiences of the author, witness to many of this century's technologic developments and founder of the House Ear Institute in Los Angeles, California.

When a patient presents with bilateral progressive hearing loss and has a family history of hearing loss, otosclerosis should be placed high on the list of possible causes. Primary care physicians should determined whether the hearing loss is conductive or sensorineural with otologic examination and tuning-fork evaluation. Unless there is an obvious reversible cause for the progressive hearing loss, the patient should be referred to an otolaryngologist for more intensive otologic and audiologic examination. The patient's principal concern is the ability to hear and comprehend the spoken word in normal circumstances. Fortunately, most patients can be rehabilitated with surgery or a hearing aid. Fluoride treatment may have a significant role in preventing further hearing loss from otosclerosis.

Human stapes crura obtained at the time of stapedectomy for clinical otosclerosis have been studied after removal of the mucosal and periosteal layers by treatment with hydrogen peroxide and ultrasonification. With the scanning electron microscope, four basic architectural patterns are evident: honeycomb, fibrillar, compact and pitted. The significance of these patterns is as yet unclear, but they do appear to be in intimate relationship one to another and perhaps are varying stages in a single process.

Progressive hearing loss is a potential complication of Paget's disease, a metabolic disorder of accelerated bone formation and resorption. Calcitonin (Calcimar) is a recently introduced synthetic hormone used as a systemic treatment. Some studies have shown it to halt the progression of hearing loss. This is the first study of the effects of calcitonin on hearing loss to use a large number of patients with continuous use of the drug and long-term follow-up. It confirms that the drug is effective. We conducted chart reviews to compare the degree of hearing loss over time in 45 patients. Twenty-six patients have been taking salmon calcitonin for five to eight years to date and nineteen have received no treatment. Hearing loss was recorded at the initial examination (trial 1), one to four years later (trial 2), and then one to five years after the second evaluation (trial 3). Statistical analyses show a strong relationship between treatment and rate of hearing loss. The average hearing loss in the control group progressed from 47 dB in the first trial to 59 dB in the second trial to 75 dB in the third trial. Average hearing loss in the treated group remained at 47 dB over time. The difference in hearing loss over time between the two groups was less than 1 dB for the treated group and more than 28 dB for the control group. Results thus clearly show that calcitonin is effective in halting the progression of hearing loss in Paget's disease.

We reviewed the records of 498 primary stapedectomy cases in regard to duration of disease, age at surgery, oval window pathology, hearing results, dizziness, and tinnitus. Ninety percent of the cases in which a tissue graft had been used as an oval window covering obtained a postoperative hearing level within 10 dB of the preoperative bone conduction. Postoperative sensorineural hearing impairment occurred infrequently and was two to three times more common in cases in which Gelfoam had been used as an oval window covering as compared to tissue grafts. Postoperative dizziness of one degree or another persisted at four months in 2 percent of the cases and was a problem for the patient in two cases (0.4%). This dizziness was likewise more common in Gelfoam cases. We concluded that tissue grafts are a better covering for the oval window than Gelfoam both in regard to hearing improvement and lack of postoperative complications.

We reviewed the records of 258 revision stapedectomy operations performed at the Otological Medical Group during an eight year period. Displacement of the prosthesis to the inferior edge of the window was the commonest cause of failure (41%) and occurred predominately in wire-Gelfoam pad cases. An oval window fistula, a short prosthesis or bony closure of the window were causes of failure in 9% each. Incus necrosis was the cause of failure in 5%. Less than 50% of the operations resulted in postoperative conductive deficit of 10 db or less. The results were better than this in incus bypass procedures, in revisions of cases in which a tissue graft was used over the oval window and in revisions of ears initially operated on elsewhere. Severe sensorineural hearing impairment was the result in 7% of the operations and half of these impairments were dead ears. The majority of these adverse results followed a repeat drill out of obliterative otosclerosis or followed reopening of the oval window in patients with a postoperative inner ear problem other than a fistula. We concluded that 1. revision stapedectomy is a less satisfactory procedure than primary stapedectomy; 2. there is rarely an indication for a repeat drill out of obliterative otosclerosis; and 3. the oval window membrane usually should not be disturbed in revision stapedectomy in a patient with inner ear symptoms unless there is a fistula.

To determine new guidelines for stapedectomy in patients with both Meniere's disease and otosclerosis, we studied the position of the saccular membrane and Reissner's membrane in relation to the stapes footplate in eight temporal bones from patients with Meniere's disease. We also reviewed charts of four patients with both otosclerosis and Meniere's disease who had stapedectomy. Histologic and clinical findings were compared with preoperative bone conduction levels at 500 Hz and at high frequencies. We found that the saccular and Reissner's membranes did not contact the stapes footplate ain bones of patients with preoperative bone conduction levels of 35 dB or better at 500 Hz and no high-frequency loss. We also found that stapedectomy was successful in patients with the same criteria. We therefore conclude that stapedectomy does not increase the risk of sensorineural hearing loss for patients with otosclerosis and Meniere's disease who have bone conduction levels of 35 dB o better at 500 Hz and no high-tone loss, but it is contraindicated for patients with 45 dB at 500 Hz or worse and with high-tone loss.

The crura of normal human stapes were studied with the scanning electron microscope. Three definite layers were seen: mucosal, periosteal, and bone. The appearance of each layer, as well as of the transition zones, has been presented. Familiarization with the scanning electron microscopic features of the normal human stapes crura should make identification and interpretation of abnormal features of diseased states apparent.

In this long-term follow-up study of fenestration cases, a remarkable stability in sensorineural hearing levels is demonstrated. Since the focus of otosclerosis was not removed at the time of fenestration surgery, this bone conduction stability is an indication that the ear can withstand the presence of an otosclerotic lesion that produces stapes fixation for long periods of time without sensorineural deterioration. It would seem that the otosclerotic lesion in ears suitable for fenestration surgery has had little tendency to invade deeply into the cochlear capsule.