D. Thane R. Cody

Congenital Cholesteatoma of the Ear

Congenital cholesteatoma of the ear is a capricious and challenging problem for the otologist. We present 21 cases managed at the Mayo Clinic from 1961 to 1983. In all but one unusual case, the cholesteatoma developed behind an intact tympanic membrane and there was no history of aural infections. Preoperative symptoms and signs were predominantly conductive deafness with either a normal tympanic membrane or an opaque, whitish appearance to the drum. Disease was located in the middle ear or in the middle ear and mastoid, except in one patient who had cholesteatoma extending into the petrous apex. Surgical management depended on the extent of the lesion, and recurrences were unusual, suggesting that congenital cholesteatoma may not be as aggressive as acquired cholesteatoma.

Otosclerosis: vestibular symptoms and sensorineural hearing loss.

Of 546 patients with otosclerosis, 500 who had not had ear surgery were divided into four groups according to the relative and absolute amounts of sensorineural hearing loss in the hearing-impaired ears. The first three groups of patients had progressively less of a conductive component and progressively more of a sensorineural component to their hearing losses. The fourth group of patients had pure sensorineural hearing impairments. The remaining 46 patients were placed in group V. They had bilateral hearing losses and had had a prior unilateral stapedectomy for otosclerosis and they had received medical therapy for otosclerosis. The following conclusions were reached: 1 Further clinical evidence was obtained supporting the existence of the entity “pure labyrinthine otosclerosis.” However, there can be difficulties in the diagnosis of this condition. 2 The incidence of vestibular symptoms in patients with otosclerosis increased as the relative and absolute amounts of sensorineural hearing loss increased and was much higher than one would expect in the normal population. In addition, with increasing sensorineural hearing loss, the severity of vestibular symptoms increased along with the incidence of depression in vestibular function determined by the bithermal caloric test in patients with vestibular Symptoms. 3 A preliminary study on the administration of a combination of calcium gluconate, sodium fluoride, and vitamin D to patients with otosclerosis who had vestibular symptoms indicated that the therapy controlled vestibular symptoms in a high percentage of these patients. 4 A preliminary study on the administration of calcium gluconate, sodium fluoride, and vitamin D to patients with otosclerosis indicated that in a high percentage of patients the deterioration in hearing was stopped. A small but significant number of patients had reversal of their hearing loss. 5 Side effects of treatment with a combination of calcium gluconate, sodium fluoride, and vitamin D were not serious and were reversible, and there appears to be no contraindication to this therapy for healthy adults.

Benign chondroblastoma of the temporal bone.

Benign chondroblastoma is a rare tumor in the temporal bone. It occurs preponderantly in middle-aged men as a mass in the posterosuperior region of the ear canal and is accompanied by hearing loss. On pathologic examination, giant cells and focal regions of chondroid differentiation are noted. After the extent of the tumor has been determined, the treatment is surgical removal. Preoperative irradiation may be helpful. Long-term follow-up is essential.

Obliteration of vestibular and cochlear aqueducts in the guinea pig

The study involved 42 healthy adult guinea pigs placed into two major groups. In group A, only histologic studies were performed after obliteration of the right vestibular aqueduct, the cochlear aqueduct, or both the vestibular and cochlear aqueducts. In group B, hearing changes were monitored by repeated determination of averaged temporal response thresholds after the same obliterative operations as in group A. At the conclusion of the experiments, histologic studies of temporal bone were performed and hearing changes were correlated with the severity of disease found in the inner ear.

Tympanoplasty: Long-Term Results

Long-term results after 878 tympanoplasties using five different methods of repair were analyzed. The five groups were as follows: canal skin and fascia, single fascia, double fascia, canal skin, and canal skin and homograft tympanic membrane. Ten percent of the graft failures occurred 18 months or longer after operation. The highest percentage of graft takes (88%) and satisfactory hearing improvement (socially adequate level 87%, air-bone gap closure to within 15 dB 76%) and the lowest incidence of depression in cochlear reserve (0.7%) was in the double fascia group. Overall hearing results achieved in the 878 tympanoplasties were poorer than anticipated. Differences in results in the five groups, although occasionally large, were not statistically significant. Differences in the percentage of successful graft takes in ears that had no active disease as compared with ears that had active disease and in primary operations as compared with revision operations were not statistically significant. Complications encountered were common and varied.

Experimental Facial Nerve Paralysis: Influence of Decompression

An experimental model was employed to establish an endotemporal bone facial nerve paralysis in cats. Twelve facial nerves were initially surgically decompressed— Both bony decompression and sheath decompression—to determine if any harm was done to the nerves by these procedures. Transient harm was found in 3 of the 12 nerves. After the course of the facial paralysis without any decompression was determined, 39 cats underwent either bony or sheath nerve decompression, both immediately after injury and after a delay. The cats were followed clinically and electrophysiologically; the nerve excitability test and the amplitude and latency of muscle response evoked by nerve stimulation were used to evaluate nerve function. While immediate postinjury bony decompression resulted in slightly earlier recovery times, immediate sheath splitting significantly lengthened recovery times and worsened the electrophysiologic test results. Histologic studies confirmed the clinical and electrophysiologic results anatomically. Delayed nerve decompression, either bony or sheath, was not associated with faster recovery rates.

Tympanoplasty: Long‐term hearing results with incus grafts

The purpose of this study was to analyze long‐term hearing results in 122 tympanoplasties with incus repositioning and in 64 tympanoplasties using a homograft incus. The mean postoperative follow‐up period in the autograft incus group was 56 months (range 18 to 95 months) and in the homograft incus group 54 months (range 28 to 87 months). Results were compared after incus placement between the tympanic membrane‐malleus complex and stapes head and placement between the tympanic membrane‐malleus complex and stapes footplate. In each group, hearing results tended to be better after malleus‐to‐stapes head placement. There was no statistically significant difference in the results achieved when similar incus placements in the two groups were compared. When the data on malleus‐to‐stapes head tympanoplasty (152 patients) and malleus‐to‐stapes footplate tympanoplasty (34 patients) in each group were combined, the results with malleus‐to‐stapes head placements were considerably better (P = 0.01). The best hearing results were not satisfactory, however, with only 54 percent of the malleus‐to‐stapes head placements achieving a socially adequate hearing level and the air‐bone gap being closed to within 15 db on only 32 percent.

Homograft tympanic membrane in cats.

A total of 91 cats were evaluated to determine the effectiveness and nature of closure of total tympanic membrane perforations with homografts preserved in buffered formaldehyde, 70 percent alcohol, benzalkonium in Tis‐U‐Sol (1:750 solution), or Cialit (1:5,000 aqueous solution). Controls consisted of unoperated ears, ears with partial and total perforations that were not grafted, ears in which the total tympanic membrane was removed and immediately replaced, and ears grafted with fresh homograft tympanic membranes.