摘要:

Pure-tone sensitivity was serially monitored in a patient with a surgically confirmed cerebellar tumor that extended up to and involved the brain stem, primarily on the left side. During the observation period, the audiogram on the right ear consistently showed normal pure-tone sensitivity. In contrast, the audiogram on the left ear consistently showed a low frequency hearing loss. The low frequency hearing deficit was primarily confined to the frequency of 250 Hz. This report documents the reality of low frequency hearing loss in central auditory disorder.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

When a patient reports that he experiences voices, music, or other complex auditory perceptions in the absence of appropriate stimulation, the examiner suspects auditory hallucinations associated with psychosis or central nervous system (CNS) disorders. When the patient reports ringing or other such simple auditory perceptions, the examiner suspects tinnitus, symptomatic of otologic or neurologic dysfunction. However, a syndrome consisting of vivid auditory imagery recapitulating past experiences which is associated with hearing impairment rather than with psychosis has been defined and discussed in the literature. Only eleven case histories of this seemingly rare phenomenon have appeared in the English literature. Therefore, it was surprising to find six persons exhibiting this syndrome among a group of seventy-eight patients with tinnitus examined by otolaryngologists and referred to us for evaluation of tinnitus during the past eighteen months. This unusual occurrence suggests that this phenomenon may be more common than previously recognized and that there may be some relationship between tinnitus and this syndrome. Possible causes for the hearing impairment and tinnitus of these patients included noise exposure, acoustic trauma, ototoxicity, otosclerosis, and presbycusis. Speculation as to the mechanism underlying the tinnitus and the auditory imagery is tendered, and an appeal to otolaryngologists and audiologists to question their patients concerning this syndrome is made.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Use of Plasti-Pore‡ prostheses as ossicular replacements is based on the belief that they are well tolerated in the middle ear. Partial ossicular replacement prostheses (PORPs)‡ and total ossicular replacement prostheses (TORPs)‡ removed by surgeons of the Otologic Medical Group, Inc., in Los Angeles for revision surgery are the subject of a preliminary histologic study to determine if there is any immunologic reaction.Gross examination of PORPs and TORPs removed for revision tympanoplasty shows that their shape is maintained and that fibrous tissue grows both inside and outside the prostheses. These factors can be considered evidence of inertness. The present histologic study describes the type of cells found in the fibrous tissue.Light and electron microscopic studies show that macrophages and foreign body giant cells are present in the fibrous tissue. Many of the cells surrounding the prostheses contained particulate dustlike pigment.The significance of the presence of these cells is not known; however, this preliminary study shows that the middle ear reacts to the prostheses as though they were foreign bodies. This reaction indicates the need to study the long-term tolerance of Plasti-Pore and the relationship of immunologic reaction to extrusion. Until more is known about the middle ear reaction, use of cartilage grafts between the prostheses and the tympanic membrane is advocated as a means to lower the extrusion rate.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Ninety-two unsuccessful cases out of a series of 5291 cases of stapedectomy were analyzed by examining the original surgical findings, the postoperative courses, the surgical findings at the revision surgical procedure, the revision surgical technique, and the subsequent hearing results.This analysis includes a discussion of the surgical findings at the revision surgical procedure of conductive hearing loss cases. Categories of surgical findings include eroded incus, prosthesis malfunction, negative findings, malleus fixation, adhesions, vein lateralization, otosclerosis regrowth, tissue reaction, and fistula. Also, the audiologic patterns of the unsuccessful cases before the revision surgical procedure aid in predicting both what to do and the subsequent hearing results. Finally, experience with a revision surgical procedure in the unsuccessful cases with sensorineural hearing loss is detailed.The discussion section of this study also points out how to avoid unsuccessful hearing results when undertaking a revision surgical procedure.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

The practical use of the cochlear implant in profoundly deaf patients has sometimes been impaired because a stable nonmoving application of the external inductor coil directly over the internal coil has been very difficult to achieve. The authors believe that implanted magnets may solve this problem.We have found that permanent magnets can be incorporated into the external and internal inductor coil assemblies to provide this transcutaneous positioning.The effects of subcutaneously implanted samarium cobalt magnets were tested in dogs to search for adverse tissue response from either the magnetic field or skin compression between external and internal magnets.In vitro testing of the magnet-modified implant apparatus across primate skin shows a linear relationship of the primary and secondary voltages. Thus both biologic testing and electronic coupling results indicate that small, powerful magnets can be safely incorporated into existing cochlear prosthesis design.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Eight patients with vertiginous symptoms but without auditory or central nervous system symptoms were treated by middle fossa vestibular nerve section. The removed segment of the vestibular nerve with Scarpa's ganglion was studied under light and electron microscopes. No sign of infection was observed. Most of the nerve fibers and ganglion cells appeared normal. The major pathologic changes observed were increase of endoneurial collagenous tissue and occurrence of clusters of myelinated and unmyelinated nerve fibers with small diameters. These changes indicate a mild degenerative process involving the vestibular nerve. Because these changes are morphologically similar to experimentally produced mild chronic compression lesions in the peripheral nerves, and because local anatomic changes in the internal auditory canal (IAC) have been seen in 50 percent of the presented cases to cause its narrowing, chronic compression on the vestibular nerve within the IAC is suggested as a possible etiologic factor. The observed changes are not exclusive to the described types of vertiginous disorders; they may also be found in other disorders that produce vestibular and cochlear symptoms.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Numerous genetic syndromes are now known in which hearing loss is a key feature.1Most of these disorders are transmitted in a mendelian fashion, but a few are due to some chromosomal aberration. In 1974 one of the authors (R.G.)2reported a child with partial hearing loss and multiple congenital malformations caused by the presence of a microchro-mosome. Emphasis at that time was given to the patient's cardiovascular and hand malformations. Since this child's main functional problem has always been one of hearing loss, it seems worthwhile to give a detailed account of his unusual middle ear defect and the surgical treatment that was instituted. Furthermore, additional chromosomal information is now available.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

A 0.125-inch thick sheet of Vivosil was utilized to close a defect in the tegmen. It was inspected physically fifteen years after insertion. This is undoubtedly one of the longest recorded cases of such utilization. The graft had neither slipped nor moved, nor had it failed to cover the tegmen defect. It remains in place after nearly seventeen years.

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID

ISSN:0192-9763    

出版商:OVID    

年代:1980

数据来源: OVID