摘要:

ABSTRACTVascular compression of the vestibulocochlear (Vlllth) nerve may cause constant or recurrent positional vertigo, tinnitus, and/or hearing loss. At present the diagnosis is based upon history, physical findings, audiologic assessment, vestibular function testing, and auditory brainstem evoked responses. Delineation of the vascular and neural anatomy within the cerebellopontine angle (CPA) has not been part of the preoperative assessment.We recently treated a patient demonstrating the clinical features of this syndrome. A magnetic resonance imaging (MRI) study revealed a vascular loop of the anterior inferior cerebeilar artery intimately associated with the Vlllth nerve at the porus acusticus. To better define the significance of this finding, we retrospectively reviewed the CPA neurovascular anatomy of 100 (200 sides) otherwise normal MRI scans performed for unrelated disorders. Vessels were identified on 59.9 percent of sides while nerves were seen on 40 percent of sides. Contact between vessel and nerve occurred on 12.5 percent of sides and when both nerve and vessels were seen concurrently, they were in contact 50 percent of the time. These findings may preclude the use of MRI as the definitive diagnostic test in the preoperative assessment of vascular Vlllth nerve compression.

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

ABSTRACTAn open-ended questionnaire was administered to 53 of some of the better patients using five different kinds of cochlear implants. The subjects listed the advantages and disadvantages of their cochlear implant. Patients were asked about the time from implantation until maximum benefit and effect of the cochlear implant on tinnitus. Advantages were reported in (1) speech perception when speechreading can be used (85%); (2) environmental sound perception (75%); (3) psychologic effects (70%); (4) speech perception when speechreading cannot be used (64%); (5) lifestyle and social effects (42%); and (6) speech production (32%). Disadvantages were reported in (1) use of equipment (79%); (2) environmental-sound perception (47%); (3) speech perception when speechreading may be used (17%); (4) psychologic effects (11%); (5) speech perception when speechreading is not used (9%); (6) lifestyle and social effects (3.8%); and (7) speech production (1.9%). Ninety-one percent of the subjects indicated that they achieved maximum benefit in the first 7 months of cochlear-implant use. Eighty-one percent of the subjects with tinnitus indicated that the cochlear implant had a positive effect on their tinnitus. In 17 percent of the cases the cochlear implant had no effect on their tinnitus and in 2 percent of the cases it made the tinnitus worse.

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

ABSTRACTA multistrand wire spring prosthesis is presented for ossicular reconstruction. This device offers a workable solution not only to the ossiculoplasty problems associated with lateralization of the tympanic graft and displacement of the prosthesis, but also to other problems such as fixation to middle ear wall, tissue reaction, resorption, degeneration, biodegradation, or poor sound conduction, which are obviated using a stainless steel wire for the ossicular prosthesis. The spring also protects the inner ear from external trauma. Long-term reconstruction results of 14 cases using first generation coil spring prosthesis are presented. A freely mobile prosthesis head composed of cartilage with perichondrium on a wire-mesh platform distributes pressure evenly to the undersurface of the tympanic membrane and further ensures the prevention of pressure necrosis and extrusion. When the handle of the malleus is present, the head-loop assembly of the spring prosthesis is designed to securely capture the handle. There is no practical loss of sound energy passing through the spring. Over a period of 14 years none of the wire prosthesis was found to have eroded through the stapedial footplate.

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID

ISSN:0192-9763    

出版商:OVID    

年代:1990

数据来源: OVID