Search PubMed⌕ Search

Biomedical subjects

A G Kerr

Publications and source records attributed to A G Kerr.

At least 19 recordsLinked to original sources
PubMed1992

Non-surgical management of acoustic neuromas.

Watchful waiting is one of the options available in the management of acoustic neuromas and this article deals with 13 patients who were so managed. Non-operative management was advised because of age, poor general health, small size of tumour, only hearing ear, or in patients unwilling to undergo surgery for various reasons. This group was followed up at 6-12-monthly intervals and the follow-up period ranged from 1 to 18 years (mean 5.3 years). Ten patients had small tumours and only in 2 of these was increase in tumour size demonstrated on follow-up CT scan. In one this increase was later followed by regression. Two patients required partial removal of tumour because of increasing symptoms after 3 and 7 years of follow-up; one of them died on the twelfth post-operative day. There appears to be a small group of patients for whom delay is worth while rather than to subject all patients with acoustic neuroma to surgery from which full recovery cannot be guaranteed.

Adolescent↗
PubMed1992

Acoustic neurinoma surgery in Belfast 1986-1989.

Forty-seven acoustic neurinoma tumours have been operated on in 46 patients in the years 1987-1989. This is a considerable increase over the prevalence in the preceding ten years. Twenty-six were classified as large tumours, 18 as medium and one was small. Surgical excision was complete in 16 and incomplete in 31 cases. Two patients died in the early postoperative period. Facial nerve function was preserved in 36 (80%) of cases; of these 27 (60%) had good function and nine (20%) fair function. Useful hearing was prevented in only two patients. The overall complication rate has been low and often of a transitory nature.

Adult↗
PubMed1991

Otological manifestations of a new familial polyostotic bone disorder.

Fifty members of a family with a unique autosomal dominant bone disease were investigated. Nineteen of the family members were either known to have, or were strongly suspected of having the disease. All but one of these had a hearing loss which was conductive in the younger age group and mixed in the older members. The common finding in those who had middle ear surgery was replacement of the long process of incus by a fibrous band. The histological features were similar to those found in Paget's disease. The age of onset, distribution of lesions and radiographic findings, however, were not typical of this disorder.

Adult↗
PubMed1991

Realities in ossiculoplasty.

The results of ossiculoplasty are frequently reported in terms of closure of the air-bone gap. This parameter is a reliable indicator of the degree of technical success, and is useful in comparing different materials and types of reconstructions. However, assessment of the operated ear alone does not evaluate the effect of surgery on binaural hearing ability, leading to the situation where sub-optimal advice may be given to patients pre-operatively. This article advocates a more patient orientated method of assessing the results of ossiculoplasty. Previous studies have indicated that the operated ear must reach an air conduction level of 30 dB for the speech frequencies, or be within 15 dB of the other ear, to ensure that the patient will gain significant benefit. A graphical method for the prediction of patient benefit is presented, and compared to the rule of thumb quoted above. The implications for surgeons and patients considering ossiculoplasty are obvious. Many statements routinely made to patients prior to surgery for conductive hearing loss are unduly optimistic and unrelated to the realities of reported results. There is a need to determine what types of such hearing losses can be helped surgically, and more importantly to what extent the patients hearing disability can be relieved.

Cholesteatoma↗
PubMed1991

Realities in ossiculoplasty.

The results of ossiculoplasty are frequently reported in terms of closure of the air-bone gap. This parameter is a reliable indicator of the degree of technical success, and is useful in comparing different materials and types of reconstructions. However assessment of the operated ear alone does not evaluate the effect of surgery on binaural hearing ability, leading to the situation where sub-optimal advice may be given to patients pre-operatively. This article advocates a more patient orientated method of assessing the results of ossiculoplasty. Previous studies have indicated that the operated ear must reach an air conduction level of 30dB for the speech frequencies or be within 15dB of the other ear to ensure that the patient will gain significant benefit. A graphical method for the prediction of patient benefit is presented, and compared to the rule of thumb quoted above. The implications for surgeons and patients considering ossiculoplasty are obvious.

Consumer Behavior↗
PubMed1989

Role and results of cortical mastoidectomy and endolymphatic sac surgery in Menière's disease.

It is almost impossible to establish the natural history of Menière's disease and, by the same token, it is difficult to confirm the efficacy of endolymphatic sac surgery. The authors doubt the logic of sac operations. Only two controlled trials of sac surgery have been found and both cast doubt upon its value. There do not appear to be any controlled trials indicating that it works. In 14 cases of incapacitating Menière's disease, where vestibular nerve section was indicated, cortical mastoidectomy was offered and accepted in the expectation that two-thirds might be spared the more major procedure. In the event, the vertigo was controlled in eight out of 14 (57 per cent), the remaining six (43 per cent) requiring more major surgery. A surgical model illustrates that, of themselves, these results are essentially meaningless in assessing the efficacy of cortical mastoidectomy in Menière's disease. Until all cases in a community are considered and followed-up, we shall be in doubt about the value of sac surgery and most other treatments of Menière's disease.

Endolymphatic Sac↗
PubMed1989

Transplanted ossicles after two decades.

The authors now report on the histological appearance of two very long-term ossicles, an autologous incus removed from the middle ear at revision surgery 21 years after repositioning and a homologous incus removed from the middle ear after 20 years. Having been placed in formalin immediately after removal from the ear, both specimens were later decalcified by ethylene diamine tetra-acetic acid, embedded in paraffin wax, serially sectioned and stained with haematoxylin and eosin.

Bone Regeneration↗
PubMed1989

Tympanosclerosis: a scanning electron microscopic study.

Twelve specimens of tympanosclerosis were examined. Six were immediately fixed in 3% glutaraldehyde and 6 were obtained from the departmental collection of specimens in wax blocks which had previously been examined by light microscopy. Seven specimens were demineralized. The material was examined macroscopically, by light microscopy and by scanning electron microscopy to a magnification of x25,000. The microstructure of tympanosclerosis is an irregular three-dimensional collagen lattice, enclosing distinct, spherical, mineralized aggregates, housed in lacunar-like spaces. This lattice is continuous with the plaque surface which is an envelope, probably of proteinaceous material. The spherical calcified aggregates were absent from the demineralized specimens. There was no structural difference in the scanning electron microscopic appearances of specimens processed conventionally in 3% glutaraldehyde and those previously embedded in wax.

Adult↗
PubMed1989

Pneumatization of the posteromedial air-cell tract.

Sixty consecutive temporal bone specimens were examined histologically by light microscopy to determine the incidence of a pneumatized posteromedial air-cell tract extending into the posterior wall of the internal auditory meatus. Thirteen were found to have this air-cell tract. The main potential surgical hazards of opening this air-cell tract are CSF otorhinorrhoea and meningitis.

Cerebrospinal Fluid Otorrhea↗
PubMed1978

Ossicular replacement prostheses.

To find a way of improving the results of ossicular reconstruction in ears that were rendered hard of hearing by chronic otitis media, the suitability of two biocompatible materials has been investigated. After three years' experience with Proplast and two years with Plastipore, it is concluded that for ears which lack an incus and stapes arch, these materials provide results at least as good as those previously reported with homologous materials and have the advantage of easy manipulation, timesaving, and ready availability. As with all foreign material in the chronically infected middle ear, the risks of extrusion cannot be ignored. The results so far indicate that this problem can be overcome with the use of cartilage film to separate the prosthesis from the tympanic membrane.

Auditory Threshold↗
PubMed1978

Ganglion cell populations in normal and pathological human cochleae. Implications for cochlear implantation.

A histological study of 100 hearing ears showed that some capability for speech discrimination requires at least 10,000 spiral ganglion cells. The spiral ganglion cell populations were then estimated in another group of 62 ears which were profoundly deaf for a variety of causes and it was found that 45% of these met the criterion of having 10,000 ganglion cells. The ganglion cell populations were largest in ears deafened by sudden deafness, Meniere's Disease, and ototoxic drugs; they were somewhat less for those with vascular occlusion, temporal bone fracture, otosclerosis, and cochlear dysplasias; they were least in those with measles, bacterial labyrinthitis and congenital syphilis. The data is of relevance in the selection of patients for cochlear implantation.

Adolescent↗