Sensorineural deafness inherited as a tissue specific mitochondrial disorder

285 Paired comparison judgments for hearing aid selection in children Eisenberg L.S.; Levitt H. EAR HEAR. (1991) 12/6 (417-430) Three experiments were conducted to investigate the feasibility of using a paired comparison technique to select hearing aids for children. The first two experiments determined the age at which normal-hearing children and hearing-impaired children with mild to moderately severe sensorineural hearing loss could be expected to meet criteria on a paired comparison task involving judgments of auditory clarity. Of 25 normal-hearing children between the ages of 4.0 and 6.4 yr, five out of five children between 6.0 and 6.4 yr of age passed the auditory paired comparison task. Of 10 hearing-impaired children between the ages of 5.5 and 7.4 yr, five out of five children between 6.5 and 7.4 yr of age passed the auditory paired comparison task. In Experiment 3, eight hearing-impaired children between the ages of 5.7 and 7.8 yr judged the clarity of seven hearing aids in two paired comparison, round robin tournaments. The results showed that correlations between the two tournaments were moderate to strong for six children and weak for two children. Of the six children with stronger correlations between tournaments, correlations between paired comparison judgments and phoneme identification scores were moderate to strong for four children and weak for two children. When compared with a hearing aid that approximated a standard prescription, the hearing aid selected by the paired comparison technique neither degraded nor enhanced speech intelligibility. Results from this study indicate that a paired comparison technique is feasible for use with hearing-impaired children 6.5 yr of age, and occasionally younger, who exhibit mild to moderately severe sensorineural hearing loss and are capable of performing the task reliably. Frequency speciticity of the auditory brain stem response to bone-conducted tones in infants and adults Nousak J.M.K.; Stapells D.R. EAR HEAR. (1992) 13/2 (87-95) Auditory brain stem responses were obtained from normal-hearing infants and adults in response to bone-conducted 500 and 2000 Hz tones presented in quiet and high-pass noise masking. The tones were presented at 70 (500 and 2000 Hz) and 46 (2000 Hz) dB peak to peak equivalent fre: 1 dyne RMS). The high-pass noise-masked waveforms were subtracted in succession to obtain derived responses, providing estimates of the cochlear regions contributing to the nonmasked responses. Findings indicate that the auditory brain stem response to bone-conducted 500 Hz tones is frequency specific for both infants and adults. For 2000 Hz tones, the results show maximum amplitudes for cochlear regions representing the nominal frequency of the tone for adults. For infants, maximum response amplitudes for the derived responses to 2000 Hz, 70 dB tones were obtained within i octave of the nominal frequency (1410-2000 Hz). Wave V latencies of the derived responses are similar for both groups for 2000 Hz tones, but shorter for infants to 500 Hz tones, supporting the hypothesis that low-frequency bone-conducted stimuli are effectively more intense in infants than adults. Myringoplasty for the anterior perforation: Experience with the Kerr flap Sharp J.F.; Tenis T.F.; Robinson J. J. LARYh’GOL. OTOL. (1992) 106/l (14-16) Surgical closure of the anteriorly located tympanic membrane perforation can present a problem. lack of anterior support for the graft frequently leads to graft failure if an underlay method is whereas anterior blunting is a complication of onlay techniques in this situation. The experience the Kerr flap, an underlay graft fashioned to include a tab of fascia which is placed laterally under annulus and the anterior meatal skin, is presented. This method gave a 97.5 per cent closure rate no cases of anterior marginal blunting and a mean auditory threshold gain of 8.5dB (95 per confidence limits 5 to 11.9 dB P < 0.01) was achieved at the frequencies tested. The use of the Kerr is recommended when repairing the anteriorly placed tympanic membrane perforation.

The used with the with cent flap

Sensortneural deafness inherited as a tissue specific mitochondrial disorder Jaber L.; Shohat M.; Bu X.; Fischel-Ghodsian N.; Yang H.-Y.; Wang S.-J.; Rotter J.I. .I. MED. GENET. (1992) 29/2 (86-90) We present here a large Israeli-Arab kindred with hereditary deafness. In this family 55 deaf subjects (29M, 26F), who are otherwise healthy, have been identified and traced back five generations to one

286 common female ancestor. The deafness is progressive in nature, usually presenting in infancy and childhood. Audiometry on six deaf and seven unaffected subjects was consistent with severe to profound sensorineural hearing loss. Based on formal family segregation analysis, the inheritance of deafness in this family closely fits the expectation of a two locus model owing to the simultaneous mutation of a mitochondrial gene and an autosomal recessive gene. Thus, this disorder appears to have the unusual features of being an inherited tissue specific mitochondrial disease and apparently requiring the homozygous presence of a nuclear gene for clinical expression. Most importantly, this disorder presents a unique opportunity to investigate the molecular basis of hereditary non-syndromic deafness and normal hearing. Ventilation tubes and prophylactic antibiotic eardrops Younis RT.; Lazar R.H.; Long T.E. OTOLARYNGOL. HEAD NECK SURG. (1992) 106/2 (193-195)

Insertion of ventilation tubes has successfully remedied chronic otitis media with effusion in millions of children, but the procedure has been complicated by secondary infections and otorrhea in as many as 34% of the cases. Because infection at the time of surgery was suspected as the primary cause of these postoperative complications, short-term prophylaxis with antibiotic eardrops was proposed for averting secondary infections. To evaluate this hypothesis, we conducted a 6-month prospective study in which 200 children had bilateral tube insertions. Antibiotic eardrops were administered to patients’ right ears intraoperatively and for 3 days after surgery; left ears received no eardrops and served as controls. The prophylactic strategy did not significantly decrease'the incidence of postoperative otorrhea in treated right ears compared with controls. Efficacy of acute otitis Casselbrant R.J.; Wald PEDL4TR.

antimicrobial prophylaxis and of tympanostomy tube insertion for prevention of recurrent media: Results of a randomized clinical trial M.L, Kaleida P.H.; Rockette H.E.; Paradise J.L, Bluestone C.D.; Km-s-La&y M.; Nozza E.R. INFECT. D1S.J. (1992) 11/3 (278-286)

To determine the efficacy of amoxicillin prophylaxis and of tympanostomy tube insertion in preventing recurrences of acute otitis media, we randomized 264 children 7 to 35 months of age who had a history of recurrent otitis media but were free of middle ear effusion to receive either amoxicillin prophylaxis, bilateral tympanostomy tube insertion or placebo. The average rate of new episodes per child year of either acute otitis media or otorrhea was 0.60 in the amoxicillin group, 1.08 in the placebo group and 1.02 in the tympanostomy tube group (amoxicillin vs. placebo, P < 0.001; tubes vs. placebo, P = 0.25). The average proportion of time with otitis media of any type was 10.0% in the amoxicillin group, 15.0% in the placebo group and 6.6% in the tympanostomy tube group (amoxicillin vs. placebo, P = 0.03; tubes vs. placebo, P < 0.001). At the 2-year end point, the rate of attrition was 42.2% in the amoxicillin group, 45.5% in the placebo group and 26.7% in the tympanostomy tube group. Adverse drug reactions occurred in 7.0% of the amoxicillin group and persistent tympanic membrane perforations developed in 3.9% of the tympanostomy tube group. The observed degree of efficacy of amoxicillin prophylaxis and of tympanostomy tube insertion must be viewed in light of the fact that study subjects proved not to have been at as high risk for acute otitis media as had been anticipated and in view of the differential attrition rates. We conclude that in the age group we studied, amoxicillin prophylaxis is the preferred first measure in attempting to prevent recurrences of acute otitis media and that tympanostomy tube insertion is a reasonable next alternative. Intrinsic laryngeal muscle regeneration following endotracheal Becher M.W.; Marin-Padilla M. PEDIATR. PATHOL. (1992) 12/2 (155-166)

intubation

The larynges of 33 premature and term neonates who were intubated for the management of respiratory difficulties were studied. In addition to the changes commonly associated with endotracheal intubation (epithelial erosion, ulceration, squamous metaplasia, edema, inflammation, and perichondritisl, the intrinsic laryngeal muscles were damaged in 26 of the 33 cases and, in 4 cases, oriented striated