External auditory atresia and the deleted chromosome.
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Abnormalities, Multiple↗
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Treacher Collins syndrome: otologic and auditory management.
Treacher Collins syndrome (TCS) is an autosomal dominant genetic disorder, the phenotypic expression of which is seen in the head and neck area. The syndrome has full penetrance but variable expressivity even among family members, and recent investigation has reported gene site on chromosome 5q. TCS has a reported prevalence of 1 in 50,000 live births with about 40 percent of new occurrences resulting from a positive family history and a 60 percent new mutation rate. The clinical features of TCS involve bilateral abnormalities of the pinnae, external auditory canal, tympanic membrane, and middle ear space. Microtia has been reported to be as high as 85 percent, with one third of patients presenting with stenosis or complete atresia. Treacher Collins patients present with maximum conductive hearing loss often compounded by a high-frequency sensory component. This article describes the otologic and audiologic diagnosis and management of TCS.
Adolescent↗
Flow-cytometric analysis of the effects of triethylenemelamine on somatic and testicular tissues of the rat.
The effects of short-term (24 h) exposure to triethylenemelamine on cellular DNA in five tissues (bone marrow, spleen, kidney, large intestine, and testis) of the rat were studied using flow cytometry. Mean coefficients of variation of the G1 peaks were increased in both the low and high dosage groups relative to controls. Bone marrow exhibited the highest degree of effect, possibly due to the rapid rate of cell division in that tissue, and spleen was next highest. Thus, hematopoietic tissues are highly responsive to short-term, acute exposure to this mutagen. The results of the flow-cytometry assay closely paralleled a simultaneous chromosomal assay conducted on bone marrow of the same rats. These data are interpreted to be consistent with the hypothesis that the observed increase in mean coefficients of variation is due to the clastogenic effects of the mutagen and subsequent unequal distribution of DNA among the daughters of affected cells.
Animals↗
Long-term experience with biocompatible ossicular implants.
The senior author's 8-year personal experience with biocompatible ossicular implants is reviewed. Four hundred sixty-one consecutive operations, in which high-density polyethylene sponge ossicular replacement prostheses were used, are grouped according to the Bellucci classification of chronic otitis media. The prostheses used were the drum-to-footplate prosthesis (TORP, total) and the drum-to-stapes prosthesis (PORP, partial). Each group's short- and long-term hearing results are compared. Prosthesis extrusion and persistent or recurrent conductive hearing loss are the most common causes of operation failure. Failures within each group are analyzed, and techniques to prevent these complications are outlined.
Biocompatible Materials↗
Nievergelt-Pearlman syndrome with impairment of hearing. Report of three cases in a family.
Three cases of the Nievergelt-Pearlman syndrome occurring in a family are presented. In addition to the major features of the syndrome (symphalangism, carpal fusion, atypical club foot with massive tarsal fusion, and congenital dislocation of the head of the radius), all three patients exhibited conductive deafness, which had not been recorded in previous reports. The clinical findings strongly suggested that the loss of hearing was due to fusion of the ossicles of the middle ear.
Abnormalities, Multiple↗
Octylcyanoacrylate: a new medical-grade adhesive for otologic surgery.
HYPOTHESIS: The adhesive octylcyanoacrylate is not associated with significant inner ear toxicity in a guinea pig model. BACKGROUND: Many cyanoacrylate adhesives have been investigated for use in otologic surgery, but variable ototoxicity has been reported. Octylcyanoacrylate is a medical-grade adhesive with many properties that make it ideal for use in the ear. It is free of contaminants; it forms a strong, flexible bond; and it inhibits the growth of gram-positive organisms in culture. This is the first study to assess the ototoxicity of this new adhesive. METHODS: Fourteen adult guinea pigs were used. Preoperative auditory brainstem responses (ABRs) were determined. Bilateral antrotomies were performed, and the ears were randomized to adhesive and control (saline) groups. In the adhesive ears. 0.5 or 0.1 mL of octylcyanoacrylate was instilled into the middle ear. Eight weeks later, postoperative ABRs were determined, the animals were killed, and the temporal bones were removed. Middle ear changes were noted, and the ossicular chain was assessed. Cochlear hair cell analyses were performed. Histologic assessment of the middle ear mucosa was performed. RESULTS: There was a higher incidence of conductive hearing loss in the adhesive group secondary to fixation of the ossicular chain, but there was no significant difference in bone conduction thresholds. The median postoperative bone conduction thresholds (dB peak sound pressure level) was 15.0 in the control group and 17.5 in the adhesive group, p = 0.89. There was also no significant difference in inner hair cell counts (0.4% vs. 0.5% median hair cell loss, p = 0.72) or outer hair cell counts (3.7% vs. 3.0% median hair cell loss, p = 0.23) for the adhesive and control groups, respectively. Histopathologic analysis of the middle ear mucosa demonstrated variable mild to moderate foreign body reaction with no evidence of mucosal ulceration or necrosis. CONCLUSIONS: A large amount of octylcyanoacrylate placed in the middle ear of the guinea pig did not cause any morphologic or functional evidence of inner ear toxicity. This new adhesive is a promising tool for otologic surgery.
Animals↗
[Stability of auditory thresholds during the first 5 weeks after stapedectomy].
To assess repeatability of audiological test performed every week during the first month post-stapedectomy, audiometry was performed to 21 patients with otosclerosis (mean age 37.8 years, S.D. 9.29), every week, during the 2 weeks prior to stapedectomy and during the first 5 weeks and at week 12 after stapedectomy. Repeatability of the audiological test was evaluated comparing the difference between the audiological evaluations performed before the surgery and the difference between each consecutive pair of audiological evaluations after the surgery, using Bland & Altman method and ANOVA, allowing for 5% of significance. Before the surgery, audiological thresholds, using head phones, were repeatable for low (125-500 Hz), mid (500-2000 Hz) and high (2000-8000 Hz) frequencies in 95% of the patients. After the surgery, repeatability of air conduction thresholds for the low frequency band was evident from the 2nd week, for the mid frequency band was evident from the 3rd week and for the high frequency band from the 4th week. The gain observed at week 5 after surgery was similar to the gain observed at week 12. In conclusion, in this study, stable air conduction auditory thresholds were obtained during the first month after stapedectomy.
Adult↗
Age effects in the human middle ear: wideband acoustical measures.
Studies that have examined age effects in the human middle ear using either admittance measures at 220 or 660 Hz or multifrequency tympanometry from 200 to 2000 Hz have had conflicting results. Several studies have suggested an increase in admittance with age, while several others have suggested a decrease in admittance with age. A third group of studies found no significant age effect. This study examined 226 Hz tympanometry and wideband energy reflectance and impedance at ambient pressure in a group of 40 young adults and a group of 30 adults with age > or = 60 years. The groups did not differ in admittance measures of the middle ear at 226 Hz. However, significant age effects were found in wideband energy reflectance and impedance. In particular, in older adults there was a comparative decrease in reflectance from 800 to 2000 Hz but an increase near 4000 Hz. The results suggest a decrease in middle-ear stiffness with age. The findings of this study hold relevance for understanding the aging process in the auditory system, for the establishment of normative data for wideband energy reflectance, for the possibility of a conductive component to presbycusis, and for the interpretation of otoacoustic emission measurements.
Acoustic Impedance Tests↗
Hydroxylapatite blocks and particles as bone graft substitutes in orthognathic and reconstructive surgery.
A three-year clinical evaluation of 98 patients in whom dense hydroxylapatite in particle and block form had been placed in facial contour defects and osteotomy sites, and in cystic and reconstructive defects, alone or with autogenous bone, was conducted. The results indicate that the implants were effective in reducing operating time and potential for infection and relapse, as well as in reducing or eliminating the necessity of a donor site. The clinical response was excellent, and complications with both forms were minor, generally related to lack of initial fixation or failure to use autogenous bone in specific situations.
Bone Transplantation↗
Endolymphatic sac tumor: a case report.
Papillary tumors of the temporal bone are aggressive neoplasms which may occur sporadically or as a part of von Hippel-Lindau disease. The term 'endolymphatic sac tumor' identifies the origin of these rare tumors. The clinical manifestations are sensorineural hearing loss, facial paralysis, cerebellar disorders and vertigo. The tumor is locally invasive, destructive and hypervascular exhibiting consistent imaging and histopathologic features. The treatment of choice is the total removal of the lesion although complete excision of the advanced lesion is nearly impossible due to the anatomic complexity of the endolymphatic sac and distinct patterns of extension. We present a 50-year-old male patient with endolymphatic sac tumor with left sided sensorineural hearing loss and review the literature.
Audiometry, Pure-Tone↗
Effects of intensive and moderate cellular phone use on hearing function.
The purpose of this study is to investigate the effects of radiation emitted by mobile phones on the hearing of users. The study was carried out on three groups: 1) 20 men who have used a cellular phone frequently and spoken approximately 2 h per day for four years; 2) 20 men who have used a cellular phone for 10-20 min per day for four years; and 3) 20 healthy men who have never used a cellular phone (the control group). Brainstem evoked response audiometric (BERA) and pure tone audiometric (PTA) methods were used to measure the effects of exposure on hearing function of the subjects. In BERA measurements, I-III, III-V, and I-V interpeak latencies were evaluated. Interpeak latency of subjects in two experimental groups was compared to that of subjects in the control group. The BERA results showed no differences among the groups (p > 0.05). In PTA measurements, detection thresholds at 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, and 8000 Hz frequencies were measured in all three groups. No differences were observed between moderate mobile phone users (10-20 min. per day) and control subjects. However, detection thresholds in those who talked approximately 2 h per day were found to be higher than those in either moderate users or control subjects. Differences at 4000 Hz for both bone and air conduction for right ears, and 500 Hz, and 4000 Hz bone and air conduction for left ears were significant for mean hearing threshold. This study shows that a higher degree of hearing loss is associated with long-term exposure to electromagnetic (EM) field generated by cellular phones.
Adult↗
Sesamoid bone in the stapediovestibular articulation with conductive hearing loss.
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Aged, 80 and over↗
[The estimation of hearing threshold for high frequencies in children from the Upper Silesia].
Study was carried out in frequency range 8-18 kHz with audiometer AS 10 HF. Lack of internationally accepted reference value of the hearing threshold of air conduction at extended frequency range resulted in own evaluation of the audiometric zero point for air conduction at the range 8-18 kHz in "otologically healthy" subjects younger than 20 years. They were divided into subgroup A and B according to age. Investigation of the threshold values for air conduction at extended range of high frequencies were base for evaluation of the audiometric zero value for the used equipment.
Adolescent↗
Modified Exeter technique in revision hip surgery: does distal fixation of the stem affect allograft transformation?
Promising results have made the Exeter technique a valuable alternative in hip replacement revision. However, even with this technique, subsidence remains a difficult problem because it may lead to additional revision if it is not mild and self-limited. We propose a technical modification that achieves primary stability by cementing the distal portion of the stem directly to the host bone. We conducted a prospective study on 45 hips. After an average of 46 (range, 18-72) months of follow-up monitoring, no hips required or underwent revision for aseptic loosening of the prosthesis. Four stems subsided <5 mm. In each case, distal cementation was only fair, so implant strength was decreased. Allograft transformation occurred in 36 hips and was associated with host bone remodeling in 11. This technical modification appears to be reliable, as satisfactory distal cementation was achieved in 41 hips (91%), and the modification did not interfere with allograft transformation.
Adult↗
Cochlear changes in chronic otitis media.
OBJECTIVES/HYPOTHESIS: The objective was to describe the morphological changes in the cochlea in chronic otitis media. STUDY DESIGN: Retrospective human temporal bone analysis. METHODS: Fifteen temporal bones with unilateral chronic otitis media were selected and compared with contralateral normal temporal bones. Standard cytocochleograms and spiral ganglion cell reconstructions were performed on all temporal bones. Spiral ligament was divided into four segments according to the locations of different types of fibrocytes. The average loss of fibrocytes in each segment was estimated. Morphometric measurements of areas of stria vascularis and spiral ligament were made in all turns of the cochlea on mid modiolar sections. RESULTS: Loss of outer and inner hair cells was common in the basal turn of the cochlea in temporal bones with chronic otitis media compared with control ears. There was no difference in the number of spiral ganglion cells in the chronic otitis media and contralateral ears. The areas of stria vascularis and spiral ligament in the basal turn decreased significantly in the ears with chronic otitis media compared with control ears. There were no significant differences between the ears with chronic otitis media and the contralateral ears for any of the regions characterized by the presence of types I-IV fibrocytes. CONCLUSION: The results of the study are consistent with the hypothesis that chronic otitis media causes cochlear disease.
Adolescent↗
[Ratio of different sound conducting ways and dynamics of Weber's experiment in health and disease].
A complex of audiometric tests in ear-phones and in the free acoustic field and using hearing aids was made in normally hearing individuals and in patients with asymmetric secondary neurosensory hypoacusis in the presence of adhesive otitis media and tubal otitis. There were various frequency ranges in which the dynamics of Weber's experiment differently varied with the strength of a signal and with the type of an abnormality. The combined signal sending along the bone and air to one ear was shown to be of diagnostic value. There was a need for individually selecting characteristics of a hearing apparatus irrespective audiometric findings.
Bone Conduction↗
Detecting and remediating external meatal collapse during audiologic assessment.
We present a case study in which the jaw/mouth-open procedure during air-conduction testing is employed to both detect and remediate external auditory meatal collapse. A prospective investigation was also conducted to compare the efficacy of the proposed jaw/mouth-open procedure with that of the traditional insert receivers in remediating meatal collapse during audiologic assessment. Meatal collapse was present in 6 of the 136 subjects evaluated. In these 6 subjects, the air-conduction thresholds under supra-aural headphones in the jaw/mouth-open condition were similar to those under insert receivers. We discuss the implications of this finding in clinical settings where insert receivers are not available.
Adult↗
The effect of rapid maxillary expansion on conductive hearing loss.
The effects of rapid maxillary expansion (RME) on conductive hearing loss were investigated in 14 subjects (11 females and 3 males). The subjects ranged in age from 10 years 4 months to 16 years 9 months (mean age 12 years 11 months +/- 1 year 9 months) and had narrow maxillary arches and conductive hearing loss. Hearing levels were determined by means of pure-tone audiometric records. Three records were taken for each subject. The first was taken before RME, the second after sufficient midpalatal suture opening was achieved (mean = 15 days), and the third after the retention period (mean = 4.5 months). All the audiometric records were assessed by an otolaryngologist. Changes in both hearing level and air-bone gap were investigated by means of analysis of variance. It has been determined that hearing improved at a statistically significant level (P < 0.05) after the active treatment period, but that the improvement reversed at the end of the retention period. Five patients experienced significant and stable hearing improvement over the duration of this study.
Adolescent↗