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Congenital middle ear cholesteatomas in children: our experience in 34 cases.

OBJECTIVES: To evaluate clinical data, extensions, residual disease rate, and functional results in cases of congenital cholesteatoma in pediatric patients compared with cases of acquired forms. STUDY DESIGN AND SETTING: In a retrospective study conducted at a single tertiary care center over a decade, 34 congenital cholesteatomas (mean patient age, 6.6 years) isolated from a series of 215 cholesteatomas in children were treated surgically and followed up for an average of 83 months. Surgical treatment consisted of the closed technique (CT), open technique tympanoplasty in CT [TOT], radical mastoidectomy (RM), or Rambo's technique. The main outcome measures were surgical findings, residual lesion rate, and hearing assessment. RESULTS: The first surgical procedure was CT in 85.3%, TOT in 8.8%, RM in 2.9%, and Rambo's technique in 2.9% of patients. Two, 3, and 4 operations were necessary in 76.5%, 11.4%, and 11.4% of children, respectively. Residual lesions were observed in 34.6% of those multi-operated patients (7 CT and 2 TOT), 24.1% in those treated with CT, and 29.2% in those treated with CT with a planned second look. Mean postoperative pure tone average and air-bone gap were 26 and 21 dB, respectively. A speech reception threshold of less than 30 dB HL was achieved in 66% of patients. A total of 26 ossiculoplasties had to be performed (8 partial and 18 total); the mean postoperative air-bone gap was lower after the former (15 dB) than after the latter (22 dB). A high-frequency pure-tone hearing loss of more than 10 dB was uncommon (5.8%). Unsurprisingly, the residual lesion rate seems to be higher for congenital than for acquired cholesteatomas, but hearing results are significantly better. CONCLUSION: In most cases, staged CT appears to be the best technique to treat these lesions, which often develop in a well-pneumatized mastoid.

Acoustic Impedance Tests↗

Bone-constructing cells from ethmoid bone may have multilineage differentiation potential: preliminary report.

OBJECTIVE: In order to investigate multilineage differentiation in human cultured cells from ethmoid bone, we conducted a morphological study to examine adipogenic and chondrogenic differentiation. MATERIAL AND METHODS: After reaching confluence, cells underwent terminal adipogenic differentiation by treatment with 100 microM indomethacin, 0.5 mM 1-methyl-3-isobutylxanthine, 1 microM dexamethasone (DEX), 10 microg/ml insulin and 0.3% dimethylsulfoxide in a medium supplemented with 10% fetal bovine serum. Chondrogenic differentiation was attempted by centrifuging a pelleted micromass using transforming growth factor-beta3 (TGF-beta3), DEX, ascorbic acid (AA), pyruvate acid, proline, glucose and (ITS)-plus. RESULTS: The cultured cells displayed adipocyte but not chondrogenic lineage under these conditions. Considering the possibility that some differentiation potential may be lost with in vitro culture but maintained using another chondrogenic differentiation medium containing TGF-beta1, it is possible that cultured cells may have multilineage potential, including chondrogenic differentiation ability. CONCLUSIONS: These morphological abilities of human cultured cells may indicate the possibility of the existence of mesenchymal stem cells in sinus bone. If mesenchymal stem cells exist in ethmoid bone, they may play an important role in future research on the regulation mechanisms of human bone tissue.

Adipocytes↗

Auditory brainstem responses in a case of high-frequency conductive hearing loss.

Click-evoked auditory brainstem responses were measured in a patient with high-frequency conductive hearing loss. As is typical in cases of conductive hearing loss, Wave I latency was prolonged beyond normal limits. Interpeak latency differences were just below the lower limits of the normal range. The Wave V latency-intensity function, however, was abnormally steep. This pattern is explained by the hypothesis that the slope of the latency-intensity function is determined principally by the configuration of the hearing loss. In cases of high-frequency hearing loss (regardless of the etiology), the response may be dominated by more apical regions of the cochlea at lower intensities and thus have a longer latency.

Audiometry↗

Giant cell tumor of long bone: a Canadian Sarcoma Group study.

A multicentric retrospective study of giant cell tumor of bone was conducted among Canadian surgeons. The hypothesis was that no differences would be found in health status, function, or recurrence rate irrespective to the nature of filling material or adjuvant used in patients treated with curettage. One hundred eighty-six cases were collected. There were 96 females and 90 males. The mean age of the patients was 36 years (range, 14-72 years), the minimum followup was 24 months, and the median followup was 60 months. Sixty-two percent of the tumors involved the knee region. One hundred fifty-eight were primary tumors and 28 were recurrences. Campanacci grading was as follows: Grade 1, seven patients; Grade 2, 100 patients; Grade 3, 76 patients; and unknown in three patients. Fifty-six patients had a pathologic fracture. Resection was done in 38 patients and 148 patients had curettage. The latter was supplemented with high speed burring in 135 patients, cement in 64 patients, various combinations of autograft or allograft bone in 61 patients, phenol in 37 patients, and liquid nitrogen in 10 patients. Structural allografts were used in 25 patients. The overall recurrence rate was 17%, 18% after curettage, and 16% after resection. Patients with primary tumors treated with curettage had a 10% recurrence rate. For recurrent lesions treated by curettage, the recurrence rate was 35%. The nature of the filling material used or the type of adjuvant method used or any combination of both failed to show any statistical impact on the recurrence risk. The results from the Musculoskeletal Tumor Society rating from 1987 were significantly lower in patients who sustained a displaced fracture. Results from the bodily pain section of the Short Form-36 also were found to be lower when a pathologic fracture was present. Results from the Musculoskeletal Tumor Society Rating 1987, the Short Form-36, and the Toronto Extremity Salvage Score did not show differences when either cement or bone graft were used after curettage.

Adolescent↗

Middle ear involvement in children with chronic rheumatoid juvenile arthritis.

In a selected sample of patients affected by juvenile rheumatoid arthritis (JRA) little is known about middle ear involvement, even though many synovial joints are affected. Multifrequency tympanometry was used to measure admittance, conductance, susceptance and phase angle at different probe frequencies and resonant frequencies. In all, 35 children with JRA and a control group (30 children) were studied. Findings showed that mean resonant frequency values in all children with JRA were greater than in the control children. The multifrequency tympanometry parameters measured in acute JRA subjects are not different from parameters of remission JRA subjects except for a change in the phase angle. The changes found are due to involvement of the incudomalleolar and incudostapedial joints.

Acoustic Impedance Tests↗

The earplug procedure.

In the measurement of hearing, a masking dilemma is a situation in which it is not possible to use masking to determine if the signal is crossing the head and activating the opposite cochlea. A nonmasking procedure, called the earplug procedure, was developed to rule out crossover for air-conducted signals in patients with a masking dilemma. In the procedure, an earplug is inserted in the suspect ear in an attempt to increase the loss in that ear. If the loss is increased significantly, then thresholds were obtained from the test ear and crossover is ruled out. If there was no significant threshold shift with the earplug, crossover is not ruled out and the uncertainty remains. Threshold shift criteria were developed for five test frequencies and for single test frequencies. The procedure correctly rules out crossover for a majority of unmaskable ears.

Adolescent↗

[Myringoplasty in children: a comparison with an adult population].

The indications for myringoplasty in children has always been a controversial subject since many authors feel the high frequency of the phlogistic auricular processes in children constitute an unfavorable prognostic factor to success of the procedure. The authors present the results obtained in 23 patients under 17 years of age who had undergone myringoplasty for simple perforation of the tympanum. In cases of posterior and inferior perforations, surgery was performed using the underlay technique and a transmeatal approach; in all other cases the overlay technique was used with a retroauricular approach. An average 30 month follow-up (range 12-55 months) revealed new perforations in only 2 cases (9%). From the functional point of view the average air/bone conduction gap was reduced to 10 dB. As a control, the results were compared to those obtained in 150 patients over 16 years of age, again affected by simple perforation of the tympanic membrane and treated by myringoplasty using the same methods. In the adults, 22 new perforations were found (15%) while the functional results were analogous to those obtained in the children group. In this light, it can be asserted that myringoplasty can be considered a safe procedure to be used in children and it does not appear essential to wait until they have finished growing before performing this procedure.

Adolescent↗

Reconstruction of the ossicular chain using a multistrand wire spring prosthesis.

A 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.

Bone Conduction↗

Regulation of cytoplasmic pH in osteoclasts. Contribution of proton pumps and a proton-selective conductance.

Osteoclasts resorb bone by secreting protons into an extracellular resorption zone through vacuolar-type proton pumps located in the ruffled border. The present study was undertaken to evaluate whether proton pumps also contribute to intracellular pH (pHi) regulation. Fluorescence imaging and photometry, and electrophysiological methods were used to characterize the mechanisms of pH regulation in isolated rabbit osteoclasts. The fluorescence of single osteoclasts cultured on glass coverslips and loaded with a pH-sensitive indicator was measured in nominally HCO(3-)-free solutions. When suspended in Na(+)-rich medium, the cells recovered from an acute acid load primarily by means of an amiloride-sensitive Na+/H+ antiporter. However, rapid recovery was also observed in Na(+)-free medium when K+ was used as the substitute. Bafilomycin-sensitive, vacuolar-type pumps were found to contribute marginally to pH regulation and no evidence was found for K+/H+ exchange. In contrast, pHi recovery in high K+ medium was largely attributed to a Zn(2+)-sensitive proton conductive pathway. The properties of this conductance were analyzed by patch-clamping osteoclasts in the whole-cell configuration. Depolarizing pulses induced a slowly developing outward current and a concomitant cytosolic alkalinization. Determination of the reversal potential during ion substitution experiments indicated that the current was due to H+ (equivalent) translocation across the membrane. The H+ current was greatly stimulated by reducing pHi, consistent with a homeostatic role of the conductive pathway during intracellular acidosis. These results suggest that vacuolar-type proton pumps contribute minimally to the recovery of cytoplasmic pH from intracellular acid loads. Instead, the data indicate the presence of a pH- and membrane potential-sensitive H+ conductance in the plasma membrane of osteoclasts. This conductance may contribute to translocation of charges and acid equivalents during bone resorption and/or generation of reactive oxygen intermediates by osteoclasts.

Animals↗

Surgery for congenital anomalies of the middle ear with mobile stapes.

In a series of 104 patients with congenital middle ear anomalies operated on from 1964 to 1986, 27 cases were found in which the stapes footplate was mobile and the conductive deafness was due to an anomaly in the remaining part of the ossicular chain. In 8 cases the middle ear anomaly was caused by discontinuity of the ossicular chain owing to congenital malformation. In the other 19 ears, epitympanic fixation of the ossicular chain was observed, whether or not in combination with malformation of the stapes, incus or malleus. Ossicular chain reconstruction produced an improvement of at least 15 dB in 6 of the first 8 cases with discontinuity of the ossicular chain. The mean gain was 31 dB. Epitympanotomy with exposure of the fixed ossicle and if necessary ossicular chain reconstruction led to an improvement of at least 15 dB in 12 of the 19 ears, with a mean gain of 28 dB.

Adolescent↗

An analysis of the results of myringoplasty in children.

An analysis of the results of 100 temporalis fascia underlay myringoplasties in children between the ages of 2-17 years is presented. The follow-up period in this retrospective review was from 6 to 24 months. There was no statistically significant correlation between the age of patient, a history of previous ear surgery, previous general anaesthesia, previous adenotonsillar surgery, preoperative otorrhoea, impaired eustachian tubal function, individual surgeon performing the surgery, size of perforation or operative technique and the outcome of the surgery with respect to graft take rate. The overall graft take rate was 75.3% of the 93 patients that returned for follow-up. The seniority of the surgeon and by implication the degree of operative experience of the surgeon is found to be significantly correlated with the graft take rate (P < 0.05). On audiometric testing, the mean pre-operative air conduction threshold improved significantly (P < 0.0001) from 32.0 dBHL (S.D. 11.22) to 20.18 dBHL (S.D. 15.54) while the speech reception threshold improved from a mean of 25.34 dBHL (S.D. 12.88) to 18.79 (S.D. 15.5) (P < 0.0005). Although not statistically significant, patients under the age of 8 years were found to have a low graft take rate (56%) when compared to the mean. The audiometric results in this age group were comparable to the rest of the group. The findings in this study suggest that myringoplasty is a beneficial procedure in the pediatric population in the hands of a skilled and experienced surgeon. The learning curve seen in the surgeons in this study suggests that suitable cases for junior surgeons should be carefully selected.

Adolescent↗

SISI test and adaptation. II. Subjects with conductive hearing defects.

The effect of adaptation of the ear on the SISI test was studied at 500 Hz and 2000 Hz in 43 patients with chronic otitis and in 20 patients with otosclerosis. The mean adaptation was slightly over 10 dB, except in the otosclerosis group at 2000 Hz, for which the value was nearly 20 dB after continuous stimulation at 20 dB SL for 3 min. The mean SISI values ranged from 15% to 31% in the preadaptation tests and from 9% to 31% in the postadaptation tests. The scatter of the pre-and postadaptation SISI scores was wide, making statistical treatment of the results difficult. In the total material 22% of the values at 2000 Hz were positive according to Jerger's classification, and 32% were questionable. Adaptation slightly reduced the proportion of positive values, but there were changes towards both higher and lower levels in the cases of chronic otitis, while all the otosclerosis changes were diminutions.

Acoustic Stimulation↗

Quantitative three-phase bone scintigraphy in the evaluation of intravenous regional blockade treatment in patients with stage-I reflex sympathetic dystrophy of upper extremity.

OBJECTIVE: To investigate the role of quantitative three phase bone scintigraphy (QTPBS) in the evaluation of efficacy of intravenous regional blockade treatment in patients having reflex sympathetic dystrophy (RSD) of the upper extremity. MATERIAL AND METHODS: Twenty-six patients with stage-I RSD were focused on in this study. Patients were treated with physical therapy and intravenous (I.V.) regional blockade therapy consisting of dexamethasone and lidocaine. All patients were clinically evaluated before and 1 month after the completion of the therapy protocol. QTPBS was applied to patients before therapy and 1 month after the therapy. As a control group, 11 healthy subjects also underwent QTPBS. Perfusion, hyperemic and fixation indices were calculated from three-phase bone scintigraphy. RESULTS: All patients showed statistically significant clinical improvement after the therapy (p < 0.01). Pre-treatment, perfusion (1.67 +/- 0.63), hyperemic (1.44 +/- 0.48) and fixation (1.69 +/- 0.48) indices of patients were higher than those of healthy subjects (PI: 0.95 +/- 0.05, HI: 0.94 +/- 0.06, FI: 1.01 +/- 0.2) (p < 0.01) and all indices significantly decreased after the treatment (PI: 1.33 +/- 0.46, HI: 1.18 +/- 0.23, FI: 1.42 +/- 0.26) (p < 0.01). CONCLUSION: I.V. regional blockade therapy combined with corticosteroids is a simple, safe and effective method for the treatment of patients with stage-I RSD in the upper extremity. QTPBS is a valuable and objective method to evaluate the response to therapy and may be useful for staging of patients and predicting the response to therapy.

Adult↗

Adipose graft: an original option in myringoplasty.

OBJECTIVE: To describe the fat graft as a reconstructive material in myringoplasty. METHOD: In a review of 45 patients conducted between 1993 and 1999, the authors analyzed their patients' outcomes after having myringoplasties with fat graft. Median follow-up was 2.5 years (range, 6 mo-6 yr). RESULTS: We achieved a success rate of 91.1%. Different features of the patient and the tympanic perforation were studied to demonstrate their role in the quality of the surgical closing. A review of the literature was done to compare our results with the results of other series using this type of graft as well as with studies of the temporalis fascia as a graft material. CONCLUSION: The high reliability of the fat graft and the technical simplicity of this procedure in anterior perforations, especially with the use of intraoperative endoscopy, make it an attractive technique.

Adipose Tissue↗

Preschool otologic and audiologic screening.

A study of otologic and audiologic screening of preschool children including tympanometry, acoustic reflexes, and pure-tone screening was carried out at school sites. Subsequent pure-tone threshold tests and otolaryngologic examinations were carried out in a hospital setting. Complete data are available on 1,335 subjects, ages 3 through 5 years. Results are reported in comparison with those of an earlier Pittsburgh screening study. The results of the earlier study showed that loss of hearing sensitivity could not be predicted by the otologic findings, and conversely, the otologic findings could not be predicted by the air conduction thresholds. The results of the present study showed a contribution by tympanometry and acoustic reflexes. The results are evaluated in terms of screening effectiveness in these age groups. One of the recommendations combines an interpretation of certain large negative tympanometric peak pressures (TPP) along with the absence of acoustic reflexes to certain stimuli. The method is more efficient than other aspects of middle ear measurement or of pure-tone screeniing. The efficiency of each procedure is documented. Summary matrices are used to show the effectiveness of each test compared to all other tests in the identification of subjects with hearing or middle ear dysfunction. A protocol for screening evaluation and otologic referral is suggested to effect a balance between over-referral and correct identification.

Acoustic Impedance Tests↗

Auditory brainstem evoked potentials in evaluating the efficacy of surgical ventilation of the middle ear.

Conductive hearing loss in children is most commonly associated with Secretory otitis media (S.O.M.). Since auditory brainstem evoked potentials (ABEP) reflect conductive damage in prolonged peak latencies, the present study evaluated the efficacy of surgery for ventilating the middle ear, by comparing changes in peak latencies. These changes were compared in 4 groups of children (4-12 years old): children with S.O.M. in the past, who recovered as a result of conservative treatment; children with S.O.M. in the past, who had been operated on with insertion of ventilation tubes (V.T.); children with S.O.M. in the past, who had been operated on and who still had V.T. at the time of study, and a control group with healthy ears. In all, 183 ears were tested. The results indicate that there is no significant audiometric and electrophysiological difference between the groups who recovered with or without V.T.

Audiometry, Evoked Response↗

Transcranial conduction of acoustic-reflex-eliciting signals.

Conduction of a broad-band signal from a supra-aural earphone to an acoustic-immittance instrument coupled to the contralateral ear canal was studied using three commercial immittance instruments. Results indicated that portions of the broad-band signal reached the contralateral ear canal at presentation levels of 100-110 dB SPL. At levels as low as 100 dB SPL, the signal was detected by at least one of the acoustic-immittance instruments. At higher sound pressure levels the transmitted signal caused deflections of the acoustic-immittance meter similar to those associated with an acoustic-reflex response. However, these artifacts could be differentiated from acoustic-reflex responses in several respects and could be prevented by high-pass filtering of the broad-band test signal.

Acoustic Impedance Tests↗

Hearing loss in rheumatoid arthritis.

OBJECTIVE: The objective of this study was to evaluate whether patients with rheumatoid arthritis (RA) are more likely to have subclinical hearing loss compared with persons without RA. METHODS: This is a case-control cross-sectional study of 29 patients with RA with disease duration greater than 5 years. Five males and five females were recruited into each decade category (age 40-49, 50-59, and 60-69). These cases were matched in a 1:1 ratio by sex and age to 30 control subjects. A comprehensive set of audiometric and disease severity assessments were performed. RESULTS: Seventeen (59%) of 29 patients with RA had abnormal hearing for at least one frequency (four in one ear, 13 in two ears) by audiometry as did 14 (47%) of 30 control subjects (five in one ear, nine in two ears). The percentage of patients with hearing loss (% RA vs. % control subjects) was: 45% versus 40% sensorineural, 10% versus 7% conductive, and 3% versus 0% mixed hearing loss. In RA versus control subjects, acoustic reflex threshold was abnormal in 17% versus 7%; speech reception threshold was abnormal in 10% versus 3%. Tympanometry and otoacoustic emission findings were similar in both groups. Word recognition did not differ between patients with RA and control subjects. In patients with RA/control subjects, hearing handicap, dizziness, and health assessment questionnaires were abnormal in 28%/7%, 14%/3%, and 72%/7%, respectively. CONCLUSION: There was no difference found in objective audiometric measurements in patients with RA compared with non-RA control subjects. Subjectively patients with RA were more likely to perceive themselves as having hearing disturbances, which may be related to overall disease related functional impairment.

Acoustic Impedance Tests↗