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Bernard Fraysse

Publications and source records attributed to Bernard Fraysse.

15 recordsLinked to original sources
PubMed2006

The size of the cochlea and predictions of insertion depth angles for cochlear implant electrodes.

AIMS: To establish normative data on the size of the basal turn of the cochlea using high-resolution computed tomography of the temporal bone in adults and children. To determine whether final insertion depth angle for a perimodiolar cochlear implant electrode varies according to cochlear size. METHODS: Forty-two patients screened for cochlear anomaly using computed tomography were randomly selected from patients with otologic disease. Reconstruction of the full basal turn was performed for both ears using a 1.0-mm layer, minimum intensity projection. The largest distance from the round window to the lateral wall (distance A) and the perpendicular distance (B) were measured. Distances were averaged between ears for each individual. In addition, 15 patients were implanted with the Nucleus 24 Contour Advance electrode array using a linear insertion depth of either 17 mm (n = 9) or 19 mm (n = 6). Postoperative X-rays were analyzed using the method of Xu et al. [Am J Otol 2000;21:49-56] to obtain the insertion depth angles for individual electrodes. RESULTS: Mean distance A was 9.23 mm (SD = 0.53, range 7.9-10.8 mm). Perpendicular distance B was significantly correlated with distance A (r2 = 0.57, p < 0.001). The mean difference in insertion depth angle between the 17 and 19 mm groups was 80 degrees . A statistically significant correlation (r2 = 0.51) was found between distance A and the insertion depth angle for the 17 mm group. CONCLUSIONS: The cochlear size measure distance A was repeatable to within the resolution of the high-resolution computed tomography image data. The basal turn of the normally formed cochlea is variable in size. These variations in size would produce >5.0 mm variation in the length of the lateral wall to the point consistent with an insertion depth angle of 360 degrees . Cochlear size influenced final insertion depth angles obtained for the perimodiolar Nucleus 24 Contour Advance electrode.

Adolescent↗
PubMed2006

Combined electroacoustic stimulation in conventional candidates for cochlear implantation.

OBJECTIVE: To report on combined ipsilateral electrical and acoustic stimulation in a subset of conventional candidates for cochlear implantation where preoperative pure tone thresholds were </=60 dB HL for 250 and 500 Hz. METHODS: Subjects were 10 adults implanted with the Nucleus 24 Contour Advance perimodiolar electrode array. Soft surgical procedures were strictly observed: </=1.5-mm cochleostomy hole placed anterior and inferior to the round window, a Healon bubble placed over the opening to prevent entry of foreign bodies, and no suction applied. The electrode array was inserted 17 mm to the first marker rib using the recommended 'advance-off-stylet' technique. Pure tone hearing threshold levels were recorded pre-, and postoperatively at 1-2 and 6-12 months. Speech recognition was tested for cochlear implant (CI) alone and combined with ipsilateral hearing aid for 7 subjects who retained significant residual hearing in the implanted ear at 1-2 months after operation. RESULTS: There were 3/10 cases where 1-2 months after operation low-frequency responses were considered vibrotactile only (>85-110 dB HL, 250-500 Hz). In the remaining 7 cases, residual hearing was maintained up to at least 6 months after operation with minor changes. Insertion depth angles in these cases ranged from 285 to 420 degrees . For these subjects, the mean preoperative score for words presented at 65 dB SPL was 22%. Mean postoperative scores were 56% for CI alone, and 68% for CI plus ipsilateral hearing aid (p < 0.05, paired t). For sentences presented in multitalker babble noise at 5 dB SNR, mean scores were 61% CI alone, and 75% CI+IpsiHA (p < 0.01, paired t). CONCLUSIONS: Hearing was conserved during surgery and over time in 70% of conventional candidates implanted with the Nucleus 24 Contour Advance CI who had significant levels of preoperative low-frequency residual hearing (</=60 dB HL). These conventional candidates for CI also benefited from improved speech recognition in noise when using combined ipsilateral electrical and acoustic stimulation.

Acoustic Stimulation↗
PubMed2006

Residual hearing conservation and electroacoustic stimulation with the nucleus 24 contour advance cochlear implant.

OBJECTIVE: To assess the conservation of residual hearing in recipients of the Nucleus 24 Contour Advance cochlear implant (CI) and the benefits of combined electrical and acoustic stimulation. STUDY DESIGN: Prospective multicenter study. SETTING: CI clinics in Western Europe. PATIENTS: Adult candidates for conventional cochlear implantation with a minimum preoperative word recognition score of 10% in the ear to be implanted. INTERVENTION: "Soft-surgery" protocol, including a 1- to 1.2-mm anterior and inferior cochleostomy hole with the electrode array, inserted 17 mm using the "advance-off-stylet" technique. Patients with postoperative pure-tone hearing threshold levels (HTLs) of 80 dB hearing loss or less at 125 and 250 Hz and 90 dB hearing loss or less at 500 Hz were refitted with an in-the-ear hearing aid for combined ipsilateral electrical and acoustic (El-Ac) stimulation. MAIN OUTCOME MEASURES: A questionnaire to collect information regarding surgery. Pure-tone HTLs measured at intervals. Word recognition tested in quiet and sentence recognition tested in noise at 10 and 5 dB signal-to-noise ratio (SNR). HEARING CONSERVATION RESULTS: HTL data were available for 27 patients. HTLs were conserved within 20 dB of preoperative levels for 33, 26, and 19% of patients for 125, 250, and 500 Hz, respectively. However, the recommended soft-surgery protocol was strictly followed in only 12 of 27 patients. For these 12 patients, hearing thresholds were conserved within 20 dB for 50, 50, and 33% of patients. Median threshold increases were 40 dB (range, 250-500 Hz) for the whole group and 23 dB for the strict surgery group. Ten patients retained sufficient HTLs to enter the El-Ac user group. SPEECH RECOGNITION RESULTS: Group mean recognition scores for nine El-Ac users for words presented at 65 dB sound pressure level were 45% for CI alone and 55% for CI + ipsilateral hearing aid (p < 0.05, paired t). For sentences presented in noise at 5 dB SNR, mean word scores were 46% CI alone and 56% CI + ipsilateral hearing aid (p < 0.01, paired t). CONCLUSION: Hearing was conserved for conventional candidates for cochlear implantation where the recommended soft-surgery protocol was strictly adhered. Combined ipsilateral electrical and acoustic stimulation provided considerable benefits for speech recognition in noise, equivalent to between 3 and 5 dB SNR, compared with CI alone.

Acoustic Stimulation↗
PubMed2005

Preservation of residual hearing with cochlear implantation: how and why.

CONCLUSIONS: Hearing may be conserved in adults after implantation with the Nucleus Contour Advance perimodiolar electrode array. The degree of hearing preservation and the maximum insertion depth of the electrode array can vary considerably despite a defined surgical protocol. Residual hearing combined with electrical stimulation in the same ear can provide additional benefits even for conventional candidates for cochlear implantation. OBJECTIVES: We present preliminary results from a prospective multicentre study investigating the conservation of residual hearing after implantation with a standard-length Nucleus Contour Advance perimodiolar electrode array and the benefits of combined electrical and acoustic stimulation. MATERIAL AND METHODS: The subjects were 12 adult candidates for cochlear implantation recruited according to national selection criteria. A "soft" surgery protocol was defined, as follows: 1-1.2-mm cochleostomy hole anterior and inferior to the round window; Nucleus Contour Advance electrode array inserted using the "Advance-off-stylet" technique; and insertion depth controlled by means of three square marker ribs left outside the cochleostomy hole. These procedures had been shown to reduce insertion forces in temporal bone preparations. Variations in surgical techniques were monitored using a questionnaire. Pure-tone thresholds were measured pre- and postoperatively. Patients who still retained thresholds <90 dB HL for frequencies up to 500 Hz were re-fitted with an in-the-ear (ITE) hearing aid. Word recognition was tested in quiet and sentence perception in noise for the cochlear implant alone and in combination with an ipsilateral hearing aid. RESULTS: Hearing threshold level data were available for 12 patients recruited from 6 of the centres. Median increases in hearing threshold levels were 23, 27 and 33 dB for the frequencies 125, 250 and 500 Hz, respectively. These median increases include the data for two patients who had total loss of residual hearing due to difficulties encountered during surgery. "Cochlear view" X-ray images indicated that the depth of insertion varied between 300 and 430 degrees, despite modest variations in the length of the electrode inserted (17-19 mm). The insertion angle had some influence on the preservation of residual hearing at frequencies of 250-500 Hz. Six of the 12 patients retained sufficient hearing for effective use of an ipsilateral ITE hearing aid (< or = 80 dB HL at 125 and 250 Hz; < or = 90 dB HL at 500 Hz). Word recognition scores in quiet were improved from 10% to 30% with the cochlear implant plus ipsilateral hearing aid in 3 patients who had at least 3 months postoperative experience. Signal:noise ratio thresholds for sentence recognition were improved by up to 3 dB. Patients reported that they experienced greatly improved sound quality and preferred to use the two devices together.

Adult↗
PubMed2005

Comparison between intraoperative observations and electromyographic monitoring data for facial nerve outcome after vestibular schwannoma surgery.

A four-channel device may enhance the sensitivity of electromyography (EMG). Determination of stimulation thresholds (STs) below 0.05 mA improves facial prognostic information after vestibular schwannoma (VS) surgery. To compare intraoperative observations with electromyographic data for predicting the immediate facial function outcome after VS surgery.A total of 111 VS patients operated on and intraoperatively monitored using four-channel facial EMG between October 2002 and September 2003 were included in this multicentre, prospective study. Mascular activity detection was performed in the frontal, orbicularis oculi, orbicularis oris and platysma muscles. Intraoperative observations were made concerning adhesion and nerve stretch, and facial function was graded (House-Brackmann classification) at postoperative Days 1 and 8.Facial function at postoperative Days 1 and 8 was related to the intraoperative nerve STs at the brainstem and in the adhesion zone (range 0.01-3 mA for a response > 100 microV). At postoperative Day 8, good facial function (Grades 1 or 2) was observed in 93% of cases for STs in the adhesion zone of 0.01-0.04 mA, 85% for STs of 0.05-0.3 mA and 79% for STs > 0.3 mA. These STs were related to the degree of tumor adhesion and not to the nerve stretch. The maximal EMG response was detected in the frontal or platysma muscles in 26% of cases, and in the orbicularis oris and orbicularis oculi muscles in 74%.

Adolescent↗
PubMed2005

Binaurality in middle ear implant recipients using contralateral digital hearing AIDS.

OBJECTIVE: For some patients, conventional hearing aids might have disadvantages that clearly limit the benefit of using them. The middle ear implant, Vibrant Soundbridge hearing prosthesis offers an approach to help such patients. Our study's objective was to identify the binaurality in a well-fitted digital hearing aid worn in the contralateral ear in recipients experienced with use of the Vibrant Soundbridge middle ear implant device. STUDY DESIGN: In a prospective study, warble-tone thresholds and stereophony were evaluated for the following conditions: (1) binaural unaided-with the middle ear implant inactive and the behind-the-ear hearing aid removed; (2) middle ear implant alone-middle ear implant active, behind-the-ear hearing aid removed; (3) middle ear implant plus behind-the-ear omnidirectional-middle ear implant active, behind-the-ear active; and (4) behind-the-ear omnidirectional alone-middle ear implant inactive, behind-the-ear omnidirectional active. Behind-the-ear omnidirectional and behind-the-ear is defined as the behind-the-ear active in the omnidirectional or directional response, respectively. Behind-the-ear is a contralateral digital hearing aid to the middle ear implant. Benefits such as improved sound detection, speech perception in quiet and in noise, and sound quality were investigated. The evaluation of subjective hearing benefit was based on the Abbreviated Profile of Hearing Aid Benefit (APHAB) test. Paired t tests (subject) were used to analyze the differences between mean thresholds for the different test conditions. SETTING: Tertiary referral center. PATIENTS: Eight adults (aged 45-68 yr) had undergone implantation with a single Vibrant Soundbridge at least 12 months before starting the study. These eight subjects presented no contraindication for contralateral hearing aid use. Patients were fitted 5 weeks before testing with a Siemens Signia digital behind-the-ear hearing aid in the side contralateral to the Vibrant Soundbridge. RESULTS: Five weeks after use of the contralateral hearing aid together with the middle ear implant, mean differences in warble-tone thresholds between Conditions 2 and 3 and between Conditions 3 and 4 were both statistically significant. The mean differences in speech reception thresholds were in line with the mean differences in average warble-tone thresholds. The mean speech reception threshold for the middle ear implant plus behind-the-ear omnidirectional condition was slightly worse (3 dB) than that for the middle ear implant alone condition; however, this difference was not statistically significant. Whereas speech reception threshold difference between Condition 1 and Condition 4 was not statistically significant (60 dB and 61 dB, respectively). The mean difference for the 0-degree azimuth alone was statistically significant (p < 0.05) for the conditions middle ear implant alone and middle ear implant plus behind-the-ear omnidirectional. The middle ear implant alone appears to give good sensitivity at 2 kHz for any direction. Increasing scores indicate greater percentages of problems. Percentages of problems were on average lower for the middle ear implant when used with the contralateral digital hearing aid based on the global score. CONCLUSION: The use of a middle ear implant Vibrant Soundbridge together with a contralateral digital hearing aid improved functional gain and speech perception thresholds in quiet, especially for the sound coming from the front of the patient. The use of a middle ear implant together with a contralateral digital hearing did not significantly improve hearing in noise.

Acoustic Stimulation↗
PubMed2004

Modeling the relationship between psychophysical perception and electrically evoked compound action potential threshold in young cochlear implant recipients: clinical implications for implant fitting.

OBJECTIVE: In cochlear implant recipients, the threshold of the electrically evoked compound action potential (ECAP) has been shown to correlate with the perceptual detection threshold and maximum comfortable loudness levels (respectively, T- and C-levels) used for implant programming. Our general objective was to model the relationship between ECAP threshold and T/C-levels by taking into account their relative changes within each subject. In particular, we were interested in investigating further the validity of ECAP threshold as a predictor of psychophysical levels, depending on intra-cochlear electrode location and time of testing (from 1 to 18 months post-implantation). METHODS: A total of 370 ECAP thresholds, measured in 49 children, using a Nucleus 24 cochlear implant, were compared with the corresponding T- and C-levels obtained at the same visit, for the same electrode. Response profiles for the whole group of patients were modeled across four test electrodes spaced equally along the electrode array from base towards apex. A linear regression model was constructed and the quality of the ECAP threshold-based predictions was assessed by testing for correlation between measured and predicted psychophysics. Comparison was made with a more simplistic model (described here as the 'parallel profiles method') stipulating, within each subject, a 1 microA increase in psychophysical levels for every 1 microA increase in ECAP threshold. RESULTS: Offset between ECAP threshold and psychophysics profiles was found to vary significantly along the electrode array for the T-, but not for the C-level. In contrast with the parallel profiles method, our regression model predicted, within each subject, an average increase of 0.23 microA (95% confidence interval: 0.18-0.28) in T-level for every 1 microA increase in ECAP threshold. This correction improved the quality of T-level prediction when our model was run using measured T-level and ECAP threshold from a reference electrode (r=0.77 vs. r=0.62). The shorter the distance between the electrode for which T-level was predicted and the one used as reference, the stronger the correlation between measured and predicted T-levels. In addition, poorer T-level predictions were obtained at the basal end of the array during the first 3 months post-implantation. In contrast to T-level, individual changes in C-level with ECAP threshold exhibited heterogeneous patterns across subjects so that no common coefficient could account for these changes. However, applying the parallel profiles method led to high-quality C-level prediction. CONCLUSIONS AND SIGNIFICANCE: The results suggest that covariation between ECAP thresholds and psychophysics plays a decisive role in the relationship of ECAP threshold with T-, but not with C-level. Therefore, our regression model and the parallel profiles method should both be used for predicting, respectively, the T- and the C-levels. Although the predictability of our regression model seems to be better for middle and apical electrodes, its utilization should be extended to basal electrodes after 6 months' implant use.

Action Potentials↗
PubMed2004

Speech perception and speech intelligibility in children after cochlear implantation.

OBJECTIVE: This study aimed to evaluate the long-term speech perception and speech intelligibility of congenitally and prelingually deaf children after cochlear implantation. It was a longitudinal study following 63 congenitally or prelingually deaf children up to 5 years after implantation. They each received a nucleus multichannel cochlear implant before they were 10 years old. METHODS: Perception is evaluated using the Test for the Evaluation of Voice Perception and Production (TEPP) and concerns closed- and open-set word and sentence perception without lip-reading. The intelligibility is classified according to the Speech Intelligibility Rating (SIR). The evaluations have been made every 3 months for 1 year, then at 18 months, 2 years, 3 years and 5 years after the cochlear implantation. RESULTS: After 5 years of implantation, the median percentage of closed-words speech perception (CSW) is 95.5%-93.67% for closed-sentence speech perception (CSS) and 76.3% for open-sentence speech perception (OSS); the median Speech Intelligibility Rating is 3.83. CONCLUSIONS: Congenitally and prelingually deaf children who receive cochlear implant before the age of 10 years develop speech perception and speech intelligibility abilities. The closed-set perception progresses quickly and seems to reaching a plateau at 5 years post implantation. The improvement of open-sentence perception is not significant until the first year post implantation. The speech intelligibility improves regularly the five first year post implantation.

Audiometry, Speech↗
PubMed2003

Music perception in adult cochlear implant recipients.

OBJECTIVE: To evaluate musical perception in adult cochlear implant (CI) recipients, i.e. perceptual accuracy for pitch, timbre, rhythmic patterns and song identification. MATERIAL AND METHODS: Twenty-nine adult patients were included in this transverse single-center study. Evaluative measures included tests assessing ability to discriminate pitch, rhythm and timbre and to identify nursery songs with and without verbal cues. Performance scores were correlated with duration of deafness, duration of implantation, speech discrimination and musical perception skills. RESULTS: A total of 38% of patients reported that they did not enjoy listening to music with their device and 86% presented lower scores of listening habits after implantation. We found positive correlations between musical background and pitch identification and identification of nursery songs played by piano. We also found positive correlations between speech discrimination and rhythm, timbre and identification of nursery songs with verbal cues. CONCLUSION: Trends in the patterns of correlation between speech and music perception suggest that music patterns are differentially accessible to CI users. New processing strategies may improve this.

Acoustic Stimulation↗
PubMed2003

Neurotological complications after radiosurgery versus conservative management in acoustic neuromas: a systematic review-based study.

OBJECTIVE: Treatment modalities for acoustic neuroma (AN) include surgery, observation and gamma-knife surgery. The aim of this study was to compare neurotological complications resulting from two treatment alternatives to microsurgery: radiosurgery and observation. MATERIAL AND METHODS: We conducted a systematic review of the literature dealing with radiosurgery for AN and compared the rate of neurotological complications in this population with that in a cohort of patients managed conservatively. RESULTS: We found that neurotological complications, namely facial hypoesthesia (p = 0.002), hearing loss (p < 0.05) and hydrocephalus (p = 0.02), were more frequently encountered after radiosurgery than with conservative management. In contrast, we found that the risk of growth of AN is significantly higher with conservative management and that the rate of stability of the tumor did not differ significantly between the two treatments. CONCLUSION: We prefer a conservative management regimen for patients who cannot be operated on for their AN. However, there are some difficulties inherent in this conservative management policy, namely non-compliance and difficulties in establishing the evolution of the tumor.

Facial Neuralgia↗
PubMed2003

A middle ear implant, the Symphonix Vibrant Soundbridge: retrospective study of the first 125 patients implanted in France.

OBJECTIVE: The Vibrant Soundbridge is an active semi-implantable middle ear implant for the rehabilitation of patients with a sensorineural hearing loss who are not able to derive adequate benefit from conventional hearing aids. A retrospective study was performed to assess the overall level of satisfaction of implanted patients and to investigate the potential determinants of postoperative success. STUDY DESIGN: A retrospective survey of audiological data from repeated measures and subjective data from self-assessment scales administered postoperatively was conducted to determine the degree of benefit and satisfaction for Vibrant Soundbridge implantees. SETTING: Twenty-one tertiary referral and teaching hospitals. SUBJECTS: The first 125 VSB implantees implanted in France between August 1997 and May 2001 were included in the study. RESULTS: No clinically significant change was observed for residual hearing postoperatively. Most patients (83%) reported they were either satisfied or very satisfied with the Vibrant Soundbridge. Analysis of correlation revealed a moderate correlation (Pearson coefficient r = 0.59) between the degree of benefit reported via the patient survey and the degree of benefit reported via the Glasgow Benefit Inventory. A moderate correlation (Pearson coefficient r = 0.66) was observed between speech comprehension scores in quiet for the preoperative unaided condition and the postoperative aided Vibrant Soundbridge condition. No correlation was observed between subjective reports of satisfaction postoperatively and performance on preoperative objective tests or patient characteristics. CONCLUSION: The results indicate a high level of satisfaction with the VSB as a treatment of sensorineural hearing impairment in patients with a wide range of characteristics. Preoperative scores for unaided speech comprehension tests in quiet may be a potential indicator of success on aided Vibrant Soundbridge speech comprehension tests postoperatively but do not reflect patient satisfaction with the device reported on self-assessment scales.

Adult↗
PubMed2002

Cochlear implantation in prelingually deafened children with residual hearing.

OBJECTIVE: The purpose of this study was to examine the speech perception skills of prelingually deafened French children with preoperative residual hearing who received multichannel cochlear implants. DESIGN: The design of the study incorporated a within-subject, repeated measures design for assessing speech perception skills. SETTING: Montpellier, Toulouse and Lyon Pediatric Cochlear Implant Centers. SUBJECTS: Seven prelingually deafened children demonstrating marginal benefit from conventional amplification prior to implantation with a Nucleus multichannel cochlear implant, served as subjects for the speech perception assessment (a speech recognition score less than 30% defines marginal benefit from acoustic amplification on open set materials). The mean age at implantation was 7 years, 9 months. OUTCOME MEASURES: Speech perception skills were assessed using open set materials and the MUSS and MAIS questionnaires. RESULTS: Open-set speech recognition averaged 21.4% before implantation, and 83.6% after 1 year's cochlear implant experience. All children demonstrated an open-set score over 60% after 12 months of CI use. MAIS test scores averaged 18.1/40 before implantation and 35.1/40 after 9 months of CI use. MUSS test scores averaged 24.4/40 before implantation and 34.1/40 after 9 months of CI use. CONCLUSIONS: Cochlear implantation should be considered for prelingually hearing impaired children demonstrating marginal benefit from hearing aids, with a speech recognition score less than 30% on open set materials, in order to improve their speech discrimination skills.

Audiometry↗
PubMed2002

Results from a European clinical investigation of the Nucleus multichannel auditory brainstem implant.

OBJECTIVE: This study was designed to investigate the perceptual benefits and potential risks of implanting the Nucleus(R) multichannel auditory brainstem implant. DESIGN: Between September 1992 and October 1997 a total of 27 subjects received a Nucleus 20- or 21-channel Auditory Brainstem Implant (ABI). All subjects involved in the trial had bilateral acoustic tumour as a result of neurofibromatosis type 2 (NF2) resulting in complete dysfunction of the VIIIth nerve. The study used each subject as their own control without a preoperative baseline because residual hearing, if existing, was destroyed at surgery by tumour removal. A battery of speech tests was conducted to evaluate each patient's performance and communication abilities. Tests were conducted, where possible, in the auditory-only, visual-only, and auditory-visual conditions at 3 days postoperatively (baseline), at 3-mo intervals for the first year and every 12 mo thereafter. A subjective performance questionnaire was administered together with an extensive neurological examination at each test interval. RESULTS: 27 subjects involved in this trial were successfully implanted with a Nucleus ABI. One subject died 2 days postoperatively due to a lung embolism unrelated to the device. Twenty-six subjects underwent device activation and all but one patient received auditory sensation at initial stimulation (96.2%). On average 8.6 (+/-4.2) of the available 21 electrodes were used in the patients' MAPs. Performance evaluation measures showed that the majority of users had access to auditory information such as environmental sound awareness together with stress and rhythm cues in speech that assist with lipreading. Although most subjects did not achieve any functional auditory-alone, open-set speech understanding, two subjects from this series (7.4%) did receive sufficient benefit to be able to use the ABI in conversation without lipreading. CONCLUSIONS: Although the medical risks and surgical complexity associated with ABI device implantation are far greater than those for a cochlear implant, the clinical results from this trial show that the Nucleus multichannel ABI is capable of providing a significant patient benefit over risk ratio for subjects suffering loss of hearing due to bilateral retrocochlear lesions.

Acoustic Stimulation↗
PubMed2002

Management of cholesterol granulomas of the petrous apex based on clinical and radiologic evaluation.

OBJECTIVE: The purpose of this study was to analyze the imaging characteristics of 12 cholesterol granulomas as a function of their clinical symptoms. The results of the different surgical approaches and the management of these lesions are discussed. STUDY DESIGN: Retrospective case review. SETTING: Five tertiary referral centers. PATIENTS: Twelve patients managed for a cholesterol granuloma of the petrous apex. INTERVENTIONS: All patients were evaluated via computed tomography and magnetic resonance imaging. Eight patients required surgical drainage: through a conservative approach in seven patients (infralabyrinthine, n = 5; infracochlear, n = 2) and a transotic approach in one patient. Clinical and radiologic follow-up without surgery was the mode of treatment for four patients. The mean follow-up period was 18 months for patients who underwent operations and ranged from 6 months to 10 years for patients without operations. RESULTS: Four patterns of clinical symptoms were noted: retrocochlear signs by an involvement of the internal auditory meatus (n = 8), headaches by a traction of the dura (n = 4), serous otitis media by a compression of the eustachian tube (n = 2), and asymptomatic lesions with no involvement of the adjacent structures (n = 2). Hearing and facial functions were preserved in all the cases treated by a noninvasive procedure. No recurrence or complication was reported in the patients who underwent operations. None of the noninvasively treated patients with cholesterol granulomas showed significant enlargement on follow-up imaging. CONCLUSION: Clinical manifestations of cholesterol granulomas depend on their anatomic location and the involvement of the adjacent structures. Aggressive lesions in patients with residual hearing can be drained via an infralabyrinthine or an infracochlear approach with minimal morbidity. Follow-up must be preferred for patients with nonaggressive lesions. Although magnetic resonance imaging provides a specific diagnosis tool for cholesterol granulomas, computed tomography is essential for an accurate evaluation of the location of the cyst and choice of the surgical procedure.

Adolescent↗