Specific activation of operculum 3 (OP3) brain region during provoked tinnitus-related phantom auditory perceptions in humans.

The phantom sound perception mechanism by which a sound perception occurs without any external sound source is still enigmatic. According to our previous fMRI study, a small region in the parietal operculum 3 was hyperactivated as a function of tinnitus periodicity in subjects with acoustic trauma tinnitus sequelae. This region was localized in the vicinity of neural correlates of middle-ear tympano-ossicular chain movements due to pressure variations. Disturbed proprioceptors are known to trigger illusory perceptions; therefore, we hypothesized that a disturbance of middle-ear proprioceptors may originate phantom sound perceptions. We designed an fMRI study that aimed to stimulate middle-ear proprioceptors by repetitive vibrations using various rates of click trains. In this study, we report that exposure to specific rates of stimuli for a few minutes at comfortable intensity level in healthy subjects distinctly triggered transient tinnitus-like aftereffects. The fMRI neural correlates of the aftereffects were unequivocally localized in the same parietal region as in acoustic trauma tinnitus sufferers. Our results strongly suggest that a middle-ear kinesthetic/proprioceptive illusion exists at the origin of acoustic trauma tinnitus via a somatosensory pathway encompassing the trigeminal system.

Otosclerosis and Fitness to Fly.

BACKGROUND: When an aircrew member is referred for otosclerosis, his flight fitness may be questionable. The objective of this retrospective study was to describe a case series of otosclerosis in an aircrew population and to discuss the decisions about their flight waivers. METHODS: There were 27 aircrew members who were referred to the ENT-Head and Neck Surgery Department of the National Pilot Expertise Center. Their medical files were retrospectively examined. RESULTS: Out of 16 patients who had surgery, 2 did not obtain a flight fitness waiver afterwards. Among the 14 who received waivers, 12 had no restrictions on their flight fitness. Among the nonoperated patients, 1 of 11 did not obtain a waiver. Seven patients were declared medically fit to fly without a waiver and three obtained a waiver. DISCUSSION: Fitness was based on auditory and balance statuses and the follow-up of these findings. A postoperative CT-scan and the operative report were used to determine the quality of stapes surgery. Professional speech audiometry in noise might be as interesting. The results made it possible to determine a patient's fitness to fly with a waiver, which is more or less associated with restrictions. In our series, only 3 aircrew members out of 27 did not obtain a flight fitness waiver. The few published studies on the resumption of flight for patients who underwent surgery and our experience in France with similar waivers in commercial and military aviation suggest that under certain conditions and after relevant vestibulocochlear assessment, stapes surgery may allow for a safe recovery of aviation activity.

Vestibular schwannoma and fitness to fly.

INTRODUCTION: When a pilot is referred for vestibular schwannoma (VS), his or her fitness to fly may be questioned. The objective of this retrospective study was to describe a series of VS cases in a pilot population and to discuss their fitness to fly options. METHODS: Between September 2002 and March 2010, the ENT/Head and Neck Surgery Department of the National Pilot Expertise Center conducted nearly 120,000 expert consultations for 40,000 pilots. We examined the files of 10 pilots who were referred to our 2 national experts for VS. RESULTS: At the time of the expert consultation, hypoacusis was present in nine cases (four with total deafness), tinnitus in one case, and vertigo in nine cases. In our series, only 2 of the 10 pilots experienced a negative impact on their fitness to fly. DISCUSSION: Decisions on fitness to fly were based on several factors: minimally disturbed audition, i.e., less than a 35-dB hearing loss with a good speech discrimination score; good balance, i.e., no reported difficulties; no spontaneous nystagmus recorded on videonystagmography (VNG); no postural deviation; and a normal head-shaking test. The delay and the VS's evolution between diagnosis and expert consultation are important because the selection of a treatment to control VS is critical in minimizing the possible associated complications. When a pilot is referred for VS, his or her fitness to fly is determined by the size of the tumor, balance, auditory status, and the follow-up results of these findings. The complications that may arise from VS treatments must also be considered.

Susceptibility to tinnitus revealed at 2 kHz range by bilateral lower DPOAEs in normal hearing subjects with noise exposure.

We investigated potential markers of susceptibility to tinnitus in a group of normal hearing young pilots aged 25-35 years and with 8 +/- 5 years of aircraft noise exposure. 316 pilots were interviewed about their tinnitus status and were tested for hearing thresholds (audiograms) and distortion products otoacoustic emissions (DPOAE-grams). There was no subject with permanent tinnitus. 23% reported having occasionally perceived tinnitus after flight missions and 77% reported never having experienced tinnitus after flight missions. General discomfort in the ears to noise was higher in the occasional tinnitus group (15 vs. 6%). The major finding was that difference of susceptibility to tinnitus in normal hearing subjects exposed to noise on a daily basis seemed to be clearly related to lower DPOAEs, bilaterally, in the 1500- to 2800-kHz range. However, no difference could be observed between groups on audiograms at the 2-kHz frequency range. This study provided evidence of outer hair cell dysfunctions in normal hearing subjects exposed to noise and susceptible to tinnitus. Hypersensitivity to noise and decreased DPOAEs in a non-noise-specific frequency range support the idea of another alteration mechanism than noise itself. This point was discussed in the light of recent publications.

[Sinonasal mucosal malignant melanoma]. / Mélanomes des muqueuses nasosinusiennes.

INTRODUCTION: Mucosal melanomas are rare tumors, and primary sinonasal malignant melanomas uncommon tumors that are frequently misclassified. Differential diagnosis should rule out other sinonasal malignancies, including carcinoma, lymphoma, sarcoma, and olfactory neuroblastoma. CASE: We report two new cases of sinonasal melanoma. One involved a 68-year-old man being followed for chronic sinusitis, despite antibiotics; he presented a tumor of the right nasal cavity. The second case was that of a 77-year-old woman, referred for painful gingival swelling shown to involve osteolytic growth in the left maxillary sinus. In both cases, pathologic examination of the biopsy samples concluded that these were sinonasal malignant melanomas. DISCUSSION: Histologically, the diagnosis is very difficult because of the polymorphic features of this tumor, and immunohistochemical studies are very important. The relative inaccessibility of the mucosa to self-examination often delays diagnosis and leads to late detection and poor prognosis.

Follicular dendritic cell sarcoma of the tonsil: a case report.

Follicular dendritic cell sarcomas of the tonsil are very rare tumors. Only 10 cases have been published in the English-language medical literature. We present an additional case that occurred in a 27-year-old woman. She presented with a tumor of the right tonsil. Histological sections of tonsillar biopsies and tonsillectomy suggested that this tumor was a nerve sheath tumor or a malignant melanoma. Histological examination and immunohistochemical study were reviewed. The final diagnosis was follicular dendritic cell sarcoma. She underwent a transoral resection of the right oropharynx with ipsilateral selective neck dissection and postoperative irradiation. We emphasize the difficulties in diagnosing this type of tumor. The use of monoclonal specific markers is required to avoid misdiagnosis. We discuss therapeutic methods for this rare tumor for which optimal treatment has not yet been defined.

Hearing in military pilots: one-time audiometry in pilots of fighters, transports, and helicopters.

INTRODUCTION: Pilots are exposed to potentially harmful levels of noise, the actual consequences of which are still poorly documented. We have determined the audiometric profiles of pilots as a function of age and type of aircraft (i.e., fighter, transport, helicopter) and have searched for risk factors of deafness other than noise in a pilot population. METHODS: We examined 521 French military pilots ages 20-40 yr during their annual medical check-ups. Pilots were interviewed using a standardized questionnaire and data from tonal audiograms of both ears were collected. Hearing levels were compared between groups of age and aircraft category. RESULTS: Abnormal hearing levels in pilots were found essentially at high frequencies with a marked notch on audiograms at 6 kHz. Left ears had a significantly poorer performance compared with right ears. At a given age, transport pilots had, on average, better hearing at 8 kHz than other pilots, despite a higher number of flying hours. In addition to the 6 kHz notch, helicopter pilots showed a significant hearing loss at 3 kHz. Such an enlargement of the impaired frequency range can disturb speech communication. Prevalence of otitis media in childhood was significantly higher in pilots with abnormal hearing. DISCUSSION: Pilots flying fighter and helicopter aircraft are at a higher risk of hearing loss compared with pilots flying transport aircraft. Improvements in ear protection seem particularly needed for the left ear. Hearing losses can potentially compromise speech communication in helicopter pilots.