[Sudden deafness: value of imaging. Results from a prospective study of 37 patients]. / Surdités brusques: intérêt de l'imagerie. A propos d'une étude prospective de 37 cas.

PURPOSE: Review the CT and MR imaging findings in patients with sudden deafness (SD). PATIENTS AND METHODS: Thirty-seven patients with SD were prospectively included. All patients underwent MR evaluation of the brain and temporal bones to exclude classical etiologies such as vestibular schwannoma. CT of the temporal bones was also performed to exclude lesions of the bony labyrinth. A total of 100 CT examinations of the temporal bone in control subjects were reviewed and measurements obtained to establish a reference standard to compare to findings in our patient population. RESULTS: Findings included: vestibular schwannoma in 2.7%, labyrinthine hemorrhage in 8.1%, bony labyrinthine anomaly in 59.5% according to our criteria, and significantly more frequent than in our control subjects, including dehiscence of the superior semicircular canal in 8.1%, lateral semicircunal canal anomaly in 27% and vestibular anomaly in 16.2%. CONCLUSION: Some of the classical etiologies of SD were detected in our patient population, along with a high prevalence of size or morphological anomalies of the bony labyrinth, diagnosed in most cases from systematic measurements from CT images. In time, MRI should also allow detection of these abnormalities and diagnosis of lesions currently not detectable on MRI.

[Cochlear otosclerosis and pseudo fourth turn of the cochlea]. / Otospongiose cochléaire et pseudo-quatrième tour de cochlée.

OBJECTIVE: To describe different sequences on magnetic resonance imaging (MRI) in otosclerosis with peri-cochlear involvement. METHOD: MRI T1 and T2 sequences with T1 gadolinium injection and computed tomography (CT) scans with millimetric slices on axial and coronal views were obtained. The diagnosis of bilateral otosclerosis was confirmed by surgical exploration. RESULTS: On the CT scan, there was a fourth turn of the cochlea which appeared on the MRI T1 sequence with an intermediate signal and on the T2 sequences with a high intensity signal. After gadolinium injection, there was signal enhancement, suggestive of active otospongiosis. On the CT scan, there was another lesion in front of the cochlea with endosteal involvement. This was no however visible on the MRI, even after gadolinium infusion, in accordance with inactive otospongiosis. DISCUSSION: We reviewed the literature concerning MRI and results in otosclerosis. CONCLUSION: MRI of the labyrinth with T1 sequences and gadolinium injection can be contributive to the diagnosis of otosclerosis to differentiate inactive from inactive otospongiosis. However, prospective studies must be conducted to confirm this hypothesis.

[Advantage of virtual endoscopy in the evaluation of the ossicular chain]. / Intérêt de l'endoscopie virtuelle dans l'exploration de la chaîne ossiculaire.

PURPOSE: Our study consists of a comparison of traditional computed tomography (CT) data sets with 2 views of virtual endoscopy in the preoperative evaluation of various diseases of the middle ear. MATERIALS AND METHODS: We studied 59 patients, all sent for conductive hearing loss with normal eardrum who underwent a complete CT examination: axial helical acquisition and coronal incremental acquisition: virtual endoscopy with selection of two reproducible views: an external one of the auditory canal and a lower one of the hypotympanum. Reading was performed by 2 independent radiologists. All patients were subsequently operated by the same surgeon. Results were compared with surgical reports. RESULT: Virtual endoscopy is valuable for the evaluation of ossicular and prosthesis dislocations, morphological anomalies of the malleus, incus, and stapes superstructure. Nevertheless, standard axial and coronal CT images remain necessary as confirmed by the poor results of virtual endoscopy in cases of attic obstruction, cholesteatomas and otospongiosis. CONCLUSION: Virtual endoscopy is a valuable technique of the evaluation of some ossicular chain pathologies but it cannot be used alone.

Preliminary study of the deposition of aerosol in the maxillary sinuses using a plastinated model.

In spite of the widespread use of aerosols in respiratory diseases, very few studies have been performed in the field of ear, nose, and throat (ENT) disorders. The conditions for penetration of aerosols inside the sinus cavities are thus still not understood fully. The aim of this study was to investigate the penetration of aerosols inside maxillary sinuses in vitro, using plastinated models. Three plastinated specimens of the nose and sinuses were made from three different corpses. These specimens were validated by CT scans and were used to study deposition of aerosol in the maxillary sinuses. We performed scintigraphic images of the models in above, face, and profile views using a technetium (99mTc)-labelled solution to show aerosol deposition. We also counted the radioactivity deposited on gauze compresses placed inside the maxillary sinuses. In addition, we constructed a measuring unit with miniature humidity sensors placed inside the sinuses. We recorded the changes in relative humidity observed during nebulization. Results from these studies showed that scintigraphic images of the specimen, whatever the incidence of the views, were not accurate enough to differentiate the aerosol deposition in the maxillary sinuses from that in the nasal cavity. Using indirect counting on gauze compresses made possible the quantification of local aerosol deposition, and we found that aerosols entered into the sinuses. This confirmed that aerosols could reach the middle meatus, which is the main area for sinusitis disorders. The increased activity compared to background varied from 17 to 127%. The humidity sensors recorded changes in relative humidity during the nebulization. These humidity changes fitted a nonlinear model represented by the equation: y = b0 (1 - e(-b1t)), where b0 is the plateau and b1 is the speed to reach the plateau. These techniques may be useful in the future for in vitro characterization of aerosol penetration into the maxillary sinuses.

[Imaging and pathology of the ear and temporal bone (except for the skull base)]. / Imagerie et pathologie de l'oreille et du rocher (base du crâne exceptée).

Imaging occupies and increasing place in the investigation of pathological processes of the ear and temporal bone. For some of them (malformations, inflammatory conditions and tumours) the authors detail their indications and results. They conclude that imaging has become increasingly necessary in these conditions, and indispensable not only for choosing the method of treatment but also for medico-legal reasons.

The relations between physical ability and bone mass in women aged over 65 years.

In this cross-sectional study of 55 women (mean age 73.54 +/- 5.87), the magnitude of the relation between different indices of physical ability and confounding factors to bone density were determined. Physical fitness was assessed by direct measurement of maximal oxygen consumption (VO2 max), isokinetic muscle strength, and quadriceps and psoas muscle surfaces and densities using computed tomography. Anthropometry, chronological and gynecological ages, and dietary calcium intake were also recorded. The bone mineral density (BMD) was evaluated at the axial level (lumbar spine and proximal femur) and at the peripheral level (radius and tibia, cancellous and cortical compartments). Parameters related to physical ability proved to be the best predictors of BMD in radial and tibial cancellous compartments, spine, femoral neck, and trochanter, accounting for 15-27.5% of the total variance. The VO2 max was a major determinant of the femoral mineral density and one of the predictors of radial and tibial cancellous compartments. Psoas parameters were strongly related to spine mineral density and also constituted a predictor of radius (cancellous) and tibia mineral densities. The arm muscle strength could predict, though weakly, the BMD of axial skeleton, whereas thigh muscle strength only predicted the BMD of inferior limbs. No correlation was observed between current dietary calcium intake and BMD. Age-postmenopause and fertile life remained predictive of BMD at mostly cancellous sites, whereas anthropometry exerted important effects on radial and tibial cortices. The study suggests distinct sets of relations between physical ability and the BMD variables. Subjects with greater and denser psoas muscles had greater spine BMD, and those with higher VO2 max had greater proximal femur BMD.