Contribution of magnetic resonance imaging for the diagnosis of median nerve lesion after endoscopic carpal tunnel release.

Deterioration of pre-existing signs or appearance of a nerve deficit raise difficult problems during the complicated course following endoscopic carpal tunnel release. One possible explanation is transient aggravation of nerve compression by passage of the endoscopy material, but these signs may also be due to incomplete section of the flexor retinaculum or an iatrogenic nerve lesion. Each case raises the problem of surgical revision. The authors report three cases of open revision in which MRI allowed a very precise preoperative diagnosis of the lesions and all of the MR findings were confirmed during surgical revision. In the first case, MRI showed section of the most radial branches of the median nerve (collateral nerves of the thumb, index finger and radial collateral nerve of the middle finger). The proximal origin of the nerve of the 3rd web space, above the retinaculum, an anatomical variant, was also identified. Section of 2/3 of the nerve of the 3rd web space, proximal to the superficial palmar arch, was observed in the second case. Simple thickening of the nerve of the 3rd web space, without disruption after opening of the perineurium, was observed in the third case. MRI therefore appears to be an examination allowing early and precise definition of indications for surgical revision in this new iatrogenic disease.

MR assessment of red marrow distribution and composition in the proximal femur: correlation with clinical and laboratory parameters.

OBJECTIVE: To correlate the MR appearance of the proximal femur marrow with clinical and blood parameters. DESIGN AND PATIENTS: The proportion of the femoral neck surface area occupied by red marrow was determined on T1-weighted magnetic resonance (MR) images of the hip in a series of 120 subjects, aged from 15 to 75 years, with ten females and ten males per decade, and correlated with clinical data. This parameter and the bulk T1 values of femoral red marrow were determined in 30 other subjects 25-46 years of age and correlated with their blood parameters. RESULTS: In the series of 120 subjects, the proportion of red marrow surface area decreased with age (P < 10(-4)) and was higher in female than male subjects (P < 10(-4)). Within each decade, the proportion of red marrow surface area was higher in females than in males between 25 and 65 years but neither before 25 nor after 65 years. In the series of 30 subjects, the proportion of red marrow surface area and bulk T1 values of femoral red marrow were significantly negatively correlated with hemoglobin blood levels but not with blood cell counts. CONCLUSION: The MR appearance of proximal femur red marrow is influenced by age and sex. A relationship with hemoglobin blood level is demonstrated.

MR imaging of the acetabular labrum: variations in 200 asymptomatic hips.

OBJECTIVE: The purpose of this study was to describe the MR appearance of the acetabular labrum in asymptomatic subjects and correlate the MR appearance with age and sex. MATERIALS AND METHODS: We evaluated high-resolution T1-weighted spin-echo coronal MR images of one hip in each of 200 asymptomatic individuals (84 men, 116 women; mean age, 44 years old; range, 15-82 years old). The labral shapes (triangular, round, flat, or absent), the intralabral signal intensity changes, and the possible extension of the intralabral signal intensity changes to the labral surface were assessed on two sections for each subject and correlated with age and sex. RESULTS: Triangle was the dominant shape seen on MR imaging (66%). However, its frequency decreased significantly with age. Absence of labrum was the second most frequent pattern (14%) and increased significantly with age. Round and flat labra were found in 11% and 9% of subjects, respectively, with no significant age correlation. The frequency of homogeneous labra with low signal intensity decreased with age. Intralabral areas of high signal intensity communicating with the free surface increased with age. CONCLUSION: The large variability of the MR appearance of the labrum in asymptomatic hips must be considered when interpreting MR examinations of patients in whom labral lesions are suspected.

[Hypersensitivity pneumopathies: x-ray computed tomographic aspects]. / Les pneumopathies d'hypersensibilité: aspects tomodensitométriques.

Chest radiographs and computed tomographic scans obtained from nineteen patients with hypersensitivity pneumonitis were reviewed retrospectively. Thirteen of them had a subacute form. Six of them had a chronic form. In subacute forms, CT scans were normal in two patients. In the 11 other cases, CT findings were ground glass attenuation (n = 10), nodules (n = 7) and linear opacities (n = 5). Ground glass attenuation was diffuse or patchy. Two patterns are quite suggestive of hypersensitivity pneumonitis: the association of micronodules and ground glass attenuation and the presence of hyperlucent secondary lobules within the ground glass. After cessation of exposure, CT showed a return to normal or improvement. Ground glass opacities, nodules and also linear opacities disappeared. CT scans were always abnormal in chronic forms. CT findings were linear opacities (n = 6), ground glass attenuation (n = 4), micronodules (n = 2) and cysts (n = 3).

[Transverse fracture of the body of C2. Apropos of a case]. / Fracture séparation sagittale transcorporéale de C2. A propos d'un cas.

INTRODUCTION: A new fracture of the body of C2 is described. The mechanism is an axial compression producing a body sagittal fracture spreading to the posterior arch with a separation effect. CASE REPORT: A 29 years old female fell from the second floor. Examination showed a head injury and upper neck stiffness. Specific radiological signs was reported on the standard X-ray. The fracture involved the body and the lamina of C2 with a sagittal separation. No neurological abnormality was detected. CT scan provided additional information and allowed the survey of bone healing. Non operative treatment was undertaken by minerva jacket for four months carying complete recovery. DISCUSSION: The mechanism of this fracture seems to be similar to Jefferson's fracture. Review of the literature showed that fractures of the body of C2 are uncommon. Their different types are discussed.