Bertrand Duvoisin

Prospective comparison of MR enteroclysis with multidetector spiral-CT enteroclysis: interobserver agreement and sensitivity by means of "sign-by-sign" correlation

Abstract. Our objective was a prospective comparison of MR enteroclysis (MRE) with multidetector spiral-CT enteroclysis (MSCTE). Fifty patients with various suspected small bowel diseases were investigated by MSCTE and MRE. The MSCTE was performed using slices of 2.5xa0mm, immediately followed by MRE, obtaining T1- and T2-weighted sequences, including gadolinium-enhanced acquisition with fat saturation. Three radiologists independently evaluated MSCTE and MRE searching for 12 pathological signs. Interobserver agreement was calculated. Sensitivities and specificities resulted from comparison with pathological results (n=29) and patients clinical evolution (n=21). Most pathological signs, such as bowel wall thickening (BWT), bowel wall enhancement (BWE) and lymphadenopathy (ADP), showed better interobserver agreement on MSCTE than on MRE (BWT: 0.65 vs 0.48; BWE: 0.51 vs 0.37; ADP: 0.52 vs 0.15). Sensitivity of MSCTE was higher than that of MRE in detecting BWT (88.9 vs 60%), BWE (78.6 vs 55.5%) and ADP (63.8 vs 14.3%). Wilcoxon signed-rank test revealed significantly better sensitivity of MSCTE than that of MRE for each observer (p=0.028, p=0.046, p=0.028, respectively). Taking the given study design into account, MSCTE provides better sensitivity in detecting lesions of the small bowel than MRE, with higher interobserver agreement.

Traumatic chest lesions in patients with severe head trauma: a comparative study with computed tomography and conventional chest roentgenograms.

In patients with severe craniocerebral trauma, who need a continuous positive-pressure breathing, the detection of pulmonary and mediastinal traumatic lesions, especially pneumothorax, may alter the management. The aim of this study is to evaluate the efficiency and accuracy of conventional supine chest roentgenograms to detect the associated traumatic chest lesions in severe craniocerebral trauma and to compare their value as a diagnostic method for the identification of unsuspected lesions with a limited chest computed tomographic (CT) examination. Forty-seven consecutive patients with severe craniocerebral trauma underwent head CT and a prospective limited CT examination of the thorax in the same session. Nine patients (19.1%) presented a pneumothorax, bilateral in one case. Six pneumothoraces (60%) were identified both on conventional chest roentgenograms and CT, whereas in four cases (40%), the lesion was only detectable on CT. The CT study also showed 31 areas of pulmonary parenchymal contusions in 19 subjects (40%), whereas the conventional chest roentgenograms demonstrated 17 areas of contusions in 11 (23%) subjects. One thoracic aorta and one right diaphragm rupture were detected on CT study. On the conventional chest roentgenograms the mediastinal vascular injury was overlooked, whereas the right diaphragmatic rupture was highly suspected. The limited chest CT examination supplied additional information in 30% of patients. In 12.7% of patients, this information was clinically significant enough to alter the management. In patients with severe craniocerebral trauma evaluation of associated chest trauma by a supplementary limited chest CT, examination provides more and precise information about the size and severity of mediastinal and pulmonary lesions with a superior detectability of pneumothorax.

Magnetic resonance findings in 92 acoustic neuromas

A retrospective analysis of the MR findings in 92 cases of acoustic neuromas is presented. The method of examination included in all cases intravenous injection of Gadolinium (Gd-DTPA or DOTA) with realization of sections in the axial and coronal planes. In 21 cases native MR studies were performed in the axial plane, before Gadolinium injection, with T1WI (n = 21), and T2WI (n = 6) images. Tumors were strictly intracanalar in 19 cases (20.7%), only localized in the cerebellopontine angle (CPA) in 5 cases (5.4%), and in 68 cases (73.9%) the tumors had intra- and extracanalar components. In this last group of lesions, 63.2% completely filled the internal auditory canal (IAC), and 36.8% occupied the internal portion of the IAC. In most cases (85.3%) the mean diameter of the CPA component was less than or equal to 2.5 cm. Lesions were more frequently homogeneous (58.8%) after Gd i.v.-enhancement. Heterogeneity was noted mainly in large lesions (greater than 2.5 cm: 100%). In all cases but one, the tumors were round, or oval-shaped, well-delineated, and did not present significant contact with the petrous bone. In 80.9% of CPA lesions, the center of the tumor was posteriorly excentered in relation to the internal auditory canal, whereas it was centered in 16.2% of cases. Widening of the IAC was observed in 51.1% of cases. In 45.2% of tumors of the CPA, smoothing of the posterior edge of the porus was visible.

Mediastinal and hilar lymphadenopathy due to Pneumocystis carinii infection in AIDS patients: CT features.

Objective Extrapulmonary involvement by Pneumocystis carinii (PC) in acquired immunodeficiency syndrome (AIDS) patients is uncommon. Our purpose is to describe three AIDS patients with low cluster differentiation cell (CD4) counts, who were receiving aerosol pentamidine prophylaxis, and who had large noncalcified hilar and mediastinal lymphadenopathy. Materials and Methods Chest radiography, CT, and clinical and laboratory records of three AIDS patients who had radiographie evidence of mediastinal and hilar lymphadenopathy were retrospectively reviewed. Results Symptoms were quite similar in all patients: weight loss, fever, cough, and mild dyspnea. Mediastinal and hilar widening was noticed on chest radiography. Contrast-enhanced chest CT revealed multiple noncalcified lymphadenopathy with supracarinal predominance in all cases. Mediastinos-copy with mediastinal and hilar lymph nodes sampling was performed in all patients. Histologie examination of the biopsy specimens demonstrated a necrotic foamy tissue without any calcification, and silver stain coloration showed abundant PC organisms in each case. Conclusion In AIDS patients, PC infection should be considered as a possible cause of noncalcified hilar and mediastinal lymphadenopathy along with such possibilities as atypical infections and neoplasms, especially in severely immunocompromised hosts (low CD4) with aerosol pentamidine prophylaxis.

Subperiosteal ganglionic cyst of the iliac wing

A 50-year-old woman presented having suffered for 5 months from intense left hip pain. She denied any history of significant trauma, fever, or malignancy. Her medical history was unremarkable, except for alcoholism. Physical examination showed reduced mobility of the left hip during internal and external rotation, and loss of strength of the left iliopsoas muscle. Laboratory findings were normal. Plain radiographs showed osteoarthritis of the left hip, but no lesion in the left iliac wing or adjacent soft tissues. Radionuclide bone scan demonstrated localized mildly increased bone activity in the left iliac wing

Trauma of the Pulmonary Parenchyma

Pulmonary lesions are very common in blunt chest trauma patients [2, 4,18, 21]. Their incidence varies depending on whether they are defined clinically or radiologically: on computed tomographic (CT) examinations, pulmonary contusions are present in up to 70% of blunt chest trauma patients involved in motor vehicle accidents [2, 4, 18, 49] .

Mixed solid and cystic acoustic neuroma: MR features and differential diagnosis

We present a very rare case of combined cystic and solid acoustic neuroma investigated by magnetic resonance imaging (MRI). This case illustrates the value of MRI in the characterization of tumors in the posterior cranial fossa, particularly acoustic neuromas, and its diagnostic impact in unusual situations. The differential diagnosis of cystic and mixed lesions in the cerebellopontine angle is discussed.