A distinct MR imaging phenotype in amyotrophic lateral sclerosis: correlation between T1 magnetization transfer contrast hyperintensity along the corticospinal tract and diffusion tensor imaging analysis.

BACKGROUND AND PURPOSE: In the search for a diagnostic marker in ALS, we focused our attention on the hyperintense signal intensity in T1 MTC MR images along the CST, detected in some patients and not found in other patients with ALS and in control subjects. The aim of this study was to investigate the relationship between the hyperintense signal intensity in T1 MTC images and white matter damage. To this purpose, we studied potential heterogeneities in DTI values within our patients by using TBSS without a priori anatomic information. MATERIALS AND METHODS: In 43 patients with ALS and 43 healthy control subjects, the presence or absence of T1 MTC hyperintense signal intensity was evaluated. With a DTI analysis with a TBSS approach, differences in FA distribution between the 2 groups (patients with T1 MTC hyperintense signal intensity and patients without it) compared with each other and with control subjects were investigated. RESULTS: We found regional differences in white matter FA between patients with T1 MTC hyperintense signal intensity (37.2%) and patients without it. Patients with T1 MTC abnormal signal intensity showed lower FA strictly limited to the motor network and the posterior aspect of the body of the CC without extramotor FA reductions, whereas patients without this sign showed FA reductions in several confluent regions within and outside the CST and in the whole CC. CONCLUSIONS: T1 MTC hyperintense signal intensity in the CST and posterior CC, when present, is specific for ALS and represents, among patients with ALS, a possible distinct phenotype of presentation of the disease with prominent UMN involvement.

[Pneumothorax in multiple trauma. Radiologic and CT study]. / Pneumotorace nei politraumi. Studio radiologico e TC.

This study was aimed at evaluating the necessity to perform chest Computerized Tomography (CT) in multiple traumatized patients to diagnose pleuropulmonary lesions and, particularly, pneumothorax: the correct identification of this condition, although minimal, is important especially in prevision of long anesthesias and/or positive end-expiratory pressure (PEEP) therapy. This assisted respiratory technique improves arterial oxygenation but causes a barotrauma which may cause some complications; particularly, a small undetected pneumothorax can suddenly increase so as to cause pulmonary collapse with sometimes dramatic symptoms. Chest X-ray films and CT scans, performed in rapid succession on patient's admission in Emergency Ward, were compared in 21 subjects. CT is indispensable in case of severe chest parietal lesions which can mask the radiological evidence of pulmonary or pleural conditions, as it occurred in 3 of our cases. Moreover, CT resulted more reliable than chest X-rays (18 versus 10 correct diagnoses) especially in the detection of small antero-inferior pneumothorax flaps, in which direct radiological signs cannot be identified, in default of radio-geometrical assumptions. Indirect radiological signs of pneumothorax must be recognized but critically considered in order to avoid over-staging.