R. Perrone

Characterization of Atypical Cystic Renal Masses With MDCT: Comparison of 5-mm Axial Images and Thin Multiplanar Reconstructed Images

OBJECTIVE The purpose of this study was to investigate whether cystic renal masses are better characterized on thin axial and multiplanar reconstructed MDCT images than on 5-mm images. MATERIALS AND METHODS The records of 70 complex cystic renal masses in 59 patients (45 men, 14 women; mean age, 68 +/- 13 years) who underwent 64-MDCT at two medical centers were studied. Twenty-three of the masses were confirmed on the basis of the histologic findings and 47 in 2-4 years of follow-up. Images were reviewed in two sessions by two radiologists with 12 and 2 years of experience. In the first session, 5-mm axial images were analyzed, and in the second, thin axial images and multiplanar reconstructions. To assess intraobserver variability, analysis was repeated after 1 month. Statistical analysis was performed with Wilcoxons signed rank test, receiver operating characteristic analysis, and weighted kappa statistics. RESULTS Radiologists 1 and 2 detected thicker cystic walls (p < 0.001, p < 0.005) and septa (p < 0.03, p < 0.05) and fewer septa (p < 0.005, p < 0.002) on 5-mm axial images and assigned significantly different Bosniak categories than they did in analysis of the volume data (p < 0.04, p < 0.05). Variability was reduced in thin axial and multiplanar views. No significant differences were found in characterization of lesions as benign or malignant in review of 5-mm axial images and volume data sets. The areas under the receiver operating characteristic curve were 0.89 for 5-mm images and 0.96 for volume data sets for radiologist 1 and 0.87 and 0.90 for radiologist 2. CONCLUSION Analysis of volume data sets is associated with less intraobserver and interobserver variability than review of 5-mm axial images. Wall thickness and the number and thickness of septa may differ, resulting in assignment of different Bosniak categories. Diagnostic performance in characterizing lesions as benign or malignant, however, is not statistically different for the thick and thin images.

Evaluation of liver parenchymal blood flow with contrast-enhanced US: preliminary results in healthy and cirrhotic patients.

RATIONALE AND OBJECTIVES To determine whether changes in hepatic parenchymal blood flow in cirrhotic patients can be evaluated with contrast-enhanced ultrasound (US) after Levovist administration. MATERIALS AND METHODS Ten normal volunteers, 16 Child A and 16 Child C cirrhotic patients were evaluated with contrast-enhanced US. Frames obtained at progressively increasing pulse intervals of 2, 4, 7, and 10 seconds in the same scan plane during infusion of Levovist (300 mg/mL, 150 mL/h) have been digitally recorded. Pulse intervals versus signal intensity (PI-SI) plots were fitted to a straight line whose slope is proportional to the speed of blood in the liver parenchyma. Enhancement differences in late phase have been evaluated measuring the SI after 7 minutes from the beginning of the infusion. RESULTS The slope of the PI-SI plot of the Child A cirrhotic patients was significantly lower than the slope of the normal controls (P < 0.05); conversely, no significant differences were found between the slope of the patients with Child C cirrhosis and that of the normal controls. In comparison with the normal subjects, the average SI at late phase decreased significantly both in patients with Child A (P < 0.05) and Child C (P < 0.001) cirrhosis. CONCLUSION Microbubble contrast agents could provide a noninvasive tool to detect and monitor hemodynamic changes that occur in the cirrhotic liver. Changes in the hepatospecific properties at late phase have also been demonstrated.

Case Report: US Detection of Tendinous Metastasis from Malignant Melanoma

The introduction of high frequency transducers has considerably improved the application of US in the study of musculo-tendinous diseases. We report a rare case of tendinous metastasis from malignant melanoma. The tumour (high karyokinetic index, Clark level IV) arose 4 years earlier in the dorsal region. The patient was admitted for pain in the left knee. A nodular hypoechoic lesion, 0.8 cm in diameter, poorly marginated, located in the subcutaneous tissue and involving the patellar tendon was identified with ultrasound. Histological examination confirmed the diagnosis.

MRI of normal achilles tendon

To investigate the normal internal structure of tendons 11 volunteers without clinical evidence of tendinopathy were examined using conventional spin-echo T1-, T2- and proton-density weighted sequences. The Achilles tendon was chosen because of its high frequency of injury in athletic activity, large size, superficial position and because it is oriented nearly parallel to the static magnetic field, therefore minimizing the “magic angle phenomenon”. The tendons exhibited areas of slightly increased signal in four T1-weighted and in all but one proton-density-weighted scans. No intratendinous signal was detected in T2-weighted images. The possible origin of these findings is discussed. We conclude that the knowledge of these normal signals may be useful to avoid incorrectly diagnosing as pathological.

Primary lymphoma of the mandible with diffuse widening of the mandibular canal: report of a case.

A case of primary non-Hodgkins lymphoma (NHL) of the mandible with unusual radiographic presentation is reported. The panoramic radiography revealed diffuse widening of the right mandibular canal with ill-defined margins and absence of edge sclerosis. Computed tomography showed infiltration of the superior portion of the canal with involvement of the vestibular cortex of the bone and of the alveolar ridge.