Faculty Bibliography

OBJECTIVE: Doppler sonography is not commonly used in evaluation of cystic lesions with internal echoes. Here we report the use of the mechanical properties of color Doppler sonography to further characterize 3 spermatoceles. METHODS: Three patients who came to University of California San Francisco Imaging Center with painless unilateral scrotal enlargement were evaluated with sonography and were found to have large spermatoceles. Color Doppler sonography was applied to these spermatoceles, and digital video clips were obtained as the color beam was instituted. RESULTS: When color Doppler sonography was applied to each spermatocele, the internal echoes moved away from the transducer, resulting in an appearance similar to falling snow. CONCLUSIONS: The "falling snow" sign can be used to enhance the diagnosis of a spermatocele as well as to evaluate a superficial cystic lesion with echogenic fluid and internal microdebris that is difficult to distinguish from a solid mass.

OBJECTIVE: A congenital diaphragmatic hernia (CDH) is the most common intrathoracic extracardiac congenital anomaly, and it is associated with high mortality and other fetal abnormalities. Early diagnosis is essential for delivery planning and possible intervention. However, the in utero diagnosis of CDHs by sonography can be challenging. We report the utility of paradoxical movement of the intra-abdominal contents in identifying CDHs. METHODS: Two fetal cases were identified: 1 referred with a suspected CDH and the other with a mediastinal shift and a suspected congenital cystic adenomatoid malformation (CCAM). Real-time sonography was performed in both fetuses with attention on movement of the intra-abdominal contents during fetal breathing, particularly during inspiration. RESULTS: Real-time sonography in both fetuses showed paradoxical movement of the abdominal contents during fetal inspiration. In the case with the presumptive diagnosis of a CCAM, the paradoxical motion was essential in changing the diagnosis from a CCAM to a CDH. CONCLUSIONS: Paradoxical movement of the abdominal contents can be used in addition to the traditional sonographic signs in diagnosing CDHs.

Accumulating clinical evidence indicates increased aortic stiffness, an independent risk factor for cardiovascular and all-cause mortality, in type 2 diabetic and glucose-intolerant individuals. The present study sought to determine whether increased mechanical stiffness, an altered extracellular matrix, and a profibrotic gene expression profile could be observed in the aorta of the insulin-resistant Zucker fa/fa rat. Mechanical testing of Zucker fa/fa aortas showed increased vascular stiffness in longitudinal and circumferential directions compared with Zucker lean controls. Unequal elevations in developed strain favoring the longitudinal direction resulted in a loss of anisotropy. Real-time quantitative PCR and immunohistochemistry revealed increased expression of fibronectin and collagen IV alpha 3 in the Zucker fa/fa aorta. In addition, expression of transforming growth factor-beta and several Smad proteins was increased in vessels from insulin-resistant animals. In rat vascular smooth muscle cells, 12-18 h of exposure to insulin (100 nmol/l) enhanced transforming growth factor-beta1 mRNA expression, implicating a role for hyperinsulinemia in vascular stiffness. Thus there is mechanical, structural, and molecular evidence of arteriosclerosis in the Zucker fa/fa rat at the glucose-intolerant, hyperinsulinemic stage.