Imaging-guided prostate biopsy: conventional and emerging techniques.

Transrectal ultrasonography (US)-guided biopsy is the standard approach for histopathologic diagnosis of prostate cancer. However, this technique has multiple limitations owing to the operator's inability in most cases to directly visualize and target prostate lesions. Magnetic resonance (MR) imaging of the prostate overcomes many of these limitations by directly depicting areas of abnormality and allowing targeted biopsies. Accuracy in the detection of prostate cancer is improved by the combined use of standard T2-weighted MR imaging and advanced MR imaging techniques such as diffusion-weighted imaging, dynamic contrast-enhanced imaging, and MR spectroscopy. Suspicious-appearing regions of the prostate seen on MR images can be targeted at real-time transrectal US-guided biopsy to improve the diagnostic yield. MR imaging also can be performed for real-time guidance of transrectal prostate biopsy. Studies among patients who underwent at least one transrectal US-guided biopsy with a negative result before undergoing an MR imaging-guided biopsy showed improved detection rates with MR imaging-guided biopsy in comparison with the detection rates achieved with a repeat transrectal US-guided biopsy; however, MR imaging-guided biopsy is a more time-consuming procedure. A technique known as fused MR imaging- and transrectal US-guided biopsy, which relies on the coregistration of previously acquired MR images with real-time transrectal US images acquired during the procedure, shows promise but is limited by deformation of the prostate; this limitation is the subject of ongoing investigation. Another technique that is currently under investigation, MR imaging-guided prostate biopsy with robotic assistance, may one day help improve the accuracy of biopsy needle placement.

Increased Incidence of Carotid Artery Wall Changes and Associated Variables in Hemodialysis Patients without Symptomatic Cardiovascular Disease

Cardiovascular disease (CVD) is still the major cause of the morbidity and mortality in hemodialysis (HD) patients. The characteristics of major arterial changes, atherosclerosis and related risk factors in HD patients remain unclear. We aimed to evaluate the atherosclerotic process in asymptomatic HD patients and healthy volunteers, and to determine the association between the risk factor (s) and the atherosclerotic process in these groups. 92 HD patients (female: 43, male: 49) and 62 age and sex matched healthy volunteers (female: 27, male: 35) were enrolled in this study. Diabetics, smokers, and patients with symptomatic CVD were excluded. The right and left carotid intima-media thicknesses (CIMTs) were measured and plaque structures were studied by B-mode ultrasound. The mean CIMT in patients and control group were 0.79 +/- 0.16 mm and 0.54 +/- 0.09 mm, respectively. Mean CIMT in HD patients was thicker (p < 0.001) and the presence ratio of plaque was higher in patients group (n=38, %61.2 vs n=9, %17.3) (p < 0.001). Calcified type of plaque was more frequent in HD patients than control group. Age (r=0.48, p < 0.001), left ventricular mass (r=0.42, p < 0.05), and homocysteine (r=0.46, p < 0.01), mean hematocrit (r=-0.36, p < 0.05), plasma CRP (r=0.50, p < 0.001), ESR (r=0.43, p < 0.01) and albumin (r= -0.34, p < 0.05) levels were correlated with the CIMT measurements and plaque presence, significantly. -CIMT as an atherosclerotic process indicator is thicker in asymptomatic HD patients than healthy subjects. We concluded that in addition to various classical risk factors, uremic environment may also contribute to acceleration of the atherosclerotic process.