Carotid and cerebral CT angiography using low volume of iodinated contrast material and low tube voltage.

PURPOSE: To evaluate image quality of carotid computed tomography angiography (CTA) using a low voltage (80kV) and low amount of iodinated contrast material. MATERIALS-METHODS: A total of 101 patients referred for carotid CTA were randomly assigned to receive a specific protocol. In group A patients received intravenous administration of contrast material at a dose of 1mL/kg and CTA examinations were performed at 100kV. In group B, patients received intravenous administration of contrast material at a dose of 0.5mL/kg and CTA examinations were performed at 80kV. The same nonionic iodinated contrast material containing 370mg of iodine per mL was used in both groups. Attenuation values were measured from the center of specific arterial segments using regions of interest. Attenuation values above 300HU were accepted as significant. Institutional review board approval was obtained. RESULTS: A total of 50 patients were included in group A (38 men, 12 women; mean age, 63.56 years±13.18 [SD]) and 51 patients in group B (33 men, 18 women; mean age, 59.60 years±16.63 [SD]). A total of 1615 arterial segments (1515 common carotid artery-middle cerebral artery and 101 aortic arches) were analyzed. Venous contamination was not observed in either group. The mean attenuation values of all arterial segments in both groups were greater than 300HU. Mean arterial attenuation value in group B (499.22HU±97.25 [SD]) was significantly greater than in group A (374.36HU±73.79 [SD]) (P<0.01). Hemodynamically significant stenosis (grade III stenosis or >70%) was detected in 2 segments in group A and in 3 segments in group B, while grade IV stenosis (occlusion) was detected in 2 segments in group B. Distal common carotid artery dissection was detected in 1 patient and aortic dissection was detected in 1 patient in group B. Total dose-length product (DLP) value was significantly greater in group A (225.74mGy·cm±21.80 [SD]) than in group B (116.60mGy·cm±21.22 [SD]) (P<0.01). The mean tube current was similar in group A (2013.11mAs±195.92 [SD]) and in group B (2096.64 mAs±309.03 [SD]) (P<0.05). CONCLUSION: Carotid and cerebral CTA examinations using 128-section CT can be successfully obtained using an imaging protocol that combines low voltage and 50% reduction in the volume of iodinated contrast material. This provides good image quality with low radiation dose.

The association between mean platelet volume and coronary collateral circulation.

BACKGROUND: Platelets are important in the pathogenesis of atherosclerotic complications. Higher mean platelet volume (MPV) levels are related to greater in vitro aggregation, and have been identified as an independent risk factor for myocardial infarction, and for death or recurrent vascular events. AIM: To determine the relationship between MPV and the coronary collateral circulation. METHODS: The sample consisted of 96 patients with coronary artery disease, and patients were separated into two groups according to their poorly developed or well-developed collateral circulation. Coronary collateral vessels were analyzed according to the Cohen and Rentrop grading system of 0-3. RESULTS: All analyses were conducted using SPSS 11.5 (SPSS for Windows 11.5, Chicago, IL, USA). Continuous variables were expressed as mean ± SD, and categorical variables were expressed as percentages. Comparison of categorical and continuous variables between the group with well-developed coronary collateral vessels and the group with poorly developed vessels was performed using the chi-squared test and independent samples t-test, respectively. Platelet count and MPV values were similar between the two groups. CONCLUSIONS: Our study found that MPV levels are not related to coronary collateral circulation.  

Implantable cardioverter defibrillator pocket infection caused by Klebsiella pneumonia.

Like any other foreign bodies, implanted cardiac devices can become infected. Staphylococcus aureus and coagulase-negative Staphilococci are the most common causes of infections of pacemaker and defibrillator systems. In this case an implantable cardioverter defibrillator pocket infection caused by an extremely rare microorganism, Klebsiella pneumonia, is presented.