Assessment of Intracranial Arterial Stenosis with Multidetector Row CT Angiography: A Postprocessing Techniques Comparison

BACKGROUND AND PURPOSE: It was demonstrated the some patients with stroke have intracranial stenosis of 50% or greater and the identification of intracranial arterial stenosis is extremely important in order to plan a correct therapeutical approach. The aim of this study was to assess the image quality and intertechnique agreement of various postprocessing methods in the detection of intracranial arterial stenosis. MATERIAL AND METHODS: Eighty-five patients who were studied by using a multidetector row CT scanner were retrospectively analyzed. A total of 2040 segments were examined in the 85 subjects. Intracranial vasculature was assessed by using MPR, CPR, MIP, and VR techniques. Two radiologists reviewed the CT images independently. Cohen weighted κ statistic was applied to calculate interobserver agreement and for image accuracy for each reconstruction method. Sensitivity, specificity, PPV, and NPV were also calculated by using the consensus read as the reference. RESULTS: Two hundred fifteen (10.5%) stenosed artery segments were identified by the observers in consensus. The best intermethod κ values between observers 1 and 2 were obtained by VR and MIP (κ values of 0.878 and 0.861, respectively), whereas MPR provided the lowest value (κ value of 0.282). VR showed a sensitivity for detecting stenosed segments of 88.8% and 91.6% for observers 1 and 2, respectively. The highest positive predictive value was also obtained by VR at 95% and 99% for observers 1 and 2, respectively. Image accuracy obtained by using VR was the highest among all reconstruction methods in both observers (185/255 and 177/255 for observers 1 and 2, respectively). CONCLUSIONS: The results of our study suggest that VR and MIP techniques provide the best interobserver and intertechnique concordance in the analysis of intravascular cranial stenosis

Carotid plaque enhancement and symptom correlations: an evaluation by using multidetector row CT angiography

BACKGROUND AND PURPOSE: The identification of plaque characteristics that determine its vulnerability is extremely important. The purpose of this work was to evaluate CPE after administration of contrast material and to assess whether there is a statistical association between CPE and cerebrovascular symptoms. MATERIALS AND METHODS: Ninety-seven consecutive patients (69 men, 28 women; mean age, 62 years; age range, 39-82 years), studied by using an MDCT scanner, were retrospectively analyzed. Examinations were performed before and after administration of contrast medium. Plaque enhancement was analyzed, and the obtained data were compared with the patient's symptoms. Patients were classified as symptomatic (TIA or stroke with a temporal window of 6 months) or asymptomatic according to neurologic assessment and the TOAST criteria. The ROC curve and Az were calculated, and multiple logistic regression analysis was performed. RESULTS: Thirty-nine patients were excluded because they had calcified plaques (40.2%). CPE was observed in 74% of the remaining 58 patients. A statistically significant difference was observed between symptomatic and asymptomatic patients for the presence of CPE (P = .0013; OR = 7.5). Moreover, we observed that CPE was higher in fatty plaques (P = .035) than in mixed ones and more frequent in the former (P = .0119). The ROC curve demonstrated that a threshold of 15 HU is associated with a specificity and sensitivity of 83.33% and 76.47%, respectively. Multiple logistic regression showed that CPE and symptoms are associated (P = .0315). CONCLUSIONS: The results of our study suggest that for noncalcified carotid plaques, the presence of CPE is associated with cerebrovascular symptoms. Fatty plaques are more likely to have CPE compared with mixed plaque

A study of inferior vena cava anomaly: Evaluation using multi-detector-row CT angiography

Venous malformations, especially absence of inferior vena cava (IVC), are unusual and occasional findings during complementary abdomen examinations or as a consequence of acute venous thrombosis of the vena cava. Absence of inferior vena cava, caused by aberrant development within the 6–8 weeks of gestation, is a rare congenital anomaly. However, it has been recently confirmed as a major risk factor for the development of deep venous thrombosis, especially in young patients. We report a case of a 34-year-old female patient with inferior vena cava agenesis and deep vein thrombosis