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Carotid artery wall thickness: comparison between sonography and multi-detector row CT angiography
No full textIntroduction: Prospective studies have shown that an increased thickness of the carotid wall is a significant predictor of coronary and cerebrovascular complications. Our purpose was to assess the agreement between multi-detector row computed tomography (CT) angiography (MDCTA) and colour Doppler ultrasound (CD-US) in measuring carotid artery wall thickness (CAWT) and the intima-media thickness (IMT). Methods: Altogether, 97 subjects (age range 64-84 years) were prospectively analysed using a four-detector row CT and a sonographic scanner. In total, 46 subjects had shown cerebral ischaemic symptoms. CAWT and IMT were measured in each patient using MDCTA and CD-US (by applying a digital calliper), respectively. Continuous data were described as the mean value ± standard deviation and were compared using the Mann-Whitney U test. A p value <0.05 was considered significant. Bland-Altman statistics was employed to measure the agreement between MDCTA and CD-US. Results: CAWT ranged from 0.5 to 1.53 mm, with a mean value of 0.9072 mm. IMT ranged from 0.46 to 1.5 mm, with a mean value of 0.8839 mm. By analysing the Bland-Altman plot, we observed an excellent agreement between CD-US and MDCTA with a bias between methods of 0.023±0.0424 mm. A limit of agreement from -0.06 to 0.106 was recorded. Correlation coefficient r was 0.9855 (95% confidence interval 0.9808-0.989). Mann-Whitney U test indicated a p value of 0.377. Conclusions: Obtained results indicated a significant agreement between MDCTA and CD-US in the measurement of CAWT and IM
Substance P-like immunoreactivity in human sympathetic ganglia.
No full textAbstract
Substance P-like immunoreactive nerve fibres and terminals are found in the human sympathetic paravertebral ganglia in connection with postganglionic neurones. Substance P may act as neurotransmitter or neuromodulator in the autonomic transmission in man
Study of endoleaks after endovascular repair by using MDCTA
No full textAbstract
PURPOSE:
Our purpose was to investigate the multi-detector-row CT angiography (MDCTA) application in endoleak detection.
METHODS:
Fifty-nine patients that underwent endovascular aneurysm repair (EVAR) of an infrarenal abdominal aortic aneurysm with endoluminal stent graft were retrospectively studied. MDCTA scans were obtained after administration of 110-130 mL of contrast material using a 4-6 mL/sec flow rate. We made unenhanced, arterial (15-20 sec) and delayed (100 sec) acquisitions. For each patient four MDCTA datasets (pre-EVAR, 1, 6, and 12 months follow-up) were obtained. Each examination was studied by two observers. Kappa value was calculated in order to evaluate inter-observer agreement.
RESULTS:
Twenty-one endoleaks were detected in eighteen patients. Fifteen and eighteen endoleaks were detected by using biphasic arterial CT and biphasic delayed CT respectively (sensitivity of 71.4% and 85.7% respectively). We observed a positive correlation between the presence of endoleak and the increasement in aneurysm size. Interobserver agreement was 88.1% and kappa value was 0.685.
CONCLUSIONS:
Biphasic CT for endoleak detection is significantly superior to arterial and delayed phases respectively. We observed a good interobserver agreement
Imaging of the endoleak after endovascular aneurysm repair procedure by using multidetector computer tomography angiography
No full textAbdominal aortic aneurysms (AAA) are an important cause of death in elderly men. Most used treatment options are endovascular aneurysm repair (EVAR) and open surgical repair. After the endovascular stent graft placement, however, several complications may occur and an important complication of EVAR is endoleak formation which occurs in approximately one-fourth of patients. Endoleak represents a blood flow outside the stent graft lumen but within the aneurysm sac. For these reasons, unlike the minimal imaging follow-up that is typically performed after surgical repair, patients undergoing EVAR require a life-long postoperative surveillance imaging. In the last years, with the advent of multidetector-row CT (MDCT) scanners and the use of specific angiographic protocols (multidetector CT angiography, MDCTA), CT imaging became the most commonly used examination for endoleak detection. Moreover, the volume data obtained can be further rendered to generate high quality two-dimensional (2D) and three-dimensional (3D) images, that allow a better distinction between Endoleak type II, III and IV. Purpose of this study was to review and describe MDCTA potentialities in the detection of endoleak after EVAR procedures
Accessory renal artery stenosis and hypertension: are these correlated? Evaluation using multidetector-row computed tomographic angiography.
No full textBACKGROUND:
Renal artery stenosis may produce hypertension, and this condition is referred to as renovascular hypertension (RVH).
PURPOSE:
To evaluate, by using multidetector-row spiral computed tomographic angiography (MDCTA), whether a relationship between accessory renal artery stenosis and hypertension may be hypothesized.
MATERIAL AND METHODS:
214 patients (142 males, 72 females; mean age 66 years) who had previously undergone an MDCTA to study the abdominal vasculature were retrospectively studied. Patients with renal artery stenosis (RAS) were excluded from this analysis. The patients were studied by means of a four-detector-row CT, and scans were obtained after intravenous bolus administration of 110-140 ml of a nonionic contrast material with a 3-6 ml/s flow rate. As a second step, by means of statistical analysis, hypertension data were compared with findings of accessory artery stenosis. Two radiologists first independently reviewed the MDCTA images and then, in case of disagreement, in consensus. Interobserver agreement was calculated for all measurements.
RESULTS:
The overall number of detected accessory renal arteries was 74 in 56 of the 214 patients. Accessory renal artery stenosis was detected in 21 of the 56 patients. There was a difference in the prevalence of hypertension between patients with (n = 21) and without (n = 35) accessory renal artery stenosis (P = 0.0187). Interobserver agreement was good (kappa value 0.733).
CONCLUSION:
Any statistical association between the presence of accessory renal artery stenosis and hypertension could not be disclosed. However, accessory renal artery stenosis, detected by MDCTA, is an important pathological sign that the radiologist has to assess in the light of its possible association with hypertension
Agreement between multidetector-row CT angiography and ultrasound echo-color Doppler in the evaluation of carotid artery stenosis
No full textPURPOSE:
Stroke is a leading cause of severe disability in the western world. A correct diagnostic procedure to stratify risk is necessary in order to rapidly plan the most efficient therapy. The purpose of this work was to evaluate the agreement between ultrasound echo-color Doppler (US-ECD) and multidetector-row CT angiography (MDCTA) in determining the degree of carotid stenosis.
METHODS AND MATERIALS:
From January 2004 to February 2007, 187 patients who had previously undergone both US-ECD and MDCTA were studied retrospectively. For each patient, stenosis degree was measured by applying the North American Symptomatic Carotid Endarterectomy Trial criteria. Data derived from MDCTA and US-ECD were then compared to calculate the inter-technique variability by using Cohen kappa statistics. For all plaque types (fatty, mixed and calcified), inter-technique variability was assessed. The Wilcoxon signed-rank test was used to highlight differences between the procedures, and scatterplots were also calculated. As a gold standard, reference surgical comparisons were performed in 50 patients.
RESULTS:
The percentage of observed agreements in the evaluation of stenosis degree was 72.19% with a kappa value of 0.659 (95% confidence interval: 0.604-0.715) and a weighted kappa of 0.789. After the evaluating stenosis degree in fatty, mixed and calcified plaques, the percentages of observed agreements were 79.31, 74.58 and 64.29%, respectively, with kappa values of 0.738, 0.691 and 0.565.
CONCLUSION:
A good agreement between US-ECD and MDCTA in the evaluation of stenosis degree was observed, together with a remarkable difference between the 2 techniques in the assessment both of calcified plaques and of plaques showing a predominant calcific component
Carotid Artery Wall Thickness Measured Using CT: Inter- and Intraobserver Agreement Analysis
No full textThe purpose of this work was to compare inter- and intraobserver agreement in the analysis of CAWT by using MDCTA. The CAWT in 35 patients was quantified by 4 observers. Bland-Altman statistics were used to measure the agreement between observers. The results of our study demonstrated that the CAWT measured by using MDCTA shows a good reproducibility between observers by considering inter- and intraobserver agreement
Carotid artery wall thickness (CAWT) and enhancement patterns of the vascular wall by using multi-detector-row CT angiography
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