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A patient’s therapeutic plan is guided by a combination of their medical history, vascular test results, and physical examination. Diagnostic tests play an essential role in the detection of vascular disease from both a venous and arterial standpoint. The sooner vascular disease can be identified in an individual, the sooner both physicians and patients can work toward integrating therapies that will prevent or mitigate ulcer formation. Knowledge regarding the proper indications and interpretations of the various vascular studies is critical to the successful management of each patient.

Assessing hemodynamics in vasculature is important for the development of cardiovascular diagnostic parameters and evaluation of medical devices. Benchtop experiments are a safe and comprehensive preclinical method for testing new diagnostic endpoints and devices within a controlled environment. Recent advances in three-dimensional (3D) printing have enhanced benchtop tests by allowing generation of patient-specific and pathophysiologic conditions. We used 3D printing, coupled with image processing and computer-aided design (CAD), to develop a patient-specific vascular test device from clinical data. The proximal pulmonary artery (PA) tree including the main, left, and right pulmonary arteries, with a stenosis within the left PA was selected as a representative anatomy for developing the vascular test device. Three test devices representing clinically relevant stenosis severities, 90%, 80%, and 70% area stenosis, were evaluated at different cardiac outputs (COs). A mock circulatory loop (MCL) generating pathophysiologic pulmonary pressure and flow was used to evaluate the hemodynamics within the devices. The dimensionless pressure drop–velocity ratio characteristic curves for the three stenosis severities were obtained. At a fixed CO, the dimensionless pressure drop increased nonlinearly with an increase in (a) the velocity ratio for a fixed stenosis severity and (b) the stenosis severity at a specific velocity ratio. The dimensionless pressure drop observed in vivo was similar (within 1%) to that measured in moderate area stenosis of 70% because both flows were viscous dominated. The hemodynamics of the 3D printed test device can be used for evaluating diagnostic endpoints and medical devices in a preclinical setting under realistic conditions.

The Diagnostic Vascular Laboratory plays a central role in vascular practice. In the ­evaluation of patients with vascular disease, the first step is a history and physical examination. The next step to investigate vascular disease is often a noninvasive vascular test performed in the Diagnostic Vascular Laboratory. Therefore, it is essential that testing be performed using the highest standards to ensure an accurate diagnosis. To achieve a high degree of accuracy and consistency, the vascular laboratory personnel, including technologists, supervisors, and interpreting physicians, have to be highly qualified. This chapter describes the necessary qualifications for physicians providing interpretation in accredited vascular laboratories.

Objective: The present study was designed to investigate local and systemic responses to cold provocation testing as a simple vascular test for workers chronically exposed to cold. Materials and Methods: The study included 22 male workers from cold storage facilities and a matched non-exposed control group of 20 subjects. All participants were non-hypertensives and free from diabetes and cardiovascular diseases. They were subjected to a questionnaire, resting blood pressure measurement, cold provocation testing and Doppler radial systolic blood pressure measurement before and after cold provocation. Results: Hypertensive response was observed more significantly among cold exposed workers than controls (p= 0.003). Blanching response to cold was not significantly different between exposed and control groups. Coupled response was significantly higher among cold exposed workers than controls (p= 0,006) and it was independently determined by duration of exposure (p= 0.001). Conclusion: It seems that coupled response to cold provocation testing is a simple outcome measure for screening chronically exposed workers to cold.

Morphological characterization of carotid plaques has been used for risk stratification and evaluation of response to therapy, evaluation of new risk factors, genetic research, and for quantifying effects of new anti-atherosclerotic therapies. We developed a 3D US system that allows detailed studies of carotid plaques in 3D. Our software includes 3D reconstruction, viewing, manual and semi-automated segmentation of carotid plaques, and surface morphology analysis to be used for quantitative tracking of plaque changes. We evaluated our plaque quantification software by examining plaque volume measurement accuracy, variability, and plaque surface morphology. We used vascular test phantoms to study segmentation accuracy, and used 48 3D US carotid plaques of patients ranging in size from 13.2 mm(3) to 544.0 mm(3) to study plaque volume measurement variability. We compared results from the semi-automated plaque measurements to the results obtained from manual measurements, which were used as the "gold" standard. We developed a surface plaque morphology quantification technique based on the segmented plaque surface curvature and used it to analyze plaques. Accuracy of plaque volume measurements for the simulated plaques ranged from 4.2% to 1.5% for volumes ranging from 68.5 mm(3) to 286 mm(3). The variability study showed that coefficients of variation in the measurement of plaque volume decreased with increasing plaque size for both inter- (90.8-3.9%) and intra-observer (70.2-3.1%) measurements over the plaque sizes measured. Surface morphology analysis showed that 1 mm ulceration could be quantified and monitored for changes over time. The automated plaque quantification approach showed a little higher intra-observer variability than the manual technique, and its performance was better for segmenting the wall than the lumen. Our results indicate that our approach is sensitive tool and can be used in studies of plaque progression and regression as it relates to atherosclerosis treatment effects and can be used effectively in longitudinal studies for direct measurement carotid plaque volume.

Objectives: Uterine Doppler is used in screening for placentaassociated diseases, such as pre-eclampsia and intrauterine growth restriction of the fetus (IUGR). The aim of this study was to examine the predictive value of second trimester uterine Doppler in pregnancies complicated by systemic lupus eritematosus (SLE). Methods: Observational study on 55 pregnancies in women with SLE treated at our Unit from 2000 to 2008. The Doppler examination was performed between 23+0 and 25+6 weeks of gestation. The mean uterine artery pulsatility index (UtA PI) was calculated. Results: The median (interquartile range, IQR) UtA PI was 1.00 (0.90–1.20). Three patients had a mean uterine artery PI above the 95th centile for gestational age. All these patients developed pre-eclampsia and IUGR. No cases of pre-eclampsia or IUGR were observed in patients with the mean uterine artery PI below the 95th centile for gestational age. The sensitivity was 100% (95% CI 0.44–1.00), specificity was 100% (95% CI 0.93–1.00). Conclusions: In our series, the mean uterine artery PI was an excellent predictor for pre-eclampsia and IUGR in women with SLE.