ABSTRACT
BACKGROUND: Four different techniques for aorto-iliac magnetic resonance angiography (MRA) were assessed for accuracy using a digital subtraction angiography (DSA) gold standard. Surgeons' confidence in their ability to generate treatment plans with MRA and DSA was assessed, in consultation with a radiologist. METHODS: Two different two-dimensional (2D) time-of-flight (TOF) sequences, a phase-contrast sequence, and a contrast-enhanced (CE) MRA sequence were used. Receiver operating characteristic (ROC) curves were plotted and areas (A(z)) calculated from radiologists' readings. Surgeons' confidence in their ability to utilize the images for treatment planning was assessed with a 5-point Likert scale. Thirty-six patients were evaluated. RESULTS: CE MRA had a sensitivity, specificity, and A(z) of.92,.93, and.96, respectively, for stenoses 50% or greater. CE MRA performed better than other sequences, but the improvement compared with gated 2D TOF was not statistically significant. Interobserver agreement for CE MRA and DSA yielded identical Kappa values. Surgeons were most confident in DSA, followed by CE MRA, which was significantly preferred to other techniques. CONCLUSIONS: CE MRA closely approximates DSA in terms of diagnostic accuracy. Surgeons considering treatment plans are confident in the CE MRA technique, relative to other MRA methods.
Subject(s)
Aortic Diseases/diagnosis , Arterial Occlusive Diseases/diagnosis , Iliac Artery/pathology , Magnetic Resonance Angiography , Adult , Aged , Angiography, Digital Subtraction , Aortic Diseases/surgery , Arterial Occlusive Diseases/surgery , Contrast Media , Female , General Surgery , Humans , Iliac Artery/surgery , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Interprofessional Relations , Male , Middle Aged , Observer Variation , Patient Care Planning , ROC Curve , Radiology , Sensitivity and Specificity , Single-Blind Method , Statistics as TopicABSTRACT
PURPOSE: The wait tradeoff (WTO) is a simple time-tradeoff method designed for temporary health states that uses a realistic and intuitive interface for the patient/subject. This method was tested by assessing patients' preferences for magnetic resonance angiography (MRA) versus x-ray angiography (XRA). MATERIALS AND METHODS: The WTO was tested by telephone interview in 38 patients with atherosclerotic peripheral vascular disease, all having previously undergone both MRA and XRA. At indifference point, patients were ambivalent about having MRA or XRA and immediate treatment, versus having a waiting period for test results and treatment after a hypothetical "ideal test" that entailed no pain or risk. RESULTS: The patients were willing to wait a mean of 42.1 days after the ideal test for results and treatment, as opposed to XRA. They were willing to wait only 16.1 days as opposed to MRA. This difference in waiting times was significant (p = 0.0001) and indicates a clear preference for MRA, in agreement with known literature. CONCLUSION: The WTO method assesses preferences for these radiologic tests in an intuitive fashion that does not invoke artificial or irrelevant health states. This approach may also prove useful for other testing situations or short-term treatments being evaluated for cost-effectiveness.
Subject(s)
Patient Satisfaction , Peripheral Vascular Diseases/diagnostic imaging , Peripheral Vascular Diseases/diagnosis , Quality-Adjusted Life Years , Waiting Lists , Adult , Aged , Aged, 80 and over , Angiography/economics , Cost-Benefit Analysis , Female , Humans , Magnetic Resonance Angiography/economics , Male , Middle Aged , Models, Econometric , Time FactorsABSTRACT
RATIONALE AND OBJECTIVES: The authors assessed health-related quality of life changes associated with peripheral x-ray angiography and magnetic resonance (MR) angiography. MATERIALS AND METHODS: Utility (the desirability or preference that individuals exhibit for a particular health state) was assessed in 30 patients with peripheral vascular disease referred for angiography by using a rating scale, additional categoric scaling questions to separate preference from experience, a willingness-to-pay technique, functional and cognitive status questions, and a time trade-off technique. All patients underwent both MR angiography and x-ray angiography. RESULTS: Patients reported significantly (P < .05) less anxiety after the test, less pain after the test, fewer new physical limitations, and less effect on performance of daily activities with MR angiography. Findings from the overall rating scale and categoric scaling questions also significantly (P < .05) favored MR angiography. Patients were willing to pay a mean of 2.12% of annual income to avoid MR angiography and a mean of 7.41% to avoid x-ray angiography. The median quality-adjusted life gain required by patients to undergo the procedures was 52.5-60 days for x-ray angiography and 10.5 days for MR angiography, without discounting. CONCLUSION: X-ray angiography has more profound short-term adverse effects on life than does MR angiography. Preference-based measures can be adapted to elicit patient values for short-term health states as seen in radiology.
