Assessment of renal artery stenosis with CT angiography : Usefulness of multiplanar reformation, quantitative stenosis measurements, and densitometric analysis of renal parenchymal enhancement as adjuncts to MIP film reading

• Published in: Journal of computer assisted tomography Vol. 22; no. 4; pp. 533 - 540
• Main Authors: BERG, M. H, MANNINEN, H. I, VANNINEN, R. L, VAINIO, P. A, SOIMAKALLIO, S
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott 01-07-1998
• Subjects: Adult; Aged; Aged, 80 and over; Algorithms; Angiography - methods; Angiography - statistics & numerical data; Angiography, Digital Subtraction - instrumentation; Angiography, Digital Subtraction - methods; Biological and medical sciences; False Negative Reactions; False Positive Reactions; Female; Humans; Investigative techniques, diagnostic techniques (general aspects); Kidney - diagnostic imaging; Male; Medical sciences; Middle Aged; Observer Variation; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Renal Artery - diagnostic imaging; Renal Artery Obstruction - diagnostic imaging; ROC Curve; Sensitivity and Specificity; Statistics, Nonparametric; Tomography, X-Ray Computed - methods; Tomography, X-Ray Computed - statistics & numerical data; Urinary system; Performance evaluation; Human; Radiodiagnosis; Renal artery; High intensity; Quantization; Stenosis; Cardiovascular disease; Kidney; Arterial disease; Vascular disease; Image projection; Digital angiography; Pattern recovery; Diagnosis; Renal artery disease
• ISSN: 0363-8715; 1532-3145
• DOI: 10.1097/00004728-199807000-00007

Our goal was to evaluate CT angiography (CTA) in diagnosing renal artery stenosis (RAS).
Thirty-seven patients underwent digital subtraction angiography (DSA) and CTA. Visual interpretation and stenosis measurements were made from maximum intensity projection (MIP) and multiplanar reformation (MPR) laser film prints of 78 renal arteries.
Visual reading of MIP films showed good diagnostic performance by receiver operating characteristic curve analysis, with 100% sensitivity in the assessment of > or = 50% RAS but only 42-54% specificity (overall accuracy 60-75%). The false-positive rate decreased when MIP and MPR films were read together, but the excess of false negatives among the calcified lesions disabled this diagnostic algorithm. Combining visual interpretation of MIP films with quantitative measurements yielded the best diagnostic performance: 92% sensitivity, 80% specificity, and 84% overall accuracy. Renal cortical enhancement measurements (26 patients) had 81% overall accuracy.
The overall accuracy of CTA with MIP film reading can be enhanced by quantitative measurement of stenosis or reviewing MPRs.