THE PRECISE DETERMINATION OF VASCULAR LUMEN AND STENT DIAMETERS - CORRELATION AMONG CALIBRATED ANGIOGRAPHY, INTRAVASCULAR ULTRASOUND, AND PRESSURE-FIXED SPECIMENS

Purpose: Luminal diameters measured in vivo by calibrated-catheter ang iography and by intravascular ultrasound were correlated with those ob tained from pressure-fixed histologic cross-sections to determine the accuracy of both methods. Methods: Angiographic and endosonographic di ameter measurements were performed in the center of stents placed in t he iliac arteries of 10 miniature pigs and were compared with luminal and stent diameters in post-mortem, pressure-fixed, histologic cross-s ections from identical locations. Results: Compared with histologic di ameters, magnification-corrected angiographic measurements still magni fied vascular luminal diameters by 0.7 +/- 0.71 mm (r = 0.41, Pearson; p < 0.003, Wilcoxon, matched pairs), whereas intravascular ultrasound measurements proved to be almost identical to the histologic lumina ( r = 0.95, Pearson; p > 0.5, Wilcoxon, matched pairs), Similarly, stent diameters correlated well between endosonographic and histologic meas urements (r = 0.91; p = 0.002), and less well between angiographic and histologic diameters (r = 0.62; p = 0.002). Conclusion: Since calibra ted angiography still overestimates vascular lumina, endosonography is the preferred technique for accurate in vivo measurements.