Morphometric analysis of renal vessels - Advantage of the multisector areaapproach to cross-sections

OBJECTIVE: To determine the most accurate morphometric approach to overcomi ng the obstacles of limited number, angle of section and irregular contours of vascular structures in analyzing vascular sections of renal biopsies. STUDY DESIGN: The luminal area of 451 cortical arterioles in 65 Masson-tric home-stained renal sections uns assessed with a computer-assisted imaging s ystem connected to a Leica DMR microscope (Mikroskopic und Systeme GmbH, We tzlar Germany). The luminal area measured by the imaging system was used as the gold standard, against which three mathematical sector approaches and one classical approach were evaluated. The accuracy of these approaches was evaluated by means of the relative deviation from the measured value ann o f the degree of overestimation or underestimation. Intraobserver and intero bserver variability were determined for the most accurate mathematical appr oach. RESULTS: As compared to measured luminal area, the sector elliptical approa ch yielded the lowest relative deviation (13.4 +/- 12.5%), without signific ant overestimation ol underestimation (-0.6 +/- 18.3%). The intraobserver a nd interobserver correlation coefficients for this method were 82.3% and 86 .5%, respectively. CONCLUSION: The sector elliptical approach is the most accurate mathematica l approach to vascular sections in renal biopsies.