The glomerulus, a specialized bundle of capillaries, is the blood filtering unit of the kidney. Each human kidney contains
about 1 million glomeruli. Structural damages in the glomerular micro-compartments give rise to several renal conditions;
most severe of which is proteinuria, where excessive blood proteins flow freely to the urine. The sole way to confirm
glomerular structural damage in renal pathology is by examining histopathological or immunofluorescence stained needle
biopsies under a light microscope. However, this method is extremely tedious and time consuming, and requires manual
scoring on the number and volume of structures. Computational quantification of equivalent features promises to greatly
ease this manual burden. The largest obstacle to computational quantification of renal tissue is the ability to recognize
complex glomerular textural boundaries automatically. Here we present a computational pipeline to accurately identify
glomerular boundaries with high precision and accuracy. The computational pipeline employs an integrated approach
composed of Gabor filtering, Gaussian blurring, statistical F-testing, and distance transform, and performs significantly
better than standard Gabor based textural segmentation method. Our integrated approach provides mean accuracy/precision
of 0.89/0.97 on n = 200Hematoxylin and Eosin (HE) glomerulus images, and mean 0.88/0.94 accuracy/precision on
n = 200 Periodic Acid Schiff (PAS) glomerulus images. Respective accuracy/precision of the Gabor filter bank based
method is 0.83/0.84 for HE and 0.78/0.8 for PAS. Our method will simplify computational partitioning of glomerular
micro-compartments hidden within dense textural boundaries. Automatic quantification of glomeruli will streamline
structural analysis in clinic, and can help realize real time diagnoses and interventions.
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