['A new assessment system for bone histology, termed the turnover-mineralization-volume system, is advocated for patients with chronic kidney disease-related mineral and bone disorder. The system measures cancellous bone volume (BV/TV) as a third major evaluation axis; however, the physiologic significance of BV/TV remains unclear.', 'Conventional bone histomorphometry was performed in 75 iliac bone samples obtained from dialysis patients. In 47 of the 75 samples, the remaining samples were subjected to direct microfocus x-ray computed tomographic observation. Quantitative morphologic examinations, including micro-bone mineral densitometry, and marrow space star volume, Euler number, and node-strut analyses, were performed in the virtual three-dimensional space reconstructed from the microfocus x-ray computed tomographic images.', 'The levels of BV/TV were comparable in each of the conventional bone histomorphometric criteria. No significant correlations were found between BV/TV and other parameters. Two- and three-dimensional BV/TVs were significantly correlated with cancellous bone mass but not with cortical bone thickness or cortical bone mass. Two- and three-dimensional BV/TVs were significantly correlated with trabecular bone connectivity as determined by marrow space star volume, Euler number, and node-strut analyses.'] Is cancellous bone volume an indicator for trabecular bone connectivity in dialysis patients?