Measurement of Cortical Bone Density in the Radius by Peripheral Quantitative Computed Tomography in Hemodialysis Patients

Akira Fujimori, MD, Department of Artificial Kidney, Konan Hospital, 1-5-16 Kamokogahara, Higashinada-ku, Kobe 658 (Japan) Dear Sir, In the uremic patients who develop secondary hyperparathyroidism, bone loss in the cortex would be more remarkable than in the trabecular bone, which may increase in some patients [1]. Since bone mineral density (BMD) of the lumbar spine determined by dual-energy X-ray absorptiometry does not help us evaluate the severity of the renal osteodystrophy, we used peripheral quantitative computed tomography (pQCT), which can separately determine cortical BMD and trabecular BMD of the radius, to examine the clinical importance of the measurement of the cortical BMD in hemodialysis patients. Measurement of BMD was performed as reported before [2], The device used was XCT-960 (Stratec-Norland, Germany and USA). Trabecular BMD was measured at the ultradistal site of the radius (at 4% of the length of the bone from the distal end). A more proximal site at 15% with abundant cortical bone was selected to measure cortical BMD. After a transsectional slice of the radius with 2.5 mm thickness had been obtained, 55% of the total bone area was removed from the periosteal surface, to peel