Microfocus computed tomography analysis of early changes in bone microstructure in rats with chronic renal failure.
OBJECTIVE
Little is known about the microstructural changes in bone tissue in the early phase of chronic renal failure (CRF). In this study, we analyzed the bone tissue in a rat model of early CRF using a high-resolution X-ray tomographic system, i.e. microfocus computed tomography (MXCT), which is capable of detecting microscopic structural changes in bone tissue.


METHODS
CRF rats were created by 7/8 nephrectomy by ligation of the renal artery branches, and were sacrificed 24 weeks after surgery. MXCT and bone mineral densitometry by single-energy X-ray absorptiometry (SXA) were performed using extracted bone samples. Images obtained by MXCT were further analyzed by node-strut morphometry.


RESULTS
Biochemical analysis confirmed that CRF was induced in 7/8-renal artery-ligated rats. MXCT demonstrated a significant decrease in trabecular bone in uremic rats, whereas SXA was unable to detect the difference. The node-strut method revealed decreased trabecular connectivity, with little change in the thickness of the trabecular bone in uremic rats.


CONCLUSIONS
MXCT was able to detect significant changes in trabecular bone at an early stage of renal failure. The observed structural changes differed from those found in long-term dialysis patients. MXCT is a practical and promising device used for the non-invasive evaluation of early bone changes in uremic patients.
Kazama
Junichiro J
JJ
Division of Clinical Intensive Care Medicine, Niigata University Medical Hospital, Niigata, Japan. jjkaz@med.niigata-u.ac.jp
Iwasaki
Yoshiko
Y
Yamato
Hideyuki
H
Murayama
Hisashi
H
Sato
Masami
M
Gejyo
Fumitake
F
Kurokawa
Masafumi
M
Fukagawa
Kiyoshi
K
D015502:Absorptiometry, Photon / Q000379:methods; D000818:Animals; D015519:Bone Density / Q000502:physiology; D001842:Bone and Bones / Q000000981:diagnostic imaging* / Q000473:pathology; D004195:Disease Models, Animal; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007676:Kidney Failure, Chronic / Q000097:blood / Q000473:pathology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D014057:Tomography, X-Ray Computed / Q000379:methods*