Quantitative microcomputed tomography assessment of intratrabecular, intertrabecular, and cortical bone architecture in a rat model of severe renal osteodystrophy.
OBJECTIVE
To determine the effects of renal osteodystrophy (ROD) on bone microarchitecture in growing rats.


METHODS
A total of 24 rats underwent 5/6 nephrectomy (NX) and were fed a high-phosphorus diet to induce ROD; another 6 underwent sham NX. In vitro microcomputed tomography images (GEMS, London, Ontario, Canada) were obtained in the femoral metaphysis and midshaft.


RESULTS
Trabecular and cortical bone volume/total volume (BV/TV) were significantly lower in NX specimens because of pores within the trabeculae and along the endosteal surface. Topological analysis using component labeling in 3-dimensions verified that trabecular pores connected to the marrow space. After the trabecular pores were filled using a morphological filter, trabecular thickness was significantly increased in NX. In contrast, cortical thickness was significantly decreased in NX compared with controls; however, after filling the endocortical pores, thickness did not differ.


CONCLUSIONS
The ROD resulted in decreased cortical and trabecular BV/TV, increased porosity, and increased trabecular thickness. Advanced image processing algorithms demonstrated the effects of cortical and trabecular porosity on BV/TV and structure in ROD.
Hopper
Tim A J
TA
School of Physical and Chemical Sciences, Queensland University of Technology, Brisbane, Australia.
Wehrli
Felix W
FW
Saha
Punam K
PK
Andre
Jalal B
JB
Wright
Alexander C
AC
Sanchez
Cheryl P
CP
Leonard
Mary B
MB
D000818:Animals; D001837:Body Weights and Measures / Q000379:methods; D050071:Bone Density Conservation Agents / Q000008:administration & dosage; D002117:Calcitriol / Q000008:administration & dosage; D012080:Chronic Kidney Disease-Mineral and Bone Disorder / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000188:drug therapy; D004195:Disease Models, Animal; D005269:Femur / Q000000981:diagnostic imaging*; D013006:Growth Hormone / Q000008:administration & dosage; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*
D050071:Bone Density Conservation Agents; D013006:Growth Hormone; D002117:Calcitriol