Bone diseases in rabbits with hyperparathyroidism: computed tomography, magnetic resonance imaging and histopathology.
BACKGROUND
Hyperparathyroidism (HPT) occurs at an early age and has a high disability rate. Unfortunately, confirmed diagnosis in most patients is done at a very late stage, when the patients have shown typical symptoms and signs, and when treatment does not produce any desirable effect. It has become urgent to find a method that would detect early bone diseases in HPT to obtain time for the ideal treatment. This study evaluated the accuracy of high field magnetic resonance imaging (MRI) combined with spiral computed tomography (SCT) scan in detecting early bone diseases in HPT, through imaging techniques and histopathological examinations on an animal model of HPT.


METHODS
Eighty adult rabbits were randomly divided into two groups with forty in each. The control group was fed normal diet (Ca:P = 1:0.7); the experimental group was fed high phosphate diet (Ca:P = 1:7) for 3, 4, 5, or 6-month intervals to establish the animal model of HPT. The staging and imaging findings of the early bone diseases in HPT were determined by high field MRI and SCT scan at the 3rd, 4th, 5th and 6th month. Each rabbit was sacrificed after high field MRI and SCT scan, and the parathyroid and bones were removed for pathological examination to evaluate the accuracy of imaging diagnosis.


RESULTS
Parathyroid histopathological studies revealed hyperplasia, osteoporosis and early cortical bone resorption. The bone diseases in HPT displayed different levels of low signal intensity on T(1)WI and low to intermediate signal intensity on T(2)WI in bone of stage 0, I, II or III, but showed correspondingly absent, probable, osteoporotic and subperiosteal cortical resorption on SCT scan.


CONCLUSIONS
High field MRI combined with SCT scan not only detects early bone diseases in HPT, but also indicates staging, and might be a reliable method of studying early bone diseases in HPT.
Bai
Rong-jie
RJ
Department of Radiology, Fourth Affiliated Hospital of Harbin Medical University, Harbin 150001, China.
Cong
De-gang
DG
Shen
Bao-zhong
BZ
Han
Ming-jun
MJ
Wu
Zhen-hua
ZH
D000818:Animals; D001847:Bone Diseases / Q000175:diagnosis* / Q000473:pathology; D002118:Calcium / Q000097:blood; D005260:Female; D006961:Hyperparathyroidism / Q000150:complications*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010024:Osteoporosis / Q000175:diagnosis; D010758:Phosphorus / Q000097:blood; D011817:Rabbits; D036542:Tomography, Spiral Computed / Q000379:methods*
D010758:Phosphorus; D002118:Calcium