Validation of a 40 MHz B-scan ultrasound biomicroscope for the evaluation of osteoarthritis lesions in an animal model.
OBJECTIVE
To evaluate high frequency (40 MHz) B-mode ultrasound for the detection of osteoarthritis (OA) lesions of varying severity in an animal model of OA.


METHODS
Ultrasound biomicroscopy (UBM) was performed on the femoral articular surface of adult rabbits with unilateral transection of the anterior cruciate ligament at 4, 8 and 12 weeks post-surgery and on control rabbits. The articular cartilage was examined and graded macroscopically and histologically for OA lesions. Histological examination was used as a reference to determine sensitivity and specificity of ultrasonographic and macroscopic examination regarding fibrillation and ulceration of articular cartilage.


RESULTS
Identification of slight surface irregularities was made possible with UBM. The sensitivity and specificity of UBM were 92.3% and 96.4%, respectively, to detect histological fibrillation and 90.9% and 97.6%, respectively, to identify histological ulceration. Macroscopic examination using India Ink had a sensitivity and specificity of 80% and 96.4%, respectively, for fibrillation and 90.9% and 90.5%, respectively, for ulceration when compared to histology. A high correlation (rsp=0.90) was found between ultrasonographic and histological scores.


CONCLUSIONS
UBM of articular cartilage reflects histological structure and can accurately detect early changes such as fibrillation. UBM has the potential to be a valuable tool for the in vivo identification of early lesions of OA and for monitoring the disease or efficacy of novel therapy if it can be packaged in a minimally invasive format suitable for intra-articular imaging.
Spriet
Mathieu P
MP
Département de Sciences Cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada.
Girard
Christiane A
CA
Foster
Stuart F
SF
Harasiewicz
Kasia
K
Holdsworth
David W
DW
Laverty
Sheila
S
D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery; D002358:Cartilage, Articular / Q000000981:diagnostic imaging* / Q000473:pathology; D004195:Disease Models, Animal; D005269:Femur; D008297:Male; D033401:Microscopy, Acoustic / Q000379:methods*; D010003:Osteoarthritis / Q000000981:diagnostic imaging* / Q000473:pathology; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index