Change in T2* relaxation time of Hoffa fat pad correlates with histologic change in a rat anterior cruciate ligament transection model.
The Hoffa fat pad (infrapatellar fat pad) is a source of post-traumatic anterior knee pain, and Hoffa disease is a syndrome leading to chronic inflammation of the fat pad. Herein, change in T2* relaxation time of the fat pad was measured in a rodent anterior cruciate ligament transection (ACLX) model in order to (i) examine the causal relationship of anterior cruciate ligament (ACL) deficiency and Hoffa disease and (ii) demonstrate the feasibility of using T2* as an imaging biomarker to monitor disease progression. Three groups of male Sprague Dawley rats (n = 6 each group), received either (i) no intervention; (ii) sham surgery at the right knee; or (iii) right ACLX. T2* relaxation time was measured and histology was examined in the Hoffa fat pad after surgery. At 13 and 18 weeks after surgery, T2* values were significantly higher in the right fat pad than the left (p < 0.001) and significantly higher in the ACLX group than the control and sham groups (p < 0.001). Histology showed fibrosis and degeneration of adipocytes in the right knees of the ACLX group. We conclude that ACL deficiency and Hoffa disease are causally related and that MRI T2* value can serve as an imaging biomarker of Hoffa disease progression.
Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.|Department and Graduate Institute of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan.
Chao-Ying
CY
Wang
Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.|Department of Medical Imaging and Imaging Research Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan.
Ping-Huei
PH
Tsai
Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Taoyuan, Taiwan.|Institute of Biomedical Sciences, Academic Sinica, Taipei, Taiwan.
Tiing Yee
TY
Siow
Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.|Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
Herng-Sheng
HS
Lee
Department of Mathematics, Tamkang University, Taipei, Taiwan.
Yue-Cune
YC
Chang
Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
Yi-Chih
YC
Hsu
Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.|Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan.
Shih-Wei
SW
Chiang
Institute of Biomedical Sciences, Academic Sinica, Taipei, Taiwan.
Ming-Huang
MH
Lin
Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan.
Hsiao-Wen
HW
Chung
Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.|Department of Medical Research, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
Guo-Shu
GS
Huang
D017667:Adipocytes / Q000166:cytology; D000273:Adipose Tissue / Q000473:pathology*; D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D018450:Disease Progression; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
Hoffa disease; MRI; T2* relaxation time; anterior cruciate ligament; infrapatellar fat pad