Annual Evaluations of MRI Findings of Hemophilia Arthropathy in 7 Years
Authors: Nakadate Hisaya , Ishiguro Akira , Matsumoto Kimikazu , Miyazaki Osamu , Nosaka Shunsuke 
Published: October 2019

Abstract
Objective
Recently, hemophilia care has been advanced with regular factor VIII replacement (prophylaxis) to prevent or postpone joint damage. It have been needed an accurate monitoring system for the evaluation of hemophilic arthropathy. Conventional radiography has been used to objectively evaluate hemophilic arthropathy. However, it visualizes primarily bone lesions that appear late in the process of hemophilic arthropathy. Magnetic resonance imaging (MRI) had been considered to accurately evaluate the early changes of these joint damages in hemophilic arthropathy.
We present our experiences of 7 years annual MRI assessment of arthropathy of the Japanese children with hemophilia, who were treated with sencondary prophylaxis or on demand therapy in comparison with conventional radiographic assessment.
Methods
From 2007 to 2013, 10 children , 7 hemophilia A and 3 hemophilia B ,were enrolled in this study. One patient was treated with primary prophylaxis , 6 pts with secondary prophylaxis, 4 pts with on demand therapy. We made annual MRI and X ray examinations to of hemophilic arthropathy assessments of 37 joints (bilateral knees and ankles of every patient). We used a complete MRI protocol, including T1-weighted, T2*-weighted and short tau inversion recovery (STIR), GRE (gradient echo) T2*) sequences in all the joints. Assessmen of MRI was done with according to the compatible MRI scoring system (Haemophilia 2005, 11, 116 - 122), and X-ray radiographic assesment was according to the Pettersson system.
Results
The damage grade of MRI findings were severe damage grade ; 5 joints, moderate grade ; 4 joints, mild grade ; 21 joints, no damage ; 7 joints. The damage grade of two joint were reduced and that of one joint was increased in 7 years. The progressive joint damage was found in 11 years boy with severe hemophilia A and he had been treated with on demand therapy .
Of the 173 studied joints, 49 (29.5%) had normal MRI findings, and 124 (70.5%) showed a various ranges of abnormalities. 58 joints (35.3%) had progressive damages in 7 years. Synovial hyperplasia and/or hemosiderin deposition was the main MRI findings in the affected joints (105/116, 90.5%). Cysts and/or erosions were the second in order finding (66/116, 56.9%). Although synovial hyperplasia was present, hemosiderin was not observed in 17 of 105 (16.2 %) joints, which suffered a few hemarthroses within the last 2 years. On X-ray radiographic evaluations, 57 of the 173 studied joints (34.3%) had a zero Pettersson score (0); however, 50% of them (29/57) presented with MRI alterations. The remaining 108 joints had radiological scores ranging between 2 and 13 points, nonetheless, in 70% (72/108) of cases MRI revealed more profound alterations than those observed by X-ray findings.
Conclusion
We considered that MRI assessment of patients' joints could identify the early changes of hemophilic arthropathy. But, this study is consisting of small numbers of joints observation, further studies are needed to confirm these findings.

Disclosures
No relevant conflicts of interest to declare.