Clinical Use of Ultrasound Superb Micro-Vascular Imaging Technique in Patients with Hemophilia Treated with Standard Radiosynovectomy. Initial Report

Introduction: Ultrasound (US) is an easily well available, non-invasive imaging technology that is used as a first-line diagnostic examination, in patients with hemophilia, who developed arthropathy due to joint bleeding. US is used both to select patients for radiosynovectomy (RS) and also for a follow-up study. It  is especially important  in vascular imaging, where clear and precise hemodynamic data is presented in a visual , which is more sensitive than the standard one. Clinically significant challenges exist in detecting small or microflow states without the use of contrast media, particular in pts with synovial overgrowth, which is characteristic in patients with hemophylic arthropathy.  In this initial study we report the clinical use of e Superb Micro-Vascular Imaging technique ( colour -cSMI and grey scale mode mSMI ) in patients after radiosynovectomy in a short term follow-up.

Materials and Methods. There were 8 pts with hemophia,  advanced arthropathy and joint bleeding due to synovial overgrowth Standard qualification into RS in each case. Overall 18 RS were done, including  10 ankle, 6 elbow and 2 knee joints. All pts had initial before RS and follow-up study 1-2 months  and  3-6 months  after RS. All had clinical and US standard examinations, performed by the same physician. In each case the same methods of US imaging were  used, including position. All examinations were performed using Aplio 400 with linear transducer (9-12MHz) (Toshiba MSC, J). All images include cine mode collected during examination were reviewed  in each case. The final analysis includes an initial study compared to a follow-up of least 2 examinations using a quality scale of intensity of synovial vascularisation, based on SMI and  standard evaluation including thickness of synovium, echogenity etc were evaluated.

Results: All RS were without complications. Initial US indicated high vascular flow in affected joints in all pts, in a semiquantitative scale (cSMI  3.1 and mSMI 4.1 ). In the first follow-up  cSMI was 2.5 and mSMI was 2.83, in second follow-up studies cSMI 2.56 and mSMI 2.56. There were no  other deferrers  of imaging analysis, including other US elements of synovial overgrowth reductiona, echogenic improvement etc. Clinical single pt with elbow arthropathy did not respond to RS, which was documented in both cSMI and mSMI, without any differences between initial and  follow-up tests. 5 had response a clinical response  and 2 had minimal clinical response.

Conclusion:  The new Superb Micro-Vascular Imaging technique seems to be useful in the imaging/clinical evaluation of early response in pts with hemophilic arthropathy who had radiosynovectomy. The new US approach with cSMI and  mSMI is both high sensitive in detecting of  microvascular blood reduction in initial stage of clinical follow-up. Further analysis with higher number of pts and longer follow-up suld be performed to assess real value of this technology