Our aim was to evaluate the effect of arthroscopic lysis and lavage of the temporomandibular joint (TMJ) oil synovial microvascularisation by comparing preoperative and postoperative grades measured by power Doppler ultrasonography (US). We Studied 22 patients with hypomobility, clicking, and pain in the TMJ. Power Doppler US were obtained preoperatively to assess the presence of synovial microvascularisation, and arthroscopic lysis and lavage were done after conservative treatment had proved unsuccessful. The severity of synovitis was assessed arthroscopically. The postoperative power DopplerUS scans were obtained 2 months later. Other arthroscopic variables were roofing, adhesions, chondromalacia, clicking, and pain.