Tranacranial Color Doppler Sonographic Evaluation Of The Hemodynamics Of The Middle Cerebral Artery Stenting

ObjectiveTo compare the hemodynamic changes in patients with middle cerebral artery (MCA) stenosis before and after stenting by transcranial color Doppler sonography (TCCS) and to explore the value of TCCS in assessing MCA stentingMethodsThirty-seven MCA stenting candidates with MCA M1 segment stenosis were included in this study. Temporal window was adopted as the acoustic window. TCCS or Color Doppler Energy technique was initiated to display the MCA, the anterior cerebral artery, posterior cerebral artery and posterior communicating artery.. Then, Vascular Enhancement Technology (VET) used in 18 patients and three-dimensional (3D) TCCS was used in 2 patients to display the stent and MCA. The maximum systolic and minimum diastolic flow velocities (Vmax, Vmin), the time-averaged peak flow velocity (Vmean) and the resistance index (RI) were acquired by pulsed-wave Doppler (PWD). Hemodynamic changes of MCA before and after stenting were evaluatedResultsMosaic blood flow signals were found at MCA stenotic area shown by CDFI and PWD revealed the increased peak flow velocitie with high resistance in most of the segments. MCA lumen were clearly demonstrated in 28 patients using VET. The Hyperechoic stents were clearly demonstrated in 35 patients. The MCA maximal (Vmax), minimal (Vmin) and mean (Vmean) flow velocities were: Vmax =(282.46±57.7) cm/s, Vmin = (150.95±51.84)cm/s, Vmean = (220.76±57.42)cm/s; Vmax = (150.03±23.10)cm/s, Vmin= (80.65±8.04)cm/s, Vmean = (115.3±13.21)cm/s; Vmax =(109.59±10.36)cm/s, Vmin = (52.32±8.99)cm/s, Vmean = (75.95±9.93)cm/s before, immediately after and one week after the stenting, respectively.The flow velocities significantly decreased both immediately and one-week after the stenting compared to that before stenting (P<0.05). The flow velocities decreased further one week after the stenting compared to that immediately after the stenting (P<0.05). Twelve patients were followed up till six months, and the MCA flow velocities in these patients were within normal range and kept significantly lower than those before and immediately after the stenting, but did not show significant difference compared to that one week after stenting by statistics. ConclusionTranscranial color Doppler sonography could be an ideal and the first choice of method for evaluating the hemodynamic changes of MCA stenting.