血管内超声多普勒技术对Budd-Chiari综合征介入治疗前后肾静脉及侧支循环血流速度变化的研究

目的研究介入治疗(PTA)对Budd-Chiari综合征(BCS)侧支循环及肾脏血液回流的影响.方法使用血管内多普勒导丝对BCS患者15例肾静脉和12例侧支循环PTA前后血流速度的变化进行测定及比较.结果PTA前较PTA后血流速度显著增加,平均峰值流速(APV)3.88±5.69cm/s vs10.54±5.26cm/s,P<0.001,最大峰值流速(MPV)4.82±9.04cm/s vs15.28±8.07cm/s,P<0.001(肾静脉);APV-1.68±4.25cm/s vs3.70±3.74cm/s,P<0.001,MPV-1.50±6.08cm/s vs4.10±4.46cm/s,P<0.001(侧支).部分逆生理方向血流变为生理方向,波形由平直状态变为二相或三相型.结论PTA术对BCS侧支循环及肾静脉血流动力学影响显著,PTA有利于正常血流的恢复.     

限流支架植入治疗TIPS引起的难治性肝性脑病

目的　评价限流支架装置在缩小 TIPS分流道直径对治疗由门腔分流引起的肝性脑病的有效性。　方法　 9例TIPS术后并发严重肝性脑病患者经颈静脉沿原肝内支架同轴植入可限制血流量的支架装置。　结果　限流支架植入未出现术中并发症 ,平均门静脉压力由术前 12± 4 .2 cm H2 O升至 2 0± 2 .6 cm H2 O,彩色多普勒超声显示分流道内血流减少 4 7.3%±15 .1% ,肝性脑病得到实质性改善和控制。血氨浓度及胆红素明显降低。　结论　用限流支架治疗门腔分流因起的肝性脑病是安全有效的     

MRI对急性Stanford B型主动脉夹层的形态及血液动力学的定量研究

目的 利用相位对比电影MRI(PC cine MRI)方法分析急性stanford B型主动脉夹层(AD)真腔和假腔内的血流特点及其与真腔塌陷程度的关系.方法 对11例急性Stanford B型AD患者进行真实稳态快速梯度回波(true FISP)、三维对比增强MR血管成像(3D CE MRA)、PC cine MRI检查,获得急性Stanford B型AD真腔和假腔内血流特点的定性、定量指标及真假腔的面积,真假腔血流速度、血流量及面积比较采用配对t检验,真腔塌陷程度与血流指标的相关性采用Pearson相关性分析.结果 胸主动脉(破口以远2 cm处)假腔平均面积为(8.10±2.93)cm2,真腔平均面积为(2.59±0.93)cm2,二者差异有统计学意义(t=-2.34,P＜0.05).假腔内平均血流速度[(2.81±0.73)cm/s]明显低于真腔[(15.52±2.84)cm/s],二者差异有统计学意义(t=-4.05,P＜0.01).真腔内平均血流量(36.32±5.37)ml,假腔内平均血流量(37.62±24.58)ml,差异无统计学意义(t=0.05,P＞0.05).腹主动脉肝门水平,真腔内平均血流速度[(10.46±5.57)cm/s]高于假腔内血流速度[(4.04±2.96)cm/s](t=-1.58,P＜0.05),该水平6例在收缩中晚期真假腔内血流方向相反,真腔内血流逆向,即真腔内为双向血流.真腔塌陷程度与假腔内血流速度和血流量密切相关(r分别为0.931和0.926,P值均＜0.01).结论 PC cine MRI能够定量测定AD真假腔的血流速度、血流模式,结合3D CE MRA可评价真腔塌陷程度,对AD的诊断、制定治疗方案和选择治疗时机具有重要的临床应用价值.     

腔-肺分流术对单心室长轴运动的影响

目的探索腔-肺分流手术对单心室长轴运动的影响。方法应用组织多普勒成像技术测定23例功能性单心室患儿腔-肺分流术前、术后房室瓣环运动速度等指标。结果单心室术后两侧壁房室瓣环的收缩期最大峰值速度(Sm)、舒张早期最大峰值速度(Em)、舒张晚期最大峰值速度(Am)均较术前显著降低(均为P<0.01),右侧壁Sm(7.8±2.0)cm/svs(5.6±1.4)cm/s,Em(11.1±4.6)cm/svs(8.3±2.7)cm/s,Am(10.6±3.5)cm/svs(8.0±3.0)cm/s;左侧壁Sm(7.1±2.3)cm/svs(5.8±1.3)cm/s,Em(10.9±3.9)cm/svs(9.5±3.4)cm/s,Am(10.5±4.0)cm/svs(8.4±2.7)cm/s。两侧的Em/Am比值均差异无显著性意义(P>0.05),手术前后平均Q-Sm间期也差异无显著性意义(105±15)msvs(104±16)ms,P>0.05。结论单心室腔-肺分流术后两侧壁房室瓣环运动速度Sm、Em、Am均较术前显著降低,而Em/Am比值、Q-Sm间期也无显著变化。     

非等势椎动脉MR血流定量测量

目的 探讨非等势椎动脉两侧血管血流量测量的意义.方法 对52例非等势椎动脉和30例等势椎动脉正常志愿者双侧椎动脉内血流进行MR相位对比电影法扫描,并通过流速分析软件测定流量.结果 等势椎动脉组右侧、左侧平均 血流量为(1.45±0.42) ml/s、(1.47±0.52) ml/s,平均峰值血流量为(2.18±0.69) ml/s、(2.24±0.74) ml/s.非等势椎动脉组优势侧、劣势侧平均血流量为(1.69±0.39) ml/s、(1.09±0.36) ml/s,平均峰值血流量为(2.92±0.85) ml/s、(1.81±0.77) ml/s.结论 非等势椎动脉血流量的测量对病变定位、定性具有重要的意义.     

改良式经颈静脉肝内门腔静脉分流术治疗肝静脉闭塞型Buddi-Chiari 综合征

目的阐述改良式经颈静脉肝内门腔静脉分流术(TIPS)的技术步骤和评价其对肝静脉闭塞型Buddi-Chiari综合征的治疗效果.方法 11例被诊断为Buddi-Chiari综合征的患者,经影像学证实为肝静脉广泛狭窄和闭塞后,接受改良式TIPS技术治疗,TIPS改良技术的关键在于假想肝静脉通道的设计与建立;术后对其门脉系统压力变化、分流道血流改变及内支架开通状况进行了24个月的随访.结果 11例患者全部成功地建立肝内门静脉-下腔静脉分流通道,临床症状得到改善;门静脉主干压力由分流前的平均(4.62±0.52) kPa (1 kPa=10.2 cm H2O)下降至分流术后的(2.16±0.21) kPa;术后24个月随访,分流道血液最大流率(Vmax)为(56.2±3.50) cm/s,内支架通畅7(7/11)例.结论改良式TIPS技术具有高技术成功率,为肝静脉闭塞型Buddi-Chiari综合征患者提供了新的治疗手段.     

直接性门腔分流与TIPS术的比较研究

目的:探讨在肝内门静脉与肝后段下腔静脉(RHSIVC)之间建立直接性门腔分流(DIPS)的可行性及安全性;比较DIPS术与TIPS术后的并发症、临床疗效及分流道通畅情况。材料和方法:随机将需行介入治疗的肝硬化门脉高压患者分入DIPS(D组)及TIPS(T组)。分别对两组患者实施直接性门腔分流(D组)及传统TIPS术(T组),对两组患者术前、术后各实验室检查值及门腔压力差的改变、分流道参数、术后30d的临床疗效及随访期内出现的并发症进行比较,并用彩超对两组患者分流道的通畅情况进行随访。结果:共30例(男/女27/3)门脉高压患者(其中3例合并肝癌)入选本组研究,平均年龄(54.83±13.33)岁(31~76岁)。分组后,D组14例,T组16例。所有介入性门腔分流术均成功。D组、T组患者分流道的平均初次通畅时间分别为(188±19.8)d及(171.3±15.8)d;两组差异无显著性(P=0.648)。结论:直接性门腔分流安全、可行;DIPS术后的并发症、近期临床疗效及分流道的通畅性与TIPS术后接近,有望成为治疗门脉高压及其并发症的新措施。     

改良经颈静脉肝内门体分流术双支架植入治疗肝硬化门静脉高压临床效果

目的 探讨采用改良经颈静脉肝内门体分流术(TIPS)和双支架植入治疗肝硬化门静脉高压的安全性和有效性。方法 回顾性分析2016年3月至2021年5月在解放军第九六〇医院接受治疗的92例肝硬化门静脉高压患者临床资料。对常规TIPS穿刺技术进行改良,采用覆膜支架和裸支架建立分流道,测量TIPS术前后门静脉主干压力。术后3、6、12、24、36个月进行规律随访,复查超声或CT,了解支架通畅情况。结果 92例患者完成TIPS术(常规TIPS 22例,改良TIPS 70例),技术成功率100%。术后血管造影显示支架内血流通畅,无手术相关严重并发症发生。门静脉主干压力由术前(44.1±6.8)cmH₂O降低为术后(23.0±3.4)cmH₂O,差异有统计学意义(P<0.01)。所有患者随访(21.4±7.9)个月(3～43个月),85例支架内血流通畅,4例分别于术后10、13、24、33个月出现分流道闭塞,再次植入1枚支架后血流恢复通畅,3例分别于术后4、18、30个月死于多脏器衰竭或消化道出血。术后1年、2年、3年累计支架通畅率分别为98.9%、...     

血管内多普勒超声对Budd—Chiari综合征介入治疗前后血流动力学变化的评价

目的 :检测Budd Chiari综合征 (BCS)患者血流动力学的变化及对BCS患者PTA术后即刻的效果进行评价。材料和方法 :使用血管内多普勒导丝对 2 7例BCS患者下腔静脉 /肝静脉 (IVC/HV)介入治疗 (PTA)前后血流速度、血流量和压力的变化进行测定及比较。结果 :IVC和HV病变远心端PTA后较PTA前的平均峰值流速、最大峰值流速及血流量显著增加 ,而压力显著下降。结论 :PTA有利于BCS患者IVC/HV血流动力学的恢复 ;血流动力学指标可作为BCS在PTA后IVC/HV再通的依据之一。血流速度的变化可以作为判定PTA治疗终点的可靠指标之一。     

肺动脉流速的MRI测量与多普勒超声比较研究

目的探讨相位对比法MR I(PC-MR I)测量肺动脉血流的准确性以及临床应用价值。方法①选取正常健康志愿者42例,随机分为2组,采用PC-MR I和多普勒超声测量了主肺动脉的内径、最大流速和平均流速。②采用公式分别计算出主肺动脉1个心动周期的血流量。结果①PC-MR I和多普勒超声测量主肺动脉的内径分别为(24.4±3.41)mm和(21.5±2.55)mm。②PC-MR I测量主肺动脉的最大流速和平均流速分别为(79.9±24.0)cm/s和(50.3±7.71)cm/s。③多普勒超声测量主肺动脉的最大流速和平均流速分别为(88.8±8.33)cm/s和(53.7±5.04)cm/s。④PC-MR I测量主肺动脉的血流量为(73.5±6.60)m l,多普勒超声测量主肺动脉的血流量为(69.0±10.6)m l。应用统计学方法成组样本均数t-检验分析2种测量结果,选择检验水平为α为0.05。结论PC-MR I可以准确测量肺动脉的血流速度和血流量,对评价肺动脉血流动力学的改变具有一定价值。     

Acute Increase in Hepatic Arterial Flow During TIPS Identified by Intravascular Flow Measurements

The purpose of this study was to investigate alterations of hepatic arterial flow during transjugular intrahepatic portosystemic stent shunt (TIPS) applying intravascular Doppler sonography. This prospective monocenter study included 25 patients with liver cirrhosis (alcohol induced [n = 19], chronic hepatitis associated [n = 3], primary biliary cirrhosis associated [n = 1], and cryptogenic [n = 2]) successfully treated with TIPS. All patients underwent intravascular hepatic arterial flow measurements during TIPS using an endoluminal flow sensor. The average arterial peak velocity (APV) and the maximum arterial peak velocity (MPV) were registered. Twenty-two patients (88%) showed increased APV, one patient (4%) showed unaffected APV, and two patients (8%) showed decreased APV after TIPS. The average portosystemic pressure gradient decreased significantly, from 22.0 ± 5.1 mmHg before TIPS to 11.0 ± 4.1 mmHg after TIPS (−50.0%; p < 0.0001). The average APV increased significantly, from 41.9 ± 17.8 cm/s before TIPS to 60.7 ± 19.0 cm/s after TIPS (+44.9%; p < 0.0001). The average MPV increased significantly, from 90.8 ± 31.7 cm/s before TIPS to 112.6 ± 34.9 cm/s after TIPS (+24.0%; p = 0.0002). These changes in perfusion set in within seconds after TIPS tract formation in all the patients with increased APV. We conclude that TIPS-induced portosystemic decompression leads to a significant increase in hepatic arterial flow. The changes occurred within seconds, suggesting a reflex-like mechanism.     

Early sonographic evaluation of the transjugular intrahepatic portosystemic shunt (TIPS)

The purpose of this study was to evaluate duplex and color Doppler findings in patients before and within 24 h after transjugular intrahepatic porto-systemic shunts (TIPS). Conventional duplex and color Doppler were used in the assessment of 19 patients who underwent TIPS as part of a prospective protocol. Patients were examined within 24 h before and after the procedure. Before TIPS, patency, flow direction, and peak flow velocity in the main portal vein and hepatic artery were studied, as well as patency and flow direction in hepatic veins, splenic vein, and inferior vena cava (IVC). Immediately after the procedure, sonographic identification of stent position, shunt patency, and flow dynamics were evaluated and patency and flow direction of hepatic veins, splenic vein, and IVC were determined. The portogram performed at the end of the procedure was compared with the 24-h sonographic studies after TIPS to determined sonographic/angiographic correlation. No intraparenchymal abnormalities or perihepatic fluid collections were detected after the procedure. The metallic stent was clearly seen in all patients. Mean peak shunt flow velocities were 139±50 cm/sec within 24 h after TIPS. Absence of flow through the shunt was correctly identified in one case and confirmed angiographically. Mean peak flow velocity in the portal vein before TIPS was 22±13.6 cm/sec and increased to 43.6±9.1 cm/sec after TIPS (p<0.05). The hepatic artery peak systolic velocity increased from 77±51 cm/sec before TIPS to 119±53 cm/sec after the procedure (p=0.029). Conventional duplex and color Doppler ultrasound proved to be a useful non-invasive diagnostic method to assess patients who have undergone TIPS. We propose its use as the primary diagnostic modality in these patients.     

Intra-arterial Doppler flowmetry in the superficial femoral artery following angioplasty

The aim of the study was to assess the diagnostic value of an intravascular Doppler guidewire in patients with peripheral percutaneous angioplasty (PTA). The prognostic value was also evaluated. Measurements were done prior and following angioplasty in 22 patients with peripheral arterial occlusive disease. As additional therapy, stent insertion and peripheral (Aa. poplitea Ill/tibial) angioplasty was performed (4 patients per group). For stress testing, adenosinetriphosphate (ATP) was given intra-arterially. Follow-up was performed by angiography, colour-coded duplex ultrasound or judged by unequivocal clinical stage at follow-up to 13 months. Average (APV) and maximal peak velocity (MPV) increased following PTA, after additional treatment (peripheral PTA or stent), and after intra-arterial application of a vasodilator. Patients with peripheral lesions had markedly lower velocities prior treatment and following PTA after vasodilatation. Following peripheral PTA, the values were similar to the patients with PTA alone. Velocities after stenting were markedly increased in the stress condition. Of the 22 patients, 7 had a recurrent disease. The latter patients had higher velocities at rest prior to and following PTA. In stented lesions higher velocities seem to be linked with a worse outcome. The ratio between velocity prior to and after the application of the vasodilator seems to be of diagnostic importance. A ratio of 1.9 or more was of positive prognostic value. The Doppler guidewire is a practical and valuable tool in assessing technical success after angioplasty of peripheral lesions, critical or morphologically worse lesions. In our study the decision for stent application was made on the morphological image; however, increased velocity and changes in phasicity substantiated our decisions. Increased ratios prior to and after vasodilation (flow reserve) are of prognostic value and therefore suitable as indication for stent placement or tibial angioplasty. Received: 6 April 1998; Revised: 9 December 1998; Accepted: 24 June 1999     

经颈内静脉肝内门体分流术治疗肝硬化门脉高压140例分析

目的探讨经颈内静脉肝内门体分流术（TIPS）治疗肝硬化门脉高压的疗效及安全性。方法回顾性分析140例经TIPS治疗肝硬化门脉高压患者的临床资料,记录术前术后门静脉压力、门静脉和脾静脉直径、食道胃底静脉、腹水的变化,观察术后肝性脑病、复发出血、支架再狭窄等并发症。结果手术成功率及即刻止血率100%,门静脉压力术前（44.7±3.5）cmH2O,术后（23.6±3.8）cmH2O（P<0.01）,门静脉主干直径术前（1.64±0.035）cm,术后（1.27±0.047）cm（P<0.01）,脾静脉直径术前（1.26±0.027）cm,术后（0.95±0.023）cm（P<0.01）。肝性脑病发生率13.6%（19/140）,腹水好转率89%（65/73）,术后12个月复发再出血8.6%（12/140）,支架再狭窄15.7%（22/140）。结论 TIPS是治疗肝硬化门脉高压的有效方法,能有效降低门静脉压力,控制上消化道出血。     

Increase in hepatic arterial blood flow after transjugular intrahepatic portosystemic shunt creation and its potential predictive value of postprocedural encephalopathy and mortality.

PURPOSE: To determine (i) whether there is a significant increase in hepatic artery blood flow (HABF) after transjugular intrahepatic portosystemic shunt (TIPS) creation and (ii) whether the extent of incremental increase in HABF is predictive of clinical outcome after TIPS creation. MATERIALS AND METHODS: Prospective, nonrandomized, nonblinded duplex Doppler ultrasound (US) examinations were performed on 24 consecutive patients (19 men; Child Class A/B/C: 4/12/8, respectively) with a mean age of 52.8 years who were referred for TIPS creation for variceal bleeding. Peak hepatic artery velocity and vessel dimensions were used to calculate the hepatic arterial blood flow (HABF) before and after TIPS creation. Patients were clinically followed in the gastrohepatology clinic and TIPS US surveillance was performed at 1 and 3 months to assess shunt function. The extent of incremental increase in HABF was analyzed as a predictor of post-TIPS encephalopathy and/or death. RESULTS: The technical success rate of TIPS creation was 100%. The shunt diameters were either 10 mm (n = 11) or 12 mm (n = 13). TIPS resulted in a significant reduction in the portosystemic gradient from 24.3 mm Hg +/- 5.7 to 9.3 mm Hg +/- 2.9 (P <.001). The hepatic artery peak systolic velocity and HABF increased significantly after TIPS creation, from 60.8 cm/sec +/- 26.7 to 121 cm/sec +/- 51.5 (P <.001) and from 254.2 mL/min +/- 142.2 to 507.8 mL/min +/- 261.3 (P <.001), respectively. The average incremental increase in HABF from pre-TIPS to post-TIPS was 253.6 mL/min +/- 174.2 and the average decremental decrease in portosystemic gradient was 15.0 mm Hg +/- 5.3, but there was no significant correlation (r = 0.04; P =.86) between the two. All shunts were patent at 30 and 90 days without sonographic evidence of shunt dysfunction. After TIPS creation, new or worsened encephalopathy developed in five patients at 30 days and in an additional three at 90 days. They were all successfully managed medically. Three patients (12.5%) died within 30 days of the TIPS procedure. The extent of incremental increase in HABF after TIPS was variable and did not correlate with the development of 30-day and 90-day encephalopathy (P =.41 and P =.83, respectively) or 30-day mortality (P =.2). CONCLUSIONS: HABF increases significantly after TIPS but is not predictive of clinical outcome. The significance of the incremental increase is yet to be determined.     

Value of Doppler sonography in revealing transjugular intrahepatic portosystemic shunt malfunction: a 5-year experience in 216 patients

OBJECTIVE: The purpose of the study was to evaluate the long-term clinical efficacy of Doppler sonography in revealing failure of transjugular intrahepatic portosystemic shunts (TIPS). SUBJECTS AND METHODS: During a 5-year period, 1192 Doppler examinations were performed in 216 patients with TIPS. No regular follow-up shunt venography was performed. Doppler examinations were retrospectively compared with the results of shunt revisions. Sonograms with negative findings were compared with the patients' clinical status so that the number of false-negative sonographic findings leading to an episode of shunt failure (recurrence of gastrointestinal bleeding or ascites) could be ascertained. Sonographic parameters assessed included diameter, velocity, flow volume, and congestion index of the portal vein; and shunt velocities. RESULTS: Doppler sonography revealed shunt occlusion in 25 of 26 angiographically proven cases (sensitivity, 96%). The combination of velocity criteria (peak intrashunt velocity > or =250 cm/sec, maximum velocity in the portal third of the shunt < or =50 cm/sec, or maximum portal vein velocity less than or equal to two thirds of the baseline value) revealed shunt stenosis in 103 of 110 cases (sensitivity, 94%). Doppler sonography missed a significant shunt stenosis that led to an episode of gastrointestinal bleeding or ascites recurrence in only seven cases. The congestion index of the portal vein showed significant differences between patent and malfunctioning shunts (p < 0.001). CONCLUSION: Doppler sonography is an effective primary imaging method for long-term follow-up of patients with TIPS.     

CDFI定量分析对绝经后子宫内膜增厚的诊断价值

目的:应用彩色多普勒超声(CDFI)观察与分析绝经后增厚子宫内膜区动脉血流参数变化与内膜病变的相关性。方法:2008年1月～2012年1月158例绝经后子宫内膜增厚并最终获得病理的患者纳入研究,完成经阴道CDFI检查,测定增厚内膜区动脉血流,分析能量图与收缩期峰值流速(PSV)、舒张末血流最低参数(EDV)和阻力指数(RI)。结果:子宫内膜癌36例,内膜区见多条异常增粗的血管,血流信号增多紊乱,CDFI显示PSV(28±5.1)cm/s,与良性病变(24.6±3.0cm/s)无明显差异;EDV为(16±3.8)cm/s,明显高于良性病变(7.3±2.5cm/s,P<0.05);血流阻力指数(RI<0.43)则明显低于良性病变(RI>0.5)。子宫内膜良性病变122例,其中31例子宫内膜息肉内膜区单根血管延伸至瘤体,CDFI显示低速高阻血流(RI>0.56);35例子宫黏膜下肌瘤内膜区显示环状血流信号,CDFI显示低速高阻血流(RI>0.5);14例子宫内膜增生反应显示内膜区血流信号呈细条状,CDFI显示低速高阻血流(RI>0.68);21例子宫内膜增生反应无血流信号。结论:均匀增厚的内膜内高阻血流的存在是诊断内膜良性病变的关键,而异常增厚内膜内舒张期增高低阻血流的存在是恶性病变的一项重要指标。通过子宫内膜血流的CDFI检测可以帮助鉴别子宫内膜病变的良、恶性。     

Transjugular intrahepatic portosystemic shunt. Experiences at a liver transplantation center

Objective: Transjugular intrahepatic portosystemic shunt (TIPS) placement is an established therapy for portal hypertension that leads to variceal bleeding or refractory ascites. We present experiences of the role of TIPS at a liver transplantation center.Material and Methods: One hundred and ten patients were referred to the Radiological Department for TIPS placement. One of the 110 patients had recurrent cirrhosis after liver transplantation with refractory ascites. Function of the TIPS was controlled with Doppler US at 1 day, 1 week, 4 weeks and 4 months after TIPS placement and subsequently every 3 months. Shunt insufficiency was supposed when the blood flow velocity within the stent tract was under 50 cm/s and was an indication for TIPS revision.Results: TIPS was placed in 101 patients. After TIPS placement, 10 patients underwent liver transplantation. While waiting for the new liver, none of them developed variceal rebleeding, ascites or other complications of portal hypertension. Two of the 101 patients had episodes of rebleeding. The frequency of patients undergoing TIPS revision within the first year after TIPS placement was 67.5%, within the second year 38.0% and within the third year 24.4%. The revisions led to sufficient reduction of the portosystemic pressure gradient.Conclusion: In some liver transplant candidates, TIPS can be useful in minimizing the risk of complications of portal hypertension during the waiting time for a liver transplantation. TIPS can be monitored by Doppler US and revised if occlusion occurs.     

Quantitative perfusion imaging with pulsed arterial spin labeling: a phantom study.

PURPOSE: Pulsed arterial spin labeling (PASL) is a magnetic resonance (MR) method for measuring cerebral blood flow. Although several validation studies for PASL in animals and humans have been reported, no reports have detailed the fundamental study of PASL using a flow phantom. We compared the true and theoretical flow rates in a flow phantom to confirm the analytical validity of quantitative perfusion imaging with Q2TIPS sequence. METHODS: We built a flow phantom consisting of a 40-mm diameter plastic syringe filled with plastic beads and small plastic tubes 4 mm in diameter. Gd-DTPA-doped 8L water solution (0.1 mM) was circulated between the syringe and a tank through a plastic tube by a constant flow pump while the flow rate was adjusted between 0 and 2.61 cm/s. Q2TIPS sequence parameters were TI(1)=50 ms and TI(2)=1400 ms. Five imaging slices of 50 subtraction images were acquired sequentially in a distal-to-proximal direction using a single-shot echo planar imaging (EPI) technique. The theoretical flow rate calculated based upon the previously reported kinetic model for Q2TIPS was compared with the true flow rate. RESULTS: A good linear relationship was observed between the theoretical, F', and true flow rates, F, in a flow rate range of 1.43 to 1.95 cm/s (F'=1.024*F-1.915, R(2)=0.902). The ratio of theoretical to true flow rate was 92 (+/-) 4%. CONCLUSION: Flow rate was quantified with reasonable accuracy when the entire amount of labeled bolus within the phantom could be recovered. Our experiment confirmed the analytical validity of Q2TIPS and suggested that blood flow measurement may be feasible using the Q2TIPS pulse sequence and kinetic model of the PASL equation.