Sonography of transjugular intrahepatic portosystemic shunts

Transjugular intrahepatic portosystemic shunting (TIPS) is an effective procedure for relieving portal hypertension. Sonography can usefully assist portal vein puncture. Color and duplex sonography after TIPS demonstrates changes in hepatic vascular hemodynamics, detects complications, and confirms shunt patency. A large proportion of shunts will develop progressive stenosis over 12 months. Stenosis occurs because of pseudointimal hyperplasia in the stent or in the hepatic vein. Patent shunts are characterized by velocities in excess of 70 cm/s and hepatofugal flow in the portal circulation distal to the shunt. Although the cause of the stenosis can rarely be seen, velocities of less than 50 cm/s indicate shunt stenosis. Loss of cardiac pulsatility is another useful sign of shunt stenosis. Regular sonographic monitoring reliably detects stenosis, allowing stent revision and preventing recurrence of bleeding.     

Doppler evaluation of transjugular intrahepatic portosystemic shunts

Transjugular intrahepatic portosystemic shunts are becoming an increasingly popular technique for the treatment of portal hypertension and its complications. However, to maintain patency, revisions are periodically required to treat stenosis and thrombosis. At many centers, Doppler sonography is used for routine follow-up. A variety of hemodynamic parameters, including main portal vein velocity, maximum stent velocity, minimum stent velocity, velocity gradient in the stent, temporal changes in stent velocity, flow direction in the intrahepatic portal and hepatic veins, and pulsatility of flow in the stent can be used. Many studies have confirmed that Doppler sonography is a valuable, noninvasive means of detecting stent malfunction, although the criteria vary somewhat at different institutions.     

Helical CT angiography of transjugular intrahepatic portosystemic shunts

Shunt dysfunction due to draining hepatic vein and/or stent stenosis is a common long-term complication of transjugular intrahepatic portosystemic shunts (TIPS). Currently, Doppler sonography is the preferred modality for routine screening of TIPS for the detection of these complications. However, this method is time-consuming, highly operator-dependent, and difficult to perform because of the anatomic attributes of the cirrhotic liver. The use of helical CT angiography (HCTA) for imaging TIPS has been recently described. HCTA of TIPS is performed after a rapid i.v. injection of a bolus of low osmolality contrast medium, followed by helical data acquisition of the region of the shunt using thin sections. The data are then reprocessed a overlapping intervals and various reformations are obtained. Preliminary reports show the sensitivity and specificity of the helical CT angiography to be comparable with Doppler sonography.     

Intrahepatic portosystemic venous shunts: Color Doppler sonography

Background The aim of the study was to evaluate intrahepatic portosystemic venous shunts (IPSVS) patterns and to determine the role of Color Doppler sonography in the diagnosis and evaluation of related hemodynamic changes in portal perfusion. Methods Sonography and Color Doppler imaging were performed in nine patients with IPSVS. Type and Doppler waveform of the shunt were determined; velocity measurements in the portal trunk and portal branches were studied to evaluate the effects of the shunt on intrahepatic circulation. Computed tomography was performed in six patients, magnetic resonance imaging in three patients, and angiography in two patients. Results The shunt between the portal and hepatic veins was aneurismal in six patients, while localized peripheral shunt with multiple tortuous vessels in one hepatic segment was observed in three patients. The shunts showed continuous low velocity spectral tracings and in the aneurismal shunts a low velocity bi-directional or helicoidal flow was detected. The feeding portal branches and the draining hepatic veins showed anomalous Doppler tracings and alterations of intrahepatic portal perfusion were observed in three cases. Conclusion Color Doppler is essential for proper diagnosis of IPSVS and for evaluation of related hemodynamic changes in portal perfusion.     

Color Doppler sonography in the diagnosis of neonatal intrahepatic portosystemic shunts

Intrahepatic portosystemic shunts are infrequent in children. We report 3 cases of neonates who presented with jaundice during the first month of life. Color Doppler sonography in the first 2 cases showed direct communication between the right portal and hepatic veins. Both infants were asymptomatic, and the shunts disappeared spontaneously. The third case involved several shunts and an aberrant medial portal vein. This patient developed heart failure and died after surgery. Color Doppler sonography was useful in the diagnosis and follow-up of the shunts in all 3 cases.     

Ultrasound detection of unusual spontaneous portosystemic shunts associated with uncomplicated portal hypertension

Seven cases of unusual spontaneous portosystemic shunts observed by ultrasonography in the last 8 months are reported, including cases of coronary vein varicocele and patent umbilical vein; two cases of spleno-retroperitoneal anastomosis; omphalo-ilio-caval anastomosis; superior mesenteric vein-inferior vena cava anastomosis; spleno-renal anastomosis; and spleno-portal anastomosis and anastomosis from the splenic vein to the abdominal wall. One of these collateral vessels was also analyzed by pulsed Doppler flowmetry. The patients were either cirrhotic or had pre-hepatic portal hypertension (resulting from chronic pancreatitis) and gave no history of gastrointestinal bleeding or ascites. Two of these patients had previously undergone surgery for problems associated with cholestasis. In both cases, presurgical sonographic studies were used to guide the surgical procedures in the hope of preserving the anomalous connections. Furthermore, ultrasound detection of spontaneous portosystemic shunts was an important factor in interpreting the clinical symptoms of these patients.     

Color and pulsed Doppler ultrasound findings in normally functioning transjugular intrahepatic portosystemic shunts.

OBJECTIVE: To evaluate blood flow changes inside normally functioning transjugular intrahepatic portosystemic shunts (TIPS), using color Doppler ultrasound (CDUS) and pulsed Doppler ultrasound (PDUS). METHODS: A total of 72 patients (mean age 54, range 36-78 years) underwent TIPS placement, portal angiography, CDUS and PDUS examinations. Measurements inside the stent were taken at the portal side, at the central part and at the venous end of the TIPS. RESULTS: In well functioning TIPS the mean peak velocity (PV) on the portal side was 37 m/s (range 22-65 cm/s), in the area of the incoming intrahepatic portal branch the mean PV was 59 cm/s (range 40-95 cm/s) and at the side of the incoming hepatic vein the mean PV was 135 cm/s (range 88-220 cm/s). In the punctured hepatic and portal veins the mean PV was 25 cm/s (range 15-30 cm/s) and 18 cm/s (10-22 cm/s), respectively. The flow increase from the portal to the mid part (P less than or = 0.001) and to the venous side was statistically significant (P less than or = 0.001). CONCLUSION: A velocity gradient between the portal and the venous side of a TIPS is a normal finding caused by branches of the portal and hepatic vein joining the TIPS from the side and it is characteristic of a normally functioning TIPS.     

合并不同临床症状的婴幼儿先天性门体分流2例并文献复习

目的：探讨婴幼儿先天性门体分流（congenital portosyetemic shunts,CPS）的影像学表现、临床特点、相关实验室检查及治疗方案,以进一步提高临床及放射科医生对CPS的认识。 方法：回顾性分析本院两例因不同症状入院,而后被同时确诊为CPS患儿的流行病学资料、临床特点、影像学表现及相关实验室检查结果并复习总结相关文献。 临床资料：病例1：患儿男,10个月,主因“先天性心脏病伴咳嗽、发热”入院,入院后查体未发现明显异常体征,心脏未闻及杂音,结合超声心动图检查诊断为“先天性心脏病-房间隔缺损（中央型）”,此外实验室检查提示患儿碱性磷酸酶明显升高、轻度肝损害伴直接胆红素及间接胆红素升高,且以直接胆红素升高为主,查腹部B超提示“第二肝门处粗大血管,建议进一步检查”,而后进一步行腹部CT平扫及增强提示“门静脉左支与下腔静脉间异常粗大血管相沟通;门静脉主干略增宽伴门静脉右支分支稀少”,最终经数字减影血管造影（Digital Subtraction Angiography,DSA）检查证实为Ⅱa型CPS。病例2：患儿男,3岁。因“发现尿检异常2月余”入院。入院后相关检查示：尿常规：SG 1.008,PH 6.5,BLD 2+,YS黄色;镜检：RBC 2+/HP;电解质及肝肾功能大致正常。CTA检查示：脾静脉增粗,走行迂曲,脾静脉与左肾静脉间可见两条异常沟通静脉,较粗大者管径约1.3cm。DSA检查最终证实门静脉及肝内分支发育良好,脾静脉发出两条分流道分别连接至左肾静脉,为Ⅱc型CPS（图2）。本报道中两例患儿年龄较小,其中一例合并的症状比较罕见,目前报道较少,且两例患儿均行CT及DSA检查,最终均得到准确分型,且病例二的患儿及时行介入栓塞封堵治疗,使患儿得到及时有效的治疗。此外本文还进一步讨论了其相关的发病机制、相关的先天性畸形及治疗方案。 结论：CPS是一种罕见的肝血管畸形,其临床表现根据分流口位置的不同而有所变化。当肝门静脉灌注不足时,则可进一步导致肝功能受损及代谢异常。而当分流口位于肠系膜静脉、胃静脉或脾静脉并且与肾静脉发生异常沟通时则会引起肾小球肾炎、血尿、蛋白尿及结石等症状。此外其也可合并先天性心脏病、先天性胆道闭锁及皮肤血管瘤等先天性畸形。因此,临床上发现伴有肝功能异常、尿检异常和/或相关先天性畸形的患儿尤其是婴幼儿时,应提高警惕,及早行相关检查并进行分型,从而争取及时有效的治疗机会,减少相关并发症的发生。     

先天性肝内门体分流的彩色多普勒超声和超声造影模式研究

目的 探讨先天性肝内门-体静脉分流(IPSVS)的彩色多普勒和超声造影表现.方法 对19例经CT血管成像证实的先天性IPSVS患者行常规超声和超声造影检查,记录造影剂到达肝动脉时间(HAAT)、到达门静脉时间(PVAT)及到达肝静脉时间(HVAT),计算造影剂从肝动脉到达肝静脉间隔时间(HA-HVTT)和门静脉到达肝静脉间隔时间(PV-HVTT).结果 病变的特征基于Park分型进行归类,彩色多普勒超声显示门静脉分支和肝静脉或下腔静脉之间的异常交通,脉冲多普勒显示分流门静脉出现类似于肝静脉起伏的三相波形.超声造影在门脉相显示门静脉分支和肝静脉或下腔静脉之间的异常交通血管,而且HVAT、HA-HVTT、PV-HVTT缩短,与肝硬化组及正常组比较差异均有统计学意义(P＜0.01).结论 先天性IPSVS是罕见的血管异常,通常无症状,超声是诊断先天性IPSVS有效的工具,超声造影可为先天性IPSVS的诊断和鉴别诊断提供依据.     

Color Doppler sonographic evaluation of spontaneous portosystemic shunts and inversion of portal venous flow in patients with cirrhosis

PURPOSE: The aim of the study was to evaluate the usefulness of color Doppler sonography in the detection of spontaneous portosystemic shunts and abnormal blood flow direction in the portal vein in patients with cirrhosis. METHODS: Patients were 67 men and 42 women (mean age, 53 +/- 14 years) with cirrhosis confirmed by liver biopsy. All patients underwent abdominal gray-scale and color Doppler sonographic evaluations to detect the presence of spontaneous portosystemic shunts and to analyze portal vein blood flow direction. RESULTS: Spontaneous portosystemic shunts were found in 41 patients (38%), most often as splenorenal shunts (21%) and patent umbilical veins (14%). Less frequent were gastric collaterals, gallbladder varices, collaterals to thrombotic portal veins, mesoiliac shunts, and portorenal shunts to the right kidney. The presence of shunts was associated with that of esophageal varices (p < 0.01), ascites (p < 0.01), and inversion of portal flow (p < 0. 001) but not with splenomegaly. The direction of portal venous flow was normal (hepatopetal) in 80 patients (73%), hepatofugal in 10 (9%), and bidirectional in 7 (6%); 12 patients (11%) had partial portal vein thrombosis. CONCLUSIONS: Portosystemic shunts and the direction of portal venous flow are important features in the sonographic diagnosis of portal hypertension.     

Incidence and clinical significance of spontaneous intrahepatic portosystemic venous shunts detected by sonography in adults without potential cause

PURPOSE: B-mode and color Doppler sonography were used to assess the incidence and clinical significance of spontaneous intrahepatic portosystemic venous shunt in adults without detectable cause. METHODS: A total of 25,579 adults without potential cause of intrahepatic portosystemic venous shunt were screened using B-mode sonography. Suspicion of shunt was confirmed by color Doppler sonography. Patients with shunt were followed up with sonography at 6- to 12-month intervals and received dietary education to prevent the ingestion of extra-large amounts of protein. During each sonography session, the patients were asked to report any experience of consciousness disturbance. RESULTS: Six patients (0.0235%) showed evidence of shunt on color Doppler sonography. Direct communication between a right portal branch and the inferior vena cava was found in 3 patients; a small aneurysm connecting a peripheral portal branch to the hepatic vein was found in the remaining 3 patients. Five patients were followed up (range, 12-60 months) and showed no change in the size of the shunt. None of the patients with shunt reported an experience of consciousness disturbance. CONCLUSIONS: The incidence of spontaneous intrahepatic portosystemic venous shunt is extremely low in asymptomatic adult patients. Follow-up and dietary control seen to be suitable for their management.     

Cavernous hemangioma with arterioportal and portosystemic shunts: precise diagnosis with dynamic multidetector computed tomography imaging

Cavernous hemangiomas with shunt formations have been a recently recognized entity. Arterioportal (AP) shunts with cavernous hemangiomas have been described. However, a combination of AP and portosystemic (PS) shunts causing portal hypertension has not been previously demonstrated by computed tomography (CT) imaging. In this study, we report an atypical cavernous hemangioma associated with portal hypertension. Cavernous hemangioma with AP and PS shunts formations was precisely demonstrated with dynamic multidetector CT imaging.