Study Of Imaging Findings And Safety Of Interventional Radiology In The Patients With Communicating Veins Originated From Upper Side Of Obstruction Of Inferior Vena Cava

Background and objectivesThe Budd-Chiari syndrome (BCS) is a heterogenous group of disorders characterized by hepatic venous outflow obstruction at the level of the hepatic veins (HVs) and/or the inferior vena cava(IVC), which results in the congestion of portal hypertension(PHT) and/or inferior vena caval hypertension(IVCHT). BCS has complex pathological types and various lesion types. The type of lesion can be roughly divided into obstruction of HVs, obstruction of IVC and mixed. The treatments of BCS went through three stages:medical therapy, surgical therapy and interventional therapy. In the recent30years, under the joint efforts of scholars from different countries, interventional therapy has replaced surgical therapy as the best choice. Especially, Professor Zu Maoheng’s breakthrough in technology of guidewire penetration, catheter thrombolysis, and coaxial guidewire penetration had reached a new height in success rate of BCS.Although interventional therapy has the merits of smaller trauma, less pain and higher security compared with surgical treatment, some serious complications or even death may occur in the duration of interventional therapy in some refractory cases.In August2004, a patient with BCS hospitalized in department of interventional radiology of the Affiliated Hospital of Xuzhou Medical College. Abdominal bleeding occurred in interventional procedure, after a covered stent was placed in IVC, the bleeding was controlled, finally, the patient recovered. This case initiated our research the reason of rupture of blood vessels. We found that some small newborn and nameless vessels originated from upper side of obstruction of IVC. We called it "dangerous communicating veins" because of its dangerous to interventional procedure.In recent years, magnetic resonance venography (MRV) has become an important screening method of diagnosis and preoperative assessment in Budd-Chiari syndrome. It is of great importance to diagnose the communicating veins preoperatively for the precaution of intra-abdominal bleeding in interventional procedure. To explore the application value of MRV in the diagnosis of communicating veins has great significance.The purpose of this research is to expore the communicating veins originated from upper side of obstruction of IVC, to investigate the display rate of communicating veins by comparative study of MRV and DSA, to propose some methods to improve the safety of interventional procedure in patients with communicating veins,Materials and methods1. Clinical datasThe study enrolled511patients who hospitaled in the Affiliated Hospital of Xuzhou Medical Collge for diagnosis BCS of obstruction of IVC from January2004to August2012.319cases of male,232cases of female, aged from5to79years old, average47±11years old, its duration is3to25years.180cases is segmental obstruction of IVC,371cases is membranous obstruction of IVC.50patients’s imagings who diagnosed with dangerous communicating veins by DSA were involved.2. Measure related data of communicating veinsMeasure the root diameter of communicating veins of single-vein type and multi-vein type, the major axis and abscissa axis of varicose tumor type. Measure the distance from the upper side of obstruction to cardio-diaphragmatic angle and the diameter of IVC at4cm below the upper side of obstruction.3. Statistical analysisAll the data are analyzed by SPSS18.0statistical package. The single-factor analysis of variance is applied to compare the diameter of IVC at4cm below the upper side of obstruction among three types. It is applied to compare the distance from the upper side of obstruction to cardio-diaphragmatic angle among three types as well. Nonparametric test is applied to compare the occurrence rate of communicating veins between patients with membranous obstruction and segmental obstruction of IVC. P <0.05is considered statistically significance.Results1. The communicating veins can be classified into three types of single-vein type, multi-vein type and varicose tumor type. The incidence of communicating veins is19.2%(106/551). Single-vein type accounts49.1%(52/106), multi-vein type accounts35.8%(38/106), varicose tumor type accounts15.1%(16/106) 2. The diameter of single-vein type is6.63mm±2.42mm, multi-vein type is4.75mm±1.77mm, the major axis of varicose tumor type is20.39mm±6.08mm and abscissa axis is14.53mm±3.36mm. The distance from the upper side of obstruction to cardio-diaphragmatic angle of single-vein type, multi-vein type and varicose tumor type is38.17mm±21.71mm,39.67mm±18.56mm,21.31mm±8.74mm, respectively. The diameter of IVC at4cm below the upper side of obstruction is20.32mm±4.21mm,18.52mm±4.27mm,19.80mm±4.46mm, respectively.The compare among three types in the distance from the upper side of obstruction to cardio-diaphragmatic angle is F=5.716, P<0.05, the difference is statistically significant.The compare among three types in the diameter of IVC at4cm below the upper side of obstruction among is F=1.977, P>0.05, the difference is not statistically significant. The compare between patients with mambanous obstruction and segmental of IVC in the occurrence rate of communicating veins is P>0.05, the difference is not statistically significant.3. DSA as the gold standard, according to the diameter of vein, the total display rate of MRV is64.8%(46/71), the display rate of0-<4mm group is25%(5/20),4-<8mm group is75%(30/40),8-<12mm is100%(11/11). According to the type, the total display rate of MRV is90%(45/50), the display rate of single-vein type is78.3%(18/23), multi-vein type is35%(7/20), varicose tumor type is100%(100/100)。4. All of the106cases were given retrograde puncture,28cases in single-vein type were given catheter mark,19cases in multi-vein type were given guidewire mark,12cases were given3D-DSA discrimination to avoid injuring the communicating veins.Conclusions1. Three types of communicating veins including single-vein type, multi-vein type and varicose tumor type can originate from the upper side of obstruction of IVC.2. The diameter of vein exceeding4mm and varicose tumor type can be accurately displayed on MRV. However, the diameter of below4mm is not so accurate.3. Methods of retrograde puncture, catheter mark, guidewire mark and3D-DSA discrimination can avoid injuring the "dangerous" communicating veins and improve safety of interventional therapy.