Stenosis of transjugular intrahepatic portosystemic shunts: presentation and management

OBJECTIVE

The purpose of this study was to define the incidence, nature, and presentation of stenoses that develop in patients with transjugular intrahepatic portosystemic shunts (TIPS) and to assess the efficacy of treatment that prolongs shunt patency.

MATERIALS AND METHODS

TIPS were successfully created in 108 patients over a 43-month period. Of the 93 patients with adequate radiologic or pathologic follow-up, 60 had no shunt problems and 33 developed shunt stenoses or occlusions. Follow-up of these 93 patients included sonography, venography, and/or pathologic confirmation. Presentations of stenoses, types of therapy, and patency after treatment were evaluated in all patients.

RESULTS

In the cohort group, 35% of the patients had shunt problems (mean time to presentation, 7.4 months after TIPS). Forty stenoses and eight occlusions occurred in the 33 patients. Of the 48 shunt problems, 35 (73%) were detected with routine radiologic screening, 12 (25%) presented with recurrent symptoms, and one (2%) was confirmed by pathologic evaluation. Of the 33 patients with stenoses and occlusions, 21 had one reintervention, six had two reinterventions, three had three reinterventions, one had four reinterventions, and two received no therapy. These reinterventions included 30 restentings, 11 angioplasties, four new shunts, and one thrombolysis alone. Of the 31 primary reinterventions, 23 (74%) were restentings, six (19%) were angioplasties, and two patients received a new TIPS. Of the 10 secondary reinterventions, six were restentings, three were angioplasties, and one was a new TIPS. Of the four tertiary reinterventions, one was a restenting, two were angioplasties, and one was thrombolysis. Kaplan-Meier survival analysis revealed the primary patency of the shunt to be 67% at 6 months, 48% at 1 year, and 26% at 2 years. The primary-assisted patency of the shunt was 96% at 6 months and 87% at 3 years. The secondary patency was 99% at 1 year and 89% at 3 years.

CONCLUSION

Stenoses are common after TIPS procedures and frequently can be detected on routine screening studies. Shunt revision can effectively extend the patency of TIPS. Restenting is generally required for hepatic vein stenoses. Angioplasty should be the first line of therapy for intrashunt stenoses, as only 44% of patients will require restenting.

Autologous vein-covered stent for the endovascular management of an iliac artery-ureteral fistula: case report and review of the literature

Iliac artery-ureteral fistula is a rare entity that is being reported with increasing frequency. Patients with iliac artery-ureteral fistulas can be divided into two distinct groups on the basis of the factors that predispose them to having these fistulas. In group I the fistula is associated with degenerative iliac artery disease or previous arterial reconstructive surgery. Patients in group II have undergone some combination of the following procedures: pelvic extirpative surgery for malignancy, urinary diversion, radiation therapy, and ureteral stenting. The diagnosis of an iliac artery-ureteral fistula can be elusive even with the use of multiple imaging methods. Direct operative repair is technically demanding and is associated with high mortality rates. In recent years, treatment has shifted toward percutaneous embolization of the iliac artery and extraanatomic lower extremity vascular reconstruction for group II patients. In this report, the 24 group II patients with iliac artery-ureteral fistulas who previously have been described are reviewed, and a new endovascular treatment for this entity that uses a stented vein graft is detailed.

Comparison of portal vein anatomy and bony anatomic landmarks

PURPOSE

To determine if a relationship exists between the right portal trunk (RPT) and bony structures that might aid guidance of needle passes into the RPT during transjugular intrahepatic portosystemic shunt (TIPS) placement.

MATERIALS AND METHODS

Sixty-two TIPS portal venograms were reviewed. The distance of the mid-RPT from the lateral margin of the vertebral column was measured and calculated as a fraction of the adjacent vertebral body width. The cephalocaudal height of the RPT was compared with that of the posterior ribs and rib spaces. The cephalocaudal height was evaluated with frequency distribution, and scattergram plots were used to determine the most common location of the mid-RPT relative to bony structures. The height and lateral position were analyzed in relation to clinical parameters to determine the effect of these parameters on RPT position.

RESULTS

The mean distance of the mid-RPT from the lateral vertebral margin was 0.9 vertebral widths (range, 0.1-1.5). Fifty-six of 62 (90%) mid-RPTs were between 0.5 and 1.5 vertebral widths to the right of the lateral margin of the vertebrae. Fifty-four of 62 (87%) mid-RPTs were below the 10th and above the 12th ribs. Clinical factors did not affect RPT position.

CONCLUSION

Bony landmarks provide an approximation of the mid-RPT location and may aid in TIPS placement.

Nonsurgical management of gastric or duodenal perforation from a Wills-Oglesby-type gastrostomy tube

PURPOSE

To describe the clinical and radiologic appearance of gastrointestinal perforation related to a Wills-Oglesby-type gastrostomy tube, as well as techniques for nonsurgical management.

MATERIALS AND METHODS

Five patients with a previously placed 14-F modified Wills-Oglesby-type gastrostomy catheter experienced viscus perforation by the distal limb of the catheter during a 30-month period.

RESULTS

The average interval between tube placement and perforation event was 4.3 months. Three patients had migration of the gastrostomy tube into the duodenum and subsequent duodenal perforation. One patient had posterior perforation of the stomach, and one patient developed a gastrocolic fistula. Generalized peritonitis was not present in any patient. All patients were treated successfully without surgery, and tube feedings were re-established in 4-14 days.

CONCLUSIONS

Gastrostomy tube-related perforation is an uncommon, delayed complication of percutaneous gastrostomy with the modified Wills-Oglesby-type catheter. Nonsurgical management is feasible in select instances. Because of these gastrointestinal perforations, the gastrostomy tube has been modified (eliminating the distal tip), and no gastrostomy-associated gastrointestinal perforation has been experienced since.

Percutaneous gallstone removal: long-term follow-up

PURPOSE

To evaluate gallstone and symptom recurrence rates, long-term complications, and life expectancy after percutaneous gallstone removal.

PATIENTS AND METHODS

Medical records of 87 patients (mean age, 69 years +/- 14 [standard deviation]) undergoing percutaneous gallstone removal between 1987 and 1992 were reviewed. Physicians and patients (or their families) were contacted for clinical follow-up. Thirty-one patients returned for follow-up ultrasound (US).

RESULTS

The final study group consisted of 65 patients. Mean survival from the time of initial gallbladder drainage was 33 months +/- 19. Over a mean clinical follow-up period of 33 months, eight of 65 patients (12%) developed recurrent symptoms; six of these eight had recurrent gallstones shown at US. Of 30 patients with technically adequate US images (mean follow-up, 14 months +/- 12), 12 (40%) had recurrent gallstones. Six of these 12 patients had recurrent symptoms. No long-term complications were identified.

CONCLUSION

The risk of gallstone recurrence after percutaneous removal is notable, but the symptom recurrence rate is much lower. Percutaneous gallstone removal is beneficial for patients at prohibitive surgical or general anesthetic risk.

Evaluation of coagulation tests as predictors of angiographic bleeding complications

PURPOSE

To determine whether prothrombin time (PT), partial thromboplastin time (PTT), and platelet count are useful predictors of postangiographic hematoma.

MATERIALS AND METHODS

The authors prospectively studied 1,000 consecutive patients who underwent femoral arterial puncture for a diagnostic or therapeutic vascular procedure. Demographic and procedural variables were recorded, including patient age and sex, history of medications and bleeding, procedure type and length, catheter size, and experience level of radiologist applying compression for hemostasis.

RESULTS

Abnormal results of coagulation tests were not correlated with an increased occurrence of hemorrhagic complications, but bleeding complications did occur more often in patients with thrombocytopenia. Hematomas occurred in 8.1% (10 of 123) of patients with any abnormal coagulation test results and 9.7% (85 of 877) of patients with normal test results. A platelet count of less than 100 X 10(9)/L was correlated with a higher occurrence of hematoma (P = .002).

CONCLUSION

Abnormal PT and PTTs do not correlate with an increased risk of postangiographic hematoma, but a low platelet count is associated with more bleeding complications.

Prospective anatomic study of the inferior vena cava and renal veins: comparison of selective renal venography with cavography and relevance in filter placement

PURPOSE

To compare the sensitivity of selective renal venography with that of cavography in the detection of variant anatomic structures of the renal vein that may affect the placement of inferior vena caval (IVC) filters and to define IVC dimensions.

PATIENTS AND METHODS

Flush cavography, selective bilateral renal venography, and bilateral iliac venography were performed in 108 patients referred for IVC filter placement or vena cavography. Infrarenal IVC length and width were determined with a sizing catheter during cavography. Anomalies were considered significant if they altered placement or selection of the vena cava filter or if they represented a potential collateral pathway for clot to bypass a filter.

RESULTS

Variant anatomic structures in the renal vein were found in 11% of patients with cavography and in 37% of patients with selective renal vein injection. Detected anomalies included circumaortic veins (n = 11), multiple veins (n = 25), retroaortic veins (n = 2), and a partially duplicated IVC (n = 1). Selective venography depicted anomalies not suspected at standard cavography in 28 cases (26%); in 20 cases (18% of population) they were significant. The average infrarenal width was 20 mm on the anteroposterior view and was 17 mm on the lateral projection.

CONCLUSION

IVC anomalies are common, and selective renal venography can depict significant anomalies in renal vein anatomic structures not shown at standard cavography.

Multicenter investigation of the role of transjugular intrahepatic portosystemic shunt in management of portal hypertension

PURPOSE

To determine the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) placement, a prospective multicenter trial was undertaken.

MATERIALS AND METHODS

In eight institutions, 96 patients underwent TIPS placement after failed sclero-therapy (Child-Pugh class A [n = 24], class B [n = 38], and class C [n = 34]), with follow-up for 6 months (with ultrasonography and angiography and clinical and laboratory studies).

RESULTS

TIPS placement was successful in all patients (mean initial portosystemic pressure gradient, 22.8 mm Hg + 6.7 [standard deviation]; mean decrease after placement, 12.8 mm Hg + 5.2), with variceal embolization in 25 patients. Complications included liver capsule puncture (n = 12), hepatic artery puncture (n = 3), main portal vein puncture (n = 1), and increased encephalopathy (n = 28). The 30-day mortality rate was 0% for patients with Child class A disease, 18% for class B, and 40% for class C. At 6 months, primary patency was 88% and assisted patency was 94%.

CONCLUSION

The risk associated with TIPS placement is reasonable, and it is an effective procedure for the treatment of portal hypertension.

Accuracy of DSA in the evaluation of patency of infrapopliteal vessels

PURPOSE

To evaluate the accuracy of intraarterial digital subtraction angiography (DSA) in the demonstration of patent infrapopliteal vessels.

PATIENTS AND METHODS

One-hundred sixty-five arteriograms were obtained in 153 consecutive patients prospectively enrolled to evaluate lower extremity ischemia. In 86 cases a follow-up angiogram of the infrapopliteal vessels was obtained during surgery or after endovascular intervention (n = 57). Twenty-nine arteriograms were followed by surgical exploration of the infrapopliteal vessels. Standard angiographic technique was performed with intraarterial DSA of the most symptomatic foot. Visualization of distal vessels was compared with intraoperative or postintervention imaging or with the results of surgical exploration.

RESULTS

Of the 57 procedures after which either intraoperative or post-endovascular intervention angiography was performed, DSA results were equivalent in 47 (82%) and worse in five (9%). When individual vessels were evaluated, the sensitivity of DSA in the identification of patent named vessels was 95%, and the specificity was 92%. Among 29 cases with a surgical standard of reference, 28 patients underwent bypass to a vessel correctly identified as patent at DSA; one patient was incorrectly identified as having no patent named vessels.

CONCLUSION

Intraarterial DSA is accurate and reliable in the assessment of patency in infrapopliteal vessels before surgery or endovascular intervention in patients with infrainguinal atherosclerotic disease.

Evaluating peer reviews. Pilot testing of a grading instrument

OBJECTIVE

To measure the reliability and preliminary validity of a grading instrument for editors to evaluate the quality of peer reviews.

DESIGN

The consecutive sample design included 53 reviews of 23 manuscripts. Reviews were systematically assigned to interrater reliability (n = 41; power greater than 0.90 to detect a difference of greater than one point) and preliminary criterion-related validity (n = 12) subsamples. Content validity was closely examined.

SETTING

Nonclinical.

PARTICIPANTS

Three graders evaluated reliability. One individual examined content validity and two editors tested preliminary criterion-related validity. INTERVENTION (INSTRUMENT)--Attributes reflecting two basic dimensions, review content and format, were identified and scored (values are possible points/percent contribution): timeliness, 3/21%; grade sheet, 1/7%; etiquette, 1/7%; sectional narratives, 3/21%; citations, 2/14%; narrative summary, 2/14%; and insights, 2/14%. A scoring guide was provided.

MAIN OUTCOME MEASURES

Statistical analyses used to test the interrater reliability of the total score included the intraclass correlation coefficient and analysis of variance with the expectation to uphold the null hypothesis. Kendall's coefficient of concordance was used to test preliminary criterion-related validity.

RESULTS

The intraclass correlation coefficient was .84 (P < .001) and a lack of difference between mean scores was demonstrated by analysis of variance (P = .46). Content validity was confirmed and preliminary criterion-related validity was indicated (Kendall's coefficient of concordance = .94, P = .038).

CONCLUSIONS

The instrument is reliable. Content validation has been completed, and further criterion-related validation is warranted.

Angiographic evaluation and therapy of ureteroarterial fistulas

OBJECTIVE

Fistulas between the iliac artery and the ureter are extremely uncommon, life-threatening conditions usually seen in patients who have had pelvic irradiation or have indwelling ureteral stents. We describe our experience in the angiographic evaluation and therapy of these fistulas.

MATERIALS AND METHODS

We retrospectively reviewed medical records for diagnoses of ureteroarterial fistulas. Patients' records were evaluated for potentially associated etiologic factors, clinical features and course, radiographic evaluation and findings, and therapy.

RESULTS

Our review showed that four patients treated at our institution (all since 1990) had ureteroarterial fistulas. All four patients had indwelling ureteral stents and had had irradiation for pelvic cancer. Three had spontaneous brisk hemorrhage in the urinary tract. The fourth had hemorrhage after balloon dilatation of a ureteral stricture. Initial diagnosis was based on findings on iliac arteriography in three patients and on findings on retrograde ureterography in one. Angiographic techniques required to visualize the fistulas included selective arterial catheterization, use of multiple projections, and provocative maneuvers. Treatment of the ureteroarterial fistulas involved surgery in one case, isolated embolotherapy in one case, and a combination of embolotherapy and surgery in two cases.

CONCLUSION

Specific angiographic maneuvers are often required to identify ureteroarterial fistulas. Transcatheter embolotherapy (with or without surgical bypass) is an effective form of treatment for this rare abnormality.

Peripheral vascular disease: evaluation with stepping DSA and conventional screen-film angiography

PURPOSE

To prospectively evaluate stepping digital subtraction angiography (S-DSA), which enables peripheral digital subtraction angiography (DSA) of both lower extremities after one injection of contrast material, in comparison with conventional screen-film angiography (SFA) for evaluation of lower-extremity vascular disease.

MATERIALS AND METHODS

Fifty consecutive patients were prospectively examined. Each study was performed without knowledge of the findings in the other. Additional stationary DSA images were obtained whenever necessary. All studies were individually evaluated for diagnostic adequacy and then side by side for vascular opacification, timing of contrast enhancement, ease of reading, and overall superiority.

RESULTS

The diagnostic adequacy of S-DSA was not statistically different from that of SFA (P > .30). SFA was subjectively considered superior in opacification (P < .003), ease of reading (P < .003), and subjective overall superiority (P < .005). S-DSA was superior in timing of contrast enhancement (P < .001).

CONCLUSION

The advantages of S-DSA can be achieved while the diagnostic adequacy of SFA is maintained. However, SFA was considered superior in three of four subjective characteristics.

Interventional radiologic placement of Hohn central venous catheters: results and complications in 100 consecutive patients

PURPOSE

Hohn catheters are single- or double-lumen catheters used for intermediate-length central venous access. The authors report their technique, results, and long-term follow-up in a prospective study of their first 100 consecutive patients.

PATIENTS AND METHODS

Indications for Hohn subclavian catheter placement included chemotherapy in 53%, antibiotic therapy in 30%, and total parenteral nutrition in 8%. Patients' ages ranged from 21 to 82 years, and 80% of catheters were placed in inpatients. Hohn catheters were placed with fluoroscopic and/or ultrasound guidance. Patients were followed up for the duration of the study or until their catheters were removed.

RESULTS

The technical success rate for catheter placement was 100%. No major procedural complications occurred. Duration of catheter placement varied between 5 and 276 days (mean, 70 days). The catheter infection rate was 8%, which corresponds to 1.1 infections per 1,000 catheter days. Catheter thrombosis occurred in nine cases (9%) and was successfully treated with urokinase in six of these nine. Subclavian vein thrombosis occurred in 3% of patients.

CONCLUSION

Technical success, complication, and long-term patency rates for the Hohn catheter are comparable to or better than those in most surgical series involving tunneled external catheters. The Hohn catheter is an excellent alternative for intermediate-length central venous access. Hohn subclavian catheter placement has become a standard part of the authors' interventional radiology service and is easily adaptable to all interventional practices.

Complications of transjugular intrahepatic portosystemic shunt: a comprehensive review

It is generally accepted that the transjugular intrahepatic portosystemic shunt (TIPS) procedure has lower morbidity and mortality rates than those of surgical shunting. Nevertheless, complications occur. The authors have reviewed their experience and that of other institutions in compiling an extensive list of complications. Complications are categorized according to those related to transhepatic needle puncture, transvenous access to the portal vein, portal venous cannulation, the stent, the puncture site, portosystemic shunting, and contrast material. Excluding hepatic encephalopathy and delayed stenosis or occlusion of the shunt, an overall complication rate of less than 10% can be expected for TIPS. The prevalence of aggravated or new cases of encephalopathy is 5%-35%, and over the long term, up to 75% of shunts may undergo stenosis or occlusion. The direct procedural mortality rate is less than 2%, and the 30-day mortality rate ranges from 4% to 45%, depending on several factors. The role to which TIPS is relegated will be influenced by the long-term success rate in the prevention of recurrent variceal hemorrhage.

Morphologic and hemodynamic findings at sonography before and after creation of a transjugular intrahepatic portosystemic shunt

OBJECTIVE

The purpose of this study was to describe the morphologic and hemodynamic findings in the hepatic vasculature before and immediately after creation of a transjugular intrahepatic portosystemic shunt.

SUBJECTS AND METHODS

We used gray-scale, duplex, and color Doppler sonography to prospectively examine 25 patients before and after percutaneous placement of a stent to create a transjugular intrahepatic portosystemic shunt. Patency and direction of flow were determined in the stent and in the main, right, and left portal veins. Flow velocity was measured in the stent and in the main portal vein.

RESULTS

In all patients, the stent was easily identified as connecting branches of the portal and hepatic veins. Three thrombosed stents were correctly detected sonographically. One stent that was thought to be thrombosed at sonography was found to be patent at angiography. Flow velocities in the patent stents ranged from 73 to 185 cm/sec (mean, 130 +/- 33 cm/sec). Mean peak velocities in the main portal vein were 20 cm/sec before stent placement and 38 cm/sec after stent placement (p < .002). In 14 patients, flow direction in the left or right portal vein was hepatofugal after the stent was placed. In two of these 14 patients, long-term follow-up showed subsequent conversion of flow in the portal vein branches from hepatofugal to hepatopetal. One of these two patients had a thrombosed stent and the other had a hepatic vein stenosis above the stent. The second patient also had a proven decrease in flow velocity in the stent at the time of stenosis.

CONCLUSION

We conclude that high flow velocities are expected in the main portal vein and in the stent immediately after the shunt is created and that flow in portal vein branches is usually hepatofugal. We recommend sonography soon after the shunt is created, so that baseline flow velocity in the stent and flow direction in portal vein branches can be established, because a subsequent decrease in flow velocity in the stent or a change in direction of flow in a portal branch may indicate stent malfunction.

Fragmentation of biliary calculi in 71 patients by use of intracorporeal electrohydraulic lithotripsy

PURPOSE

Failure of percutaneous or endoscopic removal of biliary calculi is often associated with impacted stones or stones larger than 1.5 cm. In these difficult cases, intracorporeal electrohydraulic lithotripsy (EHL) is a method that allows large stones to be fragmented and removed percutaneously or endoscopically. In this study, the authors expand their experience with EHL and further evaluate the safety and efficacy of this technique to remove biliary tract calculi.

PATIENTS AND METHODS

Intracorporeal electrohydraulic lithotripsy was used to treat 71 patients with calculi in the bile ducts (n = 35) or gallbladder (n = 36). Access was obtained by means of a surgical T-tube tract (n = 16), percutaneous transhepatic biliary drainage (n = 14), percutaneous cholecystostomy (n = 36), an intraoperative approach during common duct exploration (n = 2), and at endoscopic retrograde cholangiopancreatography (n = 3).

RESULTS

EHL lithotripsy was effective in fragmenting all biliary stones in 69 of the 71 patients (97%). All of the stone fragments were removed in 67 of these 69 patients (94%). Major complications, including bile peritonitis and gallbladder necrosis, occurred in five patients; however, all major complications were related to the initial percutaneous drainage or tract dilation. No significant complications were directly attributable to the EHL procedure.

CONCLUSION

Intracorporeal EHL is a safe and effective method that can be used to improve the success of percutaneous and endoscopic biliary calculi removal.

Fluoroscopically guided percutaneous gastrostomy in children

Percutaneous gastrostomy was performed in 27 patients with ages ranging from 7 months to 18 years (mean, 8 years). Patient weights ranged from 4.7 to 73 kg (mean, 25 kg). Access to the stomach was planned and achieved with only fluoroscopic guidance. The technical success rate was 100%. Major procedure-related complications including death, sepsis, hemorrhage, peritonitis, or early tube removal did not occur. The minor complication of local skin infection occurred in six patients. Twenty-six patients (96%) tolerated tube feedings well. Mean follow-up was 184 days, and median follow-up was 103 days. At 30 days, 26 patients (96%) were alive. Percutaneous gastrostomy under fluoroscopic guidance is a safe and effective method of obtaining long-term nonparenteral nutritional access in pediatric patients.

Transvenous retrieval of misplaced stainless steel Greenfield filters

Transvenous retrieval was attempted in five patients following surgical misplacement of stainless steel Greenfield filters. Four filters were located within the right atrium, and one was in the left hepatic vein. All retrievals were attempted within 5 days of placement. Retrieval was successful for the four filters in the right atrium and failed for the filter in the left hepatic vein. One air embolism occurred; this was the only filter- or retrieval-related complication. Transvenous retrieval is a safe and effective minimally invasive method of removing misplaced filters.