Long-term results of microcoil embolization for colonic haemorrhage: how common is rebleeding?

OBJECTIVE: To determine the long-term results of patients undergoing transcatheter coil embolization for the treatment of acute colonic haemorrhage. METHODS: Patients undergoing angiography for suspected colonic bleeding between January 2002 and December 2012 were reviewed (average age, 60 years; 38.4% male). Baseline, procedural and outcome parameters were recorded following the Society of Interventional Radiology guidelines. Primary outcome measures included early (<30 days) and delayed (>30 days) rebleeding events and adverse procedure-related complication. Average follow-up time was 996 days (median, 232 days; range, 30-3663 days). RESULTS: One or multiple sites of bleeding were identified in 40 cases. Coil embolization was performed in 39 patients, 26 (66.7%, 26/39) of whom were treated successfully without technical/clinical failure (n = 12) or loss to follow-up (n = 1). Three patients (11.5%, 3/26) rebled in the early period within 30 days; one patient went on to hemicolectomy. Four patients (15.3%, 4/26) experienced delayed rebleeding after 30 days; two of whom also underwent hemicolectomy. No major complication occurred. One minor complication of short segment arterial dissection was seen in the clinical failure group. One case of asymptomatic ischaemia was identified on a patient undergoing pre-operative colonoscopy for elective bowel resection. No instances of ischaemic stricture were seen. All-cause mortality of successfully treated and all patients at 1 year was 31% (8/26) and 30% (12/40), respectively. CONCLUSION: Transcatheter coil embolization is a durable treatment option with a technical and clinical success rate of 67% in the setting of acute colonic haemorrhage. A modest level of rebleeding was seen among successfully treated patients in both the early and delayed periods; in the majority of patients, embolization proved to be definitive therapy. ADVANCES IN KNOWLEDGE: Transcatheter coil embolization is a durable and potentially definitive therapy in the management of acute colonic haemorrhage.

Hemodynamics in the cephalic arch of a brachiocephalic fistula.

The care and outcome of patients with end stage renal disease (ESRD) on chronic hemodialysis is directly dependent on their hemodialysis access. A brachiocephalic fistula (BCF) is commonly placed in the elderly and in patients with a failed lower-arm, or radiocephalic, fistula. However, there are numerous complications such that the BCF has an average patency of only 3.6 years. A leading cause of BCF dysfunction and failure is stenosis in the arch of the cephalic vein near its junction with the axillary vein, which is called cephalic arch stenosis (CAS). Using a combined clinical and computational investigation, we seek to improve our understanding of the cause of CAS, and to develop a means of predicting CAS risk in patients with a planned BCF access. This paper details the methodology used to determine the hemodynamic consequences of the post-fistula environment and illustrates detailed results for a representative sample of patient-specific anatomies, including a single, bifurcated, and trifurcated arch. It is found that the high flows present due to fistula creation lead to secondary flows in the arch owing to its curvature with corresponding low wall shear stresses. The abnormally low wall shear stress locations correlate with the development of stenosis in the singular case that is tracked in time for a period of one year.

Superselective embolization of lower gastrointestinal hemorrhage: a new paradigm.

In the past 5 years, there has been a rapid evolution in the endovascular treatment of lower gastrointestinal bleeding. Previously, most bleeding distal to the ligament of Treitz was managed with catheter-directed vasoconstrictive therapy. Currently, microcatheters allow superselective embolization of bleeding vessels, a technique that minimizes potential ischemic complications and obviates many drawbacks associated with vasopressin infusion. This article summarizes the current radiologic approach for patients with severe colonic hemorrhage.

Subcutaneous chest ports via the internal jugular vein. A retrospective study of 117 oncology patients.

PURPOSE: To review image-guided chest port insertion using the right internal jugular vein as the access site of choice. MATERIAL AND METHODS: One hundred and eighteen subcutaneous chest ports were placed via the internal jugular vein in 117 patients with malignancies using both fluoroscopic and US guidance in interventional radiology suites. RESULTS: The technical success rate was 100% with no procedural complications. Follow-up was obtained in all patients with total access days of 40,450 days (mean, 342.8 days). Premature catheter removal was required in 8 patients (6.8%, 0.20 per 1,000 access days) due to non-treatable complications: 2 catheter occlusions/malfunctions (1.7%, 0.05 per 1,000 access days), 1 catheter-related skin erosion (0.85%, 0.024 per 1,000 access days), and 5 infections (4.2%, 0.15 per 1,000 access days). Two symptomatic right upper extremity venous thromboses also occurred (1.7%, 0.05 per 1,000 access days) that were treated successfully with anticoagulation. CONCLUSION: Image-guided placement of internal jugular vein chest ports has a high success rate and low complication rate compared with reported series of unguided subclavian vein port insertion. The internal jugular vein should be used as the preferred venous access site compared to the subclavian vein.

Superselective microcoil embolization of colonic hemorrhage.

OBJECTIVE: We evaluated therapeutic microcoil embolization in a group of patients with severe colonic hemorrhage. MATERIALS AND METHODS: Twenty-seven patients with severe colonic bleeding due to diverticular disease (n = 19), angiodysplasia (n = 6), cecal ulcer (n = 1), or unknown cause (n = 1) underwent attempted microcoil embolization (n = 25). Microcatheters were used in all procedures, and embolization was performed at the level of the vasa recta or the marginal artery of Drummond. Branches of the superior mesenteric artery were embolized in 12 patients, branches of the inferior mesenteric artery were embolized in 12 patients, and branches of both the superior and inferior mesenteric arteries were embolized in one patient. RESULTS: Technical success was achieved in 93% (25/27) of the procedures. However, immediate hemostasis occurred in 96% (26/27) of patients because in one failed procedure, an occlusive dissection of the inferior mesenteric artery arrested bleeding. Three patients rebled within 24 hr. One patient was treated with endoscopic cauterization, and two patients underwent right hemicolectomy. One patient who underwent right hemicolectomy for rebleeding had ischemic changes found on pathologic analysis of the resected specimen, and a second patient who underwent embolization of branches of the superior and inferior mesenteric arteries developed bowel infarction requiring left hemicolectomy. Prolonged clinical success occurred in 81% (22/27) of patients. CONCLUSION: Therapeutic microcoil embolization for severe colonic hemorrhage is an effective and well-tolerated procedure.

Comparison of balloon- and mushroom-retained large-bore gastrostomy catheters.

OBJECTIVE: We conducted a retrospective study to evaluate two different types of percutaneous fluoroscopic gastrostomy procedures and catheters. MATERIALS AND METHODS: Between July 8, 1999, and August 4, 2000, 80 percutaneous gastrostomy catheters were placed in 80 patients in 80 attempts. Twenty-five 16-, 18-, or 20-French balloon-retained catheters and 55 20-French mushroom-retained catheters were inserted. Typically, the type of catheters placed was based on operator preference. However, balloon-retained tubes were preferred for use in patients with obstructive head and neck or esophageal malignancies, and mushroom-retained catheters were preferred for use in demented or combative patients. Follow-up was conducted through chart reviews and telephone interviews. The technical success, procedural complications, and catheter complications were recorded. Chi-square statistical analysis was performed. RESULTS: Technical success was 100% (80/80 patients), and no procedural complications occurred. In patients who received balloon-retained catheters, the major complication rate was 0%, the minor complication rate was 8% (2/25 patients), and the tube complication rate was 68% (17/25 patients). The following complications occurred: catheter dislodgment (n = 17), superficial cellulitis (n = 1), and bleeding gastric ulcer (n = 1). In patients who received mushroom-retained catheters, the major complication rate was 0%, the minor complication rate was 3.6% (2/55 patients), and the tube complication rate was 3.6% (2/55 patients). The following complications occurred: superficial cellulitis (n = 2), tube occlusion (n = 1), and peristomal tube leakage (n = 1). No significant differences in major or minor complications were found between the gastrostomy procedures. Balloon-retained catheters had a significantly higher rate of tube complications (p < 0.001). CONCLUSION: Compared with balloon-retained catheters, mushroom-retained gastrostomy catheters are significantly more durable, more secure, and less prone to tube dysfunction. Mushroom-retained catheters should be the preferred type of gastrostomy catheter to place in patients whenever possible.

Metallic stents deployed in synthetic arteriovenous hemodialysis grafts.

OBJECTIVE: The purpose of our study was to review the success of metallic stent treatment of intragraft stenoses in patients with synthetic arteriovenous hemodialysis grafts. MATERIALS AND METHODS: Between May 1993 and May 1997, 19 metallic stents were placed in 11 patients (seven women, four men; age range, 41-83 years) to treat elastic intragraft stenoses or graft dissections. Before stent placement, all patients had experienced multiple episodes of graft thrombosis, had very limited vascular access for hemodialysis, and were considered poor surgical candidates. RESULTS: The technical success rate was 100%, and there were no procedural complications. Using life-table analysis, we found primary patency to be 36% at 6 months after stent placement, 12% at 12 months, and 12% at 18 months. Secondary patency was 91% at 6 months after stent placement, 71% at 12 months, and 47% at 18 months. The mean and median patencies per intervention were 4.2 and 3.6 months, respectively. Mean and median secondary graft patencies were both 14 months (range, 3 days-32 months). Puncture through the stents occurred during dialysis, causing stent distortion and fracture. Eight stents had a linear fracture suggesting compression contributed to the stent distortion. No clinically evident complications related to stent placement occurred. CONCLUSION: Metallic stent deployment can salvage access in synthetic arteriovenous grafts by alleviating intragraft stenoses. Patency of intragraft stents is similar to venous stents used to treat other hemodialysis-related stenoses; however, fracture of Wall-stents occurs with prolonged graft use, especially in areas of needle punctures.

Sonographic needle guidance in cholangiography in children.

PURPOSE: To evaluate feasibility and benefits of sonographic guidance of percutaneous transhepatic cholangiography (PTC) in children with liver transplants. MATERIALS AND METHODS: The authors prospectively followed 24 PTC procedures in 19 pediatric patients (11 females, 8 males; age 3 months to 17 years) randomized to fluoroscopic or sonographic guidance. The number of needle passes, the contrast material dose, fluoroscopy time, and procedure time for each procedure were recorded. All patients were transplant recipients-six whole and 13 reduced-size grafts. Cases were randomly assigned to two groups: group I, fluoroscopically guided PTC (12 procedures); group II, sonographically guided PTC (12 procedures). RESULTS: The technical success rate was 92% (11 of 12) for each group. In group I, there were two procedure-related complications: postprocedural fever caused by biliary to portal vein fistula, and peritoneal bleeding requiring surgery. In group II, there were no procedure-related complications. A mean of 8.2 +/- 3.7 needle passes were required in group I compared to only 2.0 +/- 1.3 in group II (P < .0001). A mean contrast material dose of 19.5 mL +/- 13.4 was required in group I compared to only 2.5 mL +/- 1.9 in group II (P < .001). A mean procedure time of 15.7 minutes +/- 7.4 was required in group I compared to only 6.1 minutes +/- 4.5 in group II (P < .001). A mean fluoroscopy time of 10.4 minutes +/- 5.0 was required in group I compared to only 1.0 minutes +/- 0.7 in group II (P < .0001). CONCLUSION: In pediatric patients who have undergone liver transplantation, sonographic guidance significantly decreases the number of needle passes, contrast material dose, and fluoroscopy time required for PTC.

Radiologic placement of implantable chest ports in pediatric patients.

OBJECTIVE: We evaluated the technical success and complications associated with radiologic placement of implantable chest ports in children for long-term central venous access. MATERIALS AND METHODS: Between May 1, 1996 and January 11, 2000, 29 chest ports were placed in 28 children (15 girls, 13 boys; age range, 2-17 years; mean, 11.7 years). The patient's right internal jugular vein was used for access in 93% (27/29) of the procedures, and a collateral neck vein was used as a conduit to recanalize the central veins in two procedures because of bilateral jugular and subclavian vein occlusion. All procedures were performed in interventional radiology suites. Both real-time sonography and fluoroscopy were used to guide venipuncture and port insertion. Follow-up data were obtained through the clinical examination and electronic review of charts. RESULTS: Technical success was 100%. Fourteen percent of the catheters were removed prematurely, including one catheter removed 17 days after placement because the patient's blood cultures were positive for Candida albicans. No patients experienced hematoma, symptomatic air embolism, symptomatic central venous thrombosis, catheter malposition, or pneumothorax. The median number of days for catheter use by patients was 280 days (total, 9043 days; range, 17-869 days). The rate of confirmed catheter-related infection was 14% or 0.04 per 100 venous access days. One catheter occluded after 132 days. CONCLUSION: In pediatric patients, radiologists can insert implantable chest ports using real-time sonographic and fluoroscopic guidance with high rates of technical success and low rates of complication.

Radiologic placement of tunneled hemodialysis catheters in occluded neck, chest, or small thyrocervical collateral veins in central venous occlusion.

PURPOSE: To evaluate interventional radiologic placement of tunneled hemodialysis catheters in small thyrocervical collateral veins or in occluded veins in the neck or chest in patients with limited venous access. MATERIALS AND METHODS: A femoral venous approach was used to recanalize occluded veins or catheterize small collateral veins in 24 patients in whom all major central veins were occluded. A loop snare or catheter was used as a target for antegrade puncture. Metallic stents were deployed if necessary. Once antegrade access was secured, catheters were placed in a conventional fashion. RESULTS: Technical success was achieved in 22 (88%) of 25 procedures (one patient underwent two procedures). All catheters functioned immediately after placement. There were two procedural complications: a vasovagal episode requiring intravenously administered atropine sulfate and an episode of respiratory distress requiring intubation. There were no instances of pneumothorax, nerve injury, or bleeding complications. Catheter malfunction requiring exchange occurred at a rate of 0.67 per 100 catheter days. Infection requiring catheter removal occurred at a rate of 0.06 per 100 catheter days. Primary patency was 90% at 1 month, 71% at 6 months, and 25% at 12 months. Secondary patency was 100% at 6 months and 70% at 12 months. CONCLUSION: In patients undergoing hemodialysis in whom conventional venous access sites have been exhausted, interventional radiologic venous recanalization for the placement of permanent catheters is safe and effective. Catheters placed in recanalized veins or small collateral veins have shorter primary patency rates compared with those of conventionally placed catheters, but the former can be maintained for relatively long periods.

Percutaneous transhepatic cholangiography and biliary drainage in pediatric liver transplant patients.

OBJECTIVE: In children with liver transplants, percutaneous transhepatic cholangiography has a critical role in evaluation and treatment of biliary complications. The purpose of this study was to evaluate the technical success and complication rates of percutaneous transhepatic cholangiography and biliary drain placement in children who underwent liver transplantation. MATERIALS AND METHODS: Between January 1, 1995 and July 1, 1999, 120 pediatric percutaneous transhepatic cholangiography procedures were performed in 76 patients (34 boys, 42 girls; age range, 5 months to 18 years; mean age, 5.3 years). Patients had received left lateral segment, whole-liver, or split-liver transplant grafts. Retrospective review of all pertinent radiology studies and electronic chart review were performed. RESULTS: A diagnostic cholangiogram was obtained in 96% (115/120) of all procedures and drainage catheter placement was successful in 89% (88/99) of attempts. In patients with nondilated intrahepatic bile ducts, a diagnostic cholangiogram was obtained in 92% (46/50) of procedures, and drainage catheter placement was successful in 76% (19/25) of attempts. Minor complications occurred in 10.8% (13/120) of procedures and included transient hemobilia with mild drop in hematocrit level (n = 2), mild pancreatitis (n = 1), fever with bacteremia (n = 5), and fever with negative blood cultures (n = 5). Major complications occurred in 1.7% (2/120) of procedures and included sepsis (n = 1) and hemoperitoneum requiring immediate surgery (n = 1). CONCLUSION: Percutaneous transhepatic cholangiography and biliary drainage can be performed with high technical success and low complication rates in pediatric liver transplant patients, even in those with nondilated intrahepatic ducts.

Conventional and hydrocolonic US of the appendix with CT correlation performed by on-call radiology residents.

RATIONALE AND OBJECTIVES: The purpose of this study was to assess the feasibility and accuracy of emergent hydrocolonic ultrasonography (US) performed by on-call residents in patients suspected of having appendicitis. MATERIALS AND METHODS: Thirty-one patients with a clinically equivocal diagnosis of appendicitis were prospectively evaluated with conventional US, hydrocolonic US, and appendiceal computed tomography (CT). Midlevel radiology residents performed the US examinations while they were on call. Sensitivity, specificity, and accuracy for diagnosing appendicitis were calculated for conventional and hydrocolonic US by using clinical outcome as the standard. Results of US and CT of the appendix were also correlated. Residents recorded their diagnostic confidence for conventional and hydrocolonic US. All patients were able to hold the rectally administered contrast material until completion of both hydrocolonic US and appendiceal CT. RESULTS: The sensitivity for detecting appendicitis with conventional US, hydrocolonic US, and appendiceal CT was 50%, 75%, and 100%, respectively. Specificity was 96%, 93%, and 93%, respectively. Identification of the normal and abnormal appendix improved from 13% (four of 31 patients) with conventional US to 35% (11 of 31 patients) with hydrocolonic US. The radiology residents' diagnostic confidence increased from 0.74 with conventional US to 0.83 with hydrocolonic US. CONCLUSION: Hydrocolonic US is a feasible addition to conventional US examination for patients suspected of having appendicitis. It improves sensitivity, increases radiology residents' confidence, and is well tolerated by patients.

Radiologic gastrostomy placement: pigtail- versus mushroom-retained catheters.

OBJECTIVE: Two different types of percutaneous fluoroscopic gastrostomy procedures were prospectively evaluated. SUBJECTS AND METHODS: Between January 1, 1998, and August 10, 1999, 127 percutaneous gastrostomy catheters were placed in 128 patients in 128 attempts. Seventy-five 12- or 14-French pigtail-retained catheters and fifty-two 20-French mushroom-retained catheters were inserted. Catheters were generally placed on the basis of operator preference except pigtail-retained tubes were preferentially placed in patients with head and neck or esophageal malignancies and mushroom-retained catheters were preferentially placed in neurologically compromised or combative patients. The technical success, procedural complications, and catheter complications were recorded. Statistical analysis was performed. RESULTS: Ninety-nine percent (127/128) of the procedures were successful, and there were no procedural complications. One catheter was not placed because the colon intervened between the abdominal wall and stomach. In patients who received pigtail-retained catheters, the major complication rate was 3% (2/75), the minor complication rate was 8% (6/75), and the tube complication rate was 36% (27/75). The following complications were seen: tube occlusion (n = 12), inadvertent catheter removal (n = 8), peristomal tube leakage (n = 7), superficial cellulitis (n = 4), aspiration pneumonia (n = 2), and T-fastener cellulitis (n = 2). In patients who received mushroom-retained catheters, the major complication rate was 0%, the minor complication rate was 2% (1/52), and the tube complication rate was 2% (1/52). Complications were superficial cellulitis (n = 1) and partial catheter fracture (n = 1). There were no significant differences in major and minor complications between procedures. Pigtail-retained catheters had a significantly higher rate of tube complications (p < 0.001) CONCLUSION: Compared with pigtail-retained catheters, mushroom-retained gastrostomy catheters are more durable and secure and are less prone to tube dysfunction. These catheters should be preferentially placed when possible.