Thrombocytopenia in Patients with Gastric Varices and the Effect of Balloon-occluded Retrograde Transvenous Obliteration on the Platelet Count.

OBJECTIVES: Gastric varices primarily occur in cirrhotic patients with portal hypertension and splenomegaly and thus are probably associated with thrombocytopenia. However, the prevalence and severity of thrombocytopenia are unknown in this clinical setting. Moreover, one-third of patients after balloon-occluded retrograde transvenous obliteration (BRTO) have aggravated splenomegaly, which potentially may cause worsening thrombocytopenia. The aim of the study is to determine the prevalence and degree of thrombocytopenia in patients with gastric varices associated with gastrorenal shunts undergoing BRTO, to determine the prognostic factors of survival after BRTO (platelet count included), and to assess the effect of BRTO on platelet count over a 1-year period. MATERIALS AND METHODS: This is a retrospective review of 35 patients who underwent BRTO (March 2008-August 2011). Pre- and post-BRTO platelet counts were noted. Potential predictors of bleeding and survival (age, gender, liver disease etiology, platelet count, model for end stage liver disease [MELD]-score, presence of ascites or hepatocellular carcinoma) were analyzed (multivariate analysis). A total of 91% (n = 32/35) of patients had thrombocytopenia (<150,000 platelet/cm(3)) pre-BRTO. Platelet counts at within 48-h, within 2 weeks and at 30-60 days intervals (up to 6 months) after BRTO were compared with the baseline pre-BRTO values. RESULTS: 35 Patients with adequate platelet follow-up were found. A total of 92% and 17% of patients had a platelet count of <150,000/cm(3) and <50,000/cm(3), respectively. There was a trend for transient worsening of thrombocytopenia immediately (<48 h) after BRTO, however, this was not statistically significant. Platelet count was not a predictor of post-BRTO rebleeding or patient survival. However, MELD-score, albumin, international normalized ratio (INR), and etiology were predictors of rebleeding. CONCLUSION: Thrombocytopenia is very common (>90% of patients) in patients undergoing BRTO. However, BRTO (with occlusion of the gastrorenal shunt) has little effect on the platelet count. Long-term outcomes of BRTO for bleeding gastric varices using sodium tetradecyl sulfate in the USA are impressive with a 4-year variceal rebleed rate and transplant-free survival rate of 9% and 76%, respectively. Platelet count is not a predictor of higher rebleeding or patient survival after BRTO.

Ureteric embolization for lower urinary tract fistulae: use of two amplatzer vascular plugs and N-butyl cyanoacrylate employing the "sandwich" technique.

PURPOSE: This study describes and evaluated the effectiveness of occluding distal ureters in the clinical setting of urinary vaginal (vesicovaginal or enterovesicovaginal) fistulae utilizing a new technique which combines Amplatzer vascular plugs and N-butyl cyanoacrylate. MATERIALS: This is a retrospective study (January 2007-December 2010) of patients with urinary-vaginal fistulae undergoing distal ureter embolization utilizing an Amplatzer-N-butyl cyanoacrylate-Amplatzer sandwich technique. An 8-12-mm type-I or type-II Amplatzer vascular plug was delivered using the sheath and deployed in the ureter distal to the pelvic brim. Instillation of 0.8-1.5 cc of N-butyl cyanoacrylate into ureter proximal to the Amplatzer plug was performed. This was followed by another set of 8-12-mm type-I or type-II Amplatzer vascular plugs in a technique referred to as the "sandwich technique." RESULTS: Five ureters in three patients were occluded utilizing the above-described technique during the 4-year study period. Mean maximum size Amplatzer used per ureter was 10.8 mm (range, 8-12). One ureter required three Amplatzer plugs and the rest required two. Two patients (3 ureters) were clinically successful with complete resolution of symptoms in 36-48 h. The third patient (2 ureters) was partly successful and required a second Amplatzer-N-butyl cyanoacrylate sandwich technique embolization. The mean clinical follow-up was 11.3 months (range, 1.7-29.2). CONCLUSIONS: The Amplatzer-N-butyl cyanoacrylate-Amplatzer sandwich technique for occluding the distal ureter is safe and effective with a quick (probably due to the N-butyl cyanoacrylate) and durable (probably due to the Amplatzer plugs) clinical response.

Rheolytic Thrombectomy with or without Adjunctive Indwelling Pharmacolysis in Patients Presenting with Acute Pulmonary Embolism Presenting with Right Heart Strain and/or Pulseless Electrical Activity.

Purpose. To evaluate the safety and efficacy of the Possis rheolytic thrombectomy with or without indwelling catheter-directed pharmacolysis for the treatment of massive pulmonary embolus in patients presenting with right heart strain and/or a pulseless electrical activity (PEA). Materials and Methods. Retrospective review of patients undergoing pulmonary pharmacolysis was performed (07/2004-06/2009). Pre- and posttreatment Miller index scoring weres calculated and compared. Patients were evaluated for tPA doses, ICU stay, hospital stay, and survival by Kaplan-Meier analysis. Results. 11 patients with massive PE were found, with 10/11 presenting with a Miller score of >17 (range: 16-27, mean: 23.2). CTPA and/or echocardiographic evidence of right heart strain was found in 10/11 patients. 3 (27%) patients presented with a PEA event. Two (18%) patients had a contraindication to pharmacolysis and were treated with mechanical thrombectomy alone. The intraprocedural mortality was 9% (n = 1/11). Of the 10 patients who survived the initial treatment, 7 patients underwent standard mechanical thrombectomy initially, while 5 received power pulse spray mechanical thrombectomy. Eight of these 10 patients underwent adjunctive indwelling catheter-directed thrombolysis. The mean catheter-directed infusion duration was 18 hours (range of 12-26 hours). The average intraprocedural, infusion, and total doses of tPA were 7 mg, 19.7 mg, and 26.7 mg, respectively. There was a 91% (10/11) technical success rate. The failure was the single mortality. Average reduction in Miller score was 9.5 or 41% (P = 0.009), obstructive index of 6.4 or 47% (P = 0.03), and perfusion index of 2.7 or 28% (P = 0.05). Average ICU and hospital stay were 7.4 days (range 2-27 days) and 21.3 days (range 6-60 days), respectively. Intent to treat survival was 90% at 6, 12, and 18 months. Conclusion. Rheolytic thrombectomy with or without adjunctive catheter-directed thrombolysis provides a safe and effective method for treatment of acute PE in patients who present with right heart strain and/or a PEA event.

Endovascular therapy for patients with renal angiomyolipoma presenting with retroperitoneal haemorrhage.

We report our experience treating four patients with acutely bleeding angiomyolipoma (AML) of sizes between 4 and 12 cm who were managed with endovascular embolisation with a mean follow-up of 10 months. In our case series, we demonstrate that endovascular embolisation in the acute setting for bleeding AMLs is a viable treatment option. AML should be in the differential diagnosis of acutely bleeding renal masses, even when there is no fat assessed by computed tomography (CT) imaging in the renal mass.

Interventional endoscopic ultrasound-guided cholangiography: long-term experience of an emerging alternative to percutaneous transhepatic cholangiography.

BACKGROUND AND STUDY AIMS: Endoscopic retrograde cholangiography (ERC) with stenting is the procedure of choice for biliary decompression in patients with obstructive jaundice. In cases where biliary access cannot be achieved, interventional endoscopic ultrasound-guided cholangiography (IEUC) has become an alternative to percutaneous transhepatic cholangiography (PTC). PATIENTS AND METHODS: We report on 5 years of experience in patients who underwent IEUC after failed endoscopic retrograde cholangiopancreatography (ERCP). Endoscopic ultrasound-guided access to the targeted biliary duct was attempted with one of two approaches: transgastric-transhepatic (intrahepatic) or transenteric-transcholedochal (extrahepatic). A stent was then advanced over the wire and into the biliary tree. RESULTS: A total of 49 patients underwent IEUC: 35 had biliary obstruction due to malignancy and 14 had a benign etiology. The overall success rate of IEUC was 84% (41/49), with an overall complication rate of 16%. Of the 35 patients who underwent the intrahepatic approach, 23 had a stent placed across the major papilla, one had a stent placed intraductally in the common bile duct, and three patients underwent placement of a gastrohepatic stent. Resolution of obstruction was achieved in 29 patients, with a success rate of 83%. In all, 14 patients underwent an extrahepatic approach. In 8/14 (57%), stent placement across the major papilla was achieved. A transenteric stent was placed in four patients. Biliary decompression was achieved in 12/14 cases (86%). Based on intention-to-treat analysis, the intrahepatic approach achieved success in 29 of 40 cases (73%), and the extrahepatic approach was successful in seven of nine cases (78%). There were no procedure-related deaths. CONCLUSION: IEUC offers a feasible alternative to PTC in patients with obstructive jaundice in whom ERC has failed.

Development of anti-human leukocyte antigen class 1 antibodies following allogeneic islet cell transplantation.

Currently there is minimal concern that islet allograft failure could result from the development of anti-human leukocyte antigen (HLA) antibodies reactive to the allograft. We report here a case of islet allograft failure where the recipient developed immunoglobulin G anti-HLA class I antibodies reactive to HLA antigens present in two of the three islet cell donors. The patient had no detectable anti-HLA antibodies prior to the transplant but these antibodies were detected approximately 4 months posttransplant. Of concern, these antibodies developed despite induction with anti-IL2R antibodies (Zenapex) prior to intraportal islet cell infusion, low-dose tacrolimus (12-hour troughs 3 to 5 ng/mL) and rapammune (target troughs 12 to 15 ng/mL). The patient was not presensitized with blood products or a previous allograft. Her husband, however, shared antigens present in one of the islet donors and the recipient could have been presensitized to her husband during her two pregnancies. This case clearly demonstrates that islet allografts can lead to development of anti-HLA antibodies, which can cause islet allograft failure, as is the case with solid organ transplants, and hence emphasizes the need to monitor for such antibodies pre- and posttransplant. Additionally it appears that currently recommended immunosuppression may not be sufficient to inhibit a humoral response to both alloantigens and autoantigens.

Primary sarcoma of the distal abdominal aorta: CT angiography findings.

Primary aortic angiosarcomas are extremely rare. Clinically and radiographically, they mimic atherosclerosis and atheroembolic disease. For a definitive diagnosis, histologic evaluation of the tumor or of peripheral emboli is required. The imaging findings are frequently nonspecific and in most published cases did not allow a definitive preoperative diagnosis. This is the first report of the computed tomographic angiographic findings of a primary intimal abdominal aortic sarcoma and a review of previously described imaging findings in these tumors.

CT findings following the cabrol composite graft procedure.

PURPOSE: Insertion of a composite graft and reimplantation of the coronary arteries through an intermediate Dacron tube (Cabrol composite graft procedure) has been used to treat ascending aortic aneurysms and dissections. The CT findings after the Cabrol composite graft procedure have not been previously described. METHOD: Retrospective review of 12 postoperative CT and CT angiography (CTA) studies both in the immediate postoperative period as well as during long-term follow-up was conducted. RESULTS: The Cabrol composite graft procedure produces typical CT findings consisting of a coronary conduit separate from the aortic graft. The presence of perigraft flow can be normal or abnormal depending on the time point of its occurrence and the extent of its hemodynamic consequences. CONCLUSION: Knowledge of the typical CT and CTA findings following a Cabrol composite graft procedure is essential for the correct interpretation of these studies.

Safety of CO(2)- and gadodiamide-enhanced angiography for the evaluation and percutaneous treatment of renal artery stenosis in patients with chronic renal insufficiency.

OBJECTIVE: The objective of our study was to evaluate the safety of CO(2) and gadodiamide angiography for diagnosing and percutaneously treating renal artery stenosis in patients with chronic renal insufficiency and presumed ischemic nephropathy. SUBJECTS AND METHODS: One hundred forty-six consecutive patients with chronic renal insufficiency (serum creatinine > 1.5 mg/dL) were examined for renal artery stenosis using CO(2) and gadodiamide as the angiographic contrast agents. If renal artery stenosis was detected, percutaneous balloon angioplasty with or without stenting was performed. In patients for whom 48-hr creatinine levels were available, we performed an analysis to determine the incidence of contrast-involved nephropathy (increase in serum creatinine of 0.5 mg/dL at 48 hr without identifiable cause). Major complications were reported up to 1 week, and mortality was reported up to 30 days after the procedure. RESULTS: Ninety-five patients had serum creatinine levels available at 48 hr. An increase in creatinine of greater than 0.5 mg/dL at 48 hr occurred in three patients (3.2%), presumably caused by CO(2), by gadodiamide, or by both. Neither diabetes nor the degree of preexisting chronic renal insufficiency was a predictor of worsening renal function 48 hr after the procedure. The volumes of CO(2) and gadodiamide used for diagnostic studies alone versus the volume used for interventional studies was not significantly different (for CO(2), p = 0.09; for gadodiamide, p = 0.30). Eleven major complications occurred in eight patients (5.5%). Two deaths (1.4%) occurred within 30 days. One death was due to cholesterol embolization and the other was not believed to be related to the procedure. CONCLUSION: Angiography and percutaneous treatment of renal artery stenosis in patients with chronic renal insufficiency and suspected ischemic nephropathy can be performed relatively safely using CO(2) and gadodiamide as angiographic contrast agents without an increased risk of complications. Contrast-induced nephropathy potentially occurred in 3.2% of patients. Neither the degree of underlying renal insufficiency nor diabetes was a risk factor for predicting a greater likelihood of renal function worsening at 48 hr of follow-up. The volumes of CO(2) and gadodiamide used in this study did not result in an increased risk of contrast-involved nephropathy.

Angiographic evaluation and treatment of transplant renal artery stenosis.

Transplant renal artery stenosis is an uncommon but important complication of renal transplantation. It is a potentially reversible cause of patient morbidity and allograft dysfunction, which can present both early and late in the post-transplant period. Although transplant renal artery stenosis can be detected using noninvasive imaging, definitive diagnosis and percutaneous treatment typically require the use of invasive angiographic techniques. In experienced hands, these studies can be performed safely, effectively and with a low risk of contrast induced nephrotoxicity when alternative contrast agents are used.

Gadolinium contrast agents: their role in vascular and nonvascular diagnostic angiography and interventions.

Gadolinium-based contrast agents can be used for diagnostic and interventional angiographic procedures to reduce contrast-related nephrotoxicity or in patients with a history of severe allergic reaction to iodine-containing contrast material. These agents are best used in conjunction with CO(2) to complete nondiagnostic CO(2) angiograms and to monitor the progress of a percutaneous intervention. However, the total volume of gadolinium that can be administered, the reduced quality of gadolinium digital subtraction angiography images, and the increased cost of the gadolinium-based agents can limit their use.

Feasibility of gadodiamide compared with dilute iodinated contrast material for imaging of the abdominal aorta and renal arteries.

PURPOSE: To determine the quality of digital abdominal angiograms obtained with use of full-strength, intra-arterial gadodiamide compared with similar volumes of half-strength iodinated contrast material for evaluating the abdominal aorta and renal vessels. MATERIALS AND METHODS: Twenty-five consecutive patients underwent digital subtraction arteriography of the abdominal aorta performed with equal volumes (32 mL) of either half-strength (300 mg/mL iodine) iodinated contrast material or full strength gadodiamide (0.11-0.25 mmol/kg) to evaluate the abdominal aorta and renal arteries. The contrast agent used was not known to the image readers. The abdominal aorta, left and right renal main renal artery, and first and second order segmental branches were graded separately as diagnostic or nondiagnostic by four angiographers. RESULTS: Images of the abdominal aorta were diagnostic 100% of the time for iodine and gadodiamide, 76% and 80% diagnostic for iodine and gadodiamide in the left main renal artery, respectively; and 100% and 80% diagnostic for iodine and gadodiamide in the right main renal artery, respectively. The first order segmental branches of the right and left renal arteries were graded diagnostic 72% and 56% of the time, respectively, for dilute iodinated contrast material, and 40% and 28% of the time, respectively, for gadodiamide. The second order segmental branches of the right and left kidney were graded diagnostic 24% of the time for iodinated contrast and 8% and 4% of the time, respectively, for gadodiamide. CONCLUSION: Full-strength, intra-arterial gadodiamide at doses smaller than 0.3 mmol/kg can produce diagnostic images of the abdominal aorta and main renal arteries. However, images of the intrarenal branches are usually not diagnostic.

Diagnosis of vascular compression at the thoracic outlet using gadolinium-enhanced high-resolution ultrafast MR angiography in abduction and adduction.

Gadolinium-enhanced magnetic resonance angiography allows rapid evaluation of the vascular structures of the thoracic outlet both in the neutral position and in abduction during one examination within FDA-approved dose limitations for contrast agents. The technique appears to be a good screening one for patients suspected of having vascular thoracic outlet syndrome.

Lower extremity arteriography with use of iodinated contrast material or gadodiamide to supplement CO2 angiography in patients with renal insufficiency.

PURPOSE: To determine if the use of nonionic contrast material, as compared to the use of gadodiamide to supplement carbon dioxide angiography in patients with peripheral vascular disease (PVD) and chronic renal insufficiency (CRI), results in significant worsening of renal function. MATERIALS AND METHODS: Lower extremity angiographic procedures (diagnostic and diagnostic/intervention) were performed in 40 patients with CRI (baseline serum creatinine [Cr] > 1.5 mg/dL) using CO2 alone or CO2 supplemented with the use of either nonionic contrast material or gadodiamide (up to 0.4 mmol/kg). Serum creatinine levels were obtained before the procedure and at 48 hours after the procedure. The peak Cr level was also determined for patients with a significant (> 0.5 mg/dL) Cr elevation. RESULTS: Forty-two lower extremity angiographic procedures (19 diagnostic and 23 diagnostic/interventions) were performed in 40 consecutive patients from August 1997 to October 1998, with a mean preprocedure Cr of 2.2 mg/dL and a mean postprocedure Cr of 2.4 mg/dL. Twenty-five of the 40 patients (63%) had diabetes mellitus. Fifteen procedures, including six interventions, were performed utilizing CO2 and nonionic contrast material in 15 patients. Six of these 15 patients (40%) demonstrated a Cr increase > 0.5 mg/dL at 48 hours. Seven procedures, including two interventions, were performed with CO2 alone in seven patients. No patients in this group demonstrated an increase in serum creatinine of greater than 0.5 mg/dL at 48 hours. Twenty procedures, including 15 interventions, were performed with CO2 and gadodiamide in 18 patients. In one of these 20 procedures (5%) there was an increase in Cr > 0.5 mg/dL at 48 hours The difference in worsening renal function for the nonionic contrast group (six of 15) compared with the CO2/gadodiamide group (one of 20) was statistically significant (P = .03). When comparing the use of CO2 and nonionic contrast material versus CO2 alone and with gadodiamide (six of 15 versus one of 27), the difference is also statistically significant (P < .01). The average volume of supplemental contrast material was similar in the nonionic contrast material and gadodiamide groups, as was the average volume of supplemental nonionic contrast material in the six patients with an increased Cr. CONCLUSION: The use of small volumes of nonionic contrast material to supplement CO2 angiography in patients with PVD and CRI can be associated with a significant increased risk of worsening renal function when compared to angiography performed with CO2 alone or CO2 and gadodiamide.

Interventional uroradiologic procedures performed using gadodiamide as an alternative to iodinated contrast material.

Three patients with either a history of severe allergic reactions to iodinated contrast or marked renal insufficiency underwent interventional uroradiologic procedures using full-strength gadodiamide (Gd) as a contrast agent in place of iodinated contrast material. The procedures were percutaneous access for nephrostolithotomy, antegrade pyelography with placement of a nephroureteral stent, and a diagnostic nephrostogram with exchange of a nephroureteral stent. Gd was visualized fluoroscopically and produced satisfactory digital radiographs without allergic reaction or worsening renal function. Gd can be useful in guiding interventional uroradiologic procedures when iodinated contrast material is contraindicated.

Perfusion of the kidney using extraslice spin tagging (EST) magnetic resonance imaging.

This study was undertaken to determine whether extraslice spin tagging (EST) perfusion-weighted magnetic resonance imaging is suitable for screening persons for renal perfusion deficits. Six normal and seven patient volunteers with suspected decreased renal perfusion due to renal vascular disease were imaged. X-ray angiograms were also obtained on all patients. The normalized EST signal intensity showed a linear correlation with respect to the percent stenosis measured from the X-ray angiograms. This demonstrates the potential utility of using EST for the evaluation of kidney perfusion, which was done without the need for exogenous MR contrast agents. EST is fast and less expensive than contrast-based methods. These features make EST a candidate for routine screening of patients for renal vascular disease and for the assessment of angiographically equivocal renal artery stenoses. J. Magn. Reson. Imaging 1999;10:886-891.