Jordan D. Rosenblum

The mesenteric circulation. Anatomy and physiology.

The purpose of this article is to review the angiographic appearance of the major visceral arteries, the more common variants, their embryologic origins, and some of the most common sources of collateral flow. A brief review of the physiology of the mesenteric circulation is also provided, including a discussion of the intrinsic and extrinsic mechanisms of splanchnic blood flow control.

Transjugular Intrahepatic Portosystemic Shunt Placement in Patients with Cirrhosis and Concomitant Portal Vein Thrombosis

PurposeTo determine the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) creation in patients with liver cirrhosis complicated by thrombosed portal vein.MethodsThis study reviewed 15 cases of TIPS creation in 15 cirrhotic patients with portal vein thrombosis at our institution over an 8-year period. There were 2 women and 13 men with a mean age of 53 years. Indications were refractory ascites, variceal hemorrhage, and refractory pleural effusion. Clinical follow-up was performed in all patients.ResultsThe technical success rate was 75% (3/4) in patients with chronic portal vein thrombosis associated with cavernomatous transformation and 91% (10/11) in patients with acute thrombosis or partial thrombosis, giving an overall success rate of 87%. Complications included postprocedural encephalopathy and localized hematoma at the access site. In patients with successful shunt placement, the total follow-up time was 223 months. The 30-day mortality rate was 13%. Two patients underwent liver transplantation at 35 days and 7 months, respectively, after TIPS insertion. One patient had an occluded shunt at 4 months with an unsuccessful revision. The remaining patients had functioning shunts at follow-up.ConclusionTIPS creation in thrombosed portal vein is possible and might be a treatment option in certain patients.

Median arcuate ligament compression syndrome in monozygotic twins

Twin 27-year-old women had symptomatic mesenteric ischemia caused by median arcuate ligament compression. Arteriography demonstrated severe celiac artery stenosis in one twin, celiac artery occlusion in the other, and proximal superior mesenteric artery narrowing with retrograde filling from a meandering mesenteric artery in both. Division of the ligament and direct celiac artery revascularization completely relieved symptoms in both patients. Median arcuate ligament compression of the celiac and superior mesenteric arteries can result in mesenteric ischemia. Documentation of this unusual syndrome in monozygotic twins suggests that the responsible anatomic relationships are congenital.

Intravascular Stents in the Management of Acute Superior Vena Cava Obstruction of Benign Etiology

The purpose of our study was to report our experience with percutaneous placement of intravascular stents to relieve venous occlusion in patients with acute superior vena cava syndrome resulting from benign etiologies. Six patients ranging in age from 39 to 66 years received thrombolysis followed by placement of stents within the superior vena cava or received stent placement alone as emergency treatment for symptoms of acute superior vena cava obstruction. Treatment was successful in all patients, with establishment of a patent lumen angiographically, and patients experienced prompt symptomatic relief. Follow-up examination at intervals of 5 months to 2 years has demonstrated no evidence of reocclusion. Three patients have subsequently had central lines placed across the stented vena cava for vascular access. Percutaneous placement of intravascular stents to treat acute occlusion offered a safe and effective method of treatment in patients with superior vena cava syndrome resulting from benign causes.

Treatment of deep cerebral venous thrombosis by local infusion of tissue plasminogen activator.

BACKGROUND Treatment of extensive intracranial venous sinus thrombosis with thrombolytic drugs is described, although the indications for and most efficacious technique for achieving thrombolysis remain uncertain. We report the successful lysis of superficial and deep venous system thrombosis by infusion of recombinant human tissue-type plasminogen activator (rt-PA) into the anterior superior sagittal sinus. CASE DESCRIPTION A 34-year-old man presented with headaches followed by decreased level of consciousness and left hemiplegia. Angiography showed thrombosis of the superior sagittal and both transverse and straight sinuses with extension into the internal cerebral veins. The superior sagittal sinus was catheterized via a transfemoral route and rt-PA, 25 mg, was infused. There was no significant change in the thrombosis. The catheter was left in place and rt-PA was infused at 1 mg/minute for 19 hours. Repeat angiography showed resolution of the thrombosis. The patient was placed on heparin and then coumadin. He recovered completely. CONCLUSIONS This report suggests that superselective infusion of thrombolytics into thrombosed intracranial venous sinuses can lyse intracranial venous sinus thrombosis. The thrombolytic agent must be infused for hours. The apparent successful lysis of clot in the deep venous system when infusion was into the superior sagittal sinus might be related to diffusion of rt-PA throughout the intracranial venous system or to improved venous outflow caused by lysis of clot in superficial dural sinuses.

Percutaneous Treatment of Venous Outflow Obstruction in Pediatric Liver Transplants

PURPOSE To evaluate the efficacy and safety of percutaneous dilation in the treatment of impaired venous outflow in pediatric patients with liver transplants. MATERIALS AND METHODS Review was undertaken of the records of 35 procedures to dilate impaired venous outflow in 16 consecutive children (aged 11 days to 17.8 years; mean, 7.2 +/- 5.8 y) after liver transplantation over a period of 8 years. Patients presented clinically with signs or symptoms of obstruction of the hepatic venous or inferior vena cava anastomosis and/or abnormal noninvasive imaging findings and were referred primarily to the interventional radiology department for treatment. None were excluded. Technical and clinical success rates were calculated. After venoplasty, patients with incomplete venographic resolution or pressure gradients exceeding 5 mm Hg were treated with stents. Seven died or required repeat transplantation during the study period for reasons unrelated to venous outflow obstruction. Patency rates were calculated for all other patients with sufficient follow-up in the pediatric hepatology clinic. RESULTS The combined technical success rate for venoplasty (12 of 16) and stent placement (three of 16) was 94% (15 of 16), and the clinical success rate was 81% (13 of 16). One minor complication occurred: a transient hypoxic episode. Primary patency rates were 72.7% (eight of 11) at 3 months, 60% (six of 10) at 6 months, 55.6% (five of nine) at 12 months, 50% (four of eight) at 18 months, and 50% (three of six) at 36 months. Primary assisted and secondary patency rates were 90.9% (10 of 11) at 3 months, 90% (nine of 10) at 6 months, 88.9% (eight of nine) at 12 months, 87.5% (seven of eight) at 18 months, and 83.3% (five of six) at 36 months. CONCLUSIONS Excellent technical and clinical success rates can be achieved with percutaneous dilation of impaired venous outflow after pediatric liver transplantation. Long-term patency may require repeated interventions.

Significant on-call misses by radiology residents interpreting computed tomographic studies: Perception versus cognition

The purpose of this study was to evaluate the etiology of significant false-negative computed tomographic (CT) interpretations by radiology residents on-call. Over a 1-year period, significant on-call false-negative CT interpretations were analyzed to determine whether errors were perceptual (i.e., the resident did not see the finding or findings) or cognitive (i.e., the resident did not recognize the implications or misinterpreted a finding or findings). Significant “misses” were defined as errors that delayed surgical treatment or misdirected management in a potentially life-threatening manner.A total of 12 significant false-negative interpretations occurred over a 1-year period. All head CT misses (extraaxial hemorrhage, pneumocephalus, contusion, subarachnoid hemorrhage due to ruptured aneurysm) were perceptual errors. Misses on thoracic, abdominal, and pelvic CT scans (2 abscesses, abdominal aortic aneurysm rupture, superior vena cava perforation due to catheter placement, ischemic bowel, liver laceration, hypoperfusion syndrome, appendicitis) were mixed (4 cognitive and 4 perceptual errors).Since the diagnostic possibilities of emergency head CT scans are limited, residents missed only subtle, perceptual manifestations and had little difficulty interpreting findings when they were correctly recognized. The gamut of diagnostic possibilities in the thorax, abdomen, and pelvis was more challenging to residents on-call; errors in both perception and interpretation arose with equal frequency, and the significant error rate was higher than that for head CT interpretation. Junior residents, who make most of the significant on-call errors, commonly feel overwhelmed in attempting to assimilate the knowledge required to take call. Prepartion needs to be extensive, yet it should be focused on areas that will engender optimal impact on after-hours performance. When preparing residents to interpret on-call CT studies, perceptual manifestations of neuroradiology should be emphasized, whereas a more comprehensive approach to thoracic, abdominal, and pelvic disorders needs to be stressed.

Use of CT for diagnosis of traumatic rupture of the thoracic aorta

CT imaging of traumatic aortic rupture has been both advocated and disparaged in the current literature as a reliable diagnostic modality. In a retrospective review of blunt chest trauma patients at our institution evaluated by both thoracic CT and arteriography, we found a 17% false negative rate and a 39% false positive rate. Although we feel CT is not sufficiently sensitive at present to evaluate traumatic rupture of the aorta directly, it is an invaluable adjunctive imaging modality for stable blunt chest trauma patients with equivocal chest radiographs or arteriograms.

Comparison of iodixanol and ioxaglate for adult aortography and renal/visceral angiography: A phase III clinical trial

RATIONALE AND OBJECTIVES We investigated whether iodixanol offers improved safety or tolerance compared with ioxaglate and evaluated whether iodixanol-enhanced radiographs are diagnostically comparable or superior to those produced with ioxaglate. Iodixanol is a new isosmotic hexa-iodinated nonionic contrast agent being evaluated for intravascular use. METHODS Fifty-four adult patients undergoing renal or visceral angiography, aortography, or both were enrolled in a prospective, randomized, double-blind, two-center study in which iodixanol and ioxaglate were compared. Subjects were monitored for adverse events, injection-associated discomfort, and changes in laboratory parameters and vital signs. Efficacy was measured by the overall quality of angiographic enhancement. RESULTS No serious adverse events occurred during this trial. Mild-to-moderate adverse events were more common in patients receiving ioxaglate (p = .041). Injection-associated pain was reported by three patients receiving ioxaglate and none receiving iodixanol (p = .093). Clinical laboratory and vital-sign data showed no differences between groups, and there was no difference in the overall quality of angiographic visualization (p = .711). CONCLUSION Iodixanol resulted in improved safety and patient tolerability while providing images of equivalent diagnostic efficacy compared with ioxaglate.

Iodixanol and ioxaglate in adult aortography and peripheral arteriography: A phase III clinical trial

RATIONALE AND OBJECTIVES This study compared the safety and efficacy of iodixanol with those of ioxaglate in adult patients undergoing aortography or peripheral arteriography. METHODS Forty-six patients were enrolled in this controlled, randomized, double-blind, two-center study. The patients were monitored for adverse events, injection-related discomfort, and trends in laboratory data or vital signs. Diagnostic efficacy was assessed by the quality of contrast enhancement. RESULTS All procedures were diagnostic, with no significant difference in quality of visualization (p = .205). No significant difference was seen in the number of patients experiencing mild or moderate adverse effects (p = .106). Patients receiving ioxaglate reported a significantly greater incidence of injection-related pain (p = .025). CONCLUSION The results of this study support the conclusion that iodixanol at 320 mg I/kg is safe and effective for adult aortography and peripheral arteriography and causes significantly less injection-related pain than ioxaglate.