Constantin Cope

Magnetic Resonance Imaging of Angiographically Occult Runoff Vessels in Peripheral Arterial Occlusive Disease

BACKGROUND Bypass grafting to arteries of the lower leg has become standard surgical management of advanced peripheral vascular disease. Its success depends on identifying suitable distal vessels. Preoperative preparation includes imaging of the arteries of the lower leg, usually by conventional contrast arteriography. An alternative procedure, magnetic resonance (MR) angiography, has been successfully employed in patients with various cardiovascular diseases, but its possible value in patients with peripheral vascular disease has received little attention. METHODS We used both conventional and MR angiography in preoperative studies of the lower-leg vessels of 23 patients (25 legs) with peripheral arteriosclerosis and arterial insufficiency, and developed independent therapeutic plans based on the information provided by each technique. When the plans differed, the interventional procedure judged more likely to save the limb was performed. The findings of conventional and MR angiography were verified by intraoperative arteriography, postinterventional arteriography, or direct operative exploration. RESULTS MR angiography detected all vessels identified by conventional angiography, whereas conventional arteriography failed to detect 22 percent of the runoff vessels identified by MR angiography. The detection by MR angiography of vessels not identified by conventional angiography altered the surgical management of the disorders of four patients (17 percent) and guided successful bypass procedures. CONCLUSIONS MR angiography is a noninvasive technique with greater sensitivity than conventional contrast arteriography for detecting distal runoff vessels in patients with peripheral arterial occlusive disease.

Magnetic resonance venography for the detection of deep venous thrombosis: Comparison with contrast venography and duplex Doppler ultrasonography

PURPOSE Contrast venography is the gold standard for diagnosis in deep venous thrombosis (DVT); however, this technique is invasive and requires the use of potentially hazardous contrast agents. Although duplex Doppler ultrasonography is accurate in the evaluation of lower extremity DVT, it is less accurate in the assessment of the pelvic and intraabdominal veins. Magnetic resonance venography (MRV) has recently been developed, and our purpose was to determine whether MRV could accurately demonstrated DVT when compared with duplex scanning and contrast venography. METHODS Eighty-five patients underwent contrast venography and MRV from the inferior vena cava to the popliteal veins to rule out DVT. Thirty-three of these patients also underwent duplex scanning. Blinded readings of these studies were compared for the presence or absence and extent of venous thrombosis. RESULTS DVT was documented by contrast venography in 27 (27%) venous systems. Results of MRV and contrast venography were identical in 98 (97%) of 101 venous systems, whereas results of duplex scanning and contrast venography were identical in 40 (98%) of 41 venous systems. All DVTs identified by contrast venography were detected by MRV and duplex scanning. The discrepancies were due to false-positive MRV (3) and duplex scanning (1) results. When compared with contrast venography, MRV had a sensitivity of 100%, specificity of 96%, positive predictive value of 90%, and negative predictive value of 100%. For duplex scanning the sensitivity was 100%, specificity was 96%, positive predictive value was 94%, and negative predictive value was 100%. CONCLUSIONS It is concluded that MRV is an accurate noninvasive venographic technique for the detection of DVT.

Endovascular management of splenic artery aneurysms and pseudoaneurysms

Splenic artery aneurysms and pseudoaneurysms are being diagnosed with increasing frequency by modern imaging. The question of appropriate treatment—surgical or endovascular—arises more often. We review our experience and that of others as documented in the literature. The information available suggests that endovascular management of a splenic artery aneurysm or pseudoaneurysm offers a lower complication rate than surgery, but postprocedure imaging to ensure obliteration is recommended.

Upper gastrointestinal hemorrhage and transcatheter embolotherapy: clinical and technical factors impacting success and survival.

PURPOSE To identify clinical and technical factors influencing the outcome of transcatheter embolotherapy for nonvariceal upper gastrointestinal (GI) hemorrhage and to quantify the impact of successful intervention on patient survival. MATERIALS AND METHODS A retrospective review was performed of all patients (n = 163) who underwent arterial embolization for acute upper GI hemorrhage at a university hospital over an 11.5-year period. Clinical success was defined as target area devascularization that resulted in the clinical cessation of bleeding and stabilization of hemoglobin level. The clinical condition of each patient at intervention was defined by history, laboratory examination, and two composite indicator variables. With use of logistic regression, the dependent variable, clinical success, was modeled on two categories of clinical and technical variables. A final model regressed patient survival on clinical success and other clinical variables. RESULTS None of the procedural variables analyzed had a significant influence on clinical success. Several clinical variables did impact clinical success, including multiorgan system failure (OR, 0.36; P =.030), coagulopathy (OR, 0.36; P =.026), and bleeding subsequent to trauma (OR, 7.1; P =.040) or invasive procedures (OR, 6.5; P =.009). Regardless of their clinical condition at intervention, patients who underwent clinically successful embolization were 13.3 times more likely to survive than those who had an unsuccessful procedure (CI, 4.54-39.2; P =.000). Nevertheless, patients with multiorgan system failure were 17.5 times more likely to die, independent of the outcome of the procedure (CI, 0.014-0.229; P =.000). CONCLUSION Arresting nonvariceal upper GI hemorrhage with transcatheter embolotherapy has a large positive effect on patient survival, independent of clinical condition or demonstrable extravasation at intervention. Aggressive treatment with transcatheter embolotherapy is advisable in patients with acute nonvariceal upper GI hemorrhage.

Management of Unremitting Chylothorax by Percutaneous Embolization and Blockage of Retroperitoneal Lymphatic Vessels in 42 Patients

PURPOSE To demonstrate the applicability, technique, and efficacy of percutaneous transabdominal catheter embolization or needle disruption of retroperitoneal lymphatic vessels in the treatment of high-output or unremitting chylothorax. MATERIALS AND METHODS Forty-two patients (21 men, 21 women; mean age, 56 y; range, 19-80 y) who had chylothorax with various etiologies were referred from the thoracic surgery department for treatment as soon as chylothorax was documented. The thoracic duct was punctured and catheterized via a peritoneal cannula to facilitate embolization with use of microcoils, particles, or glue; if there were no lymph trunks that could be catheterized, attempts were made to disrupt lymph collaterals with use of needles. RESULTS The thoracic duct was catheterized in 29 patients and embolized in 26 patients. In patients with lymph trunks that could be catheterized, treatment resulted in cure within 7 days in 16 patients and partial response with cure within 3 weeks in six patients. In the patients with lymph trunks that could not be catheterized (n = 16), disruption with use of needles resulted in cure in five patients and partial response in two patients. Cure and partial response rates after thoracic duct embolization and needle disruption were 73.8%, with no morbidity. Surgical thoracic duct ligation was performed in seven patients. The nonprocedural mortality rate was 19%. Follow-up was 3 months or longer. CONCLUSIONS Effective percutaneous treatment of high-output or medically uncontrollable chylothorax was performed promptly and safely in more than 70% of referred cases. This procedure should be attempted, especially if patients are very ill, before riskier surgical thoracic duct ligation is considered.

Magnetic resonance angiography of peripheral runoff vessels

Recent improvements in magnetic resonance imaging techniques have made magnetic resonance angiography (MRA) a very useful adjunct to invasive angiography. Fifty-five limbs in 51 patients with occlusive peripheral vascular disease were studied with both MRA and contrast arteriography. The magnetic resonance and contrast arteriograms were read by radiologists and surgeons and separate interventional plans were based on each study. The MRA findings differed significantly from those of conventional arteriography in 26 limbs (48%). In every case MRA visualized all of the same vessels and hemodynamic stenoses seen on the contrast arteriogram. In 48% of the cases, however, MRA revealed additional findings. Thus the discrepancies in the two studies were always the result of the failure of the arteriogram to reveal all of the patent vessels seen on MRA. The additional information provided by MRA resulted in alteration of the interventional plan in 11 cases (22%). In nine cases (18%) target vessels suitable for use in a limb-salvage procedure were identified by MRA, although they had been missed by conventional arteriography. In all of these cases, intraoperative arteriograms confirmed the suitability of these vessels for use in technically successful bypass procedures. In two cases (4%) additional information provided by MRA identified a target runoff vessel for bypass grafting that proved to be a better alternative than the one that would have been chosen on the basis of contrast arteriography.(ABSTRACT TRUNCATED AT 250 WORDS)

Management of Chylothorax by Percutaneous Catheterization and Embolization of the Thoracic Duct: Prospective Trial

PURPOSE To prospectively assess the efficacy of percutaneous transabdominal thoracic duct catheterization and embolization in the management of patients with high-output chylothoracic effusions. MATERIALS AND METHODS Eleven consecutive patients (four women and seven men; mean age, 53 years) were referred with chylothorax secondary to esophagectomy (n = 4), lobectomy (n = 1), lung transplant (n = 1), coronary artery bypass (n = 1), aortic graft (n = 2), lymphangioleiomyomatosis (n = 1), and gunshot wound (n = 1). Two patients were brought by ambulance and referred back to their hospital on the same day. Pedal lymphography was used to opacify the cisterna chyli or major retroperitoneal lymphatic trunks. When patent, these were punctured under local anesthesia with a fine needle and the thoracic duct was catheterized over a microguide wire with use of a 3-F catheter; the duct was embolized with platinum coils. Patients were followed up for decrease in thoracic drainage output and morbidity. RESULTS There were no retroperitoneal ducts suitable for catheterization in six patients because of previous abdominal surgery, trauma, or lymphangioleiomyomatosis; the thoracic duct was successfully catheterized in five patients, a 45% technical success rate. Thoracic duct embolization was performed in four patients, with cure of effusion in two. In the other two patients, one with lymphangioleiomyomatosis and the other with nonchylous pleural fluid, continued effusion was successfully treated by means of pleurodesis. Of two patients with previous thoracic duct ligation, one was found to have the duct incompletely tied. The authors were surprised to find that previous major abdominal surgery, chronic aortic dissection, and lymphangioleiomyomatosis could obliterate major retroperitoneal lymphatic ducts and the cisterna chyli. Percutaneous study of the thoracic duct with aqueous contrast medium was more sensitive than lymphography with iodinated oil. There was no morbidity. CONCLUSIONS Catheterization of the thoracic duct was possible in all patients who had patent major retroperitoneal lymphatic trunks. Thoracic duct embolization was curative in patients with demonstrable duct leakage. Previous abdominal surgery, aortic dissection, and lymphangioleiomyomatosis can lead to silent occlusion of retroperitoneal lymphatic trunks. Percutaneous thoracic duct catheterization and embolization is safe and can replace surgical ligation in some patients.

Diagnosis and Treatment of Postoperative Chyle Leakage via Percutaneous Transabdominal Catheterization of the Cisterna Chyli: A Preliminary Study

PURPOSE To assess the feasibility of percutaneous transabdominal puncture and catheterization of the cisterna chyli or lymphatic ducts (PTCLD) in patients with postoperative chyloperitoneum and chylothorax, and to identify and possibly embolize the chylous fistula. MATERIALS AND METHODS Five patients had postoperative uncontrolled chyle fistulas. Two patients with chylothorax had thoracic duct (TD) ligation after esophagectomy and neck surgery. The other three patients had chylous ascites after surgery of the pancreas, the aorta, and the esophagus, respectively. After lymphographic opacification, the cisterna chyli (CC) or retroperitoneal lymph ducts were punctured transabdominally with a 21-gauge needle and catheterized with a 3-F catheter to reach the TD if possible. Microcoils were used to embolize a TD laceration. RESULTS Lymph ducts as small as 2-3 mm were catheterized successfully in three patients. The TD was catheterized in two patients; one TD fistula was embolized with cure of chylothorax. In one patient with a surgically tied TD, duct occlusion was confirmed despite continued pleural effusion. Three fistulas, not seen with lymphography, were identified in two of three chylous ascites and one chylothorax. There was no morbidity. As a result of this procedure, four of five patients did not require repeated operation. CONCLUSIONS PTCLD in the study of chyle fistulas was feasible and safe in the management of five patients and clinically useful in four patients; transabdominal catheter lymphography with aqueous contrast medium is more sensitive than pedal lymphography. Further evaluation is necessary.

Chemoembolization of Hepatocellular Carcinoma with Cisplatin, Doxorubicin, Mitomycin-C, Ethiodol, and Polyvinyl Alcohol: Prospective Evaluation of Response and Survival in a U.S. Population☆

PURPOSE To evaluate response and survival after hepatic chemoembolization with cisplatin, doxorubicin, mitomycin-C, Ethiodol, and polyvinyl alcohol in a U.S. population of patients with hepatocellular carcinoma. MATERIALS AND METHODS Thirty-eight consecutive patients were treated: 35% stage I, 62% stage II, 3% stage III. Fifty-one percent had cirrhosis. Chemoembolization was performed at approximately monthly intervals for one to seven sessions (mean, 2.2). Pretreatment and posttreatment cross-sectional imaging and alpha-fetoprotein (AFP) levels were obtained prospectively 1 month after treatment and then every 3 months. Thirty-day response was calculated by means of the the World Health Organization/Eastern Cooperative Oncology Group criteria. RESULTS One patient was lost to follow-up. In seven patients, lesions became resectable after chemoembolization. Among 13 evaluable patients with initially elevated AFP level, 70% had a partial biologic response (>50% decrease in AFP), 15% had a minor response (25-50% decrease), and the remaining 15% remained stable. Among 25 patients evaluable for morphologic response, 36% had a partial response, 32% had a minor response, and 32% remained stable. No patients had progression of disease while receiving therapy. The cumulative survival was 60% at 1 year, 41% at 2 years, and 16% at 3 years. Two patients developed progressive hepatic failure. Thirty-day mortality was 3% (one patient). CONCLUSION These results compare favorably to published response and survival data for chemoembolization of advanced hepatocellular carcinoma from Asia and Europe.

Translumbar Embolization of Type 2 Endoleaks after Endovascular Repair of Abdominal Aortic Aneurysms

ENDOVASCULAR repair of abdominal aortic aneurysms is a rapidly proliferating technique. Unlike conventional “open” aneurysm repairs, patients may develop immediate or delayed “endoleaks” requiring remediation either by catheter-based or surgical intervention. Endoleaks are classified into one of four categories (1,2). A leak at an attachment site (proximal, middle, or distal) is classified as type 1. In collateral endoleaks (type 2), blood travels from a branch vessel in the nonstented portion of the aorta or iliac arteries. Blood flow then takes a circuitous route, emptying into the aneurysm sac via retrograde flow through a lumbar artery, inferior mesenteric artery, or other vessel originating from the aneurysm. This type of leak is the most common and is unrelated to the type or configuration of stent-graft used. Endoleaks that are a result of a defect in, or failure of, the graft material are defined as type 3, whereas those resulting from stent-graft wall porosity are called type 4. Most controversial is the fate of branch vessel (type 2) endoleaks, usually arising from inferior mesenteric artery or lumbar artery retrograde flow into the excluded abdominal aortic aneurysm sac. While some of these leaks have been demonstrated to thrombose with the passage of time, distressing reports of continued abdominal aortic aneurysm enlargement from untreated branch endoleaks are accumulating (3–5). One of the barriers to catheterbased remediation of type 2 endoleaks has been access to the offending vessel supplying the excluded abdominal aortic aneurysm sac. Access to the inferior mesenteric artery can be gained by catheterization of the superior mesenteric artery and selecting the inferior mesenteric artery through collaterals. This approach is tedious, time-consuming, and not always successful, particularly if there is an incomplete arc connecting the SMA-IMA axis (6– 10). Patent lumbar arteries are even less easily accessed. Translumbar access to the abdominal aorta was first introduced more than 70 years ago (11,12). Modifications made this technique of clinical value in the 1960s (13). Even though the long history and safety of this procedure is well documented, at the present time, translumbar angiography is usually reserved for patients with poor peripheral vascular access. The purpose of our investigation was to access the feasibility of direct aneurysm sac puncture and endoleak embolization via a translumbar approach. MATERIALS AND METHODS