Cardiovasc Intervent Radiol (1996) 19:215–221

CardioVascular and Interventional Radiology q Springer-Verlag New York Inc. 1996

CIRSE ‘95 Summary Report Proceedings of the Annual CIRSE Meeting and Postgraduate Course Lyon, September 10–14, 1995 Robert F. Dondelinger, Lie`ge, Belgium Program Committee Chairman During the Annual Meeting of the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) in Lyon, September 10–14, 1995, 361 abstracts were submitted, of which 17% concerned vascular imaging, mainly duplex Doppler and MRI, and 7%–9% were devoted to each of the following topics: vascular malformations, vascular stents, embolization techniques, percutaneous transluminal angioplasty (PTA) and transjugular intrahepatic portosystemic shunt (TIPS). Overall, retrospective clinical studies and feasibility papers accounted for 87% of the presentations. Two percent of the papers presented were multicenter, prospective, or randomized studies, and 2% were devoted to new interventional devices. In the following summaries, the main highlights of the meeting are analyzed. The abstract numbers refer to CVIR, vol. 18, supplement 1, 1995.

Vascular Malformations Jean-Jacques Merland (Paris, France) The International Society for the Study of Vascular Anomalies (ISSVA) was founded in 1992 after an 18year period of biennial workshops. The pre-classification system used at the ISSVA clearly separates hemangiomas from vascular malformations, as they are entirely different lesions. The combined special session CIRSE-ISSVA dealt with their appearances and current management. Enjolras (Abstract 19) described their characteristics. Hemangiomas are benign tumors. They grow in infancy and regress through childhood. When investigations are necessary to confirm their diagnosis or delineate their extent, ultrasonography (US), computed tomography (CT), Doppler and magnetic resonance imaging (MRI) are the most useful techniques. Pharmacologic treatments are indicated in some alarming hemangiomas. Vascular malformations consist of dysplastic vessels [capillary (CM), venous (VM), lymphangitic (LM)] and they never regress. They are either slow-flow (CM, VM, LM) or fast-flow [arterial malformations (AM), arteriovenous malformations (AVM)] and complex combined types exist

that are either systematized (the so-called Klippel– Trenaunay, Parkes–Weber, Cobb, Sturge–Weber and Wyburn–Mason syndromes) or disseminated (Osler– Weber–Rendu disease, Bean or BRBN syndrome). Noninvasive imaging techniques (US, CCD, CT, MRI, MR angiography) are in the front line for visualizing these lesions. Angiography has a limited role in the diagnosis, although it remains a standard tool for AVMs. Wassef (Abstract 20) described the histopathologic aspects of the two main categories: hemangiomas are highly cellular lesions, whereas malformations are comprised of dysplastic channels with a predominant type (histologically there are capillary, venous, capillary-venous, nodular cavernous, lymphatic, and arteriovenous malformations). Coagulation abnormalities can be associated with venous and venous-lymphatic malformations: the hemostatic profile shows plasmatic coagulation activation and consumption (Abstract 21). Molecular genetics have begun to impact on the field of vascular anomalies, as shown by Boon and Mulliken (Abstract 22): mapping a familial form to a specific chromosome and finding the mutant gene will provide insight into the pathogenesis of the sporadic forms of vascular anomalies. Burrows (Abstract 37) described the MRI features of obstructive intracranial arterial anomalies, symptomatic in infants

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with extensive cervicofacial hemangiomas. These newly recognized anomalies remain unexplained, the hypothesis being either that they result from a growth factor produced by the tumor acting on the arterial walls, or that they are a consequence of the pharmacologic treatment of the hemangioma. Boukobza (Abstract 38) scored the occurrence of asymptomatic intracranial venous anomalies in a series of 40 patients with extensive head-and-neck venous malformations, and found that they were 100 times more frequent in these patients than in the population at large. Port-wine stains are best treated today using pulsed dye lasers (Abstract 23). VMs have esthetic, functional, and psychosocial consequences (Abstract 24). MRI is the gold standard for their diagnosis. Combined treatments aim at lessening the handicap: percutaneous embolization and surgical excisions are performed and many procedures are necessary over the years to maintain or obtain facial symmetry, and to control swelling and pain. Yakes (Abstract 35) stressed the fact that US, CT and Doppler, also extensively described by Guibaud (Abstract 34), and MRI (Abstract 36), are exquisite modalities to evaluate and follow VMs. Lymphatic malformations (LM) of the macrocystic type can benefit from direct puncture and intralesional sclerotherapy (Abstract 25); after an inflammatory flare-up, regression of the LM is obtained in about 60% of the cases. Surgical excision is considered when treatment fails. Surgical treatment of head-and-neck vascular malformations requires an interdisciplinary approach: therapeutic options depend on the type and evolution of the lesion (Abstract 29). Indications for surgical excision or repair can be either esthetic or functional or, rarely in AVMs, life-saving. Clinical staging of AVMs facilitates therapeutic considerations in this particularly worrisome and dangerous group (Abstract 26). Selective arterial embolization of AVMs can be a palliative treatment of complications such as hemorrhage and ulceration, or be the only treatment or the first step in surgical treatment, allowing complete resection of the lesion followed by reconstruction (Abstract 27). Surgical treatment of vascular malformations of the limbs differs according to the type and extent of the anomaly (Abstract 30). Excision of a venous lesion is always possible (step-by-step, tangential, or radical resection), except when it has infiltrated deep structures; therefore, a benefit–risk balance must be considered to avoid iatrogenic sequelae. A direct arteriovenous fistula can be resected, but AVMs are difficult to treat in limbs. Hemodynamic consequences of a vascular anomaly can sometimes be reduced using skeletonization of some marginal embryonic veins, to allow normal hypoplastic veins to recover normal function. Berlien (Abstract 28) described his original experience with the Nd:YAG laser, either with surface ice cooling, or with interstitial use, for VMs, LMs, and some growing hemangiomas.

Yakes (Abstract 40) presented his experience with ethanol embolization of VMs: ethanol offers a level of performance rarely achieved with other embolic agents in slow-flow anomalies. Yakes also presented his extensive experience with ethanol embolization of highflow AVMs. Burrows (Abstract 41) described an interesting technique for intravascular treatment of large VMs, using platinum fiber coils before sclerotherapy with 100% ethanol, in order to slow the flow and prevent the embolic agent from migrating. Other presentations discussed the treatment of AVMs by an endovascular approach and surgery. As vascular malformations are rare diseases, diagnostic and therapeutic strategies require an interdisciplinary approach. Multidisciplinary study groups for vascular anomalies represent a decisive step in patient care and research.

Arterial Interventions: Angioplasty and Related Techniques Dierk Vorwerk (Aachen, Germany) Forty-seven papers and nine posters were submitted dealing with angioplasty and related techniques. They were presented during the work-in-progress session as well as in four special sessions dedicated to the subject. Most of the papers covered clinical data on angioplasty; only seven presentations dealt with experimental work, mainly focused on neointimal hyperplasia and intraindividual comparisons of different types of stents and of angioplasty versus stent placement (Abstracts 159, 161, 194). The largest number of papers was dedicated to the use of covered stents in aortic aneurysms or in other locations. There were also several papers on clinical follow-up data of different non-covered stents in various locations (Abstracts 123, 155, 157). Thus, stent techniques accounted for the largest proportion of angioplasty presentations. Follow-up results of the new low-profile Memotherm nitinol stent were presented (Abstract 122) and showed similar follow-up results compared with other types of stents such as the Strecker stent (Abstract 123), with excellent outcome especially in iliac implants. A single paper (Abstract 120) reported the results of percutaneous bifurcational reconstruction using a kissing stent technique in a larger series. Although described as a feasible technique for that location, primary patency as low as 51% after 2 years was disappointing compared with the patency of iliac stents in general and raises several questions: whether this technique is really a practical alternative to surgery and what mechanisms contribute to decreased patency. Treatment of abdominal aortic aneurysm by the use of stented grafts (Chuter device, EVT prosthesis) or grafted stents (Stentor device) or co-knitted prostheses (nitinol stents with woven Dacron) was the hot topic of

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this year (Abstracts 9–13, 118, 121). Most authors reported on small series, but there was one extended series on use of the Stentor device (Abstract 12). Postimplantation syndrome with this or other devices was not discussed in depth. Postimplantation leakage is a problem that occurs frequently, but the appropriate approach is still under discussion. All the devices used are still being investigated, but there is a general impression that grafted stents work better than stented grafts. Use of covered stents in the iliac axis was reported by several groups on the basis of small series. Some iliac aneurysms and some iliac stenoses or occlusions were treated (Abstracts 149, 150, 153, 241). Apart from treatment of aneurysms, where noncovered stents are not an alternative, it is as yet undetermined whether covered stents really do offer an advantage, since follow-up results in the iliac arteries are favorable for conventional stents and restenosis seems possible in covered stents also. An interesting paper (Abstract 156) compared the technical results of primary iliac stenting versus percutaneous transluminal angioplasty (PTA) and selective stenting and showed a similar technical outcome with regard to pressure gradients. These findings may serve as an important argument in the discussion on whether primary stenting should be done in all iliac lesions. There were few papers on renal PTA, all discussing follow-up results of renal PTA or stenting. For peripheral angioplasty, one paper discussed the infrapopliteal use of a subintimal recanalization technique; this had a fair technical success and a good limb-salvage rate in a series of patients with critical limb ischemia (Abstract 244). In conclusion, arterial interventions were dominated by stent technique, with description of more consolidated follow-up data for conventional stents and new work with covered devices. It is important to mention that alternative recanalization techniques such as lasers or atherectomy played no role this year, while balloon angioplasty proved still to be an evergreen.

Venous Interventions: Angioplasty and Related Techniques Christoph Zollikofer (Winterthur, Switzerland) The scientific session on Venous Interventions included 14 papers (Abstracts 162–168 and 170–175). Two papers (Abstracts 162, 174) dealt with the treatment of superior vena cava (SVC) syndrome: one with the Palmaz stent in 11 patients and the other using Wallstents for the brachiocephalic veins and Gianturco–Ro¨sch stents for the SVC in a total of 23 patients. Technical success rate was 100%, with improvement of symptoms in all patients in both series. There seems no difference in long-term results between

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the different stents. One paper demonstrated the usefulness of primary stenting of benign lesions of the venous system, such as in catheter-associated thrombotic obstruction of the brachiocephalic veins, SVC and inferior vena cava (IVC) obstruction, and hepatic vein stenosis in Budd–Chiari syndrome (BCS) (Abstract 163). A high technical success rate of 86% was paralleled with good clinical success (95.5%) and primary and secondary patency rates in the order of 78% and 91% respectively. Two papers (Abstracts 166, 167) dealt with interventional procedures of BCS in large vessel disease, secondary to congenital webs, occlusion of hepatic veins, external compression, or postsurgical stenosis (orthotopic liver transplantation). While PTA alone of congenital webs generally had good long-term results, other stenoses and especially extrinsic compression of the hepatic veins and intrahepatic portion of the IVC required stenting. A further percutaneous treatment of BCS by the use of transjugular intrahepatic portosystemic shunt (TIPS) was presented, with good results in patients with portal hypertension due to small and large hepatic vein obstruction and centrolobular liver congestion and necrosis (Abstract 165). In many cases percutaneous interventions served to bridge the time until liver transplantation was possible. Catheterdirected thrombolysis for iliofemoral venous thrombosis seems highly successful (90%) for acute thrombosis (Abstract 168) lasting less than 1 week, and is successful in about 80% of cases for 2- to 3-weekold occlusions with a low rate of complications: two suspected pulmonary embolisms without sequelae, and three hematomas in 64 limbs. In view of the low probability of significant pulmonary embolism in the authors’ experience, prophylactic filter placement in the IVC seems not to be warranted. About one third of the patients had underlying malignancies and in 63% and 46% PTA or stenting respectively was performed as an additional treatment. Thrombotic occlusion more than 4 weeks old had significantly lower success rates (25%). Endovascular stenting as an alternative to surgical treatment for patients with a pelvic vein spur (May–Thurner syndrome) was presented by two groups (Abstracts 170, 173); they achieved excellent initial results and a 90% patency rate at 1 year followup. In view of the difficult surgery and often unsatisfactory long-term results of extra-anatomical sapheno-saphenous bypasses (Palma), stent placement seems the method of choice in this disease affecting mostly younger and female patients. Percutaneous intervention for idiopathic subclavian vein occlusion using low-dose thrombolysis followed by PTA and/or stent placement had an 88% technical success rate and primary patency rate of 62% up to 2 years follow-up (Abstract 172). Successful treatment of two cases of hemodialysis shunt pseudoaneurysms by ultrasoundguided compression, a technique successfully applied

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following femoral artery puncture, was also presented (Abstract 172). Occlusion of the spermatic vein for symptomatic varicoceles using a microcatheter technique and microcoils was technically successful, with absence of flow on postembolization Doppler examination in 92% of 65 patients. Improvement of function tests and/or doubling of the sperm counts was achieved in 71%; the rate of recurrence was only 3%. The authors justified the significantly higher costs (compared with sclerosing therapy) by the low recurrence rate and absence of significant complications (Abstract 175).

Chemoembolization and Embolization in General Mario Bezzi (Rome, Italy) Lencioni reported on a prospective randomized study comparing chemoembolization with a combination of chemoembolization and percutaneous ethanol injection (PEI) in the treatment of hepatocellular carcinoma (HCC) larger than 3 cm in size (Abstract 134). The therapeutic response, as assessed by imaging, was significantly better in the latter group. The 3-year survival, although higher in the latter group, was not significantly different (72% vs 43%; p ú 0.05). A multiinstitutional study reported by Mathieu compared chemoembolization with no treatment in 96 patients with HCC (Abstract 135). The treated patients underwent four chemoembolizations, one every 2 months, with embolization of the whole liver. The 3-year and 4-year survival rates were similar in the two groups, being 28% and 13%, respectively, in the treated group and 14% and 12% in the untreated group (p Å 0.13). A drawback of the study was that only 11% of the more than 800 patients enrolled in the study could be randomized, and that superselective embolization was not performed. Prognostic factors for patients undergoing PEI were analyzed in one study (Abstract 138). PEI was best indicated in patients with uninodular HCC, smaller than 3 cm in size, alpha-fetoprotein levels below 200 ng/ml, and good liver function. Another study tested the locoregional antitumoral effect of Mitoxantrone in experimental liver tumors (Abstract 137). Tumor growth was inhibited by intratumoral injection of Mitoxantrone more than by intraarterial administration of the same drug or intratumoral injection of ethanol. Two papers warned against possible complications after chemoembolization for neuroendocrine and carcinoid tumors of the liver. Liver abscess developed in four patients with metastases from neuroendocrine neoplasm; interestingly, three of them had a biliary-enteric anastomosis. All required surgical drainage of the abscess (Abstract 140). Arterial complications, such as spasm, dissection, and obstruction, were frequently encountered in patients with carcinoid tumors and caused

difficulties in performing the chemoembolization. Carcinoid reactions were also common in patients with a frank carcinoid syndrome. These complications were more common during the first procedure than during repeated treatments (Abstract 141). Bilbao reported their experience in 43 patients with locally advanced lung carcinoma treated by intravenous and intraarterial chemotherapy (Abstract 145). In patients with stage IIIA tumors, partial response was obtained in 70% of cases, with a median survival of 19 months and a 3year actuarial survival of 33%. Results were not as favorable in patients with stage IIIB tumors. Goffette reported his 7-year experience with embolization in upper gastrointestinal bleeding (Abstract 271). In a group of 70 patients, embolization was performed in 87% of cases, and provided definitive cure in 80% of patients. Interestingly, in 33% of cases the embolization was performed without angiographic evidence of bleeding, following the information provided by endoscopy. A serious potential complication of Swan–Ganz catheters is formation of pulmonary artery pseudoaneurysms. In a 4-year period, Thony reported 5 patients with such a complication, all presenting with hemoptysis within 3 weeks after surgery (Abstract 270). All were diagnosed by angiography and successfully treated by embolization with coils. Embolization of pelvic varices with Histoacryl was performed by Capasso in 15 women with pelvic pain and dyspareunia. Immediate variceal occlusion was obtained in all cases, with only minor complications. Symptomatic relief was obtained in 67% of patients and complete relief in 40%; in 33% of cases (5 patients) the treatment was not effective, but in 3 of 5 it was concluded that pelvic varices were not the cause of the symptoms. Interestingly, the possibility of a pregnancy was not negatively affected by the procedure (Abstract 277).

Transjugular Intrahepatic Portosystemic Shunt (TIPS) Henri Rousseau (Toulouse, France) The session on TIPS covered various aspects, and some papers dealt with new indications as well as with longterm results. Three papers concerning the results of TIPS for refractory ascites were presented. The authors concluded that this technique dramatically improved the clinical condition of patients with cirrhosis, and helped in controlling ascites resistant to medical treatment. However, Rose (Abstract 72) demonstrated that no response was observed in 32% of cases when patients had severe impairment of liver or renal function. Bilbao (Abstract 74) reviewed the records of 17 patients treated for refractory ascites and found that ascites was mild or absent in 56%, 66% and 57%

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respectively at 1, 6 and 12 months. A significant improvement in renal sodium excretion was demonstrated. Bezzi (Abstract 69) presented the preliminary results of a randomized controlled trial comparing TIPS and sclerotherapy in the prevention of variceal bleeding in 61 patients. The authors concluded that the rebleeding rate tends to be lower in the group treated with TIPS (13% vs 25%) but the mortality rate was greater (13% vs 6%). However, the difference was not statistically significant. Goffette (Abstracts 67, 68) presented two papers related to rare indications for TIPS. They demonstrated that TIPS may be a valuable procedure in some uncommon clinical settings due to portal hypertension, such as hepato-renal and hepato-pulmonary syndrome, prior to abdominal surgery in cirrhotic patients and those with acute Budd–Chiari syndrome. The second paper dealt with the usefulness of embolization of large varices with blood flow steal phenomenon, to treat TIPS insufficiency or thrombosis. Abbott (Abstract 52) discussed the cause and prognostic factors of early mortality after TIPS placement. In their series of 45 patients of various Child’s class determinations, 10 died within 30 days. They found that liver failure in Child’s class C was a major contributor to death. They also noted that patients undergoing TIPS procedures were at higher risk for renal failure and adult respiratory distress syndrome if they had pulmonary edema at the time of shunt placement or if they were receiving vasopressin. Denys (Abstract 64) and Foshager (Abstract 65) presented their experience with the prevalence and management of stenosis after TIPS placement. They reviewed the records of 38 and 68 patients respectively and confirmed previously reported results concerning shunt obstruction. These complications appear frequently (65%), with a mean time to presentation of 3 months following TIPS placement, and are related to stenosis of the hepatic vein in most cases. A decrease in the baseline mid-shunt velocity seems to be the most sensitive Doppler sign of TIPS stenosis. Two papers described new experimental TIPS techniques: Otal (Abstract 6) tested covered stents in pigs to prevent restenosis after TIPS insertion, but found that Dacron covering does not prevent pseudo-intima formation over the stent. Dondelinger (Abstract 8) conducted an interesting study evaluating the possibility of establishing a direct portocaval shunt with a stent graft in the pig, by an exclusive percutaneous approach. Percutaneous Thrombectomy and Local Thrombolysis Frank Boudghene (Paris, France) Thrombectomy The results obtained with the Hydrolyser catheter (7 Fr) are variable depending on the vessel treated (Ab-

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stracts 97, 98). Recanalization of occlusion was obtained within 5 min in 80% of cases; best results were obtained on hemodialysis fistulae (92%). Other mechanical systems can also clear artificial grafts with similar success rates. However, a complementary treatment was mandatory in most cases: PTA in 84% of cases to treat an underlying stenosis, and thromboaspiration in 60% of cases as an adjunct to thrombolysis. The technique was more efficient on fresh thrombus (õ 2 weeks), less efficient on native arteries or in cases of chronic thrombosis. Distal migration was noted in 14%–21% of the cases in iliac arteries; dissection and hemolysis occurred in 4% of cases. A complementary thrombolysis was necessary in 16%–25% of the cases. When using the Amplatz Thrombolyser (8 Fr) in association with a fibrinolytic infusion, fragments less than 13 mm in diameter were obtained in less than 6 min (Abstract 94). Dissolution of 90% of the clot was obtained in veins, but stent implantation was required to treat residual thrombi. No hemolysis or pulmonary emboli were reported. A new thrombectomy catheter (8 Fr) using the Venturi effect was presented (Abstract 99). Seventy-six percent of thrombi were cleared after a 5-min procedure. A complementary treatment was necessary with this device, including PTA, thromboaspiration or chemical thrombolysis. Thrombolysis Four papers were presented (Abstracts 93, 96, 101, 102) on slow perfusion of Urokinase through a 5 Fr catheter during 24 hr in acute arterial ischemia of the lower limbs with a low complication rate (7%). Urokinase was particularly efficient in emboli (66%) but less effective in thrombosis (35%) or in elderly patients (32%). Recanalization was obtained in 89% of cases (82% at the popliteal level) but only 28%–40% remained patent at 3 years, and best results were observed in males and in chronic bypass grafts. This procedure seems interesting, if the underlying cause can be treated (46%–59% PTAs). Most of the failures were due to chronic lesions and a poor run-off (9%). Accelerated thrombolysis (õ 3 hr) was obtained in 81 cases by pump injection of rt-PA through the pulse-spray catheter (Abstract 100). A PTA completed the treatment in half the cases, but hemorrhagic complications occurred in half the cases. A 91% recanalization rate was obtained in less than 1 hr, using a low dose of urokinase (õ 200,000 IU) infused rapidly using a microporous balloon that was regularly advanced (Abstract 95). PTA was done in 48% and thromboaspiration in 35% of cases. There was a 15% embolization rate during the procedure, and 4% of other drawbacks. The 6-month patency was 62%–87% with this simplified technique, which reduces both the amount of drug injected and the duration of administration.

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Genitourinary Tract and Gynecological Interventions Frank Boudghene (Paris, France) Genitourinary Tract Treatment of delayed urinary tract injuries occurring during a war was emphasized in one report (Abstract 203). Treatment of benign ureteral stenoses with dilatation and stenting was analyzed. Long-term follow-up is necessary, as late recurrences remain possible despite stenting. Chronic and long segmental post-anastomotic stenoses have a particularly poor prognosis (Abstract 204). Extensive experience concerning treatment of complications in transplanted kidneys was reported, and showed that despite dilatation and stenting, surgery remained necessary in one third of cases (Abstract 205). A new technique for percutaneous nephrostomy was reported, but seems difficult to perform in cases with a hypogastric scar due to previous abdominal surgery (Abstract 206). Prostatic cryosurgery under 3D guidance was discussed. Infection and obstruction are among the most common complications reported. The incidence of impotence resulting from this procedure has not been determined (Abstracts 207, 208). One paper described color Doppler imaging in cases of impotence (Abstract 209) and confirmed that it lacks sensitivity compared with cavernography. The examination was normal in 46% of patients, although one third had a venous leak. Among the patients in whom the Doppler examination was abnormal (54%), 23% had a low peak systolic velocity and 31% a high enddiastolic velocity. In fact, concerning venous leaks in these cases there were 30% false negatives (low systolic peaks with venous leakage) and 10% false positives (high diastolic velocity without venous leakage). This method seems interesting as a screening modality, but cannot separate arteriogenic from combined causes of impotence. Embolization efficiently cured priapism due to a post-traumatic arterio-cavernous fistula in a young patient (Abstract 284).

papers on three topics—long-term results for metal stents in benign strictures, new stent designs, and endobiliary ultrasound—will be reviewed. One paper (Abstract 104) dealt with balloon dilatation of benign biliary strictures. There were 16 patients (10 bilio-enteric anastomoses, 6 primary strictures). After a mean follow-up of 5 years, 3 patients (19%) had a recurrence of the stricture after 12, 17 and 52 months, respectively. Two papers (Abstracts 105, 106) reported on stent placement in benign biliary obstructions (21 and 16 patients respectively). Both papers reported a mean follow-up of 3 years (10–60 months vs 20–54 months). A recurrent obstruction was observed in 4 of 21 patients (19%) versus 4 of 16 patients (25%). Reobstruction was observed 2–31 months (mean 15 months) after stent placement. Two papers (Abstracts 114, 115) reported on new stent designs for treatment of patients with malignant biliary obstruction. In the first (Abstract 114), misplacement occurred in 2 of 17 patients because the stent position could not be corrected during placement. Minimal shortening and good expansive force were advocated as improvements by the authors. In the second (Abstract 115), data were presented of a pilot study in 20 patients treated with a Wallstent covered by an elastic polyurethane membrane. Total covering resulted in distal migration in 115 patients; partial covering, leaving the proximal and distal ends uncovered, produced stent stability in 15 of 15 patients. After a follow-up of 1–8 months reobstruction due to sludge (n Å 4) and tumor overgrowth (n Å 2) was observed. Two papers dealt with endoluminal ultrasound of the biliary tract. In one (Abstract 197) a 30 MHz US transducer was used in 22 patients. Endoluminal ultrasound was useful in T-staging, demonstrating tumor infiltration into the lumen, the wall of the common bile duct, and adjacent structures. In 75% of patients the sonographic findings were confirmed at subsequent surgery. The other paper dealt with lymph-node staging using a 12.5 MHz transducer (Abstract 199). The results were compared with histopathologic data and CT findings. The accuracy of endoluminal US for diagnosing regional lymph node metastases was 83% (CT 28%; p õ 0.5).

Gynecological Interventions The occurrence of pregnancy in patients previously embolized for hemorrhage from gestational trophoblastic tumor was reported (Abstract 276). In another paper, efficient treatment of intrauterine synechiae was reported with the use of an angioplasty balloon on an outpatient basis (Abstract 290). Biliary Interventions Johannes Lammer (Vienna, Austria) A wide variety of papers were presented during three sessions on biliary interventional procedures. Different

Biopsy and Fluid Drainage Various topics on biopsy and fluid drainage were presented during two sessions. Giron (Abstract 210) reported on a combined fluoroscopic and CT-guided thoracic biopsy technique. Among the 110 cases analyzed, the pneumothorax rate was 15% and the overall accuracy of the biopsies was 85%–90%. Almeida (Abstract 211) reviewed 392 lung biopsies: pneumothorax was observed in 11.8%, hemorrhage in 4.8%; sufficient material was obtained by cutting needles in 96.5%. In one paper (Abstract 236) percutaneous cholecystos-

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tomy (PC) procedures were reviewed retrospectively in 61 patients: patients with typical symptoms of cholecystitis responded in 81% of cases to PC. In oligosymptomatic patients only imaging findings such as pericholecystic fluid and multiple imaging abnormalities correlated with a positive response to PC. Among 33 patients with acute pancreatitis treated exclusively by percutaneous drainage, a mean drainage time of 85 days resulted in a 90% success rate; however, 3 patients died acutely from septic shock (n Å 2) or bleeding (Abstract 237). Abstract 239 analyzed diverticular abscess drainage in 45 patients. The procedure was successful in 34 of 45 patients (84%). After a mean drainage time of 9 days 33 patients underwent one-stage colon resection; 5 patients did not need surgery at all. Thus preoperative drainage avoids a two-stage operation and colostomy. In Abstract 240, 52 transgluteal pelvic drainage procedures were reviewed. Forty-six of the 52 patients (88%) were treated successfully after a mean drainage period of 8 days. Causes of failure were multilocular collections or Crohn disease. Displacement of the catheter occurred in 4 patients, and temporary leg pain was observed in 2. Thus a transgluteal access route remains effective for pelvic fluid collections.

Imaging Techniques Session Willem Mali (Utrecht, The Netherlands) In this session the main focus was on conventional angiography and ultrasound duplex studies. Conventional angiography The bolus chase technique was presented (Abstract 84). With this digital technique a contrast bolus given through an intraarterial catheter is chased from the abdomen to the toe. By obtaining a mask in advance a subtraction can be made. A good correlation with standard digital subtraction angiography techniques was found. Two papers addressed the problem of the optimal puncture site and advocated the radial (Abstract 90) or the transbrachial approach (Abstract 91), both with minimal complications, good technical results, and apparent advantage for the patients. Two other papers addressed the topic of radiation dose during interventional procedures. On the basis of the doses obtained during interventions a physician can perform at least 700 PTAs a year before he reaches the radiation limit (Abstract 88). The other group showed that a prototype X-ray shield for use in neuroradiological interventions was so effective that it removed 90% of the radiation, making it possible to work without a lead apron (Abstract 89). Contamination of catheters and the assess-

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ment of International Organization for Standardization (ISO) standards was the subject of another study (Abstract 87). In general the amount of contamination was below the level required for parenteral injections. Flushing the catheter with saline is an effective cleaning method. Pressure measurements in pulmonary angiography for lung emboli before or during and after contrast injection were the subjects of one presentation (Abstract 86). It was shown that there is very little effect of an injection on the pressure and that the contrast seems to be extremely safe. Ultrasound Duplex studies were another important topic. The relatively cheap noninvasive and powerful vascular technology seems to be extremely well suited to serve as an initial screening method. Its cost effectiveness in the assessment of renal artery stenosis was the subject of one study (Abstract 80). Flow velocity with turbulence and assessment of the tardus/parvus waveform were the main criteria for the presence or absence of disease in a group of 90 patients. Technical failure of ultrasound was noted in 25% of cases. In 70%, accessory vessels were missed. Yet there is a high negative predictive value, making ultrasound an acceptable screening method. In the last three years many articles have addressed the problem of translating the angiographic criteria for significant carotid stenosis of the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and European Carotid Surgery Trial (ECST) studies into duplex criteria. One study showed that a peak systolic velocity ú 200 cm/sec is most consistently in agreement with an angiographic stenosis of ú 70% (Abstract 82). These are values also found in other studies. Duplex can also be used to assess the thoracic venous inflow (Abstract 83) and vertebral arteries (Abstract 85) in a reasonably reliable way, although in the former study a considerable number of false positives was present and in the latter a high number of false negatives. Another application of duplex is to see whether it can predict clinical outcome. Duplex after PTA of iliac artery stenosis can be used to predict technical outcome, not clinical outcome (Abstract 81). Electron Beam CT There was one presentation concerning the initial results of electron beam CT (EBCT) in cardiac imaging. This technology, which has existed for many years but has had a limited dissemination, is now rapidly becoming popular, especially for intracardiac and coronary imaging. This study (Abstract 79) showed that EBCT provides important information in patients suspected of having intracardiac masses.

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