Abstracts of Current Literature

Abstracts of Current Literature

VASCULAR-ARTERIAL Diagnosis

Accurate Assessment of Abdomi- nal Aortic Aneurysm with Intra- vascular Ultrasound Scanning: Validation with Computed Tomo- graphic Angiography. Jeroen A. van Essen, Elma J . Gussenhoven, Aad van der Lugt, et al. J Vasc Surg 1999; 29:631-638. (E.J.G., Erasmus University Rotterdam, Department of Echocardiology (Ee 2312), PO Box 1738, 3000 DR Rotterdam, The Neth- erlands)

Purpose: The Purpose of this study was to assess the accuracy of intravascular ultrasound ( M J S ) parameters of abdominal aortic aneurysm, used for endovascular grafting, in comparison with computed tomographic angiography (CTA). Methods: This study was designed as a descrip- tive study. Between March 1997 and March 1998, 16 patients with abdominal aortic aneurysms were studied with angiography, I W S (12.5 MHz), and CTA. The length of the aneurysm and the length and lumen diameter of the proximal and distal neck obtained with I W S were compared with the data obtained with CTA. The measurements with I W S were repeated by a second observer to assess the reproduc- ibility. Tomographic IVUS images were reconstructed into a longitudinal for- mat. Results: I W S results identified 31 of 32 renal arteries and four of five accessory renal arteries. A comparison of the length measurements of the aneurysm and the proximal and distal neck obtained with I W S and CTA revealed a correlation of 0.99 (P < .001), with a coefficient of variation of 9%. I W S results tended to underestimate the length as compared with the CTA results (0.48 ? 0.52 cm; P < .001). A comparison of the lumen diameter measurements of the proximal and distal neck derived from I W S and CTA showed a correlation of 0.93 (P < .001), with a coefficient of variation of 9%. IVUS results tended to underestimate aneurysm neck diameter as compared with CTA results (0.68 2 1.76 mrn; P = .006). Interobserver agreement of IVUS length and diameter measurements showed a good correlation (r = 1.0; P < .001), with coefficients of variation of

3% and 2%, respectively, and no significant differences (0.0 1 0.16 cm and 0.06 ? 0.36 mm, respectively). The longitudinal I W S images displayed the important vascular structures and improved the spatial insight in aneurys- mal anatomy. Conclusion: Intravascu- lar ultrasound scanning results provided accurate and reproducible measurements of abdominal aortic aneurysm. The longitudinal reconstruction of I W S images provided additional knowledge on the anatomy of the aneurysm and its proximal and distal neck. AUTHORS' ABSTRACT

MRA DIAGNOSIS

Locally Focused Contrast-En- hanced Carotid MRA. V. Yu. Ku- perman, S. K. Nagle, M. T. Alley, et al. J Magn Reson Imaging 1999; 9:663-669. (David N. Levin, Depart- ment of Radiology, MC 2026, Univer- sity of Chicago, 5841 S. Maryland Av- enue, Chicago, IL 60637)

With conventional Fourier trans- form (FT) magnetic resonance imaging (MRI), it is difficult to perform contrast-enhanced three-dimensional (3D) MR angiography (MRA) with the temporal and spatial resolution necessary to depict the carotid arteries. How- ever, locally focused (LF) MRI is a more efficient method that utilizes prior knowledge of the image content to re- construct images from sparse k-space samples. In this paper, we show how LF MRI can be used to perform high- resolution gadolinium (Gd)-enhanced 3D carotid MRA in less than 10 sec- onds. First, the accuracy of the technique was demonstrated by comparing LF and conventional (FT) images of a vascular phantom. Then the method was used to perform Gd-enhanced 3D MRA of a patient's carotid arteries. In- stead of using bolus timing, the arterial phase was retrospectively identified in a consecutive series of images, just as in X-ray angiography. AUTHORS' ABSTRACT

Surgical Renal Artery Recon- struction without Contrast Arte- riography: The Role of Clinical Profiling and Magnetic Reso- nance Angiography. Richard P.

Cambria, John L. Kaufman, David C. Brewster, et al. J Vasc Surg 1999; 29:1012-1021. (R.P.C., Massachusetts General Hospital, 15 Parkman St. WAC 458, Boston, MA 02114)

Purpose: Contrast arteriography is the accepted gold standard for diagnosis and treatment planning in patients with atherosclerotic renovascu- lar disease (RVD). In this study, the results of a selective policy of surgical renal artery reconstruction (RAR) with magnetic resonance angiography (MRA) as the sole preoperative imaging modality are reviewed. Methods: From May 1993 to May 1998, 25 patients underwent RAR after clinical evaluation, and aortictrenal MRA performed with a gadolinium-enhanced and three-dimensional phase contrast technique. Clinical presentations suggested severe RVD in all patients and included poorly controlled hypertension (16 patients), hospitalization for hypertensive crises andlor acute pul- monary edema (n = 131, and deterio- ration of renal function within 1 year of operation (n = 15). Thirteen patients had associated aortic pathologic conditions (12 aneurysms, one aor- toiliac occlusive disease), and eight of these ~ a t i e n t s also underwent non- contrast computed tomography scans. Significant renal dysfunction (serum creatinine level, 22.0 mg1dL) was present in all but four patients with 14 of 25 patients having extreme (creatinine level, 23.0 mg/dL) dysfunction. Results: Hemodynamically significant RVD in the main renal artery was verified a t operation in 37 of 38 reconstructed main renal arteries (24 of 25 patients). A single accessory renal artery was missed by MRA. RAR was comprehensive (bilateral or unilateral to a single-functioning kidney) in 21 of 25 patients and consisted of hepatorenal bypass graft (three patients), combined aortic and RAR (13 patients), isolated transaortic endar- terectomy (eight patients), and aorto- renal bypass graft (one patient). Early improvement in both hypertension control andlor renal function was noted in 21 of 25 patients without operative deaths or postoperative renal failure. Sustained favorable functional results a t follow-up, ranging from 5 months to 4 years, were noted in 19 of 25 patients. Conclusion: MRA is an adequate preoperative imaging modal-

1420 Abstracts

November-December 1999 JVIR

ity in selected patients before RAR. This strategy is best applied in cir- cumstances where the clinical presentation suggests hemodynamically significant bilateral RVD andlor in patients at substantial risk of complications from contrast angiography. AUTHORS' ABSTRACT

Magnetic Resonance Imaging of the Abdominal Aorta and Iliac Vessels using Combined 3-D Gad- olinium-enhanced MRA and Gado- linium-enhanced Fat-Suppressed Spoiled Gradient Echo Sequences. Nikolaos L. Kelekis, Richard C. Se- melka, Suvipapun Worawattanakul, et al. Magn Reson Imaging 1999; 17: 641-651. (R.C.S., Associate Professor of Radiology, Department of Radiol- ogy, CB 7510, University of North Carolina, Chapel Hill, NC 27599- 7510)

This study evaluates a combined protocol consisting of breath hold immediate post gadolinium 3-D gradient echo MR angiography and blood pool phase gadolinium-enhanced breath hold 2-D fat-suppressed spoiled gradient echo (SGE) sequences in the examination of diseases of the abdominal aorta and iliac vessels. Thirty-two patients with suspected disease of the abdominal aorta, major aortic branches, or iliac vessels underwent MR angiographic study from January 1996 to January 1997. Examinations were performed on a 1.5 T MR imager using 2-D axial SGE, coronal 3-D fast imaging in steady state precession (3-D FISP) following bolus adminis- tration of 40 mL of gadolinium, and axial and coronal blood pool phase gadolinium-enhanced fat-suppressed SGE. Post-processed data, including 3-D reconstructions using maximum intensity projection (MIP), targeted MIP, and multiplanar reconstruction (MPR) were evaluated. MR findings in all patients were correlated as fol- lows: surgery (13 patients), angiography (11 patients), contrast enhanced CT (three patients), non-contrast enhanced CT (one patient), color doppler US (two patients), and previous MR study (two patients). MR findings correlated closely with findings at surgery or other imaging studies in 31 of 32 patients. One patient had renal artery occlusion that was misinter- preted as mild stenosis. The following vascular diseases were present: aneurysm disease [lo patients: aortic aneurysm (eight patients), inflammatory aneurysm (two patients)], thoracoab- dominal aortic dissection (two pa-

tients), arteriovenous fistula (one patient), stenoses andlor occlusion of the abdominal aorta, major aortic branches and iliac vessels [12 patients: stenoses andlor occlusion of the abdominal aorta with stenoses of the iliac vessels (nine patients), renal artery stenosis (two patients), occlusion of the abdominal aorta (one patient)], and occluded artery to pancreatic transplant artery (one patient). Five patients had normal studies. The 3-D FISP technique accurately defined the luminal contours of vessels, allowing precise depiction of vessel stenosis (ie, renal artery stenosis or common iliac artery stenosis) and clear demonstra- tion of relationship of aortic branch vessels (ie, renal arteries) to underly- ing aortic pathology (ie, aortic aneurysm or dissection). Blood pool phase gadolinium-enhanced fat-suppressed SGE images were useful in the evaluation of the external surface of vessel walls, and providing accurate measurement of aneurysm diameter and other associated vascular entities (ie, inflammatory aneurysm, left-sided IVC). Targeted MIP or MPR reconstruction were important for assess- ing stenoses of medium sized vessels such as renal arteries and branches of the iliac arteries, and for identifying accessory arteries. The combination of immediate post gadolinium 3-D FISP and blood pool phase gadolinium-enhanced fat-suppressed SGE is useful in the evaluation of the abdominal aorta, major aortic branches and iliac vessels. Immediate post gadolinium 3-D FISP images provides diagnosti- cally useful information regarding vessel luminal contour, while blood pool phase gadolinium-enhanced fat- suppressed SGE provides ancillary information on the vessel wall and surrounding tissue. AUTHORS' ABSTRACT

Single-Loop Coil Concepts for In- travascular Magnetic Resonance Imaging. Harald H. Quick, Mark E. Ladd, Gesine G. Zimmermann- Paul, et al. Magn Reson Med 1999; 41:751-758. (Jorg F. Debatin, Depart- ment of Diagnostic Radiology, Univer- sity Hospital Zurich, Ramistrasse 100, CH-8091 Zurich, Switzerland)

Compared with other coil designs that have been investigated for intravascular use, the single-loop coil can be designed with a very small diameter for insertion into small vessels and with a longitudinal extent over several centimeters for multislice imaging. If it designed to be expandable

inside the target vessel, then it com- bines these features with increased signal-to-noise ratio (SNR) and pene- tration depth. Expandable single-loop coils that are capable of meeting these requirements were developed and integrated into two different com- mercial catheter-based delivery sys- tems: a self-expandable, single-loop made from NiTinol and a single-loop coil mounted on an inflatable balloon. The influence of a small-diameter co- axial cable for remote tuning and matching on the coil performance was investigated. Calculations showed the dependence of the signal on the sepa- ration between the conductors. The comparison of both catheter approaches in in vitro flow experiments and in an in vivo pig experiment revealed the influence of pulsatile flow on image quality during intravascular imaging with these designs. AUTHORS' ABSTRACT

Transesophageal Magnetic Reso- nance Imaging. Kendrick A. Shunk, Joao A.C. Lima, Alan W. Heldman, et al. Magn Reson Med 1999; 41:722-726. (Ergin Atalar, De- partment of Radiology, Johns Hopkins University School of Medicine, 601 North Caroline Street, JHOC 4241, Baltimore, MD 21287-0845)

The purpose of this study was to develop a non-invasive method of imaging the thoracic aorta that would provide both morphological detail within the aortic wall and information about regional aortic wall motion. An esophageal probe is described that allows transesophageal MR imaging (TEMRI) of the thoracic aorta and has several potential advantages over the competing non-vasculoinvasive tech- niques of transesophageal echocardi- ography (TEE) or standard MRI. The probe consists of a loopless antenna housed inside a modified Levin gas- tric tube, with external matching and tuning circuitry. Using this probe, the thoracic aorta has been imaged in longitudinal and cross-sectional views. Details of the aortic wall were readily seen. Tissue tagging for measurement of focal stresslstrain relationshius was demonstrated to be feasible. TEMRI avoids the risks inherent in intravascular MRI yet provides comparable image quality. Potential applications of the device are discussed. AUTHORS' ABSTRACT

Abstracts 1421 ~p

Volume 10 Number 10

Preservation of Renal Function by Percutaneous Transluminal Angioplasty in Ischaemic Renal Disease. Dag Paulsen, Nils-Einar Klgw, Bird Rogstad, et al. Nephrol Dial Transplant 1999; 14:1454-1461. (D.P., Lillehammer fylkessykehus, N-2600 Lillehammer, Norway)

Background: The Purpose of this study was to evaluate the effects of percutaneous transluminal renal angioplasty (PTRA) on preservation of renal function in patients with bilateral renal artery stenoses or stenosis of the artery of one functioning kidney. Methods: A total of 227 PTRAs of 223 stenoses in 135 patients were performed from 1982 to 1993 in a single centre and retrospectively reviewed. The number of PTRAs per patient was 1.7, range 1-6. Angio- graphical follow-up was performed in 77%, 120 & 82 days after the first PTRA and 273 & 345 days after the last PTRA. Follow-up of serum creatinine and blood pressure was performed in 85% after 414 ? 558 days. Long-term follow-up was performed for dialysis, surgical revascularization, renal transplantation and death, mean follow-up 8.8 years, range 5.5- 14.8. Results: The immediate techni- cal success was 90%, and another 5% were improved. The primary patency rate per patient was 43% and the secondary patency rate 64%. Improved renal function was achieved in 23% of the patients, stabilized in 56% and failed in 21%. Stabilized or improved function was higher when baseline serum creatinine was 250 pmoM (85%) than >250 pmol/l(60%). Three of 99 (3%) patients with creatinine 250 pmoM started dialysis during follow-up (41 days, 7.4 and 8 years), as did 13 of 36 (36%) patients with creatinine >250 pmol/l. Blood pressure and the number of antihypertensive drugs decreased in patients with creatinine 250 pmol/l, but was un- changed in those with creatinine >250 pmol/l. The 5-year survival rates were 84, 66 and 17% for patients with creatinine <I25 pmoM, 125-250 pmom and >250 pmol/l, respectively. Twelve patients (9%) experienced complications, including two deaths. Conclusions: Our study shows that PTRA improved or preserved the renal function in most patients with normal to moderately impaired renal function. Close follow-up and possibly

re-intervention are necessary to ob- tain satisfactory clinical and angio- graphical results. AUTHORS' ABSTRACT

I STENTS

Percutaneous Revascularization of Atherosclerotic Obstruction of Aortic Arch Vessels. Peter Hadji- petrou, Stephen Cox, Thomas Pi- emonte, et al. J A m Coll Cardiol 1999; 33:1238-1245. (Andrew Eisen- hauer, Interventional Cardiovascular Medicine, Lahey Clinic Medical Cen- ter, 41 Mall Road, Burlington, MA 01805)

Objectives: To compare stenting of aortic arch vessel obstruction with surgical therapy and to establish rec- ommendations for treatment. Back- ground: Though surgery has been considered to be the procedure of choice for subclavian and brachioce- phalic obstruction, little work has been done to compare it with stenting. Methods: Eighteen patients with symptomatic aortic arch vessel stenosis or occlusion were treated with stenting, followed by periodic clinical follow-up and noninvasive arterial Doppler studies. Data were compared with the results as shown in a sys- tematic review of a published series of surgery and stenting procedures which included comparison of techni- cal success, complications, mortality and patency. Results: Primary success in our series was 100% with improvement in mean stenosis from 84 & 11% to 1 2 5% and mean arm systolic blood pressure difference from 44 & 16 mm Hg to 3 & 3 mm Hg. There were no major complications (death, stroke, TIA, stent thrombosis or myocardial infarction). At follow-up (mean 17 months), all patients were asymp- tomatic with 100% primary patency. Literature review demonstrates equivalent patency and complications in the other published series of stenting. In contrast, there was a similar patency but overall incidence of stroke of 3 2 4% and death of 2 & 2% in the published surgical series. Con- clusions: Subclavian or brachioce- phalic artery obstruction can be effec- tively treated by primary stenting or surgery. Comparison of stenting and the surgical experience demonstrates

equal effectiveness but fewer complications and suggests that stenting should be considered as first line therapy for subclavian or brachioce- phalic obstruction. AUTHORS' ABSTRACT

ENDOVASCULAR STENT- GRAFTS

The Cost-Effectiveness of Endo- vascular Repair versus Open Sur- gical Repair of Abdominal Aortic Aneurysms: A Decision Analysis Model. Sheela T. Patel, Paul B. Haser, Harry L. Bush J r , et al. J Vasc Surg 1999; 29:958-972. ( K . Craig Kent, Chief, Division of Vascular Sur- gery, New York Presbyterian Hospi- tal, Cornell University Medical Col- lege, 525 E. 68th Street, Room F1909, New York, NY 10021)

Purpose: Endovascular repair (EVR) is a less-invasive method for the treatment of abdominal aortic aneurysms (AAAs) as compared with open surgical repair (OSR). The potential benefits of EVR include increased patient acceptance, less resource utilization, and cost savings. This study was designed to determine whether the EVR of AAAs is a cost- effective alternative to OSR. Methods: A cost-effectiveness analysis was performed using a Markov decision analysis model to compute long-term survival rates in quality-adjusted life years and lifetime costs for a hypothetical cohort of patients who underwent either OSR or EVR. Probability estimates of the different outcomes of the two alternative strategies were made on the basis of a review of the literature. The average costs of (i) the immediate hospitalization ($16,016 for OSR, $20,083 for EVR), (ii) the complications that resulted from each procedure, (iii) the subsequent interventions, and (iv) the surveillance protocol were determined on the basis of average resource utilization as re- ported in the literature and from our hospital's cost accounting system. Our measure of outcome was the cost-effectiveness ratio. Results: For our base-case analysis (70-year-old men with 5-cm a s ) , EVR was cost-effective with a cost-effectiveness ratio of $22,826-society usually is willing to pay for interventions with cost-effectiveness ratios of less than $60,000

1422 Abstracts


(eg, cost-effectiveness ratios for coro- nary artery bypass grafting and dialysis are $9500 and $54,400, respectively). This conclusion did not vary significantly with increases in proce- dural costs for EVR (ie, if the cost of the endograft increased from $8000 to $12,000, EVR remained cost-effective with a cost-effectiveness ratio of $32,881). The cost-effectiveness of EVR was critically dependent on EVR producing a large reduction in the combined mortality and long-term morbidity rate (stroke, dialysis-dependent renal failure, major amputation, myocardial infarction) as compared with OSR (ie, a reduction in the combined mortality and long-term morbidity rate of OSR from 9.1% to 4.7% made EVR no longer cost-effective). Conclusion: Despite the high cost of new technology and the need for close postoperative surveillance, EVR is a cost-effective alternative for the repair of AAAs. However, the cost-effectiveness of this new technology is critically dependent on its potential to reduce morbidity and mortality rates as compared with OSR. EVR may not be cost-effective in medical centers where OSR can be performed with low risk. AUTHORS' ABSTRACT

Should Endovascular Surgery Lower the Threshold for Repair of Abdominal Aortic Aneurysms? Samuel R.G. Finlayson, John D. Birk- meyer, Mark F. Fillinger, et al. J Vasc Surg 1999; 29:973-985. (S.R.G.F., 59 Prospect St., Sherborn, MA 01770)

Purpose: Because endovascular repair of abdominal aortic aneurysms (AAAs) is less invasive, some investi- gators have suggested that this in- creasingly popular technique should broaden the indications for elective AAA repair. The purpose of this study was to calculate quality-adjusted life expectancy rates after endovascular and open AAA repair and to estimate the optimal diameter for elective AAA repair in hypothetical cohorts of patients a t average risk and a t high risk. Methods: A Markov decision analysis model was used in this study. Assumptions were made on the basis of published reports and included the following: (i) the annual rupture rate is a continuous function of the AAA diameter (0% for <4 cm, 1% for 4.5 cm, 11% for 5.5 cm, and 26% for 6.5 cm); (ii) the operative mortality rate is 1% for endovascular

repair (excluding the risk of conversion to open repair) and 3.5% for open repair a t age 70 years; and (iii) immediate endovascular-to-open conversion risk is 5%, and late conversion rate is 1% per year. The main outcome measure in this study was the benefit of AAA repair in quality-adjusted life years (QALYs). The optimal threshold size (the AAA diameter a t which elective repair maximizes benefit) was measured in centimeters. Results: The benefit of endovascular repair is consistently greater than that of open repair, but the additional benefit is small-0.1 to 0.4 QALYs. For men in average health with gradually enlarg- ing AAAs with initial diameters of 4 cm, endovascular surgery reduces the optimal threshold diameter by very little: from 4.6 to 4.6 cm (no change) a t age 60 years, from 4.8 to 4.7 cm a t age 70 years, and from 5.1 to 4.9 cm a t age 80 years. For older men in poor health, endovascular surgery reduces the optimal threshold diameter substantially (8.1 to 5.7 cm a t age 80 years), but the benefit of repair in this population is small (0.2 QALYs). Conclusion: For most patients, the indications for AAA repair are changed very little by the introduc- tion of endovascular surgery. Only for older patients in poor health does endovascular surgery substantially lower the optimal threshold diameter for elective AAA repair. AUTHORS' ABSTRACT

rupture of a true aneurysm of the PDA. They were analyzed with regard to the mode of presentation, preoperative workup, management, and outcome. Results: All patients had severe epigastric pain from retroperitoneal hemorrhage. Computed tomography scanning and angiography were performed in all cases. Aneurysms ranged from 0.7 to 1.2 cm (median 0.9 cm). The celiac axis was stenotic or occluded in five cases. Three patients underwent emergency pancreaticoduo- denectomy. Two of them survived. In one case, section of the median arcu- ate ligament was associated with the procedure, and the patient died from an aortic dissection. Embolization was performed in the last three patients. The procedure was definitive in two cases. In one, hemorrhage recurred 8 days later and required surgical ligation of the bleeding artery. Conclu- sions: The authors recommend rapid treatment of all true aneurysms of the PDA. Because most of these aneurysms result from a stenosis of the celiac axis, selective embolization may help to preserve patency of the PDA and should, therefore, be the primary therapeutic choice in ruptured aneurysms. Close follow-up is mandatory because of possible recurrent bleeding. Appropriate and expeditious management of true PDA aneurysms should help reduce the mortality rate. AUTHORS' ABSTRACT

I EMBOLIZATION

Management of True Aneurysms of the Pancreaticoduodenal Arter- ies. Marc de Perrot, Thierry Ber- ney, Jeff Deleaval, et al. Ann Surg 1999; 229:416-420. (M.d.P., Depart- ment of Surgery, University Hospital of Geneva, rue Micheli-du-Crest 24, 1211 Geneva 14, Switzerland)

Objective: To review the authors' recent experience and that of the literature since 1973 and to provide management guidelines for true aneurysms of the pancreaticoduodenal arteries (PDA). Summary Background Data: True aneurysms of the PDA are rare, with a total of only 52 cases re- ported since 1973. Methods: Six patients were admitted to the authors' institution between 1985 and 1995 for

1 VENA CAVA FILTERS

In Vivo Evaluation of the Adjust- able Temporary Venous Spring Filter and the RF02 Temporary Filter: Comparative Study. Junro Hosaka, Sumit Roy, Knut Kvernebo, et al. Acad Radio1 1999; 6:343-351. (J.H., Department of Radi- ology, Chiba-hokusoh Hospital, Nip- pon Medical School, 1715 Kamagari, Inba-mura, Inba-gun, Chiba, 270-1694 Japan)

Rationale and Objectives: The authors performed this study to compare the in vivo efficacies of the temporary venous spring filter and the RF02 filter in an animal model. Mate- rials and Methods: Either the spring filter or the RF02 filter was placed in the inferior vena cava of 10 pigs each, and two clots (5 X 20 mm) were funneled into the filters a t 1-hour inter- vals. The second clots were funneled

Abstracts 1423

Volume 10 Number 10

without removing the first clots captured by the filters. Clot-trapping ability, caval occlusion associated with the clot-trapping procedure, arterial blood gas concentrations, and changes in arterial and iliac venous pressures were evaluated. Results: Placement of the RF02 filter caused elevation of iliac venous pressure with a maximum of 2.2 mm Hg (median) ( n = 13, P = .003). Placement of the spring filter parallel to venous flow enabled capture of 90% (nine of 10) and 100% (six of six) of the first and second clots, respectively. The RF02 filter captured clots consistently. The difference between filters was not sta- tistically significant. Both filters equally contributed to elevation of iliac venous pressure (median, 9.3 and 7.2 mm Hg [ n = 91 with the spring filter and RF02 filter, respectively). Caval occlusion occurred in 17% (one of six) and 67% (six of nine) of ani- mals after two clots were trapped in the spring filter and RF02 filter, respectively (P = .06). Other parameters were not influenced by the clot- trapping procedure. Conclusion: Al- though a larger version should be developed and better stability of the filter is needed, the spring filter proved to be an efficient filtering device and had a lower rate of caval occlusion compared with the RF02 filter. AUTHORS' ABSTRACT

DIALYSIS ACCESS

Assessment of Occlusion of the Vascular Access in Patients on Chronic Hemodialysis: Compari- son of Physical Examination with Continuous-Wave Doppler Ultra- sound. Rino Migliacci, Maria Laura Selli, Francesca Falcinelli, et al. Nephron 1999; 82:7-11. (Paolo Gresele, Institute of Internal and Vas- cular Medicine, University of Perugia, via E. dal Pozzo, 1-06126 Perugia, It- aly)

Background: Dialysis access occlusion is the most common cause of hospitalization and a frequent indi- rect cause of mortality in patients on chronic hemodialysis. The clinical assessment of an arteriovenous shunt is presently the most widely adopted method for the diagnosis of vascular access occlusion in hernodialysis patients, but no studies have yet investigated objectively its sensitivity and positive predictive value (PPV). Con-

tinuous-wave (CW) Doppler ultrasound is a simple, inexpensive, and noninvasive technique for the assessment of arterial blood flow. We have carried out a prospective evaluation of the PPV of CW Doppler for the diagnosis of vascular access occlusion in hemodialysis patients and compared it with clinical investigation. Methods: Fourty-one hernodialysis patients with clinical diagnosis of occlusion of their fistula were studied, and in 23 of them the diagnosis of occlusion was objectively validated. Results: CW Doppler in the patients in whom occlusion was objectively validated showed PPV of 86 and 83% under basal conditions and after fistula com- pression, respectively, with sensitivi- ties of 95 and loo%, respectively. Clinical diagnosis, under the same conditions, showed a PPV of 83% and a sensitivity of 100%. Conclusions: CW Doppler and clinical examination have a similar high sensitivity for the diagnosis of occlusion of the dialysis access; thus, there is no need to use routinely Doppler CW examination, unless objective documentation is required. AUTHORS' ABSTRACT

Salvage of the Nonfunctioning Ar- teriovenous Fistula. Gerald A. Beathard, Stephen M. Settle, Marty W. Shields. Am J Kidney Dis 1999; 339:910-916. (G.A.B., 3805 Green Trails South, Austin, TX 78731)

Two factors are necessary for an arteriovenous fistula (AVF) to be use- able as dialysis access. It must have adequate blood flow, and it must have a size that will allow for cannulation. An AVF can remain patent in the face of relatively low blood flow. For effective dialysis, the AVF only has to de- liver a blood flow that is marginally greater than the pump rate. Unfortu- nately, dialysis may not be technically possible in these cases with lower flow because the AVF does not ma- ture sufficiently to a size adequate for cannulation. In this prospective obser- vational series of 63 patients, failure of AVF development was the result of venous stenosis andlor the presence of accessory veins (venous side branches). The presence of these anomalies could be diagnosed by physical examination. After documentation by angiography, the patients were treated with angioplasty, venous ligation, or a combination of both. Three levels of venous ligation were performed de- pending on individual requirements: ligation of accessory veins (AVL), liga-

tion of the median cubital vein, and temporary banding of the main fistula itself. The determining factor was the appearance of the fistula after each of the procedures was accomplished relative to potential for cannulation. Of these 63 patients with nonfunctional fistulae that ranged in age from 33 to 418 days, access was salvaged in 52 patients (82.5%). This included 9 of 12 patients who required repeat procedures. The results of this study val- idate angioplasty and AVL as therapy for the salvage of AVFs that fail to develop. AUTHORS' ABSTRACT

Prognosis of Parathyroid Func- tion After Successful Percutane- ous Ethanol Injection Therapy Guided by Color Doppler Flow Mapping in Chronic Dialysis Pa- tients. Takatoshi Kakuta, Masa- fumi Fukagawa, Tomotaka Fujisaki, et al. Am J Kidney Dis 1999; 33:1091-1099. (M.F. , Division of Ne- phrology, Tokyo Teishin Hospital, 2-14-23 Fujimi, Chiyoda-ku, Tokyo 102-8798, Japan)

Selective percutaneous ethanol injection therapy (PEIT) of the parathyroid glands has been shown to be effective in chronic dialysis patients with severe secondary hyperparathyroidism. In this study, we examined whether it was possible to maintain parathyroid function within target range (intact parathyroid hormone [iPTH], 160 to 360 pgImL) in the long term after successful destruction of hyperplastic tissue. PEIT was performed in 46 patients resistant to cal- citriol pulse therapy, and all glands larger than 5 mm in diameter were destroyed by ethanol, guided by power Doppler flow mapping. Serum iPTH levels decreased from 633.3 ? 359.9 to 226.3 +- 204.7 pgImL a t 3 weeks and were maintained a t 289.9 ? 222.4 pgImL at 1 year after PEIT. To- tal alkaline phosphatase activity decreased from 384.9 ? 160.1 to 234.0 ? 110.5 IUIL a t 1 year after PEIT. In 19 patients, iPTH levels decreased into relative hypoparathyroid- ism (iPTH < 160 pg/mL) a t 3 weeks after PEIT; however, they recovered a t 1 year after PEIT (191.1 i 29.6 pgImL). Parathyroid function was maintained within target range in 80.4% of the patients a t 1 year after PEIT with appropriate medical therapy. Surgical parathyroidectomy was not required in any patient. Con- versely, in eight other patients with recurrent hyperparathyroidism after

1424 Abstracts


subtotal parathyroidectomy, iPTH levels recovered in only 50% of the patients a t l year after PEIT. Thus, destruction of hyperplastic tissue should be optimized in such patients. Recur- rent nerve palsy was observed in only one patient, but was reversible. In conclusion, selective PEIT guided by color Doppler flow mapping is an effective and safe adjunct to medical therapy with a low risk for hypopara- thyroidism. AUTHORS' ABSTRACT

The Use of a Channel-Cleaning Brush for Malfunctioning Tenck- hoff Catheters. Mick J. Kum- wenda, Frederick K. Wright. Nephrol Dial Transplant 1999; 14:1254-1257. (M.J.K., Associate Specialist, Glan Clwyd Hospital, Bodelwyddan, Clwyd LL18 5UJ, UK)

Background: Tenckhoff catheter malfunction causes morbidity in some patients on continuous ambulatory peritoneal dialysis (CAPD). Various methods of treatment of malfunction have been described; we report our experience of the use of a channel- cleaning brush for this problem. Method: Ten patients on CAPD who developed catheter malfunction were identified. The causes of malfunction were catheter migration in one patient, catheter obstruction due to fi- brin and clots in six, probable omen- tal wrapping in one, and pain on draining of PD fluid in two patients. A channel-cleaning brush was manip- ulated repeatedly in and out of the catheters using aseptic technique and fluoroscopy guidance in an attempt to restore patency or dislodge the catheter to another site. Results: CAPD was successfully re-established after this procedure in eight patients (go%), two catheters were removed from those patients in whom the use of the brush was unsuccessful. Conclusion: In this study a channel-cleaning brush was effective and safe in the treatment of Tenckhoff catheter malfunction. AUTHORS' ABSTRACT

I GASTROINTESTINAL

Variceal Ligation Compared with Endoscopic Sclerotherapy for Variceal Hemorrhage: Prospective Randomized Trial. Joaquin de la Peiia, Montserrat Rivero, Eloy Sanchez, et al. Gastrointest Endosc

1999; 49:417-423. (J.d.l.P.G., Gastro- enterology Unit, Hospital Univeris- tario "Marques de Valdecilla", Avda de Valdecilla sn, 39008 Santander, Spain)

Background: To evaluate the safety and efficiency of variceal ligation compared with endoscopic sclerotherapy, 88 patients with cirrhosis with recent variceal bleeding were randomized to undergo either treatment. Methods: Sclerotherapy was performed using ethanolamine and polidocanol injection a t 1, 2, and 3 weeks and every 3 weeks thereafter. The Stiegmann-Goff device was used for variceal ligation at the same inter- vals. Results: The rate of variceal eradication was the same for both groups, but eradication was accomplished sooner in patients undergoing variceal ligation (5.3 t 1.6 vs. 6.6 + 2.4 endoscopic sessions, P < .05) and with fewer complications (19 vs. 6, P < .005). The rate of recurrent bleeding was lower in patients treated by ligation (31% vs. 50%, P < .05). After eradication, variceal recurrence was more frequent in patients treated by variceal ligation a t 1 and 3 years (47% and 92% vs. 23% and 55%, P < .01). Portal hypertensive gastropathy was significantly worse in the patients who had variceal ligation (17 patients vs. 6, P < .01). Survival and treatment failure were similar in both groups. Conclusions: Variceal ligation was superior to sclerotherapy in terms of the rate of recurrent bleeding and the occurrence of complications but worse with respect to recurrence of varices and the evolution of portal hypertensive gastropathy. Long-term follow-up studies are required to find out whether there are deleterious effects of variceal ligation. AUTHORS' ABSTRACT

HEPATOBILIARY

Radiofrequency Ablation of Unre- sectable Primary and Metastatic Hepatic Malignancies: Results in 123 Patients. Steven A. Curley, Francesco Izzo, Paolo Delrio, et al. Ann Surg 1999; 230:l-8. (S.A.C., Dept. of Surgical Oncology, The Uni- versity of Texas M. D. Anderson Can- cer Center, 1515 Holcombe Blvd., Box 106, Houston, TX 77030)

Objective: To describe the safety and efficacy of radiofrequency ablation (RFA) to treat unresectable ma-

lignant hepatic tumors in 123 patients. Background: The majority of patients with primary or metastatic malignancies confined to the liver are not candidates for resection because of tumor size, location, or multifocal- ity or inadequate functional hepatic reserve. Local application of heat is tumoricidal; therefore, the authors investigated a novel RFA system to treat patients with unresectable hepatic cancer. Patients and Methods: Patients with hepatic malignancies were entered into a prospective, non- randomized trial. The liver tumors were treated percutaneously or during surgery under ultrasound guidance using a novel LeVeen monopolar ar- ray needle electrode and an RF 2000 generator. All patients were followed to assess complications, treatment response, and recurrence of malignant disease. Results: RFA was used to treat 169 tumors (median diameter, 3.4 cm; range, 0.5-12 cm) in 123 patients. Primary liver cancer was treated in 48 patients (39.1%), and metastatic liver tumors were treated in 75 patients (60.9%). Percutaneous and intra-operative RFA was performed in 31 patients (35.2%) and 92 patients (74.8%), respectively. There were no treatment-related deaths, and the complication rate after RFA was 2.4%. All treated tumors were completely necrotic on imaging studies after completion of RFA treat- ments. With a median follow-up of 15 months, tumor has recurred in 3 of 169 treated lesions (1.8%), but metastatic disease has developed a t other sites in 34 patients (27.6%). Conclu- sions: RFA is a safe, well-tolerated, and effective treatment to achieve tumor destruction in patients with unresectable hepatic malignancies. Be- cause patients are a t risk for the development of new metastatic disease after RFA, multimodality treatment approaches that include RFA should be investigated. AUTHORS' ABSTRACT

Hepatic Arterial Infusion Chemo- therapy using Percutaneous Cath- eter Placement with an Implant- able Port: Assessment of Factors affecting Patency of the Hepatic Artery. Hiroshi Seki, Motomasa Kimura, Norihiko Yoshimura, et al. Clin Radio1 1999; 54:221-227. (H.S., Department of Radiology, Niigata University School of Medicine, 757, 1-bancho, Asahimachi-dori, Niigata 951-8510, Japan)

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Volume 10 Number 10

Objective: To assess the factors affecting patency of the hepatic artery during hepatic arterial infusion che- motherapy (HAIC) with an implantable port system inserted percutaneously. Patients and Methods: Ninety patients with malignant hepatic tu- mours were given HAIC using percutaneous catheter placement. An end- hole catheter was inserted into the hepatic artery (conventional method) in 41 patients. An end-closed and side-hole catheter was used in 49 patients, in which the catheter tip was fixed in the gastroduodenal artery and the side hole was placed in the common hepatic artery (fixed catheter-tip method). The patency of the hepatic artery was evaluated with computed tomography (CT) arteriography using the implantable port system and angiography. Then, the factors affecting hepatic arterial patency were analysed. Results: Hepatic arterial occlusion was observed in 15 patients (17%). The overall patency of the hepatic artery was 86.9%, 78.4% and 51.5% a t 6 months, 1 year and 2 years, respectively. The patency rate of the hepatic artery was significantly higher in patients with catheter placement using fixed catheter-tip method than those using conventional method (P = .01), and in patients without transcatheter arterial chemo- embolization (TACE) prior to catheter placement than those with prior TACE (P = .01). When the variables affecting patency of the hepatic artery were studied together by multivariate analyses, the important factors were the method of catheter placement and the presence or absence of prior TACE. Conclusion: We consider that it is important for long-term patency of the hepatic artery during HAIC to use fixed catheter-tip method for percutaneous catheter placement instead of conventional method, and to select patients without prior TACE. AUTHORS' ABSTRACT

tive study of patients who underwent operative repair of laparoscopic bile duct injuries from January 1990 through December 1997. Setting: Aca- demic tertiary referral center. Main Outcome Measures: Outcome was as- sessed using a grading system based on clinical symptoms, liver function tests, and need for reintervention for anastomotic stricture. The Kaplan- Meier method was employed to estimate stricture-free survival. Results: Fifty-nine consecutive patients underwent operative repair of the following laparoscopic bile duct injuries (Stras- berg classification): B: n = 2 (3%), C: n = 1 (l%), D: n = 2 (3%), E,: n = 5 (8%), E,: n = 16 (27%), E,: n = 25 (42%), E,: n = 5 (8%), and E,: n = 3 (5%). Forty-seven patients (80%) had one or more interventions prior to the index repair. The extrahepatic left bile duct (Hepp-Couinaud approach) was used in 46 of 53 patients who underwent a Roux-en-Y hepaticojejunos- tomy. Follow-up (mean t SEM, 3.7 2 0.3 years) was complete in 54 of the 57 patients still alive. Five patients developed subsequent anastomotic strictures and were treated with percutaneous transhepatic dilation (n = 3), endoscopic dilation (n = 11, and operative revision (n = 1). Excellent to good long-term results were achieved in the remaining 49 patients (91%). Life-table analysis yielded 95% and 88% chances of stricture-free survival a t 2 and 5 years, respectively. Conclusions: Complex iatrogenic proximal bile duct injuries and strictures are amenable to operative repair using the extrahepatic left bile duct. The Hepp-Couinaud approach offers a durable result in more than 90% of patients, even after previous interventions have failed. AUTHORS' ABSTRACT

Long-term Results of Biliary Re- construction After Laparoscopic Bile Duct Injuries. Michel M. Murr, Jean-Franeois Gigot, David M. Nagorney, et al. Arch Surg 1999; 134: 604-610. (Michael B. Farnell, De- partment of Surgery, Mayo Clinic, Rochester, MN 55905)

Hypothesis: The Hepp-Couinaud approach to biliary enteric reconstruction for laparoscopic bile duct injuries provides a durable, long-term result in most patients. Design: Retrospec-

GENITOURINARY

Comparison of Bilateral versus Unilateral Varicocelectomy in Men with Palpable Bilateral Vari- coceles. Douglas Scherr, Marc Goldstein. J Urol 1999; 162:85-88. (D.S., Department of Urology, Center For Male Reproductive Medicine and Microsurgery, James Buchanan Brady Foundation, 525 E. 68th St., F9W, New York, NY 10021)

Purpose: The left varicocele is usually larger in men with bilateral varicoceles. We hypothesized that most of the benefit of varicocelectomy would derive from repair of the larger varicocele. To test this hypothesis we prospectively compared the effect of unilateral versus bilateral microsurgi- cal varicocelectomy in men with large (grade 111) or moderate (11) left varicocele associated with small but palpable (I) right varicocele. Materials and Methods: A total of 91 patients were prospectively followed and included in the study. Of the patients 65 underwent bilateral and 26 underwent unilateral left repair. All patients underwent preoperative and postoperative semen analysis. Results: Motile sperm concentration increased from 12.1 + 1.7 to 23.7 2 31.8 (95.8% change) in the bilateral group compared with an increase from 19.5 ? 21.4 to 27.8 2 34.8 (42.6% change) in the unilateral group (P < .05). Similarly, sperm concentration increased from 23.8 2 29.5 to 48.6 2 61.3 (157.6% change) in the bilateral group compared with an increase from 41.1 ? 40.9 to 59.5 ? 66.7 (44.8% change) in the unilateral group (P < .05). Conclusions: Bilat- eral varicocelectomy resulted in significantly greater improvement in post-operative seminal parameters than unilateral repair in patients with grades I1 to I11 left varicocele associated with grade I right varicocele. Even a small, unrepaired palpable right varicocele continues to have a detrimental effect on bilateral testis function. Men with bilateral palpable varicoceles require bilateral repair. AUTHORS' ABSTRACT

Do's and Don't's of Percutaneous Nephrostomy. Ronald J. Zagoria, Raymond B. Dyer. Acad Radio1 1999; 6:370-377. (R.J.Z., Department of Ra- diology, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157- 1088)

Since the development of percutaneous nephrostomy more than 40 years ago (I) , the procedure has been refined and its indications expanded. Percutaneous nephrostomy is performed to divert urine flow from the ureter, usually to bypass an obstruc-

A good, somewhat basic analysis of anatomy, technique, and complications with a good summary and a good bibliography. -Dauid Hunter, MD

1426 Abstracts


tion. It also is performed as a prelude to more complex procedures, such as endoscopy or stent placement. All of these procedures begin with a basic percutaneous nephrostomy. The technique is commonly used today, but even when performed by experienced physicians, major complications can occur in as many as 5% of patients (2-4) (Table). These major complications include sepsis, hemorrhage, and injury to an adjacent organ. To mini- mize the incidence of complications and their potential consequences, ad- herence to certain principles of percutaneous nephrostomy is advisable. AUTHORS' ABSTRACT

I NEUROINTERVENTIONAL

Embolotherapy of Aneurysms Un- der Temporary Balloon Occlusion of the Neck: In Vitro Study of a Newly Designed Eccentric Bal- loon Catheter. Thomas Schmitz- Rode, Rauf Gulcan, Markus Kilbinger, et al. Invest Radiol 1999; 34:317-321. (T.S.R., Klinik fur Radiologische Diag- nostik, Universitatsklinikum der RWTH Aachen, Pauwelsstrasse 30, D-52057 Aachen, Germany)

Rationale and Objectives: To test embolotherapy of aneurysms in an in vitro model using standard and spe- cially designed eccentric occlusion balloon catheters for simultaneous delivery of the embolization agent and occlusion of the neck of the aneurysm. Methods: Two different in vitro set- ups were used: a bifurcational aneurysm and an aneurysm with a straight parent vessel segment, both made from elastic silicone and glass. Each model was exposed to a pulsat- ing perfusion. The effluent was collected and filtered. For the bifurcational aneurysms, commercially available occlusion balloon catheters with a working channel exiting a t the tip were used. For the aneurysms with straight parent vessel, the catheters were modified so that the balloon opened eccentrically. The working channel of the catheter led to a side hole, which was located where the balloon membrane was fixed to the catheter shaft. The aneurysms were filled with coils, ethibloc, or hydrogel, and with coils combined with ethibloc or hydrogel, while the expanded balloon occluded the neck. Results: Em- bolization of aneurysms under balloon

occlusion of the neck was technically feasible with the catheter devices. Dense packing with coils was possible in all cases without coil dislocation, but unfilled interspaces remained between the coil wires. Best filling was achieved with ethibloc or hydrogel alone or in combination with coils. During the filling procedure, there was no distal embolization of the liquid agents. However, after balloon deflation, considerable amounts of hydrogel or ethibloc were washed out from the aneurysm. Conclusions: The results suggest that balloon occlusion of the neck allows compact filling and minimizes the risk of dislocation in coil embolotherapy of aneurysms. In nonbifurcational aneurysms, the eccentric balloon catheter seems to be suitable for this treatment concept. Although liquid agents may be safely delivered into the aneurysm under balloon protection, their considerable washout rate after balloon removal requires further refinements of the technique before clinical application is advisable. AUTHORS' ABSTRACT

MUSCULOSKELETAL

Musculoskeletal Radiology: Percutaneous Bio~sv of the Mus- culoskeletal ~ ~ s t / m l ~ Review of 77 Cases. Jacqueline C. Hodge. Can Assoc Radiol J 1999;50:121-125. (Royal Victoria Hospital, 687 Pine Ave. West, Montreal, QC H3A 1Al)

Objective: To analyze the accuracy of percutaneous bone and soft- tissue biopsies. Methods: A total of 77 percutaneous biopsies performed under computed tomographic or fluoro- scopic guidance over a 24-month period were reviewed. The biopsies were performed in 74 patients, 32 male and 42 female, with a mean age of 60.3 years. Results: Sixty-three bone and 14 soft-tissue biopsies were performed. No follow-up information was available for eight patients, and one patient died before an accurate diagnosis could be made. There were 44 true-positive, 17 true-negative, eight false-negative and no false-positive results. The correct diagnosis was obtained in 57 of 68 cases (83.8%). For bone biopsies, the accurate diagnosis was obtained in 47 of 55 cases (85.5%). For soft-tissue biopsies, the correct diagnosis was obtained in 10 of the 13 cases (76.9%). Diagnostic

accuracy was slightly better for osteo- lytic than for osteosclerotic lesions. Accuracy also varied with lesion site and needle type. Cytology and pathology specimens were almost equally useful in contributing to the correct diagnosis. Conclusion: The accuracy of percutaneous biopsy achieved in this series is similar to that found in other series. Although diagnostic accuracy varied, accuracy is improved if both cytologic and pathologic specimens are analyzed. AUTHORS' ABSTRACT

I CONTRAST

Prevention of Radiocontrast- Media-induced Nephropathy in Patients with Pre-existing Renal Insufficiency by Hydration in Combination with the Adenosine Antagonist Theophylline. Chris- tiane M. Erley, Stephan H. Duda, Daniela Rehfuss, et al. Nephrol Dial Transplant 1999; 14:1146-1149. (C.M.E., Associate Professor of Inter- nal Medicine, University of Tuebin- gen, Medical Section 111, Section of Nephrology and Hypertension, Ot- fried-Mueller-Str. 10, D-72076 Tuebingen, Germany)

Background: Radiographic contrast media (CM) application causes a decline in renal function, especially in patients with pre-existing renal dysfunction. In addition to hydration, several vasodilating substances have been evaluated for their ability to pre- vent renal damage after CM application. In a prospective, double-blind, placebo-controlled study we investigated the effect of the oral adminis- tration of theophylline, an adenosine receptor antagonist, on changes in renal haemodynamics and tubular injury induced by CM in well-hy- drated patients with mild-to-moderate renal insufficiency. Methods: We studied 80 patients with pre-existing chronic renal insufficiency (creatinine >1.5 mg/dL) who received more than 100 mL iopromide. Hydration (either oral or intravenous) started a t least 24 h before and lasted until 24 h after CM application. In addition, patients were randomly assigned to receive either theophylline (810 mg daily) or placebo. Serum creatinine and creatinine clearance were measured before and for 3 days after CM application. Urine was collected to measure N-acetyl-P-glucosaminidase (NAG)

Abstracts 1427

Volume 10 Number 10

enzymuria for the same period. Sixty- four patients completed the entire study protocol (theophylline, n = 35 and placebo, n = 29). Results: During the study period serum creatinine concentration and creatinine clearance did not change significantly in either group. Acute renal failure (increase of serum creatinine of a t least 0.5 mg/dL) could be observed in two

patients from the theophylline group (5.7%) and one from the placebo group (3.4%). The increase in NAG excretion reached statistical signifi- cance (P < 0.05) in the placebo group on days 2 and 3 after CM application. Conclusions: Our results indicate a role for adenosine in CM-induced tu- bulotoxicity. However, the glomerular filtration rate is preserved by hydra-

tion alone in these patients. The application of theophylline did not bring an additional benefit. The use of adenosine antagonists may be benefi- cial in patients where sufficient hydration may be impossible or in patients with a concomitant decrease in renal blood flow (eg, congestive heart failure). AUTHORS' ABSTRACT

STATEMENT OF OWNERSHIP, MANAGEMENT AND CIRCULATION (Act of August 2, 1970: Section 3685, Title 39 United States Code) Date of Filing-October 1, 1999; Title of Publication--Journal of Vascular and Interventional Radiology; Frequency of Issue-10 per year; Annual Subscription Price-$187.00; Location of Known Office of Publication-Lippincott Williams & Wilkins, Inc., 12107 Insurance Way, Hagerstown, MD 21740; Location of Headquarters or General Business Offices of the Publisher-227 East Washington Square, Philadelphia, PA 19106; Publisher-Lippincott Williams & Wilkins, Inc., 227 East Washington Square, Philadelphia, PA 19106; Editor-Daniel Picus, MD, Mallinckrodt Institute of Radiology, 510 South Kingshighway Blvd, St. Louis, MO 63110; Managing Editor-Peter T. Christy, Lippincott Williams & Wilkins, Inc., 227 East Washington Square, Philadelphia, PA 19106; Owner- Society of Cardiovascular & Interventional Radiology (SCVIR), 10201 Lee Highway, Suite 500, Fairfax, VA 22030. Known bondholders, mortgagees, and other security holders owning or holding 1 percent or more of total amount of bonds, mortgages, or other securities-none. A. Total no. copies printed (netpress run), average 4,702, actual 5,200; B. Paid circulation 1. Sales through dealers and carriers, street vendors and counter sales, average none, actual none; 2. Mail subscriptions, average 4,445, actual 4,687; C. Total paid circulation, average 4,445, actual 4,687; D. Free distribution by mail, samples, complimentary, and other free copies, average 182, actual 190; E. Free distribution outside mail (carriers of other means), average none, actual none. F. Total free distribution (sum of D and El, average 182, actual 190; G. Total distribution (sum of C and F), average 4,626, actual 4,877; H. Copies not distributed. Office use, leftover, unaccounted, spoiled after printing, average 76, actual 323. Returns from news agents, none; I. Total (sum of G and H-should equal net press run shown in A), average 4,702, actual 5,200. Percent paid andlor requested circulation, average 96%, actual 96%. I certify that the statements made by me above are correct and complete. Abbe Nelson, Director, Periodical Operations.

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