Abstracts of Current Literature

Abstracts of Current Literature

VASCULAR Diagnosis

Aortic Intramural Hemorrhage Visu- alized by Transesophageal Echocar- diography: Findings and Prognostic Implications. Susanne Mohr-Kahaly, Raimund Erbel, Peter Kearney, et al. J Am Coll Cardiol 1994; 23:658-664. (S.M.K., 11, Medical Clinic, Johannes Gu- tenberg University, Langenbeckstrasse 1, D-55101 Mainz, Germany)

Objectives. This study describes the transesophageal echocardiographic and follow-up findings in patients with aortic intramural hemorrhage. Background. Localized aortic intramural hemorrhage resulting in layered thickening of the aortic wall seems to represent a variant of acute aortic dissection without communi- cation or a typical moving intimal flap. In autopsy studies this variant, attributed to a rupture of the vasa vasorum, has been described in 5%-10% of patients with dissection. Methods. In a ~ r o s ~ e c t i v e trans- . . esophageal echocardiographic study in patients with aortic dissection ~erformed between 1986 and 1991, the diagnosis of intramural hemorrhage was established in 15 of 114 patients and confirmed either anatomically (seven patients) with an additional diagnostic imaging technique or on the basis of clear follow-up changes (eight patients). Results. Elderly patients (mean age, 70 years) with a history of hy- pertension were affected by this variant of dissection. The ascending aorta was in- volved in three patients and the descending aorta in 12. The longitudinal extent varied between 3 and 20 cm, and wall thickness varied between 0.7 and 3 cm. Classic aorta dissection developed in five patients (33%) and rupture in four (27%). Regression of aortic wall thickening was noted in two patients, whereas three patients became asymptomatic without ap- parent wall changes (33%). Surgery was performed in five patients, whereas medical therapy was continued in 10. During a mean follow-up period of 11 months, eight patients (53%) died because of complications of the aortic disease. Conclusions. In- tramural hemorrhage represents a variant of aortic dissection and may be an early finding in patients who develop classic aortic dissection or rupture. Transesopha- geal echocardiography is an excellent

method for the detection of intramural hemorrhage and for monitoring these patients. AUTHORS' ABSTRACT

Nonpenetrating Trauma to the Ca- rotid Artery: Seven Cases and a Lit- erature Review. Maria S. Li, Baird M. Smith, Jose Espinosa, e t al. J Trauma 1994; 36:265-272. (R.A. Brown, Depart- ment of Surgery, Montreal General Hospi- tal, 1650 Cedar Ave, Montreal, Quebec, H3G 1A4, Canada)

Nonpenetrating carotid trauma is un- common and frequently missed on initial examination. The cases of seven patients seen over a period of 21 years are presented, and 100 cases from the most recent literature are reviewed. Causes and mech- anisms of injury, clinical presentation, in- vestigations, management, and outcome are discussed. Causes of injury were three motor vehicle collisions, two falls, one sports injury, and one blow to the face. Clinical presentation was early in four and delayed in three. The earliest symptoms and signs were a change in mental status, headache, unprovoked fall, focal weakness, neglect, and dysphasia. Doppler studies may be useful in screening, but a defini- tive diagnosis is made with the help of angiography. Two patients were treated surgically; one died, one with delayed symptoms from a pseudoaneurysm re- covered completely. Five patients were given anticoagulants; all survived with permanent deficits related to their pretreatment neurologic status. The outcome in 100 recent cases from the literature has improved compared with previous reports. The overall mortality was 12%. The outcome in these seven cases supports recent trends toward a strategy of early anticoagulation and selective surgical treatment. AUTHORS' ABSTRACT

Extremity Gunshot Wounds: Part One - Identification and Treatment of Patients at High Risk of Vascular Injury. Gary J. Ordog, Subramanium Balasubramanium, Jonathan Wasserber- ger, e t al. J Trauma 1994; 36:358-368. (G.J.O., Department of Emergency Medi- cine, KingDrew-UCLA Medical Center, Box 227, 12021 S Wilmington Ave, Los Angeles, CA 90059)

Cost containment is important in this time of inner-city economic and health- care crisis. This article examines patients who were treated for gunshot wounds

(GSWs) of the extremities. During the study period 1978 through 1992, 16,316 patients (18,349 extremities) were treated for extremity GSWs. Nine patients with asymptomatic injuries in proximity to vascular structures who were treated before the use of duplex Doppler ultrasonography (US) were later found to have surgically treatable vascular injuries. These were identified and treated on a n outpatient basis with no long-term morbidity or mortality. With the advent of duplex Doppler US, asymptomatic vascular injuries were no longer missed. A conservative estimate of the cost savings from this study is more than $47,000,000.00. The use of duplex Doppler US and the enclosed protocols for treating asymptomatic extremity wounds prevented 16,450 needless angiograms, with a n additional savings of $32,900,000.00, for a total savings of more than $79,900,000.00. With a more liberal use of duplex Doppler US and angiography to eliminate the rare missed vascular injuries (0.09%), and the use of protocols to analyze patients with asymptomatic injuries, many extremity GSW victims (79% in this study) can be safely treated as outpa- tients, eliminating the need for expensive in-hospital observation. AUTHORS' ABSTRACT

Arterial Imaging with a New For- ward-Viewing Intravascular Ultra- sound Catheter. I. Initial Studies. James L. Evans, Kok-Hwee Ng, Michael J . Vonesh, et al. Circulation 1994; 89:712- 717. (J.L.E., 2355 N Ferguson Ave, Suite 111, Tucson, AZ 85712)

Background: Intravascular ultrasound ( I W S ) of arteries is limited by the inability of current instruments to visualize be- yond the catheter tip. The authors have developed a prototype 4-mm-diameter forward-viewing I W S catheter (Cardiovascu- lar Imaging Systems, Sunnyvale, Calif) that has the ability to provide B-mode cross-sectional ultrasound data for a distance of up to 2 cm distal to the catheter tip. Methods and Results: To study the utility of this device, a 20-MHz forward- viewing IVUS catheter was used to examine 13 arterial segments (five human femoral arteries, one human carotid artery, seven canine arteries) in vitro and one phantom. After imaging, all data were compared with histology (Histo). In all cases, the IVLJS catheter provided forward- viewing images corresponding to the arterial geometry and demonstrated vascular

660 Journal of Vascular and Interventional Radiology July-August 1994

landmarks and atherosclerotic lesions. There was a good correlation between histologically determined luminal diameters (LDs) and NUS-determined diameters for a distance of 14 mm ahead of the catheter tip: N U S LD = 1.0 Histo LD + 1.3 (r =

,871. Conclusions: These preliminary data suggest that a forward-viewing I W S catheter is feasible, accurate, and useful for evaluation of arterial geometry distal to the catheter tip. AUTHORS' ABSTRACT

Angioplasty, Atherectomy, Lasers

Directional Atherectomy with the Omnicath: A Unique New Catheter System. Wojciech Mazur, Nadir M. Ali, George P. Rodgers, et al. Cathet Cardio- vasc Diagn 1994; 31:79-84. (A.E. Raizner, Methodist Hospital, 6535 Fannin MS F- 100, Houston, TX 77030)

Omnicath is a directional atherectomy catheter that employs deflecting nontrau- matizing wires to anchor the cutting win- dow a t the atherectomy site. This anchoring system regulates the depth of cut and provides directional control and distal perfusion. The system continuously removes debris through a suction port from the operative site. To demonstrate the performance of the device, the Omni- cath was tested in the external iliac arteries of 10 atherosclerotic Hanford miniature swine in which concentric and eccentric lesions were induced. Five animals were killed 3 days after atherectomy; the remaining five animals were killed 6 weeks after the procedure. The acute histology demonstrates depth of cuts varying from partial plaque removal to near full thickness removal of the arterial wall. Histo- logic sections of the 6 week follow-up group demonstrated minimal healing response. The anchoring wires did not in- duce either acute injury or neointimal proliferation in the 6-week follow-up period. In conclusion, the Omnicath permits effective and safe atherectomy in this in- vestigative model. AUTHORS' ABSTRACT

Guidelines for Peripheral Percuta- neous Transluminal Angioplasty of the Abdominal Aorta and Lower Ex- tremity Vessels. Michael J. Pentecost, Michael H. Criqui, Gerald Dorros, et al. Circulation 1994; 89:511-531. (Office of Scientific Affairs, American Heart Associ- ation, 7272 Greenville Ave, Dallas, TX 75231-4596)

This document discusses the background and current state of peripheral angioplasty, including the prevalence of peripheral atherosclerosis and the history, clinical results, and risks of angioplasty. As a less invasive treatment, angioplasty has been placed in an awkward position between surgery and nonoperative therapy. To clarify the role of angioplasty, the determinants of success, requisite symptoms for intervention, indications for treatment, and appropriate clinical setting are described. Because the alternative treatment is typically surgery when a patient's condition necessitates intervention, the literature comparing the two treatments is reviewed. AUTHORS' EXCERPT

Angioplasty Gives Good Results in Critical Lower Limb Ischaemia: A 5- year Follow-up in Patients with Known Ankle Pressure and Diabetic Status Having Femoro-Popliteal Dil- atations. W. D. Jeans, S. E. A. Cole, M. Horrocks, et al. Br J Radio1 1994; 67:123- 128. (W.D.J., College of Medicine, Sultan Qaboos University, PO Box 35 Al Khod, Muscat 123, Sultanate of Oman)

One hundred thirty-seven consecutive patients with known ankle pressures and diabetic status underwent attempted femoro-popliteal dilation for lower limb ischaemia in an English provincial teaching hospital. All except one were followed up until failure or death to assess survival and amputation rates. Nondiabetic patients with critical limb ischaemia had a 5-year survival rate of 62.2% (SE 17.1) compared with 50.5% (SE 7.0) for claudi- cants, with no significant difference on lo- grank testing. Diabetics had a relative risk of amputation of 11.2 compared with nondiabetics. Patients with pretreatment ankle pressures of 50 mm Hg or less had a relative risk of amputation of 2.6 compared with those with higher resting pressures. It is concluded that angioplasty should be the treatment of first choice in critical lower limb ischaemia whenever it is technically possible. Including patients

with rest pain in the critical ischaemia group does not significantly affect cumula- tive patency rates. AUTHORS' ~ S T R A C T

Guidelines for Percutaneous Trans- luminal Coronary Angioplasty. Thomas J. Ryan, William B. Bauman, J . Ward Kennedy, e t al. Circulation 1993; 88:2987-3007. (Office of Scientific Affairs, American Heart Association, 7272 Green- ville Ave, Dallas, TX 75231-4596)

This report includes some general considerations that provide a brief review of the growth and development of this procedure [percutaneous transluminal coronary angioplasty], identification of contraindica- tions to its use, and a statement acknowl- edging general risks associated with angioplasty. A brief discussion of considerations unique to angioplasty follows with an enumeration of those factors currently recognized as influencing the outcome, the requirement for surgical backup, performance of angioplasty a t the time of initial catheterization, management of the patient after angioplast< the problemi of restenosis and incomplete revascularization, the need for periodic institutional credentialing, and institutional mortality and morbidity review. Lastly, specific guidelines for the application of coronary angioplasty are presented; these were developed according to anatomic (single versus multivessel disease), clinical (asymptomatic versus symptomatic patients), and physiological (presence or absence of indu- cible ischemia) considerations. The indications derived from consensus for angioplasty are judged to be either Class I, 11, or 111, based primarily on multifactorial risk assessment weighed against expected outcome, judgments of feasibility, appro- priateness to the clinical setting, and overall efficacy viewed in the light of current knowledge and technology. AUTHORS' EXCERPT

Coronary Perforation after Excimer Laser Coronary Angioplasty The Excimer Laser Coronary Angio- plasty Registry Experience. David R. Holmes, Jr, Guy S. Reeder, Ziyad M. B. Ghazzal, e t al. J Am Coll Cardiol 1994; 23:330-335. (D.R.H., Mayo Clinic, 200 First St SW, Rochester, MN 55905)

Objectiues. This study assessed the frequency of perforation with excimer coronary angioplasty. Background. Coronary artery perforation after conventional per-

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cutaneous transluminal coronary angioplasty is extremely rare. Because laser coronary angioplasty involves actual tissue ablation, it has an increased potential for perforation. Methods. All patients in the Excimer Laser Coronary Angioplasty Re- gistry were included in this prospective study. Those who had a perforation related to the procedure were compared with those who did not have this complication. Re- sults. Of 2,759 consecutive patients in the Excimer Laser Coronary Angioplasty Re- gistry, 36 (1.3%) had perforation. In these patients, the left anterior descending coronary artery was the most frequently treated vessel (53%). There were no differ- ences in fiber sizes between patients with and those without perforation. Among the patients with perforation, 36.1% required coronary artery bypass surgery, 16.7% experienced an infarction, and 5.6% had a fa- tal outcome. Among the patients without perforation, the rates were 3.1%, 3.8%, and 0.6%, respectively. However, 41.7% of the patients with documented coronary artery perforation did not need coronary artery bypass surgery or experience myocardial infarction or death. No angiographic characteristics distinguished lesions with from those without perforation. The frequency of coronary artery perforation declined over time with increasing operator experience, from 1.6% in the first 1,888 patients to only 0.4% in the last 1,000 patients (P = ,002). Conclusions. With increasing operator experience, the rate of perforation with excimer laser coronary angioplasty has decreased. When perforation occurs, subsequent event rates increase. AUTHORS' ABSTRACT

Local Effect of Serotonin Released during Coronary Angioplasty. Paolo Golino, Federico Piscione, Claude R. Bene- dict, e t al. N Engl J Med 1994; 330:523- 528. (P.G., Division of Cardiology, Second School of Medicine, Via Sergio Pansini 5, 80131 Naples, Italy)

Background. Serotonin is released after the aggregation of platelets, a phe- nomenon that may occur after coronary angioplasty. The authors sought to determine whether serotonin is released into the coronary circulation during coronary angioplasty and to assess whether serotonin can affect coronary artery tone during angioplasty. Methods. Blood samples were drawn from the ascending aorta and the coronary sinus of eight patients sched- uled to undergo angioplasty of the left anterior descending or circumflex coronary artery. Samples were obtained before an-

gioplasty and after each balloon dilation. The dimensions of arterial segments distal to the site of dilation were measured an- giographically before angioplasty and 5 and 15 minutes after the last dilation in these eight patients and in seven similar patients; the latter group was treated with ketanserin, a serotonin,-receptor antagonist, before angioplasty. Results. Before the eight patients underwent angioplasty, their mean ( 2 SE) plasma serotonin level in the aorta was 2.5 ng/mL 2 0.7 and that in the coronary sinus was 2.3 ng/mL 2 0.6 (P = .34). The serotonin level in plasma from the coronary sinus rose significantly, to 31.5 2 13.5, 17.6 + 5.3, and 29.1 2 8.1 ng/mL after the first, second, and third di- lations, respectively (P = ,014 for the comparison with preoperative levels). In contrast, the serotonin level in plasma from the ascending aorta did not change. The cross-sectional area of the coronary artery was significantly reduced 5 and 15 minutes after the last dilation (from a preoperative value of 37 mm2 2 0.5 to 2.7 mm2 2 0.4 15 minutes after the last dilation; P = ,011). This vasoconstriction was significantly blunted in the seven patients who received ketanserin (from 3.7 mm2 + 0.5 before angioplasty to 3.9 mm2 2 0.4 after 15 minutes) (P = .017 for comparison with the eight patients who did not re- ceive ketanserin). Conclusions. Serotonin is released into the coronary circulation during angioplasty, and this vasoactive substance may contribute to the occurrence of vasoconstriction distal to the dilated site. The vasoconstriction is atten- uated by ketanserin, a serotonin,-receptor antagonist. AUTHORS' ABSTRACT

Contrasting Effects of the Intermit- tent and Continuous Administration of Heparin in Experimental Resten- osis. Elazer R. Edelman, Morris J. Kar- novsky. Circulation 1994; 89:770-776. (E.R.E., Cardiovascular Division, Brigham and Women's Hospital, 75 Francis St, Bos- ton, MA 02115)

Background. Heparin inhibits proliferation of smooth muscle cells in culture and intimal hyperplasia in experimental animals but paradoxically exacerbates vascular injury in clinical trials. To determine whether the difference in the means by which heparin was administered explained the benefit in animals and aggravation in humans, the authors examined the vascular effects of a range of heparin treatments. Methods and Results. When laboratory rats were injected subcutane-

ously with heparin (55.5 IU, = 1.0 mgkg) per clinical trial protocols, intimal hyperplasia after arterial injury was exacer- bated rather than alleviated. The intima- to-media area ratio was increased 22.5% with every-other-day injections and was increased 16.8% with daily injections. When the daily dose of heparin was increased to 7.2 mgkg or when injections were initiated a week before injury, intimal hyperplasia was made even worse (52.2% and 59.9% above control). Twice- daily heparin, 7 and 17 hours apart, had no demonstrable effect one way or the other, and it was not until the heparin was administered a t 12-hour intewals that intimal hyperplasia and cell proliferation were lessened (44.6% decrease). The great- est reduction in intimal hyperplasia was obtained when the heparin was administered continuously. The continuous os- motic pump intravenous infusion of heparin inhibited 62.5% of the expected proliferation, and perivascular polymeric device release of heparin blocked the response by 74.2%. While subcutaneous injections transiently increased activated partial thromboplastin time, neither mode of continuous delivery altered coagulation. Conclusions. The authors might reconsider the use of heparin in vascular diseases and not neglect this promising compound because of inappropriate extrapolation from the laboratory to clinical use. AUTHORS' ABSTRACT

Thrombolysis

History of Drugs for Thrombotic Dis- ease: Discovery, Development, and Directions for the Future. Richard L. Mueller, Stephen Scheidt. Circulation 1994; 89:432449. (R.L.M., Starr 4 Pavil- ion/Cardiovascular Center, New York Hos- pital-Cornell Medical Center, 525 E 68 St, New York, NY 10021)

The history of the antithrombotic agents-aspirin, heparin, warfarin, and the thrombolytics-is a rich and lively od- yssey of serendipity, perseverance, vision, and conflict involving a number of striking personalities. The history of aspirin spans ages and continents from Hippocrates' an- algesic for women in labor to the rediscov- ery of the white willow bark by English country scholar Reverend Edward Stone. Bayer chemist Felix Hoffmann reinvented aspirin for his ailing father; suburban physician L.L. Craven pioneered the prophylactic antithrombotic uses of aspirin; and Sir John Vane elucidated aspirin's mecha-


nism of action as the inhibiton of prosta- glandin synthetase. Heparin was discovered by McLean, working as a medical student in 1915 in search of a pure procoagulant in dog liver. His original im- pure material differed somewhat from to- day's heparin, but purified heparin was rapidly accepted for a myriad of clinical uses; to this day, diverse new properties of this complex glycosaminoglycan continue to be elucidated. The oral anticoagulants emerged from veterinary research in the 1920s on a hemorrhagic disorder afflicting cattle that consumed spoiled sweet clover hay. Several chance encounters led Karl Link and his University of Wisconsin team to the identification of dicumarol as the of- fending agent in 1939 and its widespread therapeutic use by Wright and others in the 1940s. Link later developed warfarin as a rodenticide, but its use in humans soon followed in the 1950s. Vitamin K was discovered in the 1930s; its involvement in the mechanism of the anticoagulant agents was not delineated until the 1970s. The intrinsic ability of clotted blood to li- quify and the fibrinolytic properties of normal urine were noted in the 1800s. Tillett and Sherry's group stumbled on the fibrinolytic properties of streptokinase in the 1930s and pioneered the therapeutic use of streptokinase in the 1940s and of uroki- nase in the 1960s. Several teams found tissue-type plasminogen activator in various body sites beginning in the 1940s, leading to its cloning and widespread use in the 1980s; anisoylated plasminogen-streptokinase activator complex is an example of rational drug design. The discoverers of these diverse agents have not only provided physicians with a potent armamen- tarium of antithrombotic drugs but also helped elucidate much basic science and vividly demonstrated the merits of perseverance, independent thought, and adher- ance to the scientific method. AUTHORS' ABSTRACT

Tailored Thrombolytic Therapy: A Perspective. Maarten L. Simoons, Alfred E.R. Arnold. Circulation 1993; 88:2556-2564. (M.L.S., Thoraxcenter, Uni- versity Hospital Rotterdam, PO Box 1738, 3000 DR Rotterdam, The Netherlands)

Background. In contrast with current standard regimens, it seems more appropriate to tailor thrombolytic therapy to individual patient characteristics. A pro- posed model for such tailored therapy is based on individual assessment of benefits and risks of thrombolytic therapy, taking into account the response of individual pa-

tients to the therapy given. Methods and Results. Potential benefits of thrombolysis in individual patients can be predicted by use of demographic patient characteristics (age, sex, history of previous infarction) together with indicators of the ischemic area a t risk (total ST segment deviation) and treatment delay. With use of these pararn- eters, the number of "lives saved by thrombolytic therapy for specific patient characteristics can be estimated. Simi- larly, the risk of intracranial hemorrhage during thrombolytic therapy can be estimated from the patient's age, blood pressure a t admission, and body weight. Depending on benefitlrisk estimates, a choice can be made between regimens with high, medium, or modest thrombolytic efficacy. Continuous multilead ECG ischemia monitoring and rapid assays of myocardial proteins in serum can be used to assess the occurrence or absence of reperfusion and to detect signs of reocclusion. Such data help to decide whether thrombolytic therapy should be continued or intensified or might be discontinued in individual patients before the total standard dose has been administered. Such tailored reduction of the total thrombolytic dose will reduce the risk for bleeding complications in some of the patients. Conclusions. The concept of tailoring thrombolytic therapy and the models presented for benefitlrisk assessment should be tested in clinical studies and may subsequently help the physician to select the optimal approach in individual patients. AUTHORS' ABSTRACT

Does External Ultrasound Acceler- ate Thrombolysis? Results from a Rabbit Model. Ran Kornowski, Rich- ard S. Meltzer, Airine Chernine, et al. Cir- culation 1994; 89:339-344. (R.K., Neufeld Cardiac Research Institute, Chaim Sheba Medical Center, Tel Hashomer 52621, Is- rael)

Background. Prior in vitro and in vivo studies have reported that external ultrasound accelerates thrombolysis a t intensi- ties too low to have a direct effect on clot dissolution in the absence of a thrombolytic agent. The present study was undertaken to examine the ultrasound effect on thrombolysis and reocclusion in a rabbit thrombosis model. Methods and Results. Blood clots were produced in a femoral artery segment with endothelial damage and distal stenosis. Recombinant tissue-type plasminogen activator (rTPA) was infused a t 30 pg - kg-' . min-I for 60 minutes. Femoral artery flow was measured every 5

minutes for 2 hours. Rabbits were random- ized to four groups with continuous wave ultrasound [US] on or off with or without intravenous injection of 17 m&g of aspirin [Asp] ( + US/ - US/ + Asp/ - Asp). Ultra- sound frequency and intensity were 1 MHz and 6.3 W/cm2. In seven of eight and five of five rabbits given rTPA and - US/ - Asp or - US/ +Asp, respectively, reflow was observed, persisting to the end of the observation period. In five of nine and four of five rabbits given rTPA and + US/ - Asp or + US/ + Asp, reflow was achieved, but persistent reocclusion was subsequently observed in five of five and two of four of these rabbits, respectively. Overall, femoral artery patency was worse and reocclusion occurred more often when ultrasound was added to rTPA (P = .002 by nonpara- metric ANOVA). However, initial reflow occurred more rapidly with ultrasound ex- posure (21 minutes * 10 and 33 minutes % 6 for the +US/+Asp and +US/-Asp groups, respectively) compared to without ultrasound (46 minutes & 13 and 74 minutes e 14 for the - USl+Asp and -US/ -Asp groups, respectively) (P = .03 by ANOVA). Conclusions. Although time to initial reflow was shortened by ultrasound, it was associated with less reperfusion and more reocclusion in this model. A possible explanation for these results is ultrasound- induced platelet activation counterbalanc- ing its thrombolysis-accelerating effect. AUTHORS' ABSTRACT

H IVC Filters

Management and Prevention of Thromboembolic Events in Patients with Cance~related Hypercoagulable States: A R.isky Business. Franpis P. Sarasin, Mark H. Eckman. J Gen Intern Med 1993; 8:476486. (M.H.E., Division of Clinical Decision Making, Box 302, New England Medical Center, 750 Washington St, Boston, MA 02111)

Objective: To determine the optimal strategy for managing and preventing thromboembolic events in malignancy-associated hypercoagulable states. Design: A Markov-based decision and cost-effective- ness analysis was performed. The authors explicitly considered consequences of em- bolic and bleeding events, filter complications, and cancer-related excess mortality. Data were drawn from the current literature. The main outcome measure for each strategy was the quality-adjusted life expectancy and the total average variable costs. Subjects: Patients with advanced

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malignancies prone to develop thromboembolic events, patients with acute proximal deep venous thrombosis (DW), and patients who have survived a first episode of pulmonary embolism (PE). Interventions: The authors considered three different interventions: observation, in which neither anticoagulant therapy nor filter placement is pursued, anticoagulation, in which long- term anticoagulant therapy is started immediately, and vena caval filter. Main results: Vena caval filter was the preferred strategy for every malignancy studied, yielding an 11% gain in quality-adjusted life expectancy, compared with observation, for patients with acute D W , and an 18% gain for patients having survived a PE. Anticoagulant therapy yielded gains of 9% and 16%, respectively. Compared with anticoagulant therapy, filter was less costly due to the avoidance of additional expenses incurred by bleeding events. Pro- phylactic therapy was the least effective of the three strategies examined. Conclu- sions: Vena caval filter placement and long-term anticoagulation therapy yield similar outcomes in the setting of cancer- related hypercoagulable states. However, filter insertion is less expensive than anticoagulation. Given the short life expectancy and morbidity of patients with end- stage malignancy, patient preferences for health states must be considered in the decision-making process. If active treatment is pursued, vena caval filter should be used as a primary therapy. Prophylactic therapy is not warranted in any circum- stance. AUTHORS' ABSTRACT

Therapy of Venous Thromboembol- ism in Patients with Brain Metas- tases. David Schiff, Lisa M. DeAngelis. Cancer 1994; 73:493498. (L.M.D., Depart- ment of Neurology, Memorial Hospital, 1275 York Ave, New York, NY 10021)

Background: Deep venous thrombosis ( D W ) and pulmonary embolism (PE) are common in patients with brain metastases. Few data exist to help guide the clinician's choice between the two therapeutic options of anticoagulation and inferior vena cava filter placement. Methods: The authors reviewed their institutions' experience with the treatment of venous thromboembolism in 51 adult patients with known brain metastases since 1980. Results: Ten patients were initially treated with Greenfield filters; four (40%) had recurrent nonfatal thromboembolic events (two PE and two DW), and three required anticoagulation. Thirty-nine patients were treated initially

with anticoagulation; none of these patients later received filters. Two patients with D W were untreated, and both died of PE. Among 42 patients who received anticoagulation, the duration of anticoagulation ranged from 5 to 563 days (mean, 100 days). Two patients who received anticoagulation experienced devastating central nervous system hemorrhage in the setting of supratherapeutic anticoagulation by conventional laboratory criteria. A third patient experienced a minor deterio- ration, possibly attributable to hemorrhage, for a 7% (three of 42) incidence of serious central nervous system complications. Three asymptomatic patients developed hyperdensity within metastases on routine follow-up noncontrast computed tomographic scan, suggesting possible in- tratumoral hemorrhage. Three patients taking warfarin had recurrent DVT, with prothrombin times between 15.1 and 17.7. Systemic bleeding complications were gen- erally minor and occurred in only eight patients (19%). Conclusion: Anticoagula- tion is more effective than Greenfield filters and is acceptably safe when maintained in the therapeutic range in most patients with brain metastases and venous thromboembolism. AUTHORS' ABSTRACT

Vascular Surgery

A Prospective Study of the Determi- nants of Vein Graft Flow Velocity: Implications for Graft Surveil- lance. Michael Belkin, Kevin B. Raf- tery, William C. Mackey, et al. J Vasc Surg 1994; 19:259-267. (M.B., Department of Surgery, Brigham and Women's Hospi- tal, 75 Francis St, Boston, MA 02115)

Purpose: Serial monitoring of vein graft peak systolic flow velocity (PSFV) has been endorsed as a technique for vein graft surveillance, with low values ( c 45 cdsec) considered a marker for impending graft failure. Optimal application of this method requires an understanding of the factors affecting PSFV in normal grafts. A prospective evaluation of 46 consecutive elective infrainguinal vein grafts (six popliteal, 29 tibial, 11 pedal) was undertaken to assess the major determinants of PSFV. Methods: Factors recorded for each patient included vein graft diameter WGD), measured outflow resistance (MOR), conduit length, outflow level (poplitedtibidpe- dal), inflow level (femordpopliteal), systolic blood pressure, cardiac ejection fraction, the presence of a patent plantar

arch, and the Society for Vascular Sur- gednternat ional Society for Cardiovascu- lar Surgery resistance scoring. MOR was measured by occluding graft inflow and in- fusing saline solution through a proximal graft cannula a t 60 mL/min while simulta- neously recording the pressure a t the distal anastomosis via a separate cannula. MOR was calculated by dividing the re- sultant pressure by the infusion rate. MORs were expressed in resistance units (RUs) and were measured before and after the infusion of papaverine (MOR,,,). PSFVs and VGDs were measured 4-6 cm from the distal anastomosis 3 weeks after surgery with duplex scanning (60" angle with midstream sample volume). Results: PSFVs ranged from 22 to 148 c d s e c and averaged 83.4 c d s e c t 4.8. Pedal bypass grafts had significantly lower PSFVs (64 c d s e c + 10 vs 89.5 cmlsec + 5, P = .02) and significantly higher MOR,,, value (0.86 RUs t 0.15 vs 0.51 RUs t 0.05, P = .05) than bypasses to the poplited tibial level. When subjected to univariate analysis the factors correlating with PSFV were MOR (r = - 59 , P = .0001), MOR,PAP, (r = - .69, P = .0001), VGD (r = - .31, P = .06), Society for Vascular Surgeflnternational Society for Cardio- vascular Surgery score (r = - .35, P =

.04), inflow level (r = - .47, P = .002), and outflow level (r = - .35, P = .03). When subjected to multiple regression analysis, only MOR,,,, (P = 51 , P =

.001) and VGD (P = .14, P = .001) con- tributed significantly to the overall model (1.2 = .65, P = .0001), with MORtpAP, eliminating the effect of the other variables. The multiple regression model predicts PSFV as follows: PSFV = 176 + VGD ,,,, ( - 11.7) + MOR,,,( -63.4). Con- clusions: Clinically successful and hemo- dynamically normal vein grafts have widely variable, yet predictable, flow characteristics that are influenced primarily by outflow resistance and VGD. This wide variability suggests that no single lower threshold value for PSFV is universally applicable in identifying all grafts a t risk for failure. Detection of focal areas of flow acceleration within the graft may be more accurate in identifying grafts a t risk for failure. AUTHORS' ABSTRACT


Repeat Leg Bypass after Multiple Prior Bypass Failures. Robert D. De Frang, James M. Edwards, Gregory L. Mo- neta, et al. J Vasc Surg 1994; 19:268-277. (John M. Porter, 3181 SW Sam Jackson Park Rd, OP-11, Portland, OR 97201- 3098).

Purpose: The optimal treatment of patients with severe lower-extremity ischemia after multiple failed prior bypasses is unclear. It is presently unknown whether failure of attempted revascularization in these patients is so likely that such operation should not be elected. The authors have maintained an aggressive surgical policy of repeated revascularization regardless of prior failures. A review of their clinical experience with this diffi- cult patient group was performed to determine the results of this policy. Methods: From 1980 to 1992, 85 revascularization procedures were performed in 81 patients with lower-extremity ischemia after failure of two or more prior infrainguinal bypasses in the same leg. All patients were prospectively entered and monitored in the vascular registry. Seventy-two operations were the third procedure, six operations were the fourth procedure, and seven operations were the fifth procedure on the same extremity. Twenty-six of the 85 procedures (30%) were revisions of failing grafts discovered by routine surveillance methods, whereas 59 were replacements of thrombosed grafts. Autogenous reconstruction was used in 67 procedures (79%), and prosthetic reconstruction was used in 18 procedures (21%). The distal anastomosis was to the popliteal artery in 19 patients and infrapopliteal artery in 66. Results: The mean time to failure was 24 months for the first leg bypass and 4.9 months for the second bypass. Detailed hematologic screening revealed identifiable hypercoagulable disorders in nine (15%) of 59 patients screened after 1987. All nine had anticardiolipin antibodies. The operative mortality rate was 4%. Mean follow-up after the most recent operation was 17 months. The primary patency rate at 4 years was 79.8%. The limb salvage rate was 69.6% a t 4 years. Conclusions: These results indicate that limb revascularization after two or more failed leg bypasses results in low operative mortality rates and surprisingly good primary patency and limb salvage rates at 4 years. The patient survival rate through 4 years is un- expectedly high. In the authors' opinion

these results justify an aggressive policy of limb revascularization after multiple failed prior bypasses. AUTHORS' ABSTRACT

I GASTROINTESTINAL

A Multicenter Case-Controlled Study of Percutaneous Endoscopic Gas- trostomy in HIV-Seropositive Pa- tients. Mitchell S. Cappell, Aslam Godil. Am J Gastroenterol 1993; 88:2059-2066. (M.S.C., Division of Gastroenterology and the Department of Medicine, UMDNJ-Rob- ert Wood Johnson Medical School, New Brunswick, NJ 08903-0019)

Objectives: Malnutrition is an important cause of morbidity and mortality in patients with AIDS [acquired immunodeficiency syndrome]. Percutaneous endoscopic gastrostomy (PEG) is a safe and effective method of providing nutrition in HIV-sero- negative patients who are unable to swal- low food but have an otherwise functional alimentary tract. This study analyzes the risks and benefits of PEG in HIV [human immunodeficiency virus]-seropositive patients. Methods: The risks of PEG were analyzed in 14 consecutive HIV-seropositive patients admitted to two university hospitals, and were compared with the risks in a sex- and age-matched control group of 21 patients. Thirteen HIV patients had AIDS. Results: PEG indications included mechanical esophageal obstruc- tion in six, wasting in six, and central nervous system disorders in two. The mean weight of the HIV patients increased by 7.4% 2 3.0% (SE) 3-8 weeks after PEG. Despite advanced HIV infection, serum biochemical parameters of nutritional status remained stable a t 3-8 weeks after PEG. Nine HIV patients experienced 10 complications during a mean follow-up of 111 days 2 147 (SD). The HIV patients had six (43%) minor complications, whereas the controls had four (19%) minor complications (not significantly different, Fisher exact test). Minor complications in the HIV patients included transient tenderness and erythema a t the PEG site in four, transient pyrexia without a source in one, and transient ileus in one. The HIV patients had four (29%) significant complications, compared to none in the controls (P < .02, Fisher exact test). Significant

complications in the HIV-seropositive patients included stomal cellulitis treated with intravenous antibiotics in three, and gastric bleeding requiring transfusion of one unit of packed erythrocytes in one. None of these complications were severe; all complications rapidly resolved with therapy. The high rate of wound infection following PEG in AIDS patients, like the previously reported high rate of postoperative wound infection in AIDS patients, is attributable to immunosuppression. Dur- ing the study period, four HIV patients underwent surgical gastrostomy, with one complication of severe gastrointestinal bleeding. Conclusions: This work suggests that PEG is a useful and relatively safe method of providing long-term nutritional support in selected AIDS patients with a functional gastrointestinal tract. AUTHORS' ABSTRACT

I HEPATOBILIARY

Ultrasound Monitored Laser-induced Local Hyperthermia in the Liver: An Experimental Study on Pigs. A.M. Lofberg, D. Awidsson, T. An- dersson, e t al. Acta Radio1 1994; 35%-9. (A.M.L., Department of Radiology, Aka- demiska Sjukhuset, S-75185 Uppsala, Swe- den)

Ultrasound (US) was used to monitor the size of tissue necrosis generated by Nd-YAG [neodymium: yttrium-aluminum- garnet] laser-induced local interstitial hyperthermia and tissue coagulation in eight normal pig livers. Four treatments were done in each liver with four different energy settings. The size of the tissue necrosis measured on specimens was compared with the size measured on US. The laser energy caused a round tissue necrosis with some charring in the centre surrounded by a zone of white necrosis and a thin border of hyperaemia. A good correlation was found between the true and US-measured size of the necrosis diameters. It therefore seems possible to safely guide and monitor local laser hyperthermia in the liver with real-time US. The water-cooled quartz fibre used in this study has, however, some limitations. AUTHORS' ABSTRACT

Abstracts 665

Volume 5 Number 4

The Effect of Percutaneous Ethanol Injection Therapy on Small Solitary Hepatocellular Carcinoma Is Compa- rable to That of Hepatectomy. Kazuhiro Kotoh, Hironori Sakai, Shigeru Sakamoto, et al. Am J Gastroenterol 1994; 89:194-198. (Third Department of Internal Medicine, Kyushu University, Maida-shi 3-1-1, Fukuoka 812, Japan)

Objectives: Forty patients with solitary hepatocellular carcinoma (HCC) smaller than 20 mm in diameter were admitted to the authors' hospitals from March 1986 to December 1989. Of those 40 patients, 17 were treated with hepatectomy, 12 with percutaneous ethanol injection therapy, and 11 with the combination of percutaneous ethanol injection therapy and transcatheter arterial embolization. Method: Following up the patients after their first treatment for 2 months to 6 years, as of April 30, 1993, the authors evaluated the effects of hepatectomy, percutaneous ethanol injection therapy, and the combination of percutaneous ethanol injection therapy and transcatheter arterial embolization. Results: Of the 23 patients who did not undergo surgery, eight died from recurrence of HCC and one died from ruptured varices. Of the 14 surviving patients, 10 experienced recurrences during the follow-up period. Of the 17 patients who underwent surgery, one died in hospital and four died from recurrence of carcinoma. Of the remaining 12 patients, nine experienced recurrences. The cumula- tive survival and recurrence rates were similar in operated and nonoperated patients. There was no significant difference in these rates in patients treated with versus without transcatheter arterial embolization. Conclusion: The results showed that the efficacy of hepatectomy and the efficacy percutaneous ethanol injection therapy for small solitary HCC were similar. However, percutaneous ethanol injection therapy was safer and less expensive than hepatectomy. AUTHORS' ABSTRACT

Obstructive Jaundice Secondary to Ruptured Hepatocellular Carcinoma into the Cammon Bile Duct: Surgical Experiences of 20 Cases. M.F. Chen, Y.Y. Jan, L.B. Jeng, e t al. Cancer 1994; 73:1335-1340. (M.F.C., Department of Sur- gery, Chang Gung Memorial Hospital, ROC, 199 Tung Hwa North Rd, Taipei, 105, Taiwan)

Background. Hepatocellular carcinoma (HCC) presenting as obstructive jaundice caused by floating tumor debris in the

common bile duct is rare. Taiwan has a high incidence of HCC and cirrhosis. The authors report their clinical experiences and evaluate the results of different treatment modalities for this disease. Methods. A retrospective study was undertaken to review 20 patients with obstructive jaundice secondary to ruptured HCC into the common bile d u d during a 12-year period. Results. All patients on initial examination had recurrent episodic jaundice or cholangitis. Jaundice was relieved by nonsurgical, percutaneous transhepatic biliary stent placement in four patients and surgical intubation with T-tube drainage in 16. Types of treatment for those who were treated nonsurgically were percutaneous transhepatic biliary stent placement in two patients, followed by transcatheter hepatic arterial embolization in another two patients. For the 16 patients who were treated surgically, the types of treatment were T-tube or Y-tube drainage in 11, T- tube drainage followed by hepatic resection in two, T-tube drainage and hepatic arterial ligation in one, and T-tube drainage followed by transcatheter hepatic arterial embolization in the other two. Liver cirrhosis was the associated disease in 12 (75%). Four patients (20%) died in the hospital. The mean survival time for 12 patients who underwent only surgical or nonsurgical biliary stent placement was 3.9 months. For the three patients with percutaneous hepatic arterial embolization, the mean survival time was 8.0 months. The two patients who had undergone hepatic resection had a better postoperative survival time, with one surviving for more than 5 years. Conclusion. Clinical features, types of management, operative findings, and survival in 20 patients with HCC obstructing the common bile duct by tumor thrombi were reviewed. Not all patients with this disease were terminally ill. With proper management, good pallia- tion and occasional cure are possible. AUTHORS' ABSTRACT

Refinement of a Technique for Ther- mocholecystectomy in an Animal Model. John P. McGahan, Eric Wisner, Stephen M. Griffey, et al. Invest Radio1 1994; 29:355-360. (J.P.M., Department of Radiology, University of California Davis Medical Center, 2516 Stockton Blvd, TI- CON 11, Sacramento, CA 95817)

Rationale and Objectives. A modifica- tion of a thermal ablation system was tested for improved cystic d u d occlusion and gallbladder mucosa ablation in an animal model. Methods. Fourteen domestic

swine were included in group 1 with thermal treatment of the cystic duct to 75°C for 15 minutes, followed by heating of the gallbladder lumen with a catheterheating device to 54°C for 30 minutes. One swine served as a control (group 2). A ligature was placed around the cystic duct without thermal treatment of the cystic duct and with the catheterheating device placed into the gallbladder for 30 minutes without thermal treatment. All animals were killed after 3 weeks with histologic examination of the gallbladder, cystic dud, and surrounding organs. Results. In group 1, technical failure due to catheter clogging occurred in the first three animals, which were killed immediately. Eleven animals were treated with a redesigned catheter system. Three weeks after treatment, 10 of the 11 animals had complete cystic duct occlusion and complete obliteration of the cystic duct mucosa. One of the 11 animals experienced partial cystic d u d ablation. Nine of the 11 treated animals experienced complete mucosal ablation of the gallbladder. Five of the 11 animals had no residual lumen, whereas six of the 11 had a luminal volume that averaged 4 mL compared to 35 mL before treatment. In group 2, the control subject had a gallbladder volume of 50 mL and normal gallbladder and cystic duct mucosa. Conclusions. This study demonstrates improvement in both cystic duct occlusion and gallbladder mucosa ablation with standardization of the technique for thermocholecystectomy in an animal model. However, a better system is required to promote complete obliteration of the gallbladder lumen. AUTHORS' ABSTRACT

Effects of Biliary Endoprostheses on the Extrahepatic Bile Ducts in Rela- tion to Subsequent Operation of the Biliary Tract. Thomas M. Karsten, Paul H.P. Davids, Thomas M. van Gulik, et al. J Am Coll Surg 1994; 178:343-352. (T.M.K., Department of Surgery, St Lukes Hospital, Jan Tooropstraat 164, 1061 AE Amsterdam, The Netherlands)

Despite the widespread use of transpapillary biliary endoprostheses, little is known about their effect on the extrahepatic bile duds. In a n experimental study in dogs, the authors induced inflam- matory changes in the bile duds by stent insertion and studied the reversibility of these changes after stent removal. In addi- tion, the consequences of a period of preoperative stenting for subsequent operation of the biliary tract and the evential detri- mental effects of stenting on the histologic


factors of the liver were studied. Twenty- six mongrel dogs were randomly divided into four groups: group 1, stenting during 4 weeks; group 2, after 4 weeks stenting, construction of a hepaticojejunostomy; group 3 , 4 days of common bile duct (CBD) ligation, 4 weeks stenting and hepaticojejunostomy; and group 4, 4 days of CBD ligation and hepaticojejunostomy. All dogs were killed 2 months after the last procedure. Hepatic biopsy specimens were obtained during each procedure and bile d u d biopsy specimens were obtained during hepaticojejunostomy and after death. Four weeks of stenting of a normal or ob- structed CBD resulted in fibrosed bile ducts, showing severe chronic inflammation with papillary hyperplasia of the epi- thelium. All bile cultures grew fecal bacteria. Two months after stent removal, inflammation was still present, albeit less severe. Stenting and subsequent surgical treatment resulted in a higher incidence of postoperative complications (54%) compared with the control group (14%), although this did not reach statistical significance. Hepatic histologic factors were not markedly changed after transpapillary endoprosthesis placement, but after hepaticojejunostomy cholangiolitis was observed. Whenever transpapillary biliary endoprostheses are used, the local effects on the extrahepatic bile ducts and the subsequent bacterial contamination of the bile should be considered. AUTHORS' ABSTRACT

I GENITOURINARY

Long-term Results and Late Recur- rence after Endoureteropyelotomy: A Critical Analysis of Prognostic Factors. Paul J . Van Cangh, Jean F. Wilmart, Reinier J . Opsomer, et al. J Urol 1994; 1513934-937. (Urology Department, Cliniques Universitaires St. Luc, Avenue Hippocrate 10, 1200-Brussels, Belgium)

Of 102 consecutive endoureteropyelotomy cases followed for 1-10 years (mean, 5 years), late recurrence was observed in 13% and long-term success was achieved in 73%. Of 67 cases with an available preoperative angiogram, a strong association was noted between the existence of a vessel crossing the ureteropelvic junction and high grade hydronephrosis, and final failure and/or recurrence: Long-term success rate was 39% when both factors were present, and it was 95% when neither factor

was present. Therefore, the authors recom- mend that the presence of a vessel should be determined preoperatively since it significantly influences the outcome. AUTHORS' ABSTRACT

Arterial Priapism: Diagnosis, Treat- ment and Long-term Followup. Martin D. Bastuba, Inigo Saenz de Tejada, Caner Z. Dinlec, et al. J Urol 1994; 151:1231-1237. (Department of Urology, Boston University School of Medicine, Bos- ton, Mass)

The authors report on the long-term follow-up of seven patients, 11-50 years old, treated for arterial priapism following perineal or penile trauma with arterio- graphic evidence of contrast medium ex- travasating from a lacerated cavernous artery into surrounding erectile tissue la- cunae (an arterial-lacunar fistula). All patients underwent medical record review and completed a mailed questionnaire. The priapism erections were described as de- void of pain or tenderness, incompletely but constantly rigid, and able to increase rigidity with sexual stimulation. Bright red corporeal aspirates were observed in all cases. Color flow Doppler ultrasound (US) findings of focal areas of high flow turbulence correlated with diagnostic arte- riography (correlation coefficient 1.00). Initial treatment by mechanical or phar- macological means was unsuccessful when performed. Superselective transcatheter embolization of the ipsilateral common penile artery resolved the priapism in all cases. The interval from onset to resolution of priapism was 4-126 days. Full erectile function return was delayed from 2 weeks to 5 months, most likely from re- solving clot lysis. Full erection quality was restored in six of seven patients with persistent function and restored frequency of intercourse a t 6-67 months. Reestablished cavernous artery flow in previously embol- ized arteries was demonstrated on follow- up US. Surgical treatment was not required in any case. The authors conclude that arterial priapism occurs in the absence of neurogenic-mediated relaxation and is sustained by high oxygen tension and shear stress associated with the cavernous artery laceration. Embolization therapy offers effective management of the pathophysiology with high preservation of premorbid erectile function. AUTHORS' ABSTRACT

Antegrade Scrota1 Sclerotherapy for the Treatment of Varicocele: Tech- nique and Late Results. Roland Tauber, Nils Johnsen. J Urol 1994; 151:38&390. (Department of Urology, Barmbek General Hospital, Hamburg, Germany)

Antegrade sclerotherapy has been used since 1987 to treat patients with varicocele. The method has proved to be easy to perform, safe, economical, and effective. The treatment results in 285 patients who had undergone sclerotherapy for a total of 317 varicoceles are presented and discussed. This follow-up study revealed that 285 of the patients (91%) had no signs of recurrnet or persistent varicocele. In 57 cases of inability to conceive (42%) the partners became pregnant after antegrade varicocele sclerotherapy. Antegrade sclerotherapy represents a n alternative treatment to high ligation and retrograde sclerotherapy, as well as to laparoscopic and microsurgical procedures. AUTHORS' ~ S T R A C T

Reflections upon the Nature and Management of Intracranial and In- traspinal Vascular Malformations and Fistulae. Sean Mullan. J Neuro- surg 1994; 80:606-616. (S.M., Section of Neurosurgery, University of Chicago, 5841 S Maryland Ave, Chicago, IL 60637)

Evidence is presented that dural fistulas are preceded by sinus thrombosis and that their danger lies in arterialized venous pressure within the cranium or the orbit. Arterial side occlusion leads to recurrence, while venous side occlusion leads to permanent cure. Vein of Galen aneurysms embrace some features of cerebral arteriovenous malformations (AVMs), namely a reticulum, and some features of dural fistulas, namely evidence of previous sinus anomaly and direct drainage into a sinus. These aneurysms are also perma- nently cured by venous side thrombosis, although the dangers inherent in their reticulum demand that this be done in stages or preceded by arterial side embolization. A very limited experience with venous end occlusion of cerebral (and spinal) AVMs suggests that they, too, can be per- manently cured by venous side occlusion without excision. Their reticulum demands maximum, multistage, preliminary arterial side embolization together with intra-

Abstracts 667

Volume 5 N u m b e r 4

operative hypotension during the venous occlusion stage in order to minimize intra- cerebral hemorrhage or swelling. Sche- matic models of both fistulas and malformations are presented, together with reasons why particulate embolization is safer than glue embolization. The theory is advanced that dural fistulas, vein of Galen aneurysms, and AVMs are venous- rather than arterial-based lesions, which is consistent with the experience that permanent cure has been effected by venous side occlusion without excision in all three anomalies. It is speculated that there may be a developmental link between the AVM and the venous malformation, the AVM being essentially a fistulized venous malformation. AUTHOR'S ABSTRACT

Severe Symptomatic Vasospasm: T h e Role of Immediate Postopera- t ive Angioplasty. Peter D. le Roux, David W. Newell, Joseph Eskridge, et al. J Neurosurg 1994; 80:224-229. (P.D.I.R., De- partment of Neurosurgery, RI-20, Univer- sity of Washington, Seattle, WA 98195)

The clinical success of angioplasty for symptomatic vasospasm following sub- arachnoid hemorrhage (SAH) depends on early intervention and can best be achieved after aneurysm is occluded. How- ever, patients presenting with unsecured ruptured aneurysms and established clinical vasospasm offer a dilemma for the sur- geon. The authors describe the cases of five such patients who underwent acute clipping of aneurysms followed by immediate postoperative angioplasty between 1988 and 1992. All were referred a t least 5 days after SAH. Severe vasospasm compat- ible with the clinical presentation was confirmed a t angiography. The patients met the department's criteria for angioplasty but, because of unclipped aneurysms, were first taken to the operating room for a craniotomy and aneurysm obliteration. Angiography was repeated immediately after surgery. Arterial narrowing had pro- gressed during surgery in two patients. In all patients, postoperative mechanical dila- tation was achieved with the use of a sili- cone microballoon. Following angioplasty, transcranial Doppler ultrasound flow ve- locities and single-photon emission computed tomography evaluation indicated improved cerebral perfusion compared to

aneurysm, urgent surgical obliteration of the aneurysm followed by immediate postoperative angioplasty may be a safe and reasonable means to improve outcome. AUTHORS' ABSTRACT

The Efficacy of Endosaccular Aneu- rysm Occlusion in Alleviating Neuro- logical Deficits Produced by M a s s Effect. Van V. Halbach, Randall T. Higashida, Christopher F. Dowd, et al. J Neurosurg 1994; 80:659-666. (V.V.H., UCSF Medical Center, 505 Parnassus Ave, Rm L 352, San Francisco, CA 94143-0628)

Endovascular obliteration of intracranial aneurysms with preservation of the parent artery (endosaccular occlusion) has been advocated for patients who fail or are excluded from surgical clipping and cannot undergo Hunterian ligation therapy. To clarify the effect that endosaccular occlusion has on the presenting neurological signs, 26 patients with aneurysms and symptoms related to mass effect who underwent this therapy were followed up for a mean of 60 months. Only patients with objective neurological deficits who had not suffered a hemorrhage were included in this series. Response to therapy was classified into one of three groups: "resolved," if the patient had complete resolution of presenting signs; "improved," if significant and sustained improvement was recorded in the neurological examina- tions, and "unchanged," if no change was observed. Thirteen patients (50%) were classified as resolved, 11 (42.3%) as improved, and two (7.7%) as unchanged. A comparison of patients classified as resolved with those who were improved revealed that the former group had less wall calcification (30% vs 60%) and a shorter duration of symptoms. Patients with neurological sign resolution (62%) were more likely to have totally occluded aneurysms on late follow-up arteriograms than those who had improvement (28%) or were unchanged (0%). This study suggests that endosaccular embolization t h e r a ~ v can * "

improve or alleviate presenting neurological signs unrelated to hemorrhage or distal embolization in the majority,f cases. AUTHORS' ABSTRACT

I MISCELLANEOUS

Stereotactic Fine Needle Aspi ra t ion of Mammographic Lesions. Virginia Pressler, Thomas Namiki, John Cieply, e t al. J A m Coll Surg 1994; 178:54-58. (From the Queen's Cancer Institute, Hono- lulu, Hawaii)

Stereotaxic fine needle aspiration biopsy (FNAB) is being offered a t many cen- ters across the United States in lieu of open surgical biopsy for nonpalpable mammographic lesions. To determine how accurate this procedure is in a community hospital, the authors performed stereotaxic FNAB of 62 nonpalpable mammographic lesions using Siemens upright stereotaxic equipment. FNAB was immediately followed by hook wire localization and open biopsy. Ten lesions were histologically ma- lignant. Seven of these had been identified cytologically as atypical, suspicious, or ma- lignant. Three carcinomas were undetected by FNAB, for a sensitivity rate of 70%. There were no false-positive FNAB diag- noses. Three different radiologists performed the FNAB and localizations. The authors' results were insufficiently sensi- tive to justify offering stereotaxic FNAB to patients in lieu of open surgical biopsy. They are currently planning to evaluate the dedicated stereotaxic prone biopsy equipment to compare the results of needle core biopsies with subsequent hook wire localization and open biopsy. AUTHORS' ABSTRACT

preoperative determinations. Fo;r patients improved clinically and made a good re- covery. In this subgroup of patients presenting with proven symptomatic vasospasm and an unclipped but ruptured

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