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: The Society of Cardiovascular and Interventional Radiology: 17th Annual Scientific Meeting, April 1992 Elizabeth


The 17th annual scientific meeting of The Society of Cardiovascular and Interventional Radiology (SCVIR) was held April 4-6, 1992, at the Washington Hilton and Towers, Washington, DC. More than 2000 people attended the conference, which included the traditional plenary sessions (seven sessions, 37 lectures); presentation of more than 120 scientific papers in 23 scientific sessions, a total of 67 workshops, and three award presentations, as well as new features such as five “Controversy and Consensus” conferences, three “Special Focus” sessions, and five refresher courses. Special highlights of the meeting included the Dotter lecture (a humorous, nostalgic look at the history of coronary angiography presented by Kurt Amplatz) and the honoring of Sven Ivan Seldingen as the recipient of the 1 992 Pioneer in Interventional Radiology


The Young

by Moni Stein (Toronto, paper



Ontario, Facet


Canada), Fusion:




use of shunts





frequently in papers, plenary lectures, and workshops. Also offered was the most recent information on interventional radiology ofthe hepatobiliary tract, genitourinary and gastrointestinal systems, vascular structures, and spine, head, and neck. Talks were presented on new diagnostic and therapeuI





of Roentgenology,


and abdominal


AJR page limitations, to provide of all the excellent features of this

SCVIR program. However, the following pages contain summanes of the presentations that we hope will give the reader some specific up-to-date information, as well as a general idea about the high quality of the meeting content. Included are eight presentations of original scientific research (including that given by the winner of the Young Investigator Award), two of the plenary session lectures, two of the discussions presented at one of the five “Controversy and Consensus” conferences, and Senator Mitchell’s talk on legislative health care reform.



ence” (see description below). Also, Senator George Mitchell (Maine), majority leader of the US. Senate, spoke about national health-care issues (see brief summary below). A wide range of topics was covered in the various parts of the conference program. New technology, particularly MR angiography




who presented Preliminary

tic techniques for treating nancies. We are unable, within

Interventional Intracerebral

Neuroradiology Embolotherapy

In a plenary lecture, Van V. Halbach (San Francisco, CA) discussed the use of platinum microcoils for intracerebral embolotherapy. Types now used include straight (0.2-1.5 cm); circular (helical, 0.3-3.0 cm); complex (flower, 2-8 mm); fibered; electrothrombotic; and custom-designed (e.g., for the vein of Galen) platinum coils. The coil can be delivered by one of several methods, such as injection or a specially designed Teflon pusher; some coils are electrolytically detachable. In the neurovascular system, possible applications of the coils

Ste. 103, 2223 Avenida de Ia Playa, La Jolla, CA 92037.

Editor’s note.-”Meeting News” articles report the highlights of important national radiology meetings. The articles will not undergo the peer review usually required of AiR publications, nor will they offer a critique of the information provided. The sole purpose of the series is to provide Journal readers with succinct, substantive, and accurate reviews of topics of current interest, written in a readable fashion and published promptly after the meeting. AJR 159:639-645,


1992 0361-803X/92/1593-0639

©American Roentgen Ray Society



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include intracranial aneurysms, arteniovenous malformations, vein of Galen malformations, direct fistulas, dural fistulas, and traumatic dissections. There are several advantages to using the platinum rather than steel coils: they are more nadiodense and softer; they are available in a wider range of sizes; they are nonferromagnetic and therefore MR compatible; and they can

be delivered




by means

of smaller

catheters. Dr. Halbach and his group have successfully used platinum transvenous coils to treat 58 patients with cavernous dural fistulas; 81 % of the patients were cured and the other 19% improved. Recently, 25 aneurysms diagnosed at the University of California, San Francisco, were treated with an electrolytically detachable platinum coil (the Guglielmi detachable coil); these coils show promise because they are extremely soft and will conform to the shape of any aneurysm. As future directions for research on neuroradiologic use of platinum coils, investigators need to define better the effects of electrothrombosis,

to develop


added to the coils, and to produce (a snare is now being developed),



that can be

coils that are retrievable larger, and both stiffer (for

and softer (for aneurysms).

Major Complications Procedures

in Interventional


(Boston, MA) and colleagues (I. Nakahara, L. R. M. Crowell) reviewed the records from 670 over a 5-year period. Major complications oc-

curred in 20 patients (3%): seven (1 %) of the patients died, two had life-threatening events that resolved without permanent damage; and 1 1 (2%) suffered permanent major deficits-of these 1 1 , two survived only because of the efficient, timely



of the staff in intensive

care unit (ICU). These

researchers looked for the probable cause of each of the 18 complications that led to death or permanent damage (information in parentheses is the diagnoses and outcome for the patients involved): Nine were probably caused by thrombosis (two aneurysms, seven artenovenous fistulas; two deaths, three fair condition). Five were probably caused by hemorrhage (four aneurysms, one arteriovenous fistula; four deaths, one good condition). Emboli and low flow were the probable


in two each of the other four major

Further showed

review of the circumstances of each complication technical problems in nine cases, less-than-adequate


of coagulation




status in five cases, and intra- or in four cases.



are devastating-to the patient, to the patient’s family, and to the medical team. In general, Dr. Pile-Spellman recommends a “5-C” approach when such complications occur: communicate, confess, concentrate, control, and cooperate. If reaction to a complication is not quick enough, the result is often disastrous (“it usually takes two mistakes to make a catastrophe”), so an efficient, dedicated ICU staff is absolutely critical to the successful treatment of complications from these procedures. The lessons learned from this record re-



view included “fix what you break,” “don’t go anywhere you can’t get back to,” “the staff members in the ICU are angels,” and “no one knows the patient like you do.” Four specific procedural changes have occurred at Dr. Pile-Spellman’s institution as a result of the study: (1) hepanin is routinely used to provide anticoagulation; (2) the neurologic ICU is routinely used; (3) more celebration occurs when procedures go well; and (4) schedules are more closely controlled so that proper time and attention is given to each patient.



of Dural



T. P. Smith (San Francisco, CA) presented another of the interventional neuroradiology scientific papers; thrombolysis as an alternative to anticoagulation or surgery for treatment of dural sinus thrombosis was investigated by Dr. Smith and his coworkers

(R. T. Higashida,

S. L. Barnwell,

C. F. Dowd,

Fraser, V. V. Halbach, G. B. Hieshima). In six patients ranging in age from 25 to 71 years old, dural sinus thrombosis K. W.

was treated

with a thrombolytic





presented with headache and/or papilledema; the causes of the dural sinus thrombosis (duration, 1-24 weeks) were dural arteniovenous fistulas in three patients, postoperative complications in two, and postpartum problems in one. In all six patients, the transjugular approach was used, transfemoral angiography

To investigate the causes of and lessons from complications of interventional neuroradiologic procedures, John M. Pile-Spellman Hacein-Bay, procedures


was performed

to monitor

the thrombolytic


cedure, and an introducer sheath and 3-French catheter were employed for dural sinus venography. The thrombolytic agent (urokinase) was delivered directly into the dural sinus by a constant infusion (average 60,000 units/hr); two of the six patients received boluses of 100,000 and 40,000 units, respectively.

All patients




procedure. Reasons for discontinuation of thrombolysis cluded evidence of complete clot lysis, antegrade blood and any complication. After the procedure, all patients received Coumadin apy, and all underwent follow-up studies at 6 months. of six patients showed immediate clinical improvement thrombolytic


and the improvement

surgery showed



in the sixth


initially marked


inflow, thenFour after

was confirmed

follow-up. One patient had postprocedure of a residual dural fistula (6-month follow-up the thrombolysis), follow-up showed




because improveafter

regarded as a “failure,” 6-month improvement. Only one complica-

tion occurred in this series, an early infection injection site (before the decision had been made

at a groin to consist-

ently use the transjugular approach exclusively for infusion, as this method was easier to implement); that patient was treated with antibiotics and recovered completely. No hemorrhages


In view

of the controversial


of the

two standard treatments (anticoagulation or surgery), this small series indicates that thrombolysis may be a safe and effective







These researchers believe that further research is justified and that patients should be offered this treatment before undergoing surgery. Furthermore, a new-and possibly more effective-pulse-spray technique to deliver the thrombolytic agent is now being investigated.






Facet Joint





The winner of the 1992 Young Investigator Award, Moni Stein (Toronto, Ontario, Canada), presented early findings on

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a potentially useful technique to treat facet-related back pain. His coworkers on the study were D. Elliott and J. Glen. The

general which


this study

has a lifetime



was low back

of 60-90%



an annual

incidence of 5%; of these cases of back pain, 95% are acute and only 5% are chronic-but the chronic cases account for most of the medical costs incurred. In only 10-20% of cases can a precise pathoanatomic diagnosis be established. Specifically, Dr. Stein and coworkers investigated a new concept in treating one important cause of low back pain: facet disease. The facet joint is an important stabilizing structune that carries 8-30% of the total compressive load on a lumbar spine segment. To diagnose facet joint abnormalities, several imaging techniques have been used, including plain films, conventional tomography, arthrography, nuclear medicine, CT, and MR imaging, but CT has proved to be the best techniquefor this purpose because ofthe high bone resolution it provides. Previously, facet-related back pain has been treated by orthopedic surgery and a number of relatively noninvasive procedures. The surgical fusions “leave behind a lot of hardware” and involve complications that include postoperative hematoma, extradural scar, postoperative stenosis, and recurrent herniated disk. The noninvasive procedures tried

so far (facet







and pen-

cutaneous facet joint rhizotomy) have shown better shortterm than long-term success rates. Preliminary results were presented for a new concept in treatment of facet joint abnormalities: percutaneous joint fusion of the posterior facet joints by means of a simple procedure during which nadiologic guidance is used and only local anesthetic is required. Work has been done on the first two parts of the study: (1) the testing of technical feasibility by using human cadavers and (2) preliminary studies of safety and efficacy in a canine model. In the human cadaver study, a K-wire was inserted into a facet joint and, with a bonetrephine apparatus, a bone core was removed. After a 6 x 8 mm bone plug was introduced into the facet joint oven the guidewire, CT was used to verify accurate placement of the bone plug. Successful use of this technique at two levels in the lumbar spine in one human cadaver was taken as proof of its technical feasibility. Next, a canine model was used to assess the technique because the facet joint of the dog is easily accessible percutaneously and anatomically, similar to the human facet joint. The researchers recognized four limitations of the dog model: orientation and size of facet joints in dogs are different from those of humans, biomechanics of the dog spine differ from those of the human spine, postpnocedural behavior of dogs is difficult to control, and only fusion (not clinical impact) can be checked. The procedure in the dog study consisted of a preoperative CT to measure facet depth, followed by surgery under fluoroscopic guidance to create focal destruction in the facet and to implant a bone plug. Immediate postoperative CT verified location of the bone plug, and 4- to 6-month follow-up CT checked fusion of the joint. At 6 months after surgery, the dogs were sacrificed for


of the joints.


of the canine


involving seven dogs to date, showed facet depths that ranged from 8 to 12 mm, 100% successful drilling, and 86% successful insertion of the bone plug. Overall, occurred in five of 1 2 facets (in four of six dogs):

fusion has for joints in

which bone grafts were inserted successfully, four of 10 were fused; for joints in which bone grafts were not inserted successfully, one of two was fused. Complications included one death (related to anesthetic), two epidural protrusions of bone plugs (with no neurologic sequelae), one wound infection (treated successfully with antibiotics), and two seromas. Future investigation of this technique will involve more percutaneous procedures in dogs. An important modification will involve


will be divided drilling



of facet

into three experimental

plus autograft


from iliac crest,

and drilling





plus hydroxy-

apatite bone plugs. Movement will be restricted postoperatively to facilitate fusion. If this percutaneous technique can be refined to minimize complications and create a high rate of fusion, it will have great potential usefulness for patients suffering from chronic low back pain caused by facet joint abnormalities.

Hepatobiliary Emergency Cholecystitis

Tract Percutaneous

P. D. Browning



for Acute

CA) presented

a paper

on research

performed by himself and coworkers (J. P. McGahan, E. 0. Genscovich) at the University of California at Davis Medical Center. In 49 hospitalized patients, 50 emergency percutaneous cholecystostomies were performed for acute cholecystitis. Patient







elevated WBC, and abnormal sonographic findings (i.e., the gallbladder was abnormal in appearance); the procedure was performed

in the ICU in 37 cases,

the radiology


in 10

cases, the ward in two cases, and the operating room in one case. In 35 cases, a trochar technique was used; in the other 1 5, the Seldingen


was used.

The criteria


response to the percutaneous cholecystostomy included defervescence, clinical improvement, loss of tenderness, and decrease in WBC. In all 49 patients, the sonographic findings were abnormal for the gallbladder;




(42 cases),

thickened wall (38 cases), “tense” gallbladder (34 cases in which the width of the gallbladder was >V2 of its length), pericholecystic fluid (20 cases), and gallstones (1 2 cases). In 31 of 49 patients, improvement was seen after percutaneous cholecystostomy treatment. The best responses were seen in patients




of gallstones



proved), penicholecystic fluid (80% improved), and “tense” gallbladder (74% improved). Complications of the procedure included dislodgement (two), hematoma (one), and severe pain that resolved within 1 hr (two). One attempt to perform the procedure in the ICU was unsuccessful. In emergency situations, percutaneous cholecystostomy shows strong p0tential either to provide definitive therapy on to be a tempor-



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izing procedure until surgery can be performed, and it may save the lives of some acutely ill patients in the emergency room.

Extracorporeal Percutaneous


Electrohydraulic and Endoscopic

Lithotripsy as an Adjunct Removal of Biliary Calculi


In another study concerning the hepatobiliary area, Kevin Burton (St. Louis, MO) and colleagues (D. Picus, M. E.

Hicks, M. D. Darcy, T. M. Vesely, M. A. Kleinhoffen) studied 71 patients who underwent electrohydnaulic lithotnipsy for

biliary and gallbladder calculi. Nonsurgical endoscopic) techniques frequently fail to that are impacted or very large (>1 .5 cm). tive nonsurgical methods used in these chanical




(percutaneous and treat biliary stones Currently, altennacases include me-



and fragmentation by lithotnipsy; types of lithotripsy being used are ultrasonic (limited usefulness), laser (high cost), extracorporeal shock-wave lithotnipsy, and intraconporeal electrohydraulic lithotnipsy. The latter was first developed in the former Soviet Union as a mining technique to break up large rocks: the potential difference across an electrode generates a spark that produces a cavitation bubble leading to a shock wave. In intracorporeal electrohydraulic lithotnipsy, it is used to generate energy (i.e., shock wave) inside a patient. In the 71 patients studied, the stone removal process consisted

of six steps:



(via percutaneous


lecystostomy, T-tube, ERCP, intraoperative tube during cornmon bile duct exploration, or percutaneous biliary drainage tube); dilate the tract; inspect the duct with a 1 5-French, 5mm flexible choledocoscope; implement intracorporeal electrohydraulic lithotripsy treatments; extract fragments by endoscopic

or percutaneous


and use choledoscopy


cholangiography for follow-up until the patient is stone free. The number of stones removed per patient ranged from 1 to >200, and the stones were 5-40 mm in size. In 54 patients, only one session of electrohydraulic lithotripsy was required; 1 3 patients underwent two sessions, and four patients underwent three sessions. Of all 71 patients, 31 required further stone removal after completing the electrohydraulic lithotnipsy treatments. Results showed that 97% of all stones were fragmented and that 94% of all fragments were removed. Among the five major complications were bile peritonitis leading to death (one), subendocardial myocardial infarction (one), biloma/gallbladder necrosis (two), and pneumonia/empyema (one); minor complications included exacerbation of Alzheimen’s disease, intrapenitoneal bile leak, and stitch abscess (one patient each). Of all the complications, six were related to bile duct access and none were related to the intraconporeal electrohydraulic lithotnipsy procedure itself. The advantages of intracorporeal electrohydraulic lithotripsy include its safety, low cost, and ready availability of equipment needed; moreover, the procedune is quick and relatively simple. These data seem to indicate that intracorponeal electrohydraulic lithotnipsy is a safe and effective method to improve the success of endoscopic and percutaneous stone removal.


AJR:1 59, September

The Role of Renal

and Biliary




Bruce L. McClennan (St. Louis, MO) introduced his plenary lecture with a brief chronology of the development of extracorporeal shock-wave lithotripsy (ESWL): 1948, unsuccessful attempts to fragment biliary and urinary calculi with shock waves; 1 969, attempts in the former Soviet Union to use the URAT lithotniptor for bladder calculi; 1980, first use of extracorporeal lithotnipsy by Chaussy and colleagues in Germany; 1992, about 10 manufacturers of lithotnipsy units and 200300 units installed in U. S. medical facilities. Although all types of ESWL units produce shock waves, controversy still rages over which type of generator is best (spark gap, piezoelectnic, or electromagnetic). RenaIESWL. Currently, renal ESWL is the preferred for treatment of kidney and uneteral calculi. The major

method criterion

of success is, of course, a stone-free patient, and the job of the radiologist is to inform the urologist whether the patient is stone




of patients





assessed by conventional or digital radiography (which may overestimate stone-free rates somewhat), linear tomography (which has been considered the gold standard), sonography, CT, and nephnoscopy. Studies have shown excellent results for ESWL

of small

85% for stones larger




4000 with gallstones ranging from in mean diameter), clearance rates 6 months

ESWL were only 30-50%;

1 2-month

from several 16 to 20 mm after biliary

and 1 8-month


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studies showed clearance rates of 50-85% and 50-80%, respectively. At present, no biliary lithotripsy is performed at Dr. McClennan’s institution (Mallinckrodt Institute of Radiology) because of these relatively poor results, the pain that patients experience with gallstone clearance after biliary lithotripsy, and the need for adjuvant oral bile acid therapy. Other doom-and-gloom factors affecting the usefulness of biliary lithotripsy are the competing technologies (e.g., laparoscopic cholecystectomy); the difficulty of precise stone characterization (need for pure cholesterol stones for best results); stone recurrence







reimbursement issues. Is there a future for biliary lithotnipsy? It may play a role in treating biliary/gallbladder stones in carefully selected patients, such as high-risk, elderly individuals, those with small single stones, or those with secondary gallstones (e.g., caused by rapid weight loss diets). Researchers might investigate the use of more shocks and/or higher energy to see if a change in either parameter increases efficacy of the treatment. Interventional radiologists must look carefully at the history and fate of biliary lithotripsy and consider cautiously new alternative technologies. Expressing the take-home message of his lecture, Dr. McClennan warned his colleagues to “Beware the bearer of early results” and to remember the Tarzan Principle: “Don’t let go of the first vine until the second is firmly in your grasp.”

Diagnosis Percutaneous

and Treatment Fenestration

of Aneurysms in Aortic


In a study designed to investigate the use of percutaneous fenestration for treating infradiaphragmatic ischemic complications of aortic dissections, D. M. Williams (Ann Arbor, MI) and colleagues (J. C. Andrews, M. V. Marx, G. D. Abrams) performed fenestration experiments on both human aortic specimens and canine specimens. In the human specimen study, the researchers performed percutaneous fenestration on seven aortic specimens (four dissections, one penetrating ulcer, one Marfan syndrome, one incidental infrarenal atherosclerosis) with 36 tears (transseptal in the four classic dissections, transmural in three; 31 unbiassed and five biassed). Tears were created in the human necropsy specimens and compared with tears created in five living dogs (subjects of an unrelated study). By using 8- and 1 0-mm angioplasty balloons, the investigators created transmural tears in the thoracic aorta of each dog; this transmural angioplasty caused transverse tears of the aorta that were 10% longer than the postmortem (human) tears and that were always fatal. Of the 31 unbiassed tears in the human necropsy specimens, 30 were transverse and one longitudinal; one of the biassed tears was longitudinal and one was stellate. Overall, the researchers found that percutaneous fenestration is a feasible treatment for infradiaphragmatic ischemic complications of aortic dissections and that it creates transverse tears in dissection



the results

may be unpredictable

in tears near grossly calcified plaques, supplemental balloon dilatation may be necessary, and careful patient selection will be required.



Use of Platinum Microcolls in a Rabbit Model

to Achieve



R. A. Haas (Providence, RI) and colleagues (R. Jenkins, N. Knuckey, M. Epstein) performed a study to evaluate the usefulness of the surgically created aneurysm in a rabbit model and to examine the stability of the aneurysms after treatment with platinum microcoils. In New Zealand white rabbits, 22 aneurysms (size range, 2 x 2 mm to 1 1 x 25 mm) were surgically created; 13 of the aneurysms were simple and nine were complex. The aneurysms showed little tendency to thrombose spontaneously. Via a femoral artery approach, a catheter was inserted and used for selective catheter and coil placement. Complete occlusion was defined as 90% occlusion; incomplete occlusion was

The Society of Cardiovascular and Interventional Radiology: 17th annual scientific meeting, April 1992.

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