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As part of a new heavy ion preinjector that will supply beams for the Relativistic Heavy Ion Collider and the National Aeronautics and Space Administration Space Radiation Laboratory, construction of a new electron beam ion source (EBIS) is now being completed. This source, based on the successful prototype Brookhaven National Laboratory Test EBIS, is designed to produce milliampere level currents of all ion species, with q/m=(1/6)-(1/2). Among the major components of this source are a 5 T, 2-m-long, 204 mm diameter warm bore superconducting solenoid, an electron gun designed to operate at a nominal current of 10 A, and an electron collector designed to dissipate approximately 300 kW of peak power. Careful attention has been paid to the design of the vacuum system, since a pressure of 10(-10) Torr is required in the trap region. The source includes several differential pumping stages, the trap can be baked to 400 C, and there are non-evaporable getter strips in the trap region. Power supplies include a 15 A, 15 kV electron collector power supply, and fast switchable power supplies for most of the 16 electrodes used for varying the trap potential distribution for ion injection, confinement, and extraction. The EBIS source and all EBIS power supplies sit on an isolated platform, which is pulsed up to a maximum of 100 kV during ion extraction. The EBIS is now fully assembled, and operation will be beginning following final vacuum and power supply tests. Details of the EBIS components are presented.

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OBJECTIVE: The purpose of this study was to describe our successful experience with high-dose intraarterial urokinase therapy in treating acute, life-threatening vertebrobasilar occlusion. CONCLUSION: We successfully treated five patients with acute vertebrobasilar occlusion who presented up to 24 hr after the onset of symptoms. Higher doses of urokinase than are commonly reported in the literature were used in this series at a rapid infusion rate with a "pulse-spray" technique. The result was prompt thrombolysis and good clinical outcome.

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OBJECTIVE: Our purpose is to show that a combination of imaging techniques and periodic radiologic follow-up offers an alternative to biopsy in certain patients with long bone surface osteomas. CONCLUSION: Asymptomatic lesions that are consistent with osteoma on a combination of imaging studies can be followed up clinically and radiographically, allowing patients to avoid unnecessary biopsies.

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Fifty consecutive patients who had a history and clinical findings consistent with internal derangement of the wrist were prospectively entered into a study to compare the findings of triple-injection arthrography with those of arthroscopy of the wrist with use of three portals. Twenty-six patients were men, and twenty-four were women. They had an average age of thirty-six years (range, eighteen to seventy years). The average duration of symptoms in the wrist was eight months (range, one to twenty-four months). The arthrograms of the wrist, which included cineradiographs, were all made and evaluated by the same radiologist. The arthroscopic evaluation of the wrists was performed by two hand surgeons who had previous knowledge of the arthrographic findings. The abnormal findings included in this study were limited to those that should be detectable with both arthrography and arthroscopy. These were full-thickness tears of the scapholunate ligament, the lunotriquetral ligament and the triangular fibrocartilage. The findings of arthrography were normal in eighteen wrists, demonstrated a single lesion in twenty-one, and demonstrated multiple lesions in eleven. Twelve wrists were noted to have a tear of the scapholunate ligament; fifteen, a tear of the lunotriquetral ligament; and eighteen, a tear of the triangular fibrocartilage. The arthroscopic findings were normal in six wrists, demonstrated a single lesion in twenty-five, and demonstrated multiple lesions in nineteen. Twenty-two wrists were noted to have a tear of the scapholunate ligament; fifteen, a tear of the lunotriquetral ligament; and thirty, a tear of the triangular fibrocartilage. When compared with arthroscopy of the wrist, the sensitivity, specificity, and accuracy of triple-injection cinearthrography in detecting tears of the scapholunate ligament, lunotriquetral ligament, and triangular fibrocartilage, as a group, were 56, 83,and 60 per cent. Although arthrography of the wrist is a well accepted diagnostic modality in the evaluation of pain in the wrist, this study suggests that normal arthrographic findings do not necessarily rule out the possibility of internal derangement of the wrist.

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PURPOSE: To assess the outcome of percutaneous placement of Wallstents for treatment of hemodynamically significant diffuse stenoses (> 3 cm in length), chronic occlusions, failed angioplasty procedures, and flow-limiting dissection in the iliac arteries. MATERIALS AND METHODS: Lesions in 94 iliac limbs were treated in 66 patients. Indications for stent placement included claudication in 49 limbs and limb-threatening ischemia in 45. Forty-two limbs were treated for diffuse disease, 39 for chronic occlusion, nine for failed angioplasty, and four for flow-limiting dissection. RESULTS: Technical success was achieved in 86 of 94 limbs (91%), with major complications in 9% of patients. One death occurred within 30 days (not procedure-related). Ankle-brachial indexes improved from 0.51 +/- 0.24 to 0.76 +/- 0.22 (P < .001). Eighty-five percent demonstrated improvement under Rutherford criteria. Follow-up was obtained up to 38 months (mean, 14 months +/- 8). Cumulative primary patency rates were 78% at 1 year and 53% at 2 and 3 years (standard error 10%). Secondary patency rates were 86% at 1 year and 82% up to 32 months (standard error > 10% after 32 months). No significant decrease in mean ankle-brachial index was observed during follow up. No difference in primary patency was observed based on lesion type, symptom severity, lesion location, or runoff status. The limb salvage rate for patients with limb-threatening ischemia was 98% at a mean follow-up of 14 months +/- 7. CONCLUSIONS: Technical success and complication rates for percutaneous iliac artery revascularization with use of Wallstents are favorable, symptoms improved in the majority of patients, and excellent secondary patency can be achieved. With use of Wallstents, most patients with iliac artery insufficiency as a result of long-segment disease or chronic occlusions can be treated percutaneously.

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The authors describe the clinical history of a girl with severe chronic constipation due to anterior ectopic anus, associated with supernumerary nipples. The authors underline the importance of possible associations between supernumerary nipples and other congenital anomalies.

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A Tc-99m bone scan of a patient with classic roentgenographic findings of osteopoikilosis revealed multiple foci of increased activity that corresponded to many of the sclerotic foci on the roentgenograms. The authors presume that the abnormal bone scan in this patient reflects active osseous remodeling, similar to what has been observed in bone islands. Previous reports have emphasized the critical role of the radionuclide bone scan for distinguishing osteopoikilosis from osteoblastic bone metastases in patients with a known or suspected primary malignancy. In a young patient, an abnormal bone scan does not exclude the diagnosis of osteopoikilosis if the roentgenographic findings are characteristic of that entity.

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Retrospective review of percutaneous abscess drainage (PAD) of 335 abscesses in 323 consecutive patients was undertaken. Particular attention was directed to body location, associated organ system, communications and fistulae, and to the underlying immunologic status of the patient. One-year follow-up was available in all patients. Overall, the cure rate was 62.4% (209 of 335 abscesses), with a failure rate of 8.95% (30 of 335 abscesses). There were 14.2% (46 of 323 patients) deaths in the follow-up period, of which 4.6% (15 of 323 patients) were believed attributable to sepsis or septic complications. The overall complication rate was 9.8% (33 of 335 abscesses), most of which were minor in nature. For the patient exhibiting immunocompromise, representing 53.1% (172 of 323 patients) of the patient population, the cure rate was 53.4% (95 of 178 abscesses), which was significantly lower than the cure rate of 72.6% (114 of 157 abscesses) for the immunocompetent patient population (n = 151) (P less than .001). The recurrence rate was 2.1% (seven of 335 abscesses), with all recurrences within 3 months of initial drainage. PAD is effective and permanent treatment for both immunocompromised and immunocompetent patients.

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Results of percutaneous drainage performed in eight patients with eight liver abscesses with intrahepatic biliary communication and 22 patients with 26 liver abscesses without biliary communication were analyzed to determine whether the presence of an intrahepatic biliary communication affected the outcome of treatment. The clinical features and response to treatment of both groups were compared. The presence or absence of biliary communication was determined by injection of contrast material into the abscess under fluoroscopic guidance either during or several days after initial drainage. Duration of drainage was longer (p less than .05) in patients with communication (range, 7-44 days; mean, 22 days) than in patients without communication (range, 1-33 days; mean, 13 days). Percutaneous drainage was curative in five (63%) and palliative or temporizing in one (13%) of eight patients with communication. It was curative in 15 (68%) and palliative or temporizing in five (23%) of 22 patients without communication (p = .317). Liver abscesses with intrahepatic biliary communication did not require percutaneous transhepatic biliary diversion for cure. Despite longer duration of drainage for abscesses with intrahepatic biliary communication, the cure rates of percutaneous drainage for both groups were similar. Patients in whom an intrahepatic biliary communication was shown did not require alternative interventional or surgical measures for cure.

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Six patients with extensive hand and forearm thromboembolic disease were treated by means of intraarterial infusion of urokinase, with good clinical results. Four significant complications occurred, including a possible stroke. Embolization of pericatheter thrombus was a possible etiologic factor in this case. Antegrade brachial artery puncture should be used in the setting of prolonged upper extremity thrombolytic therapy to avoid the cerebral vasculature. Thrombolysis is an effective technique for tissue salvage in cases of inoperable hand thrombosis.

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Pertinent radiologic and surgical literature regarding abscess drainage was reviewed. Noted is the heterogeneity of disorders categorized as abscesses, and the variety of therapeutic approaches presently available. Specific abscesses are discussed based on body location and/or associated organ system.

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Although biliary fistulae and bilomas are often adequately managed with percutaneous drainage, persistent bile duct leaks are difficult to control. The primary surgical goal in this situation is to decompress the biliary system through diversion of bile flow to facilitate healing of the defect in the bile ducts. We report 3 patients with large biliary duct defects who underwent percutaneous transhepatic cholangiography which demonstrated the site of the biliary leakage. Then, extrapolating the aforementioned surgical tenet to these patients, all 3 were successfully treated with interventional radiologic techniques: simultaneous percutaneous transhepatic biliary diversion to control biliary flow and percutaneous biloma drainage to facilitate closure of the cavity.

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The purpose of this study was to determine the efficacy of percutaneous drainage of renal and perirenal abscesses. Thirty-two abscesses, 10 renal and 22 renal with perirenal extension, in 30 patients (16 female, 14 male; age range, 5-83 years), were drained percutaneously. Twenty-one patients had had surgery recently and/or were immunosuppressed. Ten of the 13 postoperative patients had had surgical procedures involving the urinary tract. Size of the abscesses ranged from 10 to 650 ml, and all were drained via CT or fluoroscopic guidance. The type of drainage catheter used depended on the size of the abscess. Complications were unusual. A transient febrile episode without sequelae within the first 12 hr of catheter placement was the most common complication. All patients had their abscess catheter placed while in the hospital; 12 (40%) subsequently were followed up (2-50 days) as outpatients until their catheters were removed without complications. Percutaneous drainage alone was curative in 20 patients (67%) as determined by resolution of signs and symptoms or follow-up CT. Eight (27%) had improvement of signs and symptoms but required surgery to remove tumor (one patient) or a poorly functioning or nonfunctioning kidney (five patients), perform open pyelolithotomy (one patient), or drain a loculated abscess (one patient); all eventually were cured. Three patients (10%) with multiple medical problems died before resolution could be documented, although death was not thought to be directly related to failure of therapy. Our results indicate that percutaneous drainage alone is curative in the majority of cases of renal and perirenal abscesses. Many patients can be treated safely, in part, on an outpatient basis.

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