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Dive into the research topics where Stephen L. Kaufman is active.

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Featured researches published by Stephen L. Kaufman.


Annals of Surgery | 1989

Benign postoperative biliary strictures. Operate or dilate

Henry A. Pitt; Stephen L. Kaufman; JoAnn Coleman; Robert I. White; John L. Cameron

At The Johns Hopkins Hospital from 1979 through 1987, 42 patients had 45 procedures for benign postoperative biliary strictures. Three patients were managed with both surgery and balloon dilatation. Twenty-five patients underwent surgical repair with Roux-Y choledocho- or hepaticojejunostomy with postoperative transhepatic stenting for a mean of 13.8 +/- 1.3 months. Twenty patients had balloon dilatation a mean of 3.9 times and were stented transhepatically for a mean of 13.3 +/- 2.0 months. The two groups were similar with respect to multiple parameters that might have influenced outcome. Mean length of follow-up was 57 +/- 7 and 59 +/- 6 months for surgery and balloon dilatation, respectively. No patients died after any of the procedures. The same definition of a successful outcome was applied to both groups and was achieved in 88% of the surgical and in only 55% of the balloon dilatation patients (p less than 0.02). Significant hemobilia occurred more often with balloon dilatation (20% vs. 4%, p less than 0.02). The total hospital stay and cost of balloon dilatation was not significantly different from surgery. We conclude that surgical repair of benign postoperative strictures results in fewer problems that require further therapy. Nevertheless balloon dilatation is an alternative for patients who are at high risk or who are unwilling to undergo another operation.


The New England Journal of Medicine | 1983

Pulmonary Arteriovenous Malformations: Physiologic Observations and Results of Therapeutic Balloon Embolization

Peter B. Terry; Robert I. White; Klemens H. Barth; Stephen L. Kaufman; Sally E. Mitchell

Pulmonary arteriovenous malformations can result in severe hypoxemia and dyspnea. We measured pulmonary function, arterial blood gases, and hemodynamics in 10 patients with such malformations. Pulmonary-function tests were normal, but hypoxemia was associated with chronic hyperventilation at rest (mean, 12 liters per minute; mean carbon dioxide tension, 28 mm Hg). With exercise, ventilation increased more than expected for the level of carbon dioxide production. Balloon embolization of 58 of the 71 visible vascular malformations in the 10 patients resulted in an increase in arterial oxygen tension (43 vs. 64 mm Hg; P less than 0.001) and hemoglobin saturation (79 vs. 92 per cent; P less than 0.001). Nine patients had improved exercise tolerance. Forty-eight to 72 hours after correction of the hypoxemia, resting ventilation had decreased but was still above normal (mean, 9.3 liters per minutes; mean carbon dioxide tension, 29 mm Hg). We conclude that ventilatory responses in these patients are similar to those of people from sea-level areas who are acclimated to high altitudes and that dyspnea is due to inappropriately high levels of ventilation for a given workload under hypoxic conditions.


Radiology | 1979

Embolotherapy with detachable silicone balloons: technique and clinical results.

Robert I. White; Stephen L. Kaufman; Klemens H. Barth; Vincent DeCaprio; John D. Strandbert

Catheter techniques and early clinical results of therapeutic embolization with detachable silicone rubber balloons are described in 13 patients. Effective control of post-traumatic or spontaneously occurring hemorrhage or preoperative devascularization of neoplasms was achieved in 10 patients. Three additional patients, one each with pelvic arteriovenous malformation. pulmonary arteriovenous malformation, and hemangioendothelioma of the liver, were partially treated by balloon occulsion. Therapeutic embolization with detachable silicone balloons provides a method of long-term, extremely selective arterial occlusion with reduced risks from inadvertent embolization of neighboring circulations.


Radiology | 1979

Hemodynamic significance of iliac artery stenosis: pressure measurements during angiography.

Eric J. Udoff; Klemens H. Barth; Donald P. Harrington; Stephen L. Kaufman; Robert I. White

Peak systolic pressure gradients were obtained before and after vasodilatation in 42 patients (50 limbs) with arteriographic iliac artery stenosis of questionable significance. Patients were divided into three groups according to per cent narrowing of the iliac artery. Pressure gradients across the site of stenosis tended to be significant in patients with greater than 75% stenosis (greater than or equal to 20 mm Hg) but not in patients with less than 50% stenosis; patients in the middle group (50-75% stenosis) demonstrated a wide variance. Thus the arteriogram is not an accurate indicator of hemodynamically significant lesions, particularly in patients with 50-75% stenosis where pressure measurements are of greatest value. Variations in the aortic and femoral artery systolic peak pressure occurred following vasodilatation, indicating the importance of simultaneous pressure recording.


The Journal of Urology | 1986

Comparison of recurrent varicocele anatomy following surgery and percutaneous balloon occlusion

Robert R. Murray; Sally E. Mitchell; Saadoon Kadir; Stephen L. Kaufman; R Chang; M L Kinnison; J. Walter Smyth; Robert I. White

Venography of 44 recurrent varicoceles in 37 patients demonstrated different anatomical patterns of recurrence in surgical patients (26) compared to those treated by percutaneous balloon occlusion (18). The 3 types of patterns identified included parallel, renal vein and transcrotal collateral pathways. Virtually all surgical recurrences were owing to mid retroperitoneal (27 per cent) or low (inguinal) parallel collaterals (58 per cent). The majority of post-balloon occlusion recurrences were due to either high retroperitoneal parallel (44 per cent) or renal vein collaterals (28 per cent). Surgical recurrences were treated easily with percutaneous balloon occlusion. However, 39 per cent of the patients with recurrences following balloon embolization were not anatomical candidates for repeat percutaneous occlusion. We conclude that venous collaterals are identified easily by renal venography, and knowledge of these collaterals is helpful in planning further surgical or radiological treatment.


The New England Journal of Medicine | 1980

Balloon embolization for treatment of pulmonary arteriovenous fistulas.

Peter B. Terry; Klemens H. Barth; Stephen L. Kaufman; Robert I. White

Pulmonary arteriovenous malformations associated with hereditary hemorrhagic telangiectasia are often multiple and may enlarge with time.1 Shunt-induced hypoxemia is surgically correctable when the...


Investigative Radiology | 1978

Transcatheter embolization with microfibrillar collagen in swine

Stephen L. Kaufman; John D. Strandberg; Klemens H. Barth; Robert I. White

Transcatheter embolization of the gastrosplenic and renal arteries was performed in 7 domestic swine with suspensions of microfibrillar collagen (MFC), a recently developed topical hemostatic agent. Embolized vessels remained occluded 2 days following embolization. Recanalization occurred by 14 days, although some occlusion in distal vessel persisted at 3 months. Pathologically a marked granulomatous arteritis was noted at 14 days which resolved by 3 months. Gastric ulcers or infarcts were present in two animals. The severe vasculitis and gastric pathology observed with MFC in this study would seem to preclude its use as a general embolic agent. It may be useful, however, in the preoperative embolization of neoplasms, especially in pediatric patients since its physical characteristics allow it to be easily injected through small diameter catheters.


The Journal of Urology | 1983

Therapeutic embolization of the kidney with detachable silicone balloons.

Saadoon Kadir; Fray F. Marshall; Robert I. White; Stephen L. Kaufman

Detachable silicone balloons were used for therapeutic renal artery embolization in 14 patients. Hematuria was controlled by occlusion of the arteriovenous fistulas in 6 patients and aneurysms in 3. The method was used for preoperative occlusion of the renal artery in 4 patients with renal cell carcinoma and for renal ablation in an attempt to cure hypertension in 1 additional patient. Detachable silicone balloons offer a safe and precise method for the occlusion of traumatic arteriovenous fistulas and aneurysms of the renal artery branches. Although balloon embolization also can be applied to the preoperative occlusion of renal neoplasms the conventional embolization techniques using absorbable gelatin sponge and coils are equally effective with less expense. No complications were observed in our 14 patients.


Gastrointestinal Endoscopy | 1989

Bleeding following endoscopic sphincterotomy: Angiographic management by transcatheter embolization

Mohsin Saeed; Saadoon Kadir; Stephen L. Kaufman; Robert R. Murray; Francis Milligan; Peter B. Cotton

Transcatheter embolization is a well-established and effective method for the control of bleeding from the upper gastrointestinal tract and often represents the preferred alternative to more invasive surgical management. The applications of this technique for the management of bleeding following endoscopic sphincterotomy have not been reported previously. Of five patients referred for arteriography with life-threatening postsphincterotomy bleeding, active bleeding from branches of the gastroduodenal artery was demonstrated in four. Embolization of this vessel with Gelfoam controlled the bleeding in all three patients in whom it was attempted. Arterial stenosis and spasm precluded such treatment in one patient. The fifth patient was not bleeding at the time of arteriography. There were no complications from these procedures. Our experience shows that postsphincterotomy bleeding can be safely and effectively controlled by transcatheter embolization, thereby avoiding surgery which is associated with significant morbidity and mortality in this setting.


Annals of Surgery | 1983

Percutaneous transhepatic management of complex biliary problems.

George D. Zuidema; John L. Cameron; James V. Sitzmann; Saadoon Kadir; Gardner W. Smith; Stephen L. Kaufman; Robert I. White

A series of 27 patients with complex biliary problems secondary to previous biliary operations is presented. The patients are divided into two groups: (1) patients with acute perioper-ative biliary problems; all had biliary leak with abscess, biliary cutaneous fistula, and/or stricture following cholecystectomy or common duct exploration and (2) patients with chronic postoperative biliary problems; all had previous repair of biliary stricture or injuries with late stricture formation. Early management of all patients included placement of a percutaneous biliary stent. Abscesses were drained operatively, and biliary leaks or fistulas were allowed to close spontaneously. Jaundice and cholangitis were allowed to resolve. Following stabilization, management of stricture, if present, was addressed. Eight acute patients had strictures, of which four were partial and three were dilated percutaneously. Four were complete and required operative repair. All 12 chronic patients had strictures, of which six were partial and successfully managed with percutaneous dilatation. Four patients also had common duct stones which were successfully crushed percutaneously. The authors conclude that percutaneous transhepatic drainage offers significant advantages in the early stabilization and treatment of patients with complex biliary problems, and that partial strictures of the biliary tree may be managed successfully by percutaneous dilatation.

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Saadoon Kadir

Johns Hopkins University

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R Chang

Johns Hopkins University

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M L Kinnison

Johns Hopkins University

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