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ABSTRACT: Three patients with either a history of severe allergic reactions to iodinated contrast or marked renal insufficiency underwent
interventional uroradiologic procedures using full-strength gadodiamide (Gd) as a contrast agent in place of iodinated contrast
material. The procedures were percutaneous access for nephrostolithotomy, antegrade pyelography with placement of a nephroureteral
stent, and a diagnostic nephrostogram with exchange of a nephroureteral stent. Gd was visualized fluoroscopically and produced
satisfactory digital radiographs without allergic reaction or worsening renal function. Gd can be useful in guiding interventional
uroradiologic procedures when iodinated contrast material is contraindicated.
CardioVascular and Interventional Radiology 04/2012; 23(1):72-75. · 2.09 Impact Factor
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ABSTRACT: To describe the appearance of lower extremity runoff vessels following subintimal recanalization (SIR) on contrast-enhanced magnetic resonance angiography (ceMRA) and compare 2 different ceMRA techniques.
A total of 6 patients underwent stepping table 3-dimensional (3D) ceMRA and time-resolved 2-dimensional (2D) MRA within 1 to 3 days (mean 1.83 days) following SIR. The 2 techniques were compared with intra-arterial digital subtraction angiography (DSA).
A total of 15 arteries were recanalized in 6 patients. Three-dimensional ceMRA allowed evaluation of patency in all segments above the knee. Postprocedural hyperemia impaired the assessment of the trifurcation vessels on 3D ceMRA. Due to its higher temporal resolution 2D MRA was not affected by venous contamination and allowed reliable confirmation of patency of the recanalized vessels.
Diagnostic MRA studies of the lower extremity runoff vessels following SIR is possible, but a hybrid technique using a stepping table MR DSA and a time-resolved sequence like 2D MRA of the calf station is necessary for runoff assessment.
Vascular and Endovascular Surgery 04/2010; 44(3):223-31. · 0.99 Impact Factor
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CardioVascular and Interventional Radiology 04/2010; 33(5):1064-5. · 2.09 Impact Factor
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Klaus D Hagspiel,
Kiran Nandalur,
Timothy L Pruett,
Daniel A Leung,
J Fritz Angle, David J Spinosa,
Alan H Matsumoto,
Hossam Ahmed,
Hilary A Sanfey,
Robert G Sawyer,
Brian Burkholder,
Kenneth L Brayman
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ABSTRACT: To retrospectively evaluate high-spatial-resolution contrast material-enhanced three-dimensional (3D) magnetic resonance (MR) angiography for assessment of vascular complications of pancreas allografts.
The institutional review board approved the study and waived the requirement for informed patient consent owing to the retrospective nature of the study with use of an anonymous-subject database. The study was HIPAA compliant. The clinical and MR angiography findings in 11 patients (eight men, three women; mean age, 43 years; age range, 30-54 years) who had a history of pancreatic transplant dysfunction and underwent a total of 13 contrast-enhanced 3D MR angiography examinations were retrospectively reviewed. Comparison with conventional angiography findings was possible for four MR angiography examinations, comparison with surgical findings was possible for two examinations, and clinical follow-up was possible for all examinations. Two observers in consensus and blinded to the clinical results performed image analysis of the arterial and venous segments. Classification agreement was assessed with quadratic weighted kappa statistics.
Ten MR angiography examinations revealed vascular complications or signs suggestive of rejection. Only three examinations were considered to have completely normal results. All major complications were detected and included complete or partial arterial graft occlusion, stenosis of the arterial Y-graft caused by a kink, complete venous thrombosis, and arteriovenous fistula with pseudoaneurysm formation. For 46 arterial segments and 15 venous segments with angiographic and/or surgical comparison, overall agreement with MR angiography findings was nearly perfect (mean kappa, 0.983; standard error of the mean, 0.128).
High-spatial-resolution MR angiography of pancreas allografts enables assessment of the arterial and venous vascular anatomy and can be used to reliably identify clinically relevant vascular complications.
Radiology 03/2007; 242(2):590-9. · 5.73 Impact Factor
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Klaus D Hagspiel,
Sabah Butty,
Kiran R Nandalur,
Eric A Bissonette,
Ming-Chen Paul Shih,
Daniel A Leung,
J Fritz Angle, David J Spinosa,
Alan H Matsumoto,
Hossam Ahmed,
Hilary Sanfey,
Ross B Isaacs,
Robert G Sawyer,
Timothy L Pruett
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ABSTRACT: The aim of this study was to determine whether magnetic resonance urography without pharmacological (diuretic) stimulation and mechanical compression allows conclusive evaluation of the urinary system in potential renal donors. In 28 consecutive patients magnetic resonance urography (MRU) was performed on a 1.5-T system. Two techniques, rapid acquisition with relaxation enhancement (RARE) and a gadolinium (Gd)-enhanced 3D fast low angle shot (FLASH) sequence were compared in the absence of adjunctive measures. Two reviewers assessed image quality, presence of artifacts and completeness of visualization of the collecting systems and ureters. Among the 53 MR urograms, there was no difference in image quality and presence of artifacts between RARE and Gd-MRU. Despite high image quality, visualization of the urinary collecting system was insufficient. Continuous visualization from the collecting system to the distal ureter was demonstrated bilaterally in only 14% of the RARE and 26% of Gd-enhanced MR urograms, respectively. Overall, Gd-enhanced MRU was superior to the RARE technique in displaying the segments of the urinary collecting system, but this difference was not found to be statistically significant. Neither the RARE technique nor the gadolinium-enhanced MRU technique is accurate enough to allow the evaluation of the collecting system and ureters in potential renal donors in the absence of pharmacological intervention and compression.
European Radiology 12/2005; 15(11):2230-7. · 3.22 Impact Factor
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ABSTRACT: Previous formulations of cyanoacrylate, though very effective, proved to have too high a tissue reactivity to be used internally. A novel cyanoacrylate compound with less tissue reactivity was recently developed. The objective of this study was to assess this novel cyanoacrylate compound for the use as vascular suture line sealant.
Twelve adult female sheep received a 6 mm PTFE interposition graft in each iliac artery, for a total of 24 grafts. Using oxidized cellulose (Surgicel) as a control, two formulations of a new cyanoacrylate compound (named "compound A" and "compound B") were assessed during this trial. Hemostatic efficiency was measured at the time of operation by the assessment of bleeding time and amount of blood loss. Long-term graft patency was assessed angiographically at 4, 6, and 18 months. Tissue reaction at 2 weeks, 1, 6, and 18 months was assessed grossly by vascular surgeons and microscopically by a blinded pathologist.
Average time to hemostasis was 37.6, 50.6, and 219 s in group A, group B, and oxidized cellulose control groups, respectively (P<or=0.001 for both compounds versus control). There were no significant differences between groups with regards to graft patency. Histopathology analysis demonstrated mild to moderate tissue reaction at 2 weeks and 1 month in the cyanoacrylate groups compared with controls at 1 month (ANOVA P=0.004). Mild tissue reaction was seen at 6 months and 18 months, with no significant differences between groups (ANOVA P=0.08, 0.62, respectively).
The novel cyanoacrylate compound examined in this study is a highly effective suture line sealant with only mild tissue reactivity and no significant effects on graft patency when studied over an 18 month period.
Journal of Surgical Research 06/2005; 125(2):161-7. · 2.25 Impact Factor
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Klaus D Hagspiel,
Kiran Nandalur,
Brian Burkholder,
J Fritz Angle,
Kenneth L Brayman, David J Spinosa,
Alan H Matsumoto,
Olivia L Veldhuis,
Hilary Sanfey,
Robert G Sawyer,
Timothy L Pruett,
Daniel A Leung
American Journal of Roentgenology 03/2005; 184(2):465-73. · 2.78 Impact Factor
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David J Spinosa,
Nancy L Harthun,
Eric A Bissonette,
Dorothy Cage,
Daniel A Leung,
John F Angle,
Klaus D Hagspiel,
John A Kern,
Ivan Crosby,
Harry A Wellons,
Gary D Hartwell,
Alan H Matsumoto
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ABSTRACT: To describe the technique of subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) to improve technical success for the performance of subintimal recanalization when there is failure to reenter the distal true lumen or when there is a limited segment of patent distal target artery available for reentry.
Subintimal recanalization was attempted in an antegrade direction in all patients. If reentry into the distal true lumen was unsuccessful or a short segment of target artery was present, retrograde access was obtained in the distal target artery (popliteal, anterior tibial/dorsalis pedis, or posterior tibial) and a retrograde subintimal channel was created. A guide wire was used to connect the retrograde and antegrade subintimal channels simultaneously to create a "flossing" guide wire. The subintimal tract was dilated with balloon angioplasty with or without stent implantation. Limb salvage, amputation-free survival, and survival rates over time were determined.
The SAFARI technique resulted in successful subintimal recanalization creating straight-line flow to the foot in all 21 limbs in 20 patients in which the technique was attempted. Antegrade-retrograde access was performed with the femoral artery and the following vessels: popliteal, n = 11; anterior tibial/dorsalis pedis, n = 10; and posterior tibial, n = 2 (two limbs involved multiple accesses). All procedures were successful. The limb salvage rate with SAFARI was 90% (95% CI, 74%-100%) at 6 months.
The SAFARI technique can be useful for completing subintimal recanalization when there is failure to reenter the distal true lumen from an antegrade approach or when there is limited distal target artery available for reentry. The SAFARI technique improves technical success in the performance of subintimal recanalization. Limb salvage rates are comparable to those with antegrade subintimal recanalization.
Journal of Vascular and Interventional Radiology 02/2005; 16(1):37-44. · 2.08 Impact Factor
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ABSTRACT: The objective of our study was to evaluate the in vitro and in vivo 3D contrast-enhanced MR angiography characteristics of a new platinum-based balloon-expandable stent system and compare this system with a variety of competing metallic stents.
All experiments were performed on 1.5-T scanners. In vitro experiments were performed using 10 stents implanted into a custom-built phantom. Different orientations of the stents along the magnetic field and multiple flip angles were examined. In addition, 19 patients underwent contrast-enhanced MR angiography after the implantation of 36 stents, including four patients with six platinum stents. Angiographic correlation was available for all 19 patients, and luminal patency and stent-induced artifacts were assessed quantitatively.
Of the tested balloon-expandable stents, only the platinum-based stents created artifact causing luminal narrowing of 30% or less. All other balloon-expandable stents induced larger artifacts that resulted in higher degrees of narrowing. Thus, if patent, the platinum-based stents allow significant in-stent stenosis to be ruled out reliably. Selected nitinol- or tantalum-based self-expandable stents also are suitable in this regard.
Of the tested devices, platinum-based stents are the only type of currently available balloon-expandable stent that creates 30% or less artifact-induced apparent stenosis and thus are suitable for MR angiography.
American Journal of Roentgenology 02/2005; 184(1):288-94. · 2.78 Impact Factor
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ABSTRACT: Pseudoaneurysm formation is a serious vascular complication of pancreatitis. It most commonly affects splenic and gastroduodenal arteries. We report a rare case of superior mesenteric artery pseudoaneurysm in a child with hereditary pancreatitis. Multidetector CT angiography allowed the comprehensive assessment of the aneurysm and allowed accurate surgical planning obviating the need for catheter angiography.
Pediatric Radiology 09/2004; 34(8):656-9. · 1.67 Impact Factor
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David J Spinosa,
Daniel A Leung,
Alan H Matsumoto,
Eric A Bissonette,
Dorothy Cage,
Nancy L Harthun,
John A Kern,
John F Angle,
Klaus D Hagspiel,
Ivan K Crosby,
Harry A Wellons,
Curtis G Tribble,
Gary D Hartwell
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ABSTRACT: To review percutaneous intentional extraluminal recanalization (PIER) for treatment of patients who are poor candidates for infrainguinal arterial bypass surgery (IABS) and have arterial occlusions and chronic critical limb ischemia (CCLI).
Patients with CCLI who were poor candidates for IABS were candidates for PIER. PIER was performed to create continuous arterial flow to the foot for limb salvage. PIER was attempted in 40 patients (22 men, 18 women; median age, 69 years; age range, 44-87 years). Of these patients, 24 (60%) had diabetes, 17 (42%) had renal disease, and 26 (66%) had coronary artery disease. Wound healing was evaluated at follow-up. Kaplan-Meier curves were constructed to evaluate limb salvage, survival, and amputation-free survival.
Fifty procedures were attempted in 44 limbs. Tissue loss was present in 40 (91%) limbs, and rest pain was present in four (9%); technical success occurred in 38 (86%). Thirty-seven (84%) of 44 limbs treated with PIER involved tibial vessels (tibial vessels only, n = 15; tibial and superior femoral artery [SFA] and/or popliteal vessels, n = 22). Sixty-six infrainguinal arterial vessel segments (SFA, n = 29; tibial, n = 37) in 38 limbs (1.7 segments per limb) were successfully treated with PIER. Thirty-five (95%) of 37 tibial occlusions and 24 (83%) of 29 SFA and/or popliteal occlusions were longer than 10 cm. Median run-off scores were 5.3 (range, 3-8) and 6.6 (range, 3-9) for patients with tibial occlusions and SFA and/or popliteal occlusions, respectively, as scored with modified Rutherford weighting of run-off arteries. Median follow-up was 7.8 months (range, 1-24 months). Twelve months after PIER, Kaplan-Meier analysis showed limb salvage rate was 66%, survival rate was 71%, and amputation-free survival rate was 48% in these patients. The 30-day mortality rate was 2.5%. Major complications occurred in four (10%) patients, and minor complications occurred in an additional four (10%).
PIER is a useful percutaneous technique for limb salvage in patients with CCLI.
Radiology 09/2004; 232(2):499-507. · 5.73 Impact Factor
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ABSTRACT: Subintimal recanalization is a percutaneous technique that allows revascularization in patients with limb-threatening ischemia. It was first described by Bolia (Cardiovasc Intervent Radiol 13;357-63:1990) but has not gained widespread use in the United States. Twenty-five patients with 32 threatened limbs were referred from a single surgeon's practice over a 23-month period. All patients were either high-risk surgical patients, due to severe medical comorbidities, or not surgical candidates due to poor target vessels, lack of appropriate conduit, or failed previous surgical revascularizations. The average age of patients was 69. There were 15 men and 10 women treated. Subintimal recanalization was immediately successful in 30 limbs. One peri-procedural death occurred, although this patient underwent a surgical bypass graft procedure in the same hospitalization. Three significant complications occurred (myocardial infarction, ventricular arrhythmia, and gastrointestinal hemorrhage). Primary patency is 83 per cent. Secondary patency is 90 per cent. Limb salvage rate is 88 per cent. Mean follow-up period is 10 months. Eight patients died in the follow-up period due to unrelated causes.
The American surgeon 07/2004; 70(6):479-82; discussion 482-3. · 1.28 Impact Factor
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Journal of Vascular and Interventional Radiology 07/2004; 15(6):645-7. · 2.08 Impact Factor
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ABSTRACT: Subintimal recanalization can be a useful procedure in selected patients with severe peripheral vascular disease with tissue loss or rest pain and limited surgical bypass options. Technical failure occurs in approximately 20% of patient who undergo percutaneous intentional extraluminal recanalization due to inability to reenter the distal true lumen. A technique to improve technical success when performing subintimal recanalization when there is failure to reenter the distal true lumen or possibly when there is a limited segment of patent distal target vessel for reentry is proposed. Further evaluation of this technique is necessary to confirm its safety and determine its technical and clinical success.
Journal of Vascular and Interventional Radiology 12/2003; 14(11):1449-54. · 2.08 Impact Factor
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ABSTRACT: Intravascular stents play an increasingly important role in the treatment of iliac artery occlusive disease and their use has expanded the indications for percutaneous endoluminal therapies. The past several years have seen a sharp increase in the number of commercially available covered and uncovered stents. Knowledge of their design and mechanical properties is crucial for selecting the appropriate stent for a particular type of lesion. In this article, the indications for and results of iliac artery stent placement are reviewed and the various characteristics of the currently available stents that may influence operator choice for use in specific lesions are discussed.
Journal of Vascular and Interventional Radiology 03/2003; 14(2 Pt 1):137-52. · 2.08 Impact Factor
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ABSTRACT: Gadolinium is useful as an alternative contrast agent for diagnostic angiographic and interventional procedures in patients with renal insufficiency or a history of a severe reaction to iodinated contrast material. Gadolinium usually is used as a "problem solver" to answer specific diagnostic questions or guide interventional procedures that cannot adequately be defined with CO2 angiography. Because of dose limitations with Gd, careful planning is required prior to its use with angiography or interventional procedures.
Radiologic Clinics of North America 08/2002; 40(4):693-710. · 2.59 Impact Factor
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ABSTRACT: MRA has evolved from a research tool to a robust clinical diagnostic modality. In many centers worldwide, it is the technique of choice for evaluating patients with suspected CMI, assessing operability of patients with pancreatic cancer, and investigating the portal system. Evolving indications include the assessment of liver transplant patients before and after transplant and of living related liver transplant donors. The search for the bleeding source in patients with gastrointestinal hemorrhage may be an indication in the future, once intravascular contrast agents become available.
Radiologic Clinics of North America 08/2002; 40(4):867-86. · 2.59 Impact Factor
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ABSTRACT: During, the past decade. MRA has evolved from an cxperimental technique into the modality of choice for the noninvasive evaluation of renovascular disease. The recent widespread application of MRA for these indications has been driven primarily by the advent of 3D contrast-enhanced MRA. which provides a fast, reliable technique for imaging large vascular territories and generates images, after postprocessing, similar in appearance to digital subtraction angiography. The cross-sectional volumetric nature of contrast-enhanced MRA affords some advantages over conventional catheter angiography. Although 3D contrast-enhanced MRA forms the backbone of vascular MR studies, several adjunctive sequences are employed to maximize the diagnostic yield of the examination. For example. flow-dependant imaging is used to complement the morphologic images of contrast-enhanced MRA by providing hemodynamic information. As such, MRA is unique among noninvasive imaging modalities in that it offers a comprehensive evaluation of anatomy and function. The availability and reliability of MRA extend renal artery screening to a wider spectrum of patients. Current applications of renal MRA range from detection of renal artery stenosis to evaluation for renal transplant donors.
Radiologic Clinics of North America 08/2002; 40(4):847-65. · 2.59 Impact Factor
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ABSTRACT: MRV offers unique diagnostic possibilities for detection and characterization of venous disease. It allows evaluation of perivascular and vascular anatomy, evolution of thromboembolic events, and assessment of vascular flow. MRI is a diagnostic tool that can be tailored for a variety of clinical dilemmas, not only DVTs. Continued improvements in hardware and software will expand the role of MRV.
Radiologic Clinics of North America 08/2002; 40(4):899-919. · 2.59 Impact Factor
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ABSTRACT: Gadolinium has physical properties that are well suited for radiographic imaging. Digital subtraction angiography with a gadolinium chelate as contrast medium can provide images of suitable quality for diagnosis and intervention. The overall safety profile of gadolinium-based contrast media is excellent. In particular, these contrast media are well tolerated in patients with renal insufficiency when administered intraarterially in doses of less than 0.3-0.4 mmol per kilogram body weight, with a decreased incidence of contrast medium-induced nephropathy, as compared with similar volumes of iodinated contrast material. The currently available formulations of gadolinium chelates can be injected safely into every arterial and venous structure. However, substantial data are lacking on the intraarterial use of gadolinium in patients with renal insufficiency, particularly at doses that exceed those routinely used in magnetic resonance angiography. Gadolinium chelates in appropriate volumes are useful alternative contrast media in selected high-risk patients undergoing angiographic studies.
Radiology 06/2002; 223(2):319-25; discussion 326-7. · 5.73 Impact Factor
