Alternative Contrast Agent Research Articles

Management of Transplant Renal Artery Stenosis

Transplant renal artery stenosis is the most frequent vascular complication of transplantation. Early detection and correction reduce patients' morbidity and allograft dysfunction. Although noninvasive imaging can detect an underlying stenosis, angiography with subsequent angioplasty or stenting, or both, provides definitive diagnosis and treatment. With the introduction of alternative contrast agents and newer catheter and stent technology, these procedures can be performed safely with little risk of contrast-induced nephropathy or allograft loss.

Gadolinium as a CT Contrast Agent: An Experimental Study for the Effects of Injection Parameters in the Rabbit Brain Model

Purpose: We wanted to investigate the use of gadolinium based contrast agent (Gd- DTPA) for computed tomography (CT), and we also wanted to assess the effects of valuable injection parameters on enhancement in an experimental rabbit brain model. Materials and Methods: In vitro, attenuation measurements of serial dilutions of Gd- DTPA and iopromide were compared. In five rabbits, single level dynamic gadoliniumenhanced brain CT studies were obtained using different injection parameters. A comparison CT scan after iopromide administration was performed. The time-attenuation curves of the brain vessel and parenchyma were obtained and the magnitude of enhancement (Hmax) and the time to peak enhancement (Tmax) were analyzed. Results: In vitro, the attenuation coefficient of undiluted Gd-DTPA (2,578 HU) was higher than that of iopromide (1,761 HU) at equimolar concentrations. In 5 rabbits, the time-attenuation curve demonstrated a distinct pattern with peak enhancement only in the brain vessel, but not in the brain parenchyma. There was increasing linear relationship between the injection rate of Gd-DTPA and Hmax, and a declining linear relationship with Tmax. The higher the concentration of Gd-DTPA, the higher Hmax was, but no significant difference was found for the Tmax. Higher volumes of Gd-DTPA revealed a higher Hmax and a delayed Tmax. Conclusion: Enhancement of the brain parenchyma on gadolinium-enhanced CT is minimal, while enhancement of the brain vessels is distinctive. The most important factor affecting Hmax of the vessel is the concentration of the contrast medium and the most important factor affecting Tmax of the vessel is volume of the contrast medium. The gadolinium-based contrast agent may be an reasonable alternative contrast agent for brain CT, and especially in cerebral vessels, and it may also be advantageous for brain parenchyma of those patients with BBB dysfunction.

Gadolinium as an alternative contrast agent during cardiac catheterization in patient with iodine-induced hyperthyroidism

We report the first case of a male patient with iodine-induced hyperthyroidism and unstable angina pectoris in whom a diagnostic cardiac catheterization with gadolinium as contrast agent was chosen. N.K., a 63-year-old caucasian male, underwent percutaneous transluminal angioplasty requiring visualisation with an iodinated contrast agent. Subsequent to this intervention he developed symptomatic hyperthyroidism with persistent arrhythmia and chest pain, necessitating hospitalization. The patient was started on high dose thiamazole and propronolol. During hospitalization coronary angiography seemed necessary. As the iodine load of conventional angiography was decided to pose a high risk of thyroid storm, the procedure was performed with the non-iodine based gadolinium. Gadolinium is not nephrotoxic and does not affect thyroid function. The exam was completed without side effects, revealing no significant stenoses of the coronary arteries. Three months later, when the patient had normal thyroid levels, cardioversion succeded to revert the atrial fibrillation to sinus rhythm. Patients with iodine induced hyperthyreoidism may develop cardiac complications such as unstable angina pectoris up to an acute coronary syndrome. A diagnostic or therapeutic coronary angiography with iodinated contrast agent often aggravates hyperthyroidism. Although imaging quality with gadolinium is not as good as with iodinated contrast agent, clinically useful angiogramms can be produced. Thus, gadolinium appears to be a low risk alternative for angiography, especially in patients with overt hyperthyroidism.

Gadolinium an alternative contrast agent for sialography in patients with iodine sensitivity

The use of iodinated contrast material in radiography is contraindicated in patients with known iodine sensitivity and such patients may present a management dilemma. The successful use of gadolinium in contrast sialography is described.

Gadolinium-enhanced coronary angiography in patients with impaired renal function.

Gadolinium is a contrast agent used routinely for magnetic resonance imaging (MRI). It is safe, well tolerated and has shown no nephrotoxicity at the recommended doses. 1 Spinosa D. Matsumoto A. Hagspiel K. Angel J.F. Hartwell G. Gadolinium-based contrast agents in angiography and interventional radiology. AJR. 1999; 173: 1403-1409 Crossref PubMed Scopus (49) Google Scholar , 2 Hammer F.D. Malaise J. Goffette P.P. Mathurin P. Gadolinium Dimeglumine an alternative contrast agent for digital substraction angiography in patients with renal failure. Transplant Proc. 2000; 32: 432-433 Abstract Full Text Full Text PDF PubMed Scopus (22) Google Scholar , 3 Parodi J.C. Ferreira L.M. Gadolinium-based contrast an alternative contrast agent for endovascular interventions. Ann Vasc Surg. 2000; 14: 480-483 Abstract Full Text PDF PubMed Scopus (21) Google Scholar , 4 Spinosa D.J. Matsumoto A.H. Angle J.F. Hagspiel K.D. Leung D.A. Hartwell G.D. Gadolinium contrast agents their role in vascular and nonvascular diagnostic angiography and interventions. Tech Vasc Interv Radiol. 2001; 4: 45-52 Abstract Full Text PDF PubMed Scopus (10) Google Scholar , 5 Adding L.C. Bannenberg G.L. Gustafsson L.E. Basic experimental studies and clinical aspects of gadolinium salts and chelates. Cardiovasc Drug Rev. 2001; 19: 41-56 Crossref PubMed Scopus (106) Google Scholar Intra-arterial gadolinium has already been used to visualize small and medium size arteries. 6 Nussbaum E.S. Casey S.O. Sebring L.A. Use of gadolinium as an intraarterial contrast agent in digital substraction angiography of the cervical carotid arteries and intracranial circulation. Neurosurg. 2000; 92: 881-883 Crossref Scopus (25) Google Scholar We recently reported the use of gadolinium to perform selective intracranial angiography to visualize an aneurysm before surgical clipping. 7 Slaba S.G. El-Hajj L.F. Abboud G.A. Jebara V.A. Selective angiography of cerebral aneurysm using Gadodiamide in polycystic kidney disease with renal insufficiency. AJR. 2000; 175: 1467-1468 Crossref PubMed Scopus (14) Google Scholar The perfect tolerance of this agent encouraged us to perform the first coronary angiography that used gadolinium. 8 Sarkis A. Badaoui G. Slaba S. Moussalli A. Jebara V. Gadolinium-based coronarography in a patient with renal failure first clinical report. Cathet Cardiovasc Intervent. 2001; 54: 68-69 Crossref PubMed Scopus (19) Google Scholar The aim of this prospective report is to establish the efficacy and safety of gadolinium enhanced with low-dose nonionic contrast agents for coronary angiography in patients with impaired renal function.

Gadopentetate Dimeglumine Is Potentially an Alternative Contrast Agent for Three-Dimensional Computed Tomography Angiography with Multidetector-Row Helical Scanning

To demonstrate that gadopentetate dimeglumine is potentially an alternative contrast medium for computed tomographic angiography (CTA). One 12.2-kg Beagle dog was studied as proof of principle; the cervical vessels of three adult human patients were imaged for presurgical planning of the neck. Gadopentetate dimeglumine, 0.5 mol/l (Berlex Laboratories, Wayne, NJ, U.S.A.), a LightSpeed QX/i CT (General Electric Medical Systems, Milwaukee, WI, U.S.A.), and an Ultra Sparc II (SUN Microsystems, Santa Clara, CA, U.S.A.) running Advantage Windows 3.1 (General Electric Medical Systems) were used. Sufficient enhancement for CTA of the thoracic aorta, cervical vessels, and abdominal vessels was produced in the experimental dog, and the cervical vessels were clearly defined in all three patients. In that subset of patients with contraindications to iodinated contrast medium and for whom magnetic resonance angiography is inappropriate, gadopentetate dimeglumine may be an alternative contrast medium for CTA.

Gadodiamide as an Alternative Contrast Agent During Angioplasty in Patients With Contraindications to Iodinated Media

Gadodiamide as an Alternative Contrast Agent During Angioplasty in Patients With Contraindications to Iodinated Media

Cerebral 3D-Gadolinium-DSA in a Patient with Renal Insufficiency Presenting a Subarachnoid Haemorrhage

Contra-indications to iodinated contrast media injection are well-known and include patients with sensitivity to iodinated contrast medium, renal insufficiency, pregnancy, breastfeeding, diabetes mellitus treated by biguanides, and patients on beta-blockers1,2. When a digital subtracted angiography (DSA) is required in such patients, Gadolinium chelates have been successfully proposed as alternative contrast agents 3-12. Cerebral 3D-DSA brings crucial information in the pre-therapeutic analysis of intracranial aneurysm and is therefore highly recommended when such an abnormality is encountered. We report here a case of a non-dialysed patient with renal failure due to polycystosis, who presented with a subarachnoid hemorrhage and underwent cerebral DSA and 3D-DSA with Gadolinium as the contrast agent, to seek for, assess and then embolize two cerebral aneurysms.

Gadolinium as an alternative contrast agent for diagnostic and interventional angiographic procedures in patients with impaired renal function.

The study was designed to investigate the safety and feasibility of gadopentetate dimeglumine, a gadolinium-based contrast medium, as an alternative angiographic contrast agent in patients with impaired renal function and high risk for iodinated contrast-induced nephropathy. Gadopentetate dimeglumine was used as the radiographic contrast agent in 32 diagnostic or interventional angiographic procedures in 29 patients (59% diabetics) with severe renal insufficiency (average serum creatinine of 3.6+/-1.4 mg/dl). The average dose of gadopentetate dimeglumine was 0.34+/-0.06 mmol/kg body weight. Gadopentetate dimeglumine was used either alone (n=20) or in conjunction with carbon dioxide (n=12). Thirty-two angiographic procedures (24 diagnostic angiographies and 8 interventional procedures) were performed in 29 patients. For diagnostic purposes, eleven selective renal arteriographies, six angiographies of the iliac arteries and lower extremities, and seven venous angiographies of the upper extremity and central veins were performed. Interventional procedures consisted of two percutaneous transluminal renal angioplasties with stenting, four percutaneous peripheral vascular interventions, and two balloon angioplasties of a dialysis fistula. None of the patients, except one, had evidence of post-procedure contrast material-induced renal failure (increase in serum creatinine >0.5 mg/dl within 72 h) or other complications. This patient had a clinically important increase in serum creatinine level after percutaneous transluminal renal angioplasty and stenting, probably due to cholesterol embolism. Gadopentetate dimeglumine had sufficient radiographic density to allow adequate diagnostic visualization with digital subtraction equipment in all cases. Gadopentetate dimeglumine is an alternative and safe radiographic contrast agent for angiography and interventional procedures in patients with severe pre-existing renal impairment. In this population with high risk for contrast-induced acute renal failure, it is obviously less nephrotoxic than iodinated contrast media.

Gadodiamide as an alternative contrast agent in intravenous digital subtraction angiography and interventional procedures of the upper extremity veins.

Patients with renal insufficiency or other contraindications to iodine-based contrast agents present a significant management dilemma when angiography or interventional procedures are required. We describe the use of gadolinium as an alternative contrast agent for intravenous digital subtraction angiography (IV-DSA) and interventional procedures of the upper extremity veins. Sixteen patients with symptoms of with moderate renal insufficiency underwent digital subtraction angiography for upper extremity and subclavian venography. Angiographic studies were obtained using gadolinium as a contrast agent. In six patients we used stents. Diagnostic images were obtained in all cases. No patient suffered a complication related to the use of gadolinium, and no patient demonstrated worsened renal function after the procedure. In the setting of a contraindication to iodine-based contrast agents, gadolinium represents an important alternative contrast material that allows for the visualization of and interventional procedures in the upper extremity veins.

Einsatz von niederosmolarem Gadolinium zur angiographischen Darstellung und bei interventionell-radiologischen Eingriffen bei niereninsuffizienten Patienten

To evaluate the benefit and feasibility of gadolinium contrast agents for intra-arterial use in diagnostic and therapeutic angiography in patients with renal insufficiency. In 15 patients with planned peripheral or renal vascular interventions digital subtraction angiography with intra-arterial administration of gadolinium (gadodiamide n = 14, gadolinium-DTPA n = 1) was performed. Gadolinium was used selectively after peripheral catheter placement, mainly as an adjunct to CO2 (n = 12), to assess the distal run-off vessels or to characterize stenotic lesions. In 14 cases gadolinium yielded good or satisfactory results that were superior to those of CO2 angiography in the femoropopliteal region and calf, but also to the aorto-iliac vessels and the renal arteries. A small amount of iodinated contrast media was administered due to insufficient contrast of gadolinium in one patient. Mean serum creatinine level after angiography (295 +/- 167 micromol/l; range 125 - 764 micromol/l) was not significantly different (p >/= 0,37) from the initial level (279 +/- 149 micromol/l; range 143 - 728 micromol/l). Gadolinium is a viable alternative contrast agent for digital subtraction angiography and percutaneous transluminal angioplasty in patients with renal insufficiency. It enhances the diagnostic evaluation of stenosis and run-off vessels.

Angiographic evaluation and treatment of transplant renal artery stenosis

Transplant renal artery stenosis is an uncommon but important complication of renal transplantation. It is a potentially reversible cause of patient morbidity and allograft dysfunction, which can present both early and late in the post-transplant period. Although transplant renal artery stenosis can be detected using noninvasive imaging, definitive diagnosis and percutaneous treatment typically require the use of invasive angiographic techniques. In experienced hands, these studies can be performed safely, effectively and with a low risk of contrast induced nephrotoxicity when alternative contrast agents are used.

MR imaging of the wrist in rheumatoid arthritis using gadobenate dimeglumine.

To determine the dosage of gadobenate dimeglumine (Gd-BOPTA) necessary for MRI of rheumatoid arthritis of the wrist. Seven wrists inflamed with rheumatoid arthritis were imaged using a dedicated 0.2-T MR unit. Four cumulative dosages of 0.0125, 0.025, 0.05 and 0.1 mmol/kg body weight (BW) Gd-BOPTA were tested. Three-dimensional T1-weighted gradient-recalled echo sequences (GRE; TR: 100 ms, TE: 18 ms, flip angle 90 degrees , 4:55 min) were acquired prior to an intravenous injection and after each additional dosage of Gd-BOPTA. Relative enhancement, signal-difference-to-noise ratios (SDNRs) and the size of the inflamed tissue were quantified. Three radiologists independently evaluated the image quality, the size and the contrast of the enhancing tissue. The readers agreed on a dose of 0.05 mmol/kg BW as satisfactory for the evaluation of the size of the inflammatory tissue and for determination of bone involvement (kappa = 0.9, P < 0.001). Highly inflammatory pannus was depicted with adequate image contrast using 0.025 mmol/kg BW Gd-BOPTA. According to the SDNR and relative enhancement findings, a dose of 0.05 mmol/kg BW suffices for both off-center and centered regions of tissue inflammation (t-test, P < 0.05). Gadolinium-BOPTA is an alternative contrast agent for MRI of rheumatoid disease. This study shows that a dose of 0.05 mmol/kg BW suffices at low field strength.

Gadolinium-Based Contrast: An Alternative Contrast Agent for Endovascular Interventions

The radiocontrast substance gadoterate meglumine (Gd-DOTA) is used in magnetic resonance imaging. Because of its low rate of adverse drug reactions, we evaluated Gd-DOTA as an alternative contrast medium in diagnostic and therapeutic procedures. Twenty-three consecutive procedures were performed using undiluted contrast agent Gd-DOTA (376.9 mg/mL, Dotarem) in digital subtraction techniques. A dosage of 30-90 mL was used. Serum creatinine levels were registered before and at 24 and 48 hr after the procedure. Based on this limited experience, Gd-DOTA may be used as an alternative contrast agent in selected endovascular procedures, when iodine is contraindicated.

1,3,5-Trialkyl-2,4,6-triiodobenzenes: novel X-ray contrast agents for gastrointestinal imaging.

Examination of the gastrointestinal (GI) tract has been performed for decades using barium sulfate. Although this agent has many recognized limitations including extreme radiopacity, poor intrinsic affinity for the GI mucosa, and very high density, no alternative contrast agents have emerged which produce comparable or better contrast visualization. In fact, the various techniques of the GI radiologic examination (i.e., single contrast, double contrast, biphasic) were developed to compensate for its limitations. Each of these techniques requires complex patient manipulation to achieve adequate mucosal coating or compression to overcome the marked radiopacity of barium sulfate in order to obtain a diagnostically useful examination. A series of novel radiopaque oils, the 1,3, 5-trialkyl-2,4,6-triiodobenzenes, was designed to improve the efficacy, stability, and safety of barium formulations. These substances were prepared in two steps from 1,3,5-trichlorobenzene. Compound 17 (1,3,5-tri-n-hexyl-2,4,6-triiodobenzene), formulated as an oil-in-water emulsion, was found to be well-tolerated in rodents (mice, hamsters, rats) following acute oral and/or intraperitoneal administrations at 4 times the anticipated human clinical dose. No metabolism of 17 was detected in rat, hamster, dog, monkey, or human hepatic microsomes, suggesting the lack of oral toxicity was a consequence of poor absorption. In imaging experiments in dogs, emulsions of 17 have demonstrated excellent mucosal coating and improved radiodensity relative to barium sulfate suspensions. On the basis of the preliminary imaging and toxicity data, compound 17 was selected as a potential development candidate.

Use of gadolinium as an intraarterial contrast agent in digital subtraction angiography of the cervical carotid arteries and intracranial circulation. Technical note.

Patients with renal insufficiency or other contraindications to iodine-based contrast agents present a significant management dilemma when conventional arteriography is required. The authors describe the use of gadolinium as an alternative contrast agent for arterial digital subtraction (DS) angiography of the cervical carotid arteries (CAs) and intracranial circulation. Three patients with renal insufficiency presented with symptoms of ischemic cerebrovascular disease and inconclusive noninvasive imaging studies, which necessitated conventional angiography. Traditional transfemoral catheterization of the cervical CAs was performed and DS angiographic studies were obtained using gadolinium as an intraarterial contrast agent. In one case, selective arteriographic examination of the internal carotid arteries and vertebrobasilar system was performed as well. High-quality, diagnostic images essentially indistinguishable from routine angiographic studies were obtained in all cases. No patient suffered a complication related to the use of gadolinium, and no patient demonstrated worsened renal function after the procedure. In the setting of a contraindication to iodine-based contrast agents, gadolinium represents an important alternative contrast material that allows for excellent visualization of the cervical CAs and intracranial circulation.

Pros and cons of Barium-Impregnated Polyethylene Spheres in Gastrointestinal Disease

Barium-impregnated polyethylene spheres are an alternative contrast agent for radiographic studies of the gastrointestinal tract. The spheres are a practical, efficient, and relatively inexpensive way to diagnose a number of relatively common gastrointestinal conditions. They are most useful in the diagnosis of chronic conditions. Radiographic interpretation relies on a thorough understanding of the pathophysiology of gastrointestinal disease and how various disease states influence gastrointestinal function.

Gadolinium dimeglumine: an alternative contrast agent for digital subtraction angiography in patients with renal failure

Gadolinium dimeglumine: an alternative contrast agent for digital subtraction angiography in patients with renal failure

Gadolinium dimeglumine: an alternative contrast agent for digital subtraction angiography.

The aim of this study was to evaluate gadolinium diethylenetriaminepenta-acetic acid (Gd-DTPA) as an alternative contrast agent for digital subtraction angiography (DSA) in patients with renal insufficiency or previous anaphylactic reaction to iodinated contrast agents. We performed 34 DSAs in 31 patients by use of the commercially available 0.5-M Gd-DTPA solution (Magnevist, Schering, Berlin, Germany). The contrast material was power- or hand-injected at the same rate as iodinated contrast material, without exceeding a total amount of 0.4 mmol/kg body weight. In 18 studies Gd-DTPA was the sole contrast agent. In 9 cases gadolinium injections were combined with carbon dioxide. Restricted non-ionic contrast medium injections were administered to complete the examinations in 7 cases and for comparative purposes in 1 case. Cerebral and carotid arteries, one superior limb, abdominal aorta, renal arteries, renal transplants, iliac arteries and inferior limbs were imaged, and ten endovascular interventional procedures, including three transjugular intrahepatic percutaneous stent shunts, were performed. No side effects were observed. Diagnostic angiographic images were obtained in all cases except in 5 of the 8 distal run-off studies. Gadolinium-based contrast can produce clinically useful angiograms in patients with a contra-indication to iodine who must undergo angiography.

CO2 and gadopentetate dimeglumine as alternative contrast agents for malfunctioning dialysis grafts and fistulas

Hemodialysis grafts and native fistulas are frequently evaluated angiographically utilizing iodinated contrast material to determine the cause of malfunction. Occasionally, patients are not able to receive iodinated contrast material due to a history of previous severe allergic reaction or concern that iodinated contrast material could worsen renal function requiring premature initiation of permanent dialysis. We set out to test the feasibility of gadopentetate dimeglumine as an alternative contrast agent in conjunction with carbon dioxide (CO2) angiography in the evaluation and treatment of hemodialysis grafts and native fistulas in patients who have a contraindication to iodinated contrast material. Six patients with a malfunctioning hemodialysis graft and native fistula were evaluated. Four patients were successfully evaluated using carbon dioxide and gadopentetate dimeglumine. Two additional patients underwent balloon angioplasty using gadopentetate dimeglumine alone as the alternative contrast agent. All six patients successfully were evaluated and treated using gadopentetate dimeglumine either alone or as a supplement to CO2 angiography. Five of these patients had lesions successfully treated using gadopentetate dimeglumine alone or in combination with CO2 as the angiographic contrast agents. One patient underwent a successful diagnostic angiogram using gadopentetate dimeglumine and CO2 as alternative contrast agents and was subsequently treated with surgical revision. The gadopentetate dimeglumine angiograms identified the arterial anastomosis and more clearly identified stenotic lesions and venous outflow anatomy compared to carbon dioxide angiograms. Gadopentetate dimeglumine is useful as an alternative contrast agent in conjunction with CO2 in patients with malfunctioning hemodialysis grafts and fistulas, who have a contraindication to the administration of iodinated contrast material.