Splenic imaging with ultrasmall superparamagnetic iron oxide ferumoxtran-10 (AMI-7227): preliminary observations.

PURPOSE: Ferumoxtran-10 (ultrasmall superparamagnetic iron oxide; Combidex, AMI-7227) is a long-circulating MR contrast agent with reticuloendothelial uptake known to enhance tissue T1 and T2 relaxation rates. The purpose of this study was to assess the effect of ferumoxtran-10-enhanced MRI in evaluating focal splenic lesions. METHOD: Eighteen patients underwent MR evaluation of the spleen. Two of these patients with exophytic normal splenic tissue (splenules) and 13 of these patients with 24 focal splenic lesions (7 cysts, 2 hemangiomas, 7 metastases, 1 infarct, 7 lymphoma) were assessed by T1-weighted gradient echo and T2-weighted fast SE MRI following intravenous administration of ferumoxtran-10 (1.1 mg of Fe/kg). Qualitative analysis involving improved lesion detection and/or characterization, additional information from postcontrast images affecting staging, and patient management was performed. Quantitative measurements of lesion-to-spleen contrast-to-noise ratio were also performed. RESULTS: Additional information was provided by ferumoxtran-10-enhanced images in 15 of 18 patients. In 8 of 15 (53%) patients, improved lesion detection (i.e., number of lesions) was obtained on contrast-enhanced images. Improved lesion visualization (i.e., conspicuity) was noted in 11 of 15 (73%) of patients. In 10 of 15 (67%) patients, postcontrast imaging provided additional information leading to lesion characterization. Staging of disease and patient management were affected in 5 of 15 (33%) and 6 of 15 (40%) patients, respectively. CONCLUSION: Ferumoxtran-10 is a promising contrast agent for the evaluation of focal splenic lesions.

Magnetic resonance imaging in patients with central nervous system pathology: a comparison of OptiMARK (Gd-DTPA-BMEA) and Magnevist (Gd-DTPA).

RATIONALE AND OBJECTIVES: The objective of the two pivotal phase 3 studies was to evaluate the safety and efficacy of OptiMARK (Gd-DTPA-bis(methoxyethylamide) [Gd-DTPA-BMEA]) compared with Magnevist (Gd-DTPA) in magnetic resonance imaging of the central nervous system. METHODS: Two multicenter, randomized, double-blind, parallel group studies were conducted in 395 patients with known or suspected central nervous system pathology. Subjects were randomized to receive a single 0.1 mmol/kg intravenous injection of either Gd-DTPA-BMEA or Gd-DTPA. The safety of Gd-DTPA-BMEA and Gd-DTPA was monitored for up to 72 hours after study drug administration. Precontrast and postcontrast administration magnetic resonance scans were acquired using identical imaging planes and techniques. RESULTS: No deaths or unexpected adverse events were reported in either group. A comparison of adverse events by intensity and relation demonstrated no statistically significant differences between the two groups. Gd-DTPA-BMEA and Gd-DTPA were equivalent with respect to confidence in diagnosis, conspicuity, and border delineation. CONCLUSIONS: Gd-DTPA-BMEA and Gd-DTPA demonstrated comparable efficacy profiles, and the safety profiles were considered similar.

Safety and efficacy of a new oral contrast agent for sonography: a phase II trial.

OBJECTIVE: Our purpose was to study the safety and efficacy of a new orally administered sonographic contrast agent in patients with suspected upper abdominal disorders. SUBJECTS AND METHODS: Ninety-nine patients with signs or symptoms suggestive of upper abdominal disorders were enrolled in a prospective range-of-dose phase II clinical trial at six sites; sonograms of 93 patients were evaluated for efficacy. Patients underwent upper abdominal sonography before and after receiving a randomized dose of the contrast agent (200, 400, 600, 800, or 1000 ml). Safety was monitored by physical examination and laboratory testing. The primary efficacy parameter was additional information provided by the contrast agent when comparing unenhanced and contrast-enhanced sonography. RESULTS: Of the 14 adverse events in 11 patients, only five, which included mild diarrhea and nausea, were considered related to the contrast agent. In 83 of 93 patients, additional information was obtained from the contrast-enhanced images. Visualization of anatomy was improved as follows: the stomach, in 82% of patients; the duodenum, in 63% of patients; the pancreatic head and body, in 61% of patients; and the pancreatic tail, in 67% of patients. CONCLUSION: SonoRx is a safe and well-tolerated contrast agent that improves the sonographic evaluation of the upper abdomen, with significant improvement in imaging the stomach, duodenum, and pancreas.

A multisite phase III study of the safety and efficacy of a new manganese chloride-based gastrointestinal contrast agent for MRI of the abdomen and pelvis.

The purpose of this study was to evaluate the safety and efficacy of a manganese chloride-based oral magnetic resonance (MR) contrast agent during a Phase III multisite clinical trial. Two hundred seventeen patients were enrolled who were already scheduled for MRI of the abdomen and/or pelvis. In this group of patients, it was postulated that the use of an oral agent would better allow discrimination of pathology from bowel. Patients with known gastrointestinal pathology including peptic ulcer disease, inflammatory bowel disease, obstruction, or perforation were excluded to minimize confounding variables that could affect the safety assessment. Of these 217 patients, 18 received up to 900 mL of placebo, and 199 patients were given up to 900 mL of a manganese chloride-based oral contrast agent, LumenHance (Bracco Diagnostics, Inc.). Safety was determined by comparing pre- and post-dose physical examinations, vital signs, and laboratory examinations and by documenting adverse events. Efficacy was assessed by unblinded site investigators and two blinded reviewers who compared pre- and post-dose T1- and T2-weighted MRI scans of the abdomen and/or pelvis. In 111 (57%) of the 195 cases evaluated for efficacy by site investigators (unblinded readers), MRI after LumenHance provided additional diagnostic information. Increased information was found by two blinded readers in 52% and 51% of patients, respectively. In 44/195 cases (23%) unblinded readers felt the additional information would have changed patient diagnosis and in 50 patients (26%), it would have changed management and/or therapy. Potential changes in patient diagnosis or management/therapy were seen by the two blinded readers in 8-20% of patients. No clinically significant post-dose laboratory changes were seen. Forty-eight patients (24%) receiving LumenHance and four patients (22%) receiving placebo experienced one or more adverse events. Gastrointestinal tract side effects were most common, seen in 29 (15%) of LumenHance patients and in 3 (17%) of the placebo patients. LumenHance is a safe and efficacious oral gastrointestinal contrast agent for MRI of the abdomen and pelvis.

Successful treatment of a renal arteriovenous fistula with a Fogarty catheter.

A large renal arteriovenous fistula developed in a 71-year-old patient after percutaneous needle biopsy. Attempts to control the fistula with autologous clot were unsuccessful. A Fogarty catheter placed fluoroscopically was used to obliterate the feeding vessel. This is the first case reported in which this technique was used to control a renal arteriovenous fistula. This method of treatment offers the advantage of avoiding major surgical intervention with precise control of the fistula.

Complications of renal cyst exploration versus renal mass aspiration.

This report presents a comparison of the complications of surgical exploration with unroofing and renal cyst puncture. Two hundred fifty-five patients were operated on, with a mortality rate of 1 per cent and a morbidity rate of 28 per cent. The complications in 63 patients examined by mass aspiration included a morbidity rate of 6.4 per cent and no mortality. The possibilities of over-looking carcinomas through cyst aspiration are weighed against the demonstrated morbidity of surgical exploration and found to be much less significant. The authors recommend that an asymptomatic renal mass that radiographically appears to be a cyst and is unaccompanied by urine changes or clinical stigmata of renal neoplasia be treated by cyst aspiration and not subjected to surgical exploration.

Computed tomography in the detection of juxtasellar lesions.

One thousand consecutive computed tomograms were reviewed to determine the accuracy of the procedure in the detection of juxtasellar lesions. The detection rate was compared to those of plain skull films, radionuclide studies, angiography, and pneumoencephalography. Computed tomography was slightly superior to angiography and was surpassed only by pneumoencephalography, both of which are invasive procedures which carry a definite risk. The data indicate that computed tomography is the screening method of choice in the detection of juxtasellar masses.

Control of arteriovenous fistula of splenic vessels by Fogarty catheter.

A large arteriovenous fistula of the splenic vessels was identified by angiography. A splenic-artery-to-splenic-vein fistula developed shortly after a staging procedure for Hodgkin disease. A second surgical procedure failed to adequately control the arteriovenous communication. Intra-arterial obliteration of the fistula was accomplished by use of a Fogarty catheter.

The detection of venous thrombosis.

It is imperative that the orthopedic surgeon recognize the magnitude of the problem of thromboembolic disease. It is the most common complication of trauma or surgical procedures. Because the clinical signs and symptoms of deep venous thrombosis are so variable, and since pulmonary embolism is often the first sign of deep venous thrombosis, we must continue to refine our techniques for screening and diagnosis. The 125-I fibrinogen localization of propagating venous thrombi in the legs is a very promising and sensitive screening procedure. With refinements, the Doppler effect flowmeter and impedance phlebography may prove to be valuable screening techniques. Venography is still one of the most effective procedures in detecting venous thrombi and remains the standard of detection. The search must continue for better methods of prevention, diagnosis, and treatment.