Amersham Health Research Articles

Fluoroscopically-Guided Hysteroscopic Tubal Cannulation: A Procedure for Proximal Tubal Obstruction.

To evaluate the cannulation success rate, cumulative pregnancy, and time to intrauterine pregnancy rate following fluoroscopically-guided hysteroscopic tubal cannulation (FHTC) for infertile subjects with proximal tubal obstruction. This retrospective study evaluated subjects with unilateral or bilateral proximal tubal obstruction on hysterosalpingography, who failed concomitant selective salpingography and subsequently underwent FHTC at the time of a hysteroscopy performed for findings seen on sonohysterography. FHTC employed a Novy Catheter (CooperSurgical, Inc, Trumbull, CT.) with or without the 3 French inner catheter and guidewire, to cannulate the occluded fallopian tube(s), followed by the injection of HypaqueTM (Amersham Health, Inc, Princeton, NJ.) contrast under C-arm imaging. Technical success rates, complications, post-procedure pregnancies, and average time from surgery to pregnancy were evaluated. Thirty-two women between January 1, 2017 and December 31, 2019 met the entry criteria and underwent FHTC. Of those women with bilateral obstruction, 6/6 (100%) of subjects achieved at least unilateral patency, while patency was achieved in 23/26 (88.5%) subjects with unilateral obstruction. Twenty-nine of 32 (90.6%) subjects had at least one tube successfully cannulated with 34/38 (89.5%) of proximally obstructed tubes opened. Asymptomatic tubal perforation occurred in 1/38 tubes (2.6%). Ten subjects (34.5%) achieved intrauterine pregnancies without in vitro fertilization in an average of 64.9 days from the procedure. There were no multiple pregnancies and one ectopic pregnancy. FHTC is a safe, effective, incision free procedure that results in 90% of tubes successfully cannulated, and an observed short time to intrauterine pregnancy.

Advanced Treatment Planning for Ophthalmic Plaque Brachytherapy of Uveal Melanomas

Brachytherapy (BT) treatments for uveal melanomas using ophthalmic plaques (i.e. 125I COMS and 106Ru eye plaques) achieves excellent clinical results with high tumor control and low toxicity rates. However, in comparison to state of the art external beam therapy and other BT techniques treatment planning of ophthalmologic plaque BT is underdeveloped regarding volumetric dose assessments, automated dose optimization routines and post-implantation quality assurance. The aim of this study was to (i) present a versatile and advanced treatment planning system (TPS) for ophthalmic plaque BT for both 125I COMS and 106Ru plaques and (ii) to demonstrate its potential in improving treatment planning. The TPS enables automated optimization of treatment plans based on Monte Carlo (MC) dose calculation and dose-volume histograms (DVH) as well as handling of multimodal image sets. In a first step, a resizable 3D eye model including all relevant critical structures was established, which enables to define both the tumor location and exact geometry by echography and funduscopy. Patient specific eye model adaptation can be achieved via post-implantation MR scans. An applicator library and respective dose look-up tables were generated by MC methods (MCNP6, Los Alamos, USA) that allow to generate DVHs for the target and all organs-at-risk (OAR). The current library of different plaques includes a 125I COMS plaque (Amersham Health model 6711) as well as several 106Ru plaques. The plaque geometry and 125I seeds were modeled according to AAPM TG 129 recommendations. The novel TPS allows calculating of full 3D dose distributions and DVH based on a cubic grid of 200 μm. The obtained results for the 125I COMS plaque and the values provided by AAPM TG 129 report were in good agreement. A maximum dose difference of 3 % up to a depth of 8 mm and 6 % up to a depth of 10 mm were obtained. Individualized modeling of the 3D eye based on fused funduscopic and post-implantation MR images allows to adjust treatment times and provide more accurate geometric definitions of the tumor and plaque location to improve the accuracy of the obtained DVHs. The implemented optimization routines can be used to define the optimal plaque size and safe eccentric plaque positions with respect to the tumor center to allow significant reductions of OAR doses. So far dose constrains for OARs (e.g. retinal doses of more than 500 Gy as a factor associated with visual acuity loss) were obtained from retrospective studies for treatment plan optimization. An advanced 3D TPS was developed and validated for plaque BT of uveal melanomas, which was designed to overcome the limitations of traditional treatment planning methods. The new TPS allows for a better and individualized treatment by including more image information and automated optimization into the planning process. The plaque library is currently updated to include more plaque types.

ROPES eye plaque dosimetry: commissioning and verification of an ophthalmic brachytherapy treatment planning system

In this study, the Plaque SimulatorTM eye plaque brachytherapy planning system was commissioned for ROPES eye plaques and Amersham Health model 6711 Iodine 125 seeds, using TG43-UI data. The brachytherapy module of the RADCALC® independent checking program was configured to allow verification of the accuracy of the dose calculated by Plaque SimulatorTM. Central axis depth dose distributions were compared and observed to agree to within 2% for all ROPES plaque models and depths of interest. Experimental measurements were performed with a customized PRESAGEm 3-D type dosimeter to validate the calculated depth dose distributions. Preliminary results have shown the effect of the stainless steel plaque backing decreases the measured fluorescence intensity by up to 25%, and 40% for the 15 mm and 10 mm diameter ROPES plaques respectively. This effect, once fully quantified should be accounted for in the Plaque SimulatorTM eye plaque brachytherapy planning system.

Delayed hypersensitivity reactions caused by iodixanol: An assessment of cross-reactivity in 22 patients

Delayed hypersensitivity reactions caused by iodixanol: An assessment of cross-reactivity in 22 patients

Role of Constituents of Optison in Optison-Mediated Gene Transfection Enhancement in Skeletal Muscle In Vivo

The mechanism by which Optison (an albumin-shelled, octafluoropropane gas-filled microbubble contrast agent; Amersham Health, Amersham, England) enhances gene transfection in skeletal muscle in vivo with or without ultrasound (US) is unclear. The possible mechanisms were investigated by experimenting with different constituents, both with and without US. Plasmid DNA (10 μg) encoding green fluorescent protein was mixed with Optison or its constituents dissolved in saline (in an equivalent concentration as in Optison) and injected into the tibialis anterior muscle of mice with or without adjunct US (1 MHz, 2 W/cm², 30 seconds, and 20% duty cycle). The efficiencies of green fluorescent protein transgene expression were determined under different experimental conditions: (1) plasmid plus saline as a negative control; (2) plasmid plus Optison as a positive control; (3) plasmid plus heat-treated Optison (without microbubbles); (4) plasmid plus human serum albumin; (5) plasmid plus N-acetyltryptophan; and (6) plasmid plus caprylic acid. Transfection efficiency was assessed by counting the maximum number of green fluorescent protein-positive fibers. Tissue damage was assessed by measuring the damaged area on serial sections. Heat-treated Optison with or without US and albumin with US showed similarly high levels of transgene expression as Optison in mouse muscle without substantially increased tissue damage. N-Acetyltryptophan and caprylic acid had no effect on the delivery of plasmid green fluorescent protein into mouse muscle but instead showed the potential to increase tissue damage. These data suggest that US and albumin separately potentiate transfection in this model. The combination of albumin and perfluoropropane is highly effective, which probably explains why Optison is so effective.

Acetylcysteine and non-ionic isosmolar contrast-induced nephropathy--a randomized controlled study

Intravenous administration of saline and non-ionic isosmolar contrast media significantly reduces the incidence of contrast-induced nephropathy, one of the most common causes of acute renal failure. Results with oral N-acetylcysteine are conflicting. The aim of our study was to evaluate the prophylactic role of N-acetylcysteine in patients with stable chronic renal failure undergoing coronary and/or peripheral angiography and/or angioplasty. We randomized 200 elective, consecutive patients (mean age 74.9 +/- 7.3 years; 65% male, 25% diabetics) with basal creatinine clearance <or=55 ml/min to receive oral N-acetylcysteine (600 mg bid the day before and the day of the procedure plus saline i.v. 0.9% 1 ml/kg/h 12-24 h before and 24 h after the procedure, n = 99) or placebo and saline at the same time intervals, n = 101. The contrast medium was non-ionic isosmolar (Iodixanol, Visipaque Amersham Health). Contrast-induced nephropathy was defined as an increase in serum creatinine >0.5 mg/dl or >25% within 3 days after the procedure. Serum creatinine was measured at baseline, 24, 48 and 72 h after the procedure. Contrast-induced nephropathy was 8/99 (8.1%) in the N-acetylcysteine group versus 6/101 (5.9%) in the placebo group, P = 0.6. No difference was noted in high-risk subgroups such as diabetics (4/25 versus 2/25 P = 0.4) and those with serum creatinine clearance <42.3 ml/min (5/54 versus 4/48; P = 0.9). In our experience, N-acetylcysteine did not prevent contrast-induced nephropathy in patients receiving isosmolar (iodixanol) contrast media and adequate hydration.

Case 146: Benign Multicystic Mesothelioma

History A 27-year-old gravida 1, para 1 woman who had a history of pelvic inflammatory disease presented to the emergency department with lower abdominal pain, nausea, vomiting, and chills. She began menstruating the night before presentation and reported an acute exacerbation of her chronic abdominal pain, which typically worsened with her menses. Her surgical history included one caesarean section and laparoscopic excision of a tubo-ovarian abscess. She was afebrile. Physical examination revealed mild diffuse abdominal tenderness and tenderness of the cervix. Laboratory findings revealed a white blood cell count of 17 000 cells per cubic millimeter. (A normal white blood cell count is between 4800 and 11 000 cells per cubic millimeter.) Ultrasonography (US) of the pelvis was performed. A computed tomographic (CT) examination of the abdomen and pelvis was subsequently performed after intravenous administration of 125 mL of iohexol (Omnipaque; Amersham Health, Princeton, NJ). We acquired 5-mm axial sections and performed 3-mm coronal reconstruction.

Fibrose systémique néphrogénique

To estimate the gain in signal-to-noise ratio (SNR) in first-pass contrast-enhanced (CE) abdominal magnetic resonance angiography (MRA) at 3.0 T compared with 1.5 T.Three protocols were simulated using six contrast agents: gadopentetate dimeglumine (Magnevist, Berlex, Wayne, NJ), gadoteridol (Prohance, Bracco, Princeton, NJ), gadobenate dimeglumine (Multihance, Bracco, Princeton, NJ), gadodiamide (Omniscan, Amersham Health, Princeton, NJ), gadoversetamide (Optimark, Mallinckrodt, St. Louis, MO), and gadofosveset trisodium (MS-325, EPIX Medical, Cambridge, MA). Contrast concentrations were calculated for five abdominal vessels. Based on these data, the gain in SNR during CE abdominal MRA at 3.0 T over 1.5 T was estimated.In these simulations, peak concentrations in all five target vessels were about 5 mM, 10 mM, and 0.7 mM for protocol 1, protocol 2, and protocol 3, respectively. A gain in SNR at 3 T over 1.5 T during CE abdominal MRA of at least 94% in all five target vessels could be achieved by applying protocol 1 or protocol 2, whereas protocol 3 provided a gain in SNR of 70%.Although five of the contrast agents studied fulfill the expectation of providing approximately twice the SNR at 3.0 T versus 1.5 T during CE abdominal MRA, MS-325 offers a gain in SNR of 70% only.

Development of a Dendritic Manganese-Enhanced Magnetic Resonance Imaging (MEMRI) Contrast Agent: Synthesis, Toxicity (in Vitro) and Relaxivity (in Vitro, in Vivo) Studies

A new dendritic manganese(II) chelate 1 has been evaluated by in vivo (relaxivity) and in vitro (toxicity and relaxivity) experiments as a manganese enhanced magnetic resonance imaging (MEMRI) contrast agent. Also, a comparison with its corresponding gadolinium(III) homologue 2 and the commercially available MEMRI agent MnDPDP (Teslascan, Amersham Health) was achieved in order to determine respectively the real influence of the paramagnetic ion in terms of toxicity and relaxivity for this precise treelike structure and the potential of 1 to be a favorable candidate for brain-targeting MRI. Complexes 1 and 2 displayed high hydrosolubility (0.1 M) and revealed no in vitro neuronal toxicity at concentrations as high as 1 mM. Considering manganese(II) complex 1, the in vivo nontoxicity at 20 mM (100% rats survival) is very likely due to a slow diffusion of the compound, meaning a controlled release of the paramagnetic ions. Finally, T(1) relaxivity of 4.2 mM(-1).s(-1) for 2 and T(2) relaxivity of 17.4 mM(-1).s(-1) for 1 at 4.7 T were measured and are higher than that of the commercial MRI contrast agents GdDTPA and MnDPDP, respectively.

Case 146

HomeRadiologyVol. 250, No. 2 PreviousNext Diagnosis PleaseFree AccessCase 146Phillip J. Koo, John S. WillsPhillip J. Koo, John S. WillsAuthor Affiliations1From the Department of Radiology, Pennsylvania Hospital, University of Pennsylvania Health System, 800 Spruce St, Philadelphia, PA 19107. Received July 13, 2007; revision requested September 10; revision received October 8; accepted December 17; final version accepted February 19, 2008.Address correspondence to P.J.K. (e-mail: [email protected]).Phillip J. KooJohn S. WillsPublished Online:Feb 1 2009https://doi.org/10.1148/radiol.2502071233MoreSectionsPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked InEmail HISTORYA 27-year-old gravida 1, para 1 woman who had a history of pelvic inflammatory disease presented to the emergency department with lower abdominal pain, nausea, vomiting, and chills. She began menstruating the night before presentation and reported an acute exacerbation of her chronic abdominal pain, which typically worsened with her menses. Her surgical history included one caesarean section and laparoscopic excision of a tubo-ovarian abscess. She was afebrile. Physical examination revealed mild diffuse abdominal tenderness and tenderness of the cervix. Laboratory findings revealed a white blood cell count of 17 000 cells per cubic millimeter. (A normal white blood cell count is between 4800 and 11 000 cells per cubic millimeter.)Ultrasonography (US) of the pelvis was performed (,Figs 1, ,2). A computed tomographic (CT) examination of the abdomen and pelvis was subsequently performed after intravenous administration of 125 mL of iohexol (Omnipaque; Amersham Health, Princeton, NJ). We acquired 5-mm axial sections and performed 3-mm coronal reconstruction (,Figs 3, ,4).Submit the most likely diagnosis to http://rsna.org/dxplease (use only for submission of diagnosis). Select the case from the Active Case List for which you are submitting a diagnosis. Only one case, one name, and one diagnosis per e-mail submission. Multiple diagnoses and multiple submissions will not be considered. Deadline: Midnight U.S. Central Time, April 10, 2009. Answer will appear in the June issue. Authors wishing to submit cases for Diagnosis Please should first write to the Editor to obtain approval for the case and further information.Figure 1: Sagittal transabdominal US image of the left adnexa.Figure 1:Download as PowerPointOpen in Image Viewer Figure 2: Axial transabdominal Doppler US image of the right lower quadrant of the abdomen.Figure 2:Download as PowerPointOpen in Image Viewer Figure 3: Oral (20 mL iohexol diluted with 430 mL of water) and intravenous contrast material–enhanced axial CT image of the pelvis.Figure 3:Download as PowerPointOpen in Image Viewer Figure 4: Oral and intravenous contrast-enhanced coronal CT image of the abdomen and pelvis.Figure 4:Download as PowerPointOpen in Image Viewer Authors stated no financial relationship to disclose.Article HistoryPublished in print: 2009 FiguresReferencesRelatedDetailsRecommended Articles Pelvic Inflammatory Disease: Multimodality Imaging Approach with Clinical-Pathologic CorrelationRadioGraphics2016Volume: 36Issue: 5pp. 1579-1596Case 268Radiology2019Volume: 291Issue: 1pp. 259-260Imaging of Peritoneal Dialysis Complications in ChildrenRadioGraphics2022Volume: 42Issue: 2pp. 559-578Interventional Radiology Placement and Management of Tunneled Peritoneal Dialysis Catheters: A Pictorial ReviewRadioGraphics2020Volume: 40Issue: 6pp. 1789-1806Imaging Evaluation of Fallopian Tubes and Related Disease: A Primer for RadiologistsRadioGraphics2020Volume: 40Issue: 5pp. 1473-1501See More RSNA Education Exhibits Pelvic Inflammatory Disease: Essentials of ImagingDigital Posters2018Danger in the Pelvis!!: A Case-based Review of Female Pelvic Emergencies on MDCTDigital Posters2020A Trainee’s Guide to Ovarian Emergencies in the EDDigital Posters2018 RSNA Case Collection Early pelvic inflammatory diseaseRSNA Case Collection2020Meckel's diverticulitisRSNA Case Collection2021Fitz-Hugh-Curtis syndromeRSNA Case Collection2021 Vol. 250, No. 2 Metrics Downloaded 323 times Altmetric Score

Non‐invasive prediction of the degree of liver fibrosis in patients with hepatitis C using an ultrasound contrast agent. A pilot study

It has been shown that the severity of hepatic fibrosis in patients with hepatitis C can be predicted non-invasively by measuring intrahepatic circulatory time (IHCT) using a microbubble agent with spectral Doppler analysis. The aim of this study was to assess whether this technique is reproducible using a third-generation microbubble agent and contrast harmonic imaging, which are becoming the standard ultrasound techniques in all radiology departments. Twenty-three untreated patients with hepatitis C, who had undergone a recent liver biopsy, were studied prospectively. Based on their histological fibrosis score, patients were divided into four groups (fibrosis levels 1-4). Contrast harmonic imaging was carried out after an intravenous bolus of a microbubble agent (Optison; Amersham Health, Milwaukee, WI, USA). IHCT was calculated by measuring the difference between the hepatic vein and hepatic artery microbubble arrival times. The IHCT was compared with the degree of fibrosis. Significant differences were shown between the groups for IHCT. There were significant differences between fibrosis levels 1 and 3 and between fibrosis levels 1 and 4. This study has shown that calculation of IHCT using a third-generation microbubble agent and contrast harmonic imaging can differentiate mild fibrosis from more severe degrees of fibrosis in patients with hepatitis C.

“Product Safety” Compromises Patient Safety (an Unjustified Black Box Warning on Ultrasound Contrast Agents by the Food and Drug Administration)

a In October 2007, the United States Food and Drug Adinistration (FDA)1 issued an alert requesting “black-box” arnings on the perflutren-based ultrasound contrast agents efinity (Bristol-Myers Squibb Medical Imaging, North illerica, Massachusetts) and Optison (Amersham Health, mersham, UK). Additionally, the FDA recommended that hese agents “be contraindicated in patients with unstable ardiopulmonary status, including patients with unstable ngina, acute myocardial infarction (MI), respiratory failre, or recent worsening congestive heart failure.” Accordng to the FDA’s Web site, there have been postmarketing eports of 10 deaths after the administration of Definity and after the administration of Optison. At least 6 of these ccurred 1 to 12 hours after dosing and were attributed to erious underlying conditions and/or other medications. our fatal cases, however, occurred 30 minutes after the dministration of Definity: 1 after a stress test, 2 in patients ith severe heart failure, and 1 in a ventilated patient with evere respiratory failure, sepsis, and multiple pulmonary mboli. These 4 deaths occurred over a 6-year period. Durng that period, 2 million doses were administered (Brisol-Myers Squibb Medical Imaging, personal communicaion). Thus, the fatal event rate was approximately 1 in 00,000. This rate is far less than the fatal event rate of a readmill exercise test (1 in 2,500)2 or a transesophageal chocardiogram (1 in 10,000).3 In fact, this extremely low vent rate testifies to the safety of these agents, considering hat they are frequently used in critically ill patients. It is lmost certain that the 4 fatal cases were consequences of evere underlying cardiovascular disease and were not aused by the contrast agent.4 According to the FDA’s Web site, the FDA “has the reponsibility for assuring the safety and efficacy of all regulated arketed medical products.” Product safety is not the same as atient safety. The FDA is concerned with whether a regulated rug or medical device has a potential adverse safety profile. hus, the FDA focuses on the term “product safety.” Patient afety lies within the domain of the physician-patient relationhip and is not the concern of the FDA. For example, consider he case of an elderly, debilitated patient with symptomatic, evere aortic stenosis. After extensive evaluation, her cardiolgist determines that although aortic valve replacement with an DA-approved bioprosthesis would relieve the aortic stenosis,

Concurrent activation of the somatosensory forebrain and deactivation of periaqueductal gray associated with diabetes-induced neuropathic pain

We combined behavioral testing with brain imaging using 99mTc-HMPAO (Amersham Health) to identify CNS structures reflecting alterations in pain perception in the streptozotocin (STZ) model of type I diabetes. We induced diabetic hyperglycemia (blood glucose > 300 mg/dl) by injecting male Sprague–Dawley rats with STZ (45 mg/kg i.p.). Four weeks after STZ-diabetic rats exhibited behaviors indicative of neuropathic pain (hypersensitivity thermal stimuli) and this hypersensitivity persisted for up to 6 weeks. Imaging data in STZ-diabetic rats revealed significant increases in the activation of brain regions involved in pain processing after 6 weeks duration of diabetes. These regions included secondary somatosensory cortex, ventrobasal thalamic nuclei and the basolateral amygdala. In contrast, the activation in habenular nuclei and the midbrain periaqueductal gray were markedly decreased in STZ rats. These data suggest that pain in diabetic neuropathy may be due in part to hyperactivity in somatosensory structures coupled with a concurrent deactivation of structures mediating antinociception.

Case 120: Ischemic Colitis Limited to the Cecum

A 75-year-old woman presented to the emergency department and reported new onset of diffuse abdominal cramps, nausea, fever, and chills. The patient had an extensive history of cardiac procedures, including placement of an aortic valve prosthesis and cardiac catheterization performed 10 days prior to the current admission. Her medical history was also notable for long-standing celiac sprue and acute appendicitis at age 13 that was treated with appendectomy. The patient denied recent foreign travel. Physical examination revealed mild right lower quadrant tenderness without signs of peritonitis and a fever of 100.4°F (38.0°C). White blood cell count, including absolute neutrophil count, was normal. Computed tomographic (CT) examination of the abdomen and pelvis was performed with only intravenous contrast material (100 mL of iohexol, Omnipaque 300; Amersham Health, Princeton, NJ) on day 1 and with both oral (15 g of diatrizoate sodium in 24 oz of water; Hypaque Sodium, Amersham Health) and intravenous contrast material on day 2.

Building on a 50‐year legacy of the MRC Cyclotron Unit: the Hammersmith radiochemistry pioneering journey

AbstractThe Medical Research Council Cyclotron Unit (MRC CU) situated at Hammersmith Hospital, London, is widely recognised for its pioneering developments in radiochemistry. The MRC CU became one of the largest and most comprehensive PET centres in the world. More recently, under the umbrella of a public/private partnership between the MRC and Amersham Health (now part of GE Healthcare) this centre has continued to advance PET research.This article reviews the 50‐year history of radiochemistry development and application for medical research at Hammersmith. Copyright © 2007 John Wiley &amp; Sons, Ltd.

Case 116: Lymphangioleiomyomatosis

A 49-year-old premenopausal woman presented with acute onset of lower abdominal pain. Physical examination revealed her abdomen was distended and nontender. Her white blood cell count and serum markers for ovarian cancer were normal (alpha-fetoprotein level, 1.6 microg/L; Ca-125 level, 15 U/mL; beta-human chorionic gonadotrophin level < 2 IU/mL). She had no important medical history; in particular, she had no history of malignancy. She denied having any chest symptoms; in particular, she denied experiencing chest pain, cough, or dyspnea. She had stopped smoking at the age of 40 years after having smoked for a total of 20 pack-years. A computed tomographic (CT) examination of the abdomen and pelvis was performed. Helical CT was performed with 150 mL of intravenous contrast material (iohexol, Omnipaque; Amersham Healthcare, Cork, Ireland) and 750 mL of oral contrast material (diatrizoate sodium, Hypaque; Amersham Health, Princeton, NJ). CT sections were 5 mm thick and were acquired from the top of the diaphragm through the ischial tuberosities with a rotation time of 13.5 seconds per rotation and use of a LightSpeed 16 CT scanner (GE Medical Systems, Milwaukee, Wis).

Gain in Signal-to-Noise for First-Pass Contrast-Enhanced Abdominal MR Angiography at 3 Tesla Over Standard 1.5 Tesla: Prediction with a Computer Model

To estimate the gain in signal-to-noise ratio (SNR) in first-pass contrast-enhanced (CE) abdominal magnetic resonance angiography (MRA) at 3.0 T compared with 1.5 T. Three protocols were simulated using six contrast agents: gadopentetate dimeglumine (Magnevist, Berlex, Wayne, NJ), gadoteridol (Prohance, Bracco, Princeton, NJ), gadobenate dimeglumine (Multihance, Bracco, Princeton, NJ), gadodiamide (Omniscan, Amersham Health, Princeton, NJ), gadoversetamide (Optimark, Mallinckrodt, St. Louis, MO), and gadofosveset trisodium (MS-325, EPIX Medical, Cambridge, MA). Contrast concentrations were calculated for five abdominal vessels. Based on these data, the gain in SNR during CE abdominal MRA at 3.0 T over 1.5 T was estimated. In these simulations, peak concentrations in all five target vessels were about 5 mM, 10 mM, and 0.7 mM for protocol 1, protocol 2, and protocol 3, respectively. A gain in SNR at 3 T over 1.5 T during CE abdominal MRA of at least 94% in all five target vessels could be achieved by applying protocol 1 or protocol 2, whereas protocol 3 provided a gain in SNR of 70%. Although five of the contrast agents studied fulfill the expectation of providing approximately twice the SNR at 3.0 T versus 1.5 T during CE abdominal MRA, MS-325 offers a gain in SNR of 70% only.

Initial Clinical Experience With Contrast-Enhanced Digital Breast Tomosynthesis

Contrast-enhanced digital mammography and digital breast tomosynthesis are two imaging techniques that attempt to increase malignant breast lesion conspicuity. The combination of these into a single technique, contrast-enhanced digital breast tomosynthesis (CE-DBT), could potentially integrate the strengths of both. The objectives of this study were to assess the clinical feasibility of CE-DBT as an adjunct to digital mammography, and to correlate lesion enhancement characteristics and morphology obtained with CE-DBT to digital mammography, ultrasound, and magnetic resonance (MR). CE-DBT (GE Senographe 2000D; Milwaukee, WI) was performed as a pilot study in an ongoing National Cancer Institute-funded grant (P01-CA85484) studying multimodality breast imaging. Thirteen patients with ACR BI-RADS category 4 or 5 breast lesions underwent imaging with digital mammography, ultrasound, MR, and CE-DBT. CE-DBT was performed at 49 kVp with a rhodium target and a 0.27-mm copper (Alfa Aesar, Ward Hill, MA) filter. Preinjection and postinjection DBT image sets were acquired in the medial lateral oblique projection with slight compression. Each image set consists of nine images acquired over a 50-degree arc and was obtained with a mean glandular x-ray dose comparable to two conventional mammographic views. Between the precontrast and postcontrast DBT image sets, a single bolus of iodinated contrast agent (1 ml/kg at 2 ml/s, Omnipaque-300; Amersham Health Inc., Princeton, NJ) was administered. Images were reconstructed using filtered-backprojection in 1-mm increments and transmitted to a clinical PACS workstation. Initial experience suggests that CE-DBT provides morphologic and vascular characteristics of breast lesions qualitatively concordant with that of digital mammography and MR. As an adjunct to digital mammography, CE-DBT may be a potential alternative tool for breast lesion morphologic and vascular characterization.

Bronchogenic Cyst with Extrinsic Pulmonary Vein and Left Atrial Compression Presenting as Exertional Dyspnea

A previously healthy 52-year-old male presented with a several week history of progressive exertional dyspnea. Physical examination and electrocardiogram were unremarkable. A transthoracic echocardiogram (TTE) was performed (Fig. 1). Initially it was thought that a membrane was within a large left atrium (LA). To further delineate the LA and its anatomy, peripheral injection of sonicated contrast (Optison, Amersham Health, Inc., Princeton, NJ) was performed (Fig. 2). A “contrast-free” cystic appearing structure became readily apparent. Computed tomography (CT) of the chest likewise demonstrated a cystic structure adjacent to the LA (Fig. 3). Transesophageal echocardiography (TEE) was then performed. In addition to the cystic mass (Fig. 4), the flow velocity profile in the left upper pulmonary vein (LUPV) was consistent with extrinsic pulmonary vein compression (Fig. 5). The patient subsequently underwent surgical resection of the mass, and had an uneventful recovery. The chief complaint of progressive exertional dyspnea resolved. Histopathology identified ciliated stratified epithelium, consistent with a bronchogenic cyst. A bronchogenic cyst is a congenital lesion that is a remnant from abnormal budding of the embryonic foregut. These cysts are usually single,

Acoustic Techniques for Assessing the Optison Destruction Threshold

The purpose of this study was to identify the pressure threshold for the destruction of Optison (octafluoropropane contrast agent; Amersham Health, Princeton, NJ) using a laboratory-assembled 3.5-MHz pulsed ultrasound system and a clinical diagnostic ultrasound scanner. A 3.5-MHz focused transducer and a linear array with a center frequency of 6.9 MHz were positioned confocally and at 90 degrees to each other in a tank of deionized water. Suspensions of Optison (5-8x10(4) microbubbles/mL) were insonated with 2-cycle pulses from the 3.5-MHz transducer (peak rarefactional pressure, or Pr, from 0.0, or inactive, to 0.6 MPa) while being interrogated with fundamental B-mode imaging pulses (mechanical index, or MI,=0.04). Scattering received by the 3.5-MHz transducer or the linear array was quantified as mean backscattered intensity or mean digital intensity, respectively, and fit with exponential decay functions (Ae-kt+N, where A+N was the amplitude at time 0; N, background echogenicity; and k, decay constant). By analyzing the decay constants statistically, a pressure threshold for Optison destruction due to acoustically driven diffusion was identified. The decay constants determined from quantified 3.5-MHz radio frequency data and B-mode images were in good agreement. The peak rarefactional pressure threshold for Optison destruction due to acoustically driven diffusion at 3.5 MHz was 0.15 MPa (MI=0.08). Furthermore, the rate of Optison destruction increased with increasing 3.5-MHz exposure pressure output. Optison destruction was quantified with a laboratory-assembled 3.5-MHz ultrasound system and a clinical diagnostic ultrasound scanner. The pressure threshold for acoustically driven diffusion was identified, and 3 distinct mechanisms of ultrasound contrast agent destruction were observed with acoustic techniques.