Waxing and Waning Presentation of Isolated Cardiac Sarcoidosis on Sequential 18F-FDG PET Examinations.

We describe the case of a patient who had suspected myocardial ischemia, showed normal findings on multiple perfusion scans, and showed isolated cardiac sarcoidosis on 18F-FDG-PET. Also discussed are the diagnosis and the monitoring of disease response using imaging follow-up.

Image Quality and Patient-Specific Organ Doses in Stone Protocol CT: A Comparison of Traditional CT to Low Dose CT with Iterative Reconstruction.

OBJECTIVE: To compare organ specific radiation dose and image quality in kidney stone patients scanned with standard CT reconstructed with filtered back projection (FBP-CT) to those scanned with low dose CT reconstructed with iterative techniques (IR-CT). MATERIALS AND METHODS: Over a one-year study period, adult kidney stone patients were retrospectively netted to capture the use of noncontrasted, stone protocol CT in one of six institutional scanners (four FBP and two IR). To limit potential CT-unit use bias, scans were included only from days when all six scanners were functioning. Organ dose was calculated using volumetric CT dose index and patient effective body diameter through validated conversion equations derived from previous cadaveric, dosimetry studies. Board-certified radiologists, blinded to CT algorithm type, assessed stone characteristics, study noise, and image quality of both techniques. RESULTS: FBP-CT (n=250) and IR-CT (n=90) groups were similar in regard to gender, race, body mass index (mean BMI = 30.3), and stone burden detected (mean size 5.4 ± 1.2 mm). Mean organ-specific dose (OSD) was 54-62% lower across all organs for IR-CT compared to FBP-CT with particularly reduced doses (up to 4.6-fold) noted in patients with normal BMI range. No differences were noted in radiological assessment of image quality or noise between the cohorts, and intrarater agreement was highly correlated for noise (AC2=0.873) and quality (AC2=0.874) between blinded radiologists. CONCLUSIONS: Image quality and stone burden assessment were maintained between standard FBP and low dose IR groups, but IR-CT decreased mean OSD by 50%. Both urologists and radiologists should advocate for low dose CT, utilizing reconstructive protocols like IR, to reduce radiation exposure in their stone formers who undergo multiple CTs.

Coronary artery bypass graft pseudoaneurysm from saphenous vein graft stent fracture.

Saphenous venous graft (SVG) pseudoaneurysms are a rare complication of coronary artery bypass grafting (CABG). An 85-year-old man with CABG and a distal SVG stent presented with dyspnea. Chest computed tomography (CT) revealed a large partially thrombosed pseudoaneurysm at the distal SVG with stent fracture. Endoluminal exclusion of the distal SVG pseudoaneurysm using a covered stent was performed. Follow-up chest CT and angiography showed persistent pseudoaneurysm filling and enlargement. The SVG proximal to the pseudoaneurysm was embolized with coils to reduce rupture risk. Following embolization, the patient's left ventricular ejection fraction was moderately depressed but the patient remained stable and was discharged. .

Fluorodeoxyglucose-positron-emission tomography/computed tomography imaging for adrenal masses in patients with lung cancer: review and diagnostic algorithm.

BACKGROUND AND PURPOSE: Positron-emission tomography/computed tomography (PET/CT) with fluorine-18 fluorodeoxyglucose (FDG) is used as first-line staging for patients with newly diagnosed non-small cell lung cancer (NSCLC). Our purpose was to review the accuracy of FDG-PET/CT to predict adrenal gland metastasis, explain the causes for false-positive PET, and provide a diagnostic algorithm. PATIENTS AND METHODS: Two patients with incidentally discovered lung masses were found to have hypermetabolic adrenal activity by FDG-PET/CT with maximal standard uptake value (SUV) of 4.5 and 6.5. A MEDLINE search was performed on the topic of FDG-PET/CT, adrenal gland metastasis, and NSCLC. Literature was reviewed with regard to diagnosis, accuracy, outcomes, and alternative imaging or diagnostic strategies. RESULTS: Both patients underwent transabdominal laparoscopic adrenalectomy and were found to have nodular hyperplasia without evidence of adrenal tumor. A total of seven articles containing 343 patients were identified as having pertinent oncologic information for NSCLC patients with adrenal lesions. Sensitivity and specificity of PET/CT for distant metastasis was 94% and 85%, respectively, but only 13% (44/343) of these patients had histologically confirmed adrenal diagnoses. Based on this, a diagnostic algorithm was created to aid in decision making. CONCLUSIONS: Although PET/CT has high sensitivity and specificity for adrenal metastasis in the setting of NSCLC, adrenal biopsy or other secondary imaging should be considered to confirm the finding. Adrenalectomy in lieu of biopsy may have both diagnostic and therapeutic benefit in cases where the adrenal mass is ≥10 mm with high PET maximum SUV (≥3.1) and SUV ratios (>2.5), where washout CT or chemical shift MRI is positive, or where percutaneous biopsy is deemed too difficult or unsafe.

Immediate computed tomography coronary angiography versus delayed outpatient stress testing for detecting coronary artery disease in emergency department patients with chest pain.

Noninvasive testing for coronary artery disease (CAD) is warranted for symptomatic patients with intermediate pretest likelihood of CAD. Accomplishing testing in an emergency department (ED) environment is challenging. We compared two strategies of CAD testing in ED patients: immediate computed tomography coronary angiography (CTCA) versus delayed outpatient stress testing. We conducted a historical control cohort study comparing symptomatic ED patients without an acute coronary syndrome who warranted noninvasive CAD testing. Two cohorts (50 patients each) were defined by CAD testing strategy, immediate CTCA versus delayed stress testing. Outcomes were duration of ED stay, detection of CAD, and 3-month rates of readmission, myocardial infarction, (MI) or death. Median duration of stay was 417.5 minutes (interquartile range [IQR] 359.0-581.0) in the CT cohort and 400.0 minutes (IQR 338.0-471.0) in the control cohort (P = 0.53). CAD was detected in 14 CT cohort patients versus 1 in control (P = 0.0004), due to low follow-up in the control cohort (18 of 50, 36%). Obstructive CAD was diagnosed in 6 CT cohort patients versus 1 in control (P = 0.11). During 3 months of follow-up, four patients in each cohort were reevaluated in the ED for chest pain; no patients suffered MI or death. A strategy of immediate CTCA is superior to a delayed stress testing strategy for detecting CAD in ED patients with chest pain and prompting appropriate referrals for further management. Delayed stress testing was primarily ineffective due to low follow-up. Immediate CTCA can be used safely without altering the ED duration of stay.

Responsible use of computed tomography in the evaluation of coronary artery disease and chest pain.

Many options are available to clinicians for the noninvasive evaluation of the cardiovascular system and patient concerns about chest discomfort. Cardiac computed tomography (CT) is a rapidly advancing field of noninvasive imaging. Computed tomography incorporates coronary artery calcium scoring, coronary angiography, ventricular functional analysis, and information about noncardiac thoracic anatomy. We searched the PubMed database and Google from inception to September 2009 for resources on the accuracy, risk, and predictive capacity of coronary artery calcium scoring and CT coronary angiography and have reviewed them herein. Cardiac CT provides diagnostic information comparable to echocardiography, nuclear myocardial perfusion imaging, positron emission tomography, and magnetic resonance imaging. A cardiac CT study can be completed in minutes. In patients with a nondiagnostic stress test result, cardiac CT can preclude the need for invasive angiography. Prognostic information portends excellent outcomes in patients with normal study results. Use of cardiac CT can reduce health care costs and length of emergency department stays for patients with chest pain. Cardiac CT examination provides clinically relevant information at a radiation dose similar to well-established technologies, such as nuclear myocardial perfusion imaging. Advances in technique can reduce radiation dose by 90%. With appropriate patient selection, cardiac CT can accurately diagnose heart disease, markedly decrease health care costs, and reliably predict clinical outcomes.