Obscured bone metastases after administration of hematopoietic factor on FDG-PET.

We describe interesting imaging features on a FDG-PET scan in a patient with bony metastases from a rare tumor. The lesions were obscured by intense bone marrow activity after the administration of hematopoietic factor at the time of diagnosis. Correlative MRI, CT scan, and pathology findings have also been illustrated.

Effects of six-month afterload reduction therapy with hydralazine in chronic aortic regurgitation.

Seventeen patients with chronic asymptomatic aortic regurgitation (AR) were studied to determine whether 6 months of hydralazine therapy can reduce the severity of AR or reverse left ventricular (LV) enlargement and hypertrophy. Echocardiography, radionuclide angiography at rest and during exercise, and maximal treadmill exercise with respiratory gas analysis were performed at intake and after a 6-month double-blind treatment period. After dose titration with hydralazine, patients were randomized to their maximal tolerated hydralazine dose or to placebo.

Bone imaging appearance of Pelligrini Stieda syndrome.

In a bone scan performed on a patient with Pelligrini Stieda syndrome of the left knee, abnormal tracer uptake was noted. Pelligrini Stieda should be added to the list of benign abnormalities on bone images.

Effects of age on ventricular performance during graded supine exercise.

To assess the effects of age on ventricular performance, graded supine exercise tests with equilibrium radionuclide ventriculography were performed in six normal subjects of mean age 37 +/- 4 years and in eight normal subjects with a mean age of 59 +/- 2 years. At a standard submaximal work load, older subjects had a similar heart rate (older: 126 +/- 10, younger: 128 +/- 5 bpm) and systolic blood pressure responses (older: 198 +/- 24, younger: 202 +/- 24 mm Hg). Cardiac output counts increased appropriately in both groups during submaximal exercise.

A false-positive indium-111 labeled leukocyte scintigram in a patient with a painful hip prosthesis.

A Tronzo hip prosthesis is designed to elicit an inflammatory reaction in order to promote prosthesis stability. A three-phased bone scan and Ga-67 imaging in conjunction with physical examination and laboratory findings failed to demonstrate evidence for osteomyelitis in a patient with a painful hip prosthesis, in whom images obtained with In-111-labeled leukocytes were positive. This observation demonstrated that the interpretation of the latter technique in demonstrating inflammation can cause a false impression of an infectious process.

Visualization of the uterus on evaluation of transplanted kidneys.

A vascular blush was noted in the pelvis during flow studies in two women with kidney transplants. The vascular structure was noted to be due to the uterus. In one patient, the activity in the area of the uterus could have been mistaken for excretion of agent into the bladder.

Sources of variability in quantitative thallium analysis.

Nineteen patients undergoing exercise thallium scanning had two separate redistribution 40 degree LAO acquisitions obtained; the gamma camera was repositioned between the views. Data were analyzed by generating 60-point circumferential profile curves for each of the 38 images and the variability of individual points and 18 degrees and 36 degrees segments was determined. Intraobserver variability, assessed by reanalyzing the scans one week later, was approximately 5.

Osteomalacia. An imposter of osseous metastasis.

A case of osteomalacia with multiple asymmetrically distributed pseudofractures (Looser's zones) simulating metastases is presented. Radiographic correlation is essential to increase specificity and avoid misinterpretation.

Quantitative analysis of liver function in percutaneous transhepatic biliary drainage patients.

The diagnostic usefulness of Tc-99m DISIDA cholescintigraphy as a predictor of eventual catheter and hepatic function in patients who have undergone percutaneous transhepatic biliary drainage (PTBD) for extrahepatic biliary obstruction was evaluated. Twenty-nine cholescintigrams were performed in 14 patients. The examinations were divided into two groups: Group A (N = 17), in which the patient's clinical status deteriorated within two to three days post-PTBD, and Group B (N = 12), in which the patients did well clinically post-PTBD.

Early changes in thallium distribution. Effect on quantitative analysis.

Thirty-two patients with coronary artery disease and an abnormality on an initial anterior view thallium scan had repeat images obtained after delays of 30 and 240 minutes. Scans were analyzed by quantitative criteria. Comparison of the initial stress study with the 30-minute redistribution scan showed no significant change in 11 patients, defects becoming smaller in 13 patients, and defects becoming larger in eight patients.

Accuracy of left ventricular ejection fraction using the nuclear stethoscope in left ventricular aneurysm.

Although the nuclear stethoscope, a nonimaging probe, accurately determines left ventricular (LV) ejection fraction (EF), its reliability in patients with LV aneurysm has not been established. Accordingly, LVEF was determined using the nuclear stethoscope and compared with that determined by equilibrium gated blood pool scanning in 29 patients, 1 studied on 2 separate occasions, for a total of 30 patient studies. Patient studies were separated into 2 groups.

Multiple-hospital survey of ejection-fraction variability using a cardiac phantom.

A dynamic cardiac phantom was used to provide identical input data at 11 different nuclear medicine laboratories throughout the Philadelphia area, and the variability in the resulting calculations of ejection fraction (EF) was assessed. The variability observed between different operators using the same computer system averaged 3 EF units, which was similar to that between different observers using different types of computers. In the range of low ejection fractions, however, there was a suggestion that EFs calculated with an MDS computer were slightly lower than those from a DEC computer.