Delayed gastric emptying and improvement with domperidone in a patient with anorexia nervosa.

A woman with anorexia nervosa who displayed severe bloating after eating was treated with domperidone, a novel compound with prokinetic properties. Both subjective ratings of satiety and assessment of gastric emptying documented improvement.

Gallium-67 scanning in the diagnosis of postoperative sternal osteomyelitis: concise communication.

Sternal osteomyelitis is an uncommon but serious complication of the median sternotomy incision. Definite diagnosis is clinically difficult and radionuclide scanning is of uncertain value in the early postoperative period. We conducted a prospective blind study of gallium scanning in the early period after cardiac surgery and reviewed clinically diagnosed cases that also had scans. Clinical status and scan interpretation were each independently assessed by three raters. Thirty-eight scans included six true positives, five true negatives (no sternotomy) and 27 post-sternotomy, clinically uninfected patients. Using categories of high, medium, and low for scan interpretation, the radiologic assessors agreed 90% of the time. Normal postoperative Ga-67 uptake could usually be differentiated from uptake by an infected sternum. The test had a sensitivity of 83% and specificity 96%. If the clinical (pretest) likelihood of sternal osteomyelitis is 30%, then the gallium scan will have a 90% positive predictive value and a 93% negative predictive value. This study of observer variation and validity indicates that Ga-67 scanning may be useful in confirming the diagnosis of poststernotomy sternal osteomyelitis.

Clinical evaluation of 360 degrees and 180 degrees data sampling techniques for transaxial SPECT thallium-201 myocardial perfusion imaging.

The most serious controversy regarding the application of transaxial SPECT technology to 201Tl myocardial perfusion imaging is the choice between 360 degrees compared with 180 degrees data sampling techniques. The present study utilized the original 360 degrees sampled raw data of 25 patients who had both SPECT 201Tl myocardial perfusion imaging and coronary angio/ventriculography for back projection reprocessing to accomplish the 360 degrees/180 degrees comparison. The results show a high incidence, 36% (9/25), of false-positive segmental perfusion abnormality and a high incidence, 24% (6/25), of moderate to severe degree of image distortion with the 180 degrees data sampled reconstructed images. These were not observed in the 360 degrees data sampled reconstructed images. The above findings confirmed our previous preliminary conclusion that even though the 180 degrees data sampling technique has the advantage of providing improved image contrast and reduction in acquisition time it is not a reliable technique and should be abandoned. The 360 degrees data sampling is the technique of choice for transaxial SPECT 201Tl myocardial perfusion imaging.

Vasodilator therapy in refractory congestive heart failure: a comparative analysis of hemodynamic and noninvasive studies.

The response to vasodilator therapy was assessed in 12 patients with chronic severe congestive heart failure refractory to conventional treatment. Cardiac output and intraarterial and pulmonary capillary wedge pressures were recorded continuously to assess the hemodynamic response to the vasodilators used. Control and post-treatment M mode echocardiograms and radionuclide angiograms were obtained to assess the change in left ventricular size and ejection fraction concurrent with the hemodynamic improvement. Despite a 33 percent decrease in pulmonary capillary wedge pressure (p less than 0.001) and a 35 percent increase in cardiac index (p less than 0.001), no significant change occurred in left ventricular end-diastolic or end-systolic chamber size on echocardiography or in ejection fraction measured with radionuclide angiography. In this study M mode echocardiography and radionuclide angiography were of no value in monitoring the actual hemodynamic response to vasodilator therapy in this group of patients with a left ventricular ejection fraction of less than 30 percent.

Abdominal fat distribution in pre- and postmenopausal women: The impact of physical activity, age, and menopausal status.

Age-related increases in total body fat have been reported, but the impact of menopause on abdominal fat distribution is still unclear. The purpose of this study was to determine the impact of menopausal status on abdominal fat distribution using magnetic resonance imaging (MRI). In addition, we investigated the influence of abdominal fat distribution on blood lipid profiles and leptin concentrations. Twenty-three premenopausal (PRE), 27 postmenopausal (POST), and 28 postmenopausal women on estrogen replacement therapy (ERT) had measurements of regional abdominal fat, blood lipids, and serum leptin concentrations. The women were matched for body mass index (BMI) and total body fat mass. Age and menopausal status were not found to be significant predictors of total abdominal fat, visceral fat, or subcutaneous fat, while physical activity was a significant predictor (P <.01) for total abdominal fat (R(2) =.16), visceral fat (R(2) =.32) and percent visceral fat (R(2) =.25). There was a trend for a greater visceral fat content in the POST women compared with the PRE women (2,495.0 +/- 228.4 v 1,770.4 +/- 240.8 cm(2), respectively, P =.06). The percent visceral abdominal fat was significantly lower (P <.05) in the premenopausal women than in either postmenopausal group (PRE, 23.2% +/- 1.7%; POST, 28.9% +/- 1.8%; ERT, 28.9% +/- 1.6%). Menopausal status and age did not influence any of the blood lipid values. Abdominal fat distribution was a significant predictor of cholesterol concentrations and the cholesterol/high-density lipoprotein-cholesterol (HDL-C) ratio, but only accounted for approximately 15% of the variability in these levels. Total body fat and physical activity accounted for 47% of the variability in leptin concentrations, while abdominal fat distribution, age, and menopausal status were not significant predictors. In conclusion, in early postmenopausal women, the level of physical activity accounts for the variability in abdominal fat distribution observed, while menopausal status and age do not play a significant role. ERT was not associated with additional benefits in abdominal fat distribution compared with postmenopausal women not on ERT or in the blood lipid profile in these women.

Magnetic resonance imaging of musculoskeletal infections.

In summary, MRI has a high sensitivity for the detection of inflammatory disease involving the musculoskeletal system. Because of the usual anatomic pattern of involvement in the vertebral column, there is also a high specificity. In the appendicular skeleton and pelvis, it is unclear whether MRI can add to the sensitivity and specificity of radionuclide studies in uncomplicated cases of acute infection. However, it can be performed more rapidly and provides greater anatomic detail and delineation of the extent of marrow involvement than radionuclide studies. MRI can be used in both acute and chronic osteomyelitis to guide a diagnostic interventional test to the appropriate site. It is capable of excluding involvement of the medullary canal, and it is better than radionuclide studies for differentiating soft tissue infection with periostitis from osteomyelitis. It has only a limited role in the immediate postoperative period, and in the presence of metallic implants, an indium-labeled leukocyte scan may be more appropriate. Finally, it must be remembered that the current data base of MRI is small and that further refinement of its role in the evaluation of inflammatory processes will be forthcoming.

Invasive aspergillosis diagnosed by fine-needle aspiration of the thyroid gland.

Invasive aspergillosis has been increasingly recognized as causing significant morbidity and mortality in immunocompromised patients but has never been diagnosed by fine-needle thyroid aspiration. A 24-year-old female with systemic lupus erythematosus presented with cough, shortness of breath, and fever of unknown origin unresponsive to broad-spectrum antibiotics. History and physical examination failed to indicate a source of infection. An 111In white blood cell scan showed thyroid localization. Physical examination revealed a multinodular goiter with a left dominant nodule. Fine-needle aspiration biopsy of a thyroid nodule revealed branching hyphae suggestive of Aspergillus sp. Despite immediate and aggressive treatment with amphotericin B and fluconazole, the patient died of overwhelming infection.

An EM algorithm for estimating SPECT emission and transmission parameters from emissions data only.

A maximum-likelihood (ML) expectation-maximization (EM) algorithm (called EM-IntraSPECT) is presented for simultaneously estimating single photon emission computed tomography (SPECT) emission and attenuation parameters from emission data alone. The algorithm uses the activity within the patient as transmission tomography sources, with which attenuation coefficients can be estimated. For this initial study, EM-IntraSPECT was tested on computer-simulated attenuation and emission maps representing a simplified human thorax as well as on SPECT data obtained from a physical phantom. Two evaluations were performed. First, to corroborate the idea of reconstructing attenuation parameters from emission data, attenuation parameters (mu) were estimated with the emission intensities (lambda) fixed at their true values. Accurate reconstructions of attenuation parameters were obtained. Second, emission parameters lambda and attenuation parameters mu were simultaneously estimated from the emission data alone. In this case there was crosstalk between estimates of lambda and mu and final estimates of lambda and mu depended on initial values. Estimates degraded significantly as the support extended out farther from the body, and an explanation for this is proposed. In the EM-IntraSPECT reconstructed attenuation images, the lungs, spine, and soft tissue were readily distinguished and had approximately correct shapes and sizes. As compared with standard EM reconstruction assuming a fix uniform attenuation map, EM-IntraSPECT provided more uniform estimates of cardiac activity in the physical phantom study and in the simulation study with tight support, but less uniform estimates with a broad support. The new EM algorithm derived here has additional applications, including reconstructing emission and transmission projection data under a unified statistical model.

Allograft reconstruction of the acetabulum during revision total hip arthroplasty. Clinical, radiographic, and scintigraphic assessment of the results.

In twenty-one hips of twenty-one patients, the acetabulum was reconstructed using allografts during revision of a total hip arthroplasty. The patients' average age at the time of revision was 64.3 years (range, nineteen to eighty-six years). At an average follow-up of 3.5 years (range, two to five years), three patients had died of causes unrelated to the hip reconstruction, and one had been lost to follow-up. In the other seventeen, the average Harris hip rating was 89 points (range, seventy to 100 points) at follow-up. In one patient the allograft collapsed, so that revision was required. Two patients had asymptomatic progressive radiolucencies at the cement-bone interface of the reconstructed acetabulum, and another had a 1.5-millimeter-wide lucency at the interface of the donor and recipient bone but was asymptomatic, and there had been no change in the position of the cemented acetabular component since operation. The remaining grafts appeared to be incorporated securely, as determined by radiographic examination. Three-dimensional computerized tomographic radioisotopic bone scans showed uniform uptake, consistent with revascularization and new-bone formation, in all grafts. There was no radiographic evidence of focal avascularity and there were no infections. Femoral-head bone allografts appear to provide a useful technique for the reconstruction of a severely deficient acetabulum during revision total hip arthroplasty.

Magnetic resonance imaging of a third trimester abdominal pregnancy.

Abdominal pregnancies are rare, representing 1% of all ectopic pregnancies. Early and accurate diagnosis is essential in order to avoid the serious complications associated with the condition, including catastrophic hemorrhage secondary to placental separation. The clinical presentation of abdominal pregnancy is extremely variable and physical examination by itself may be insufficient for diagnosis. Ultrasound (US) is currently the imaging method of choice for establishing gestational location, but sonographic interpretation may be difficult due to gas within the gastrointestinal tract and distorted pelvic anatomy. The use of magnetic resonance imaging (MRI) in obstetric diagnosis, including abdominal pregnancy, has been described. We report a case of an abdominal pregnancy of 32 wk gestation diagnosed by MRI.

Quantitation of abnormal 67Ga uptake in pulmonary interstitial vascular disease--a new test to detect diffuse lung disease.

Gallium 67 has been used as a modality to diagnose and follow the clinical course of diseases such as tumors, infections, inflammatory disorders, and interstitial lung disease. It has been appreciated, however, that mild to moderate changes in scan activity, when these disorders are followed over time, are less than optimal. SPECT (single-photon emission computed tomography) scanning is a new technique designed to obviate this problem. SPECT scanning utilizes computer acquisition to provide three-dimensional scanning and the additional benefit of colorization to aid in discerning differences of uptake. SPECT scanning was performed on 22 patients with interstitial lung disease of various etiologies. Additionally, 7 patients had follow-up SPECT scanning to determine their response to treatment. Two patients are presented as examples.

Radionuclide assessment of the natural heart ejection fraction before and after LVAD implantation.

Complete pressure unloading of the ventricles can preserve ischemically damaged myocardium. Most clinical left heart assist device (LVAD) systems used after ischemic injury of the heart apply atrial cannulation which does not ensure pressure unloading. In order to assess the effect of the implantation of an intracorporeal LVAD on the function of the natural heart, we determined the ejection fraction (EF) in four male Holstein calves (90-105 kg) before and after insertion of a Cleveland Clinic pneumatic LVAD. A gated blood pool scan was obtained with a gamma camera after injection of 40 mCi Tc-labelled albumin. The animals were restrained in a sling to avoid movement artifacts. All animals showed a drop of 65 +/- 12% to 42 +/- 14% EF in the first postoperative (p.o.) week. Left ventricular output did not maintain sufficient blood pressure as assessed by pump-off tests. Systolic blood pressure dropped from 122 +/- 6.5 mm Hg to 81 +/- 6 mm Hg without pump support on the morning of the first p.o. day. Apical coring and possible restrained heart movement by the implanted LVAD may lead to impaired myocardial function that renders the individual LVAD dependent until adaptative corrections take place.

The "hot" patella.

Increased patellar uptake on bone scans is seen quite commonly but the possible or probable etiologies of this finding have not been previously well described. A review of 100 consecutive bone scans showed that the incidence of bilateral "hot" patellae is 15%. Identified etiologies include osteoarthritic degenerative disease (35%), fracture, possible metastatic disease, bursitis, Paget's disease, and osteomyelitis. The value of careful history, physical examination, and radiographs is stressed.

Generation of parametric images during routine Tc-99m PYP inhalation/Tc-99m MAA perfusion lung scintigraphy. Technical note.

A simple technique is described for generating ventilation/perfusion ratio and perfusion/ventilation ratio images from the posterior Tc-99m PYP aerosol inhalation and Tc-99m MAA perfusion images obtained during routine lung scintigraphy. These images highlight areas of ventilation/perfusion incongruence--mismatch or reverse mismatch--that may sometimes be difficult to detect on conventional images.

Computerized method for nonrigid MR-to-PET breast-image registration.

We have developed and tested a new simple computerized finite element method (FEM) approach to MR-to-PET nonrigid breast-image registration. The method requires five-nine fiducial skin markers (FSMs) visible in MRI and PET that need to be located in the same spots on the breast and two on the flanks during both scans. Patients need to be similarly positioned prone during MRI and PET scans. This is accomplished by means of a low gamma-ray attenuation breast coil replica used as the breast support during the PET scan. We demonstrate that, under such conditions, the observed FSM displacement vectors between MR and PET images, distributed piecewise linearly over the breast volume, produce a deformed FEM mesh that reasonably approximates nonrigid deformation of the breast tissue between the MRI and PET scans. This method, which does not require a biomechanical breast tissue model, is robust and fast. Contrary to other approaches utilizing voxel intensity-based similarity measures or surface matching, our method works for matching MR with pure molecular images (i.e. PET or SPECT only). Our method does not require a good initialization and would not be trapped by local minima during registration process. All processing including FSMs detection and matching, and mesh generation can be fully automated. We tested our method on MR and PET breast images acquired for 15 subjects. The procedure yielded good quality images with an average target registration error below 4mm (i.e. well below PET spatial resolution of 6-7 mm). Based on the results obtained for 15 subjects studied to date, we conclude that this is a very fast and a well-performing method for MR-to-PET breast-image nonrigid registration. Therefore, it is a promising approach in clinical practice. This method can be easily applied to nonrigid registration of MRI or CT of any type of soft-tissue images to their molecular counterparts such as obtained using PET and SPECT.

Liposuction fat-fillant implant for breast augmentation and reconstruction.

The perfect breast implant fillant material would have higher viscosity than water and would be autologous and harmless. We describe the confinement of liposuction fat in implants using the Lipovacutainer during a routine liposuction procedure. This collected fat is prepared inside the Lipovacutainer and is reinjected through a Lipomedia filling cannula into a leaf valve implant as the fillant in place of saline. The implants are used for bilateral augmentation mammoplasty and breast reconstruction procedures. Our six clinical cases have been monitored closely using mammography and MRI. These cases showed slow liquefaction without interference with mammography studies. We obtained excellent overall body contours. All complications were correctable and non-life-threatening and there was no capsule formation.