Transhiatal esophagectomy with primary anastomosis to the stomach (gastric pull-up) is an attractive surgical alternative to colic interposition in patients with cancer of the esophagus and hypopharynx. However, the lack of intrinsic gastric peristalsis and complaints by patients of postprandial regurgitation prompted us to measure the effect of body posture on the rates of gastric emptying in these patients. The rates of solid and liquid gastric emptying were measured in 14 patients who had undergone gastric interposition for esophageal and hypopharyngeal carcinoma. Rates of emptying were measured in both the supine and upright position using a dual-isotope radiolabeling technique. In these patients, the rate of gastric emptying of both solids and liquids was significantly slower in the supine position than in the upright position. Emptying in supine patients was also prolonged when compared with supine normal volunteers. Conversely, the upright rate of solid and liquid emptying in the patients was accelerated when compared with published values for upright normal volunteers. We conclude that gastric emptying after gastric interposition is dependent on upright posture after meals.

A commercial three-detector single-photon emission computed tomography (SPECT) system that enables simultaneous acquisition of transmission and emission data without increasing patient scanning time has been designed and manufactured. This system produces a reconstructed attenuation coefficient distribution that can be used to correct for photon attenuation in the emission reconstruction. The three detectors with fan-beam collimators are mounted to the gantry in a triangular arrangement. A transmission line source assembly was mounted at the focal line of one of the detectors and controlled to move in synchrony with the opposing fan-beam collimator. Data from transmission and emission sources at different energies were acquired in one detector, while the other two simultaneously acquired emission data. A transmission source of /sup 153/Gd was used with /sup 99m/Tc-labeled radiopharmaceuticals, and /sup 57/Co was used with /sup 201/Tl. Algorithms were developed to subtract crosstalk between transmission and emission energy windows in all three detectors. A transmission maximum-likelihood iterative algorithm was used to reconstruct the attenuation distribution, which was used in combination with an iterative maximum-likelihood expectation-maximization algorithm to compensate for the attenuation of the projection of the emission distribution. The results in phantom studies displayed greater uniformity of activity with attenuation-corrected reconstruction. This was demonstrated visually and quantitatively by using anterior-to-inferior ratios close to one and low spatial %rms error as a measure of improved uniformity.

31:1844-1846. 20. Laven DL, Shaw SM. Detection of drug interactions involving radiopharmaceuticals: a professional responsi bility of the clinical pharmacist. J Pharm Prac 1989;2: 287-298. 21. Larar GN, Janicek MJ, Kaplan WD. Gallium-67 scintigraphy after bone marrow harvest. Significance of sacroiliac asymmetry in the lymphoma patient. Clin NucAMed 1993;18:126-129. 22. Thomas SR, Gelfand MJ, et al. Radiation absorbed-dose estimates for the liver, spleen and metaphyseal growth complexes in children undergoing gallium-67-citrate scanning. Radiologi' 1983; 146:817-820. 23. Feremans W, Bujan W, Neve P, et al. CD71 phenotype and the value of gallium imaging in lymphomas. Am J Hematol 1991 ;36:215-216. 24. Tsuchiya Y, Nakao A, Komatsu T, et al. Relationship between gallium-67-citrate scanning and transferrin recep tor expression in lung diseases. Chest 1992; 102:530-534. 25. Kwan AJ, Zimmerman RE, Keech FK, et al. Gallium-67 image contrast: relationship to energy peak and window width selection. Clin NucA-Med 1995;20:860. 26. Front D, Israel O, Epelbaum R, et al. Gallium-67 SPECT before and after treatment of lymphoma. Radiologi' 1990;175:515-519. 27. Harwood SJ, Carroll RG, Anderson M, et al. SPECT gallium scanning for lymphoma and infection. Clin NucAMed 1987;12:694-702. 28. Rossleigh MA, Murray IP, Mackey DW, et al. Pediatrie solid tumors: evaluation by gallium-67 SPECT studies. J NucA-Med 1990;31:168-172. 29. Tumeh SS, Rosenthal DS, Kaplan WD, et al. Lym phoma: evaluation with 67Ga SPECT. Radiology 1987; 164:111-114. 30. Bar-Shalom R, Ben-Arie Y, Gaitini D, et al. Gallium-67 uptake in a mass of benign transformation mimicking recurrence of nodular lymphocytic predominance Hodgkin's disease. J NucA-Med 1994;35:465-468.

Frederick L. Datz, James E. Seabold, Manuel L. Brown, Lee A. Forstrom, Bennett S. Greenspan, John G. McAfee, Christopher J. Palestre, Donald S. Schauwecker and Henry D. Royal University of Utah Medical Center, Salt Lake City, Utah; University of Iowa Hospitals and Clinics, Iowa City, Iowa; University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania; Mayo Clinic, Rochester, Minnesota; Harry S. Truman VA Medical Center, Columbia, Missouri; George Washington University Hospital, Washington, D.C.; Long Island Jewish Medical Center, New Hyde Park, New York; Wishard Memorial Hospital, Indianapolis, Indiana; and Mallinckrodt Institute of Radiology, St. Louis, Missouri

Goldenberg, D. M.; Pinsky, C. M.; Datz, F. L.; Harwood, S. J.; Quenzer, R. W.; Hung, C. Author Information

Computed tomography (CT) and magnetic resonance imaging (MRI) are excellent modalities for imaging patients with localizing signs of an intra-abdominal abscess. However, radionuclide techniques have an advantage over CT and MRI because they can evaluate the entire body for infection. In addition, radionuclides can noninvasively differentiate infection and inflammation from benign fluid collections. Radiopharmaceuticals available for imaging abdominal infection include gallium-67 citrate, indium-111, and technetium-99m-labeled leukocytes, and radiolabeled whole antibodies. The use of these radiopharmaceuticals for abdominal imaging is dependent on their biodistribution and mechanism of abscess localization.

UNLABELLED:Indium-111-polyclonal IgG is a new imaging agent of infection and inflammation that has been developed as a possible replacement for radiolabeled leukocytes. We undertook a study to determine the safety, biodistribution and dosimetry of the agent in normal subjects.METHODS:Twelve normal male volunteers with an average age of 34 yr (range 21-55 yr) were studied. Each was injected with 1.22-1.47 mCi 111In-labeled polyclonal IgG; digital whole-body images, in addition to blood, urine and fecal samples, were obtained immediately after injection and at 6, 24, 48, 72, 96 and 120 hr. Whole-body counts, as well as individual organ data obtained by outlining regions of interest, were measured. Blood, urine and fecal counting were done in a well counter and compared to known standards; dosimetry calculations were performed with the MIRD technique.RESULTS:The mean whole-blood activity had a two-phase disappearance curve: the T1/2I was 11.4 hr (61.1%) and the T1/2II was 112.5 hr (38%). Twelve percent of the dose was excreted in the urine and 1.14% in the feces. Skeletal muscle had the highest percentage of uptake, followed by the bone marrow, liver and lungs; the spleen showed less than 1% uptake. Activity in the lungs varied with time, falling by 37% after 18 hr and by 68% after 72 hr. Dosimetry calculations indicated that the highest absorbed dose was to the liver (1.42 rad/mCi) followed by the testes (1.23 rad/mCi) and red marrow (0.976 rad/mCi). The total-body dose was 0.467 rad/mCi, with an effective dose equivalent of 790.84 mrem.CONCLUSION:The biodistribution of 111In IgG is similar to that of 99mTc-HMPAO-labeled leukocytes. Activity in the liver, kidneys and GI tract may make evaluation of infection in these regions difficult. The dosimetry data indicate that adequate doses can be administered for clinical imaging without exposing the patient to excessive radiation.

In this paper a method of modeling the distribution of scattered events in emission projection data is developed and applied. This method is based on the use of a transmission map to define the inhomogeneous scattering object. The key point is the use of the set of line integrals calculated as part of the attenuation correction technique, as the basis of a model of the distribution of scattered events. The probability of a photon being scattered through a given angle and being detected in the emission energy window is approximated using a Gaussian function. The parameters of this Gaussian are determined using Monte Carlo generated parallel-beam scatter line spread functions from a nonuniformly attenuating phantom. The model is incorporated into a two-dimensional projector-backprojector and used with the Expectation-Maximization-Maximum-Likelihood algorithm for the reconstruction of fan-beam phantom data. The correction is shown to perform well for a phantom that varies slowly in the axial direction. For the more clinically realistic situation of a torso phantom, the method produces improvements in terms of blood pool to myocardium contrast, but does not restore the contrast to the level exhibited in a reconstruction from "scatter free" data.

Separate imaging studies employing Tc-99m MDP, In-111 labeled leukocytes, and Tc-99m SC were performed in a patient receiving external beam radiation therapy to the mediastinum and left hemithorax. The leukocyte scan demonstrated greatly increased activity at the site of the radiation port. The bone marrow (sulfur colloid) scan was normal and the bone scan demonstrated only minimally increased activity in the irradiated region. The varying appearance of these scans may represent the difference in the early effect of radiation on bone and bone marrow elements.

A 24-year-old female gymnast had a 3-month history of bilateral forearm pain. A Tc-99m MDP bone scan demonstrated focally increased activity in the radial shafts on blood pool and delayed images, characteristic of fatigue fractures. Fatigue fractures commonly occur in the lower extremities. Upper extremity fatigue fractures, in contrast, are uncommon and usually involve the humerus or ulna. Fatigue fracture of the radial shaft from gymnastic exercise has not been previously reported.

The purpose of this study was to determine the efficacy of In-111-polyclonal immunoglobulin (IgG) for the diagnosis of infection or inflammation. Methods: Fifty-three patients with suspected infection were prospectively studied. Each underwent an In-111-polyclonal IgG study; biopsy, surgery, additional nuclear medicine scans and radiographic studies were used to confirm the IgG scan results. Results: The polyclonal IgG scan had a sensitivity of 97.9% and a specificity of 94% for infection or inflammation. When only infection or severe inflammation such as bowel infarction was considered, the sensitivity remained the same but the specificity fell to 83%. Chronic infections were detected equally as well as acute infections. Antibiotics, steroids, anti-inflammatory agents, diabetes and diminished renal function did not affect scan sensitivity. There were no adverse reactions to the radiopharmaceutical. Three patients underwent extended imaging. Their scans stayed positive for an average of 8 days. Three patients treated for infection had their scans turn negative on repeat study, confirming the efficacy of their antibiotic therapy. Conclusion: Indium-111-polyclonal IgG is an effective imaging agent of infection and/or inflammation that is useful in a variety of infections and in severe inflammatory diseases. The ease of preparation and safety make it an attractive alternative to labeled leukocytes.