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C J Palestro

Publications and source records attributed to C J Palestro.

At least 37 records · Page 2Linked to original sources
PubMed1997

Leukocyte-marrow scintigraphy in hyperostosis frontalis interna.

Hyperostosis frontalis interna is the term used to describe the thickening of the frontal bones of the skull. This thickening of the frontal bones is accompanied by an increase in the diploic space which results in an increased quantity of hematopoietically active marrow. Increased frontal bone uptake of labeled leukocytes has been reported in this condition, and the symmetric appearance of this activity may suggest its benign etiology. We have encountered a case of hyperostosis frontalis interna in which the uptake of labeled leukocytes was asymmetric and marrow scintigraphy confirmed that the activity seen was due to marrow not infection.

Aged↗
PubMed1996

Evaluation of four radiopharmaceuticals for imaging inflammation in a rabbit model of arthritis.

We compared the utility of four radiopharmaceuticals; 111In-chloride, 67Ga-citrate, 111In labeled leukocytes (WBCs) and 99mTc-MDP for assessing the inflammatory response in antigen induced arthritis in a rabbit model. A total of 20 rabbits, divided into four equal groups, were included in this study. Each group was studied twice with a single radiotracer; a baseline study and a follow-up study after induction of the arthritis. Knee to knee, knee to whole body, and knee to liver (except for the group studied with 99mTc-MDP) ratios were generated. Knee to knee ratios showed no significant change from baseline to arthritis studies in any of the four groups. Significantly increased knee to total body ratios were seen in all of the groups, except for the group studied with 99mTc-MDP. The greatest increase was seen in the group studied with 111In-chloride. Significantly increased knee to liver ratios were observed in all three groups for which these ratios were generated and again the greatest increase was observed in the group studied with 111In-chloride. In summary, based on the higher uptake observed in this group, of the four radiotracers evaluated, 111In-chloride is probably the most useful for monitoring the inflammatory response in antigen induced arthritis. The symmetry of the response suggests that it may also be useful in monitoring the response to therapy.

Animals↗
PubMed1996

Rapid imaging of infections with a monoclonal antibody fragment (LeukoScan).

The diagnostic accuracy for imaging infection with a technetium-99m-labeled antigranulocyte Fab' fragment (LeukoScan) was prospectively examined in a multicenter study. Scintigraphy was performed in 53 patients at 1 to 6 hours and at 24 hours after injection of the labeled antibody fragment. Thirty-nine sites of infection were detected and confirmed by histologic study, cytologic study, other imaging procedures, or by followup. Thirty-eight of the 53 patients also were studied with technetium-99m-Exametazim or indium-111-oxine labeled leukocytes within 1 week of the LeukoScan study. In 21 patients with 25 osteomyelitic lesions, LeukoScan recognized 13 of the lesions as being true positive ones, 10 as being true negative ones, and 2 as being false negative ones, whereas the leukocyte scan showed 9 true positive results, 5 true negative results, and 2 false negative ones. Sensitivity specificity, and diagnostic accuracy of LeukoScan were 90.0 %, 84.6 %, and 87.9 %; and with autologous leukocyte scintigraphy were 83.9%, 76.5%, and 81.3%, respectively. The sensitivity of LeukoScan was independent of the amount of the labeled antibody injected (0.1 - < 0.5 mg, 96.2%; 0.5 - < 0.9 mg, 80.0%; 0.9 - 1.0 mg, 77.8%). False positive lesions were detected in a periprosthetic calcification, a frontal hyperostosis, and 2 periprosthetic hips that had loosened. Human antimouse antibody could not be detected in any of the 13 patients tested 1 or 3 months after injection. LeukoScan is suitable for imaging infectious lesions and may have diagnostic advantages compared with autologous leukocyte scintigraphy.

Adult↗
PubMed1995

Radionuclide imaging after skeletal interventional procedures.

Although nuclear medicine is often used as an adjunct to planning skeletal therapeutic interventions, its role in the assessment of these various interventional procedures, after the fact, is equally important. Skeletal therapeutic interventions studied with radionuclide imaging include bone grafts, the postoperative spine, and joint replacements. Vascularized bone grafts allow the successful reconstruction of large bone gaps. Early detection of vascular compromise permits prompt reevaluation of the vascular anastomosis so that potentially reversible causes of ischemia can be corrected. Radionuclide bone scintigraphy is a simple noninvasive method to evaluate the anastomotic patency of these grafts. Scintigraphically, vascular patency is characterized by normal or diffusely increased tracer uptake throughout the graft, whereas failure of the graft presents as photopenia. Bone scintigraphy, especially single photon emission computed tomography (SPECT), is of considerable value in the work-up of patients with persistent back pain after spinal surgery. Postoperatively, spinal fusion is characterized by diffusely increased uptake of radiotracer in the fused area. In contrast, focally increased uptake has been shown to be related to bony nonunion or pseudoarthroses. In patients who have undergone laminectomy, SPECT bone scintigraphy can localize the level of maximum instability and vertebral stress. The radionuclide evaluation of joint replacement complications, especially of hip and knee prostheses, has been extensively studied for nearly 2 decades. Bone scintigraphy is probably most useful when the images are normal. Although periprosthetic sites of increased uptake may be indicative of postoperative problems such as loosening or infection, they may also merely reflect postoperative changes. Dual tracer studies, focusing primarily on the diagnosis of the infected joint replacement, have consequently become the norm. Bone-gallium scintigraphy was the earliest dual tracer modality used, with an accuracy of 60% to 80%. The current radionuclide study of choice for diagnosing the infected prosthesis is labeled leukocyte-marrow imaging. Both leukocytes and colloid tracers accumulate in marrow, whereas only leukocytes accumulate in infection. This technique facilitates the discrimination of labeled leukocyte uptake in aberrant, but not abnormal, marrow from uptake in infection. The reported accuracy of this technique consistently exceeds 90%.

Bone Transplantation↗
PubMed1995

Radiation-induced lung injury using a pig model. Evaluation by high-resolution computed tomography.

RATIONALE AND OBJECTIVES: To assess the early phase of radiation-induced lung injury using high-resolution computed tomography (CT) under experimental conditions and to perform precise CT-pathologic correlation. METHODS: Five Yorkshire pigs received a single dose of 12.5 Gy to the right lower lung. Computed tomographic images were obtained at 2-week intervals. The animals were killed after follow-up periods of 4-16 weeks. The lungs were removed, inflated, fixed, dried, and sliced corresponding to the CT sections. Computed tomography, specimen radiography, and histologic findings were correlated. RESULTS: Various CT findings were observed during the first 16 weeks, including ground-glass opacity, discrete consolidation, patchy consolidation, thickened interlobular septum, and bronchovascular bundle. Ground-glass opacity was associated with thickened alveolar wall and scattered tiny fibrotic foci. Thickened interlobular septum and bronchovascular bundle were the results of fibrosis adjacent to these structures. Discrete consolidation correlated with intraalveolar edema with hemorrhage and infiltration of inflammatory cells. CONCLUSIONS: High-resolution CT correlated well with pathology of the lung due to radiation injury as verified by precise radiologic-pathologic correlation.

Animals↗
PubMed1995

The role of gallium and labeled leukocyte scintigraphy in the AIDS patient.

Because AIDS patients frequently present with minimal symptomatology, radionuclide imaging with its ability to survey the entire body, is especially valuable. Gallium-67 citrate, the most commonly performed radionuclide study for localizing infection in these patients, is most useful for detecting opportunistic infections, especially in the thorax. A negative gallium scan, particularly when the chest X-ray is unremarkable, rules strongly against pulmonary disease. A negative gallium scan in a patient with an abnormal chest X-ray and Kaposi's sarcoma, suggests that the patient's respiratory distress is related to the neoplasm. Diffuse pulmonary parenchymal uptake of gallium in the HIV (+) patient is most often associated with PCP. While there are other causes of diffuse pulmonary uptake, the more intense or heterogeneous the uptake, the more likely the patient is to have PCP. Focal pulmonary uptake is usually associated with bacterial pneumonia although PCP may occasionally present in this fashion. Lymph node uptake of gallium is usually associated with Mycobacterium avium complex, tuberculosis, or lymphoma. When corresponding abnormalities are present on thallium scintigraphy lymphoma is likely. Gallium positive, thallium negative, studies suggest mycobacterial disease. Labeled leukocyte imaging is not useful for detecting opportunistic infections probably because of the inflammatory response incited by these organisms. Leukocyte imaging is, however, more sensitive for detecting bacterial pneumonia. In the abdomen, gallium imaging is most useful for identifying lymphadenopathy, while labeled leukocyte imaging is superior for detecting AIDS-associated colitides. In summary, radionuclide studies are valuable diagnostic modalities in AIDS. Their success can be maximized by tailoring the study to the individual's needs.

AIDS-Related Opportunistic Infections↗
PubMed1994

The current role of gallium imaging in infection.

The role of gallium imaging in infection has changed considerably during the past several years. Once the mainstay of radionuclide imaging of infection, it has been supplanted to a very great extent by labeled leukocyte imaging. Despite the success of the labeled white-cell technique, gallium still plays an important role in the radionuclide evaluation of infection. It is not possible, for a variety of reasons, to perform white-cell imaging on all patients, and gallium imaging is certainly an acceptable substitute. In certain circumstances, rather than merely being a substitute, gallium is an important complement to leukocyte imaging. This is best illustrated by the patient with a fever of unknown origin (FUO). Although a negative leukocyte study effectively excludes an acute infection, it fails to identify the source of the patient's fever, a not uncommon situation in view of the fact that only approximately 25% of all FUOs are caused by infection. A complementary gallium study under these circumstances may identify either a chronic infectious process or even a neoplasm, conditions for which white-cell imaging is relatively insensitive. Although leukocyte imaging is probably superior to gallium for most infections of the musculoskeletal system, this technique is of limited value in patients with suspected vertebral osteomyelitis. There are data that suggest that sequential bone gallium imaging may be a better way to diagnose this entity. Finally, in immunocompromised patients, gallium imaging is clearly the procedure of choice for detecting the opportunistic respiratory infections and lymph node abnormalities that are so prevalent in this population.

Abdomen↗
PubMed1993

Specificity and sensitivity of distinctive chest radiographic and/or 67Ga images in the noninvasive diagnosis of sarcoidosis.

An analysis of gallium-67 (67Ga) uptake in the lacrimal and salivary glands and intrathoracic lymph nodes was made in 162 patients with sarcoidosis, consisting of a large number with chronic "fibrotic" disease, and 167 HIV-positive patients (most of whom have/had AIDS). This study was designed to further assess the diagnostic sensitivity and to fully evaluate the diagnostic specificity of chest radiographic and/or 67Ga uptake findings found to be characteristic of sarcoidosis. A lambda 67Ga uptake image or a panda 67Ga uptake image with associated bilateral, symmetrical hilar lymphadenopathy (BSHL) or bilateral, symmetrical parenchymal infiltration indicative of pulmonary fibrosis on chest radiograph (BSIF) was commonly present in sarcoidosis. These distinctive 67Ga uptake images were frequently observed in patients with normal chest radiographs (stage 0 [33 percent]), as well as in patients with BSHL on chest radiograph whether the disease was in an "early" stage, ie, stages I (74 percent) and II (90 percent) or a chronic "fibrotic" stage, ie, IVa (71 percent). A panda 67Ga uptake image was observed in 8 percent of HIV-positive patients; however, a lambda 67Ga uptake image alone or any of the other chest radiographic and/or 67Ga uptake patterns distinctive for sarcoidosis were not observed in any of 167 HIV-positive patients. We conclude that (1) a lambda 67Ga thoracic image (usually associated with a panda 67Ga uptake image) or a panda 67Ga uptake image together with BSHL or BSIF on chest radiograph represent distinctive patterns that are highly specific and sensitive for the noninvasive diagnosis of the majority of sarcoidosis patients, and (2) the finding of a panda 67Ga uptake image, not associated with BSHL or BSIF on chest radiograph, should suggest, in addition to a limited number of readily diagnosable disorders, the presence of a positive HIV status.

Gallium Radioisotopes↗