Donor-leukocyte imaging in granulocytopenic patients with suspected abscesses: concise communication

Indium-111-labeled donor leukocytes were used for the detection of foci of suppuration in eight severely leukopenic patients with marrow suppression, either idiopathic or associated with chemotherapeutic regimens for leukemia. In three patients good correlation was found between the results of imaging and clinical signs or subsequent proof of inflammation. In the other five patients, in whom no evidence of localized suppuration occurred, no abnormal accumulations of radioactivity were demonstrable. Labeled donor leukocytes provide a method for locating suppurative foci in severely leukopenic patients in whom autologous leukocyte labeling is impractical.     

Skeletal scintigraphic changes in osteoporosis treated with sodium fluoride: concise communication

An appendicular skeletal response to sodium fluoride (NaF) was detected by total skeletal scintigrams. Twelve postmenopausal osteoporotic women were treated with NaF (88 mg/day) and calcium (1500 mg/day). Total skeletal scintigrams were obtained before and during treatment. Within 4 to 21 mo (mean: 8.3), all 12 patients showed new areas of increased uptake corresponding to metaphyseal regions and short bones of the appendicular skeleton. The number of peripheral bones involved in each subject ranged from four to 12. The most frequently involved sites (11 of 12 patients) were the right distal femur and proximal tibia. Nine patients showed an increase in serum alkaline phosphatase activity, which was attributed to an increase in the skeletal isoenzyme. Seven of 12 patients developed bone pain in one or more of the regions of increased uptake. This study establishes that the skeletal scintigram is a sensitive index of the peripheral skeletal response to NaF.     

Indium-111 chloride imaging in patients with suspected abscesses: concise communication

Two hundred and fifty-eight patients with clinically suspected inflammatory processes were studied. Seventy-two images were categorized as true positive; 211 as true negative. There were nine false-positive studies, four of which were due to activity in beds of excised organs. There were six false-negative studies, four of which were due to walled-off abscesses found either at surgery or biopsy. The sensitivity was 92%, the specificity 95%, and the accuracy 94%. This study shows that indium-111 chloride imaging provides a reliable way to locate inflammatory processes and overcomes the disadvantages of other imaging agents, for example gastrointestinal activity or the demonstration of healing surgical wounds with gallium-67, and the false-positive images due to cystic fibrosis and other respiratory diseases, or accessory spleens as seen with In-111-labeled white cells.     

Utility of three-phase skeletal scintigraphy in suspected osteomyelitis: concise communication

Three-phase skeletal scintigraphy, consisting of a radionuclide angiogram, an immediate postinjection "blood-pool" image, and 2--3 hr delayed images, was performed on 98 patients with suspected osteomyelitis. This procedure was evaluated by first interpreting only the delayed images, next the combination of "blood-pool" and delayed images, and finally the three-phase study. There was no change in the sensitivity (12/13 = 0.92) for detecting osteomyelitis, but the false-positive rate for osteomyelitis decreased from 0.25 (21/85) to 0.06 (5/85). In 21 of 64 patients (33%) with abnormal studies, the "blood-pool" image and/or the radionuclide angiogram led to a more accurate scintigraphic diagnosis. In 12 patients (19%) the "blood pool" alone was enough to achieve the correct final diagnosis and was used most often to identify noninfectious skeletal disease. In 9 patients (14%) the radionuclide angiogram was required for an accurate interpretation and was considered essential most often in cases of soft-tissue infection. Both radionuclide angiography and "blood-pool" imaging appear to augment the specificity of skeletal scintigraphy in patients with suspected osteomyelitis.     

Scintigraphic imaging with tantalum-178 and the Anger scintillation camera: concise communication

Tantalum-178 is a short-liver radionuclide (T 1/2 = 9.3 min.) and emits primarily 56- to 64-keV characteristic x-rays. We have determined the imaging characteristics with this radionuclide and a large-field-of-view Anger camera. With a pinhole collimator, good spatial resolution is possible with Ta-178, although the image quality is superior with Tc-99m under comparable conditions. Spatial resolution with parallel-hole or converging collimators was much less satisfactory with Ta-178 because of septal penetration by high-energy photons. Pulmonary perfusion and liver-spleen images of excellent quality were obtained in the rabbit using the pinhole collimator and Ta-178-labeled agents.     

Functional asplenia in patients with chronic graft-versus-host disease: concise communication

Liver/spleen images were performed with technetium-99m sulfur colloid in 53 patients who had undergone bone-marrow transplantation. The spleen was not seen in the images in five out of the ten patients with chronic graft-versus-host disease (GVHD). None of the five had a history of splenectomy. In two of these patients, anatomical presence of the spleen had been documented earlier by scintigram. The spleen was visible in all seven patients with acute and in all 36 patients without GVHD. Neither the differences in methods of treating the patients before bone-marrow transplantation nor the time lapse between transplantation and the liver/spleen image correlated with the observed effect among these three groups of transplant patients. We conclude that there is a high association between chronic GVHD and functional asplenia.     

The specific scintigraphic pattern of "shin splints in the lower leg": concise communication

The clinical entity, "shin splints," is now being recognized, and more specifically characterized by the findings of exercise-induced pain and tenderness to palpation along the posterior medial border of the tibia. In this prospective study, ten patients with this syndrome were evaluated using three-phase bone scintigrams, and a specific scintigraphic pattern was determined. Radionuclide angiograms and blood-pool images were all normal. On delayed images, tibial lesions involved the posterior cortex, were longitudinally oriented, were long, involving one third of the length of the bone, and often showed varying tracer uptake along that length. Obtaining both lateral and medial views was crucial. The location of activity suggested that this entity is related to the soleus muscle. These scintigraphic findings can be used to differentiate shin splints from stress fractures or other conditions causing pain in the lower leg in athletes.     

The blood-tissue barrier of human brain tumors: correlation of scintigraphic and ultrastructural findings: concise communication

Through the first 2 hr, uptake of [Tc-99m]pertechnetate and of Co-57 bleomycin were assessed in 29 brain tumors and were correlated with the ultrastructure of the tumor's capillary endothelium. No difference in uptake was found between the two tracers. Permeability of brain tumors to these agents was found to be governed by the same ultrastructural features that determine permeability in experimental brain tumors: the type of junction between contiguous endothelial cells in the capillaries. Meningiomas, which showed very high uptake of the radiotracers, demonstrated open or punctate junctions with short fusion of apposed membranes. They also showed a large number of pinocytotic vesicles and fenestrae. Capillaries of tumors without uptake had a small number of short tight junctions (less than 0.25 mu) between adjacent endothelial cells and a relatively large number of long junctions (greater than 0.5 mu). In intracerebral tumors that showed relatively high uptake, the reverse was true: most of the junctions were short and only a few long junctions were found. That uptake of [Tc-99m]pertechnetate and of Co-57 bleomycin depends on tumor capillary ultrastructure (which determines the permeability) suggests the possibility of the use of radiopharmaceuticals as in vivo indicators of tumor permeability. Brain scintigraphy may help to asses brain-tumor availability to non-lipid-soluble chemotherapeutic drugs.     

Pharmacokinetics of hepatobiliary imaging agents in rats: concise communication.

The distribution and elimination kinetics of Tc-99m pyridoxlidene glutamate (Tc-99m PG), of Tc-99m N-(2,6-dimethyl-phenylcarbamoylmethyl) iminodiacetic acid (Tc-99m HIDA), and of I-131 rose bengal in blood were quantitated after i.v. injection in rats. This was performed by use of a unique indwelling catheter that externalizes the systemic circulation, permitting continuous monitoring of blood radioactivity. The blood activity-time curves of Tc-99m PG and Tc-99m HIDA are described by the sum of three exponential functions. Only two exponentials are required in the case of I-131 rose bengal. The rank order for the rates of loss from blood was Tc-99m HIDA less than Tc-99m PG less than I-131 rose bengal. Bile was collected after administration of Tc-99m HIDA and Tc-99m PG. The total excretion of radioactivity over a 70-min period amounted to 95.7% and 42.8% of the dose of Tc-99m HIDA and Tc-99m PG, respectively. A linear compartmental kinetic model was developed to account for the disappearance from blood and the biliary excretion of these radiopharmaceuticals in rats.     

Evaluation of three imaging instruments in dogs with liver hemotomas: concise communication.

Single-gamma emission computerized tomography (ECT) was compared with transmission computerized tomography (TCT) and scintillation-camera imaging (SC) in eight dogs with acute, solitary hematomas in the left liver lobe. The superior performance of TCT was attributed to its inherently better spatial resolution than those of ECT or SC, and to the fact that studies with TCT could be performed during apnea. ECT was more sensitive than SC to small changes in the spatial distribution of radionuclides. In addition, the ECT, by virtue of its sectioning capability, was more sensitive than is SC to differences in radionuclide concentrations at same depth in an organ.     

Osteonecrosis in patients with systemic lupus erythematosus: MR imaging and scintigraphic evaluation

This study was to describe the findings of osteonecrosis in patients with SLE at MR and scintigraphic imaging. Among 415 patients with SLE, 37 patients were diagnosed to have osteonecrosis. MR images and bone scintigraphs were analyzed for sites of involvement, signal intensity, bilaterality and multiplicity. MR imaging features of osteonecrosis in patients with SLE included isointense signal intensity relative to adjacent bone marrow, hypointense rim, marginal enhancement and unusual involvement of flat bones. Bilateral and multiple involvements were common.     

Bone scintigraphy in the initial staging of patients with renal-cell carcinoma: concise communication

We reviewed the records of 40 consecutive patients who received bone scintigraphy in conjunction with the initial evaluation and staging of renal-cell carcinoma, to determine the role of bone imaging in this clinical context. Bone scintigrams were positive in three out of 40 patients at the time of diagnosis. In view of the low yield of bone imaging, it appears that routine scintigraphy is unwarranted in the absence of skeletal symptoms before the diagnosis of renal lesions. The presence of a positive bone image did not alter the indication for nephrectomy.     

A comparison of skeletal uptakes of three diphosphonates by whole-body retention: concise communication

Twenty normal volunteers had measurements of 24-hr whole-body retention (WBR) of three structurally related Tc-99m-labeled phosphonate skeletal imaging agents: (1-hydroxyethylidene) diphosphonate (HEDP), methylene diphosphonate (MDP), and hydroxymethylene diphosphonate (HMDP). The average WBR values, reflecting skeletal uptake, were 18.4, 30.3, and 36.6%, respectively. These results clearly illustrate that slight alterations in diphosphonate molecular structure have a significant effect upon specificity for osseous tissue, and thus may affect skeletal image quality and the usefulness of the WBR technique in diagnosing metabolic bone disease.     

Technetium-99m glucoheptonate imaging in lung cancer and benign lung disease: concise communication

We prospectively studied technetium-99m glucoheptonate (Tc-GHA) uptake in 58 patients with newly diagnosed lung cancer and in 20 patients with pulmonary inflammatory disease or metastatic carcinoma. Fifty-three (91%) primary tumors accumulated Tc-GHA: squamous cell 20/22, adenocarcinoma 7/7, large cell 10/11, and small cell 16/18. Intensity of tumor uptake was greatest in small-cell cancer. Supraclavicular metastases were detected in two patients. Fourteen patients with mediastinal evaluation by Tc-GHA imaging and trispiral tomography underwent mediastinoscopy or thoracotomy. Five of ten patients with negative mediastinum by tomography and Tc-GHA imaging showed metastases by biopsy (false-negative Tc-GHA). Less intense accumulation of Tc-GHA was observed in 18/20 cases of pulmonary inflammatory disease or pulmonary metastases. Although Tc-GHA accumulates by an unknown mechanism in primary lung cancer, we cannot recommend its use in detecting mediastinal spread of lung cancer due to its unacceptably high false-negative rate.     

Xenon-133 retention in hepatic steatosis-correlation with liver biopsy in 45 patients: concise communication

This study presents the results of comparison of hepatic fat content with hepatic xenon retention in 45 patients. The degree of hepatic Xe-133 retention was measured during pulmonary ventilation studies. The amount of hepatic steatosis was graded 0 to 4+ on histologic liver sections obtained by needle or surgical biopsy. There was agreement between the amount of hepatic xenon retention determined scintigraphically and the degree of steatosis determined histologically. These results suggest that Xe-133 retention in the liver provides a simple means of evaluating fatty infiltration of the liver. The potential of this technique as a noninvasive means of investigating hepatic fatty infiltration is discussed.     

Ovarian imaging by the binding of radioiodinated chorionic gonadotropin: concise communication.

Previous studies have demonstrated the presence of specific, high-affinity receptors for human chorionic gonadotropin (HCG) in human and rat ovaries. In the present study, highly purified HCG was labeled with iodine-131 and used for the imaging of luteinized rat ovaries. Excellent images were obtained. The accumulation of radioactivity in the ovaries was completely inhibited by previous administration of excess unlabeled HCG. Time-course studies show that radioiodinated HCG was rapidly accumulated within 1 hr and largely cleared from the ovary at 24 hr. These results show the potential for imaging of endocrine target tissues by hormone-receptor binding, and the possibility of quantitation of hormone receptors in tissues under pathological conditions.     

Faster assessment of patients receiving unnecessary thyroid treatment: concise communication

Forty-five consecutive patients on thyroid hormone treatment without obvious indication were evaluated. Twenty-five of these cases were found to have no evidence of thyroid disease. Biochemical testing was not helpful in making the diagnosis of hypothyroidism in the majority of thyroid-treated hypothyroid patients. Normal technetium images were obtained in 25 patients, 22 of which had no thyroid disease. In contrast, abnormal technetium images were obtained in 20 patients, 16 of whom were thought to be hypothyroid, and one of whom developed a goiter within 2 mo after discontinuing levothyroxine. The use of technetium imaging seems useful for the rapid (20 min) evaluation of those patients likely to benefit from discontinuing thyroid medication.     

Decreased sensitivity of early imaging with In-111 oxine-labeled leukocytes in detection of occult infection: concise communication

Imaging with leukocytes labeled with indium-111 oxine is a sensitive technique for detecting sites of occult infection. Traditionally, imaging is performed 24 hr after injection. We undertook a prospective study of 35 patients (40 studies) with possible occult infection to see whether a 24-hr delay in imaging is really necessary. Patients were imaged at 1-4 hr and again at 24 hr after injection. The early images had a sensitivity of only 33%, compared with 95% for the 24-hr images. Of the seven studies that were positive on both early and delayed images, 71% had more intense uptake at 24 hr. There were no false-positive early images. We conclude that imaging 1-4 hr after injection with In-111 oxine-labeled leukocytes has a low sensitivity for detecting occult infection. However, a positive early image is specific for a site of infection.     

Gorlin's syndrome: diffuse appendicular skeletal involvement with scintigraphic correlation

Gorlin's syndrome (also known as basal cell nevus syndrome, Gorlin-Goltz syndrome, and nevoid basal cell carcinoma syndrome) is a rare, inherited disorder characterized by multiple basal-cell epitheliomas, intracranial calcification, keratocysts of the mandible, and unusual and striking skeletal abnormalities. We present the interesting case of a 45-year-old woman who was informed that she had fibrous dysplasia of the extremity at another institution before extensive radiological work-up showed a diffuse skeletal process. The skeletal abnormalities, in conjunction with the patient's history of multiple basal cell carcinomas, is consistent with the diagnosis of Gorlin's syndrome. We describe this unusual case of striking radiological and scintigraphic findings in a patient with Gorlin's syndrome.     

Gallbladder dynamics induced by a fatty meal in normal subjects and patients with gallstones: concise communication

A study was undertaken to establish the pattern of gallbladder emptying in normal subjects and in patients with gallstones, using a fatty meal as stimulus to release endogenous cholecystokinin. The time from meal ingestion to beginning of gallbladder emptying (latent period), the total duration of emptying (ejection period), degree of emptying (ejection fraction), and the rate of emptying (ejection fraction/ejection period) were measured noninvasively by a nongeometric scintigraphic technique. The mean latent period and ejection rate were similar in normal subjects and patients with gallstones, but the mean ejection period and ejection fraction were significantly reduced in the patients. This study suggests that for an identical stimulus, the gallbladder in cholelithiasis begins to empty at the normal time but empties for a shorter duration; the result is a reduction of ejection fraction but not of ejection rate.