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The quality of Tc-PP scans is best in younger patients. In all age groups quality is adversely affected by free TcO4-. This should be suspected if excessive background is present or marked accumulation is noted in the thyroid gland. Direct physician supervision of all studies is recommended. Symptomatic and roentgenographically positive areas may then be determined for special interpretative attention. Objects which attenuate activity should be removed or noted. Potential sources of superficial contamination (product spill, urine, saliva) must be known and considered when extraneous activity does not correlate with skeletal structures or clinical findings. Normal variations in skeletal uptake of Tc-PP include asymmetries between periarticular areas on the right and left, local increases due to physiologic calvarial thickening and uptake in persistently visualized sternal ossification centers. Apparent variations in the vertebral activity may be due to focal plane effects of rectilinear scanners. Hyperemia can cause diffusely increased Tc-PP localization in an entire extremity. This effect may completely obscure a lesion or obscure the extent of a lesion. Tc-PP excretion through the kidneys occasionally provides useful morphologic or functional information concerning the urinary tract which should be inspected on all scans. Abnormal soft tissue uptake occurs in a variety of conditions including healing wounds and some malignant tumors. A large percentage of patients over 40 years of age demonstrate localization of Tc-PP in the walls of the femoral vessels.

A scintigraphic pattern is described for bone scans with 99m-Tc-polyphosphate and 99m-Tc-diphosphonate in which abnormal tracer accumulation extends beyond the known limits of certain skeletal lesions. The associated pathologic entities include benign and malignant tumors, infection, and trauma. The pathogenesis of "extended patterns" has not been proved but probably relates to regional hyperemia induced by associated lesions. Increased blood flow results in more tracer delivery to otherwise normal bone in the "watershed" areas of hyperemia, producing these patterns.

The sensitivity and specificity of 99mTc-sulfur colloid liver-spleen imaging in diffuse hepatocellular disease and the significance of image patterns found in these diseases are presented. By visually quantifying the image alterations found in biopsy-proven cases of diffuse hepatocellular disease and analyzing the correlation between the histological diagnosis and the quantified image alteration (individually and by groups), the 99mTc-sulfur colloid liver-spleen image was found to be highly sensitive (83%). Relative discriminatory values were derived for each image finding and a specific image pattern was found in cirrhosis.

Two cases of osteosarcoma of the femur are presented. In both patients, bone scans confirmed the presence of pulmonary metastases. 99mTc-polyphosphate (TcPP) localizes in the extraskeletal pulmonary metastases, including some not demonstrated radiographically. Thus the TcPP scan is a valuable adjunct in the staging and therapeutic planning of patients with primary malignant bone tumors.

A method for quantifying thyroid gland iodine content using a modified fluorescence scanning system is described. The technique does not require a computer. Two single channel analyzers and digital scalers are used to determine net counts from iodine k-alpha x-rays and system response in counts per milligram is calibrated from studies of known quantities of iodine placed in thyroid phantoms. Fluorescence quantification of thyroid gland iodine content was performed in 250 patients with a wide variety of thyroid disorders. Thirty euthyroid patients judged to have no evidence of thyroid disease averaged 10.1 +/- 3.9 mg glandular iodine. Results for several major diagnostic categories were: untreated Graves' disease, 28 patients, 24.4 +/- 9.9 mg; diffuse euthyroid goiter, 14 patients, 16.1 +/- 7.4 mg; primary hypothyroidism, seven patients, 0.5 mg; and nontoxic multinodular goiter, 28 patients, 7.3 +/- 4.1 mg. Follow-up studies on patients treated for Graves' disease both medically and with 131I generally revealed elevated iodine contents in persistently hyperthyroid patients, lower than normal average amounts in euthyroid patients, and only trace amounts in hypothyroid patients. Although the clinical role of fluorescence iodine quantification remains to be fully established, the technique provides information not otherwise available on an important parameter of thyroid status.

The incidence and significance of solitary bone scan abnormalities were assessed in a study of 1,129 consecutive patients with extraskeletal primary malignancies. Solitary abnormalities were encountered in 172 cases (15%). The etiology of the scan abnormality was established in 90 of the 172 cases: 58 (64%) were due to metastatic disease, and 32 (36%) were secondary to a benign process. A significant percentage of solitary scan abnormalities is due to benign disease processes, even in patients with proved extraosseous malignancies.

SummaryHeterologous antimouse lymphocyte sera were evoked by injecting rabbits with normal mouse thymuses and lymph nodes (ATS and ALS), as well as lymph nodes of mice thymectomized and X-irradiated, and then immunized with typhoid-paratyphoid vaccine (NTALS). Antisera were raised against C57BL/6, Ajax, and C3H inbred mouse strains. The effects were tested on skin allograft survival and peripheral lymphocyte counts. Allograft survival was more prolonged in recipients injected with antisera raised against the donor strains, while peripheral lymphocyte counts were more depressed if the antisera were directed against the recipient strains. While there was minimal prolongation of allograft survival if NTALS was raised against the donor strain, there were no effects of NTALS in any other strain combination, and no significant depression of the lymphocyte counts. Leukoagglutinin titers of ALS, ATS, and NTALS were equal when tested against mouse lymph node lymphocytes. It is suggested that enhancement could have...

SUMMARY The one-way mixed lymphocyte culture (MLC) in unrelated mongrel dogs has been demonstrated to measure both cellular and humoral immunity of unmodified neck kidney allograft rejection. Peripheral blood lymphocytes of five allograft recipients were cultured, together with either lethally X-irradiated donor or indifferent lymphocytes. Either autologous or homologous plasma or inactivated serum was added. In control experiments, stimulating and responding cells from donors, recipients of neck kidney autografts, or normal dogs were combined in MLC, and tritiated thymidine uptake between 15,000 and 30,000 counts/min (CPM) indicated strong responses pre- and postoperatively. By contrast, between 4 and 14 days after allografting there was complete disappearance of recipient lymphocyte reactivity, most specifically against donor lymphocytes, in both autologous and homologous plasma and serum. Tritiated thymidine uptake in these cultures was similar to negative control mixed lymphocytes cultured with X-irradiated autologous lymphocytes (

A thyroid nodule, "hot" by 99mTc and "cold" by 131I scanning, was reimaged with a fluorescent scanner. The fluorescent scan was qualitatively similar to the 131I scan and demonstrated low iodine content in the nodule. This combination of scan patterns is compatible with an organification defect in the nodular tissue.

Of 54 patients with solitary autonomous thyroid nodules (SAN), only one or perhaps two manifested signs or symptoms of hyperthyroidism. Eighteen of the 54 patients had nodules that were larger than 3 cm in diameter, but only one of these patients had possible thyrotoxicosis. Forty-eight of the 54 patients were followed up for 4 to 136 months (average, 24 months). The course of the disease was completely benign, and none of these subjects developed hyperthyroidism during the follow-up. Two of the 48 patients appeared to have a SAN that underwent degeneration during the study. We think that euthyroid patients with SAN may be managed under most circumstances by periodic follow-up examinations and that they need to be subjected to surgical or radioactive iodine therapy only when and if they subsequently develop hyperthyroidism.

Matched groups of ICR conventional (Conv) and germfree (GF) mice received neutron-gamma irradiation of 375 or 1000 rads, causing lesions in the small intestine. These developed faster in Conv than ...