Millard N. Croll

Clinical Evaluation of Lymph Node Scanning Utilizing Colloidal Gold 198

Radioactive colloidal gold 198, when injected intravenously, is localized within the reticuloendothelial system in the liver, spleen, and bone marrow. When injected in the intradermal and subcutaneous tissues, on the other hand, it flows through the lymphatic channels to the regional lymph nodes. The localization of the colloidal particles of gold 198 in the lymph nodes depends on the lymph node integrity and the patency of the lymphatic channels. The flow of the radioactive colloid through the lymphatics may be blocked by lymph nodes that are invaded or replaced by tumor. The diagnostic potential of colloidal gold 198 for the investigation of the lymphatic system has been explored by Hultborn et al. (3), Seaman et al. (8), Hahn and Carothers (2), and Sherman et al. (9, 10). The initial reports dealt not only with the distribution of the colloid in the regional lymph nodes when injected in the breast or in the calf region but also with its potential therapeutic efficacy in the treatment of lymph nodes inv...

The effect of experimental hypothyroidism on coronary blood flow and hemodynamic factors

A reduction in the basal metabolism rate and protein bound iodine conversion ratio in a group of dogs following the administration of I131 was accepted as evidence of experimentally induced hypothyroidism. Observations of cardiac functions were made in the normal control group and in the hypothyroid group. The latter group was characterized by a reduction in coronary sinus blood flow, left ventricular oxygen consumption and heart rate. Atropine increased each of these values in the hypothyroid animals to a level approximately equal to that induced by atropine in the normal control group. The ability of the hypothyroid heart to raise coronary sinus blood flow and left ventricular oxygen consumption to the level of the normal heart in response to atropine is explained in terms of changes in heart rate because a close association between heart rate and these two functions has been established under a wide variety of experimental conditions. The capacity of the hypothyroid heart to change its rate appears to be unimpaired. The cardiac index of the hypothyroid heart is also reduced but fails to return to the normal control levels in response to atropine. This reduction is probably associated with an increase in A-V oxygen difference, indicating a relatively greater reduction in cardiac output than in total oxygen consumption.

Intracavitary uses of colloids

Pleural and peritoneal effusion secondary to primary malignancy is a significant problem in the management of the cancer patient. Respiratory embarrassment and discomfort associated with the formation and collection of fluid in the chest and abdomen are among the most distressing symptoms encountered as a result of malignant disease. The guidelines for treatment should be based on respiratory symptoms, and with the understanding that the procedure is palliative. Both surgical and medical forms of treatment have been used. These include thoracostomy-tube drainage alone or with the instillation of antimicrobial agents. Pleurectomy is effective but should be reserved for situations in which conservative approaches have failed. Antitumor agents, such as nitrogen mustard, are effective but toxic. The mode of action of antineoplastic agents is related to their ability to cause pleural sclerosis and obliterate the pleural space. Systemic chemotherapy and external beam radiation are rarely effective. The intracavitary application of radioactive colloids has been used since 1945. Colloidal radioactive gold Au 198 has been replaced by the pure beta emitter, colloidal chromic phosphate P 32. Instillation of a colloidal suspension of radioactive phosphorus represents a significant and effective palliative therapeutic modality for malignant effusion.

Zinc-65 Uptake by the Prostate

Dogs were injected intravenously with 40 to 150 mu C Zn/sup 65/, with and without injections of testosterone, and prostatic radioactivity was followed by external scintiscanning and tissue analyses. The results revealed that dog prostate concentrates Zn/sup 65/ and maintains a significant level 7 to 9 days following intravenous injection of the isotope. The preparation of dogs with testosterone alone or in conjunction with pilocarpine did not significantly alter the concentration of Zn/sup 65/ by the prostate. With external scintiscanning techniques no selective differentiation could be made between the prostate and surrounding tissue. There was no discernible pattern in the distribution of Zn/ sup 65/ throughout prostatic tissue as measured by radioassay of serial tissue slices, by radioautography, or by in vitro scintiscanning of the whole gland or serial slices. Also, there was no difference in the Zn/sup 65/ uptake by prostate gland whether the carrier was ZnCl/sub 2/ or Zn aluconate. (P.C.H.)

Effects of hypoxemia on coronary blood flow and cardiac output in normal and hypothyroid dogs.

Abstract Simultaneous determinations of coronary blood flow by the nitrous oxide desaturation method and of cardiac output by the direct Fick arteriovenous oxygen difference method were made on dogs breathing 100%, 10% and 5% oxygen-nitrogen mixtures under morphine chloralose anesthesia. The observations were repeated with 100% oxygen and 10% oxygen- 90% nitrogen mixtures after a hypothyroid state had been induced by administration of 35 mc. of I 131 . Parallel increases in coronary blood flow and cardiac index occurred in the normal dog with progressive hypoxcmia. In the hypothyroid dog the cardiac index did not change significantly, and the increase in coronary blood flow was only about 50 per cent of the value observed in the normal group. The failure of the hypothyroid dog to demonstrate an increased cardiac index in response to hypoxemia is attributed to the removal of the potentiating action of the thyroid hormones upon the catecholamines of the sympathoadrenal system. The reduced but still significant increase in coronary blood flow in the hypothyroid group is brought about by hypoxic stimuli that act independently of hormonal influences.

Correlation of 198Au Abdominal Lymph Scans with Lymphangiograms and Lymph Node Biopsies

Abstract A retrospective study was undertaken to determine the correlation between lymph node scan findings and biopsy or lymphangiographic findings. There was good agreement between the lymph scan, lymphangiogram, and biopsy in cases of lymphomatous disease. Correlation between studies in cases of testicular neoplasm was significant, however, the number of cases was small. Poor correlation between studies was seen in cases of carcinoma of the cervix and a group designated as miscellaneous. Except in cases of lymphomatous disease, the use of lymph scanning is not recommended except where there is contraindication to lymphangiography.

A NEW AGENT FOR SPLENIC SCANNING: BMHP.

All Scintillation scanning technics depend upon a physiological concentrating mechanism of the administered radioisotope within the organ to be surveyed. It is only relatively recently that visualization of the spleen has been reported (5). This has been accomplished by various methods modifying red blood cells labeled with radioactive chromium 51 to promote their rapid selective sequestration from the circulation, primarily within the functioning spleen (2). Although at times successful, these methods have generally yielded scans of poor diagnostic quality, related to the radioisotope employed and to the erratic nature of sequestration of the altered red cells. The search for better agents for splenic scanning has continued. In 1957, Kessler, Lozano, and Pitts (1) found 1-iodo-mercuri-2-hydroxypropane concentrated in the spleen of dogs following intravenous injection. This discovery was not utilized until 1963 when Wagner (3) postulated that the splenic concentration might result from sequestration of re...

Evaluation of Calcium 47 in Normal Man and Its Use in the Evaluation of Bone Healing Following Radiation Therapy in Metastatic Disease

The use of external counting technics for the study of problems in bone metabolism has been hampered in the past by the lack of suitable isotopes. Many radioactive compounds have been utilized in the study of bone metabolism, but without great success. These have included gallium 72 (3, 4) sodium 22, sodium 24, barium 140, etc. Dudley et. al (5) are presently working with radioactive yttrium in this study. Bauer and his associates (1) introduced calcium 47 as an agent for the evaluation of bone metabolism. The radioactive calcium was found to be selectively localized in areas of osteoblastic activities such as the epiphyses in young persons, healing fractures, metastatic areas of carcinoma to bone, eosinophilic granulomas, osteomyelitis, chondromas, etc. Radioactive calcium 47 has a half-life of 4.7 days and emits a high-energy gamma ray of 1.3 Mev as well as a beta particle in its decay to scandium 47. Scandium 47 is also radioactive with a half-life of 3.8 days, and decays by the emission of a beta part...

Implications of lymphoscintigraphy in oncologic practice:Principles and differences vis-a-vis other imaging modalities

The prompt availability of interstitial lymphoscintigraphy and its utilization offer significant advantages over other techniques. Computed tomography represents a highly sensitive technique that suffers from lack of specificity in detecting small lesions. The expense and accessibility of machine time limit its usefulness as a routine survey procedure. Radiographic lymphangiography represents a tedious and difficult process necessitating identification of lymphatic channels for injection of the contrast material for visualization of the lymph nodes in the region being evaluated. With these demonstrated difficulties, the lymph node scanning technique has emerged as a simple, reliable, and reproducible technique for evaluation of multiple lymph node groups.

Clinical uses of bone scanning

The skeleton is a frequent site of metastatic disease. Radiographic examination is not sufficiently reliable in early detection since an abnormality is unlikely to be observed until more than 50% of the bone material has been lost. Therefore, skeletal scanning represents a viable technique for demonstration of dynamic response of bone to tumor invasion. This technique provides a more sensitive method for detection of early skeletal metastatic disease. Technetium 99m labeled methylenediphosphonate seems to be the best technetium 99m labeled agent for skeletal images, although ethyline hydroxydiphosphonate may be equally good. The toxicity of the compounds is low and repetitive studies can be done for continued clinical evaluation of the patient without significant risk.