This Article Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints, Permissions and Rights Citing Articles Citing Articles via Google Scholar Google Scholar Articles by ALLEN, H. C. Articles by GREENE, J. A. Search for Related Content PubMed PubMed Citation Articles by ALLEN, H. C., JR. Articles by GREENE, J. A.

OBSERVATIONS ON THE NODULAR THYROID GLAND WITH THE GAMMAGRAPH^*

Radioisotope Unit, Veterans Administration Hospital, Houston, Texas, and the Department of Medicine, Baylor University College of Medicine Houston, Texas

THE introduction of the scintillation counter (1, 2, 3, 4) to clinical medicine, as a possible replacement for the less-sensitive gammadetecting Geiger-Mueller counter for in vivo studies in human beings, has led to many interesting observations and has suggested several new applications of radiotracers. Because of the increased efficiency of the scintillation counter for gamma radiation, it became possible to construct a specially designed gamma-detecting scintillation counter with an optical geometry whose resolution is such that the isotope-concentrating tissue can be outlined in such a manner that a silhouette indicating the size and shape of the tissue can readily be obtained. The silhouette of the isotope-concentrating tissue, for the sake of simplicity and clarity, has been designated a gammagram, so named because the principle of its production is similar to the principle involved in making a photograph. Instead of an image created by photons of visible light, a gammagram represents an image created by photons of gamma rays as recorded by means of an automatic scanning device, utilizing a calcium tungstate scintillation counter as a detector or "camera." Thus it is possible to "photograph" or gammagraph any gamma-emitting, isotope-concentrating tissue located beneath the surface of the body. The automatic scanner or gammagraph used in these studies represents a refinement of the manual scanner presented in 1950 (5).

^* Read at the Annual Meeting of the American Goiter Association, St. Louis, Missouri, May 1–3, 1952.

This article will be included in the bound volume of the 1952 "Transactions of the American Goiter Association" published by Charles C Thomas, Publisher, which will be available for sale early in 1953.

Received May 17, 1952.