I. Meschan

Value of the Routine Use of the Cerebral Dynamic Radioisotope Study

Abstract The results of 1,165 serial dynamic studies were reviewed. The routine addition of the dynamic study to the static image increased the detection of lesions by 33%. In patients with middle cerebral or carotid disease, the number of abnormal studies was doubled. Meningioma, arteriovenous malformation, and middle-cerebral-artery occlusion produced characteristic patterns on the dynamic study. Specific combinations of dynamic study and static image findings increased the certainty of diagnosis. Decreased perfusion was due to cerebrovascular disease eight times more often than to tumor. The combination of normal perfusion and a positive gamma camera image occurred three times as frequently with tumor as with cerebrovascular disease.

The utilization of radioactive zinc and manganese in an effort to visualize the pancreas.

From time to time various substances have been shown to concentrate selectively in the pancreas, but thus far no useful nonsurgical means for pancreatic visualization for clinical study has been demonstrated. In 1929, Crandall, Oldberg, and Ivy reported on a large number of dyes which concentrated moderately selectively in the pancreas, but at that time they could foresee no useful clinical test which might be derived from these studies (1). In 1943, Sheline et al. (2) studied the distribution of radioactive zinc administered to mice and dogs and found it in highest concentration in the pancreas with considerable amounts also in the liver and kidneys. The zinc content in the pancreas was thought to be many times that necessary to account for its insulin content in the form of a zinc salt. In another study, Montgomery, She-line and Chaikoff (3) showed the maximum amount of zinc 65 in the whole pancreas to be 3.1 per cent at eight hours. By the fourteenth day a large proportion had been excreted into the pa...

The Utilization of Radioactive Iodinated Hippuran for Determination of Renal Clearance Rates

Radioactive tagging of chemicals has given the investigator a means of simplifying tests for many physiologic functions. Quantitative assays of renal function hitherto have been cumbersome, and to some degree hazardous, in view of the possible introduction of infection if bladder catheterization must be employed. Yet greater accuracy in the study of split renal function is now more important than ever, with the increased interest in surgical corrective measures, particularly for renovascular hypertension. With these considerations, a study was undertaken with the following objectives: (a)To determine whether or not a radioactive clearance study technic could be developed which would parallel standard technics. (b)To determine whether or not such a technic could be adapted to human use without subjecting the patient to excessive radiation from large amounts of the labeled compound. (c)To simplify the basic technic to a single intravenous injection, with avoidance of catheterization through the use of exter...

The Utilization of I131-Labeled Renografin as an Inulin Substitute for Renal Clearance Rate Determination1

Our previous report (1) described a technic for I131 ortho-iodo-hippuric acid (OIHA) renal clearance rate determination following a single injection of this compound and utilizing a modification of the classical Homer Smith clearance procedure (2). The OIHA clearance ratio to simultaneous para-aminohippurate clearance (PAH), varied between 0.6 and 0.8. The results were reasonably consistent on repeated examination of a given unanesthetized animal and hence probably utilizable for estimating renal tubular function and effective renal plasma flow. Due to the relatively low OIHA∕PAH ratio (0.6 to 0.8), however, a substitute for PAH giving a higher ratio than the OI131HA could be expected to give better results. It has further been our purpose to attempt to develop a radioactive technic which would parallel the inulin clearance rate. This has posed considerable difficulty because of our inability to achieve a gamma-labeled compound chemically similar to inulin. On the basis of the fact that OI131HA is handled...

A Method and Parameters for the Analysis of Renal Function by External Scintillation Detector Technic

The iodopyracet renogram (i.e., the graphic record of kidney excretion) has been a useful clinical tool, but its utility in evaluation of renal function is limited because of hepatic interference. With the advent of more selective agents, as ortho-iodohippuric acid I131 (OIHA)2, hepatic uptake has been minimized (1). It is now possible to compare right and left renal curves with greater confidence, and theoretically to produce quantitative values related to renal function. With such values it should be possible to define limits of normal function. Methods of Renogram Analysis The analysis of the renogram can be approached in four possible ways: I. A Visual Comparison of the Curves: In this method the curves are compared as to height and shape by observation. The advantage of the method is that the analysis can be completed quickly and requires only a trained interpreter. The disadvantages are: (a) that a rather broad experience in renogram interpretation is required; (b) that interpretation is difficult w...

The Radiologic Diagnosis of Renovascular Hypertension

Renovascular hyper tension may be defined as systemic hypertension produced by pathologic changes in the renal vascular tree. It has been demonstrated that this phenomenon is not always dependent on renal ischemia but may be on the basis of subtle pressure-flow differences between the renal vascular bed and the aorta. This etiology has been estimated to account for from 1 to 20 per cent of the hypertensive population (1, 2). History, physical examination, and splitfunction studies have proved helpful in the recognition of renovascular hypertension (3, 4). Here we will present and discuss the radiologic aids which are useful in its diagnosis and management, viz., the intravenous pyelogram (I.V.P.), the radioisotopic renogram, and the renal arteriogram. The Intravenous Pyelogram Other workers have employed the intravenous pyelogram in the diagnosis of renovascular hypertension with varying success (5–7). Radiographic abnormalities which we have encountered that are suggestive of the diagnosis of renovascula...

Convulsive fractures of the dorsal spine following electric-shock therapy.

Although fractures of the dorsal spine following convulsive seizures of tetanus have been known since 1907 (1) and a great number of publications regarding metrazol fractures have appeared since 1938 (2), relatively little has appeared in the English and American literature regarding spine fractures resulting from electricshock therapy. In 1942, Worthing and Kalinowsky (3) reported, on the basis of their private communications with many clinics which at that time were using electric-shock therapy, that electric convulsive fractures were about one-fourth as frequent as metrazol fractures. The incidence of fractures in their own series of cases was 10 per cent. Barrett, Funkhouser, and Barker (4) thereafter studied twenty selected cases each, associated with electric shock, metrazol therapy, and epilepsy and twenty cases in non-convulsive patients, and indicated that the fractures in these four groups looked very much alike. In 1946, Huddleson and Gordon (5) reported briefly a survey of 252 patients who wer...

Newer methods of pneumoarthrography of the knee with an evaluation of the procedure in 315 operated cases.

Introduction The earliest recorded use of pneumoarthrography of the knee was made by Werndorff and Robinson (1) in 1904, and although numerous studies of the method have been made since that time, it has not achieved widespread popularity as a diagnostic procedure, for several reasons: In the first place, the method requires extensive experience so that a good technic may be developed and film studies can be accurately interpreted. Most reported series of cases in this country have been small, and the accumulated experience of any one man has been limited. In the second place, there has been some misunderstanding regarding the inherent danger of the method. Kleinberg (2) has reported the occurrence of air embolus, but in that instance adequate precautions were not taken to make certain that the needle was not in a blood vessel. Actually, this danger is inherent in any subcutaneous or intramuscular injection if such precautions are neglected. In over 800 pneumoarthrographic studies we have had not a single...

The Usefulness of the Radioisotopic Renogram in Radiation Therapy

The purpose of the present investigation was to assess the usefulness of the radioisotopic renogram in detecting early changes in the urinary tract in patients undergoing radiation therapy to the pelvis and abdomen. This was done by comparing the renogram with conventional intravenous pyelograms and by obtaining these studies serially to determine changes during and after a course of irradiation. Method And Materials The radioisotopic renogram was obtained in the following way: 1. Matched one-inch sodium iodide crystal scintillation probes were placed over the kidneys posteriorly. 2. Iodine-LSI orthoiodohip-puric acid,2 0.5 microcuries per kilogram, was injected intravenously. 3. The initial vascular phase was recorded in rectilinear fashion at a chart speed of 12 in./min. with abdominal-aorta monitoring as a third probe. 4. After the vascular phase reached a plateau, the secretory and excretory phases were recorded at a slower speed, 12 in./hr. 5. The half-time values for each of these periods was determ...

Statistical Relationship of Brain Scans, Cervicocranial Dynamic Studies, and Cerebral Arteriograms

The authors compared rapid sequence cervicocranial camera images, scans, angiograms, and pneumograms in 146 cases of neurological disorder. It was found that use of imaging is justified as a screening procedure prior to performance of routine radionuclide brain scanning. Further information is offered in a significant number of cases, particularly when this single study is compared with information obtained by cerebral angiography and pneumography. Additionally, the rapid sequence images, when studied with the brain scans, may help establish such diagnoses as arteriovenous malformation, tumor, or infarction.