PubMed Health⌕ Search

Biomedical subjects

H J Dworkin

Publications and source records attributed to H J Dworkin.

At least 37 records · Page 2Linked to original sources
PubMed1993

Unexpected pulmonary clumping of In-111 leukocytes attributable to indium oxine reagent.

Five cases of artifactual In-111 leukocyte pulmonary activity were noted at three local hospitals in a 4-day period. Based on the differences in the preparation of the final indium leukocyte product, the problem could be attributed to the indium oxine reagent in a specific lot. This artifact of multiple small foci of marked increased activity in the lungs (clumping pattern), attributable to the In-111 oxine reagent, has not been described previously.

Aged↗
PubMed1993

Comparison of personnel radiation dosimetry from myocardial perfusion scintigraphy: technetium-99m-sestamibi versus thallium-201.

The whole-body and hand radiation doses to our technical staff were retrospectively compared for three distinct 4-mo periods when either 201TI or 99mTc-sestamibi were exclusively used for stress myocardial perfusion imaging. During the initial 4-mo period when 99mTc-sestamibi replaced 201TI, the mean whole-body film badge readings increased from 100 to 450 microSv/mo (p < 0.001) for nuclear medicine technologists (n = 10) and from 240 to 560 microSv/mo (p < 0.05) for radiopharmacy technologists (n = 2). Mean TLD readings to the hands also increased, although the differences were not statistically significant for the nuclear medicine technologists. Noninvasive cardiology staff were monitored with film badges and the mean whole-body film badge reading, when 99mTc-sestamibi was the imaging agent, was 360 microSv per month. Radiation reduction methods that decreased radiation exposure to staff were utilized. The most effective included the use of a lead face shield and lead lined storage container in the noninvasive imaging area, handling spills by shielding instead of decontamination and methods to reduce time spent in close proximity to the patient.

Film Dosimetry↗
PubMed1992

Radiation safety considerations for post-iodine-131 thyroid cancer therapy.

The purpose of this study was to develop guidelines based on direct patient measurements as to when 131I-treated thyroid cancer patients may resume close personal contact after release from the hospital. External exposure rates were measured on 27 patients using a calibrated ionization survey meter. The patients' exposure rates were measured at the time of release from the hospital and 2-7 days post-hospital discharge. Measurements were taken at 1, 0.6 and 0.3 meters from the patient's upright body axis (stomach to thyroid). Vertical movement of the survey instrument was utilized to obtain the maximum reading each time. All patients had exposure rates less than 2 mR/hr at 1 meter at 2-4 days post-hospital discharge. Eight-eight percent (21/24) had exposure rates less than 2 mR/hr at 0.6 meter at 2-4 days post-hospital discharge. Guidelines can be prepared specifically for thyroid cancer therapy patients that are rational and consistent with existing radiologic health standards.

Adult↗
PubMed1991

Radiation safety considerations for post-iodine-131 hyperthyroid therapy.

The purpose of this study was to develop guidelines based on patient measurements as to when iodine-131- (131I) treated hyperthyroid patients may resume close personal contact. External exposure rates were measured on 59 patients using an ionization survey meter in the upright position. The initial measurement was recorded within 20 min post-dose administration at one meter. Exposure rates were measured 2-11 days post-dose administration at 1, 0.6, and 0.3 meters from the patient's thyroid. In the administered dose range of 3 to less than 12 mCi of 131I, all 40 patients measured less than or equal to 2.0 mR/hr at one meter on Day 0, and 25 patients (25/29) were less than or equal to 2.0 mR/hr at 0.6 meter on Days 2-4. Guidelines can be prepared based on the administered dose that are rational and in conformity with existing radiologic health standards.

Breast Feeding↗
PubMed1989

Splenic imaging in a patient with functional asplenia.

A 65-year-old woman presented with right upper extremity paralysis and left cerebrovascular accident. A routine complete blood count (CBC) demonstrated Howell-Jolly bodies on peripheral smear, and a liver-spleen scan showed absent splenic sulfur colloid uptake suggesting functional asplenia. A subsequent heat damaged red blood cell study demonstrated a normal sized spleen with preserved sequestering function, thereby excluding anatomic asplenia, vascular alterations, or congenital anomalies in the differential diagnosis of functional asplenia. This case illustrates the use of Tc-99m heat damaged red blood cells as a unique and useful diagnostic aid in identifying the presence and size of a spleen in patients with functional asplenia. It also demonstrates an apparent qualitative separation of splenic functions in processing sulfur colloid and heat damaged red blood cells.

Aged↗
PubMed1989

Phantom feet on digital radionuclide images and other scary computer tales.

Malfunction of a computer-assisted digital gamma camera is reported. Despite what appeared to be adequate acceptance testing, an error in the system gave rise to switching of images and identification text. A suggestion is made for using a hot marker, which would avoid the potential error of misinterpretation of patient images.

Aged↗
PubMed1983

Cholescintigraphy in cholecystic cancer.

Two case reports of nonvisualization of the gallbladder by hepatobiliary scintigraphy in patients with carcinoma of the gallbladder are described. A hypothesis regarding the pathogenesis of gallbladder nonvisualization in cholecystic cancer is offered. The possible clinical utility of hepatobiliary scintigraphy in these patients is discussed.

Adenocarcinoma↗
PubMed1983

Acid-citrate-dextrose compared with heparin in the preparation of in vivo/in vitro technetium-99m red blood cells.

Red blood cells labeled in vivo/in vitro with Tc-99m (Tc-99m RBC) were prepared in a series of 21 patients and two normal volunteers. In each subject both heparin and acid-citrate-dextrose (ACD) solutions were used to label tandem blood samples. The immediate preinjection binding efficiency (BE) was then determined. In each of the 23 studies, the ACD preparation yielded superior BE. The average BE was 93.47% (+/- 3.78) with ACD and 87.23% (+/- 4.29) with heparin. With the ACD method the effect of carrier Tc-99 may be as great as a 24% reduction in BE observed when initial eluates from long-ingrowth-time generators were used. Improved image quality with minimal renal and urinary-bladder activity results with ACD labeling. It is concluded that the use of ACD results in superior RBC labeling with less nontarget activity relative to heparin and is preferred over heparin for preparing in vivo/in vitro Tc-99m RBC.

Aged↗
PubMed1981

A method for the determination of ECG gate signal delays.

A simple device using a rotating radioactive source was developed to monitor the presence of a delay between the patient's R wave and the gate signal being sent to the computer. Three commercial ECG gates were tested and significant delays were found in two of them. Identical patient data evaluated using ECG gates with and without significant delays produced calculated left-ventricular ejection fractions of 0.05 and 0.64, respectively.

Computers↗
PubMed1977

The incidental detection of gallium-67 citrate in a urinoma following a right pyeloplasty: a case report.

An abnormal accumulation of radionuclide was identified within the right juxtadiaphragmatic and juxtahepatic spaces during gallium-67 citrate scintigraphy in a post-pyeloplasty patient. Its mode of presentation, the recent pyeloplasty and the known biologic distribution of gallium suggested that it represented gallium-67 concentration within a postoperatively created urinoma. Diagnosis was confirmed by excretory urography and laparotomy.

Adolescent↗
PubMed1977

Effect of particle number on lung perfusion images: concise communication.

Twelve normal mongrel dogs were injected with decreasing numbers of 99mTc-labeled macroaggreagated albumin particles (99mTc-MAA), and lung images were recorded using both parallel-hole and pinhole collimators. The quality of normal lung images was found to decrease with decreasing numbers of injected radiolabeled particles (from 10,000 to 250 particles per injection). The quality was unaffected by adding carrier MAA. The minimum number of particles compatible with a good-quality image of the normal human lung is approximately 60 radiolabeled particles per gram of lung.

Animals↗