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R J Lull

Publications and source records attributed to R J Lull.

At least 19 recordsLinked to original sources
PubMed1995

Feasibility of Meckel's scan after RBC gastrointestinal bleeding study using in-vitro labeling technique.

The authors report a successful Meckel's scan performed 26 hours after a labeled RBC study using a commercial in-vitro labeling kit, UltraTag (Mallinckrodt Medical, Inc., St. Louis, MO). No abnormal alteration of Tc-99m distribution was observed as would be seen if an in-vivo RBC labeling technique was used. This case demonstrates that it is feasible to perform an in-vitro labeled RBC study for acute gastrointestinal bleeding in pediatric patients and to follow-up with a Meckel's scan if it is necessary for diagnostic confirmation.

Child↗
PubMed1994

Technetium-99m-MDP uptake in thyroid cartilage in invasive squamous-cell laryngeal carcinoma.

A 36-yr-old male with a past history of invasive squamous-cell carcinoma of the larynx underwent 99mTc-MDP scintigraphy for the evaluation of lower back pain. The scan findings were unremarkable except for markedly and uniformly increased tracer uptake in the region of the thyroid cartilage, suggesting calcification and/or tumor invasion. Confirmation of significant pathology was obtained on tissue examination from a subsequent total laryngectomy demonstrating inflammatory infiltration and perichondrial invasion of the thyroid cartilage by carcinoma.

Adult↗
PubMed1994

A count-based radionuclide method for volume quantitation using conjugate imaging and an external reference source: theoretical consideration and phantom study.

UNLABELLED: A count-based method was developed for ventricular volume determination during multigated equilibrium cardiac blood-pool imaging (MUGA). METHODS: Two sets of conjugate images of the volume were obtained, one with an external reference overlying the volume and the other without. The reference has known activity and dimension. The ratio of the geometric mean count rates over a pixel obtained from these two conjugate images, Ratio(geo), and the ratio of the specific activity in the reference to that in the volume, Ratio(ext), were used to calculate the length of the volume over that pixel perpendicular to the camera face, H, as a function of the length of the reference source, R, and the attenuation coefficient, ub, of the volume: [formula: see text] Based on H, the volume is then calculated. This method corrects for attenuation directly and determines the volume explicitly. To validate this method, phantom studies are carried out with known volumes of 99mTc containing saline solutions in situations of variable amount of attenuating medium and background activity. RESULTS: In all cases, the calculated volume agrees closely with the actual volume. CONCLUSION: This is an accurate method of volume quantitation that is well suited for determining ventricular volume during MUGA studies.

Cardiac Volume↗
PubMed1993

Work force problems in nuclear medicine and possible solutions.

Nuclear medicine practice and work force demographics reflect the historically diverse evolution of this specialty. The most pressing problem for nuclear medicine is a projected shortage of fully trained physicians due to practitioner retirement that is unmatched by residency program output. During the past decade the number of 2-year nuclear medicine residency programs (average of 90) and the total number of residents (average of 191 in both years) have remained remarkably stable. In contrast, the number of 1-year nuclear radiology residency programs, available positions, and residents have declined significantly. A similar decline is seen in radiologists obtaining full nuclear medicine training and American Board of Nuclear Medicine (ABNM) board certification. This void has been filled by nonradiologist trainees who only seek certification by ABNM. Perhaps such shifts in resident profile are an early indicator that the United States is evolving toward practice models in which nuclear medicine is provided by fully trained, full-time physicians, similar to the European work force model. The recent Society of Nuclear Medicine survey of 10,446 physicians who practice nuclear medicine shows a current practice pattern in the United States that is distinctly different from that in Europe. The vast majority of those surveyed practice part time. Only 7% of all physicians who practice nuclear medicine do so full time, (ie more than 90% of the time), but they account for as much full-time employee (FTE) work load as 70% of all part-time physicians. Although the number of radiologists entering nuclear medicine is declining, 51% of total FTE work load is still done by radiologists with only American Board of Radiology certification. Physicians certified by ABNM represent 42% of all FTE work load. Cardiologists certified by American Board of Internal Medicine-Cardiovascular Specialization account for approximately 4% of nuclear medicine (15% of total cardiovascular nuclear medicine) FTE work load. Work force shortage of nuclear medicine technologists remains a chronic problem in spite of extensive study: however, recent predictions suggest some improvement in the future. Solutions to work force problems facing nuclear medicine will require ongoing data surveys, aggressive recruitment of trainees, expansion of training positions, and socioeconomic initiatives that promote desirable future practice models.

Adult↗
PubMed1992

Tc-99m sestamibi myocardial imaging at rest for evaluation of cocaine-induced myocardial ischemia and infarction.

Many clinical cases of cocaine-induced myocardial infarction have been reported in the literature. Of the reported cases, patients tend to be young (in the third decade of life), chronic abusers with myocardial infarction typically involving the anterior left ventricular wall. This case report demonstrates the usefulness of two-phase (symptomatic and asymptomatic) Tc-99m sestamibi myocardial imaging at rest for definitive diagnosis of cocaine-induced myocardial ischemia and infarction.

Adult↗
PubMed1986

Asymptomatic total hip prosthesis: natural history determined using Tc-99m MDP bone scans.

A prospective study was performed with 97 patients who had undergone total hip replacement surgery and who were not experiencing pain or other symptoms or problems. The study was intended to determine the normal postoperative appearance of radionuclide scans of the hip following administration of technetium-99m methylene diphosphonate. Five areas of the prostheses were evaluated. Results showed that 6 months after implantation activity around the lesser trochanter and prosthesis shaft became insignificant. Activity around the acetabulum, greater trochanter, and prosthesis tip stabilized approximately 2 years after surgery; approximately 10% of patients in the study had persistent activity in these areas. Familiarity with this normal progression is fundamental to interpretation of postoperative bone scans in patients with total hip prosthesis.

Acetabulum↗
PubMed1985

Localization of lower gastrointestinal hemorrhage. Experience with red blood cells labeled in vitro with technetium Tc 99m.

Seventy-six patients clinically suspected of having lower gastrointestinal bleeding were studied by scintigraphy utilizing red blood cells labeled in vitro with technetium Tc 99m. Sixteen patients required emergency surgery; bleeding was accurately localized in 15 (94%). One patient (6%) had a normal scan. A 20-month mean follow-up of the 16 patients showed no recurrent bleeding. Of 60 patients not requiring emergency surgery, bleeding was localized in 11, but the bleeding ceased. Forty-nine of the 60 patients had normal scans and had no further hemorrhaging during hospitalization. A 21-month mean follow-up of 38 of the 49 patients showed no further bleeding episodes or surgical procedures in 29 patients; however, eight patients required surgical procedures, including seven for gastrointestinal malignancies. Scanning of red blood cells labeled in vitro with 99mTc is accurate and efficacious in localization of bleeding sites that require emergency surgery for lower gastrointestinal hemorrhage.

Adult↗
PubMed1984

Scintigraphy of gastrointestinal hemorrhage: superiority of 99mTc red blood cells over 99mTc sulfur colloid.

The relative efficacy of 99mTc sulfur colloid and in vitro-labeled 99mTc red blood cells in detecting and localizing gastrointestinal hemorrhage was evaluated in a prospective tandem study of 100 patients referred for suspicion of gastrointestinal tract hemorrhage. Thirty-eight true-positive scintigrams were obtained with 99mTc red blood cells, whereas 99mTc sulfur colloid detected only five sites of hemorrhage. Scintigraphic findings were corroborated by clinical, endoscopic, arteriographic, and surgical findings. 99mTc red blood cells were clearly superior, with a sensitivity of 93%, specificity of 95%, and overall accuracy of 94% in detecting and localizing gastrointestinal hemorrhage.

Adolescent↗
PubMed1983

Increased left ventricular ejection fraction after a meal: potential source of error in performance of radionuclide angiography.

The effect of a standardized meal on left ventricular (LV) ejection fraction (EF) was determined by equilibrium radionuclide angiography in 16 patients with stable congestive heart failure but without pulmonary or valvular heart disease. LVEF was determined in the fasting state and 15, 30, and 45 minutes after a meal. Patients with moderately depressed fasting LVEF (30 to 50%), Group I, had a mean increase of 6.9 +/- 2.9% (p less than 0.005) in the LVEF at 45 minutes after the meal. Patients with severely depressed fasting LVEF (less than 30%), Group II, had no change after the meal. It is concluded that significant increases in LVEF may occur after meals in patients with moderate but not severe left ventricular dysfunction. Equilibrium radionuclide angiography studies that are not standardized for patients' mealtimes may introduce an important unmeasured variable that will affect the validity of data in serial studies of left ventricular function.

Adult↗
PubMed1983

Radionuclide evaluation of lung trauma.

Nuclear medicine imaging procedures can play a significant role in evaluating the pulmonary complications that are seen in trauma patients. A quantitative method for measuring increased pulmonary capillary permeability that uses Tc-99m HSA allows early diagnosis of acute respiratory distress syndrome (ARDS) and accurately differentiates this condition from pneumonia or cardiogenic pulmonary edema. This technique may be of great value in following the response to therapy. The use of 133Xe to diagnose inhalation injury remains an important diagnostic tool, particularly at hospitals with specialized burn units. Regional decreases in ventilation-perfusion images reliably localize aspirated foreign bodies. Radionuclide techniques that are used to demonstrate gastropulmonary aspiration remain controversial and require further clinical evaluation. Pulmonary perfusion imaging, although nonspecific, may provide the earliest clue for correct diagnosis of fat embolism, air embolism, contusion, or laceration. Furthermore, the possibility of perfusion abnormality due to these uncommon conditions must be remembered whenever trauma patients are evaluated for pulmonary thromboembolism with scintigraphy. Occasionally, liver or spleen scintigraphy may be the most appropriate procedure when penetrating chest trauma also involves these subdiaphragmatic organs.

Adolescent↗
PubMed1983

Scintigraphic detection of occult hemorrhage using RBCs labeled in vitro with technetium Tc 99m sodium pertechnetate.

Scintigraphy with RBCs labeled with technetium Tc 99m sodium pertechnetate effectively located the source of hemorrhage in a patient receiving long-term anticoagulant therapy. (The patient was initially seen with a large hematoma on the flank.) More important, the procedure was used to monitor activity in this otherwise-occult bleeding site. Scintigraphic studies may be useful in the management of these difficult clinical problems.

Aged↗