Martin L. Nusynowitz

Consensus recommendations for gastric emptying scintigraphy: A joint report of the American neurogastroenterology and motility society and the society of nuclear medicine

This consensus statement from the members of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine recommends a standardized method for measuring gastric emptying (GE) by scintigraphy. A low-fat, egg-white meal with imaging at 0, 1, 2, and 4 h after meal ingestion, as described by a published multicenter protocol, provides standardized information about normal and delayed GE. Adoption of this standardized protocol will resolve the lack of uniformity of testing, add reliability and credibility to the results, and improve the clinical utility of the GE test.

Consensus Recommendations for Gastric Emptying Scintigraphy: A Joint Report of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine

This consensus statement from the members of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine recommends a standardized method for measuring gastric emptying (GE) by scintigraphy. A low-fat, egg-white meal with imaging at 0, 1, 2, and 4 h after meal ingestion, as described by a published multicenter protocol, provides standardized information about normal and delayed GE. Adoption of this standardized protocol will resolve the lack of uniformity of testing, add reliability and credibility to the results, and improve the clinical utility of the GE test.

Long-term reduction in bone mass after severe burn injury in children.

OBJECTIVEnBecause burn victims are at risk of having bone loss, a cross-sectional study was undertaken to determine whether severe burn injury had acute and long-term effects on bone mass or on the incidence of fractures in children.nnnMETHODSnDual-energy x-ray absorptiometry of the lumbar portion of the spine was performed on 68 children: 16 moderately burned (15% to 36% of total body surface area) and 52 age-matched severely burned (> or = 40% of total body surface area). Twenty-two severely burned children were hospitalized and studied within 8 weeks of their burn, and 30 others were studied approximately 5 years after discharge. In the severely burned group, both hospitalized and discharged, serum and urine were analyzed for calcium, phosphorus, intact parathyroid hormone, osteocalcin, and type I collagen telopeptide.nnnRESULTSnSixty percent of severely burned patients had age-related z scores for bone density less than -1, and 27% of severely burned patients had age-related z scores for bone density less than -2 (p < 0.005, for each). In the moderately burned group, 31% of patients had z scores less than -1 (p < 0.005 vs normal distribution), but only 6% had z scores less than -2 (p value not significant). There was evidence of increased incidence of fractures after discharge in the severely burned patients. Biochemical studies were compatible with a reduction in bone formation and an increase in resorption initially, and with a long-term persistence of low formation.nnnCONCLUSIONnWe conclude that acute burn injury leads to profound and long-term bone loss, which may adversely affect peak bone mass accumulation.

Spinal-cerebrospinal fluid leak demonstrated by radiopharmaceutical cisternography

Cerebrospinal fluid (CSF) leaks are known to occur under several conditions: lumbar puncture performed for contrast myelography, spinal surgery, spinal stab wounds, fracture of the thoracic spine, inadvertent spinal puncture during epidural anesthesia, traumatic lumbar meningocele, and bronchopleural subarachnoid fistula due to bronchogenic carcinoma. Spontaneous spinal leaks are uncommonly encountered in neurosurgical practice, but they are increasingly recognized as a cause of spontaneous intracranial hypotension. Most CSF leaks are located at the cervicothoracic junction or in the thoracic spine. The disease is often self-limiting. A CSF leak can be detected directly by accumulation of radioactivity outside the subarachnoid space or suggested indirectly by the rapid disappearance of tracer from the subarachnoid space and early appearance in the urinary bladder. In this paper we present two unusual cases of CSF leak identified by radiopharmaceutical cisternogram.

Is there a thyrotoxic cardiomyopathy in children

We measured left ventricular ejection fraction by radionuclide angiocardiography at rest and during graded exercise in eight thyrotoxic children. Five patients were reassessed after return to a clinically euthyroid state. In the thyrotoxic state the left ventricular ejection fraction was 69% +/- 8% at rest, and increased normally by 7% to 10% during exercise in four patients but did not change significantly or decreased by as much as 8% in the other four patients. The change in left ventricular ejection fraction during exercise correlated inversely with serum concentrations of thyroxine (r = -0.82, P less than 0.02) and triiodothyronine (r = -0.88, P less than 0.01). A comparison between patients who had normal left ventricular response to exercise with those who had abnormal response while thyrotoxic failed to uncover any significant differences between their resting ejection fractions or resting and exercise heart rates and systolic blood pressures. Three abnormal and two normal responders were reassessed after return to a clinically euthyroid state. The left ventricular ejection was 64% +/- 6% at rest, and increased during exercise in all patients. Our study suggests that thyrotoxicosis causes diminished left ventricular reserve (compensated functional cardiomyopathy) in some patients, but appears to be reversible. Severity of thyrotoxicosis, as measured by thyroid hormone blood levels, may be a determining factor in the development of functional cardiomyopathy.

What influences early hypothyroidism after radioiodine treatment for Graves' hyperthyroidism?

Objective: The objective of this study was to evaluate the factors influencing the occurrence of early hypothyroidism after radioiodine treatment of Graves hyperthyroidism. Material and Methods: Of 147 patients with Graves disease (GD) treated with radioactive I-131 (RAI) in our thyroid clinic between July 2003 and December 2004, 84 were followed at 2 and 4 to 5 months after treatment. The age range was 12 to 75 years and the dosage range in these patients was 7.4 to 29.9 mCi. Twenty-four were males and 60 were females. Factors possibly contributing to post-RAI hypothyroidism are: dosage of I-131, age, gender, size of the gland, initial serum free T4, free T3, thyroid-stimulating hormone (TSH) levels, pretreatment with antithyroid drugs, radioactive iodine uptake, and duration of disease. Results: All patients had low TSH, elevated FT4, and elevated radioactive iodine uptake (RAIU) at 4 and/or 24 hours. Of the 84 patients followed, 46% of the males and 62% of the females became hypothyroid at 4 to 5 months (57% of the total). Twenty-one patients remained hyperthyroid and 14 patients became euthyroid. Multivariate analysis of these 84 patients showed no statistically significant single contributing factor for the development of early hypothyroidism. Conclusion: The early onset of hypothyroidism after RAI in GD is very common (57%) and unpredictable. Thus, after RAI treatment, all patients must be closely monitored for the development of this disorder.

Population exposure from nuclear medicine procedures: measurement data

In order to estimate the public radiation burden from nuclear medicine studies, a TLD chip in a sealed plastic bag was taped on the abdomen of patients who received 111In as chloride or oxine, 201T1 chloride, or one of four common 99mTc agents. The TLD chip was removed after 24 h. Additionally, abdominal skin surface exposure rate measurements were performed with an ionization chamber survey meter at various times (0 to about 60 h). There was superb correlation between TLD and integrated exposure rate measurements and between TLD and ionization chamber measurements and MIRD calculated doses. Scenarios postulated for exposure of co-workers and family members yielded doses between 7 muSv (0.7 mrem) and 20 muSv (2 mrem) for the selected radiopharmaceuticals. Calculations of the total population exposure from nuclear medicine procedures indicate the per capita dose (amortized over the entire population) is approximately 0.4 muSv (0.04 mrem), a negligible dose compared to natural background and total medical irradiation.

Is silent ischemia on the routine admission ECG an important finding

The authors objective was to determine if, in the absence of known coronary artery disease, ST-T changes suggestive of silent ischemia on the admission electrocardiogram (ECG) identify a group of patients at high risk for cardiac event or death. A prospective cohort study was undertaken at the university hospital of a tertiary care center. All patients admitted to the hospital during the 5-month study period were screened. The authors found 54 patients with risk factors but no symptoms of coronary artery disease whose admission ECGs showed silent ischemia (ischemia group), and 71 patients with similar risk of coronary artery disease but without admission ECGs showing silent ischemia (control group). Three-week and 6-month incidences of angina, myocardial infarction, and death among patients in the silent ischemia and control groups were compared. Seven (13%) patients in the silent ischemia group had cardiac events or noncardiac death in the subsequent 3 weeks versus one (1%) noncardiac death in the control group (p < 0.02). At 6 months, eight (15%) patients in the silent ischemia group versus two (3%) in the control group had cardiac events (p = 0.02). It is concluded that among patients with risk factors but no symptoms of coronary artery disease, silent ischemia on the admission ECG is associated with an increased likelihood of short-term death or cardiac event.

Uptake of 131I-metaiodobenzylguanidine by 6–23 rat medullary thyroid carcinoma

Uptake of 131iodine-metaiodobenzylguanidine (131I-MIBG) by 6-23 rat medullary thyroid carcinoma (MTC), was studied in vitro and in vivo. In vitro, there was an 8-fold increase in 131I uptake by 6-23 cells when labeled with 131I-MIBG (131I 24 +/- 15 cpm/10(6) cells, 131I-MIBG 196 +/- 9 cpm/10(6) cells). MIBG uptake in vitro was the same at 4 degrees C and 37 degrees C. In contrast, 131I-MIBG uptake by PC-12 rat pheochromocytoma cells were 200 times greater (131I-MIBG 42,412 +/- 6,755 cpm/10(6) cells). 131I-MIBG uptake by rat MTC cells in vitro were of a comparable magnitude to the uptake of 131I-MIBG by rat ileal enterochromaffin cells (RIE-1) and mouse colon cancer cells (MC-26). In vivo, uptake of 131I-MIBG by 6-23 MTC tumor was considerably less than in the normal tissues (muscle, liver, spleen, kidney, adrenal and thyroid). Gamma camera studies of 131I-MIBG uptake by 6-23 MTC tumors growing in Wag-Rij rats were only transiently positive in 1 out of 4 rats studied. We conclude that 131I-MIBG is poorly taken up by rat medullary thyroid carcinoma and is an unpredictable marker for localization of rat MTC.

88 FUNCTIONAL THYROTOXIC CARDIOMYOPATHY IN CHILDREN

Myocardial performance during thyrotoxicosis (T) was evaluated by multigated radionuclide angiocardiography during graded axercise in 8 children (8-17 ys) with Graves disease. With exercise, heart rate (HR) and systolic blood pressure (SBP) increased in all patients; left ventricular ejection fraction (LVEF) increased normally by 7 to 10% in 4 (2 male, 2 female), but did not increase significantly in 1 (male) and decreased by 3 to 8% in 3 (female). There was no significant difference in the duration of T, resting and exercise HR and SBP, or resting LVEF, between patients with normal and abnormal responses. The change in LVEF was inversely correlated with serum T4 (r= −.82, p<.02) and T3 (r= −.88, p<.05). Three abnormal and 2 normal responders were reassessed after return to euthyroid state. Resting HR and SBP were considerably lower than during T; resting LVEF was 64% ± 6. With exercise, HR and SBP rose to levels attained during the first study; LVEF increased in all patients by 7 to 23%. Our study suggests that T causes diminished LV reserve (compensated functional cardiomyopathy) which appears to be reversible. Severity of T (measured by T4 and T3 levels) may be a determining factor in the development of the functional cardiomyopathy.