Spinal bone mineral density in 335 normal and obese children and adolescents: evidence for ethnic and sex differences.

Spinal bone mineral density (BMD) and anthropometric measures were studied in 312 nonobese and 23 obese black, white and Hispanic children and adolescents age 5.00-18.99 years. In adolescents BMD correlated with age, weight, height, fat-free density, body mass index, and midarm circumference. Utilizing the entire group of 312 nonobese subjects, mean Z scores were calculated for comparison versus reference subgroups for bone mineral density index (BMDI, BMD/weight). BMDI was greater for black than for white and Hispanic children and adolescents across all ages studied. Female adolescents accumulated spinal mineral more rapidly than male adolescents. Black males had greater mineral than white and Hispanic males. Differences in BMDI between subgroups could not be explained by differences in body weight or spinal vertebral size. BMDI proved a more sensitive measure for comparing subgroups than did BMD. The study provides normative data and a quantitative methodology for analyzing differences in spinal mineral between groups of children and adolescents.

SPECT versus planar liver scintigraphy: is SPECT worth it?

Five hundred three planar and SPECT hepatic studies were reviewed separately by two experienced observers looking for focal disease. An equivocal reading meant referral to ultrasound or computed tomography (US/CT). The increase in correct readings and decrease in US/CT referrals per 100 positive and per 100 negative SPECT readings were calculated, then the increase in correct readings and decrease in US/CT referrals for various positive rates of liver involvement determined. At our institution, the overall positive rate is approximately 13% yielding 1.1 and 0.83 more correct readings and 1.8 and 2.0 fewer US/CT referrals per 100 cases for each reader, respectively; a marginal benefit for SPECT over planar scintigraphy.

Indium-111 chloride imaging in chronic osteomyelitis.

Sixty-eight patients with clinically suspected chronic osteomyelitis were studied with [111In]chloride. Fifty-four images were categorized as true positive; seven were categorized as true negative. There were four false-positive studies, two of which were associated with healing cancellous bone grafts. There were three false-negative studies in patients previously treated with long-term antibiotic therapy. Images in eight noninfected healing fractures 3 to 8 mo old were normal. Three patients with infected total hip prostheses had positive images. Two patients with loose prostheses had negative images. This study shows that [111In]chloride imaging is an accurate way to localize chronic osteomyelitis and may overcome some of the disadvantages of [67Ga]citrate such as localization in noninfected healing fractures and in some loose [67Ga]citrate such as localization in noninfected healing fractures and in some loose prostheses.

Indium-111 chloride imaging in the detection of infected prostheses.

Thirty-three patients with painful joint prostheses and a suspicion of infection were imaged with [111In]chloride. A final diagnosis was established by culture in 19. Of these, 12 were categorized as true positives and three as true negatives. There were two false-positive studies, occurring in patients with knee prostheses. In both, the culture was obtained by aspiration. Two false negatives were in patients with hip prostheses, one of whom had been on long-term antibiotic suppressive therapy. The sensitivity was 86%, specificity 60%, and accuracy 79%. Seventeen of the proven cases had bone imaging prior to [111In]chloride imaging. All 17 static images were positive and were not helpful in differentiating loosening from infection. Using increased uptake on the blood-pool image as a criteria for infection, the sensitivity was 89%, but the specificity was 0. Adding flow studies made little difference in interpreting the blood-pool images. This study shows that [111In]chloride accurate in evaluating infection in prosthesis than bone imaging.

ECG gating of thallium-201 myocardial images: effect on detection of ischemic heart disease.

Using the angiographic findings as the standard, we have examined the sensitivity and specificity of ECG-gated static thallium-201 myocardial images in 54 patients undergoing selective coronary arteriography. Gated and nongated images, each in anterior, 45 degrees LAO, and 65 degrees LAO projections, were processed by interpolative background subtraction. They were then analyzed separately by four independent observers who were unaware of patient identity, the results of coronary arteriography, and which studies were gated or nongated. No significant differences were observed between the gated and nongated images regarding sensitivity or specificity, the detection rate for reversible myocardial ischemia, the accuracy of prediction of arteriographic extent of disease, or the degree of inter- or intraobserver variability. We conclude that ECG-gated acquisition of T1-201 images does not produce any significant advantages, at least when interpolative background subtraction is used.

Clinical studies with In-111 BLEDTA, a tumor-imaging conjugate of bleomycin with a bifunctional chelating agent.

Indium-111 BLEDTA, a bleomycin analog containing an EDTA group, was used for tumor imaging in 110 patients with cancer. Scans with In-111 BLEDTA agreed with biopsy results in 75 of 95 patients (79% accuracy). A positive scan was obtained in 71 of 88 patients with a positive biopsy (81% sensitivity). In 21 of 95 patients (22%), the scan revealed tumor sites that had not been detected. The main limitation of visualization was the size of the tumor (1.5--2.0 cm diameter was the smallest size seen). Background radioactivity in the liver, spleen, and bone marrow also made tumor detection in these areas more difficult. The cause of this background, and of false-positive uptake in sites of inflammation, is correlated with specific radiolabeling of polymorphonuclear leukocytes by In-111 BLEDTA. Means of eliminating this background are discussed.

Aortoiliac-graft infection. Detection by leukocyte scan.

Infection of a vascular synthetic graft in the aortoliac position is a lethal complication of vascular reconstructive surgery. Difficulties in diagnosis and the subsequent delays in treatment are significant factors in the excessive mortality. Currently available diagnostic methods are extremely limited in their ability to detect infection in the retroperitoneal position, particularly at an early stage. A case is reported in which an aortoiliac-graft infection was detected by a leukocyte scan using indium 111 while the infection was at a relatively subtle clinical stage, and possible future application of leukocyte scanning to this difficult diagnostic problem is discussed.

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.

Magnetic resonance imaging in patients with unstable angina: comparison with acute myocardial infarction and normals.

The role of magnetic resonance imaging in characterizing normal, ischemic and infarcted segments of myocardium was examined in 8 patients with unstable angina, 11 patients with acute myocardial infarction, and 7 patients with stable angina. Eleven normal volunteers were imaged for comparison. Myocardial segments in short axis magnetic resonance images were classified as normal or abnormal on the basis of perfusion changes observed in thallium-201 images in 22 patients and according to the electrocariographic localization of infarction in 4 patients. T2 relaxation time was measured in 57 myocardial segments with abnormal perfusion (24 with reversible and 33 with irreversible perfusion changes) and in 25 normally perfused segments. T2 measurements in normally perfused segments of patients with acute myocardial infarction, unstable angina and stable angina were within normal range derived from T2 measurements in 48 myocardial segments of 11 normal volunteers (42 +/- 10 ms). T2 in abnormal myocardial segments of patients with stable angina also was not significantly different from normal. T2 of abnormal segments in patients with unstable angina (64 +/- 14 in reversibly ischemic and 67 +/- 21 in the irreversibly ischemic segments) was prolonged when compared to normal (p less than 0.0001) and was not significantly different from T2 in abnormal segments of patients with acute myocardial infarction (62 +/- 18 for reversibly and 66 +/- 11 for irreversibly ischemic segments). The data indicate that T2 prolongation is not specific for acute myocardial infarction and may be observed in abnormally perfused segments of patients with unstable angina.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular aneurysm in short axis: a comparison of magnetic resonance, ultrasound and thallium-201 SPECT images.

Short axis magnetic resonance images of a left ventricular aneurysm were compared to similar views obtained by echocardiography and by thallium-201 single photon emission computed tomography. Images of the dyskinetic left ventricular apex and the contractile left ventricular base were analyzed and compared. Unlike the previously reported orthogonal plane magnetic resonance images, short axis imaging provided representative and quantitative information in views comparable to those obtained by standard noninvasive imaging techniques. These data indicate that short axis magnetic resonance imaging is capable of identifying and sizing the aneurysmal and the residual segments of the left ventricle. The findings may be of prognostic value in patients with left ventricular aneurysm.

Aggressive nature of a "cold" lesion depicted by positive flow and blood pool phases of a bone scan.

One of the explanations of a cold lesion on static bone imaging is the presence of an aggressive, destructive lesion. This is the first reported case of such a lesion with an aggressive nature that was confirmed by abnormal flow and pool images.

In-111-leukocyte scanning in inflammatory renal disease.

In-111-leukocyte scanning has recently been introduced as a clinically effective method for detecting inflammatory disease and abscesses. The authors present six cases that demonstrate the usefulness of this new technique in suspected inflammatory renal disease. Two patients had renal abscesses, two had acute pyelonephritis, one had acute focal bacterial nephritis (acute lobar nephronia), and one had a transitional cell carcinoma with associated acute and chronic inflammation.

Bone scintigraphy demonstrating arthropathy of central joints in ankylosing spondylitis.

Bone scintigraphs in a case of ankylosing spondylitis exhibiting a characteristic involvement of sternal and spinal joints are described and discussed.

Indium-111 chloride for detecting suspected hepatomas in patients with focal defects on technetium-99m sulfur colloid liver imaging.

Twenty-three patients with hepatic cirrhosis and focal defects on Tc-99m sulfur colloid (SC) scintigrams were restudied with In-111 chloride to determine if indium localization in the focal defect is indicative of a hepatoma. Seven of eight patients with proven hepatomas had positive studies; however, six of 15 patients without hepatomas also had studies interpreted as positive. Thus, In-111 chloride is highly sensitive for the detection of hepatomas, and a negative indium study would militate against this diagnosis. The high false-positive rate found may be due to technical factors rather than a lack of specificity of localization; the experience of others seems to support this impression. At present, In-111 chloride scintigraphy for focal hepatic defects appears to be useful in ruling out hepatoma.

Indium-111 chloride bone marrow imaging in chronic renal disease.

Eight patients with anemia and chronic renal disease being maintained by chronic hemodialysis were evaluated with In-111 chloride bone marrow imaging and bone marrow core biopsies. There was no correlation between the erythrocyte cellularity of the marrow and the indium bone marrow scan grade in any patient. Bone marrow imaging can not be used as an indicator of the presence of erythroid marrow in these patients.

Indium-111 leukocyte scanning. False-negative study in a renal abscess.

A 33-year-old man had clinical features of a right renal abscess. Results of excretory urography and ultrasonography showed a focal complex mass lesion in the right kidney. An In-111 leukocyte scan failed to detect the right renal abscess, which later was aspirated under CT guidance and explored surgically. The role of In-111 leukocyte imaging in the detection of intra-abdominal abscesses, with limitations of the procedure, is discussed.

Hyperthyroidism and the single lobe.

A practical approach to the hyperthyroid patient with a single lobe visualized on thyroid scintigraphy, and its impact on therapy is discussed. An illustrative case is also presented.

Indium-111 chloride imaging with ununited fractures.

Twenty patients with ununited fractures and a suspicion of infection had In-111 chloride imaging. Surgically obtained cultures were positive for infection in 12 and negative in eight patients. In-111 chloride images were positive in all 12 patients with infection but also were positive in six of the patients with negative cultures. It is not possible to differentiate infected from noninfected ununited fractures by In-111 chloride imaging.