Modifiable determinants of bone status in young women.

The purpose of this study was to evaluate the contributions of exercise, fitness, body composition, and calcium intake during adolescence to peak bone mineral density and bone structural measurements in young women. University Hospital and 75 healthy, white females in the longitudinal Penn State Young Women's Health Study were included. Body composition, total body, and hip bone mineral density (BMD) were measured by dual-energy X-ray absorptiometry (DXA), exercise scores by sports-exercise questionnaire during ages 12-18 years, and estimated aerobic capacity by bike ergometry. Section modulus values (a measurement of bending strength) cross-sectional area (CSA), subperiosteal width, and cortical thickness were calculated from DXA scan data for the femoral neck and femoral shaft. Calcium intakes were calculated from 39 days of prospective food records collected at 13 timepoints between ages 12 and 20 years; supplemental calcium intakes were included. Section moduli at the femoral neck and shaft were correlated significantly with lean body mass, sports-exercise scores (R(2) = 0.07-0.19, p < 0.05), and aerobic capacity (R(2) = 0.06-0.57, p < 0.05). Sports-exercise scores correlated with BMD at the femoral neck and shaft. Average total daily calcium intake at age 12-20 years ranged from 486 to 1958 mg/day and was not significantly associated with total or regional peak BMD or bone structure measures at 20 years of age. It was shown that achievable levels of exercise and fitness have a favorable effect on BMD and section modulus of the femoral neck and femoral shaft in young adult women, whereas daily calcium intake of >500 mg in female adolescents appears to have little, if any effect.

Bone mineral density and body composition in lean women with polycystic ovary syndrome.

OBJECTIVE: To examine bone mineral density (BMD) and fat distribution in lean women with polycystic ovary syndrome (PCOS) compared with matched control women. DESIGN: Controlled clinical study. SETTING: An academic clinical research center. PATIENT(S): Twelve non-Hispanic white women with PCOS and a body mass index of <26 and 10 healthy control women matched for age, ethnicity, and weight. INTERVENTION(S): Biometric measures, blood sample collection, and total body/regional bone density and fat analysis were performed. MAIN OUTCOME MEASURE(S): Serum levels of androgens, glucose, and insulin were measured. Bone density and fat distribution were measured by total body dual-energy x-ray absorptiometry. RESULT(S): Androgen levels were elevated significantly in the lean women with PCOS compared with the controls. There was no statistically significant difference in total body BMD between the two groups. A significant increase in BMD was noted in the left arm, right arm, and left ribs of the lean PCOS group. Evaluation of upper body BMD showed a significant correlation between testosterone levels and BMD. No statistically significant differences were noted in body fat distribution, although the lean PCOS group tended to have lower mean percentages of body fat. CONCLUSION(S): Lean women with PCOS have regional differences in BMD, with significantly increased BMD in the upper skeleton compared with control women.

Diagnosis and radioablation treatment of toxic multinodular goiter in a hemodialysis patient.

Toxic multinodular goiter is rare in hemodialysis patients. In addition, establishing the diagnosis of hyperthyroidism in the elderly patient with renal failure is difficult because abnormal thyroid function tests can erroneously be attributed to euthyroid sick syndrome. Treatment of hyperthyroidism in dialysis patients by radioiodine ablation involves careful calculation of 131I dose, determination of interval between 131I administration and its removal by hemodialysis, and minimization of radiation hazards during dialytic removal of 131I. We described the clinical presentation of an elderly dialysis patient with toxic multinodular goiter and discussed our diagnostic and therapeutic approaches. The patient's recovery after 131I ablation was complete and uneventful.

Technetium-99m-MAG3 scintigraphy in acute renal failure after transplantation: a marker of viability and prognosis.

UNLABELLED: This study assessed 99mTc-mercaptoacetyltriglycine (MAG3) for determination of renal transplant prognosis for recovery in patients with early postoperative dysfunction. The postulate tested was that good tracer extraction may imply high likelihood of recovery, while poor extraction may confer a poor prognosis. METHODS: A 2-min image acquired 1 min after MAG3 administration, named a cortical uptake phase (CUP) image, was visually analyzed according to standardized semiquantitative guidelines. Interpretation was expressed in tubular injury severity scores (TISS) that ranged from 1 (a normally functioning renal transplant) to 6 (a photopenic defect in place of renal transplant). RESULTS: The study analyzed 64 patients (35 men, 29 women, age 45.9 +/- 14 yr). All five patients with TISS of 6 or 5 lost the transplant. Only 1 of 10 patients with TISS of 4 lost the transplant. All patients with TISS of less than 4 recovered renal transplant function. CONCLUSION: This study suggests that MAG3 scan (the CUP image specifically) is an accurate prognosticator in patients with early postoperative renal transplant dysfunction. Reproduction of these results in a larger population and other institutions is necessary before clinical implementation of this methodology.

Clinical utility of technetium-99m methoxisobutylisonitrile imaging in differentiated thyroid carcinoma: comparison with thallium-201 and iodine-131 Na scintigraphy, and serum thyroglobulin quantitation.

Recently, technetium-99m methoxyisobutylisonitrile (99mTc-MIBI) has been used to image thyroid carcinoma. A prospective study was performed to compare the efficacy of 99mTc-MIBI to thallium-201 (201Tl) scintigraphy in patients with differentiated thyroid carcinoma. The clinical utility of all radionuclide imaging modalities, i.e., 99mTc-MIBI, 201Tl, and iodine-131 Na (131I-Na), as well as serum thyroglobulin estimation, was evaluated. Thirty-four post-thyroidectomy patients (age range: 26-76 years) underwent 45 studies. Histopathologies studied included fourteen papillary, eight papillary-follicular, ten follicular, one Hürthle cell, and one medullary carcinoma of the thyroid. Following optimal stimulation of endogenous thyroid stimulating hormone (i.e, TSH 50 mU/ml), the patients underwent 201Tl and 99mTc-MIBI scintigraphy. Concomitant 131I-Na scintigraphy was performed and serum thyroglobulin levels were measured. Sixteen scan sets were performed prior to 131I-Na ablation therapy. Twenty-nine scan sets were performed following 131I-Na ablation therapy. The presence or absence of thyroid cancer was established by clinical, biochemical, radiologic, and/or biopsy findings. There was no significant difference in sensitivity and specificity of 201Tl scintigraphy versus 99mTc-MIBI scintigraphy in pre- and postablation studies. 131I-Na scintigraphy with determination of thyroglobulin level was sufficient in preablation studies. Among postablation patients, the addition of 99mTc-MIBI or 201Tl offered a higher diagnostic yield. Between the 201Tl and 99mTc-MIBI studies, there was a concordance of 69% in preablation and 97% among postablation patients (P=0.027). It is concluded that 99mTc-MIBI is a suitable alternative to 201Tl scintigraphy in thyroid carcinoma, especially following thyroidectomy and 131I-Na therapy. 131I-Na scintigraphy with serum thyroglobulin is adequate in both pre- and postablation patients. Among the post-131I-Na ablation patients, 99mTc-MIBI or 201Tl is extremely valuable for tumor localization, especially when the 131I-Na whole-body scan is negative. The combination of 99mTc-MIBI or 201Tl scintigraphy with 131I-Na and serum thyroglobulin offers the highest diagnostic yield.

Tc-99m MAG3 renography in renal vein thrombosis secondary to Finnish-type congenital nephrotic syndrome.

Scintigraphic findings in renal vein thrombosis (RVT) have been well described on studies performed with Tc-99m DPTA, Tc-99m glucoheptonate, and I-131 orthoiodohippurate. The authors could find no reports of RVT findings on Tc-99m mercaptoacetyltriglycine (MAG3) imaging. Tc-99m MAG3 renal scintigraphy in an infant with RVT because of Finnish-type congenital nephrotic syndrome is described. Correlative ultrasound and inferior vena cava venogram findings are presented.

Intraperitoneal distribution imaging prior to chromic phosphate (P-32) therapy in ovarian cancer patients.

This study addressed the technique of intraperitoneal distribution imaging (IDI). A literature search (MEDLINE database) revealed wide variations in IDI techniques without a basis for comparison. From April 1990 to September 1992, the authors studied 8 patients (age 43-65 years) with ovarian cancer. A total of 1000 ml of normal saline and 1 mCi of Tc-99m SC was infused intraperitoneally for IDI. In one patient loculation was observed, but only 250 ml of normal saline was infused with Tc-99m SC. A repeat study using our standard technique rendered free intraperitoneal distribution in this patient, as well as in the other seven cases. Some investigators recommend low volumes, but in our experience this produced the finding of pseudoloculation, which could change treatment inappropriately. Although the number of patients studied at our institution was small, administration of 1 liter intraperitoneally provided consistent IDI results.

Scintigraphic evaluation of pediatric urinary tract infection.

Scintigraphic evaluation of urinary tract infection, pyelonephritis, and renal scarring represents a significant portion of a clinical pediatric nuclear medicine practice. Renal scarring from recurring infection remains an important cause of end-stage renal disease and hypertension in the pediatric population. However, the clinical presentation in infants and young children is often elusive, and clinical diagnosis of upper tract involvement is frequently unreliable. As a result, diagnostic imaging has a critical role to play in the localization of infection to the lower or upper urinary tract. Radionuclide cystography and renal cortical imaging have become mainstays of this evaluation. Direct radionuclide cystography is the preferred cystographic screening technique, because it has lower radiation exposure and greater sensitivity for the detection of vesicoureteral reflux than either indirect radionuclide cystography or fluoroscopic contrast cystography. Renal cortical scintigraphy has become the standard for the detection of pyelonephritis and renal scarring. Correlation with histopathology has demonstrated a high degree of diagnostic accuracy. Acute pyelonephritis has been shown to be the necessary etiologic factor for the development of subsequent renal scarring, and the mechanism of renal injury in pyelonephritis has been extensively studied in experimental models. The ability of prompt and appropriate antibiotic therapy to dramatically reduce the incidence of subsequent scarring also has been conclusively demonstrated both clinically and in the experimental model. Vesicoureteral reflux was once thought to be a necessary prerequisite for the development of renal scarring. Although it is clear that the intrarenal reflux of infected urine will create pyelonephritis in the experimental model, the high incidence of pyelonephritis and subsequent scarring in the absence of demonstrable vesicoureteral reflux leaves the role of reflux in question. Although the role of vesicoureteral reflux is incompletely understood, its detection nevertheless remains a standard part of the patient's evaluation.

Scintigraphy of torsion in triorchidism.

A 24-yr-old male who experienced fleeting episodes of left scrotal pain since the age of 13 had an ultrasound that suggested testicular duplication on the side (triorchidism). Five months later he had acute left scrotal pain lasting for 12 hr. At that time routine scrotal scintigraphy revealed late torsion and an additional sitting view demonstrated triorchidism. Literature review indicates that in this rare condition there is an increased risk of torsion. In only two prior reports did an ultrasound examination suggest triorchidism preoperatively.

Clinical application of magnetic resonance imaging of the heart and great vessels.

This report reviews the clinical applications of magnetic resonance imaging, (MRI) for the heart and great vessels based on the first 120 patients studied with 1.5 Tesla scanner. Cine scans were obtained in 85% of patients studied with the remainder having T1 spin-echo imaging. MRI provides high-resolution multiplanar images for defining abnormalities in cardiac structure and is especially useful for congenital heart disease. Cine MR evaluates cardiac dynamic functions such as left ventricular volumes and ejection fraction, left ventricular segmental wall motion, and valvular function. It is also useful for detection of aortic and pulmonary arterial disease and diseases of the pericardium. It is concluded that MR has broad applications for diagnosis of cardiac and great-vessel disorders.

Quantitation of differential renal function with Tc-99m MDP.

This study was designed to evaluate the usefulness of the bone tracer Tc-99m MDP for quantitative assessment of relative renal function as compared with renal imaging radiotracers used for that purpose. Differential renal function, i.e., the percent contribution each kidney makes to global renal function, was determined prospectively in 15 consecutive patients using Tc-99m MDP and a renal radionuclide tracer, either Tc-99m DTPA or Tc-99m GHA. Differential function was computed in all cases from the early (1-3 minutes) renal uptake of the tracers by region-of-interest analysis of the computer-acquired data. There was a high correlation between values of differential function obtained with Tc-99m MDP and those obtained with Tc-99m DTPA or Tc-99m GHA (r = 0.98, P less than 0.0001). Qualitative assessment of the images revealed equivalent scintigraphic patterns in all patients. It is concluded that the early characteristics of renal handling of Tc-MDP are sufficiently similar to those of Tc-DTPA and Tc-GHA so that accurate estimates of differential renal function are possible with this agent, and that Tc-MDP-determined renal differential most likely reflects differential glomerular filtration rate.