Effect of hyperthyroidism and its treatment on bone mineral content.

Patients with hyperthyroidism may develop osteopenia associated with fractures; however, there has been no general agreement on the incidence of osteopenia in hyperthyroidism or the recovery of the mineral loss after treatment of hyperthyroidism. We conducted a longitudinal prospective study on the effect of hyperthyroidism and its treatment on bone mineral content (BMC) using photon absorptiometry. We observed that both young and older hyperthyroid patients showed a significantly decreased baseline BMC compared with age- and sex-matched controls. We also observed a slight recovery of BMC in hyperthyroid patients at the two-year interval after a euthyroid state had been achieved. However, the BMC was still much lower than that of controls, and we did not find any significant restoration of BMC following "cure" of hyperthyroidism.

Effect of calcitonin treatment on the natural course of bone demineralization in Paget's disease.

Numerous studies have been done to determine the effects of long term calcitonin (CT) treatment on Paget's disease of bone, but very few studies have been undertaken to determine the long term CT effect on nonpagetic bone in man. Because of conflicting results of the CT effect on osteoporosis and also for further understanding of the role of CT on normal bone, we conducted a longitudinal prospective study on the effect of CT treatment on nonpagetic bone in patients with Paget's disease using monoenergetic photon absorptionmetry method. Patients with Paget's disease were given salmon CT daily for a period of 3 yr, the bone mineral content (BMC) in the nonpagetic distal radius was measured periodically for 3 yr, and the data were compared with those of the control group of patients with Paget's disease not receiving CT treatment. It was found that the control group showed a persistent gradual decrease in BMC during the study period of 3 yr, but the CT-treated group showed no decrease in BMC during the 3-yr period of treatment. Our study suggests that CT treatment may delay the natural course of bone demineralization with aging in patients with Paget's disease.

Effects of a reduction in crystal thickness on Anger-camera performance.

The performances of two commerical gamma cameras, with crystals 1.3 and 0.6 cm thick, are compared. Phantom studies simulating clinical conditions showed no significant difference in performance at 140 keV. At 68 keV, the thinner crystal gave marginal improvements in camera performance with phantoms simulating clinical conditions. Frequent use with very low-energy emitters, such as Tl-201, would be needed to justify the expense required to refit the 1.3 cm camera with a 0.6 cm crystal.

Acute effects of phlebotomy on right ventricular size and performance in polycythemic patients with chronic obstructive pulmonary disease.

To assess the acute effects of phlebotomy on right ventricular size and performance, gated equilibrium radionuclide angiography was used to evaluate 10 patients with severe chronic obstructive pulmonary disease and erythrocytosis (hematocrit greater than 55%). The mean right ventricular ejection fraction was abnormal before (0.38) but not after (0.43) phlebotomy, and the increase was highly significant (p less than 0.001). Similarly, the right ventricular end-diastolic area decreased significantly from 588 to 505 pixels (p less than 0.02). No significant changes occurred on the left side. Cardiac output was unchanged or slightly increased. Thus, assuming that afterload was unchanged, as reported by other investigators, the data herein are consistent with the hypothesis that a normalization in preload shifts the Starling curve, resulting in improved right ventricular performance with preservation of the cardiac output.

Scintigraphic evidence of transient unilateral sacroiliitis in a case of Whipple's disease.

Investigation of low back pain by quantitative sacroiliac joint scintigraphy (QSS) can detect the presence of sacroiliitis not apparent by roentgenography. Transient unilateral sacroiliitis was documented by QSS in a patient with Whipple's disease during tetracycline treatment, when the peripheral arthropathy was in remission. Thus, the pattern of inflammatory spinal disease, if associated with the intestinal disease, differs from that of the peripheral arthritis.

Ga-67 studies in a patient with acquired immunodeficiency syndrome and disseminated mycobacterial infection.

A well-documented case of acquired immunodeficiency syndrome (AIDS) with diffuse lymphadenopathy and disseminated mycobacteriosis in whom serial Ga-67 studies were performed is presented.

Mobile gamma cameras: a comparative evaluation.

Mobile gamma cameras from three manufacturers were evaluated. Count rate capability, flood uniformity, intrinsic and extrinsic spatial resolution, and sensitivity were compared, using images made under reproducible conditions with phantoms which simulate actual clinical situations.

Quantitative sacroiliac joint scintigraphy. A critical assessment.

With quantitative sacroiliac joint scintigraphy (QSS), sacroiliac joint-to-sacrum (SIS) ratios greater than or equal to 1.40 are abnormal for our method. High SIS ratios are associated with roentgenographically appreciated sacroiliitis and with early clinically evident sacroiliitis. Although highly sensitive, QSS abnormalities are not specific for inflammatory sacroiliac (SI) joint disease. High SIS ratios are also seen in rheumatoid arthritis, degenerative abnormalities of the lumbosacral spine, and metabolic bone disorder. Other disorders with roentgenographic SI joint abnormalities must be studied scintigraphically before QSS can be employed as a useful diagnostic test.

Thallium-201 myocardial imaging in patients on chronic hemodialysis.

10 long-term hemodialysis patients had immediate and redistribution thallium-201 myocardial imaging performed after a course of hemodialysis. Subjects had EKGs done on the same day before and after dialysis. 3 of the 10 subjects had resting thallium-201 myocardial imaging obtained on non-dialysis days. 60% of the electrocardiograms showed changes with dialysis. All 13 thallium studies were abnormal, showing multiple transient filling defects at rest. Most subjects had permanent filling defects as well. It is concluded that hemodialysis patients have a high frequency of abnormal thallium-201 myocardial images at rest. The cause of these abnormal studies is uncertain.