Vertebral Bone Mineral Density Measured with Dual Photon Absorptiometry Using a Gamma Camera: Clinical Application to Metabolic Bone Diseases

Dual photon absorptiometry (DPA) with a gamma camera, instead of a rectilinear scanner, has been developed for vertebral bone mineral density (BMD) measurement. The system consists of 50 mCi (1,850 MBq) 153-Gd as the emitting source, and an Anger-type gamma camera with a rectangular Nal (Tl) crystal and 22 photomultiplier tubes. The effective field of a view was enough to cover more than 3 vertebrae. With the patient sitting, data acquisition was performed. The spatial resolution and uniformity of the gamma camera were good. With the introduction of a correction equation, the error in calculated BMD due to body thickness was reduced. A data acquisition of 7.5 to 15 min led to a satisfactory C.V. value (less than 2.0%). The precision (1.63% of C.V. in vitro and 3.53% in vivo) and accuracy (r=0.999) of the BMD measurements were also good. Vertebral BMD values in 300 normal Japanese females decreased with aging. Although in involutional osteoporosis and secondary hyperparathyroidism both vertebral and radial % BMDs decreased, in steroid-induced osteoporosis and primary hyperparathyroidism, disproportionate bone loss (relatively lower in vertebral bone) was demonstrated. Thus, it was shown that a newly developed DPA system using a gamma camera provided sufficient precision and accuracy to quantificaticn of vertebral BMD, and its application should provide reliable information for clarification of the pathophysiology of metabolic bone diseases

Increased Uptake of 67Ga-citrate in Cerebral Infarction

67Ga-citrate has been widely used in the detection of malignancy and inflammation. We presented a case of cerebral infarction with increased uptake of 67Ga-citrate.1-3) Although it is reported that 67Ga-citrate was accumulated in cerebral infarction, this finding is must be kept in mind in differential diagnosis between cerebral infarction and cerebral neoplasms or infectious diseases

Measurement of Ionized Calcium as Supplementary Marker of Bone Metastasis in Breast Cancer

The serum concentrations of ionized calcium (iCa), corrected automatically for serum pH, were measured in 67 cases with breast cancer (16 positive cases and 51 negative cases for bone metastasis). The serum concentration of iCa in the cases of positive bone metastasis was significantly higher than that in the negative cases (p<0.005). As osteoclastic bone metastasis occurred frequently in breast cancer, the measurements of serum concentrations of iCa might be of help as a supplementary marker of the diagnosis of bone metastasis

Assessment of Bone Scintigraphy Showing Markedly Increased Accumulation in Mandibular and Maxillary Lesions of Cementifying Fibroma

This report concerns with three cases of cementifying fibroma showing markedly increased accumulation of 99mTc-MDP in mandibular and maxillary lesions. The bone scintigraphic and histopathological findings are presented and discussed

A Newly Developed Instrument of Dual Photon Absorptiometry for Bone Mineral Analysis of the Lumbar Vertebra: Study in Control and Aged Females

In order to determine the quantitatively bone mass, dual photon absorptiometry instrument using a scintillation camera was newly developed, and its basic performance was described. Furthermore, with this instrument, bone mineral at 3rd lumbar vertebra was measured in 57 women (31 controls: age 29.9±6.4 yrs., and 16 seniles: age 67.7±6.6 yrs.). The aged females, compared with the young control females, showed significantly low the all parameters of bone mineral such as bone mineral content (BMC), bone mineral density and total BMC at 3rd lumbar vertebra. Thus, it was shown that assessment of bone mineral with this instrument provided a useful information in the diagnosis of osteoporosis

Scintigraphic Findings of Bone and Bone-Marrow and Determination of Bone Mineral Density Using Photon Absorptiometry in Osteopetrosis

On a 15-year-old girl with osteopetrosis, bone and bonemarrow scintigraphy were performed. Also, bone mineral density (BMD) with quantitative CT (QCT), single photon absorptiometry (SPA) and dual photon absorptiometry (DPA) were measured. On bone scintigraphy the diffusely increased skeletal uptake and relatively diminished renal uptake were noted. On the other hand, on bone marrow scintigraphy poor accumulation in central marrow and peripheral expansion were shown. BMD value by QCT and DPA (mainly trabecular bone) was markedly high, while BMD by SPA (mainly cortical bone) was within normal range. Thus, it was shown that bone and bone-marrow scintigraphy combined with BMD measurement by photon absorptiometry were useful and essential in evaluating the pathophysiology of osteosclerosis