[Quantitative study of spinal bone atrophy by computed tomography].

T Shigematsu

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PubMed · 6491423

[Quantitative study of spinal bone atrophy by computed tomography].

T Shigematsu

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Abstract

A method of quantitative measurement of vertebral bone mineral content using the computed tomography (CT) number as an index was deviced. Basic and clinical studies were performed and its clinical applicability was evaluated. The CT number of vertebrae was shown to be highly reproducible; thus, the variations of two measurements between 1 and 336 days observed on the same vertebral body of 13 cases were averaged 3.1. By immersing the isolated autopsy lumbar vertebral bodies in water and then removing the air by aspiration the comparison of CT number showed that in vivo condition could be stimulated. The CT number of the cancellous bone examined in this phantom model with such treatment was found to closely correlate with the Ca content. The CT numbers of the cancellous and cortical bone of lumbar vertebral bodies were investigated from 200 subjects and the CT numbers were decreased gradually with age. Furthermore the tendency of the decline in CT number of cancellous bone at ages over 50 was more distinct in females than males, and in the cortical bone the presence of bone spiculae tended to be associated with a higher CT number. The changes with age were noted in the distribution pattern of CT number in the cancellous bones from the same 200 subjects and the possibility that osteoporosis begins at the periphery of cancellous bone was suggested. This method was used clinically for sequential chronological evaluation of the mineralization status of lumbar vertebrae. The situations sometimes develop that it is impossible to continue the evaluation on the specific vertebral body. In such cases, an adjacent lumbar vertebral body could instead as the target.

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Adolescent Adult Age Factors Aged Atrophy Child Female Humans Male Middle Aged Minerals Osteoporosis Sex Factors Spine Tomography, X-Ray Computed Journal Article

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T Shigematsu. 1984. [Quantitative study of spinal bone atrophy by computed tomography].. https://pubmed.ncbi.nlm.nih.gov/6491423/

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