Quantitative computed tomography for bone mineral measurement: technical aspects, dosimetry, normal data and clinical applications.
A single KVp quantitative CT (QCT) technique was used for measuring the spinal trabecular bone density. The trabecular bone equivalent density (TBED) was expressed as the density of a K2HPO4 solution that exhibits a linear attenuation coefficient identical to that of trabecular bone. A field non-uniformity correcting factor was obtained from experiments on phantoms. The effective equivalent dose of the whole examination (four sections and a scout view) is 370 muSv. The in vivo short-term precision (reproducibility coefficient of variation) ranges from 1.4% to 4.1% depending on the TBED values of the normal subjects. The TBED was measured in 206 normal Greeks aged 30-69 years. Average TBED decreased with increasing age for both sexes. Analysis considering separately each vertebra showed a tendency to a caudal spinal TBED reduction. No correlation was found between the TBED values and the body habitus, milk consumption, smoking habits in men, and number of full-term pregnancies. A significant difference (p less than 0.01) was found between the TBED values of the normals and those of 50 women suffering from post-menopausal osteoporosis, 37 alcoholic men, and 12 gastrectomized men (Billroth II). Quantitative CT has been established as a method of measuring TBED in health and disease, and the results from this study confirm these applications.
Karantanas
A H
AH
Department of Medical Physics, Medical School, University of Ioannina, Greece.
Kalef-Ezra
J A
JA
Glaros
D C
DC
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology; D000437:Alcoholism / Q000473:pathology; D015519:Bone Density; D005260:Female; D005743:Gastrectomy; D006801:Humans; D008297:Male; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000473:pathology; D011829:Radiation Dosage; D012737:Sex Factors; D013131:Spine / Q000737:chemistry; D014057:Tomography, X-Ray Computed / Q000379:methods*