24-hour whole-body retention of 99mTc-methylene diphosphonate as indikator of bone tissue metabolic activity in osteopathies

The assessment was introduced of 24-hour whole-body retention of 99mTc-methylene diphosphonate by estimating the amount excreted in urine per 24 hours. The mean value ± standard deviation of 34 subjects without disorders of the skeleton, aged 22 to 70 years, is 34.8±7.1%: 23 men with a value of 35.9±7.4% and 11 women with 32.4±6.3%. The results in pathological conditions (in parentheses the number of examinations): primary hyperparathyroidism (13) 58.4±4.7% (p<0.01); osteoporosis (11) 34.2±3.3% (NS); osteomalacia (16) 59.1±3.8% (p<0.01); acromegaly (10) 37.4±4.1% (NS); not evaluated by statistical methods: Paget's disease (6) 50.4%; multiple metastases in bones (3) 60.7%; malnutritional states (6) 50.5%; myositis ossificans (1) 67.8%. Normal and pathological results are consistent with assumptions and the available experience. The method appears to be a suitable indicator of the metabolic activity of the skeleton for clinical diagnosis and research. (author)