69 PTABLE 26. » Times (Tanve 23 Less THE VALUE IN TABLE 23 FoR 0.2 Year) + Tap ie 24 ; would be, A, yr! rest’ of the, T,yr 0.693 bone ages. r member; ose of the I 2 5 10 20 50 100 lantitativ ugh young. ite that j 1e homeo. 1.17 1.03 0.99 0.98 0.98 0.98 0.98 0.231 0.099 0.046 : 0.020 0.0092 I | 1.06 | 4.03 1.01 1.01 1.00 0.78 0.691: 0.652 , 0.631 0.623 0.638 0.478 0.400 0.358 0.340 0.612 0.414 0.309 0.249 0.223 0.608 0.395 0.268 0.192 0.155 0.608 0.391 0.253 0.160 0.112 0.608 0.391 0.252 0.154 0.099 observed. About 56% of As was augmentation (theo- retically). The 51-year-old man with “Ca examined in 1958 has a blood curve consistent with As5,. = 18.6%/vear. Therefore he ts plotted in Figure 53 at T = 33 years and a diffuse/uniform label of (2%/year)/(18.6 %/ vear) or 0.107. This corresponds to \ = 12 %/year and TABLE 27. Va.LvueEs or PARAMETERS CALCULATED FROM THE Microscopic MopEe. A, yt T, yr 69.3 23.1) 99 46 2.0 0.92 20 100 25.0 29.5! 29.5) 29.5] 32.0 19.0 18.2; 18.0; 31.5: 14.4] 11.8]; 11.7) 30.5 12.0] 8.1] 7.6} 30.0 10.8 5.8] 4.6) 30.0 10.3 4.6 3.0 1 5) 20 100 87.0 81.5 81.5 81.5 49.3 36.3 35.5; 35.3} 38.9 21.8 19.2 19.1) 34.0) 15.5 11.5] 11.1) 31.5 30.7 12.3 11.0 7.3] 5.3 6.1) 3.7 1) 5 20 100 ; 40 36 36 36 65 52 51 51 81 66 61 61 90 7 70 68 e. he human’. the sugmentation rates, but the reduction is only about ct to inf30°, in the region of interest. e volume, tion ratest in) Figure 52 gives augmentation rates (Augs) vs. observed ’ veur). an of the:. (b) Therefore, it does not include apposition but resorption”. docs include secondary mineralization. n rate aff ‘¢) Since new bone is only 75% mineralized, the mal adult. ong-term_: 1; A-Value and Augmentation Rate of loca \ und T excluding bone younger than 10 weeks (0.2 put 15 ES é Augs, %/yr As, %/yr Augs/A 5 eo apposition rate in mass per unit mass per unit time is oe Xy, Ld) ws = Augs + 75% X. The diffuse component will be understood as the nentation , tracer uptake in the original bone laid down at adoles- % original 1 bone left 5 20; 100 ‘his aug- g cence. It is therefore bone of age T years and its local viouslyi augmentation rate 1s Augs = al? ut wou Id at ind1.6 eatio euptakeé | Diffuse Uniform label _ Local Aug; (adolescent bone) As Diffuse/uniform label ' The curves in Figure 53 showdiffuse/uniform label at when , versus T and 4, taken from Table 27. Figure 54 shows fe iF be, wf; versus A and 7 taken from Table 27. n diffuse * '¢) For animals injected at the older ages, quite rate vs.—E low diffuse/uniform ratios are found, but the fraction er thané ntation 2 26.) of the A-value due to augmentation stays over 50%. (Figure 33). The °Ca dog JJ1 (age 10 years) should have a diffuse uniform ratio = 0.25. The value 0.167 was e lowers | 0.61 0.27 0.104) 0.034; 91 96 61 14 — 98 7 | 40 1, 0.77 0.45 0.192) 0.062) 0.88 0.63 0.32 0.108) 90 67 14 0.95 G.79 0.50 0.196} 99 96 83 40 0.98 0.88 0.70 0.323 ~“ oO ; 2.0 aD F coulirmed by the radium cases of Rowland and MarPeshal]” with one exception (case IJ). (See Figure 53.) ‘bi For a given age at injection, the higher the re‘modeling rate the lower the diffuse/uniform ratio. she times Dogs N (age 1 year) and P (age 3 months) fit the mediate § F prediction very well. ye more 0.34 0.119) 0.045) 0.015) o there ab mio:Teling rate should decrease as the age of the person ‘all aug-t ut the time of tracer intake increases. This trend is 79 3.1 31 | -—-~ ; 1.0] — — 98 94 87 81 X= 0.92% /year | Augs /As in Percent nan the, (unelusion ‘+h wider, fo _ oo . sund for! The ratio diffuse/uniform label for a given re- | 5 20 100 50 95 88 79 73 50r 23.| FOF 30 I 2 Let | 69.3 peril 5 10 ! 20 Lo 7 tet 50 100 T (Years after Adolescence - Age of bone at injection) Fic. 55.—The calculated percentage of the total kinetic Avalue (As) that is due to augmentation (Augs) rather than to the deposition of activity in newly-forming bone. Figures from Table 27.