Positron emission tomographic measurement of blood-to-brain and blood-to-tumour transport ofSUP82/SUPRb. II: Clinical data and validation of technique

摘要

For pt.I see ibid., vol.34, no.12, p.1773-84 (1989). Computer simulations and error analysis of a simple two-compartment, passive-diffusion exchange model for82Rb across the blood-brain-barrier (BBB) have demonstrated the feasibility of obtaining useful estimates of unidirectional rate constant (K1) and tissue-blood water volume (Vb) in vivo using dynamic positron tomography (PET). The coefficients of variation (CV) in parameter estimates for 20 studies on ten patients are shown to have mean values of 10 for tumour K1and Vb, 6 for normal brain Vband 30 for normal brain K1. Ten test-retest studies show a very high correlation (R2>0.88) between the estimated parameter values. Apparent tissue blood volume (Vb) estimates obtained from82Rb studies underestimate the blood volumes obtained by single-breath C15O studies by approximately 15. The data from these clinical studies are in agreement with the predictions of the computer simulations and suggest the suitability of82Rb/PET in the quantification of BBB functional changes.