The clinical usefulness of the fingers-to-palm ratio in different hand microcirculatory abnormalities

A non-invasive nuclear medicine technique was developed to screen patients with painful hands so as to separate patients with a normal from those with an abnormal microcirculation of the hands in different clinical conditions . Such a technique is important, as the other methods available are either subjective or rather complicated. The study population consisted of 10 heal thy individuals, 23 patients with Raynaud's syndrome and 15 patients with m ixed connective tissue disease (MCTD). Sixty gamma-camera images of the han ds (1 s each) were recorded after a bolus injection of Tc-99(m)-DTPA via a dorsal foot vein. Regions of interest were drawn on the summed images aroun d the fingers and the palmar region. The fingers-to-palm ratio was then cal culated from the total counts inside these regions of interest separately f or each hand. The mean fingers-to-palm ratio was 0.94 +/- 0.18 (0.71-1.25) for the healthy group, 0.57 +/- 0.22 (0.21 +/- 1.11) for the MCTD group and 0.40+/-0.14 (0.18-0.77) for the Raynaud's patients. Analysis of variance s howed these differences to be highly significant (P<0.001). There were also significant differences between 6 MCTD patients in an active (mean 0.48) a nd nine patients in an inactive (mean 0.66) clinical state (two-sample t-te st: P < 0.05). There were no significant differences between the fingers-to -palm ratios of the left and right hands of the same patients tone-sample t -test). Of the 23 primary Raynaud's patients, capillary microscopic data we re pathological in only eight (34%). We conclude that our method is able to differentiate between patients with normal and those with abnormal microci rculation of the hands. Although measurement of the fingers-to-palm ratio i s not a specific method, it is useful both for staging and in the follow-up of patients. ((C) 2000 Lippincott Williams & Wilkins).