Fig. 4
From: Comparison of ultrasonographic versus infrared pupillary assessment
Scatterplot. Panels a and b demonstrate correlation between UPA and IPA for OD and OS, respectively. Panels c and d demonstrate correlation between UPA and IPA for OD and OS, respectively, in neurocritically ill patients. The blue line would be the perfect match between both techniques. The red line is the fit of a regression on the set of points