Representative amyloid-positive and -negative subcutaneous abdominal samples, stained with the CR–derivative FSB. (A) Paired images from amyloid-positive and amyloid-negative samples, acquired under confocal microscopy and phase-contrast analysis. (B-E) Distinct patterns of amyloid deposition (corresponding CR-PL images are visible, respectively, in panels F-I). (B) Pericellular distribution (ALλ patient). (C) Diffuse interstitial distribution (ALλ patient). (D) Focal interstitial (ATTRwt patient). (E) Tiny scattered amyloid foci (ALλ patient). Scale bars, 100 μm in all FSB panels; 200 μm in all CR panels. In the pericellular type, amyloid is distributed around cells and defines the contour of the adipocytes, whereas the interstitium is not enlarged. In contrast, in diffuse and focal interstitial types, large (widespread or localized, respectively) accumulations of amyloid are seen between cells. In the last type (E), tiny amyloid deposits are scattered across the sample in the interstitial space and within vessels.