A new fiber optic probe for cellular visualization.

Abstract

Thrombus formation within artificial organs has been shown, at least in part, to be caused by retarded or stagnant blood flow. The goal of this work was to develop a magnifying fiber optic probe capable of visualizing particle flow and cellular deposition in a physiologically relevant cellular suspension (blood). The probe has minimal cross sectional area to allow for access to confined areas and to minimize flow disturbance. The probe consists of a germanium oxide fiber optic bundle and a gradient index imaging lens. Fluorescent microspheres of 48 microns, 7 microns, and 3 microns in diameter were imaged after deposition on to a cover slip. The flow (1.44 mm/sec) of 3 microns microspheres suspended in buffer alone and with red cell hematocrits of 10%, 25% and 45% were also visualized. To investigate the potential for this probe to detect ongoing thrombosis, fluorescently labeled human platelets were observed depositing on surfaces from a stagnant platelet rich buffer. These initial data suggest that this probe may offer a technique for the visualization of blood cell adhesion on the interior of artificial organs and the local quantification of flow in such devices.