• Blood may be refluxed into Schlemm's canal in the normal eye by occlusion of recipient veins in a sector of the conjunctiva and episclera. The blood makes the anterior margin of the canal distinct near the midportion of the trabecular mesh at the same place in which it is seen after hypotony. Circumferential flow in segments of the canal is possible when a pressure head exists to promote such flow. Evidence was found that the canal is not partially collapsed in the normal eye.
Moses RA, Hoover GS, Oostwouder PH. Blood Reflux in Schlemm's CanalI. Normal Findings. Arch Ophthalmol. 1979;97(7):1307-1310. doi:10.1001/archopht.1979.01020020049011