Objective: To report changes in retinal arterial and venous blood flow pattern in two patients with tumors involving the entire optic nerve.
Methods: Retrospective review of one patient with clinical and neuroimaging characteristics typical of bilateral optic nerve gliomas and one patient with a probable meningioma of the left optic nerve sheath.
Results: The optic nerve glioma patient had reduced peak systolic velocity of central retinal arteries bilaterally, while the patient with an optic nerve sheath meningioma had relatively low central retinal artery flow velocity and intermittent blood flow in the central retinal vein on the affected side.
Conclusions: Reduced retinal arterial flow velocities in the setting of optic nerve gliomas may correlate with the presence of optic nerve disease. Phasic blood flow in the central retinal vein with optic nerve sheath meningioma may be the reason that some patients with this tumor develop retinal choroidal venous anastomoses.