Although von Recklinghausen's disease gives rise to neurofibromatous nodules in the iris, and in rare cases causes glaucoma, little has been published concerning gonioscopic characteristics in these conditions. Our examinations of eight patients who had neurofibromata in the irides, but no glaucoma, has shown the anterior chambers of six to have normal angles; the other two had a few strands of iris attaching as far forward as Schwalbe's line, but nothing to suggest tumor in the angle or significant obstruction to aqueous outflow. Findings were quite different in a child who had glaucoma in one eye in addition to the neurofibromatous nodules in the iris. The whole angle in most of the circumference was blanketed by a layer of dense abnormal tissue, presumably neurofibroma tumor tissue, in a position to obstruct aqueous outflow and cause glaucoma.
Grant WM, Walton DS. Distinctive Gonioscopic Findings in Glaucoma Due to Neurofibromatosis. Arch Ophthalmol. 1968;79(2):127-134. doi:10.1001/archopht.1968.03850040129003