Gonioscopic findings in patients with type 1 neurofibromatosis (Von Recklinghausen disease)

Based on the known neurocristopathic etiology of type 1 neurofibromatosis (NF1) and the neuroectodermal embryologic derivation of the iridocorneal angle, we examined a sample of young patients affected with NF1 to see if they have evidence of underdevelopment of the angular region.

We designed a case-controlled clinical study. Forty-two consecutive patients (42 eyes), 24 male and 18 female, affected with NF1 were recruited for the study. Forty-two eyes of 42 consecutive young patients (19 male and 23 female) served as a control group for the iridocorneal angle features studied. Indirect gonioscopy was performed by the means of a Goldmann lens. The intraocular pressure was measured with a Goldmann applanation tonometer. Photographs were taken of the anterior segment and of all the four quadrants of the iridocorneal angle to record the presence of abnormalities. The iridocorneal angle was graded according to the classification proposed by Spaeth. Evaluation of the angle also included the gonioscopic width of ciliary body band (CBB).

In this study we found that 29 of 42 eyes (69%) of the NF1 group had mild anteriorization, even if within normal limits, of the iris insertion and abundant basal iris processes. The CBB was either invisible (54.84%) or very narrow (21.4%). Three NF1 patients had bilateral juvenile congenital glaucoma.

It seems that patients affected with NF1 often have characteristic gonioscopic findings consistent with underdevelopment of the iridocorneal angle.