Contact Lens Case Reports
A Case of Sclerocornea
BY PATRICK J. CAROLINE, FAAO, & MARK P. ANDRÉ, FAAO
Our patient is a 14-year-old male who has binocular sclerocornea, hyperopia, and accommodative esotropia. Sclerocornea is a unilateral or bilateral congenital anomaly characterized by a nonprogressive, noninflammatory thinning of the peripheral, paracentral, and/or central cornea. The condition may be circumferential (peripheral sclerocornea) or may involve the entire cornea (total sclerocornea). Involved areas show almost total corneal opacification, with fine, superficial, or deep vessels that are extensions of the normal sclera, episclera, and conjunctival vessels.
Sclerocornea affects both males and females equally and may be inherited as a dominant or recessive trait. Visual acuity may be severely affected, with vision in some cases reduced to a level of light perception.
Our Patient’s Case
Our patient presented with uncorrected visual acuities (VAs) of 20/60 in the right eye and 20/50 in the left eye. The cycloplegic refraction was right eye +3.75 –2.75 x 120, 20/50 and left eye +4.00 –2.50 x 040, 20/40.
Slit lamp examination showed midperipheral and peripheral thinning of the right and left corneas, with an arcuate scar in the superior midperiphery of the right cornea. Conjunctival blood vessels were noted 360º around in both corneas; however, the vessels were more prominent in the superior quadrants of both eyes (Figures 1 and 2). There was a loss of transparency in the periphery of both corneas, again greater in the superior corneas and more so in the right eye than in the left. Corneal mapping revealed a corneal elevation differential of 413 microns for the right eye and 416 microns for the left. The corneal powers ranged from 28.25D to 47.75D for the right eye and from 27.87D to 45.62D for the left eye.
Figure 1. Sclerocornea, right eye.
Figure 2. Sclerocornea, left eye.
We first attempted to fit the patient with a number of corneal lens designs, but these lenses all failed to provide an adequate peripheral fitting relationship. We ultimately fitted the patient with a small-diameter scleral lens design called the ICD 14.5 (Paragon Vision Sciences) in parameters of OD 3,100µm sag, 8.8mm base curve, 14.5mm diameter, and +6.00D power, with a standard posterior cornea clearance zone and a –10 (shallower) limbal clearance zone (Figure 3). The lens for the left eye was identical to that for the right eye. Best-corrected VAs with the contact lenses were 20/50 OD and 20/40 OS.
Figure 3. Right eye and left eye corneal topography with small-diameter scleral lenses.
At the one-month follow-up visit, the patient was doing extremely well with these small-diameter scleral lenses and was able to wear them 12 to 16 hours a day with no discomfort. He said that his subjective VA was significantly better with the lenses at 20/40 in both eyes. CLS
Patrick Caroline is an associate professor of optometry at Pacific University. He is also a consultant to Contamac. Mark André is an associate professor of optometry at Pacific University. He is also a consultant for CooperVision.