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I. CASE HISTORY

A 23 year-old Caucasian male presented for a specialty contact fitting at the Moran Center with a complaint of severely reduced vision, distortion and of the left eye. The patient also reported reduced depth perception. Seven months earlier, the patient had sustained a penetrating injury to the left eye. While repairing the brakes on his car, the tension on a spring gave way, striking his left eye resulting in a large corneal-scleral laceration, uveal mal-position, traumatic , traumatic and a macula- on . The patient underwent multiple surgeries including repair of the corneal-scleral laceration, uveal repositioning, retinal detachment repair with scleral buckle and vitrectomy in order to stabilize the eye. The patient’s ocular and systemic health was otherwise unremarkable.

II. PERTINENT FINDINGS On examination, the visual acuity of the right eye with habitual glasses was 20/20 and the left eye was counting fingers at 2 feet.

Habitual Glasses: OD: -2.25 +0.75 x010 OS: -2.00 +1.50 x004

The extra-ocular muscle movements of both were normal. The right was round and reactive to light while the left eye was aniridic. In the right eye, confrontation visual fields were full to finger counting, and in the left eye, confrontation visual fields were constricted in all quadrants.

Manifest Refraction: OD: -2.25 +0.75 x010 20/20 OS: +10.00 +2.00 x082 20/200

Slit lamp examination of the anterior segment of the right eye was unremarkable. Slit lamp examination of the left eye revealed a 16 mm repaired laceration that started inferior-nasally on the and stretched superiorly to the with 7 nylon sutures still present. Endothelial and fibrovascular scarring was present along the laceration as well. Nearly complete traumatic aniridia was noted along with no lens (including no lens capsule).

A non-dilated exam was performed to examine the posterior pole. The right eye was again unremarkable. The left eye showed a few peri-macular pigment abnormalities and an attached macula.

Topography (Zeiss Atlas 2009)  OD: Nearly spherical cornea with normal mires. (44.43D @ 97 / 44.10D @ 7)  OS: Highly irregular cornea/irregular mires with the steepest area just superior to the visual axis and abruptly flattening temporally. (47.77D @ 74 / 39.24D @ 164)

Optical coherence tomography (Heidelberg Spectralis)  OD: Intact photoreceptor integrity line with normal foveal contour  OS: Intact photoreceptor integrity line with a shallow foveal contour

III. DIFFERENTIAL DIAGNOSIS Primary Penetrating globe injury with resulting corneal laceration, traumatic aphakia and aniridia

Other Infectious

IV. DIAGNOSIS AND DISCUSSION A careful review of the patient’s initial encounter in the emergency room revealed the characteristic findings of a penetrating globe injury including:

 Full-thickness scleral and corneal laceration  Severe sub-conjunctival hemorrhage involving 360 degrees of the bulbar  Irregularities in the pupil,  Flattened anterior chamber  Inferior rectus abnormality (The eye wall is thinnest at the insertion points of the rectus muscles, making these areas especially vulnerable to rupture following trauma).

After stabilizing the eye, the new goal of treatment becomes vision rehabilitation. The Ocular Trauma Score (OTS) is an accurate system commonly used to predict the visual outcome of patients after open-globe ocular trauma. Our patient received a OTS score of 2 meaning he has a 27% chance of no light perception, 26% chance of light perception or hand motion, 18% chance of 1/200 to 19/200 visual acuity, 15% chance of 20/200- to 20/50 visual acuity and a 15% chance of >20/40 visual acuity.

Visual rehabilitation obstacles to over-come:  Irregular Cornea due to the corneal laceration and remaining sutures  due to the traumatic aphakia  Photophobia due to the traumatic aniridia

Options for anterior segment and visual rehabilitation include:  Secondary IOL with an iris implant  Contact Lens o Small rigid lenses are known to help resolve visual distortion caused by irregular . However, minor mechanical interactions between the lens and the irregular corneal surface may lead to repeated micro-traumas to the cornea as well as instability of the lens. o Scleral lenses, when fit properly, provides complete corneal clearance making it a good option to mask the irregular surface of the cornea and in this case avoid irritation of the corneal sutures.

V. TREATMENT, MANAGEMENT A specialty contact lens was chosen as the initial treatment due to fewer associated complications and the lower cost in comparison to surgical options. In order to restore vision, reduce distortion and the effects of anisometropia, and vault the delicate corneal surface and 7 remaining corneal nylon sutures, a scleral contact lens was trialed in office:

Trial Contact Lens:  OS: Europa Scleral Lens BC: 46.00 (7.34) DIA: 16.0 OZD: 8.5 PWR: -2.00DS

Examination of the trial lens revealed approximately 350um of central clearance, with the clearance increasing temporally and decreasing nasally. Minimal bearing was noted nasally in the mid-periphery along the laceration . The lens clearly vaulted over the remaining corneal sutures and no blanching of blood vessels was noted.

An over refraction was performed significantly improving the patient’s vision from counting fingers at 2 feet to 20/60+. The patient also reported a decrease in visual distortion and improved depth perception.  Spherical Cylindrical Over-refraction : +7.00 +1.25 x 030

The final contact lens was ordered in a material with a high Dk (100) in order to facilitate oxygen transmission. The optic zone diameter was also increased to reduce the minimal bearing that had been noted in the mid-periphery along the corneal laceration. The power was also adjusted.

Final Contact Lens Parameters:  OS: Europa Scleral Lens BC: 46.00 (7.34) DIA: 16.2 OZD: 8.7 PWR: +6.37 Mat: Optimum Extra

Impact resistant glasses were recommended for full-time wear to protect the “good eye” (OD).

At subsequent follow-up visits, if the patient reports problems with photophobia a custom scleral lens with a iris imprint will be considered in order to reduce the amount of light entering the eye.

VI. CONCLUSION A scleral lens is a good option to significantly improve a patient’s vision following a penetrating globe injury. It is cost effective and has fewer associated complications than additional surgeries. Additionally the new lens designs available, along with lens materials that have high oxygen transmissibility help maintain the health of the cornea long-term.

References Colb K. Management of open globe injuries. International Clinics. 1999:39(1):59-69. Doi:10.1097/00004397-199903910-00008

Fecarotta CM, Friedberg MA, Rapuano CJ, Fisch A, Hawke M. The wills eye manual: Office and emergency room diagnosis and treatment of eye disease (Rhee, the wills eye manual). 6th ed. Gerstenblith AT, Rabinowithz MP, Barahimi BI, eds. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins; February 25, 2012.

Michaud L, van der Worp E, Brazeau D, WArde R, Giasson CJ. Predicting estimates of oxygen transmissibility for scleral lenses. Contact Lens and Anterior Eye. 2012:35(6):266-271. doi:10.1016/j.clae.2012.07.004.

Scott R. The Ocular Trauma Score. Community Eye Health. 2015;28(91):44-45.

Severinsky B, Behrman S, Frucht-Pery J, Solomon A. Scleral contact lenses for visual rehabilitation after penetrating keratoplasty: Long term outcomes. Contact Lens and Anterior Eye. 2014;37(3):196-202. doi:10.106/j.clae.2013.11.001

Van der Worp E, Bornman D, Ferreira DL, Faria-Ribeiro M, Garcia-Porta N, Gonzalez-Meijome JM. Modern scleral contact lenses: A review. Contact Lens and Anterior Eye. 2014:37(4):240-250. doi:10.1016/j.clae.2014.02.002.