Ocular Albinism... and Then Some

A 59-year-old Hispanic woman presented with complaints of foreign body sensation, photophobia, irritation in both eyes for 1 month and itching in her eyelids. Her medical history included oculocutaneous albinism, esophageal reflux, and osteoarthritis. She reported a history of radial keratotomy (RK) in both eyes 15 years ago. Her medication list included aspirin and omeprazole. Her BCVA was 20/150 OD and 20/180 OS. Her pupils were reactive to light with no relative afferent pupillary defect. Her visual fields were generally constricted, and she had nystagmus of moderate amplitude in all positions of gaze. The patient’s retinoscopy readings were -0.50 -4.50 x 060 - 20/150 OD and -0.50 -2.00 x 035 - 20/180 OS. Her vision did not improve on subjective refraction and her topography readings were unreliable due to her nystagmus.

Anterior segment evaluation revealed mild meibomian gland dysfunction and Demodex blepharitis (Figure 1). Poliosis was present in her eyebrows and eyelashes. Her lids were mildly tylotic with telangiectasias, indicating ocular rosacea. She had mild, diffuse conjunctival hyperemia with more than nine spots of conjunctival staining with sodium fluorescein. Twelve RK scars were visible in the corneas of each eye with 2+ diffuse superficial punctate keratitis and 2+ corneal neovascularization inferiorly OD (Figure 2). Tear breakup time (TBUT) was 0 seconds in each eye. There were circumferential transillumination defects in both irides, her angles were open to the ciliary body, and she had mild 2+ cortical sclerotic cataracts in each eye.

Posterior segment examination was remarkable for reduced pigmentation of the retinal pigment epithelium (RPE) and increased choroidal reflectivity, macular hypoplasia, peripapillary atrophy, and physiologically large, tilted nerves in each eye. The exam, in general, was difficult for the patient due to extreme discomfort and photophobia.

Meibography documented mild meibomian gland dilation. Tear osmolarity was 334 mOsm OD and 317 mOsm OS. Matrix metalloprotein 9 (MMP-9) testing was positive in both eyes.

The patient’s score on the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire was 21 out of 28. She reported a history of using artificial tears and of insertion of punctal plugs with no relief in symptoms. She also reported that soft contact lenses kept popping off her eye due to her nystagmus.

At this visit, she was diagnosed with severe dry eye disease (DED). She was prescribed use of a heat mask, over-the-counter tea tree oil foaming cleanser (Ocusoft), omega-3 fatty acid supplementation (PRN Physician Recommended Nutraceuticals), and loteprednol etabonate ophthalmic suspension 0.5% (Lotemax, Bausch + Lomb) one drop four times daily in each eye. She was instructed to use preservative-free artificial tears during the day as needed.

THREE WEEKS LATER

At follow-up 3 weeks later, the patient’s tear osmolarity had improved slightly to 325 mOsm OD and mOsm 316 OS. MMP-9 testing was now negative, and her SPEED score was 17 out of 28. The conjunctival hyperemia and symptoms of foreign body sensation had improved slightly. TBUT was still 0 seconds in both eyes.

Microblepharoexfoliation (BlephEx) was performed in the office with success. This patient was not a candidate for in-office thermal pulsation because of her nystagmus. Her cornea still had 2+ staining.

At this visit she was placed on cyclosporine ophthalmic solution 0.09% (Cequa, Sun Ophthalmics) twice daily in both eyes for long-term antiinflammatory treatment. She was asked to continue use of the heat mask, tea tree oil foam, loteprednol four times daily, and omega-3 supplements and to return in 1 month for further follow-up.

ONE MONTH LATER

At this follow-up visit, tear osmolarity was 320 mOsm OD and 322 mOsm OS. MMP-9 testing was positive in each eye. SPEED score was 18 out of 28. The patient’s Demodex load had decreased after the in-office BlephEx treatment, and the itching in her eyelids had improved.

The patient’s eyelids were visibly less hyperemic, but she was still experiencing a foreign body sensation and significant irritation. On anterior segment evaluation, corneal filaments had now developed on the inferior cornea, with significant punctate epithelial erosions and mild microcystic epithelial edema at the base of the filaments in both eyes (Figure 3). Epilating or removing the filaments was not a feasible option because of her extreme photophobia and nystagmus in all gazes.

Instead, a 12-mm dehydrated amniotic membrane transplant (Clarity, Baseline Ophthalmic Systems) was placed in the right eye with an overlying bandage contact lens. Ofloxacin ophthalmic solution 0.3% was prescribed for her to use four times daily. The steroid was continued in the left eye until the following week.

ONE WEEK LATER AND BEYOND

The patient returned 1 week later with near complete resolution of her filaments (Figure 4) and a SPEED score of 10 out of 28. She reported a significant improvement in her symptoms. A dehydrated amniotic membrane was placed in the left eye at this visit, and significant resolution of filaments was seen at follow-up 1 week later.

After this, the patient was scheduled for a 1-month follow up with continuation of heat mask, tea tree oil foam, omega-3 fatty acid supplementation, and cyclosporine twice daily in each eye. A referral was also placed for a scleral contact lens fitting, which it is hoped may facilitate improved vision, decreased photophobia, and a more well lubricated cornea. Additionally, the patient was referred for a rheumatology consult to rule out a systemic etiology, such as Sjögren syndrome.

At the patient’s latest visit, a drastic improvement was seen in her lashes (Figure 5).

DISCUSSION

Histopathologically, corneal filaments are composed of degenerated corneal epithelium at the core, surrounded by degenerated conjunctival epithelium and membrane-associated mucin. Filaments originate from injury to the corneal epithelium, which is then exacerbated by surface inflammation, reduced aqueous production, and mechanical shearing of the eyelids against the epithelium.¹ With each blink, a microtrauma occurs to the corneal epithelium, often causing significant pain for the patient. Filaments vary in size and location on the cornea, always presenting with at least one end adhered to the corneal epithelium. Filamentary keratitis (FK) has been associated with superior limbic keratoconjunctivitis, recurrent corneal erosion, neurotrophic keratitis, bullous keratopathy, and severe ocular surface inflammation.

Treatment typically involves removal of the filaments. An experienced clinician can gently remove the filaments with forceps under topical anesthesia, being careful not to cause more epithelial trauma. Compounded topical 10% N-acetylcysteine has been reported to dissolve filaments, and autologous serum tears may facilitate control of inflammation. Bandage contact lenses, amniotic membranes, and botulinum toxin injection to the pretarsal muscle can all facilitate resolution of FK.²

Concurrent management of ocular surface disease is imperative to control inflammation. FK can take weeks to months to resolve and is typically recurrent and even recalcitrant. Long-term use of topical immunomodulation may be necessary.

Newer treatments for FK involve use of scleral lenses to control inflammation and provide lubrication to the ocular surface. Systemic etiology that may contribute to the topical inflammation and/or aqueous-deficient component of the DED should be investigated.

Oculocutaneous albinism is a group of genetic disorders characterized by a reduction or absence of melanin in the hair, skin, and eyes. One in 70 people carry the gene worldwide. Individuals may present with varying nystagmus, irregular astigmatism, strabismus, reduced visual acuity, and pronounced photophobia.³

This patient’s case was further complicated by a history of RK, a surgical procedure that aims to correct myopia with deep radial corneal incisions. Sequelae of RK include irregular astigmatism, fluctuating vision and diurnal refractive error, glare, DED, and corneal endothelial degeneration.^4,5

Confocal laser microscopy has shown decreased nerve fiber layer density in post-RK corneas due to aberrant corneal nerve regeneration, further contributing to DED and neurotrophic keratitis.⁶ As a possible treatment option, cyclosporine has been shown to facilitate corneal nerve healing up to 3 months after LASIK.⁷

TO THE FUTURE

Given the imbalance on this patient’s delicate ocular surface, she may achieve more visual comfort and less photophobia with the use of a rehabilitating scleral contact lens. A low vision evaluation may be needed if her visual potential is limited with scleral contact lenses. Intense pulsed light therapy may also be considered for chronic management of her Demodex blepharitis and ocular rosacea, as well as alternative forms of meibomian gland expression.