Ocular Surface & Refractive Review, Vol. 1, Issue 2

& REFRACTIVE

REVIEW A guide to disease management in Asia-Pacific

If the Most Famous Woman in the World Has Dry Eye… Your Refractive Surgery Patients Could Too (And Do).

- page 6

Dry Eye Also Affects Many After Cataract Surgery - page 8

Pterygium Treatment Can Be Simple - page 10

Vol. 1, Issue 2

OCULAR SURFACE & REFRACTIVE REVIEW

Letter to Readers

In this Issue

Treating and Teaching Go Hand-in-Hand T

eachers and physicians have something in common—helping others.

In the medical industry, it is therefore critical to both treat and educate in order to lend a helping hand in making humans healthier.

In fact, pharmaceutical companies like Allergan have a great opportunity to assist in medical education, especially in AsiaPacific, which has been traditionally underserved in this regard.

Dry eye, for example, is a seemingly straightforward term, but it is misleading. Some types of dry eye cause excessive tearing, for example. How can that be dry? Yet, it can be dry eye.

Internally, we are dedicated to engaging our customers with more information.

We believe that salespeople should use product information that is scientifically robust. Medical affairs and training personnel also seek to communicate through content based on medical knowledge. We also look forward to sharing more best-practices so that when questions come up, we have standard knowledge we can refer to.

Each year, we organise a Regional Ophthalmology congress.

We have successfully held six such congresses, inviting physicians from the region and globally to discuss issues that involve the retina, cornea, glaucoma, cataract, neuroophthalmology and ocular imaging.

In each therapeutic area, we hold a Masterclass, which is an opportunity to debate, share handson experience and have a rigorous exchange between audience and speakers. Interestingly, physicians tend to attend Masterclass outside their main specialty.

We also facilitate connections between regional medical institutions and global ones. One of the institutions tends to serve as the anchor—or host—and we will help to facilitate participation so that a global medical village comes together

2

for learning and professional work collaboration.

The Save Sight Years (SSY) programme also was developed as part of Allergan’s commitment to support ophthalmic care for patients. Its objective is to encourage early glaucoma treatment, frequent monitoring and customised treatment.

Last but not least, we offer this issue of Ocular Surface & Refractive Review to advance the dialogue on ophthalmic disease management in Asia-Pacific.

In this issue we focus in on dry eye, especially in relation to cataract and refractive surgery. These issues are deeply intertwined.

Addressing dry eye prior to cataract surgery is especially important because if there is damage to the ocular surface preoperatively, this can lead to a miscalculation of intraocular lens (IOL) power.

Another article focuses on straightforward pterygium treatment.

Bear in mind that pterygium has some inflammatory factors, and to help prevent recurrence, steroids can plan an important role.

We also have an interesting article on NSAIDs and dry eye. Although this may be an important use, note also that NSAIDs are especially useful in the perioperative period in cataract surgery and vitrectomy.

More helpful articles await you in this issue.

We hope you find this educational initiative to be informative, and continue helping more patients in our region and beyond.

Sincerely,

Dr. Kelvin Tan Vice President Medical Affairs Allergan Asia-Pacific

03 Viral Keratitis, Dry Eye and Common Inflammation

05 An Unusual Use for NSAIDs

06

Dry Eye and Refractive Surgery

08

Dealing with Dryness after Cataract Surgery

10

Straightforward Treatment Leads to Low Pterygium Recurrence

12 Impact of Silicone Hydrogel Contact Lenses on the Risk for Corneal Infiltrates

OCULAR SURFACE & REFRACTIVE REVIEW

Viral Keratitis,

Dry Eye and Common Inflammation

By Kyung Chul Yoon, M.D., Ph.D.

V

Ocular Surface & Refractive Review published by

Publisher

Matt Young Editor

Vanessa Caceres Editorial Consultants

Dr. Kamal Asnani Matt Young Project Manager

Ruchi Mahajan Designer

Winson Chua Published in consultation with Allergan Singapore Pte. Ltd. ASIA 0053/2013

Media MICE Pte Ltd 6001 Beach Road, #19-06, Golden Mile Tower, Singapore, 199589 Phone: +65 8186 7677 Fax: +65 6298 6316 E-mail: enquiry@mediamice.com This publication is published by Media MICE Pte Ltd who is solely responsible for its editorial content.

iral keratitis and dry eye treatment often have one major thing in common: inflammation. Treatment for these conditions is unique, but perhaps because of the inflammation overlap, they can be linked.

First, let’s explore viral keratitis and dry eye separately to understand the conditions and their unique treatments.

Then, let’s find common ground— namely, that viral keratitis has some relation to dry eye. And topical cyclosporine—a useful treatment for dry eye—may be helpful as a treatment for viral keratitis as well.

Treatment of Viral Keratitis Viral keratitis is a considerable cause for vision impairment, ranging from benign corneal haze to sightthreatening corneal scarring. Detailed mechanisms of corneal damage are yet to be investigated, but clearly involves replication of DNA or RNA viruses, and inflammatory and immune responses.

Regarding herpes simplex keratitis (HSK) treatment, the Herpetic Eye Disease Study successfully proved that topical corticosteroids were beneficial in reducing persistence or progression of stromal inflammation and shortening the duration of keratitis.1 Generally, potent topical corticosteroids (i.e. prednisolone phosphate) with a high concentration and frequency followed by gradually diminished dosage and infrequent

application for a prolonged period is recommended to prevent recurrence. Soft steroids such as loteprednol with medium potency and lower IOP increasing effect are expected to be safe and effective in the management of HSV keratitis, which requires prolonged application of topical steroids, with less concern about cataract and glaucoma development.2 I think that the use of corticosteroids should be initially combined with antiviral treatment for inflammatory or immune HSV keratitis to decrease the possibility of viral recurrence.

Treatment of Inflammatory Dry Eye It has been known that inflammation in the lacrimal functional unit composed of the ocular surface and lacrimal glands plays a key role in the pathogenesis of dry eye disease.

We have previously reported Th-1 and Th-17 immune responses were up-regulated in the tear film and

All rights reserved.

Three images of viral keratitis

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OCULAR SURFACE & REFRACTIVE REVIEW ocular surface of clinical and experimental dry eye.3 On the basis of the role of inflammation, antiinflammatory treatment including corticosteroids, cyclosporin A, tetracycline, and essential fatty acids have been used.

However, long-term use of topical corticosteroids is at risk for glaucoma or cataract.

Cyclosporine ophthalmic emulsion 0.05%, which blocks production of interleukin-2 and interferonegamma, thereby inhibiting the activation of CD4+ T cells, have been known to be safe and effective in the treatment of inflammatory dry eye, as evidenced by improved clinical parameters, decreased HLA-DR and apoptosis markers, increased goblet cells, and decreased inflammatory T cells and cytokines in the ocular surface and lacrimal gland.

In my experience, topical cyclosporine is effective in most kinds of inflammatory dry eye, which correspond to International Dry Eye Workshop (DEWS) classification Level 2 and 3.4 We found that combined artificial tears and cyclosporine treatment can lead to better improvement in symptom score, Schirmer’s test, tear film break-up time, and tear clearance rate compared to treatment with artificial tears. In our

Five images of dry eye

4

clinical data, cyclosporine 0.05% ophthalmic emulsion was effective in improving symptoms and signs of dry eye associated with graftversus-host diseases and thyroidassociated ophthalmopathy as well as Sjögren’s syndrome.5 I think that compliance with topical cyclosporine is important in treating dry eye because long-term use is needed for improvement, with good compliance leading to rapid improvement.6

Disease Links In 2008, we examined the effect of cyclosporin A on HSK in mice. Topical cyclosporin A was found to effectively reduce stromal haze and inflammation in HSK. A histologic and immunohistochemical analysis demonstrated a significant decrease in the total number of inflammatory cells and T lymphocytes in groups treated with stronger concentrations of cyclosporin A.7 Other research found stromal keratitis to resolve in humans after treatment with cyclosporin A, especially in patients with non-necrotizing keratitis, and in cases not responsive to topical prenisolone.8,9 Topical cyclosporine also reduced recurrence of stromal HSK, even those with prior thermal cautery—which itself has been used effectively as a treatment for stromal HSK.10 Dry eye has been strongly associated with stromal herpetic keratitis itself, with affected eyes showing dryness. Either the dryness could be due to defective reflex lacrimation or could in fact predispose to herpetic infection.

Most patients with HSK may have both reduced tear production and dry eyes.10, 11 Sometimes patients with HSV stromal keratitis may not experience dry symptoms, but can still be found to be dry during testing.12

About the Author Dr. Kyung Chul Yoon, M.D., Ph.D., is Associate Professor and Chief, Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, South Korea.

References 1. Wilhelmus KR, Gee L, Hauck WW, et al. Herpetic Eye Disease Study. A controlled trial of topical corticosteroids for herpes simplex stromal keratitis. Ophthalmology. 1994 Dec;101(12):1883-95.

2. Pavesio CE, Decory HH. Treatment of ocular inflammatory conditions with loteprednol etabonate. Br J Ophthalmol.

2008 Apr;92(4):455-9.

3. Yoon KC, de Paiva CS, Qi H, et al.

Expression of Th-1 chemokines and chemokine receptors on the ocular surface of C57BL/6 mice: effects of desiccating stress. Invest Ophthalmol Vis Sci. 2007 June;48(6):2561-9.

4. The definition and classification of dry eye disease: report of the Definition and Classification Subcommittee of the International Dry Eye WorkShop (2007).

Ocul Surf. 2007 Apr;5(2):75-92.

5. Choi W, Park YG, Cho JK, Yoon KC. Effect of topical 0.05% cyclosporine A in dry eye associated with thyroid ophthalmopathy. J Korean Ophthalmol Soc. 2010 Oct;51 (10):1319-26.

6. Im SK, Yoon KC. Factors affecting compliance with 0.05% cyclosporine emulsion in patients with dry eye syndrome. J Korean Ophthalmol Soc. 2010 Jul;51(7):921-6.

7. Yoon KC, Heo H, Kan IS, et al. Effect of topical cyclosporin A on herpetic stromal keratitis in a mouse model.

Cornea. 2008 May;27(4):454-60.

8. Heiligenhaus A, Steuhl KP. Treatment of HSV-1 stromal keratitis with topical cyclosporine A: a pilot study. Graefes Arch Clin Exp Ophthlamol. 1999 May;237(5):435-8.

9. Rao SN. Treatment of herpes simplex virus stromal keratitis unresponsive to topical prednisolone 1% with topical cyclosporine 0.05%. Am J Ophthalmol.

2006 Apr;141(4):771-2.

10. Sheppard JD, Wertheimer ML, Scoper SV. Modalities to decrease stromal herpes simplex keratitis reactivation rates. Arch Ophthalmol. 2009 Jul;127(7):852-6.

11. Keijser S, van Best JA, Van der Lelij A, et al. Reflex and steady state tears in patients with latent stromal herpetic keratitis. Invest Opthalmol Vis Sci. 2002 Jan;43(1):87-91.

12. Simard-Lebrun A, Boisjoly H, Al-Saadi A. Association between unilateral quiescent stromal herpetic keratitis and bilateral dry eyes. Cornea. 2010 Nov;29(11):1291-5.

OCULAR SURFACE & REFRACTIVE REVIEW

An Unusual Use for NSAIDs

By Joon Young Hyon, M.D.

N

onsteroidal anti-inflammatory drugs (NSAIDS) have widespread usage in ophthalmology from managing postoperative pain after cataract surgery to treating cystoid macular edema.

One lesser-known use of NSAIDs is that involving dry eye management.

Ocular inflammation plays a major role in dry eye disease.

To control inflammation, ophthalmologists typically have used steroids or topical cyclosporine ophthalmic emulsion 0.05%. NSAIDS could be considered as well.

Some patients are steroid responders.

Other patients have a history of glaucoma. In either case, I prescribe a topical NSAID to control ocular surface inflammation in the short term to at least partially replace the steroid and avoid the potential for steroid-related complications.

If an inflamed dry eye patient has a history of glaucoma, for example, both an NSAID and cyclosporine ophthalmic emulsion 0.05% are recommended treatments. If a patient is a steroid

responder, I would avoid a steroid, and use an NSAID or cyclosporine ophthalmic emulsion 0.05% instead. If a patient only has mild inflammation, I would solely use an NSAID. For severe inflammation or SjÜgren’s syndrome, I still prescribe cyclosporine for immediate usage.

Further, if a patient has to maintain long-term treatment of dry eye-related inflammation, topical cyclosporine ophthalmic emulsions, steroids, and NSAIDs all may be helpful.

Although steroids would be the mainstay of short-term treatment and cyclosporine would be beneficial over the long-term, topical NSAIDs could be considered helpful in the medium-term.

Some ophthalmologists have been concerned about some reports of corneal melting with the use of NSAIDs, but the general consensus is those incidents were related to a specific, older NSAID.1,2 Still, I am careful to monitor patients on NSAIDs if there is a problem in the ocular surface.

In South Korea, like in other Asian countries, we observe a significant amount of meibomian gland disease (MGD) along with

dry eye. Topical antibiotics and steroids can be used for the treatment of MGD disease concurrently with treatment for the inflammatory component of dry eye.

Use for Allergic Conjunctivitis Allergic conjunctivitis, which also occurs frequently in Asia, also can be alleviated with NSAID usage.3,4 In both mild and severe cases, I use the NSAID along with an antihistamine ophthalmic drug.

While antihistamines suppress the mast cells, NSAIDs act upon a different pathway to reduce ocular surface inflammation.

About the Author Dr. Joon Young Hyon, M.D., is Associate Professor, Department of Ophthalmology, Seoul National University College of Medicine, Seoul, South Korea.

References: 1. Asai T, Nakagami T, Mochizuki M, Hata N, Tsuchiya T, Hotta Y. Three cases of corneal melting after instillation of a new nonsteroidal anti-inflammatory drug. Cornea. 2006; 25:224-227.

2. Flach, AJ. Corneal melts associated with topically applied nonsteroidal anti-inflammatory drugs. Trans Am Ophthalmol Soc. 2001; 99:205-210.

3. Fujishima H, Fukagawa K, Takano Y, et al. Comparison of efficacy of bromfenac sodium 0.1% ophthalmic solution and fluorometholone 0.02% ophthalmic suspension for the treatment of allergic conjunctivitis. J Ocul Pharmacol Ther.

2009; 25:265-270.

Patients with severe dry eye

Allergic conjunctivitis (vernal keratoconjunctivitis)

4. Schechter BA. Ketorolac tromethamine 0.4% as a treatment for allergic conjuctivitis. Expert Opin Drug Metab Toxicol. 2008; 4:507-511.

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OCULAR SURFACE & REFRACTIVE REVIEW

Cover Story

dry Eye and Refractive Surgery reduces the neural pathway, leading to hypoesthesia and a decreased signal to produce tears.3 Third, a modified corneal curvature can alter the spreading of the tear film over the ocular surface. Often it is a combination of these factors that cause dry eye.

By Robert Edward T. Ang, M.D.

Causes of Dry Eye in Refractive Surgery

T

he ocular surface is an integral part of the visual system.

Any disturbance can affect the vision and comfort of the patient.

Refractive surgery patients are usually demanding. It is advisable that we take note of the ocular surface, tear film, and dry eye of patients because these factors can affect visual outcomes and patient satisfaction.

How does dry eye come about in refractive surgery patients?

First, patients who have worn contact lenses for many years usually complain of dry eye and inflammation, prompting them to seek refractive surgery in the first place.1 Persistent mechanical trauma to the conjunctiva could damage the goblet cells, which later affect mucin production leading to dry eye.2 The inflammation that ensues can affect the lacrimal gland and the tear production pathway, decreasing aqueous production.

Second, cutting the corneal nerves during flap creation

Detecting Dry Eye Before surgery, it is important to diagnose dry eye because it may alter test results such as manifest refraction and topography. Knowing the dry eye status preoperatively can prompt us to manage expectations that affect postoperative comfort and vision. Patient discomfort is one

of the most reliable signs that a patient has dry eye. Patients may complain of grittiness, foreign body or sandy sensation, redness, a persistent feeling of tiredness, and blurred vision. An abnormal Schirmer’s test may be useful but not pathognomonic.

Tear break-up time may be a more useful test for dry eye and can be used to detect recovery or deterioration. Staining may not be very useful because these patients typically have a healthy ocular surface.

In the early postoperative period, the patient may only feel a slight discomfort because corneal sensation has not yet been recovered. More often, patients would notice on and

Mild dry eye with injection and pannus in a contact lens abuser

Moderate dry eye ocular surface conjunctival impression cytology revealing upregulated T-cell markers

Moderately severe dry eye with diffuse neurotrophic central epitheliopathy

Severe dry eye with rose bengal-stained diffuse filamentary keratitis

Editor’s Note: John D. Sheppard, M.D., President, Virginia Eye Consultants, Norfolk, United States, provided images for this article.

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OCULAR SURFACE & REFRACTIVE REVIEW

Cover Story

Diffuse punctate epithelial keratopathy (PEK) seen in moderately severe dry eye, demonstrating predilection for the inferior cornea

off fuzziness or blurred vision that improves after consistent instillation of lubricants. On slitlamp examination, punctate keratitis in the lower half of the corneal flap can be visualized.

Prompt management is needed because patients may start questioning their surgical results if these signs and symptoms are not addressed.

Treating Dry Eye Dry eye management starts before refractive surgery. The right questions and keen clinical observations help to provide the right diagnosis. It is useful to start patients either on artificial tears or cyclosporine a few weeks prior to surgery if the patient is symptomatic and if, upon testing, their Schirmer’s test is less than 5 mm or their tear breakup time is less than 5 seconds.

Some patients present with significant pannus and a hazy epithelial surface due to contact lens intolerance. Prednisolone drops for about 2 weeks can help quiet the ocular surface. A repeat refraction and corneal topography is advisable prior to surgery.

About the Author

As part of preoperative counseling, clinicians should warn patients that there is a period of approximately 6 months that they may have dry eye. This can cause some discomfort, and vision can be affected. They will have to instill eye drops while waiting for the corneal nerves to regenerate and corneal sensation and tearing reflex to recover. This conversation sets the tone in emphasizing their participation in their own eyes’ recovery and motivates their compliance.

I start patients on lubricants like carboxymethylcellulose within the first week after surgery. I urge them to dose at least four times daily. If at 1 week they complain of moderate dryness with or without a significant amount of superficial punctuate keratitis, I generally add a gel at bedtime and will resume cyclosporine ophthalmic emulsion 0.05% if they were instilling this medication prior to surgery. If not, I usually start cyclosporine ophthalmic emulsion 0.05% at 1 month postoperatively if vision is unsatisfactory and persistent dryness bothers patients.

In our practice, we perform corneal presbyopic treatments such as Supracor LASIK and Acufocus Kamra inlays.

Because patients between 45 and 60 years old can be more symptomatic and recovery may be prolonged, I place a punctual plug immediately after surgery.

I dose the artificial tears more aggressively and most, if not all, patients with the Kamra inlay will receive cyclosporine drops for 6 months.

Dr. Robert Edward T. Ang, M.D., is a Specialist in Cornea, Refractive Surgery, Glaucoma and Comprehensive Ophthalmology at the Asian Eye Institute, Makati City, Philippines.

In summary, maintaining a healthy ocular surface is crucial to the success of refractive surgery. The surgery itself may be complication-free, but if the patient has complaints with regard to comfort and vision from dry eye, it can cast doubt on the success of the entire treatment.

Dry eye management should be an important part of patient counseling and postoperative care. (a)

(b)

Confocal microscopy of normal (a) and dry-eye damaged (b) subepithelial nerve plexus using autofluorescence

References 1. Dumbleton K, Woods CA, Jones LW, Fonn D. The impact of contemporary contact lenses on contact lens discontinuation. Eye Contact Lens. 2013 Jan;39(1):93-9.

2. Mantelli F, Massaro-Giordano M, Macchi I, Lambiase A, Bonini S. The cellular mechanisms of dry eye: From pathogenesis to treatment. J Cell Physiol. 2013 May 21.

3. Peyman GA, Sanders DR, Batlle JF, Féliz R, Cabrera G. Cyclosporine 0.05% ophthalmic preparation to aid recovery from loss of corneal sensitivity after LASIK. J Refract Surg. 2008 Apr;24(4):337-43.

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OCULAR SURFACE & REFRACTIVE REVIEW

Dealing with Dryness after Cataract Surgery

Choun-Ki Joo

By Choun-Ki Joo, M.D., Ph.D., and Je-Hyung Hwang, M.D.

D

ry eye-associated symptoms such as foreign body sensation, fatigue, fluctuating vision, and red or watery eyes can occur after cataract surgery.

Symptoms of dry eye emerge in most patients after cataract surgery at 1 week postoperatively and peak at 1 month.1 According to some studies, dry eye occurs more frequently in Asian populations compared to Caucasians, especially after LASIK surgery.

Contributing factors may include racial differences in eyelid and orbital anatomy tear film parameters and blinking dynamics.2 Dry eye disease after cataract surgery likely occurs more frequently in Asian patients compared to Caucasians. Age also plays a role in the development of dry eye disease for all patients. Ductal pathology also can promote lacrimal gland dysfunction.3-5 Palliative treatments focus on increasing lubrication of the ocular surface and improving conservation of existing natural

8

Je-Hyung Hwang

(A)

(B)

(C)

(D)

A-D: Punctate corneal erosions in a dry eye patient after cataract surgery

tears. Lifestyle changes can minimize the effects of the environment or medication that can exacerbate dry eye disease.

Lubrication options include artificial tears, ointments, and gels. Tear conservation strategies include plugging of the puncta and surgery such as tarsorrhaphy.

Limiting Dry Eye Problems After Cataract Surgery Preoperative management of preexisting ocular surface disease is crucial and begins with artificial tears. Anti-inflammatory agents (e.g., topical corticosteroids, cyclosporine ophthalmic emulsion 0.05%) also play a major role in the treatment of preexisting dry eye disease. The management of lid disease such as meibomian gland dysfunction is important as well.6,7 Intraoperatively, frequent irrigation with balanced salt solution or viscoelastics can minimize desiccating stress to the surface. The corneal incision may affect the ocular surface after cataract surgery. Theoretically,

large incisions induce significant damage to the corneal nerves; if possible, one should minimize light exposure with microscopy during the surgery.

Anti-inflammatory agents have a major role in the treatment of dry eye postoperatively.

Topical corticosteroids and immunoregulatory agents constitute the main therapies currently in use. Cyclosporine ophthalmic emulsion 0.05% is widely used because it does not have steroid-induced side effects. In patients with significant aqueous deficiency, consideration should be given to punctual occlusion. Punctal plugs can improve vision in dry eye patients by stabilizing the tear film through decreasing its osmolarity.

Combining punctual plugs with cyclosporine ophthalmic emulsion 0.05% is shown to result in the best Schirmer’s test scores, Rose Bengal staining, and reduction in overall artificial tear use compared to either treatment alone.8-10

OCULAR SURFACE & REFRACTIVE REVIEW Femtosecond LaserAssisted Cataract Surgery Versus Phacoemulsification

Punctate corneal erosions with fluorescein dye staining in a moderately dry eye patient after cataract surgery

The Role of the Cataract Incision A corneal incision may reduce corneal sensitivity and affect the tear production reflex, which is triggered by stimuli to the branch of the trigeminal sensory nerve on the corneal surface. After phacoemulsification, depleted corneal sensitivity occurs not only at the site of incision but also in areas far from the incision site.

Reductions in corneal sensitivity after ocular surface surgery are thought to be dependent on the extent of the corneal incision.

Microincisional procedures such as phacoemulsification are expected to cause less reduction in corneal sensitivity than refractive surgeries and extracapsular cataract extraction.11-14 Corneal sensitivity can take more than 2 years to reach preoperative levels following extracapsular cataract surgery.15

About the Authors Dr. Choun-Ki Joo, M.D., Ph.D., is President, Korea Ocular Infection Society (KOIS), and Professor, Department of Ophthalmology & Visual Science, College of Medicine, The Catholic University of Korea, Seoul, South Korea.

Dr. Je-Hyung Hwang, M.D., is Clinical Fellow, Department of Ophthalmology & Visual Science, College of Medicine, The Catholic University of Korea, Seoul, South Korea.

Phacoemulsification may be associated with corneal damage, such as endothelial cell loss and burns. The rate of endothelial cell loss after phacoemulsification is reported between 1.2% and 12%. New instruments have led to a reduction in the amount of ultrasonic energy delivered to the eye. However,

corneal damage, especially damage to the endothelial cells, remains the main complication of phacoemulsification.16-19 Femtosecond laser-assisted cataract surgery significantly decreases phacoemulsification time and the amount of ultrasound energy compared to standard cataract surgery, perhaps leading to better preservation of ocular structures.

Still, suction ring pressure may cause considerable damage to the limbal goblet cells.20

References 1. Roberts CW, Elie ER. Dry eye symptoms following cataract surgery. Insight.

2007; 32:14–21.

12. Ram J, Gupta A, Brar G, Kaushik S. Outcomes of phacoemulsification in patients with dry eye. J Cataract Refract Surg. 2002; 28:1386–1389.

2. Albietz JM, Lenton LM, McLennan SG. Dry eye after LASIK: Comparison of outcomes for Asian and Caucasian eyes. Clin Exp Optom. 2005 Mar;88(2):89-96.

13. Hoffman RS, Fine IH, Packer M. New phacoemulsification technology. Curr Opin Ophthalmol. 2005; 16:38–43.

3. Moss SE, Klein R, Klein BE. Prevalence of and risk factors for dry eye syndrome. Arch Ophthalmol. 2000; 118:1264–1268.

14. Handwerker HO. Pain and inflammation.

Pain research and clinical management.

In: Bond MR, Charlton JE, Woolf CJ, Eds. Proceedings of the 6th World Congress on Pain. Vol. 4. Amsterdam, The Netherlands: Elsevier, 1991:59–70.

4. Schaumberg DA, Sullivan DA, Buring JE, Dana MR. Prevalence of dry eye syndrome among U.S. women. Am J Ophthalmol. 2003; 136:318–326.

5. Cho P, Yap M. Age, gender, and tear break-up time. Optom Vis Sci. 1993; 70:828–831.

6. Lindstrom RL. The effects of blepharitis on ocular surgery. Ocul Surf. 2009; 7:S19–S20.

7. Chen YA, Hirnschall N, Findl O. Comparison of corneal wetting properties of viscous eye lubricant and balanced salt solution to maintain optical clarity during cataract surgery. J Cataract Refract Surg. 2011; 37:1806–1808.

8. Su MY, Perry HD, Barsam A, et al.

The effect of decreasing the dosage of cyclosporine A 0.05% on dry eye disease after 1 year of twice-daily therapy. Cornea. 2011; 30:1098–1104.

9. Gilbard JP, Rossi SR, Azar DT, Heyda KG. Effect of punctal occlusion by Freeman silicone plug insertion on tear osmolarity in dry eye disorders. CLAO J. 1989; 15:216–218.

10. Roberts CW, Carniglia PE, Brazzo BG. Comparison of topical cyclosporine, punctal occlusion, and a combination for the treatment of dry eye. Cornea.

2007; 26:805–809.

11. Xu KP, Yagi Y, Tsubota K. Decrease in corneal sensitivity and change in tear function in dry eye. Cornea. 1996; 15:235–239.

15. Khanal S, Tomlinson A, Esakowitz L, Bhatt P, Jones D, Nabili S, Mukerji S. Changes in corneal sensitivity and tear physiology after phacoemulsification.

Ophthalmic Physiol Opt. 2008; 28:127134.

16. Mencucci R, Ambrosini S, Ponchietti C, Marini M, Vannelli GB, Menchini U. Ultrasound thermal damage to rabbit corneas after simulated phacoemulsification. J Cataract Refract Surg. 2005; 31:2180–2186.

17. Moschos MM, Chatziralli IP, Sergentanis TN. Viscoat versus visthesia during phacoemulsification cataract surgery: corneal and foveal changes. BMC Ophthalmol. 2011; 11:4–7.

18. Walkow T, Anders N, Klebe S. Endothelial cell loss after phacoemulsification: Relation to preoperative and intraoperative parameters. J Cataract Refract Surg.

2000; 26:727–732.

19. Dick H, Kohnen T, Jacobi F, et al. Longterm endothelial cell loss following phacoemulsification through a temporal clear corneal incision. J Cataract Refract Surg. 1996; 22:63–71.

20. Conrad-Hengerer I, Hengerer FH, Schultz T, Dick HB. Effect of femtosecond laser fragmentation on effective phacoemulsification time in cataract surgery. J Refract Surg. 2012; 28:879-883.

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OCULAR SURFACE & REFRACTIVE REVIEW

Straightforward Treatment Leads to Low Pterygium Recurrence

By Prashant Garg, M.D.

P

terygium may be a “little wing”—based on the Greek word pterygos, which means exactly that—but this wing-like overgrowth of conjunctival and subconjunctival tissue is more than just a little challenging to surgically correct.

Pterygium encroaches upon the cornea, with nasal bulbar pterygium more common than temporal.

Although a large number of pterygium surgery occurs for cosmetic reasons, the surgery also is performed because of irritation, redness, and feelings of discomfort. If pterygium is advanced, decreased vision also is a possibility.

The condition was first described at around 1000 B.C.,1 but there still are controversies regarding how to best manage pterygium. These controversies exist primarily because we do not understand the exact pathogenesis of the disorder. Not only is there a high propensity of recurrence (8% to 12% and even higher), but recurring pterygium are much more difficult to manage than primary pterygium.1,2 Each

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subsequent recurrent pterygium tends to recur more often and also much sooner. Precisely because of these issues, various treatment modalities have been attempted

The Right Treatment Earlier methods of treatment were straightforward enough: excise pterygium and leave bare sclera. However, recurrence was as high as 88%.1 To reduce this high rate of recurrence, several surgical options are employed, including primary closure of conjunctiva, amniotic membranes, and conjunctival autograft, among others. These modifications are primarily aimed at providing coverage of bare sclera left after excision of primary pterygium.

In addition, various additives have been used along with surgery, including mitomycin C (MMC) and 5-fluorouracil (5-FU).1 These additives reduce fibroblastic proliferation and are often combined with other surgical modifications mentioned above.

Images of pterygium

My colleagues and I examined data to determine the best modality of pterygium treatment. We found that the recurrence rate was much lower using conjunctival autograft as compared to other options.4 Several other reports also support our observation and have described conjunctival autograft to be superior to amniotic membrane transplant both for primary and recurrent pterygia.1,3 Beta irradiation also is inferior.

OCULAR SURFACE & REFRACTIVE REVIEW

Astigmatism Considerations

Recurrent pterygium (pictured here) are uglier, harder to operate upon and themselves recur at a higher rate

Meanwhile, the role of additives remains controversial, particularly with regards to the intraoperative use of MMC. MMC has been associated with a higher risk of avascular necrosis of the sclera and conjunctiva, as well as a higher risk of infective scleritis and scleral perforations.4 Similar trends have been seen with the use of MMC postoperatively.

Ocular surface problems also have been strongly associated with 5-FU usage.

Still, there is widespread usage of MMC along with conjunctival autograft. I keep this option reserved only if there is recurrence after a second pterygium surgery.

Surgical Technique There are different ways in which surgeons perform conjunctival autograft. In earlier years, sutures were popular. Currently, we are using fibrin glue.

Ophthalmologists have reported using superotemporal locations—and even the inferior bulbar conjunctiva—as donor sites. There also are variations in size of the excised pterygium, with some surgeons performing limited excision. However, there are reports of very good success rates with extended excision.

I usually prefer extended removal of pterygium followed by conjunctival autograft. My preferred technique was first

described by Dr. Lawrence W. Hirst of Australia.5 He has had a very low rate of pterygium recurrence. In one study of 1,000 consecutive patients undergoing pterygium surgery, only one recurrence occurred. There were some problems—seven patients required further surgery (aside from the one recurrence, there were three graft replacements, one strabismus, one inclusion cyst, and one granuloma). Still, in the study, extended pterygium removal followed by extended conjunctival transplant resulted in one of the lowest recurrence rates reported in scientific literature anywhere.

Think of it as PERFECT (as described by Dr. Hirst): Pterygium Extended Removal Followed by Extended Conjunctival Transplantation.

Conjunctival autograft alone or in combination with adjunctive treatment is the best options for management of primary as well as recurrent pterygia.

Astigmatism associated with pterygium occurs because the fibrovascular growth on the cornea leads to flattening of the cornea in that meridian.

The fact is, various surgical options have no influence on astigmatism postoperatively.

Instead, the degree of postoperative astigmatism is determined by the size of the primary pterygium and the scarring that results after excision.

Unfortunately, you cannot do much to control astigmatism among the various surgical treatment methods.

About the Author

Dr. Prashant Garg, M.D., is Consultant, Cornea and Anterior Segment Services, L V Prasad Eye Institute, Hyderabad, India.

References 1. Kaufman SC, Jacobs DS, Lee WB, Deng SX, Rosenblatt MI, Shtein RM. Options and adjuvants in surgery for pterygium: A report by the American Academy of Ophthalmology. Ophthalmology.

2013;120:201-8.

2. Al Fayez, MF. Limbal-conjunctival vs conjunctival autograft transplant for recurrent pterygia: A prospective randomized controlled trial. JAMA Ophthalmol. 2013; 131:11-16.

3. Shimazaki J, Kosaka K, Shimmura S, Tsubata K. Amniotic membrane transplantation with conjunctival autograft for recurrent pterygium.

Ophthalmology. 2003; 110. 119-124.

4. Fernandes M, Sangwan VS, Bansal AK, et al. Outcome of pterygium surgery: Analysis over 14 years. Eye (Lond).

2005;19:1182-90.

The bare sclera technique has been the basic model for pterygium treatment

5. Hirst LW. Recurrence and complications after 1,000 surgeries using pterygium extended removal followed by extended conjunctival transplant. Ophthalmology.

2012;119:2205-10.

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OCULAR SURFACE & REFRACTIVE REVIEW

Impact of

Silicone Hydrogel Contact Lenses on the Risk for Corneal Infiltrates contact lens surface through lens handling or a contaminated contact lens storage case.

Silicone hydrogel contact lenses show greater bacterial adhesion in vitro than hydrogel contact lenses, although the effect of material type in use is equivocal. Smoking, younger age, and substantial lens bacterial bioburden are associated with sterile corneal infiltrates.

Infiltrates: What the Evidence Shows

By Fiona Stapleton, Ph.D.

Silicone Hydrogel Contact Lenses and Risk Factors Hypoxia-related events were the main reason for the introduction of highly oxygen-permeable (Dk) soft lens materials. Silicone hydrogel lenses provide at least three times more oxygen than conventional hydrogel lenses.

However, microbially-driven, mechanical, allergic, and toxic complications remain with silicone hydrogel lenses. The incidence of corneal infection in extended wear silicone hydrogel use is similar to that of overnight hydrogel lens use, and risk factors are similar for both material types.1-3 There is some evidence to suggest that disease severity in silicone hydrogel contact lens use may be lower.4 With microbe-driven complications such as microbial keratitis and certain corneal infiltrates, a likely cause is microbial adherence to the

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A retrospective records review to evaluate symptomatic soft contact lens-related corneal infiltrate events (CIEs) and their association with soft contact lens material, lens care products, and other risk factors demonstrated that younger patients were at increased risk for CIEs.5 Daily disposable lenses were shown to be protective relative to reusable lenses. Overnight soft contact lens use increased the risk of CIEs in all analyses. Silicone hydrogels increased the risk of CIEs in daily wearers when controlling for the lens care product.

A meta-analysis of 23 studies evaluated the relevant evidence for the risks of corneal inflammatory events in users of high Dk silicone hydrogel lenses and low Dk hydrogel extended wear lenses; there was a strong confounding between material and length of wear.6 In a multivariable analysis, silicone hydrogel lenses had a two-fold higher risk of sterile corneal infiltrates compared with planned replacement hydrogel contact lens use.7 These studies

suggest a two-fold increase in CIE risk with silicone hydrogel soft contact lenses compared to low Dk hydrogel materials.

About the Author Dr. Fiona Stapleton, Ph.D., is Professor and Head of School, School of Optometry and Vision Science, The University of New South Wales, Sydney, Australia.

References 1. Stapleton F, Keay L, Edwards K, Brian G, Dart JKG, Holden BA. The incidence of contact lens related microbial keratitis. Ophthalmology.

2008;115:1655-1662.

2. Stapleton F. The epidemiology of microbial keratitis with silicone hydrogel contact lenses. Presented at the Contact Lens Association of Ophthalmologists, Inc., Eye & Contact Lens meeting, Ft. Lauderdale, Fla. May 2012.

3. Dart JKG, Radford CF, Minassian D, Verma S, Stapleton F. Risk factors for microbial keratitis with contemporary contact lenses. Ophthalmology.

2008;115:1647–1654.

4. Morgan PB, Efron N, Hill EA, Raynor MK, Whiting MA, Tullo AB. Incidence of keratitis of varying severity among contact lens wearers. Br J Ophthalmol.

2005 Apr;89(4):430-436.

5. Chalmers RL, Keay L, McNally J, Kern J. Multicenter case-control study of the role of lens materials and care products on the development of corneal infiltrates. Optom Vis Sci. 2012 Mar;89(3):316-325.

6. Szczotka-Flynn L, Diaz M. Risk of corneal inflammatory events with silicone hydrogel and low dk hydrogel extended contact lens wear: A meta-analysis. Optom Vis Sci. 2007 Apr;84(4):247-256.

7. Radford CF, Dart JKG, Minassian D, Stapleton F, Verma S. Risk factors for non-ulcerative disease in contact lens wearers. Ophthalmology. 2009; 116:385-392.

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