Eyeworld

EW FEATURE 48 AT A GLANCE • Lubrication and oxygen permeable contact lenses can be used as first-line therapy for neurotrophic keratitis, although the mechanical contact of soft lenses is sometimes enough to trigger a breakdown. • To support the surface and protect it from the environment, scleral lenses, PROSE devices, and amniotic membrane transplantation (AMT) can be used. • Biologics including the recombinant human nerve growth factor cenegermin are promising future options for NK. Improving the ocular surface for cataract and refractive surgeons • November 2018 by Chiles Aedam R. Samaniego EyeWorld Asia-Pacific Senior Staff Writer evaporation nor do they have the same protective effect against fric- tion from the lids." Scleral lenses "Scleral lenses and PROSE treat- ment can be used as therapeutic lens in NK," Dr. Jacobs said. She explained that scleral lenses can be used for support of the surface and protection from the environment. "The disadvantage is that they are approved and are generally worn on a daily basis only and must be taken out and disinfected overnight. The advantage is that there is lower risk of infection than with overnight wear of a soft lens. "There are some instances in which the mechanical contact of a soft lens is enough to trigger a breakdown," she added. "Some patients with NK experience less breakdown in daily wear of a scleral lens or PROSE device than extended wear of a bandage soft contact lens." In Dr. Pflugfelder's experience, scleral lenses do work better than soft contacts. "They can be used on an extended basis for 24–48 hours, if no corneal edema develops," he said. Amniotic membrane transplantation (AMT) "I think that most NK corneas reepithelialize in a couple weeks if a good environment is offered," Dr. are lots of deposits, I would swap for a fresh lens. Otherwise, I might go as long as 2–4 weeks, sometimes longer, without changing or disin- fecting the lens." Meanwhile, patients with herpes zoster ophthalmicus and NK may be treated with judicious use of topical steroids when there is concurrent intraocular and/or corneal stromal inflammation, Dr. Pflugfelder said. Dr. Jacobs will also use a steroid. "After all, the surface breakdown may be related to edema from reduced endothelial function and it won't get better unless the intraoc- ular inflammation is controlled," she explained. "Many neurotrophic patients require a topical, low-dose, 'soft' steroid to suppress the intrin- sic corneal inflammation related to ocular surface breakdown. Typically, I use fluorometholone or lotepre- dnol once or twice daily. I often choose ointment form at bedtime, which besides providing the dose of steroid has a depot effect because of longer dwell time and provides barrier lubrication that is far more effective than drops or gels." Dr. Jacobs emphasized the distinction between ointments and drops or gels. "Gels are not equiv- alent to ointment in this regard, as they are water-based and although they may have longer dwell time, they do not serve as a barrier against cause NK, she said. Less commonly NK may be caused by congenital or genetic conditions associated with reduced corneal sensation— among them familial dysautonomia, Goldenhar syndrome, and Moebius syndrome. Regarding the management of NK, Dr. Pflugfelder said that, unfortunately, "high-quality evi- dence doesn't exist for most current therapies, and treatment strategies are based on case series and expert opinion"—only to be expected giv- en the rarity of the condition. First-line management Dr. Jacobs initiates management with lubricants. "I think initial treatment is lubricant ointment QID," she said. "Besides ointment QID it is important to reduce and modify topical regimens to reduce medicamentosa. Then I will go to bandage soft contact lenses [BSCL] or temporary tarsorrhaphy with transition to a scleral lens or PROSE [prosthetic replacement of the ocular surface ecosystem, Boston- Sight, Needham, Massachusetts] or permanent tarsorrhaphy depending on the clinical situation. Serum tears may be helpful for its lubricant and biological effects." Patching, she said, rarely works. For Dr. Pflugfelder, hydrogel contact lenses are "the first line of therapy for NK. The trend is to use higher oxygen permeable silicone hydrogel lenses on an extended basis under frequent observation," he said. "There are many of these lenses on the market." "I recommend using a high Dk (oxygen transmission) lens that is approved for therapeutic indica- tions," Dr. Jacobs said. "There are several on the market, including Air Optix Night & Day [Alcon, Fort Worth, Texas], AcuVue Oasys [John- son & Johnson Vision, Santa Ana, California], and PureVision [Bausch + Lomb, Bridgewater, New Jersey]. I do not recommend using any daily disposable lens. I think it is import- ant to observe the lens in the clinic after an interval of 30–60 minutes to check on retention and to make sure the lens is not too loose or too tight after it has settled. There is no set rule on how often the lens should be checked or exchanged for a new one. I typically would see a patient at 1 week and go from there. If there Addressing this orphan disease helps improve the ocular surface before surgery A lthough neurotrophic ker- atitis (NK) is designated an orphan disease, with an estimated prevalence of less than 5 in every 10,000 individuals, 1 the degenera- tive condition can lead to reduced corneal sensitivity, spontaneous ep- ithelium breakdown, and impaired corneal healing. A history of a number of ocular and systemic conditions raise the likelihood of neurotrophic kera- topathy, most commonly herpes zoster, herpes simplex, neurosurgery with trigeminal damage or ablation, diabetes, chronic dry eye, and scleral buckle surgery for retinal detach- ment, said Stephen Pflugfelder, MD, James and Margaret Elkins Chair and director, Ocular Surface Center, Baylor College of Medicine, Houston. Tumors and surgery for tu- mors such as acoustic neuromas, schwannoma, and meningiomas, medicamentosa with topical NSAID, certain glaucoma drops, and preser- vatives are also "common culprits," according to Deborah Jacobs, MD, cornea and refractive surgery service, Massachusetts Eye & Ear, Boston, and associate professor of ophthal- mology, Harvard Medical School. Renal failure and immune suppression or compromise are some other systemic conditions that can Managing neurotrophic keratitis Patient with neurotrophic keratitis from impaired trigeminal nerve function after surgery for meningioma. Extended wear of a high Dk silicone hydrogel soft lens, pictured here, resulted in healing of epithelial defect and clearing of corneal haze. Source: Deborah Jacobs, MD

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