EyeWorld Asia-Pacific June 2012 Issue

June 2012 15 EWAP FEATURE 2-3 months after LASIK and they have pain, almost all of them have lingering inflammation,” Dr. Hamrah said. When treated, the neuralgia goes away. However, “if the patient has had this for 6 months to a year, that becomes difficult to treat,” he said. Dr. Rosenthal agreed that central sensitization could be avoided if the pain is treated early. “I theorize that if we limit the pain and enhance the healing of the nerves and the corneal epithelium, theoretically this devastating centralized pain may be aborted,” Dr. Rosenthal said. “I think there’s a chance of developing that type of intervention.” For advanced disease, Dr. Cason recommended treating the dry eye conditions with lubrication, anticonvulsants, tricyclic antidepressants and serotonin reuptake inhibitors, and the scleral reservoir lens and evaporation- prevention goggles. The problem with the scleral lens is some patients have sensitivity in the conjunctiva and may feel the lens under their eyelid. “Despite the fact that the cornea is completely bathed in fluid, they still have pain sensation,” he explained. “Unfortunately, a lot of these patients aren’t helped by this.” Dr. Hamrah has had some success with autologous serum tears (AST), which promote nerve regeneration. AST can be problematic to prescribe though, as not all compounding pharmacies make it. “If the pain has shifted toward the brain and there’s a central sensitization, you have to co-manage these patients with neurologists or pain specialists,” Dr. Hamrah said. “They have a variety of things [from] systemic medication to nerve blockers to acupuncture.” Preventive screening A key to understanding corneal neuralgia and preventing it from occurring in the first place is identifying the patients at risk. “I strongly believe that one of the significant risk factors is autoimmune disease,” Dr. Rosenthal said. Diseases to screen for include Sjogren’s syndrome, fibromyalgia, chronic interstitial cystitis, irritable bowel syndrome, chronic fatigue syndrome, and multiple chemical hypersensitivities. “One of the important parts in getting patient history is detailing any possible symptoms of autoimmune disease such as dry mouth. Go down the whole list,” Dr. Rosenthal said. “Is there family history of neuropathic pain elsewhere in the body?” In that case, one has to ask, should systemic pain disorders be a contraindication to refractive surgery? “Yes,” Dr. Rosenthal said. “Laser keratorefractive surgery is not treating a disease. If you’re dealing with a healthy tissue, then the complication rate should be zero. I’m sure this would exclude many people who could have done well. But patients should at least know about this risk. I’d say 90% of my [neuralgia] patients have thoughts of suicide. Just imagine, you open your eyes in the morning and you know the whole day you’re going to have tremendous pain. The despair is incredible.” Although this disease can be debilitating, it’s important to stress its rarity. Some patients with autoimmune disease may develop corneal neuralgia, but certainly not all. Corneal neuralgia may need further study before refractive surgeons begin to list autoimmune disease as a decisive contraindication for surgery. We do know enough about the disease, however, to say with absolute certainty that these patients aren’t crazy. “The most important thing is these patients aren’t dismissed,” Dr. Hamrah said. “Just because you can’t see it on the slit lamp doesn’t mean it’s not there. It’s important, if [patients have] symptoms, to send them to centers that have the capability of analyzing them further instead of just telling [them], ‘It’s nothing.’” EWAP Editors’ note: The doctors mentioned have no financial interests related to this article. Contact information Cason: john.cason@med.navy.mil Hamrah: pedram_hamrah@meei. harvard.edu Rosenthal: perry.rosenthal@comcast.net 025,$ 6 $ UXH *HRUJHV %HVVH $QWRQ\ )5$1&( 3KRQH )D[ PRULD#PRULD LQW FRP ZZZ PRULD VXUJLFDO FRP Corneal Transplant Disposable Surgical Instruments Universal chamber cover 7KH GHVLJQ RI WKH FRYHU LV FRPSDWLEOH ZLWK WKH FRQHV RI YDULRXV IHPWRVHFRQG ODVHUV DQG IDFLOLWDWHV WKH XVH RI LQVWUXPHQWV IRU PDQXDO GLVVHFWLRQ 2 ports with 2 stopcocks (LWKHU SRUW PD\ EH XVHG WR LQMHFW RU DVSLUDWH YLVFRHODVWLF FRUQHDO VWRUDJH PHGLXP %66 RU DLU EHQHDWK WKH GRQRU FRUQHD Perfect stability 7LJKWHQHG E\ D VFUHZ WKH DVVHPEO\ UHOLDEO\ SURWHFWV WKH GRQRU FRUQHD 7KH UXEEHU EDVH PDLQWDLQV WKH VWDELOLW\ RI WKH FKDPEHU User-friendly design 2SWLPDO VL]H DQG ZHLJKW ZLWK ZHOO WR UHWDLQ OLTXLG