In 2014, the Centers for Disease Control and Prevention reported a prevalence of 12.3% for diabetes mellitus in US adults aged 20 years and older—about 28.9 million people. A patient with diabetes mellitus who is considering refractive surgery should have a thorough preoperative history and examination, and the surgeon should pay special attention to the presence of active diabetic ocular disease. The blood sugar of a diabetic patient must be well controlled at the time of examination to ensure an accurate refraction. A history of laser treatment for proliferative diabetic retinopathy or cystoid macular edema indicates visually significant diabetic complications that typically contraindicate refractive surgery. Ocular examination should include inspection of the corneal epithelium to check the health of the ocular surface, identification of cataract if present, and detailed retinal examination. Preoperative corneal sensation should be assessed because corneal anesthesia can impede epithelial healing.
A retrospective review 6 months after LASIK in 30 eyes of patients with diabetes mellitus revealed a complication rate of 47%, compared with a complication rate of 6.9% in the control group. The most common problems in this study were related to epithelial healing and included epithelial loosening and defects. A loss of 2 or more lines of BCVA was reported in less than 1% of both the diabetes mellitus and control groups. However, 6 of the 30 eyes in the diabetes mellitus group required a mean of 4.3 months to heal because of persistent epithelial defects. The authors concluded that the high complication rate in these patients was explained by unmasking subclinical diabetic keratopathy.
Another retrospective review of 24 patients with diabetes mellitus who underwent LASIK demonstrated that 63% achieved UCVA of 20/25 or better. Three of the 24 eyes had an epithelial defect after surgery, and epithelial ingrowth developed in 2 of these eyes. No eye lost BCVA. In contrast, Cobo-Soriano and colleagues evaluated 44 diabetic patients (both insulin-dependent and non–insulin-dependent) who underwent LASIK in a retrospective, observational, case-controlled study and reported no significant difference in perioperative and postoperative complications, including epithelial defects, epithelial ingrowth, and flap complications between diabetic patients and control subjects.
In light of these contradictory reports, refractive surgeons should exercise caution in the selection of patients with diabetes mellitus for refractive surgery. Intraoperative technique should be adjusted to ensure maximal epithelial health. To reduce corneal toxicity, the surgeon should use the minimal amount of topical anesthetic (preferably in the form of nonpreserved drops) immediately before performing the procedure. Patients with diabetes mellitus should be counseled preoperatively about the increased risk of postoperative complications and the possibility of a prolonged healing time after LASIK. They should also be informed that the procedure treats only the refractive error and not the natural history of the diabetes mellitus, which can lead to future diabetic ocular complications and associated vision loss.
Centers for Disease Control and Prevention. National Diabetes Statistics Report: Estimates of Diabetes and Its Burden in the United States, 2014. Atlanta, GA: U.S. Department of Health and Human Services; 2014.
Cobo-Soriano R, Beltrán J, Baviera J. LASIK outcomes in patients with underlying systemic contraindications: a preliminary study. Ophthalmology. 2006;113(7):1118.e1–e8.
Fraunfelder FW, Rich LF. Laser-assisted in situ keratomileusis complications in diabetes mellitus. Cornea. 2002;21(3):246–248.
Halkiadakis I, Belfair N, Gimbel HV. Laser in situ keratomileusis in patients with diabetes. J Cataract Refract Surg. 2005;31(10):1895–1898.
Jabbur NS, Chicani CF, Kuo IC, O’Brien TP. Risk factors in interface epithelialization after laser in situ keratomileusis. J Refract Surg. 2004;20(4):343–348.
Excerpted from BCSC 2020-2021 series: Section 13 - Refractive Surgery. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.