Abstract
Purpose :
Diabetic corneas have ultrastructural changes that can lead to dry eye, abnormal healing after trauma. The literature is sparse on the topic of Asian diabetics corneas with good Va and automated refractive keratometry readings. At our retina clinic in California, we retrospectively evaluated the keratometry readings of corneas of Diabetic patients in an Asian population. Are there external refractive or superficial keratometry differences in Asian Diabetic vs Asian Control eyes?
Methods :
Corneal topography was performed using TopCon KR-8000PA Auto Kerato-Refractometer (Oakland, NJ) on patients as part of the refractive screening prior to dilation for evaluation of diabetic retinopathy. Inclusion criteria: Va = 20/15 to 20/50. Recent HbA1c/FBS within 6 months of exam; Controls were patients without diabetes (nl FBS). Exclusion criteria: corneal scarring, LASIK, corneal surgery or previous macula laser.
Results :
Total of 38 pts:
17 DM, 21 C; 17M, 21F; Age 43-90yrs; Avg 65.6yrs±10.8
Asians 22 pts: 11M, 11F; Age: 43-90yrs; Avg 61.4yrs±10.5
9 DM - HbA1c: Range 6.1-7.7%, Avg 6.9%±0.61; FBS: Range 95-197mg/dL; Avg 136mg/dL±35
13 C - HbA1c: Range 5.5-6.0%, Avg 5.8%±0.18; FBS: Range 84-119mg/dL; Avg 99mg/dL±10
Non-Whites 27 pts: 12M,15F; Age: 43-90yrs; Avg 64.4yrs ±11.2
13 DM - HbA1c: Range 6-7.7%; Avg 6.73%±0.62; FBS: Range 87-197mg/dL; Avg 124.92mg/dL±33.07
14 C - HbA1c: Range 5.5-6.0%; Avg 5.84%±0.18; FBS: Range 84-119mg/dL; Avg 98.08mg/dL±10.39
For OS: Asian diabetics (ADM) have a median horizontal axis (HA) of 158° vs. Asians controls (AC) median 28° (p=0.02). Non-White diabetics (NWDM) have a median horizontal axis of 158° vs. Non-White controls (NWC) 28.5° (p=0.05).
Conclusions :
Abnormal collagen fibrils are noted within the cornea by ultra-structural exam in diabetic patients. The irregular astigmatism occurring in diabetic patients may be due to the abnormal collagen which may play a role in decreased vision for diabetics. Asian DM eyes have an astigmatic axis closer to 150° whereas Asian Control eyes have an astigmatic axis closer to 50°. This has implications for refractive and cataract surgery.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.