Corneal biomechanics in age‐related macular degeneration

Abstract

Abstract Purpose To compare the corneal hysteresis (CH) and the corneal resistance was increase force (CRF) of patients with age‐related macular degeneration (ARMD) and control subjects. Methods The CH and the CRF were compared among 20 patients with ARMD (ARMD group: 10 with neovascular and 10 with non‐neovascular ARMD) aged from 54 yrs to 78 yrs (68.9±15.9 yrs) and 20 age‐matched control patients (control group). In ARMD and control group the eye's axial length was: 23.14 ±0.95 mm vs. 23.04 ±1.16 mm (p<0.715) and the corneal thickness was: 555.1±3.08 vs. 558±4.14 µ (p<0.274). The CH and CRF values were achieved by ocular response analyzer (ORA). Results We found a statistical significant difference in the CRF between patients with ARMD and control subjects (ARMD group 11.13±1.30 vs. control group: 9.82±1.37; p<0.001) was found. A difference, but no stastical significant was found also for CH index between patients with AMD and control subjects (ARMD group: 10.15±1.25 vs. control group: 10.02±1.68 mm/hg; p<0.376). When we examined separately the two subgroups of patients with ARMD (neovascular and nonneovascular ARMD), the average CH were higher in patients with neovascular AMD compared with patients with non‐neovascular ARMD (neovascular ARMD group: 10.77±1.00 vs. non‐neovascular ARMD 10.17±1.08; p<0.074) and CRF was also increased in neovascular ARMD (neovascular ARMD group: 11.86±0.99 vs. non‐neovascular ARMD 10.88±1.37; p<0.032). Conclusion Despite the limitations placed by the small sample of the examined cases, patients with ARMD had a statistical significant increase of CRF compared with healthy control group. Furthermore we found the same statistical significant increase of CRF in neovascular ARMD patients compared with non‐neovascular ARMD