Abstract
Purpose: :
To evaluate the incidence of macular oedema after penetrating keratoplasty in keratoconic eyes, without any preoperative CME risk factor, using OCT3.
Methods: :
40 eyes of 40 patients (mean age 34yrs +/- 9.9SD) with advanced (III-IV stadium) keratoconus, without macular pathologies, were selected for surgery. 20 eyes (group A) were submitted to PKP with surgical iridectomy and 20 eyes (group B) just to PKP with Atropine 1% drops postoperative therapy. All patients were submitted to OCT3 Stratus macular examination, before surgery, at 1, 3 and 6 months during the follow-up. In group A preoperative BSCVA was 0.24 +/- 0.17SD and in group B was 0.16 +/- 0.14SD. Preoperatively, the mean OCT central macular thickness was 149µm +/- 17SD in the group A and 147µm +/- 20SD in the group B.
Results: :
1 month postoperatively in group A the BSCVA was 0.52 +/- 0.21SD and in the group B was 0.47 +/- 0.28SD, and at 6 months in the group A the BSCVA was 0.80 +/- 0.20SD and in the group B was 0.74 +/- 0.18SD. At 1 month after surgery, the mean OCT macular thickness was 212µm +/- 73SD for the group A and of 207µm +/- 54SD for the group B; at 6 months, the mean OCT macular thickness was of 161µm +/- 25SD for the group A and of 157µm +/-21SD for the group B. One month after surgery, only 15% of the case series (3 patients: 2 of group A and 1 of group B) showed an increase in macular thickness for retinal oedema (mean: 288µm +/- 13.5SD); 3 months postoperatively, only one eye still showed macular oedema (up to 248 microns), and at 6 months postoperatively, no eyes showed macular thickness over 210µm.
Conclusions: :
OCT is a safe and valid non-invasive method for macular thickness evaluation in keratoconic eyes after PKP. In our study, macular oedema was greater in group A patients. Probably, this could be related to a greater postoperative inflammation due to the surgical iridectomy that seems to be the main risk factor for macular oedema, that gradually decrease during the follow-up.
Keywords: keratoconus • macula/fovea • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)