Abstract
Purpose: :
Examination of perioperative changes in corneal higher order aberration (HOA) of eyes with pterygium.
Methods: :
Eight eyes of 8 patients (mean age, 70.5 yrs) who underwent pterygium excision at Kanazawa Medical University Hospital from November 2008 to August 2009 were followed up over three months. Pterygium surgery with conjunctival autograft was performed in all 8 cases where growth covered over one-third of the area of the cornea. Corneal HOA was measured by KR-9000PW (TOPCON) and evaluated with a component map.
Results: :
Preoperative mean aberrations (RMS, 6mm pupil diameter) of corneal total HOA (T-HOA), trefoil, coma and spherical were 3.246µm, 2.355µm, 1.219µm and 0.256µm respectively. The values of T-HOA, trefoil and coma had decreased significantly two weeks following surgery to 0.877µm, 0.428µm and 0.402µm, but there were no further significant decreases in respective mean aberrations. However, postoperative T-HOA, trefoil and coma aberrations remained markedly higher than those of normal volunteers. There was no remarkable perioperative change in spherical aberration.
Conclusions: :
Corneal HOA is prominently manifested due to pterygium, and its major components are trefoil and coma. HOA of eyes with pterygium is decreased significantly two weeks after surgery, with no subsequent change, yet remains much higher than that of normal eyes. It was clarified that corneal shape in eyes with pterygium stabilizes within two weeks postoperatively which suggests possibility of error mitigation of power calculation of IOL for cataractous eyes occurring with pterygium.
Keywords: pterygium • aberrations