SUMMARY
Purpose:
To analyse visual acuity, refraction and videokeratography after pterygium surgery.
Methods:
Seventy four eyes with primary nasal pterygium were classified according to their length into three Groups: Group I -pterygium ≤ 2mm (25 patients), Group II - pterygium > 2mm < 3,5mm (31 patients) and Group III -pterygium > 3,5mm ≤ 4,6mm (18 patients). The patients underwent surgery for pterygium removal with free conjuntival autograft technique. Visual acuity, refraction and videokeratographic measurements were performed preoperative, one, three and six months after surgery.
Results:
a) Some optical alterations were observed in Groups II and III preoperatively, first, third and sixth months postoperatively: increasing in corneal curvature, reduction in keratometric astigmatism and, consequently, in refractional astigmatism with improvement in visual acuity; b) In Group I, regular topographic astigmatism predominated in all stages of this study. The same was observed in Group II, except on the first month after surgery when irregular topographic astigmatism predominated. In Group III predominated both regular and irregular topographic astigmatism.
Conclusions:
1) Patients with pterygium ≤ 2mm in length can receive optical correction even before surgery for pterygium removal is done, and those with pterygium > 2mm ≤ 4,6mm can only receive it one month after pterygium surgery; 2) The longer the pterygium, the greater is the keratometric astigmatism induced; 3) The longer the pterygium, the more irregular is the topographic astigmatism, even if the lesion was removed.
Key words:
Pterygium - surgery; astigmatism; visual acuity; keratometry; videokeratography