Study of corneal topographic patterns with single continuous suturing techniques in penetrating keratoplasty

Purpose. To study the corneal topographic patterns following three different types of single continuous suturing techniques in penetrating keratoplasty. Methods. One hundred forty-eight maps obtained from 40 patients who underwent penetrating keratoplasty with single continuous suturing were retrospectively analyzed at a tertiary eye care center. The videokeratograph maps were obtained on the Eye Sys System 2000 at 1, 3, and 6 months after surgery. Suture adjustment was done for cases with astigmatism greater than 3 diopters, and maps were also obtained after suture adjustment. The maps were classified according to the corneal profile and the astigmatic pattern seen in the topographic maps. Results. Combined prolate patterns were seen most frequently, and their proportion was significantly higher at 1 month (p = 0.009), 3 months (p = 0.0004), and 6 months (p = 0.0008). The simulated keratometric astigmatism was significantly higher in the prolate group compared with the other groups at I month (p = 0.0021). However, all the topographic patterns showed comparable magnitude of astigmatism after suture adjustment and at 3 and 6 months. The antitorque suturing technique showed a higher proportion of prolate maps compared with the other suturing techniques. Conclusions. Prolate patterns of the cornea are the most frequently seen patterns after single continuous suturing, which is the normal physiological pattern of the cornea. The initial astigmatism is higher in the prolate pattern, which can be successfully reduced with suture adjustment.