Complications of combined radial thermokeratoplasty and incisional keratotomy

Purpose: To report complications of radial thermokeratoplasty (RTK) when used in combination with either radial keratotomy (RK) or astigmatic keratotomy (AK). Methods: RTK is a technique for the surgical correction of hyperopia and presbyopia. 600°C burns are applied to the peripheral cornea for 0.3 seconds using a specialized cautery probe. The thermal energy generated shrinks stromal collagen and flattens the peripheral cornea. The central cornea is steepened producing a myopic shift. Results: Two patients who had RTK in combination with either RK or AK are reported. Patient 1 was bilaterally hyperopic and presbyopic. The patient had RTK performed on the left eye in an attempt to make that eye myopic. The goal was to allow the left eye to be used for near vision. After RTK, the left eye was significanfiy overcorrected. The patient then had RK in the left eye which resulted in profound overcorrection with return of hyperopia. Postoperatively, examination revealed gaping of the RK incisions and poor epithelial wound healing. The patient also complained of severe ocular pain. Despite suturing the RK incisions, the eye remained hyperopic. The patient underwent two additional RTK procedures which failed to correct the induced hyperopia. The second patient had induced hyperopic astigmatism after undergoing RK. RTK was then performed to correct the hyperopia. However, the result was a worsening of the astigmatism. Two t-cut astigmatic keratotomies were then performed which improved the astigmatism but subsequently exacerbated the hyperopia. A second RTK procedure was then performed; however, it failed to correct the induced hyperopia. Conclusions: RTK is an unproved surgical technique for the correction of hyperopia and presbyopia that needs much further evaluation before broad clinical application can be supported.