Corneal and refractive surgery

Classification: (a) partial (anterior or posterior lamellar) or (b) full-thickness (penetrating [PKP]).

Indications: (a) optical, (b) tectonic, (c) therapeutic, and (d) cosmetic.

Donor tissue: should be removed within 12–24 hr of death and stored under special conditions; contraindications to donation include certain infections (e.g. HIV) and some forms of ocular disease.

Technique: (a) determination of graft size, (b) trephination of donor tissue, (c) excision of host tissue, and (d) fixation of donor button ( Fig. 7.1 ); postoperative topical steroids and cycloplegics.

Early postoperative complications: (a) persistent epithelial defect, (b) wound dehiscence, (c) uveitis, (d) elevation of intraocular pressure, (e) endophthalmitis, and (f) fixed dilated pupil (Urrets–Zavalia syndrome).

Late complications: (a) astigmatism, (b) recurrence of disease in graft, (c) wound separation, (d) retrocorneal membrane formation, (e) glaucoma, and (f) cystoid macular oedema.