comparison of reinnervation after various methods of corneal surgery

Refractive surgical procedures have been associated with a marked postoperative hypaesthesia. Measurement of corneal sensitivity was performed in order to assess the influence of various surgical techniques on postoperative reinnervation. Corneal sensitivity was examined with the Draeger aesthesiometer in eight patients after lamellar keratoplasty, seven patients after epikeratophakia and 82 patients after photorefractive keratectomy. Nine points on each cornea were examined. Corneal sensitivity after lamellar keratoplasty was normal one year after surgery. A correlation with the depth of the lamellar dissection was seen. Patients having lamellar keratoplasty with pterygium showed a decreased sensitivity in the nasal area of the lenticule and the nasal host cornea as much as one year after surgery. Three years after epikeratophakia the central cornea was still unsensitive. After photorefractive keratectomy in eyes with more than 10 D of myopia, a corneal hyposensitivity could be shown as much as two years after surgery. In other words, corneal refractive procedures may lead to a marked delay of reinnervation within the central cornea whatever surgical method is used

Lamellar keratoplasty with a new automatic rotary microkeratome: preliminary results

Techniques of lamellar dissection of the cornea have been proposed and publicized for more than a hundred years. Initial attempts at heterologous transplantations often proved discouraging, while subsequent use of homologous tissue greatly reduced immunological reaction and clouding of the transplant. With modern techniques of dissection, wound surfaces can be obtained that are smooth and not additionally optically active [plano]; this greatly improves visual results. Among the first 12 lamellar keratoplasties performed by us with our automatic microkeratome, 4 eyes with keratoconus had not quite reached their best corrected preoperative visual acuity at 4 months after surgery [mainly because of wrinkles in Descemet's membrane], while all other eyes [3 with status post-superficial chemical burn, 2 with recurrent pterygium affecting the center of the cornea, 2 after microbial ulcer and keratitis and 1 with epithelial dystrophy] surpassed their preoperative visual acuity, sometimes considerably. Patients' ages ranged from 13 to 65 years. Complications included interface problems in the eye of our oldest patient [recurrent pterygium], and disturbances in epithelial healing in two eyes - one with keratoconus, and one with epithelial dystrophy. Postoperative astigmatism reached a maximum of 3.0 diopters