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Purpose: To assess the safety of a laryngeal mask (i-gel) in keratoplasty performed under general anesthesia., Methods: Patients with indications for keratoplasty (n = 110) were enrolled in a prospective study and randomly assigned to the i-gel (n = 55; 30 lamellar keratoplasty and 25 penetrating keratoplasty) or tracheal tube group (n = 55; 29 lamellar keratoplasty and 26 penetrating keratoplasty). Perioperative complications and the recovery time were compared between the 2 groups using the t test or χ(2) test. Contraindications to elective use of the laryngeal mask airway (esophageal reflux, extreme obesity, oropharyngeal pathology, or expected difficult intubation) and expected difficult intubation were excluded., Results: No surgical perioperative complications were reported in either group. There was a significantly greater incidence of coughing at extubation and/or after extubation in the tracheal group (40/55; 73%) than in the laryngeal mask group (3/55; 5%) (P < 0.001). The recovery time was shorter in the i-gel group (80 minutes; 95% confidence interval, 75-86) compared with that in the tracheal tube group (88 minutes; 95% confidence interval, 82-95) (P = 0.03). There were no significant differences in the incidence of sore throat and hoarseness between both devices., Conclusions: The use of i-gel for keratoplasty under general anesthesia appears to be safe, reduces the risk of potential ocular hypertension during recovery, and saves recovery time.

Purpose: The purpose of this study was to evaluate the quality of femtosecond laser corneal trephination in eye bank eyes by histologic and ultrastructural investigation., Methods: We performed Z-shaped, tophat-shaped, and mushroom-shaped trephinations of swelled corneas from eye bank eyes using an Intralase FS60 system. The corneoscleral discs were fixed immediately after the laser procedure without removing the buttons. Thin and ultrathin tissue sections were examined by light and transmission electron microscopy., Results: Optical micrographs of the corneal tissue revealed that the femtosecond laser was efficient in producing Z-shaped, tophat-shaped, and mushroom-shaped dissections with reproducible high cut regularity. Investigations by transmission electron microscopy demonstrated that cut edges were of good quality devoid of thermal or mechanical damage of the adjacent tissues. However, cellular and collagenous nanometric debris was created by the laser. In the anterior stroma, they formed a layer of several microns in thickness residing on the terminated disrupted collagen fibers, whereas in the posterior stroma, they formed a thinner pseudomembrane running along the edges of the incision., Conclusions: Corneal trephination performed by the femtosecond laser preserves the ultrastructure of the disrupted collagen fibers. In edematous corneas, a layer of cellular and collagenic debris thicker in the anterior stroma and thinner in the posterior stroma runs along the edges of the incision obtained at a constant laser energy density.

Purpose: To identify changing trends in penetrating keratoplasties (PKs) performed at the Hotel-Dieu Hospital in Paris between January 1980 and December 1999 and to explain the reasons for the changes., Methods: We retrospectively reviewed 3,736 of the 3,836 PKs performed between January 1, 1980, and December 31, 1999, and classified them into diagnostic categories., Results: The most common indications for PK were keratoconus (28.8%), herpetic infections (10.9%), graft failures (9.9%), aphakic and pseudophakic corneal edema (9.9%), Fuchs' endothelial dystrophy (9.4%), and nonherpetic leucoma (7.7%). Other indications represented 23.4% of the cases. The incidence of aphakic and pseudophakic corneal edema progressively increased between 1980 and 1991, became the most frequent indication in 1991 (21.4%), and then progressively decreased. The annual number of PKs increased between 1980 and 1986, decreased between 1987 and 1997, and increased again after September 1997. The decrease was caused by both a shortage of corneal buttons, and, in 1987, the fear of transmitting diseases through corneal transplantation, particularly human immunodeficiency virus. Beginning in 1992, decreases were also associated with stringent governmental regulations of eye bank tissue., Conclusion: Changes in the incidence and management of corneal disorders were the primary factors leading to modifications of grafting until 1987. After 1987, corneal button shortage probably corresponded to the acquired immune deficiency syndrome epidemic. Governmental regulations of eye banking led to a severe corneal button shortage between 1992 and 1997. Despite an increase in the number of PKs performed after 1997, corneal buttons are still preferentially allocated to patients in whom there is a high probability of graft success.

Previous studies have demonstrated the potential use of microporous, biocompatible materials to improve the long-term stability of keratoprosthesis. To determine the factors that will influence corneal tissue ingrowth into biocompatible, microporous materials, we have compared three types of fluorocarbon polymers--Impra, Gore-Tex, and Proplast--after intrastromal implantation in rabbit corneas. Despite similar physicochemical structures, a great difference was observed in histologic and ultrastructural cross sections after 4- and 8-month follow-ups. For Gore-Tex, we observed extrusion of the implant and infiltration of necrotic and inflammatory cells. All implants of Proplast also led to significant corneal damage resulting in extrusion of the material. Through the use of electron and light microscopy and image analysis, this study demonstrates the presence of cell differentiation and collagen synthesis in the pores of the Impra implant. Apart from biocompatibility, this experiment demonstrates the influence of pore size, porous microorganization, and biomechanical factors on prosthetic corneal material. Only Impra offers satisfactory interface, allowing fibroblastic cells and neocollagen synthesis into its pores, and it can become transparent.