RESUMEN
PURPOSE: To report 5-year outcomes of ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) with a central graft thickness intended to be <100 µm. METHODS: This retrospective, consecutive, interventional case series included 354 eyes with endothelial decompensation due to various causes (Fuchs endothelial dystrophy, pseudophakic or aphakic bullous keratopathy, failed previous graft, herpetic endothelitis, or buphthalmos). Donor tissue was prepared using the microkeratome-assisted double-pass technique aiming at a graft thickness <100 µm. The Descemet membrane was stripped under air. The graft was delivered into the anterior chamber using the pull-through technique through a 3.2-mm clear corneal incision using a modified Busin glide. The best spectacle-corrected visual acuity (BSCVA), endothelial cell loss, graft survival rates, and immunologic rejection rates were evaluated. RESULTS: Follow-up data at 1, 2, 3, and 5 years after UT-DSAEK were collected from 214, 172, 147, and 105 eyes, respectively. After excluding eyes with comorbidities, BSCVA better than or equal to 20/20 was recorded in 36.3%, 37.4%, 46.4%, and 53.4% of eyes, respectively, whereas BSCVA better than or equal to 20/40 was documented in 95.5%, 95.3%, 96.0%, and 96.6% of eyes, respectively. The mean endothelial cell loss was 35.4%, 42.3%, 43.3%, and 52.3%; Kaplan-Meier graft survival probability was 99.1%, 96.2%, 94.2%, and 94.2%, and Kaplan-Meier cumulative probability of a rejection episode was 3.4%, 4.3%, 5%, and 6.9% at 1, 2, 3, and 5 years, respectively. CONCLUSIONS: UT-DSAEK grafts allow excellent 5-year outcomes, including BSCVA, endothelial cell density, and survival rates comparable with those recorded post-Descemet membrane endothelial keratoplasty, but with a higher immunologic rejection rate.
Asunto(s)
Queratoplastia Endotelial de la Lámina Limitante Posterior/métodos , Distrofia Endotelial de Fuchs/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Células , Lámina Limitante Posterior/cirugía , Endotelio Corneal/citología , Endotelio Corneal/trasplante , Femenino , Rechazo de Injerto/inmunología , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Agudeza Visual , Adulto JovenRESUMEN
PURPOSE: To evaluate the possibility of using the intrastromal corneal ring segments (ICRSs) previously implanted as a depth reference for performing pneumatic dissection in deep anterior lamellar keratoplasty (DALK). METHODS: The depth of placement of 2 symmetrical ICRSs placed in the superior and inferior midperipheral cornea of 4 eyes of 4 patients with keratoconus was measured by means of anterior segment optical coherence tomography. Because of irregular and/or high astigmatism, DALK using pneumatic dissection was performed in all eyes. The standardized procedure included the following: 1) Deep trephination of the recipient cornea outside the ICRSs (9 mm in diameter), aimed at facilitating the insertion and advancement of a dedicated cannula under the ICRS implant, just within its peripheral margin; 2) air injection for pneumatic dissection; 3) removal of about 80% of the anterior stroma; 4) perforation of the "big bubble" ceiling under viscoelastic protection and removal of its central 6 mm; and 5) suturing of a donor lamella of the anterior stroma obtained by microkeratome dissection using a 450-µm head and punched to a diameter of 9 mm. RESULTS: In all cases, the site for air injection was selected where the thickness of the stroma underlying the superior ICRS did not exceed 150 µm. Pneumatic dissection succeeded uneventfully in all eyes; postoperative best spectacle-corrected visual acuity was 20/20 in 3 of 4 eyes, whereas refractive astigmatism was less than 3 diopters in all cases. CONCLUSIONS: The presence of ICRSs facilitates gauging the depth of cannula insertion at the time of DALK, to succeed with pneumatic dissection.