Résumé
Aims: The aim of this study is to compare corneal parameters in: central corneal thickness (CCT), thinnest corneal thickness (TCT), mean radius of curvature (Rm) and anterior chamber depth (ACD) obtained from Pentacam Schiempflug and OCT Tomography imaging which are checked preoperatively and six months postoperatively after LASIK surgery.Methodology: Our sample consisted of 40 eyes. Changes in corneal dimensions were monitored before and after LASIK surgery using scheimpflug tomography (Pentacam HR) and optical coherence tomography (OCT). The parameters measured were CCT, TCT, Rm and the ACD. The results between the two techniques were compared with the Bland-Altman method.Results: During the analysis of the results, a statistically significant difference was observed between the two techniques in terms of the preoperative CCT as well as the TCT both preoperatively and postoperatively.Scheimpflug tomography gives higher values of the CCT than OCT, up to thickness 530nm, while above this it seems that OCT overestimates the thickness of the cornea. Scheimpflug tomography at the TCT seems to give higher values than OCT tomography, up to thickness 520 nm, while above that it seems that OCT tomography overestimates TCT. We have similar results postoperatively for TCT.The two techniques agree on the ACD and the Rm rating.Conclusion: How converging or different the two imaging devices are because it is important for both clinical practice and research may be a point of reference for starting a new research.
Résumé
Resumo Descrição de relato de caso de paciente com ceratocone (KC), Distrofia Endotelial de Fuchs (DEF) e catarata concomitantes com descompensação corneana submetido a Ceratoplastia Lamelar Posterior pela técnica Descemet's Membrane Endothelial Keratoplasty (DMEK) associado a facoemulsificação com implante de lente intraocular (LIO). Observou-se aplanamento corneano significativo no pós-operatório e acuidade visual final sem correção de 20/25 . Destaca-se a possibilidade do DMEK como alternativa à Ceratoplastia Penetrante (Penetrating Keratoplasty - PK) em casos de DEF e KC associados. Aplanamento corneano pode ocorrer neste grupo de pacientes, o que pode resultar em imprevisibilidade refracional no cálculo do poder da LIO ao se optar por facectomia combinada. Neste relato, apesar da modificação da curvatura corneana após cirurgia combinada de DMEK com facectomia, a acuidade visual final sem correção foi satisfatória, demonstrando a possibilidade de sucesso desta abordagem na coexistência de DEF, KC e Catarata. Entretanto, a possibilidade de mudança significativa na curvatura corneana deve ser considerada em pacientes com KC, edema de córnea secundário a DEF e catarata, na decisão de cirurgia simultânea ou em dois tempos.
Abstract This is a case report of a patient with concomitant Keratoconus (KC), Fuchs Endothelial Dystrophy (FED) and cataract with corneal decompensation submitted to Posterior Lamellar Corneal surgery (Descemet's Membrane Endothelial Keratoplasty - DMEK) associated with phacoemulsification with intraocular lens (IOL) implantation. Corneal flattening and uncorrected visual acuity of 20/25 was observed in the postoperative period. We reasure the viability of DMEK as an alternative to Penetrating Keratoplasty (PK) in cases of associated DEF and KC associated. Changes in corneal curvature may occur in this group of patients and lead to the possibility of refractive unpredictability in IOL calculation when performing a combined cataract surgery. Despite unexpected corneal flattening, satisfactory final visual acuity was achieved, demonstrating the possibility of success of this approach in the coexistence of the three conditions. Nonetheless, the possibility of corneal curvature changes should be considered in patients with KC and corneal decompensation due to FED in decision making, regarding simultaneous or sequential surgical approach.