RESUMEN
The question of potential changes in the nerve fibers of the cornea induced by phacosurgery remains poorly investigated. This is a review of results of many individual studies aimed at assessing the condition of corneal nerve fibers following different techniques of cataract removal. The authors substantiate the necessity for structural analysis of fiber changes based on in vivo confocal microscopy of the cornea. Functional assessment of corneal sensitivity (esthesiometry) does not allow objective conclusions, for several reasons. Further studies on corneal nerve changes after phacosurgery could be directed at improving software products for objective quantitative assessment of corneal nerve fibers and analyzing long-term results of various phacosurgery techniques.
Asunto(s)
Extracción de Catarata , Córnea , Córnea/diagnóstico por imagen , Córnea/cirugía , Microscopía Confocal , Fibras NerviosasRESUMEN
INTRODUCTION: Potential changes in corneal nerve fibers (CNF) induced by cataract phacoemulsification remain insufficiently studied. The need for research in this direction is dictated by a number of circumstances: introduction of corneal confocal microscopy into clinical practice, the need for phaco surgery in the presence of corneal changes of various genesis, the possible negative impact of laser radiation during hybrid (femtosecond laser-assisted) phacoemulsification. PURPOSE: To assess the changes in CNF after various methods of microinvasive cataract surgery. MATERIAL AND METHODS: The studies were conducted in patients aged 50 to 60 years who underwent standard ultrasound and hybrid phacoemulsification; the patients were respectively divided into two groups (30 surgeries each). The algorithm for assessing the state of CNF involved laser confocal microscopy using original software. To quantify the state of the nerves, two coefficients were used: CNF orientation anisotropy (KΔL) and CNF orientation symmetry (Ksym). RESULTS: Regardless of the surgery technique, tendencies were noted for the orientation anisotropy coefficient to decrease and the orientation symmetry coefficient to increase, which are conditionally comparable with previously identified age-related changes in CNF. After hybrid phacoemulsification, a decrease in the orientation anisotropy coefficient 2-2.5 months after the intervention turned out to be statistically less significant compared to the standard ultrasound technique. CONCLUSION: Further research should be aimed at analyzing the long-term results of both microinvasive phacosurgery techniques and the «classical¼ extracapsular cataract extraction, which remains the method of choice in a number of clinical situations.