Avetisov K S, Yusef N Yu, Surnina Z V, Avetisov S E, Ndary M
Research Institute of Eye Disease, Moscow, Russia.
I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia.
Vestn Oftalmol. 2020;136(2):6-12. doi: 10.17116/oftalma20201360216.
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.
To assess the changes in CNF after various methods of microinvasive cataract surgery.
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 (K).
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.
Further research should be aimed at analyzing the long-term results of both microinvasive phacosurgery techniques and the «classical» extracapsular cataract extraction, which remains the method of choice in a number of clinical situations.
白内障超声乳化术引起的角膜神经纤维(CNF)潜在变化仍未得到充分研究。这一方向的研究需求由多种情况决定:角膜共焦显微镜在临床实践中的应用、存在各种成因角膜变化时进行超声乳化手术的需求、混合(飞秒激光辅助)超声乳化术中激光辐射可能产生的负面影响。
评估各种微创白内障手术后CNF的变化。
对50至60岁接受标准超声乳化术和混合超声乳化术的患者进行研究;患者分别分为两组(每组30例手术)。评估CNF状态的算法包括使用原始软件的激光共焦显微镜检查。为了量化神经状态,使用了两个系数:CNF方向各向异性(KΔL)和CNF方向对称性(K)。
无论手术技术如何,均观察到方向各向异性系数降低、方向对称性系数增加的趋势,这与先前确定的CNF年龄相关变化具有条件可比性。混合超声乳化术后,干预后2 - 2.5个月方向各向异性系数的降低在统计学上比标准超声技术更不显著。
进一步的研究应旨在分析微创超声乳化手术技术和“经典”囊外白内障摘除术的长期结果,囊外白内障摘除术在许多临床情况下仍是首选方法。