[Results of corneal lenticule extraction for correction]. / Rezul'taty ekstraktsii lentikuly rogovitsy dlya korrektsii miopii srednei i vysokoi stepeni.

One of the main methods for correcting moderate and high myopia is corneal lenticule extraction. Ziemer is adding a new application to the FEMTO LDV Z8 platform - Lenticule CLEAR, designed to treat myopia by corneal lenticule extraction.Purpose - to study the safety and effectiveness of corneal lenticule extraction using the Ziemer LDV Z8 device for the correction of moderate and high myopia. MATERIAL AND METHODS: The prospective study included 24 patients aged 26.8±4.6 years (24 eyes) who underwent surgeries for moderate and high myopia on the Ziemer LDV Z8 device at the S.N. Fyodorov National Medical Research Center «MNTK «Eye Microsurgery¼ in January 2020. RESULTS: After correction of moderate and high myopia using the Ziemer LDV Z8 device, patients showed stable improvement in visual acuity one week after surgery, which remained throughout the postoperative period. Dynamic 1-month follow-up of patients operated on the Ziemer LDV Z8 platform for moderate and high myopia showed that the median value of uncorrected visual acuity one week after surgery was 0.9 [0.7; 1.0], and after one month - 1.0 [1.0; 1.0]. Patients operated on the Ziemer LDV Z8 platform had no intra- or postoperative complications, 79.2% of patients also had no loss of maximum corrected visual acuity. The mean corneal thickness before surgery was 555.9±28.2 µm, it significantly decreased to an average value of 464.8±26.9 µm one week after surgery (p<0.05). The cost of tissue was 17 microns per 1 diopter. CONCLUSION: The obtained results indicate the high effectiveness of the correction of moderate and high myopia using the Ziemer LDV Z8 device.

[SMILE keratorefractive surgery technique]. / Keratorefraktsionnaia tekhnologiia SMILE.

Small incision lenticule extraction (SMILE) keratorefractive surgery technique is a laser surgery alternative to common methods that doesn't require laser ablation of the cornea. Despite its novelty, SMILE technique has already demonstrated positive clinical results comparable to Photorefractive Keratectomy (PRK) and Laser-Assisted in Situ Keratomileusis (LASIK), which led to its widespread application in clinical practice. Compared with other keratorefractive techniques, SMILE has a number of distinct advantage including high biomechanical stability of the cornea, low risk of dry eye syndrome, absence of a corneal flap and associated complications, preservation of corneal epithelium. The article describes the most common SMILE modifications, its weak points and possible complications, as well as methods of additional correction of remaining ametropy.

[Effect of corneal refractive surgery on optical coherence tomography measurements]. / Vliianie keratorefraktsionnykh operatsii na pokazateli opticheskoi kogerentnoi tomografii.

The effect of significant changes in corneal power after refractive surgery on the parameters of optical coherence tomography (OCT) has not been sufficiently studied. PURPOSE: To study effects of corneal refractive surgery on optical coherence tomography (OCT) measurements in patients with moderate and high myopia. MATERIAL AND METHODS: OCT was performed in 62 patients (62 eyes) with myopia over 4 D before and one month after LASIK. The changes in 14 parameters of the thickness of the retina, ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) were analyzed. RESULTS: The mean refractive effect was 7.07±2.02 D (4.0 to 11.75 D). Postoperative changes in the parameters analyzed were insignificant, averaging not more than 1.3% of the baseline value with the exception of pRNFL thickness in the temporal quadrant (2.2%). Only six of the 14 parameters were statistically significant - retinal thickness in the central subfield and the inner nasal quadrant, average and minimum thickness of GCIPL, and pRNFL thickness (mean and in the temporal quadrant). Individual changes of the parameters in most patients did not exceed the error of method. CONCLUSION: In patients with moderate to high myopia, LASIK operation has only a slight effect on the OCT parameters of the retina and pRNFL. Only in patients with very high myopia, the decrease over 10 D in corneal refractive power creates an optical effect of increasing the average thickness of pRNFL and GCIPL by 2-3 µm. This should be taken into account when examining such patients for glaucoma.