RESUMO
ABSTRACT We present a case of a patient complaining of monocular diplopia due to a decentered ablation after LASIK. The patient underwent a wavefront-guided retreatment, which resulted in an epithelial ingrowth complication. Additionally, the patient developed cataract, with cataract surgery requiring reliable biometric measurements. Therefore, we opted for corneal treatment and corneal surface regularization. Although we attempted to lift the flap and wash the interface initially, the procedure proved unsuccessful, thereby necessitating immediate flap amputation. Once the corneal surface was regularized in the seventh postoperative month, transepithelial photorefractive keratectomy was successfully performed to homogenize the ocular surface, thereby significantly improving the patient's corrected visual acuity and resolving monocular diplopia. The surface and corneal curvature stabilized by the fifth month after the procedure. Phacoemulsification was then performed along with the implantation of a toric monofocal lens, which was selected using an appropriate formula, resulting in an excellent uncorrected visual acuity.
RESUMO
Background Keratectasia after laser in situ keratomileusis (LASIK) is a rare but severe complication,which threatens the visual acuity and corneal strength.Corneal collagen crosslinking (CXL) is a new therapy that increases the security and decreases the risk of complication.However,the effectiveness and safety of LASIK-CXL is still need to be concerned.Objective This study was to evaluate the safety of LASIK-CXL for myopia and astigmatism with thin cornea.Methods A prospective cohort study was designed.A total of 128 eyes of 64 patients with thin corneal and myopic astigmatism enrolled in Beijing Tongren Eye Center from January 2014 to January 2015.The patients were assigned to LASIK group (74 eyes of 37 patients) and LASIK-CXL group (54 eyes of 27 patients).Refractive surgery was performed by Visumax femtosecond lasrer and VISX S4 excimer laser.Eyes of LASIK-CXL group applied accelerated CXL immediately after LASIK.The follow-up was 6 months.Manifest refraction,uncorrected (UDVA) and corrected distance visual acuity (CDVA),average keratometry values (AveK),anterior segment OCT (AS-OCT),corneal hysteresis (CH) and corneal resistance factor (CRF) were examined before and after operation.This research passed through Ethics Committee of Beijing Tongren Hospital.Results The spherical equivalent (SE) of the LASIK group and LASIK-CXL group were (-6.49 ±2.41)D and (-6.97 ±2.41) D before operation and decreased to (-0.68 ±0.88) D and (-0.75 ±0.94) D 6 months after operation.The UDVA (LogMAR) was 1.18±0.28 and 1.05±0.38 before operation and elevated to-0.06±0.09 and-0.03±0.186 months after operation in the LASIK group and LASIK-CXL group.The preoperative AveK values were (44.37 ±1.46) D and (44.47± 1.50)D in the LASIK group and LASIK-CXL group and reduced to postoperative (39.30±2.06) D and (38.66± 1.80) D.The preoperative SRI of LASIK group and LASIK-CXL group were 0.25 ±0.21 and 0.24±0.22,which increased to 0.29±0.24 and 0.28±0.24.The SAI values were 0.36±0.16 and 0.39±0.15 before operation,which increased to 0.57 ±0.31 and 0.75 ±0.376 months after operation,and the SAI value of the LASIK-CXL group was significantly higher than that of LASIK (F =10.220,P--0.002).CRF values of LASIK and LASIK-CXL were (8.44±1.44)mmHg and (8.63±1.35) mmHg in preoperation,which decreased to (5.74±1.31) mmHg and (6.25± 1.24) mmHg in postoperation.The result of LASIK-CXL was higher than that of LASIK (F=8.650,P =0.040).CH values were 8.78 ± 1.51 and 8.69 ± 1.62 in preoperation,which decreased to (7.23 ± 1.08) mmHg and (6.50±1.32)mmHg.The value of LASIK-CXL was lower than that of LASIK (F =5.860,P =0.017).The mean depth of demarcation line was (228.45±28.24) μm (range 165 to 310 μm) on OCT,which was presented in 45 eyes (81.82％) at 1 month in postoperation.Conclusions Accelerated CXL with FS-LASIK is effective and safe in improving visual acuity in myopic astigmatism patients with thin cornea,which also can increase the rigidity of the cornea.
RESUMO
Purpose: To compare optical and visual quality of implantable collamer lens (ICL) implantation and femtosecond laser in situ keratomileusis (F-LASIK) for myopia. Methods: The CRX1 adaptive optics visual simulator (Imagine Eyes, Orsay, France) was used to simulate the wavefront aberration pattern after the two surgical procedures for -3-diopter (D) and -6-D myopia. Visual acuity at different contrasts and contrast sensitivities at 10, 20, and 25 cycles/degree (cpd) were measured for 3-mm and 5-mm pupils. The modulation transfer function (MTF) and point spread function (PSF) were calculated for 5-mm pupils. Results: F-LASIK MTF was worse than ICL MTF, which was close to diffraction-limited MTF. ICL cases showed less spread out of PSF than F-LASIK cases. ICL cases showed better visual acuity values than F-LASIK cases for all pupils, contrasts, and myopic treatments (p<0.05). No statistically significant differences were found in contrast sensitivities between ICL and F-LASIK cases with -3-D myopia for both pupils for all evaluated spatial frequencies (p>0.05). For -6-D myopia, however, statistically significant differences in contrast sensitivities were found for both pupils for all evaluated spatial frequencies (p<0.05). Contrast sensitivities were better after ICL implantation than after F-LASIK. Conclusions: ICL implantation and F-LASIK provide good optical and visual quality, although the former provides better outcomes of MTF, PSF, visual acuity, and contrast sensitivity, especially for cases with large refractive errors and pupil sizes. These outcomes are related to the F-LASIK producing larger high-order aberrations. .
Objetivo: Comparar a qualidade óptica e visual da lente implantável de collamer (ICL) e da ceratomileuse in situ com laser de femtosegundo (F-LASIK) na correção de miopia. Métodos: O simulador visual de óptica adaptativa CRX1 (Imagine Eyes, Orsay, França) foi usado para simular o padrão de aberração de frentes de onda, depois de dois procedimentos cirúrgicos: implante de ICL e tratamento F-LASIK para -3 e -6 D. A acuidade visual em diferentes contrastes e sensibilidade ao contraste em 10, 20 e 25 ciclos/grau (cpd) foram medidos para pupilas de 3 e 5 mm. A função de transferência de modulação (MTF) e a função de espalhamento de ponto (PSF) foram calculados para a pupila de 5 mm. Resultados: A MTF do F-LASIK foi pior do que a do ICL, que estava perto da MTF do limite de difração. A ICL apresentou menor espalhamento do PSF do que o F-LASIK. ICL apresentou melhores valores da acuidade visual do que F-LASIK para todas as pupilas, contrastes e tratamentos miópicos (p<0,05). Não foram encontradas diferenças estatisticamente significantes na sensibilidade ao contraste entre ICL e F-LASIK de -3 D, para ambas as pupilas e quaisquer frequências espaciais avaliadas (p>0,05). Por outro lado, para -6 D, diferenças estatisticamente significativas na sensibilidade ao contraste foram encontrados para ambas as pupilas e todas as frequências espaciais avaliadas (p<0,05). Sensibilidade ao contraste foi melhor após o implante da ICL que após o F-LASIK. Conclusões: ICL e F-LASIK proporcionam uma boa qualidade óptica e visual, embora a ICL oferece melhores resultados de MTF, PSF, acuidade visual e sensibilidade ao contraste, especialmente para grandes erros de refração e tamanhos de pupila. Estes resultados estão relacionados ao procedimento F-LASIK que induz maiores aberrações ...