Changes of the anterior, posterior corneal surface and total cornea high order aberrations after SMILE or ICL correction for low and moderate myopia / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To compare and analyze the changes of the anterior corneal surface, posterior surface and total corneal high-order aberration between femtosecond small incision lenticule extraction(SMILE)and implantable collamer lens(ICL)in the correction of moderate and low myopia. <p>METHODS: Retrospective Study. Patients underwent SMILE surgery(<i>n</i>=35)or ICL surgery(<i>n</i>=35)with moderate or low myopia were selected in the refractive center of the Xi'an Aier Eye Hospital from November 2017 to February 2018. Before and 1, 3 and 6mo after surgery, the Scheimpflug phase formation based on Ray Tracing technology was applied to evaluate the anterior corneal surface, posterior surface and total corneal high-order aberration with a diameter of 6mm. Repeated measurement ANOVA was used to analyze the mean square root of corneal coma, spherical aberration and total high-order aberration at different time points. <p>RESULTS: The post-surgery uncorrected visual acuity of both the SMILE group and the ICL group at 1, 3, and 6mo reached or exceeded the pre-surgery best corrected visual acuity, and the pre-surgery corneal aberrations of the two groups were not statistically significant(<i>P</i>>0.05). One month after surgery, the precorneal high-order aberration of the SMILE group was significantly increased(<i>P</i><0.05), while the precorneal high-order aberration of the ICL group was unchanged(<i>P</i>>0.05). Post-corneal aberration of the two groups was not statistically significant(<i>P</i>>0.05). After surgery, and the differences of coma, spherical aberration and total high-order aberration between the two groups were not significantly(<i>P</i>>0.05). <p>CONCLUSION: Compared with SMILE surgery, precorneal high-order aberration induced by ICL is less for moderate and low myopia in the short term.

Consistency of two eye anterior segment analysis systems measuring wave-front aberration before and after refractive surgery / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To study the consistency of pre-operative and postoperative wave-front aberration between SCHWIND and SIRIUS eye anterior segment analysis system. <p>METHODS: Prospective control study. A total of 360 eyes of 180 patients with refractive errors in West China Hospital of Sichuan University were selected. The data, including the degree and the direction of the flat axis and the steep axis, Kappa angle and a variety of high order wave-front aberrations, were measured by SCHWIND and SIRIUS anterior segment analyzers. The average value of each parameter was taken 5 times, and paired sample <i>t</i> test was used and the data was analyzed by SPSS22.0 software. <p>RESULTS: Flat axis degree and direction, steep axis degree and direction, coma, and trefoil were measured preoperatively and 1mo postoperatively by SCHWIND and by SIRIUS eye anterior segment analysis systems, and there were no statistically significant differences between the two machines(<i>P</i>>0.05). Kappa angle was measured 1mo postoperatively and there was no statistically significant differences(<i>P</i>>0.05). There was statistically significant difference(<i>P</i><0.01)preoperatively between two machines of high-order aberrations and spherical aberration(SpAb); values measured by SCHWIND were higher than those measured by SIRIUS. There was no statistically significant difference(<i>P</i>>0.05)between two machines of high-order aberrations or SpAb in 1mo postoperatively. <p>CONCLUSION: SCHWIND and SIRIUS anterior segment eye analysis system have a good consistency of wave-front aberration measurement before and after refractive surgery.

Resultados de la calidad visual óptima en pacientes operados de catarata en el Instituto Cubano de Oftalmología “Ramón Pando Ferrer” 2009 / Results of the optimal visual quality in patients operated on from cataract at “Ramon Pando Ferrer” Cuban Institute of Ophthalmology in 2009

Objetivo: Valorar los resultados de la calidad visual óptima en pacientes operados de catarata teniendo en cuenta la aberración ocular como factor determinante. Métodos: Se realizó un estudio observacional, longitudinal y prospectivo de las modificaciones aberrométricas (medidas por el OPD Scan II Nidek) en la cirugía de catarata desde enero a julio de 2009 en el Servicio de Microcirugía Ocular en el Instituto Cubano de Oftalmología “Ramón Pando Ferrer”. De un universo de 353 pacientes, se utilizaron 300 ojos operados de catarata pertenecientes a 220 pacientes. Todos fueron intervenidos quirúrgicamente por un mismo cirujano y con una misma técnica quirúrgica (Facoemulsificación). Las variables estudiadas fueron: mejor agudeza visual corregida preoperatoria y posoperatoria, función de transferencia modular, índice de Strehl, wave front error, test de sensibilidad al contraste, aberraciones corneales internas y totales, preoperatorias y posoperatorias. Agrupamos los resultados en tablas con frecuencias absolutas y relativas, usamos métodos estadísticos confiables. Resultados: La mejor agudeza visual corregida mejoró 4,5 líneas en la escala de Snellen. Hubo un incremento del valor función de transferencia modular y el índice de Strehl; mientras que el wave front disminuyó. Se incrementaron las aberraciones internas y totales. Las aberraciones corneales no se modificaron significativamente. Conclusión: Los pacientes incluidos en este estudio obtuvieron una calidad visual física acorde a los resultados biológicos encontrados. Elemento que avala la necesidad de efectuar dichas mediciones sistemáticamente de manera que siempre, se logre la mayor perfección visual que le aporte al paciente una vida social útil.

Objective: To assess the results of good visual quality in patients operated on from cataract, taking ocular aberration as a decisive factor. Methods: A prospective, observational, and longitudinal study of aberrometric modifications (measured by the OPD Scan II Nidek) in the cataract surgeries performed from January to July 2009 at the Ocular Microsurgery Department in “Ramón Pando Ferrer" Cuban Institute of Ophthalmology. Of the universe of 353 patients, 300 eyes operated from cataract from 220 selected patients were used. All the cases were surgically treated by the same surgeon who used the same technique called phacoemulsification. The variables under study were best corrected visual acuity pre and postoperative, Function of modular transfer, Strehl’s, wave front error, sensitivity on contrast test, and internal and total corneal aberrations and before and after surgery. The results were shown in charts with absolute and relative frequencies based on reliable statistical methods. Results: The best corrected visual acuity improved 4,5 lines in the Snellen’s chart. The values of function of modular transfer and the Strehl’ index increased but the wave front diminished. The internal and the total aberrations increased but the corneal aberrations did not change significantly. Conclusions: The patients included in this study obtained a quality visual in agreement physics to the opposing biological results, element that endorses the necessity to make this mensurations systematically so that the biggest visual perfection is always achieved that contributes the patient an useful social life.

Comparison of higher-order aberrations between implantations of AcrySof and AcrySof ReStor multifocal aspherical intraocular lens / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To compare the higher-order aberrations between implantations of AcrySof and AcrySof ReStor multifocal aspherical intraocular lens(IOL) with various pupil diameters.METHODS:Fifty-four patients(62 eyes)with bilateral senile cataracts were retrospectively selected.Patients were operated with phacoemulsification and IOL implantation.They were divided into two groups based on the IOL implantation of AcrySof IQ and AcrySof ReStor.Wave front aberration:spherical aberration(C12)and the root mean square of the total higher-order aberration(RMSh)were observed 3 months after surgery.RESULTS:The larger the pupil was, the higher the C12 and RMSh were in the eyes (P<0.01).There were no statistical differences in C12 or RMSh between two groups at 5, 6 or 7mm pupil diameters (P>0.05). CONCLUSION:There are no differences between AcrySof IQ group and AcrySof ReStor group at 5, 6 or 7mm pupil diameters.

The effects of Ortho-K contact lens by day and overnight wear on wave-front aberrations / 眼科

Objective To investigate the change of wave-front aberrations after Ortho-K contact lens(CL)by day and overnight wear.Design Retrospective case series.Participant 180 eyes of 92 myopic patients wearing Ortho-K CL.Method Wave-front aberra- tions of 180 eyes of 92 myopic patients wearing Ortho-K CL were analyzed.Patients were divided into by day wear and overnight wear groups.Wave-front aberrations were measured with WFA 1000B subjective aberrometer before and 1 month after Ortho-K CL wear. Wave-front aberrations at initial,after one month of CL fitting and without CL were measured in same condition,and RMS values for overall wave-front aberrations and each order of the Zernike aberrations were analyzed with Matlab software.Main Outcome Measures RMS value of Zernike coefficient of each order.Result Compared with initial aberration in wear by day group,total RMS and each or- der aberrations(except 2nd order)with lens fitting significantly increased(P0.05).Compared with initial aberration in overnight wear group,overall wavefront aberrations and the RMS(except 2nd,3rd and 6th order Zernike aberrations)with lens fitting significantly increased(P0.05).Conclusion The high order aberrations with lens fitting and without lens fit- ting increased in each group.The aberration with lens fitting in wear by day group was higher than that in overnight wear group,while the aberration without lens fitting in overnight wear group was higher than that in wear by day group.(Ophthalmol CHN,2007,16: 351-354)

Position-induced Cyclotorsion under Monocular Fixation

PURPOSE: To determine whether cyclotorsion occurs when a patient moves from the seating to supine position fixating with one eye. METHODS: The axis of astigmatism was measured with the handheld automated refractometer (Retinomax K-plus, Nikon, Japan) in 33 eyes having more than -1.0D cylinder in seated and supine positions under monocular fixation. RESULTS: There was a cyclotorsional deviation in 30 eyes (90.90%). Excyclotorsion was shown in 22 eyes (66.67%) and incyclotorsion in 8 (24.24%). Seventeen eyes (51.50%) had a torsional deviation less than 4 degrees, 5 eyes (15.15%) from 5 to 6 degrees, 7 eyes (21.21%) from 7 to 14 degrees and one eye greater than 15 degrees. CONCLUSIONS: Positionally induced cyclotorsion occurs under fixation with one eye simulating refractive surgery. Surgeons should therefore make an effort to align the wavefront measurement to the ablation onto the cornea.

Comparison of Wave-front Guided LASIK and Conventional LASIK

PURPOSE: To evaluate the effectiveness of wave-front-guided LASIK in reducing the increase of high order aberration, we compared the aberrational change and other clinical outcomes after LASIK by the conventional method and those by wave-front guided ablation. METHODS: 50 eyes of 25 patients were included. In one eye, conventional LASIK was performed (group1), then in the other eye, wave-front guided LASIK was performed (group2). Patient's optical aberrations were measured with Zywave(R) (Bausch and Lomb Surgical), Shack-Hartmann type of aberrometer. We then compared high order aberrations, contrast sensitivity, visual acuity, topographic result, and manifest refraction, preoperatively and postoperatively after 1 and 3 months. RESULTS: Uncorrected visual acuity improved to more than 20/20 in 2 eyes of group 1 and in 5 eyes of group 2. In group 1, RMS(H) were 0.235 preoperatively and 0.594 and 0.429 postoperatively after 1 and 3 month. In group 2, RMS(H) were 0.285, 0.442 and 0.353.Contrast sensitivity in the mesopic condition of the wave-front guided LASIK group was higher than that of the conventional ablation group. But this change was not statistically significant. CONCLUSIONS: The wave-front guided wave-front guided LASIK showed slightly better outcome than that of the conventional ablation in postoperative visual acuity, and contrast sensitivity in mesopic condition.