Analysis of efficacy and safety of patients after LASIK surgery in 20 years / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate long-term efficacy and safety of patients after excimer laser in situ keratomileusis(LASIK)surgery in 20a.METHODS: A retrospective study.Patients who underwent LASIK in our hospital from January 1998 to December 2001 were recruited. The patients were notified by telephone to the outpatient for follow-up. The collected data included demographic characteristics(gender and age), preoperative uncorrected distance visual acuity(UCVA)and best corrected visual acuity(BCVA), preoperative diopter, intraoperative corneal flap thickness and corneal stromal residual thickness(RST). The main indicators were long-term efficacy index, safety index, UCVA, BCVA, corneal thickness and axial length. The slit lamp, fundus and optical coherence tomography(OCT)examination were performed at the same time.RESULTS: A total of 95 patients(190 eyes)were recruited. At the final postoperative visit, there were 71 patients(142 eyes, 74.7%)had UCVA≥1.0, and 82 patients(164 eyes, 86.3%)had BCVA≥1.0. There were 2 eyes among them had bad BCVA(≤0.6)due to macular retinoschisis and glaucoma, respectively, while other patients' BCVA was 0.8. There was no significant correlation between the UCVA and BCVA of patients after surgery in 20a and the factors such as age at surgery, preoperative diopter and corneal thickness(P>0.05), but there was a negative correlation with the increase of axis length(rs=-0.32, -0.31, all P<0.05). UCVA and BCVA were positively correlated with corneal stromal residual thickness at the last postoperative follow-up(P<0.05). The safety and efficacy indexes of LASIK after surgery in 20a were 1.00±0.10 and 0.83±0.27, respectively. During the follow-up, no patients were found to have corneal ectasia and complications related to corneal flap, and no patients underwent secondary surgery. No patients with corneal dryness were found after silt lamp examination.CONCLUSION: LASIK after surgery in 20a shows good safety and efficacy.

Uso de adhesivo tisular de fibrina en el tratamiento de endocrecimiento epitelial severo posterior a Lasik. Reporte de caso / Use of fibrin tissue adhesive in the treatment of severe epithelial ingrowth after LASIK. Case Report

Objetivo: Describir el uso de adhesivo tisular de fibrina para el sellamiento del flap en el tratamiento de un paciente con endocrecimiento epitelial severo posterior a Laser In Situ Keratomileusis (LASIK). Diseño: Reporte de caso. Metodología: Reporte de Caso retrospectivo, mediante la recopilación de datos clínicos, imágenes, video y valoraciones postoperatorias. Resultado: Se reporta el uso de adhesivo tisular para el sellamiento del flap en el tratamiento de un paciente con endocrecimiento epitelial severo bilateral posterior a LASIK. Se documenta la recuperación de la agudeza visual en el ojo izquierdo (el ojo tratado) posterior a el uso de adhesivo tisular de fibrina para el sellamiento del flap en el tratamiento del endocrecimiento epitelial severo posterior a LASIK, llegando a una visión mejor corregida de 20/30. Conclusión: Se han descrito varias opciones de manejo: remoción mecánica junto con adhesión del flap mediante sutura, cianoacrilato, adhesivo tisular de fibrina o hidrogel. En la literatura mundial hay publicaciones de casos sobre el uso de adhesivo tisular de fibrina con buenos resultados, hasta la fecha este es el primer caso reportado en nuestro país, siendo demostrativo de buenos resultados, en cuanto a la tasa de recidiva y agudeza visual.

Purpose: To describe the use of fibrin adhesive for flap sealing in the treatment of a patient with severe epithelial ingrowth following Laser In Situ Keratomileusis (LASIK). Design: Case Report. Methods: Retrospective Case Report study, was performed by collecting clinical data, images, video and postoperative evaluations. Results: The use of tissue adhesive for flap sealing is reported in the treatment of a patient with severe bilateral epithelial ingrowth post-LASIK Subsequent recovery of the visual acuity in the left eye (treated eye) after the use of fibrin adhesive for fl ap sealing in the treatment of severe epithelial post-LASIK epithelial ingrowth, reaching a better-corrected vision of 20/30. Conclusion: Several management options have been described: mechanical removal along with flap adhesion by suture, cyanoacrylate, fibrin adhesive or hydrogel. In the world literature there are case reports on the use of fibrin adhesive with good results, to date this is the fi rst case reported in our country, demonstrating good results in terms of relapse rate and visual acuity.

Clinical Outcomes of Combined Procedure of Astigmatic Keratotomy and Laser in situ Keratomileusis

PURPOSE: To evaluate the clinical outcomes of a combined procedure of astigmatic keratotomy (AK) and laser in situ keratomileusis (LASIK) for the correction of high astigmatism. METHODS: Thirty-five eyes of 19 patients who had astigmatic keratotomy were studied. The patients had a secondary procedure, LASIK, to correct the residual refractive error. Follow-up visits were at 1 week, 1 month, 3 months, and 6 months. The outcome measures included uncorrected distance visual acuity, refractive error, efficacy, safety, and predictability. We compared preoperative and post-AK expected corneal ablation depth using an Amaris Ablation depth table. RESULTS: After astigmatic keratotomy, astigmatism was reduced by 61.43 ± 14.62%, and after LASIK, astigmatism was reduced by 91.65 ± 8.68%. Expected corneal ablation depth was reduced by 18.72 ± 11.77% after astigmatic keratotomy. The proportion of eyes with spherical equivalent 0.5 D or less was 85.71% at 6 months after the combined procedure of astigmatic keratotomy and LASIK. No intraoperative or postoperative complications were observed. CONCLUSIONS: This study showed the combined procedure of astigmatic keratotomy and LASIK is effective for visual acuity, refraction, and reduction in corneal ablation depth.

Comparison of 10-year Clinical Results between Laser in situ Keratomileusis and Surface Ablation for Moderate to High Myopia

PURPOSE: To compare the long-term prognosis of laser in situ keratomileusis (LASIK) and surface ablation in moderate to high myopia. METHODS: A retrospective study including 87 eyes of 44 myopic patients treated with LASIK or surface ablation from 1995 to 2005 was performed. Follow-up visits were performed at 3 months, 1 year, 5 years, and 8 years. All treated eyes were divided into 2 groups according to preoperative spherical equivalent (SE)- moderate myopia (<-6.0 diopters [D]) and high myopia (≥-6.0 D). The main outcome measures were postoperative uncorrected visual acuity (UCVA), best corrected visual acuity, SE, mean keratometry, safety index, efficacy index, predictability, and complications. RESULTS: Mean SE was -7.05 ± 2.49 D in the LASIK group and -5.25 ± 1.23 D in the surface ablation group. The 10-year SE was -1.78 ± 1.22 D in the LASIK group and -1.35 ± 1.09 D in the surface ablation group, and there was no statistical difference between the 2 groups. At 10 years postoperatively, UCVA was log MAR 0.155 ± 0.161 in the LASIK group and log MAR 0.095 ± 0.140 in the surface ablation group. There were no significant differences in postoperative mean SE, safety index, efficacy index, or complications between the LASIK and surface ablation group at 10 years. CONCLUSIONS: This 10-year follow-up study shows that LASIK and surface ablation for moderate to high myopia have no statistical differences in mean SE, safety index, efficacy index, or complications.

Corneal sensitivity and dry eye after LASIK / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: Firstly to evaluate the changes of corneal sensation and its effect to dry eye syndrome after laser in situ keratomileusis (LASIK); secondly to evaluate the relation between the changes of corneal sensation and the laser ablation depth. ·METHODS: 30 patients (60 eyes) had bilateral LASIK with a superior-hinged flap. Every patient underwent preoperative and postoperative (after one week, one month and three months) evaluations, including corneal sensation, Schirmer's basic tear secretion test, tear breakup time (TBUT), corneal fluorescein stainting, and a questionnaire evaluating dry eye obtained from each patient.·RESULTS: Compared with preoperative level, after one week and one month, the difference of corneal sensation was very significant (P＜ 0.01); after three months, there was no statistical difference (P ＞ 0.05). After one week, there was no statistical difference (P ＞ 0.05) in the subjective dry eye symptoms, after one month, the difference was significant(P=0.025 ＜0.05) and after three months, the difference was very significant (P=0.001 ＜ 0.01). Compared with preoperative level, the basic tear secretion decreased significantly after one week and one month(P＜ 0.01), it did not return to the baseline level after three months (P ＜ 0.01). Tear breakup time decreased significantly after the surgery, and after three months, there was still statistical difference compared with preoperative level (P ＜ 0.01); with cornea fluorescence staining, we found corneal epithelial defect was most serious after one month after LASIK, and did not return to the baseline level after three months (P ＜ 0.01). Linear regression analysis and relevant were used to evaluate the relation between the changes of corneal sensation and the laser ablation depth (r=0.798, P ＜ 0.01). ·CONCLUSION: The central corneal sesation decreased noticeable after LASIK, and it recovered three months postoperatively, but the indicators of dry eye syndrome did not return to their preoperative levels following it. We have found that the decreasation of corneal sensation had positive correlation with the laser ablation depth.

Delayed onset diffuse lamellar keratitis following laser in situ keratomileusis / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To report a case of late onset diffuse lamellar keratitis (DLK) after laser in situ keratomileusis(LASIK) in 11 months due to corneal trauma. ·METHODS: A 22-year-old female patient underwent uneventful bilateral LASIK using a laserSight SLX excimer laser and Moria II microkeratome. No complications were observed during the operation and the early postoperative period.·RESULTS: 11 months after LASIK, grade I DLK was diagnosed after the book paper hurt the right corneal epithelium. The DLK responded rapidly to topical corticosteroid therapy, and healed in 2 weeks without complication. ·CONCLUSION: Although DLK Wpically develops in the early postoperative period, it could occur months after surgery. Treatment should begin as soon as DLK is diagnosed.

Retinal Function after Laser in Situ Keratomilensis / 中国康复理论与实践

@#ObjectiveTo observe the retinal function and nerve fiber layer (RNFL) thickness after laser in situ keratomileusis (LASIK). MethodsLASIK was performed in 15 cases (30 eyes) with myopia after strict preoperative examination. All examinations such as vision, correction vision, diopter, intraocular pressure, corneal thickness, ocular axis, topography scan and fundus of eye examination were performed before and 1 day, 1 week, 1 month,3 months and 6 months after operation, as well as electroretinography (ERG), visual evoked potential (VEP), optical coherece tomography at same time. ResultsThere was not significant difference in the intraocular pressure, ERG and VEP 1 day after LASIK. The thickness of RNFL decreased 1 week after LASIK (P<0.05) and recovered 1～6 months later. ConclusionLASIK does not disturb the retinal function and RNFL thickness irreversiblely.

Nerve Growth Factor Concentration and Implications in Photorefractive Keratectomy Versus Laser in Situ Keratomileusis

PURPOSE: To determine whether tear nerve growth factor (NGF) concentration correlates with corneal sensation and ocular surface dryness after photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK). METHODS: A prospective, non-randomized comparative clinical trial. Seventy eyes of 35 patients and 76 eyes of 38 patients underwent PRK and LASIK procedures to correct myopia and myopic astigmatism, respectively. Total tear protein level, tear NGF concentration, corneal sensation, tear film break-up time (BUT) and Schirmer values were measured before and 1 day, 1 week, 1 month, 3 months, and 6 months after the surgery. RESULTS: The postoperative mean tear NGF/total tear protein ratio (NGF/tP) increased in both PRK and LASIK patients compared to their preoperative levels (p<0.0001). At 1 week and 1 month postoperatively, the NGF/tP ratio was higher in PRK than in LASIK subjects (p<0.0001). Up to 6 months postoperatively, the mean corneal sensation after LASIK in the ablated zone was lower than the preoperative sensation (p<0.0001), whereas this was not the case in PRK subjects. Mean BUT and Schirmer values were significantly lower in LASIK-treated eyes compared to PRK-treated eyes up to 6 months postoperatively (p<0.0001). The early postoperative tear NGF/tP ratio correlated with the postoperative 6 month corneal sensation, BUT and Schirmer values. CONCLUSIONS: The difference in postoperative corneal sensation and ocular surface dryness between PRK- and LASIK-treated eyes was related to the difference in the early postoperative levels of NGF/tP, which implies NGF might influence corneal nerve regeneration after these two surgeries.

A Comparison of Corrective Effect on Astigmatism after LASIK and LASEK

PURPOSE: We studied the effect of LASIK and LASEK for correction of myopic astigmatism and the clinical results in relation to preoperative astigmatism and operative methods. METHODS: We retrospectively analyzed the results of 176 eyes of 97 patients in the LASIK group and of 56 eyes of 29 patients in the LASEK group. All patients had undergone LASIK or LASEK for correction of myopic astigmatism with MEL-70TM (Aesculap-Meditec, Jena, Germany). Patients were divided into groups I (or=3.00D) according to preoperative astigmatism, and into groups A (LASIK) and B (LASEK) according to operative method. Each patient was followed up for over 6 months with measurements of uncorrected visual acuity, manifested refraction, and spherical equivalent at 1, 3, and 6 months after operation. RESULTS: In groups IA, IB, IIA, IIB, IIIA, IIIB, IVA, and IVB, preoperative cylindrical errors were 0.56 +/- 0.17D, 0.61 +/- 0.13D, 1.27 +/- 0.28D, 1.24 +/- 0.21D, 2.18 +/- 0.25D, 2.10 +/- 0.25D, 3.39 +/- 0.66D, and 3.50 +/- 0.61D, and postoperative 6-month astigmatism measurements were 0.33 +/- 0.49D, 0.34 +/- 0.36D, 0.28 +/- 0.30D, 0.63 +/- 0.44D, 0.48 +/- 0.42D, 0.44 +/- 0.57D, 0.86 +/- 0.42D, and 1.00 +/- 0.78D, respectively. CONCLUSIONS: The correction of myopic astigmatism in LASEK was less effective than in LASIK at early postoperative periods, but they showed similar effect on the correction of astigmatism at 6 months after surgery, especially in the group with medium to low grade of astigmatism.

The Effect of PRK and LASIK for the Correction of Postkeratoplasty Astigmatism

PURPOSE: To evaluate the effect of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) procedure on eyes with high astigmatism after penetrating keratoplasty. METHODS: Thirteen eyes of 12 patients who had PRK (6 eyes) or LASIK (7 eyes) after penetrating keratoplasty were retrospectively reviewed. All patients had a stable postkeratoplasty astigmatism over 4.0D for a minimum of 6 months after all sutures were removed. We followed up patients in early phase (1~3 months) and late phase (6~12 months). RESULTS: Mean preoperative astigmatism in PRK patients was 7.96 +/- 2.63D and in LASIK patients 8.27 +/- 2.96D. Astigmatic magnitude decreased 54% in early phase, and 34% in late phase in PRK group. It decreased 58% in early phase, and 55% in late phase in LASIK group. The reduction of astigmatism and postoperative regression were not stastically significant between two groups. Postoperative uncorrected visual acuity improved 67% in PRK group and 86% in LASIK group above 2 Snellen chart lines. Postoperative corneal haze developed in 3 eyes of PRK group. CONCLUSIONS: PRK and LASIK resulted in improved uncorrected visual acuity and refraction in postkeratoplsty eyes with high astigmatism. But both procedures showed cylinderical undercorrection and postoperative regression in refraction. Mild corneal haze was common after PRK procedure.

Effect of Laser in Situ Keratomilieusis with Flying Spot Beam Laser on Astigmatic Correction

PURPOSE: The authors studied the results of laser in situ keratomileusis for correction of myopic astigmatism with flying spot beam laser. METHODS: The authors studied the results of 179 eyes of 122 patients who had undergone excimer laser in situ keratomileusis for correction of myopic astigmatism with flying spot beam laser and had had preoperative atigmatism greater than 0.5 diopter (D). Patients were divided into group I (0.50D-0.75D), II (1.00D-1.75D), III (2.00D-2.75D), and IV (3.00D-6.00D), Each patient were followed up for over 6 months. Refractive errors and uncorrected visual acuity (UCVA) were measured at 1week, 1, 3, and 6 months after operation, respectively RESULTS: The mean age of the patients was 29 years (19-50 years). In group I, II, III, and IV, preoperative cylindrical power were 0.61+/-0.12D, 1.26+/-0.24D, 2.26+/-0.28D, and 3.34+/-0.33D, respectively. And postoperative astigmatism were 0.11+/-0.25D, 0.16+/-0.31D, 0.63+/-0.55D, 0.45+/-0.67D at postoperative 3 month and 0.08+/-0.24D, 0.17+/-0.31D, 0.29+/-0.47D, 0.16+/-0.32D at postoperative 6month, respectively. At 6 months, there is no statistically significant difference compared with the mean cylindrical power between the two groups. CONCLUSIONS: The astigmatic correction with flying spot beam laser showed effective and stable results regardless of the preoperative cylindrical power.

Comparison of Wavefront Guided Customized Ablation vs. Conventional Ablation

PURPOSE: To compare the visual outcome and satisfaction rate after the wavefront guided ablation with the conventional ablation in laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK) patients. METHODS: We performed a prospective study that included 182 eyes of 91 patients who were treated with LASIK (60 eyes) or PRK (122 eyes) using MEL 70 excimer laser system (Carl-Zeiss Meditec, Germany). We applied wavefront guided ablation on the right eye of each patient. The conventional ablation (control group) was performed on the left eye of the same patient. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), spherical equivalent refraction, high order aberrations and contrast sensitivity were evaluated preoperatively and after surgery. Satisfaction rate was evaluated after surgery. RESULTS: We found statistically insignificant improvement of BCVA in wavefront guided ablation group. There were no statistically significant differences in contrast sensitivity between wavefront guided ablation and conventional ablation. In LASIK group, we found statistically significant differences of high order aberrations; RMS HO (High order)(p<0.05) and in PRK group; Z (3, -1), Z (3, 3), Z (4, 0), Z (4, 2), RMS HO (p<0.05). There were no statistically significant differences between wavefront guided ablation and conventional ablation in patient's satisfaction. CONCLUSIONS: High order aberrations of wavefront guided ablation were less increased than of conventional ablation. These results indicate the potential role of the wavefront guided ablation in the field of refractive surgery.

Corneal Flap Thickness according to Suction Time of Microkeratome in Porcine Eye

PURPOSE: The purpose of this study is to investigate the effect of the suction time in forming the corneal flap with microkeratome on the corneal flap thickness. METHODS: Thirty porcine eyes were randomly assigned into 3 groups according to suction duration: group 1(10 sec), group 2(35 sec) and group 3(60 sec). The Hansatome microkeratome with 160 plate and a suction ring with 8.5mm diameter were used to create corneal flap. The thickness of central cornea was measured with automated ultrasound pachymeter before the procedure. And after making the flap, the remained corneal thickness was measured with the same method. Then, the difference between the two values was thought to be the corneal flap thickness. RESULTS: The mean corneal flap thickness in group1, 2, and 3 were 91.0+/-24.1 micromiter, 110.1+/-8.9 mu m and 127.2+/-6.1 mu m, respectively. The difference was significant among the three groups(p=0.010), and the longer suction duration made the flap thicker. CONCLUSIONS: These results suggest that in forming the corneal flap with microkeratome, the suction duration has an effect on the corneal flap thickness and an increase of suction duration makes the flap thicker in porcine eyes.

A Case of Mycobacterium Fortuitum Keratitis at the Interface of the Cornea after LASIK

PURPOSE: To report a case of Mycobacterium fortuitum keratitis which occurred in the interface between the corneal stromal bed and flap after laser in situ keratomileusis (LASIK). RESULTS: Forty five year old female patient presented with clinical picture of keratitis 20 days after LASIK. The keratitis started with one soft round colony in the interface between the corneal stromal bed and the flap and, then progressed slowly with crystal shaped colonies. The keratitis worsened after removal of colonies showing partially method flap. Inflammation was controlled only after removal of the partially melted flap and with intensive medical treatment. Mycobacterium fortuitum keratitis was confirmed 2 months later by culture of the excised flap tissue. The patient's corrected visual acuity improved to 20/400 at 6 months after treatment. CONCLUSIONS: Mycobacterium fortuitum should be considered as one of the causes of keratitis manifesting white colonies after LASIK. The characteristics of the colonies may change during the course of the disease. Vigorous work-up should be considered for early identification of the organism.

Effectiveness of Intraepithelial Photorefractive Keratectomy (IE-PRK) for Myopic Regression after LASIK

PURPOSE: To evaluate the effectiveness of intreaepithelial photorefractive keratectomy (IE-PRK) for the treatment of myopic regression after laser in situ keratomileusis (LASIK) METHODS: 38 eyes of 22 patients who had previous LASIK for myopia were selected and retreated with IE-PRK, in which a photoablation was performed directly in the epithelium without damage to Bowman's layer. All eyes were elapsed at least 6 months after the LASIK. Follow-up was up to 6 months and within +/-0.50 of emmetropia on 6 months after surgery was considered as a success. RESULTS: Before IE-PRK, the eyes regressed to a mean of .1.26+/-0.45 D spherical equivalent (SE). The mean SE at 1 week after IE-PRK was .0.44+/-0.88 D, 1 month was .0.59+/-0.45 D, 3 month was .0.63+/-0.41, 6 month was .0.62+/-0.43 (p<0.05). 23 of the 38 eyes (60.5%) had refraction within +/-0.50 and were considered as successfully treated. Preoperative mean best corrected visual acuity (BCVA) was 0.33+/-0.18 (Snellen equivalent) and final mean BCVA was 0.77+/-0.99 (p<0.01). There were no significant complications of corneal flap. CONCLUSIONS: The results of this study indicate that intraepithelial photorefractive keratectomy appears to be a safe means for treating patients for regression after LASIK procedure. But success rate was not so good as the enhancement. Controlled studies with larger population will be necessary to evaluate the accuracy of the method more correctly.

Ocular deviation after unilateral laser in situ keratomileusis

Laser keratomileusis and excimer laser photorefractive keratectomy in situ are widely used therapies for treating myopia. The corrections of refractive error by glasses or contact lens result in a relatively equal refractive correction on both eyes. However, refractive surgery on a single eye can cause a focus disparity between both eyes and may result in the impairment of fusion leading to strabismus. This article aims to report a case where diplopia and esotropia occurred 1 month after laser keratomileusis (LASIK) in situ for the correction of myopia.

Clinical Result of 105 Cases Overcorrected Temporally after LASIK: 6 Months follow-up

This study aimed to evaluate the refractive and visual results of the cases temporally overcorrected after laser in situ keratomileusis (LASIK). Among 582 myopic eyes that underwent LASIK using VISX STAR from March 1997 to October 1998, 105 eyes were overcorrected more than one diopter (D) one week after LASIK. 105 eyes were divided into three groups according to their spherical equivalent (SE) at one week: Group l (> or = 3D, 9 eyes), group ll (2-2.9D, 14 eyes), and group lll (1-1.9D, 82 eyes).Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), SE, and complications were studied one day, one week, two months, and six months after LASIK. The mean preoperative SE was -11.17 +/-2.57D in group l,-9.40 +/-2.91D in group lland -8.09 +/-1.92D in group lll. At 6 months, the mean SE was 1.81 +/-1.61D, 0.04 +/-0.43D and -0.37 +/-0.76D in group l, ll and lll, respectively. The mean regression of SE from one day to six months was 1.85D, 2.27D and 1.73D in group l,ll and lll, respectively (p>0.05). The proportion of eyes that lost two or more lines of UCVA after LASIK compared to preoperative BCVA was 33.3% in group l, 10% in group ll, and 9.2% in group lll. There were central island (5 eyes), capsular wrinkling (3 eyes), free cap (1 eye), subepithelal metalic debris (1 eye), epithelial ingrowth (1 eye)as complications in all groups. With these results it might be concluded that hyperopia less than 3D one week after LASIK is temporary and disappears 6 months after surgery without any additional treatment, whereas hyperopia equal or more than 3D one week after LASIK still showed hyperopic refraction even after 6 months. Therefore, these eyes need further evaluation for the correction of hyperopia.

The Effects of Epikeratoplasty & Laser in Situ Keratomileusis(LASIK) for Correction of High Myopia

In order to compare the clinical results of Epikeratoplasty (EPK) with Laser in situ keratomileusis(LASIK) to be corrected of high myopia above -9 diopters, the effect of the procedure on 74 patients following EKP and 63 patients following LASIK who were followed up at least 1 year were analyzed retrospectively. Postoperative mean uncorrected visual acuity was reached 0.56 until 3 month in EKP group and 0.53 until 1 month in LASIK group. LASIK group recovered and stabilized more rapidly than EKP guoup(p<0.01). Also LASIK group had more rapid recovery in keratometryp(p<0.01) and mean refractive error than EKP group(p<0.01). But there was no significant difference between two groups in uncorrected visual acuity(p=0.62), keratometry(p=0.41) and mean refractive error(p=0.32) at postoperative 1 year. LASIK seems to have more rapid and effective visual recovery than EKP for high myopia treatment.

Femtosecond laser versus mechanical keratome in thin-flap laser in situ keratomileusis (LASIK) for correction of high myopia / 眼科

Objective To compare the safety,effectiveness and predictability of laser in situ keratomileusis (LASIK) with fem- tosecond laser (IntraLase) and mechanical microkeratome (Moria M2,head 90?m).Design Prospective clinical study.Participant 148 patients (274 eyes) with high myopia received operation of LASIK.Method The patients were assigned to receiving LASIK with corneal flap creation by Intralase femtosecond laser (134 eyes of 76 patients) or Moria 90 keratome (140 eyes of 72 patients),both groups receiving eximer laser ablation with VISX Star S4.Followed-up examinations such as visual acuity,refraction,wavefront aberra- tion,etc.were scheduled for 1 day,1 week,1 month and 3 months postoperatively.Main Outcome Measures Visual acuity,refrac- tion,wavefront aberration,Schirmer test and tear film breakup time(BUT).Results At 3 months after operation,108 eyes (80.6%) of IntraLase group had UCVA better than or equal to BSCVA preoperatively,showing no statistically significant difference to microker- atome group (116 eyes,82.9%,P=0.642).The mean residual spheroequivalent of refraction of IntraLase group was -0.49?0.70D,show- ing no statistically significant difference to microkeratome group (-0.56?0.83D,P=0.448).The mean Schirmer test of Intralase group was 9.5?4.0mm,showing no statistically significant difference to microkeratome group (9.5?7.2mm,P=0.950).The mean BUT of IntraLase group was 7.9?4.3s,showing no statistically significant difference to microkeratome group (8.08?5.48s,P=0.869).The postoperative higher-order aberrations of the IntraLase group was 0.480?0.133?m,lower than that of microkeratome group (0.578?0.169?m,P=0.034). Conclusions Thin-flap LASIK with femtosecond laser and mechanical keratome flap creation are both safe,effective for the correction of high myopia,showing good predictability and stability.Femtosecond laser has slightly better clinical outcomes than microkeratome.

Stress on recognition and perioperative management of dry eye after LASIK / 眼科

Dry eye is the most common complication after laser in situ keratomileusis(LASIK). Attention should focus on screening of dry eye before LASIK, decreasing risk factors of surgical manipulation and topical drugs effect on dry eye. Proper management before, during and after LASIK can minimize dry eye. (Ophthalmol CHN, 2006, 15:154-155 )