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Background Aspheric intraocular lens (IOL) is designed to reduce the spherical aberration of the eye after cataract surgery and to obtain better visual quality.However,the selection of a personalized aspheric IOL is a problem to be solved.Objective This study was to compare the wavefront aberration and quality of vision of patients between the implantation of negative spherical aberration IOL and non-aberration IOL,and to investigate the relationship between corneal Q values and postoperative spherical aberration.Methods One hundred and four eyes of 90 patients with age-related cataract were randomized into two groups.Fifty-two eyes of 46 patients who received a Tecnis Z9001 IOL implantation were assigned as the negative spherical aberration IOL group and 52 eyes of 44 patients who received Akreos AO IOL without aberration were assigned as the non-aberration IOL group.The preoperative corneal Q values were measured and the mean Q value(Q)was computed.Then the patients in the two groups were further divided into 2 subgroups,respectively,based on their Q values were over or below (Q）.The corneal Q values,root mean square(RMS) of ocular spherical aberration,coma and total higher-order aberrations(HOAs) for 5 mm diameter pupil,scotopic contrast sensitivity with or without glare at 6 mm pupil diameter were measured 3 months after surgery.Results The pre-and post-operative corneal Q values were insignificantly changed (t =1.447,P =0.151).The spherical aberration in the negative spherical aberration IOL group was(0.059-±0.047)μm,and that in the non-aberration IOL group was(0.110±0.066)μm,with a statistically significant difference between them (t =-4.567,P=0.000).Scotopic contrast sensitivities at intermediate and high frequencies were significantly better in the negative spherical aberration IOL group than in the non-aberration IOL group (t =2.495,t =2.359,P ＜ 0.05).There was no significant difference in coma and HOAs between the two groups after operation (P ＞ 0.05).Weak positive correlations were seen between the pre-and post-operative corneal Q values and spherical aberration in the two groups(r=0.277,0.292,0.285,0.325,all at P＜0.05).However,no significant differences were found in spherical aberration,contrast sensitivity and scotopic contrast sensitivity between the different subgroups (P ＞ 0.05).Conclusions Negative spherical aberration IOL has lower spherical aberration and better scotopic contrast sensitivity than non-aberration IOL.The results suggest that it may be not enough to choose the corneal Q value only as the single reference criterion for selection of aspheric IOL.
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Background Heat shock proteins (HSPs) are highly conserved proteins that are induced in cells when confronted with a wide variety of proteotoxic stresses.HSP27 has a high degree of similarity with α-crystallin protein.The abnormality of HSP27 structure and expression are closely related to the formation of cataracts.Our previous study showed sodium salieylate has the protective effect on H2O2-induced lens damage.Objective This study was to investigate the roles of MAPK signal pathway in sodium salicylate-induced the expression of HSP27 in human lens epithelial cells (LECs) in vitro.Methods Human LECs were incubated in the fresh media containing sodium salicylate at different concentrations (0-55 mmol/L) for different times (1-5 hours) and allowed to be recovered in fresh medium without sodium salicylate for 1-24 hours with or without pretreatment with P38MAPK inhibitor (SB203580), ERK1/2 inhibitor (PD98059) and JNK/SAPK inhibitor ( SP600125). The expressions of P38MAPK, EBK1/2, JNK/SAPK, phosphorylated P38MAPK, phosphorylated ERK1/2, phosphorylated JNK/SAPK and HSP27 were detected by Western blot. HSP27 mRNA was detected by RT-PCR. The expression of HSP27 was also detected by immunohistochemistry. Results There was only weak expression of HSP27 in normal human LECs.After stimulation of 35-55 mmol/L sodium salicylate was removed and human LECs were cultured again for 6 hours,the expression of HSP27 in LECs were significantly increased ( F= 509. 953,P<0. 01). HSP27 was absent expressed in human LECs in 55 mmol/L sodium salicylate stimulation for 1-5 hours groups, but LECs were re-cultured for 3,6 hours after removed the stimulation, the expression of HSP27 was elevated (F = 452. 534, P<0. 01). Activation of P38 M APK occurred after sodium salicylate stimulation 30 minutes and 1 hour ( F = 865.68, P<0. 01). However, ERK 1/2 was expressed after sodium salicylate was eliminated for 1-6 hours ( F = 388.84, P<0. 01). JNK/SAPK was inactived by sodium salicylate. The expression of HSP27 could be down-regulated with the pretreatment of SB203580 and PD98059. Conclusion Sodium salicylatc can induce the expression of HSP27 in human (LECs) . The effects are mediated,at least in part ,through the activation of P38MAPK and ERK1/2 signaling pathway .
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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.
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AIM: To compare the visual effects of optimized aspheric transition zone Laser in situ keratomileusis (OAT z-LASIK )versus conventional Laser in situ keratomileusis (con. LASIK).METHODS: In a prospective study 44 patients (88 eyes)underwent OAT z -LASIK and 50 patients (92 eyes) received conventional LASIK surgery. Visual acuity,refractions、contrast sensitivity (CS),glare sensitivity (GS), and increment of Q-value after surgery were studied.RESULTS: All of operations on 94 cases were successful without severe complication after 3 months' follow-up. There was no significant difference in term of postoperative refractions between the two groups (t-test,P＞0.05). The uncorrected visual acuity (UCVA), CS, GS, and increment of Q-value of OAT z group were significantly better compared to the tradition group 3 months after the surgery (P＜0.05).CONCLUSION: OAT z - LASIK is a more effective procedure to improve visual quality compared to conventional LASIK.
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Objective To observe the outcome of patients with ocular cicatricial pemphigoid (OCP) after amniotic membrane grafting or penetrating keratoplasty.Design Retrospective,noncomparative case series.Participants 3 consecutive OCP patients (4 eyes),were included.Methods For 3 patients (4 eyes) in this study,preoperative visual acuity was from HM/5 cm to HM/10 cm.The symblepharon (gradeⅢ) of 2 patients (3 eyes) were detached and amniotic membrane was transplanted,and bandage contact lens were used till 2 months after operations.The other patient (1 eye) was undergone penetrating keratoplasty with glycerol-cryopreserved cornea because of corneal ulcer and perforation.Main Outcome Measures Visual acuity,recovering of conjunctiva and cornea.Results Am- niotic membrane dissolved about 1 month after operation in 2 patients (3 eyes).Symblepharon changed from gradeⅢto gradeⅡ,visual acuity increased to 0.04-0.05,central corneal epithelium was regenerated significantly,and a little new vessel appeared at corneal lim- bus in 2 patients (2 eyes).The graft deliquesced in the patient with penetrating keratoplasty at 20 days after operation and undergone penetrating keratoplasty again after 1 month.In this patient,the graft molten induced the ocular contents run-off and became eyeball at- rophy eventually.Conclusion Our small sample study shows that the symblepharon detachment and amniotic membrane transplantation is effective for improving visual acuity in OCP with ocular surface dysfunction.However,because of various factors,penetrating kerato- plasty is ineffective for OCP with perforating corneal ulcer.