With the development of information society,asthenopia has more and more influence on social production and life.It has muhiple symptoms and complex causes.Its diagnosis is often ignored,because its clinical symptoms are often similar or related to other diseases.Simply and generally symptomatic treatment and neglecting to look for the causes and correct them is the present situation,We must strengthen the research of the diagnosis and treatment of asthenopia from a comprehensive perspective.We should establish standards and improve the skills of optometry,strengthen investigations of epidemiology,etiology and drug therapy of asthenopia.

Objective To investigate the effect of asustained reading task under cold bright light on steady-state accommodation in youths.Methods It was a self control study.Eighteen children with a mean age of 11.2±2.2 years performed a 40-minute reading task under 1000 Ix and 6500 K lighting conditions.The steady-state accommodative stimulus response curve (ASRC) and aecommodalive error were measured before and after the reading task.Near work-induced transient myopia (NITM) was measured immediately after the reading task followed by ASRC measurement.Results The mean ratio of accommodative error/accommodative stimulus was reduced after the reading task (P＜0.05).The magnitude of NITM was 0.29±0.24 D.The time decay imdex was 11.23±1838.The gradient and slope of ASRC and accommodative response did not change significantty after reading task.Conclusion Prolonged near work under cold bright light tends to improve accommodative accuracy and produce moderate near work-induced transient myopia.School children can use cold bright light while reading.

Objective To study the effect of pictorial and disparity depth cues on accommodative response,to analyze the effect of cue conflict on accommodative variability and response in the human visual system.Methods Experimental study.Thirty young adults with normal stereoscopic function participated in this study.Accommodative responses were continuously measured with a Grand Seiko WAM-5500 infrared auto-refractor under binocular viewing conditions.The targets were presented at a viewing distance of 50 cm on a stereoscopic display that included different depth cues:①no cue,②pictorial depth cue only,③disparity depth cue only,④disparity±pictorial depth cue Data were analyzed using a repeated measures analysis of variance.Results The accommodative responses to the 4 targets were 1.35±0.24 D,1.42±0.27 D,1.40±0.27 D and1.36±0.25 D,There were statistical different responses to the 4 targets (P＜0.05).In the same viewing environment,a strmulus with either a pictorial depth cue only elicited a higher accommodative response than a stimulus with no cue (P＜0.05),disparity depth cue only made higher accommodative response than with nothing cue stimulus (P＜0.05).However,there was no significant difference (P＞0.05) between the accommodative response to the disparity+pictorial depth cues stimulus and a stimulus with no cue.Conclusion Both disparity depth cue and pictorial depth cues increase accommodation,however,the effect of the summation of two depth cues on accommodative response is not a simple combined effect but a complex one.Compared with two-dimensional pictures,accommodative microfluctuations are steadier while viewing stereoscopic pictures using multiple cues in a short time interval.This may be related to focusing attention and positive adaptation using colorful 3D pictures in a short time interval.

Objective Compare the effectiveness of three treatment methods,namely the “convergence and accommodation training",the “correction of weared prism" and the “overcorrection of Myopic refractive" in patients with convergence insufficient exophoria accompanying with accommodative insufficiency.Methods It was a cross-sectional study.Sixty patients between 10 and 35 years' old who are diagnosed with convergence insufficient exophoria accompanying with accommodative insufficiency were randomly divided into three groups with 20 cases in each group.Patients in group A were corrected by weared prism,patients in group B were trated by the overcorrection of Myopic refractive (-0.50 D spectacles correction),patients in group C were treaded by convergence and accommodation visual function raining.Their phoria and visual functions were reviewed after three months.Results There are significant differences among the function parameters of the three groups of patients after review their visuals in three months' time.The heterophoria diopter increased in group A patients (t＝12.65、P＜0.01).The range of near-distance positive relative convergence has reduced (t=12.65,P＜0.01),after a short reduce,the symptoms of the patients in this group have increased.The heterophoria diopter of the patients in Group B has increased (t=4.63,P＜0.01).The range of near-distance positive relative convergence has reduced (t=6.71,P＜0.01).The accommodative amplitude decreased (t=14.3,P＜0.01) and the symptoms got worse significantly.However,the heterophoria diopter has significantly reduced in patients of group C (t=-1 1.61,P＜0.01).Their range of near-distance positive relative convergence has significantly increased (t=-22.40,P＜0.01),the accommodative amplitude (t=-31.06,P＜0.01) has increased significantly as well.Thesymptoms were improved significantly.Conclusion After the treatment of the convergence and accommodation visual function raining,the symptoms of the patients diagnosed with convergence insufficient exophoriaaccompanying with accommodative insufficiency were improved significantly,their heterophoria dioptcr has reduced,and the range of near-distance positive relative convergence and the accommodative amplitude has increased.In summary,this treatment is a feasible and effective treatment.

Objective To observe the effects of lutein on asthenopia after laser in situ keratomileusis (LASIK).Methods It was a prospocttve case control study.A total of 70 patients who had undergone LASIK were divided into treatment and control groups romdomly.The treatment group was treated with lutein in addition to conventional postoperative medication.Visual acuity,refractive error (RE),amplitude of accommodation,accommodative lag,accommodative facility,positive and negative relative accommodation,contrast sensitivity (CS) and asthenopia scores were measured at I week,I month and 3 months after LASIK surgery.Data were analyzed using chi-~square test and independent sample t test.Results The asthenopia score for the treatment group was lower than the score for the control group at 1 week,1 month and 3 months after LASIK surgery.The difference was significant (t=2.77,2.17,9.09,P＜0.05).There were significant differences in amplitude of accommodation and accommodative lag between the two groups at 3 months after LASIK surgery (t=2.35,2.57,P＜0.05).The differences in positive and negative relative accommodation and accommodative facility were not significant.The CS with or without glare was higher in the treatment group than in the control group at spatial frequencies of 1.7,2.6,6.6 c/d at I month after surgery.The differences were significant (with glare,t=3.68,2.84,2.45; without glare,t=2.15,2.60,3.09,P＜0.05).At 3 months after IASIK.Ihere were significant differences between the two groups in CS (with glare) at spatial frequencies of 1.0,2.6,4.2,10.4 c/d (t=3.47,5.64,4.56,4.10,P＜0.05).Compared to the control group,the CS without glare for the treatment group was higher at every spatial frequency at 3 months after LASIK.The differences were significant (t=2.16,2.31,3.51,5.56,5.00,4.62,P＜0.05).Conclusion Lutein can relieve Ihe symptoms and signs of asthenopia safely and effectively after LASIK.Aud it also can improve the CS of patients.

Objective To observe the pathogenesis and therapy of asthenopia.Methods It was a prospective case series study.One hundred and three patients with asthenopia were included.The function of accommodation and fusion test including distance and near phoria,horizontal convergence and divergence,near point,accommodative convergence/accommodation ratio,amplitude of accommodation,accommodative facility,relative accommodation,accommodative response was examed,and the pathogenesis was analyzed.Therapies include correct ametropia,vision training,prism correction,pharmacologic treatment.The symptom of asthenopia before and after treatment was evaluated with a qucstionnaire,and compared with a paired t test.Results The sex ratio of the 103 patients with asthenopia was 1:1.5 (male:female)、There were 38 cases of ametropia (36.9％),26 cases of dry eye (25.2％),29 cases with convergence or divergence problems (28.2％),and 10 cases with accommodation problems (9.7％).The symptom of asthenopia score was 4.8±0.7 before treatment,after treatment,all cases showed improvement in asthenopic symptoms,and the symptom of asthenopia score was 2.0±0.6,compare with before treatment,the difference was significant (t=16.0,P＜0.01 ).Conclusion Most of the patients with asthenopia had identifiable pathologies or deficits.The pathogenic causes of asthenopia are ametropia,dry eye,accommodation abnormalities,and convergence or divergence abnormalities.The therapy for correction of ametropia is training,prism,medication,etc.

Objective To study variations in visual acuity at multiple contrast levels and discuss the inherent differences as well as related factors by measuring the subjective vision of myopic children.Methods This was a cross-sectional study.The corrected visual acuity of 76myopic children aged nine to fifteen years was measured at different contrast levels (100％,25％,10％,5％) with a multifunctional visual acuity tester.Myopia ranged from -1.12 to -6 D.LogMAR contrast visual acuity was recorded.The correlation of visual acuity with age,spherical equivalent refraction and astigmatism was analyzed.Results ①At contrast levels of 100％,25％,10％,5％,the average visual acuities of the myopic children were -1.007,0.067,0.303 and 0.558,respectively.LogMAR values gradually increased with a decline in contrast levels (F＝321,P＜0.01).Contrast visual acuity decreased linearly at low contrast intervals.②The children were divided into two groups based on their contrast visual scuties.Children with lower contrast visual acuity accounted for 30.3％.There were no statistical differences between the two groups when age,spherical equivalent refraction and astigmatism were compared.③here were no statistical differences in contrast visual acuity between the two groups when age,spherical equivalent refraction and astigmatism were compared.Conclusion Contrast visual acuity in myopic children decreased linearly at low contrast intervals and was not affected by age,low and moderate myopia or astigmatism.Individual differences may infer the susceptibility of myopic progression.

Objective To evaluate the asphericity of the anterior and posterior comeal surfaces in myopic eyes with different corneal diameters.Methods It was a cross-sectional study.One hundred and sixteen eyes of 116 myopic or myopic astigmatism patients were enrolled.The preo perative spherical refraction was -1.25～-10.75 D,and the cyclindrical refraction was 0.00～-3.50 D.The Q-value and spherical aberration of the anterior and posterior corneal surfaces for different corneal diameters (6,7,8,9 mm) were measured with a Pentacam.The correlations between Q-value and spherical aberration,corneal refraction and central corneal thickness were investigated usiug a Pearson correlation,and a linear regression was used to establish the regressione quation of Q-value and spherical abberration.Results The Q6 mm,Q7 mm,Q8 mm,Q9 mm of the anterior corneal surfaces of the 116 eyes were -0.24±0.09,-0.29±0.09,-0.33±0.09,-0.39±0.10,respectively; posterior corneal surfaces were -0.12±0.12,-0.21±0.11,-0.30±0.10,-0.38±0.10,respectively.The Q-values of the anterior corneal surfaces were more negative than the posterior corneal surfaces,the differences were significant except the 9 mm (t=-10.35,-6.68,-3.46,P＜0.01).Positive relationships were found between the Q-value of anterior and posterior corneal surfaces for 6-9 mm corneal diameters (r=0.30,0.37,0.40,0.42,P＜0.01).For a 6 mm corneal diameter,the regression equation of the anterior corneal surface was SA=0.663Q+0.415,and the posterior corneal surface was SA=0.159Q-0.177.Positive relationships were also found between the anterior Q-values and cyclinder refractions for 6-9 mm corneal diameters (r=0.28、0.27、0.25、0.22,P＜0.05).Negetive relationship were found between the posterior Q value and comeal thickness for 7-9 mm corneal diameter (r=-0.18,-0.21,-0.24,P＜0.05).ConcIusion Both the anterior and the posterior corneal surfaces in myopic eyes were prolate.As the corneal diameter increased,the Q-values became more negative.The relationship between Q-value and corneal spherical aberration can provide more valuable instructions for refractive surgeons when designing aspheric ablation.

Objective To investigate anterior segment variations under miotic and mydriasic conditions in patients with a posterior chamber implantabble collamer lens (ICL).Methods Ten patients (19 eyes) who underwent ICL implantation surgery at least two weeks prior were enrolled randomly in this self-controlled study.One percent pilocarpine or compound tropicamidc was administered to induce miosis or mydriasis,simulating responses to bright light or dark condifions.Parameters of the anterior segment under normal light conditions without eye drops,and with miosis and mydriasis were measured with anterier segment-optical coherence tomography,including anterior chamber depth (ACD),ICL vaulting and the white-to-white (WTW) distance.A paired t test was used to analyze the data.Results ACI) was 3.61±0.20 mm under normal conditions,3.42±0.15 mm under miosis and 3.64 ±0.22 mm under mydriasis.ACD in miosis was significantly shallower than under normal conditions (t=7.89,P＜0.01),while there was no difference between ACD in mydriasis and normal conditions.Vaulting was 0.61±0.14 mm under normal conditions,0.41±0.10 mm in miosis and 0.64±0.14 mm in mydriasis.Vaulting in miosis was significautly narrower than under normal conditions (t=10.51,P＜0.01),while there was no difference between vaulling in mydriasis and normal conditions.WTW distance was 11.40±0.28 mm under normal conditions,11.38±0.32 mm in miosis and 11.35±0.30 mm in mydriasis.There was no difference between WTW in miosis,mydriasis or normal conditions.Conclusion The anterior segment variations of patients with ICL under miosis or mydriasis stayed within a safe range.

Objective To evaluate the visual outcome of modified monocular prcsbyLASIK (laser in situ keratomileusis) for myopia,astigmatism and presbyopia using Custom-Q software.Methods It was a prospective case series study.Ten myopic patients with presbyopia,40 years or older,underwent monocular presbyLASIK from June 2009 to February 2010,whereby the dominant eyes were corrected for distance with conventional wavefront optimized LASIK and the non-dominant eyes were corrected for near vision with individually adjusted aspheric,Q-value guided ablations.The visual results were described at each postoperative visit (I week,1 month,3 months,6 months and 1 year).Questionnaires were used to characterize patient ocular conditions before surgery and satisfaction with improved monocular prosbyLASIK postoperatively.Analysis of variance,paired t test and Wilcoxon-rank sum test were used for data statistics.Results ①Both postoperative distance uncorrected visual acuity (UCVA) and near UCVA in the non-dominant eye and binocular vision were better after surgery,and the differences were significant (P＜0.01).②Stability:after surgery,the differences in postoperative distance UCVA and near UCVA in the binocular vision at the different time points were not significant.③Safety:the operations were successful and there were no complications.Postoperative best corrected visual acuity (BCVA) in the non-dominant eye did not decrease.④Satisfaction:the patient subjective satisfaction score was 8.40±0.88.The questionnaire indicated that preoperative and postoperative satisfaction with spectacle dependency differed (Z=-2.527.-2.609,P＜0.05).Conclusion This improved monocular presbyLASIK procedure using Custom-Q ablation may be a valuable option for presbyopic individuals considering refractive surgery.Visual results,safety,stability and satisfaction were excellent.

Objective This study aims to determine the changes in the biomechanical properties of the anterior and extreme posterior portions of experimentally induced myopic eyes by examining the mechanical behavior of guinea pig scleral desmocytes,thus finding a new approach to the pathogenesis of myopia and the corresponding therapies.Methods Experimental study.Guinea pigs (2 weeks old) were numbered and assigned into 3 groups (A,B,and C),each with 10 guinea pigs.Concave lens-induced myopic (LIM) animal models were prepared via the out-of-focus method.The other eye in the same guinea pig served as the self-control (SC) group.After modeling groups A,B,and C for 6,15,and 30 days,respectively,the lenses from the guiuea pigs in the experimental group were removed.The scleral fibroblasts in each group were cultured and passaged twice in vitro.The micropipette aspiration technique coupled with a viscoelastic solid model was utilized to investigate the viscoelastic properties of the scleral fibroblasts in normal and group at 30 days were significantly higher than those of the LIM group at 6 and 15 days,as well as those in the SC group (P＜0.05),The extreme posterior portions of the sclera in the LIM group at 6 days after myopic induction did not differ significantly from those of the SC group (P＜0.05).However,the extreme posterior portions of the sclera in the LIM group after 15 days and 30 days were significantly higher than those in the LIM group at 6 days and the SC group (P＜0.05).Conclusion Young's modulus and apparent viscosity of the anterior and extreme posterior portions of the sclera changed by the 15th and 30th days,respectively,after induction.

Objective To evaluate the changes in the distribution of peripapillary and macular retinal nerve fiber layer (RNFL) thickness distribution in a group of subjects with high myopia.Methods It was a prospective case control study.Thirty-three eyes of 33 patients with high myopia (33 eyes) and 35 eyes of 35 control subjects (35 eyes) were recruited in jinhua Municipal Central Hospital from March 2011 to August 2011.Macular RNFL thickness was measured in the macular fovea and 750 μm away from the center of the fovea in the superior,inferior,temporal and nasal directions using optical coherence tomograhy (OCT).Peripapillary RNFL thickness was measured using the OCT Fast RNFL 3.4 mr scan protocol.An independent samples t test was used to compare the difference between the two groups.Results The thickness of macular RNFL was significantly thinner in patients with high myopia than that in the control subjects.Although there was no significant difference in peripapillary RNFL thickness between the patients and the controls,tthere was a trend to be thinner in the patients with high myopia in each the 12 o'clock hour direction.Conclusion It is significant that the thickness of the macular RNFL is thinner in patients with high myopia than that in control subjects.Particular caution is needed to prevent false positive errors when the RNFL appears to be below the normal limit in glaucoma patients complicated by high myopia.OCT offers a good method to evaluate the thickness of RNFL and to be used in follow-ups.

Objective To analyze the formation of anterior chamber bubbles during corneal flap creation in myopic patients who underwent laser-in-situ keratomilusis (LASIK) using the lntraLase femtosecond laser.Methods It was a restrospective case control study.One thousand thirty-four patients (2057 eyes) who underwent LASIK using the IntraLase femtosccond laser were enrolled in this study.Anterior chamber gas bubbles were noted in study group (51 eyes) with no anterior chamber gas bubbles in the other 2007 eyes (control group).The causes of anterior chamber buble formation were analyzed.The date were analyzed by independent samples t test.Results Flap creation was successful and myopic ablation was uneventful.The conneal diameter in the study group was smaller than that in the control group (t=-9.21,P＜0.05),but there were no significant differences between the two groups in other corneal parameters.Conclusion With a larger pupil and precise tracking,anterior chamber bubbles has no effect on postoperative visual acuity.To avoid the formation of anterior chamber bubbles during corneal flap creation,we would tighten the flap diameter in smaller corneas.

Objective To determine the efficacy of converse ocular conjunctival flap transposition in the management of pterygium under the microscope.Methods It was a retrospective case series study.One hundred thirteen eyes of 87 patients with pterygium who were treated by surgical excision of pterygium and converse ocular conjunctival flap transposition under the microscope between March 2006 and March 2010 were retrospectively reviewed.The mean age was 66.0±9.8 years and the course of disease was 1-20 years.All patients who underwent surgery were followed up for 1-3 years.Patients were examined 1 week after surgery,including the transposed conjunctival flap,the healing of the donor site and corneal trauma.Recurrence of pterygia or eye movement disorder was noted.Results The most common and persistent complaints were hyperemia,edema,and foreign body sensation at the surgical site,which decreased over a 2-4 day period.At one week,all the conjunctival flaps healed.Seven eyes (6.2％) experienced a recurrence with a small fibrovascular band extending anterior to the corneal limbus 3-14 months after surgery.One hundred and six of 113(93.8％) eyes were free of recurrence.There were no major complications threatening visual acuity in the surgical patients.Conclusion Pterygium excision combined with ocular conjunctival flap appeared to be an effective surgical technique for preventing pterygium recurrence and this technique was a simple and safe alternative for pterygia.

Complicated and nonspecific clinical manifestations of asthenopia bring certain difficulties to clinical diagnosis and etiolo gical treatment of it.With the in-depth understanding of the disease,its etiology is very complex and often multifactorial.Therapeutic effect is not ideal if only symptomatic treatment was delivered.Exploring the causes of the disase and treating them is the basic therapeutic strategy.It has become clear that many factors can lead to asthenopia.Some necessary ophthalmologic and optometry examinations can ensure etiological diagnosis.Different etiological treatments for asthenopia are with different difficulties.Only simply removal or correction of some causes can avoid symptoms,while others are relatively difficult,such as accommodation and convergence.On the other hand,the poor popularity of the examination of accommodation and convergence makes it difficult to find their effect on asthenopia and to treat them.We summarized the status quo of the diagnosis and therapy of accommodative insufficiency and convergence insufficiency in asthenopia,in order to contribute to the clinical work.