Visual Outcomes Of Dense Pediatric Cataract Surgery

[Background]Blindness and severe visual impairment are high priority public health issues in children,and cataract is a significant cause for child blindness worldwide.As a treatable cause of visual handicap in childhood,pediatric cataract is a priority of the"VISION 2020 Global Initiative".During the critical period of visual development,opaque lens lead to the development delay of macula by blocking the light.So patients with pediatric cataract should be operated on as soon as possible to maitain the residual visual function.The aim of the pediatric cataract surgery is to provide and maintain a clear visual axis and a focused retinal image.Lensectomy age is critical for the visual rehabilitation.With softer sclera and cornea,low immunity,and a relatively higher rate of reopacification of the visual axial,surgery could be difficult.Mean while.amblyopia,changing refractive error.strabismus.nystagmus that occurred after lensectomy are also unfavorable factors in visual rehabilitation of the children.Early and proper treatment of these problems can result in excellent vision in many cases.However,in many countries and some rural regions,the visual prognosis for these children is poor because of relatively late detection and diagnosis.poor medical conditions and poor compliance with long-term follow-up.In this study,we evaluated the visual outcomes of dense pediatric cataract surgery between January 2007 and December 2012 at Shandong Provincial Hospital affiliated to Shandong University.a large central medical center in eastern China.[Purpose]To evaluate the visual outcomes of dense pediatric cataract surgery.[Methods]Medical records of children who underwent surgery for dense unilateral or bilateral pediatric cataract in Shandong Provincial Hospital between January 2007 and December 2012 were collected.The inclusion criteria were as follows:(1)total cataract or axial opacities of the lens that were large enough to obscure the visual axis;(2)extracapsular lensectomy with/without anterior vitrectomy and with/without intraocular lens(IOL)implantation;(3)early postoperative optical correction for the aphakic eyes;(4)aggressive postoperative patching of the sound eye;(5)minimum postoperative follow-up of no less than 2 years.Risk factors for poor visual outcomes were analyzed.Routine preoperative examinations included assessment of best corrected visual acuity(BCVA)if possible.intraocular pressure(IOP)measurement.slit-lamp inspection,fundus examination and an A/B-ultrasonography scan.Young children who were uncooperative were examined under sedation with 10%chloral hydrate.Surgery was performed under general anesthesia as soon as the dense cataract was diagnosed.Extracapsular lensectomy with primary posterior capsulorhexis and anterior vitrectomy was performed.Posterior capsulorhexis and central anterior vitrectomy was preferred for patients younger than 6 years of age.Primary IOL implantation was performed in children over 2 years of age with bilateral cataract and in those over 1 year of age with unilateral cataract.After the surgery,topical antibiotics,corticosteroids,and cycloplegics were applied for several weeks.Amblyopia,refractive error should be treated vigorously and postoperative follow-ups should be completed on scadule.The following data were collected:sex、affected eyes、age at the time of surgery,seriously postoperative complications,development of strabismus and nystagmus,IOL status、periods of follow-up,and the final BCVA.The difference of the BCVA among lensectomy age groups,the difference of the BCVA between patients with bilateral cataract and that of patients with unilateral cataract in the same surgery age group,the difference of the BCVA among patients with primary/secondary/no IOL implantation,BCVA and its related risk factors were statistically analyzed.SPSS version 18.0 was used to perform the statistical analysis.The t-test,rank sum test,variance analysis and ordinal regression analysis were used to analyze the data.[Results]Of the 105 eligible patients(181 eyes),76 had bilateral cataract,and 29 unilateral.With a mean follow up of 46.77 mo(range 24.0～96.0 mo).The final BCVA of 158 eyes were recorded,and 4.43%(7/158)achieved 0.1 logarithm of the minimum angle of resolution(logMAR)or better;15.19%(24/158)obtained a BCVA between 0.1 logMAR and 0.3 logMAR;18.99%(30/158)between 0.3 IogMAR and 0.5 logMAR;46.84%(74/158)between 0.5 logMAR and I logMAR;14.55%,worse than 1 logMAR.The mean BCVA of the patients who underwent lensectomy before 3 months of age was significantly better than that of patients who underwent lensectomy between 3 and 12 months(P=0.001).In the same lensectomy age groups,the final BCVA of the children in the bilateral and unilateral groups did not differ significantly(P>0.05).Better visual outcomes were obtained in patients with primary IOL implantation than in those with secondary IOL implantation(P<0.01)or those with aphakic patients(P<0.01).The mean BCVA was better in patients with secondary IOL implantation than in aphakic patients(P = 0.015).Lensectomy after 3 months of age.postoperative complications,strabismus and nystagmus were shown to be risk factors for poor visual outcomes.[Conclusions]Lensectomy before 3 months of age,IOL implantation.proper managing of postoperative complications,early optical correction and aggressive postoperative patching of the sound eye would increase the final BCVA for patients with dense pediatric cataract.