Risk Factors Related To Early Visual Acuity And Changes Of Corneal Curvature After Cataract Surgery Among The High Myopia Patients

Chapter I: Factors Affecting Early Vision Recovery in High Myopia Cataract SurgeryObjective:To explore the influencing factors of early visual acuity after cataract surgery in high myopia and to provide a basis for better prediction of postoperative visual acuity and better postoperative efficacy.Methods : A retrospective analysis of 93 patients(115 eyes)with high myopia associated with cataract patients,one week after surgery to measure uncorrected visual acuity and check the fundus.The patients were divided into two groups according to postoperative corrected visual acuity,<0.3 for the low vision group,≥ 0.3 for the better vision group.Single factor and multivariate Logistic regression were used to analyze the relationship between age,sex,BMI,systolic blood pressure,diastolic blood pressure,axial length,anterior chamber depth,corneal curvature,cataract type,operation method,macular degeneration,posterior staphyloma,preoperative vision grade and early vision after high myopia cataract surgery.Results:1.There were significant differences in age,axial length,anterior chamber depth,preoperative visual acuity grade,macular degeneration,posterior staphyloma between low vision and normal vision group(P <0.05);2.The preoperative visual acuity(OR: 4.835,95% CI : 1.962-11.915),macular degeneration(OR: 5.586,95% CI: 1.704-18.311),posterior staphyloma(OR: 3.698,95% CI: 1.002-13.652)were related to early postoperative visual acuity(P <0.05),and these were independent influencing factors of early postoperative visual acuity.The lower the preoperative visual acuity level,with macular degeneration and posterior staphyloma,the worse the early postoperative visual acuity in patients with high myopia cataract.Conclusions:1.Compared with the normal vision group,the age of the low vision group was older,axial length was longer,anterior chamber depth was shallower,preoperative visual acuity was lower,and proportion of patients with maculopathy and posterior scleral staphyloma was higher;2.The lower the preoperative visual acuity,with macular degeneration and posterior staphyloma were risk factors for early postoperative visual acuity in patients with high myopia and cataract,including macular degeneration> preoperative visual acuity> posterior staphyloma.Chapter 2: Changes of Corneal Curvature Before and After High-myopia Cataract SurgeryObjective:To evaluate the changes of corneal curvature by corneal topography in patients with high myopia and normal cataract,analyze the changes of corneal anterior and posterior surface curvature between two kinds of surgical incision size,whether with high myopia or different postoperative visual acuity,and changes within the group.Methods:Retrospective analysis of 35 cases(40 eyes)was divided into groups A and B according to whether the cataract was accompanied by high myopia.Each group had 20 eyes;the size of the incision of 5.5 mm(cataract extraction with small incision)and 3.2mm(phacoemulsification)were divided into groups C and D,22 eyes in C group and 18 eyes in D group;according to the postoperative naked visual acuity <0.3 and ≥ 0.3 were divided into E,F group,E group 15 eyes,F group 25 eyes,recorded Patient’s age and gender,and other clinical datas.The anterior and posterior corneal surface curvature,central corneal thickness(CCT)and anterior chamber depth(ACD)were measured at 1 day before operation and 1-3 days after operation.The changes of corneal curvature and whether accompanied with high myopia,postoperative visual acuity,the relationship between surgical incision size and all the parameters of patients before and after surgery.Results:1.Compared with the normal group,the postoperative uncorrected visual acuity(P=0.000),postoperative front corneal surface 3 mm below the central corneal diameter range(hereinafter referred to the temporal below)of the high myopia group had statistical significances(P = 0.046);There was significant difference in posterior corneal astigmatism(P = 0.036)between the two different incision sizes;According to the postoperative visual acuity,postoperative corneal anterior surface astigmatism(P = 0.04)was different;2.Within group of cataract with high myopia,there were statistically significant changes in the posterior surface of above the nasal,anterior and posterior surface astigmatism(ie,surgically induced astigmatism)and the abrupt axis of the posterior surface;the parameters of nasal below in posterior corneal surface,and posterior surface astigmatism were statistically significant between preoperative and postoperative in the normal cataract group.Conclusions:1.The visual acuity of high myopia cataract patients was significantly lower than that of the normal cataract group 1 week after operation;2.postoperative curvature of front corneal surface temporal below was associated with high degree of myopia;postoperative corneal posterior astigmatism was corcerned about surgical incision size;postoperative corneal anterior surface astigmatism,preoperative corneal surface curvature of the nose above were related to postoperative visual acuity;3.High myopia group cataract surgery affected posterior surface of above the nasal,anterior and posterior surface astigmatism(ie,surgically induced astigmatism),steep axial axis of the posterior surface;normal group cataract surgery affected posterior nasal below,posterior surface astigmatism.