The Clinical Observation About How The Pterygium Surgery Influence The Human Conea And The Calculation Of The Intraocular Len's Degree And The Relationship Among Them

Part I:The effect of the pterygium surgery to the corneal parameterObjection The study is focusing on the effect of the pterygium surgery to the corneal parameter.Method Choose 32 patients who have got pterygium surgery treatment in the second affiliated hospital of Guangzhou Medical university during July 2016 and March2017 with total 42 pterygium eyes cases as the “pterygium group”,and the 22 opposite normal eyes cases in the as the “contrast group”,collect the relevant data preoperative and postoperative 1 month,3 months.Select 30 cases without pterygium history and eye surgery history for total 60 eyes samples as “normal group”.Before the surgery,measured the length,width and area of pterygium in each case.Datas were measured Preoperative and postoperative 1 month,3 month which contains the best corrected visual acuity(BCVA),intraocular pressure(IOP),tear membrane breaking up time(BUT),corneal curvature(horizontal,vertical and average value),corneal astigmatism,corneal refractive power,central corneal thickness.Results1.It is the recommended dividing value that help to access whether the pterygium has influence the corneal curvature that 2.15 mm of the pterygium's length,3.30 mm of the width,3.48 mm2 of the pterygium's area.2.The BCVA,the BUT,the corneal refractive power and the corneal horizontal and average curvature improve,and the corneal astigmatism decrease postoperatively.There is no more improvement between postoperative 1 month and 3month.3.The IOP,central corneal thickness and the corneal vertical curvature of pterygium have no obvious change postoperatively.4.The preoperative corneal astigmatism is positively correlated with the size of the pterygium.The postoperative corneal astigmatism is positively correlated with the width of the pterygium.The change of corneal refractive power is positively correlated with the size of the pterygium.Conclusion1.The pterygium could cause the corneal astigmatism increase,the refractive power decrese and the corneal curvature more flatter.2.The pterygium surgery could decrease the corneal astigmatism and improve the corneal curvature.3.The influence of the pterygium surgery to the corneal parameter is positively correlated with the size of the pterygium.Part II:The effect of the pterygium surgery to the IOL power calculationObjection The study is focus on the effect of the pterygium surgery to the IOL power calculation.Method Choose 32 patients who have got pterygium surgery treatment in the second affiliated hospital of Guangzhou Medical university during July 2016 and March2017 with total 42 pterygium eyes cases as the “pterygium group”,and the 22 opposite normal eyes cases in the as the “contrast group”,collect the relevant data preoperative and postoperative 1 month,3 months.Before the surgery,measured the length,width and area of pterygium in each case.Datas were measured Preoperative and postoperative 1 month,3 month which contains the IOL power calculation,the corneal curvature(horizontal,vertical and average value),the eye axial length,the anterior chamber depth and the theoretic calculated degree of intraocular lens.Results1.When the pterygium is too large,it could cause the IOL power calculation improve,the corneal refractive power decrease and the corneal horizontal and average curvature more flatter.Operation of surgery could reverse,but no significant change postoperative 1 month and 3 month.2.The eye axial length and the anterior chamber depth have no obvious change postoperatively.3.It is the recommended value that help to access whether the pterygium has influence the IOL power calculation that 2.15 mm of the length,2.15 mm of the width,4,46 mm2 of the area.It is the recommended value that help to access whether the pterygium has obviously influence the IOL power calculation that 2.15 mm of the length,4.20 mm of the width,5.175 mm2 of the area.Conclusion1.The pterygium surgery affects the IOL power calculation through the effect of the corneal curvature.2.When the pterygium is too large,it may influence the IOL power calculation clinically.