Posters
Study on relevant factors of predictability to different refraction after SMILE surgery
Poster Details
First Author: Z.Fengju CHINA
Co Author(s): W. Dan
Abstract Details
Purpose:
To investigate the relevant factors of predictability to different refractive eyes before and after small incision lenticule extraction (SMILE) by analyzing the change of visual acuity��refraction and corneal epithelial thicknesses(ET) at different time following-up in order to guide reasonable preoperative design and postoperative care , and increase the predictable accuracy of SMILE and long- term satisfaction.
Setting:
Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital MedicalUniversity, Beijing Ophthalmology &Visual Sciences Key Lab, Beijing, China
Methods:
Retrospective observational study. 46 patients (90 eyes) with myopia were performed SMILE surgeries. The spherical equivalent (SE)of pre-op was -6.16�Â�±1.71D (-3.37�ï�½�-10.10D). and they were divided into three groups based on refractions�ï�¼� group A (44 eyes)was -3.00~-6.00D�ï�¼�group B (29 eyes) was -6.00~-8.00 D and group C(17eyes)was above -8.00. Uncorrected visual acuity (UCVA )�ï�¼�best corrected visual acuity (BCVA),manifest refraction, corneal thickness and epithelium thickness(ET) by spectral-domain optical coherence tomography (SD-OCT) were measured 7 days ,1 month and 3 months postoperatively�ï�¼�The results were analyzed with analysis of variance ,rank sun test and linear regression analysis�ï�¼�
Results:
1. The actual corneal ablation depth was smaller than theoretical output(P<0.001). The difference in group A was 9.8�Â�±5.2�Â�µm (a /t 90.0%); B was 11.1�Â�±6.8�Â�µm (a/t 90.8%); C was 15.1�Â�±7.2�Â�µm (a/t 86.8%), which was directly proportional to pre-op refraction (�ï�½�=0.521�ï�¼�P<0.001). 2. The increment of ET in group A is smaller than that of in B and C at 1m post-op(P<0.001) compared with pre-op. 3. At 3m follow-up, 49�ï�¼�
eyes in UCVA were equal to BCVA pre-op; 40���
eyes gained 1line BCVA; 10���
gained 2 lines and 1 eye dropped 1 line.
Conclusions:
The SMILE predictability has positive relations with the preoperative refraction and postoperative corneal epithelial hyperplasia. The difference between actual ablation depth and theoretical cutting output was directly proportional to the preoperative refraction . The SMILE procedure is safe, effective, predictable and stable for myopia.
Financial Disclosure:
NONE