هدف: مقايسه نتايج بينايي بين دو روش جراحي Wavefront Optimized((WFO و Topography-guided Customized Ablation (T-CAT) براي اصلاح نزديكبين آستيگماتيسم مركب. روش پژوهش: در اين كارآزمايي باليني آيندهنگر دوسوكور، 40 چشم (21 بيمار) نزديكبين آستيگماتيسم مركب وارد مطالعه شدند. عيب انكساري نزديكبيني، يك الي هشت ديوپتر و آستيگماتيسم، يك الي سه ديوپتر در نظر گرفته شد. چشمهاي بيماران به صورت مستقل و تصادفي در دو گروه WFO و T-CAT قرار گرفتند. كليه جراحيها با ليزر Allegretto WaveLight® EX500 صورت پذيرفت. حدت بينايي، رفركشن، ابيراهيهاي قرنيهاي و چشمي و آسفريسيته قرنيه در بيماران قبل و شش ماه پس از جراحي اندازهگيري شد و نتايج بين دو گروه مقايسه گرديد.
يافتهها: شش ماه پس از عمل جراحي، حدت بينايي با بهترين تصحيح بين دو گروه مشابه بود. ميانگين معادلكروي قبل از عمل 1/7±4/33- ديوپتر و 1/61±4/13- ديوپتر (0/528=P) و شش ماه بعد از عمل 0/14±0/06- ديوپتر و 0/09±0/04- ديوپتر (0/586=P) در گروههاي WFO و T-CAT بود. . در روش T-CAT، بافت استرومايي كمتري نسبت به WFO برداشته شد (P=0/969). تفاوت معنيداري بين ابيراهيهاي قرنيهاي رده سوم و چهارم زرنيكه بين دو گروه قبل و پس از عمل وجود نداشت (0/05
چكيده لاتين :
Purpose: To compare the visual outcome between wavefront-optimized (WFO) and topography-guided customized ablation (T-CAT) for compound myopic astigmatism.
Methods: This double blind, prospective clinical trial study comprised 40 eyes (21 patients) with compound myopic astigmatism. Myopia was considered between 1 to 8 diopters and astigmatism was considered between 1 to 3 diopters. Patients were randomly divided into two groups: 1) the wavefront optimized group and 2) the topography-guided group. All surgeries were done with Allegretto WaveLight® EX500laser eximer. Visual acuity, refractive error, corneal aberrations, ocular high order aberrations and corneal asphericity were measured before and 6 months after surgery. The results were compared between the two groups.
Results: Six months after surgery, the best corrected visual acuity was similar in two groups. Mean spherical equivalent refraction was -4.33 ± 1.7D and -4.13 ± 1.61 D (P=0.528) to -0.06 ± 0.14 D and -0.04 ± 0.09D (P=0.586) in wavefront optimized and topography-guided groups after surgery. Less stromal tissue was ablated in the topography-guided group than in the wavefront optimized group (P = 0.969). There was no significant difference between the 3rd and 4th grade corneal aberrations between the two groups before and after the surgery (P>0.05). Corneal spherical aberration was increased in both groups. This increase was higher in the WFO group (P = 0.798). Higher order aberrations increased from 0.35 ± 0.14 μm and 0.35 ± 0.11 μm (P=0.496) to 0.52 ± 0.15μm and 0.49 ± 0.16 μm (P=0.786) in the WFO and T-CAT groups, respectively. Corneal asphericity increased in group two, which was higher in the WFO group (P=0.679).
Conclusion: The results of topography-guided and wavefront optimized treatments with Allegretto eximer laser were similar in the correction of compound myopic astigmatism, but TCAT induced fewer HOAs.