AIM: To examine differences in efficacy, accuracy, safety, aberrations and corneal biomechanical between Small incision lenticule extraction (SMILE) and femtosecond lenticule extraction (FLEx) for myopia. METH...AIM: To examine differences in efficacy, accuracy, safety, aberrations and corneal biomechanical between Small incision lenticule extraction (SMILE) and femtosecond lenticule extraction (FLEx) for myopia. METHODS: Comprehensive studies were conducted on the PubMed, MEDLINE, EMBASE, and Cochrane Controlled Trials Register before 31 July, 2015. Meta-analyses were performed on the primary outcomes [loss of ≥2 lines of corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA) ≥20/20, spherical equivalent (SE) within ±0.50 diopters (D), final refractive SE], secondary outcomes were high-order aberrations (HOAs) and corneal biomechanical [central corneal thickness (CCT), corneal hysteresis (CH) and corneal resistance factor (CRF)]. RESULTS: Seven trials describing a total of 320 eyes with myopia were included in this Meta-analysis. No significant differences were found in the efficacy [UDVA weighted mean difference (WMD) -0.01; 95%CI: -0.04 to 0.01; P=0.37, UDVA ≥20/20, OR 1.49; 95%CI: 0.78 to 2.86; P=0.23], accuracy (SE WMD -0.03; 95%CI: -0.12 to 0.07; P=0.58 , SE within ±0.5 D OR 1.25; 95%CI: 0.34 to 4.65; P=0.74), HOAs (WMD -0.04; 95%CI: -0.09 to 0.01; P=0.14) and CCT WMD 1.83; 95%CI: -7.07 to 10.72; P=0.69, CH WMD -0.01; 95%CI: -0.42 to 0.40; P=0.97, CRF WMD 0.17; 95%CI: -0.33 to 0.67; P=0.50) in the last fellow-up. But for safety, FLEx may achieve fewer CDVA lost two or more two lines (OR 11.11; 95%CI: 1.27 to 96.86; P=0.03) than SMILE, however CDVA (WMD 0.00; 95%CI: -0.03 to 0.02; P=0.77) is similar. CONCLUSION: SMILE and FLEx are comparable in terms of both efficacy, accuracy, aberrations and corneal biomechanical measures in the follow-up,but FLEx seems to be better in safety measures. The results should be interpreted cautiously since relevant evidence is still limited, although it is accumulating. Further large-scale, well-designed randomized controlled trials are urgently needed.展开更多
AIM: To investigate cap morphology after small-incision lenticule extraction (SMILE) and its effects on intraocular scattering. METHODS: Sixty-five eyes of 33 patients undergoing SMILE were enrolled. In addition ...AIM: To investigate cap morphology after small-incision lenticule extraction (SMILE) and its effects on intraocular scattering. METHODS: Sixty-five eyes of 33 patients undergoing SMILE were enrolled. In addition to regular evaluation, Fourier-domain optical coherence tomography was used to investigate cap thickness at ld, lwk, 1 and 3mo postoperatively. The optical quality including modulation transfer function cutoff frequency, Strehl ratio, Optical Quality Analysis System (OQAS) values, and objective scattering index (OSI), were evaluated using OQASTM. RESULTS: Cap thickness decreased from ld to lwk (P〈0.001), but remained higher than intended thickness of 120 μm after 3mo (P〈0.001). Cap thickness in central area was thinner than that of in the paracentral and peripheral areas (P〈0.0001). Total number of microdistortions decreased from ld to 3mo (P〈0.0001). Pearson analysis revealed a weak correlation between OSI and standard deviation of cap thickness at ld and lmo, as well as between range of cap thickness and OSI at 1mo. No correlation was found between microdistortion and OSI, but a negative correlation existed between microdistortion and range at ld and lmoafter surgery. CONCLUSION: The corneal cap tends to be more accurate and regular with time lapse. Better cap morphology tends to contribute less intraocular scattering in the eyes undergoing SMILE.展开更多
BACKGROUND Diffuse lamellar keratitis(DLK)is a complication of laser-assisted in situ keratomileusis(LASIK).This condition can also develop after small-incision lenticule extraction(SMILE)with a distinctive appearance...BACKGROUND Diffuse lamellar keratitis(DLK)is a complication of laser-assisted in situ keratomileusis(LASIK).This condition can also develop after small-incision lenticule extraction(SMILE)with a distinctive appearance.We report the case involving a female patient with delayed onset DLK accompanied by immunoglobulin A(IgA)nephropathy.CASE SUMMARY A 22-year-old woman was referred to our department for DLK and a decline in vision 1 mo after undergoing SMILE.The initial examination showed grade 2 DLK in the flap involving the central visual axis of the right eye.She was immediately administered with a large dose of a topical steroid for 30 d.However,the treatment was ineffective.Her vision deteriorated from 10/20 to 6/20,and DLK gradually worsened from grade 2 to 4.Eventually,interface washout was performed,after which her vision improved.DLK completely disappeared 2 mo after washout.Six months after SMILE,the patient was diagnosed with IgA nephropathy due to a 4-year history of interstitial hematuria.CONCLUSION DLK is a typical complication of LASIK but can also develop after SMILE.Topical steroid therapy was ineffective in our patient,and interface washout was required.IgA nephropathy could be one of the factors contributing to the development of delayed DLK after SMILE.展开更多
Small Incision Lenticule Extraction(SMILE)is a flap-free intrastromal technique for the correction of myopia and myopic astigmatism.To date,this technique lacks automated centration and cyclotorsion control,so several...Small Incision Lenticule Extraction(SMILE)is a flap-free intrastromal technique for the correction of myopia and myopic astigmatism.To date,this technique lacks automated centration and cyclotorsion control,so several concerns have been raised regarding its capability to correct moderate or high levels of astigmatism.The objective of this paper is to review the reported SMILE outcomes for the correction of myopic astigmatism associated with a cylinder over 0.75 D,and its comparison with the outcomes reported with the excimer laser-based corneal refractive surgery techniques.A total of five studies clearly reporting SMILE astigmatic outcomes were identified.SMILE shows acceptable outcomes for the correction of myopic astigmatism,although a general agreement exists about the superiority of the excimer laser-based techniques for low to moderate levels of astigmatism.Manual correction of the static cyclotorsion should be adopted for any SMILE astigmatic correction over 0.75 D.展开更多
This review summarizes the current status of the small incision lenticule extraction(SMILE)procedure.Following the early work by Sekundo et al.and Shah et al.,SMILE has become increasingly popular.The accuracy of the ...This review summarizes the current status of the small incision lenticule extraction(SMILE)procedure.Following the early work by Sekundo et al.and Shah et al.,SMILE has become increasingly popular.The accuracy of the creation of the lenticule with the VisuMax femtosecond laser(Carl Zeiss Meditec)has been verified using very high-frequency(VHF)digital ultrasound and optical coherence tomography(OCT).Visual and refractive outcomes have been shown to be similar to those achieved with laser in situ keratomileusis(LASIK),notably in a large population reported by Hjortdal,Vestergaard et al.Safety in terms of the change in corrected distance visual acuity(CDVA)has also been shown to be similar to LASIK.It was expected that there would be less postoperative dry eye after SMILE compared to LASIK because the anterior stroma is disturbed only by the small incision,meaning that the anterior corneal nerves should be less affected.A number of studies have demonstrated a lower reduction and faster recovery of corneal sensation after SMILE than LASIK.Some studies have also used confocal microscopy to demonstrate a lower decrease in subbasal nerve fiber density after SMILE than LASIK.The potential biomechanical advantages of SMILE have been modeled by Reinstein et al.based on the non-linearity of tensile strength through the stroma.Studies have reported a similar change in Ocular Response Analyzer(Reichert)parameters after SMILE and LASIK,however,these have previously been shown to be unreliable as a representation of corneal biomechanics.Retreatment options after SMILE are discussed.Tissue addition applications of the SMILE procedure are also discussed including the potential for cryo-preservation of the lenticule for later reimplantation(Mohamed-Noriega,Angunawela,Lim et al.),and a new procedure referred to as endokeratophakia in which a myopic SMILE lenticule is implanted into a hyperopic patient(Pradhan et al.).Finally,studies reporting microdistortions in Bowman’s layer and corneal wound healing responses are also described.展开更多
基金Supported by the National Natural Science Foundation of China(No.81370993)
文摘AIM: To examine differences in efficacy, accuracy, safety, aberrations and corneal biomechanical between Small incision lenticule extraction (SMILE) and femtosecond lenticule extraction (FLEx) for myopia. METHODS: Comprehensive studies were conducted on the PubMed, MEDLINE, EMBASE, and Cochrane Controlled Trials Register before 31 July, 2015. Meta-analyses were performed on the primary outcomes [loss of ≥2 lines of corrected distance visual acuity (CDVA), uncorrected distance visual acuity (UDVA) ≥20/20, spherical equivalent (SE) within ±0.50 diopters (D), final refractive SE], secondary outcomes were high-order aberrations (HOAs) and corneal biomechanical [central corneal thickness (CCT), corneal hysteresis (CH) and corneal resistance factor (CRF)]. RESULTS: Seven trials describing a total of 320 eyes with myopia were included in this Meta-analysis. No significant differences were found in the efficacy [UDVA weighted mean difference (WMD) -0.01; 95%CI: -0.04 to 0.01; P=0.37, UDVA ≥20/20, OR 1.49; 95%CI: 0.78 to 2.86; P=0.23], accuracy (SE WMD -0.03; 95%CI: -0.12 to 0.07; P=0.58 , SE within ±0.5 D OR 1.25; 95%CI: 0.34 to 4.65; P=0.74), HOAs (WMD -0.04; 95%CI: -0.09 to 0.01; P=0.14) and CCT WMD 1.83; 95%CI: -7.07 to 10.72; P=0.69, CH WMD -0.01; 95%CI: -0.42 to 0.40; P=0.97, CRF WMD 0.17; 95%CI: -0.33 to 0.67; P=0.50) in the last fellow-up. But for safety, FLEx may achieve fewer CDVA lost two or more two lines (OR 11.11; 95%CI: 1.27 to 96.86; P=0.03) than SMILE, however CDVA (WMD 0.00; 95%CI: -0.03 to 0.02; P=0.77) is similar. CONCLUSION: SMILE and FLEx are comparable in terms of both efficacy, accuracy, aberrations and corneal biomechanical measures in the follow-up,but FLEx seems to be better in safety measures. The results should be interpreted cautiously since relevant evidence is still limited, although it is accumulating. Further large-scale, well-designed randomized controlled trials are urgently needed.
文摘AIM: To investigate cap morphology after small-incision lenticule extraction (SMILE) and its effects on intraocular scattering. METHODS: Sixty-five eyes of 33 patients undergoing SMILE were enrolled. In addition to regular evaluation, Fourier-domain optical coherence tomography was used to investigate cap thickness at ld, lwk, 1 and 3mo postoperatively. The optical quality including modulation transfer function cutoff frequency, Strehl ratio, Optical Quality Analysis System (OQAS) values, and objective scattering index (OSI), were evaluated using OQASTM. RESULTS: Cap thickness decreased from ld to lwk (P〈0.001), but remained higher than intended thickness of 120 μm after 3mo (P〈0.001). Cap thickness in central area was thinner than that of in the paracentral and peripheral areas (P〈0.0001). Total number of microdistortions decreased from ld to 3mo (P〈0.0001). Pearson analysis revealed a weak correlation between OSI and standard deviation of cap thickness at ld and lmo, as well as between range of cap thickness and OSI at 1mo. No correlation was found between microdistortion and OSI, but a negative correlation existed between microdistortion and range at ld and lmoafter surgery. CONCLUSION: The corneal cap tends to be more accurate and regular with time lapse. Better cap morphology tends to contribute less intraocular scattering in the eyes undergoing SMILE.
基金Supported by National Natural Science Foundation of China,No.81660169The Education Teaching Reform Project of First Clinical Department of Zunyi Medical College,No.202009.
文摘BACKGROUND Diffuse lamellar keratitis(DLK)is a complication of laser-assisted in situ keratomileusis(LASIK).This condition can also develop after small-incision lenticule extraction(SMILE)with a distinctive appearance.We report the case involving a female patient with delayed onset DLK accompanied by immunoglobulin A(IgA)nephropathy.CASE SUMMARY A 22-year-old woman was referred to our department for DLK and a decline in vision 1 mo after undergoing SMILE.The initial examination showed grade 2 DLK in the flap involving the central visual axis of the right eye.She was immediately administered with a large dose of a topical steroid for 30 d.However,the treatment was ineffective.Her vision deteriorated from 10/20 to 6/20,and DLK gradually worsened from grade 2 to 4.Eventually,interface washout was performed,after which her vision improved.DLK completely disappeared 2 mo after washout.Six months after SMILE,the patient was diagnosed with IgA nephropathy due to a 4-year history of interstitial hematuria.CONCLUSION DLK is a typical complication of LASIK but can also develop after SMILE.Topical steroid therapy was ineffective in our patient,and interface washout was required.IgA nephropathy could be one of the factors contributing to the development of delayed DLK after SMILE.
文摘Small Incision Lenticule Extraction(SMILE)is a flap-free intrastromal technique for the correction of myopia and myopic astigmatism.To date,this technique lacks automated centration and cyclotorsion control,so several concerns have been raised regarding its capability to correct moderate or high levels of astigmatism.The objective of this paper is to review the reported SMILE outcomes for the correction of myopic astigmatism associated with a cylinder over 0.75 D,and its comparison with the outcomes reported with the excimer laser-based corneal refractive surgery techniques.A total of five studies clearly reporting SMILE astigmatic outcomes were identified.SMILE shows acceptable outcomes for the correction of myopic astigmatism,although a general agreement exists about the superiority of the excimer laser-based techniques for low to moderate levels of astigmatism.Manual correction of the static cyclotorsion should be adopted for any SMILE astigmatic correction over 0.75 D.
文摘This review summarizes the current status of the small incision lenticule extraction(SMILE)procedure.Following the early work by Sekundo et al.and Shah et al.,SMILE has become increasingly popular.The accuracy of the creation of the lenticule with the VisuMax femtosecond laser(Carl Zeiss Meditec)has been verified using very high-frequency(VHF)digital ultrasound and optical coherence tomography(OCT).Visual and refractive outcomes have been shown to be similar to those achieved with laser in situ keratomileusis(LASIK),notably in a large population reported by Hjortdal,Vestergaard et al.Safety in terms of the change in corrected distance visual acuity(CDVA)has also been shown to be similar to LASIK.It was expected that there would be less postoperative dry eye after SMILE compared to LASIK because the anterior stroma is disturbed only by the small incision,meaning that the anterior corneal nerves should be less affected.A number of studies have demonstrated a lower reduction and faster recovery of corneal sensation after SMILE than LASIK.Some studies have also used confocal microscopy to demonstrate a lower decrease in subbasal nerve fiber density after SMILE than LASIK.The potential biomechanical advantages of SMILE have been modeled by Reinstein et al.based on the non-linearity of tensile strength through the stroma.Studies have reported a similar change in Ocular Response Analyzer(Reichert)parameters after SMILE and LASIK,however,these have previously been shown to be unreliable as a representation of corneal biomechanics.Retreatment options after SMILE are discussed.Tissue addition applications of the SMILE procedure are also discussed including the potential for cryo-preservation of the lenticule for later reimplantation(Mohamed-Noriega,Angunawela,Lim et al.),and a new procedure referred to as endokeratophakia in which a myopic SMILE lenticule is implanted into a hyperopic patient(Pradhan et al.).Finally,studies reporting microdistortions in Bowman’s layer and corneal wound healing responses are also described.