AIM:To evaluate the clinical outcomes after subsequent implantation of a new intrastromal corneal ring segment(ICRS)model followed by an additional short-arc ICRS implant in keratoconus patients.METHODS:This retrospec...AIM:To evaluate the clinical outcomes after subsequent implantation of a new intrastromal corneal ring segment(ICRS)model followed by an additional short-arc ICRS implant in keratoconus patients.METHODS:This retrospective single-arm cohort study evaluated 25 eyes of 21 keratoconus patients implanted with the new ICRS followed by 140-arch length ICRS(140-ICRS)implantation.Uncorrected distance visual acuity(UDVA,logMAR),corrected distance visual acuity(CDVA,logMAR),sphere,astigmatism,keratometry,spherical equivalent(SE),and asphericity were compared preoperatively and postoperatively after both ICRS implantation.RESULTS:The average follow-up time after 140-ICRS implantation was 6.40±2.20mo.The mean preoperative UDVA improved from 1.27±0.14 preoperative to 0.52±0.26 after both ICRS implantation(P=0.03).The mean sphere value reduced from-5.34±2.74 preoperatively to-2.06±1.84 postoperatively(P<0.001)after the first ICRS implantation and decreased to-0.59±1.54 postoperatively(P<0.001)after 140-ICRS implantation.The mean preoperative astigmatism was-3.72±1.56 and improved to-2.82±1.08 after the first ICRS implantation,and following the 140-ICRS implantation,the mean astigmatism was-1.37±0.67(P=0.001).The SE and asphericity changes were statistically significant(P<0.001).The researchers did not find intraoperative or postoperative complications for both procedures.CONCLUSION:The combination of 2 different ICRSs can efficiently regularize the cornea,reduce the SE,and improve visual acuity in selected keratoconus patients.展开更多
AIM:To evaluate corneal parameters measured with a dual Scheimpflug analyzer in keratoconus patients implanted with intrastromal corneal ring segments(ICRS).METHODS:Fifty eyes of 40 keratoconus patients had Ferrar...AIM:To evaluate corneal parameters measured with a dual Scheimpflug analyzer in keratoconus patients implanted with intrastromal corneal ring segments(ICRS).METHODS:Fifty eyes of 40 keratoconus patients had Ferrara ICRS implantation from November 2010 to April2014.Uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),refraction,keratometry,asphericity,elevation,pachymetry,root mean square(RMS),spherical aberration and coma were studied.All patients were evaluated using a dual Scheimpflug system.RESULTS:The mean follow-up time after the procedure was 12.7mo.The mean UCVA improved from0.82 to 0.31(P〈0.001);the mean BCVA improved from0.42 to 0.05(P〈0.0001),the mean spherical refraction changed from-3.06 ±3.80 D to-0.80 ±2.5 D(P〈0.0001)and the mean refraction astigmatism reduced from-4.51 ±2.08 D to-2.26±1.18 D(P〈0.0001).The changes from preoperative to postoperative,in parameters of the anterior and posterior surface of the cornea,were statistically significant except the elevation posterior at the apex of the cornea and posterior asphericity.CONCLUSION:The implantation of Ferrara ICRS induces changes in both anterior and posterior surfaces of the cornea.展开更多
AIM:To evaluate the clinical and tomographic outcomes after implantation of a new intrastromal corneal ring segment(ICRS) with 140-degrees of arc in eyes with corneal ectasia.METHODS:We evaluated patients with cor...AIM:To evaluate the clinical and tomographic outcomes after implantation of a new intrastromal corneal ring segment(ICRS) with 140-degrees of arc in eyes with corneal ectasia.METHODS:We evaluated patients with corneal ectasia implanted with Ferrara 140° ICRS from April 2010 to February 2015.Outcome measures included preoperative and postoperative corrected distance visual acuity(CDVA),keratometry simulated(K) reading,tomographic astigmatism and asphericity.All patients were evaluated using the Pentacam Scheimpflug system.RESULTS:The study evaluated 58 eyes.The mean followup was 16.81±10.8 mo.The CDVA(logM AR) improved from 0.5±0.20(20/60) to 0.3±0.21(20/40)(P〈0.01).The average K reduced from 49.87±7.01 to 47.34±4.90 D(P〈0.01).The asphericity changed from-0.60±0.86 to-0.23±0.67 D(P〈0.01).The mean preoperative tomographic astigmatism decreased from-8.0±3.45 to-4.53±2.52 D(P〈0.01).CONCLUSION:The new ICRS model with 140-degrees of arc effectively improve the visual acuity and reduce the high astigmatism usually found in patients with corneal ectasia.展开更多
AIM:To evaluate the clinical results after implantation of a new intrastromal corneal ring segment(ICRS)associated with photorefractive keratectomy(PRK)to correct high myopia(HM)patients with thin corneas.METHODS:We e...AIM:To evaluate the clinical results after implantation of a new intrastromal corneal ring segment(ICRS)associated with photorefractive keratectomy(PRK)to correct high myopia(HM)patients with thin corneas.METHODS:We evaluated 42 eyes of 23 HM patients that had ICRS implantation followed by PRK.The mean age of patients was 29.1±7.12 y(range 18 to 40 years old).Uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),keratometry,spherical equivalent,pachymetry,and aberrometry were compared using ANOVA with repeated measurements evaluated preoperatively and at last follow-up visit after the procedures.The refractive predictability and simulated/real corneal ablation were also assessed.RESULTS:The mean follow-up time after PRK was 6.8±1.6 mo.The mean preoperative UCVA improved from 20/800 preoperative to 20/100 after ICRS and 20/35 after PRK.The mean preoperative BCVA was 20/25(range from 20/30 to 20/20)and remained unchanged after ICRS implantation.Following the PRK the mean BCVA was 20/25(range from 20/30 to 20/20).The mean spherical equivalent decreased from-7.25±1.12(range-5.00 to-9.00)preoperatively to-3.32±1.0(range-2.00 to-5.00)postoperatively(P<0.001)after ICRS implantation and decreased from-2.44±1.51 preoperatively to 0.32±0.45(range-0.625 to 0.875)postoperatively(P<0.001)after PRK.The change in BCVA and topographic astigmatism was statistically significant(P<0.0001).CONCLUSION:ICRS in HM associated with PRK can be a tissue saving procedure and an alternative surgical option for correction of moderate to high myopia.展开更多
文摘AIM:To evaluate the clinical outcomes after subsequent implantation of a new intrastromal corneal ring segment(ICRS)model followed by an additional short-arc ICRS implant in keratoconus patients.METHODS:This retrospective single-arm cohort study evaluated 25 eyes of 21 keratoconus patients implanted with the new ICRS followed by 140-arch length ICRS(140-ICRS)implantation.Uncorrected distance visual acuity(UDVA,logMAR),corrected distance visual acuity(CDVA,logMAR),sphere,astigmatism,keratometry,spherical equivalent(SE),and asphericity were compared preoperatively and postoperatively after both ICRS implantation.RESULTS:The average follow-up time after 140-ICRS implantation was 6.40±2.20mo.The mean preoperative UDVA improved from 1.27±0.14 preoperative to 0.52±0.26 after both ICRS implantation(P=0.03).The mean sphere value reduced from-5.34±2.74 preoperatively to-2.06±1.84 postoperatively(P<0.001)after the first ICRS implantation and decreased to-0.59±1.54 postoperatively(P<0.001)after 140-ICRS implantation.The mean preoperative astigmatism was-3.72±1.56 and improved to-2.82±1.08 after the first ICRS implantation,and following the 140-ICRS implantation,the mean astigmatism was-1.37±0.67(P=0.001).The SE and asphericity changes were statistically significant(P<0.001).The researchers did not find intraoperative or postoperative complications for both procedures.CONCLUSION:The combination of 2 different ICRSs can efficiently regularize the cornea,reduce the SE,and improve visual acuity in selected keratoconus patients.
文摘AIM:To evaluate corneal parameters measured with a dual Scheimpflug analyzer in keratoconus patients implanted with intrastromal corneal ring segments(ICRS).METHODS:Fifty eyes of 40 keratoconus patients had Ferrara ICRS implantation from November 2010 to April2014.Uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),refraction,keratometry,asphericity,elevation,pachymetry,root mean square(RMS),spherical aberration and coma were studied.All patients were evaluated using a dual Scheimpflug system.RESULTS:The mean follow-up time after the procedure was 12.7mo.The mean UCVA improved from0.82 to 0.31(P〈0.001);the mean BCVA improved from0.42 to 0.05(P〈0.0001),the mean spherical refraction changed from-3.06 ±3.80 D to-0.80 ±2.5 D(P〈0.0001)and the mean refraction astigmatism reduced from-4.51 ±2.08 D to-2.26±1.18 D(P〈0.0001).The changes from preoperative to postoperative,in parameters of the anterior and posterior surface of the cornea,were statistically significant except the elevation posterior at the apex of the cornea and posterior asphericity.CONCLUSION:The implantation of Ferrara ICRS induces changes in both anterior and posterior surfaces of the cornea.
文摘AIM:To evaluate the clinical and tomographic outcomes after implantation of a new intrastromal corneal ring segment(ICRS) with 140-degrees of arc in eyes with corneal ectasia.METHODS:We evaluated patients with corneal ectasia implanted with Ferrara 140° ICRS from April 2010 to February 2015.Outcome measures included preoperative and postoperative corrected distance visual acuity(CDVA),keratometry simulated(K) reading,tomographic astigmatism and asphericity.All patients were evaluated using the Pentacam Scheimpflug system.RESULTS:The study evaluated 58 eyes.The mean followup was 16.81±10.8 mo.The CDVA(logM AR) improved from 0.5±0.20(20/60) to 0.3±0.21(20/40)(P〈0.01).The average K reduced from 49.87±7.01 to 47.34±4.90 D(P〈0.01).The asphericity changed from-0.60±0.86 to-0.23±0.67 D(P〈0.01).The mean preoperative tomographic astigmatism decreased from-8.0±3.45 to-4.53±2.52 D(P〈0.01).CONCLUSION:The new ICRS model with 140-degrees of arc effectively improve the visual acuity and reduce the high astigmatism usually found in patients with corneal ectasia.
文摘AIM:To evaluate the clinical results after implantation of a new intrastromal corneal ring segment(ICRS)associated with photorefractive keratectomy(PRK)to correct high myopia(HM)patients with thin corneas.METHODS:We evaluated 42 eyes of 23 HM patients that had ICRS implantation followed by PRK.The mean age of patients was 29.1±7.12 y(range 18 to 40 years old).Uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),keratometry,spherical equivalent,pachymetry,and aberrometry were compared using ANOVA with repeated measurements evaluated preoperatively and at last follow-up visit after the procedures.The refractive predictability and simulated/real corneal ablation were also assessed.RESULTS:The mean follow-up time after PRK was 6.8±1.6 mo.The mean preoperative UCVA improved from 20/800 preoperative to 20/100 after ICRS and 20/35 after PRK.The mean preoperative BCVA was 20/25(range from 20/30 to 20/20)and remained unchanged after ICRS implantation.Following the PRK the mean BCVA was 20/25(range from 20/30 to 20/20).The mean spherical equivalent decreased from-7.25±1.12(range-5.00 to-9.00)preoperatively to-3.32±1.0(range-2.00 to-5.00)postoperatively(P<0.001)after ICRS implantation and decreased from-2.44±1.51 preoperatively to 0.32±0.45(range-0.625 to 0.875)postoperatively(P<0.001)after PRK.The change in BCVA and topographic astigmatism was statistically significant(P<0.0001).CONCLUSION:ICRS in HM associated with PRK can be a tissue saving procedure and an alternative surgical option for correction of moderate to high myopia.