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Bradley J Randleman - One of the best experts on this subject based on the ideXlab platform.
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association between the percent tissue altered and post laser in situ keratomileusis Ectasia in eyes with normal preoperative topography
American Journal of Ophthalmology, 2014Co-Authors: Marcony R. Santhiago, David Smadja, Steven E. Wilson, Mário Luiz Ribeiro Monteiro, Beatriz De Abreu Fiuza Gomes, Glauco R Mello, Bradley J RandlemanAbstract:Purpose To investigate the association of a novel metric, percent tissue altered, with the occurrence of Ectasia after laser in situ keratomileusis (LASIK) in eyes with normal corneal topography and to compare this metric with other recognized risk factors. Design Retrospective case-control study. Methods The study included 30 eyes from 16 patients with bilateral normal preoperative Placido-based corneal topography that developed Ectasia after LASIK (Ectasia group) and 174 eyes from 88 consecutive patients with uncomplicated LASIK and at least 3 years of postoperative follow-up. The following metrics were evaluated: age, preoperative central corneal thickness, residual stromal bed, Ectasia Risk Score System scores, and percent tissue altered, derived from [PTA = (FT + AD)/CCT], where FT = flap thickness, AD = ablation depth, and CCT = preoperative central corneal thickness. Results In the Ectasia group, percent tissue altered ≥40 was the most prevalent factor (97%), followed by age P P Conclusions Percent tissue altered at the time of LASIK was significantly associated with the development of Ectasia in eyes with normal preoperative topography and was a more robust indicator of risk than all other variables in this patient population.
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validation of the Ectasia risk score system for preoperative laser in situ keratomileusis screening
American Journal of Ophthalmology, 2008Co-Authors: Bradley J Randleman, William Trattler, Doyle R StultingAbstract:Purpose To validate the Ectasia Risk Score System for identifying patients at high risk for developing Ectasia after laser in situ keratomileusis (LASIK). Design Retrospective case-control study. Methods Fifty eyes that developed Ectasia and 50 control eyes with normal postoperative courses after LASIK were analyzed and compared using the previously described Ectasia Risk Score System, which assigns points in a weighted fashion to the following variables: topographic pattern, predicted residual stromal bed (RSB) thickness, age, preoperative corneal thickness (CT), and manifest refraction spherical equivalent (MRSE). Results In this series, 46 (92%) eyes with Ectasia were correctly classified as being at high risk for the development of Ectasia, while three (6%) controls were incorrectly classified as being at high risk for Ectasia ( P −10 ). Significantly more eyes were classified as high risk by the Ectasia risk score than by traditional screening parameters relying on abnormal topography or RSB thickness less than 250 μ (92% vs 50%; P Conclusions The Ectasia Risk Score System is a valid and effective method for detecting eyes at risk for Ectasia after LASIK and represents a significant improvement over previously utilized screening strategies.
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risk assessment for Ectasia after corneal refractive surgery
Ophthalmology, 2008Co-Authors: Bradley J Randleman, Maria A Woodward, Michael J Lynn, Doyle R StultingAbstract:Purpose To analyze the epidemiologic features of Ectasia after excimer laser corneal refractive surgery, to identify risk factors for its development, and to devise a screening strategy to minimize its occurrence. Design Retrospective comparative and case–control study. Participants All cases of Ectasia after excimer laser corneal refractive surgery published in the English language with adequate information available through December 2005, unpublished cases seeking treatment at the authors' institution from 1998 through 2005, and a contemporaneous control group who underwent uneventful LASIK and experienced a normal postoperative course. Methods Evaluation of preoperative characteristics, including patient age, gender, spherical equivalent refraction, pachymetry, and topographic patterns; perioperative characteristics, including type of surgery performed, flap thickness, ablation depth, and residual stromal bed (RSB) thickness; and postoperative characteristics including time to onset of Ectasia. Main Outcome Measures Development of postoperative corneal Ectasia. Results There were 171 Ectasia cases, including 158 published cases and 13 unpublished cases evaluated at the authors' institution. Ectasia occurred after LASIK in 164 cases (95.9%) and after photorefractive keratectomy (PRK) in 7 cases (4.1%). Compared with controls, more Ectasia cases had abnormal preoperative topographies (35.7% vs. 0%; P −15 ), were significantly younger (34.4 vs. 40.0 years; P −7 ), were more myopic (−8.53 vs. −5.09 diopters; P −7 ), had thinner corneas before surgery (521.0 vs. 546.5 μm; P −7 ), and had less RSB thickness (256.3 vs. 317.3 μm; P −10 ). Based on subgroup logistic regression analysis, abnormal topography was the most significant factor that discriminated cases from controls, followed by RSB thickness, age, and preoperative corneal thickness, in that order. A risk factor stratification scale was created, taking all recognized risk factors into account in a weighted fashion. This model had a specificity of 91% and a sensitivity of 96% in this series. Conclusions A quantitative method can be used to identify eyes at risk for developing Ectasia after LASIK that, if validated, represents a significant improvement over current screening strategies.
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risk factors and prognosis for corneal Ectasia after lasik
Ophthalmology, 2003Co-Authors: Bradley J Randleman, Buddy Russell, M A Ward, Keith P Thompson, Doyle R StultingAbstract:Abstract Purpose To review cases of corneal Ectasia after laser in situ keratomileusis (LASIK), identify preoperative risk factors, and evaluate methods and success rates of visual rehabilitation for these cases. Design Retrospective nonrandomized comparative trial. Participants Ten eyes from seven patients identified as developing corneal Ectasia after LASIK, 33 previously reported Ectasia cases, and two control groups with uneventful LASIK and normal postoperative courses: 100 consecutive cases (first control group), and 100 consecutive cases with high myopia (> 8 diopters [D]) preoperatively (second control group). Methods Retrospective review of preoperative and postoperative data for each case compared with that of previously reported cases and cases with uneventful postoperative courses. Main outcome measures Preoperative refraction, topographic features, residual stromal bed thickness (RSB), time to the development of Ectasia, number of enhancements, final best-corrected visual acuity (BCVA), and method of final correction. Results Length of follow-up averaged 23.4 months (range, 6–48 months) after LASIK. Mean time to the development of Ectasia averaged 16.3 months (range, 1–45 months). Preoperative refraction averaged −8.69 D compared with −5.37 D for the first control group ( P = 0.005). Preoperatively, 88% of Ectasia cases met criteria for forme fruste keratoconus, compared with 2% of the first control group ( P P = 0.0000001). Seven eyes (70%) had RSB P = 0.0004) and the second control group (256.5 μm; P = 0.04). Seven eyes (70%) had enhancements. Only 10% of eyes lost more than one line of BCVA, and all patients eventually achieved corrected vision of 20/30 or better. One case required penetrating keratoplasty (10%), while all others required rigid gas-permeable contact lenses for correction. Conclusions Significant risk factors for the development of Ectasia after LASIK include high myopia, forme fruste keratoconus, and low RSB. All patients had at least one risk factor other than high myopia, and significant differences remained even when controlling for myopia. Multiple enhancements were common among affected cases, but their causative role remains unknown. We did not identify any patients who developed Ectasia without recognizable preoperative risk factors.
Doyle R Stulting - One of the best experts on this subject based on the ideXlab platform.
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validation of the Ectasia risk score system for preoperative laser in situ keratomileusis screening
American Journal of Ophthalmology, 2008Co-Authors: Bradley J Randleman, William Trattler, Doyle R StultingAbstract:Purpose To validate the Ectasia Risk Score System for identifying patients at high risk for developing Ectasia after laser in situ keratomileusis (LASIK). Design Retrospective case-control study. Methods Fifty eyes that developed Ectasia and 50 control eyes with normal postoperative courses after LASIK were analyzed and compared using the previously described Ectasia Risk Score System, which assigns points in a weighted fashion to the following variables: topographic pattern, predicted residual stromal bed (RSB) thickness, age, preoperative corneal thickness (CT), and manifest refraction spherical equivalent (MRSE). Results In this series, 46 (92%) eyes with Ectasia were correctly classified as being at high risk for the development of Ectasia, while three (6%) controls were incorrectly classified as being at high risk for Ectasia ( P −10 ). Significantly more eyes were classified as high risk by the Ectasia risk score than by traditional screening parameters relying on abnormal topography or RSB thickness less than 250 μ (92% vs 50%; P Conclusions The Ectasia Risk Score System is a valid and effective method for detecting eyes at risk for Ectasia after LASIK and represents a significant improvement over previously utilized screening strategies.
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risk assessment for Ectasia after corneal refractive surgery
Ophthalmology, 2008Co-Authors: Bradley J Randleman, Maria A Woodward, Michael J Lynn, Doyle R StultingAbstract:Purpose To analyze the epidemiologic features of Ectasia after excimer laser corneal refractive surgery, to identify risk factors for its development, and to devise a screening strategy to minimize its occurrence. Design Retrospective comparative and case–control study. Participants All cases of Ectasia after excimer laser corneal refractive surgery published in the English language with adequate information available through December 2005, unpublished cases seeking treatment at the authors' institution from 1998 through 2005, and a contemporaneous control group who underwent uneventful LASIK and experienced a normal postoperative course. Methods Evaluation of preoperative characteristics, including patient age, gender, spherical equivalent refraction, pachymetry, and topographic patterns; perioperative characteristics, including type of surgery performed, flap thickness, ablation depth, and residual stromal bed (RSB) thickness; and postoperative characteristics including time to onset of Ectasia. Main Outcome Measures Development of postoperative corneal Ectasia. Results There were 171 Ectasia cases, including 158 published cases and 13 unpublished cases evaluated at the authors' institution. Ectasia occurred after LASIK in 164 cases (95.9%) and after photorefractive keratectomy (PRK) in 7 cases (4.1%). Compared with controls, more Ectasia cases had abnormal preoperative topographies (35.7% vs. 0%; P −15 ), were significantly younger (34.4 vs. 40.0 years; P −7 ), were more myopic (−8.53 vs. −5.09 diopters; P −7 ), had thinner corneas before surgery (521.0 vs. 546.5 μm; P −7 ), and had less RSB thickness (256.3 vs. 317.3 μm; P −10 ). Based on subgroup logistic regression analysis, abnormal topography was the most significant factor that discriminated cases from controls, followed by RSB thickness, age, and preoperative corneal thickness, in that order. A risk factor stratification scale was created, taking all recognized risk factors into account in a weighted fashion. This model had a specificity of 91% and a sensitivity of 96% in this series. Conclusions A quantitative method can be used to identify eyes at risk for developing Ectasia after LASIK that, if validated, represents a significant improvement over current screening strategies.
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risk factors and prognosis for corneal Ectasia after lasik
Ophthalmology, 2003Co-Authors: Bradley J Randleman, Buddy Russell, M A Ward, Keith P Thompson, Doyle R StultingAbstract:Abstract Purpose To review cases of corneal Ectasia after laser in situ keratomileusis (LASIK), identify preoperative risk factors, and evaluate methods and success rates of visual rehabilitation for these cases. Design Retrospective nonrandomized comparative trial. Participants Ten eyes from seven patients identified as developing corneal Ectasia after LASIK, 33 previously reported Ectasia cases, and two control groups with uneventful LASIK and normal postoperative courses: 100 consecutive cases (first control group), and 100 consecutive cases with high myopia (> 8 diopters [D]) preoperatively (second control group). Methods Retrospective review of preoperative and postoperative data for each case compared with that of previously reported cases and cases with uneventful postoperative courses. Main outcome measures Preoperative refraction, topographic features, residual stromal bed thickness (RSB), time to the development of Ectasia, number of enhancements, final best-corrected visual acuity (BCVA), and method of final correction. Results Length of follow-up averaged 23.4 months (range, 6–48 months) after LASIK. Mean time to the development of Ectasia averaged 16.3 months (range, 1–45 months). Preoperative refraction averaged −8.69 D compared with −5.37 D for the first control group ( P = 0.005). Preoperatively, 88% of Ectasia cases met criteria for forme fruste keratoconus, compared with 2% of the first control group ( P P = 0.0000001). Seven eyes (70%) had RSB P = 0.0004) and the second control group (256.5 μm; P = 0.04). Seven eyes (70%) had enhancements. Only 10% of eyes lost more than one line of BCVA, and all patients eventually achieved corrected vision of 20/30 or better. One case required penetrating keratoplasty (10%), while all others required rigid gas-permeable contact lenses for correction. Conclusions Significant risk factors for the development of Ectasia after LASIK include high myopia, forme fruste keratoconus, and low RSB. All patients had at least one risk factor other than high myopia, and significant differences remained even when controlling for myopia. Multiple enhancements were common among affected cases, but their causative role remains unknown. We did not identify any patients who developed Ectasia without recognizable preoperative risk factors.
Marcony R. Santhiago - One of the best experts on this subject based on the ideXlab platform.
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Percent tissue altered and corneal Ectasia.
Current Opinion in Ophthalmology, 2016Co-Authors: Marcony R. SanthiagoAbstract:Purpose of review This article reviews the association of a novel metric, percentage tissue altered (PTA), with the occurrence of Ectasia after laser in-situ keratomileusis in eyes with normal corneal topography, and analyses the influence of the variables that comprise it, and its role on eyes with suspicious topography. Recent findings PTA is derived from [PTA = (FT + AD)/CCT] where FT = flap thickness, AD = ablation depth, and CCT = preoperative central corneal thickness. Our studies revealed that there is a robust relationship between high PTA and Ectasia risk in eyes with normal preoperative topography. PTA higher or equal to 40% presented the highest odds ratio and highest predictive capabilities for Ectasia risk than each of the variables that comprise it, residual stromal bed or age. Average thicker flaps alone were insufficient to create Ectasia unless coupled with greater ablation depths, meaning a high PTA. In eyes with suspicious topography, even low PTA value is sufficient to induce Ectasia. Summary This new metric, PTA, should be taken into account when screening patients for refractive surgery. Patients with normal topography or tomography, presenting a PTA higher or equal to 40% should be considered at higher risk for post laser in-situ keratomileusis Ectasia.
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Role of Percent Tissue Altered on Ectasia After LASIK in Eyes With Suspicious Topography
Journal of Refractive Surgery, 2015Co-Authors: Marcony R. Santhiago, David Smadja, Steven E. Wilson, Ronald R Krueger, Mário Luiz Ribeiro Monteiro, J. Bradley RandlemanAbstract:PURPOSE: To investigate the association of the percent tissue altered (PTA) with the occurrence of Ectasia after LASIK in eyes with suspicious preoperative corneal topography. METHODS: This retrospective comparative case-control study compared associations of reported Ectasia risk factors in 129 eyes, including 57 eyes with suspicious preoperative Placido-based corneal topography that developed Ectasia after LASIK (suspect Ectasia group), 32 eyes with suspicious topography that remained stable for at least 3 years after LASIK (suspect control group), and 30 eyes that developed Ectasia with bilateral normal topography (normal topography Ectasia group). Groups were subdivided based on topographic asymmetry into high- or low-suspect groups. The PTA, preoperative central corneal thickness (CCT), residual stromal bed (RSB), and age (years) were evaluated in univariate and multivariate analyses. RESULTS: Average PTA values for normal topography Ectasia (45), low-suspect Ectasia (39), high-suspect Ectasia (36), low-suspect control (32), and high-suspect control (29) were significantly different from one another in all comparisons (P < .003) except high- and low-suspect Ectasia groups (P = .033), and presented the highest discriminative capability of all variables evaluated. Age was only significantly different between the high-suspect Ectasia and normal topography Ectasia groups, and CCT was not significantly different between any groups. Stepwise logistic regression revealed the PTA as the most significant independent variable (P < .0001), with RSB the next most significant parameter. CONCLUSIONS: There remains a significant correlation between PTA values and Ectasia risk after LASIK, even in eyes with suspicious corneal topography. Less tissue alteration, or a lower PTA value, was necessary to induce Ectasia in eyes with more remarkable signs of topographic abnormality, and PTA provided better discriminative capabilities than RSB for all study populations.
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association between the percent tissue altered and post laser in situ keratomileusis Ectasia in eyes with normal preoperative topography
American Journal of Ophthalmology, 2014Co-Authors: Marcony R. Santhiago, David Smadja, Steven E. Wilson, Mário Luiz Ribeiro Monteiro, Beatriz De Abreu Fiuza Gomes, Glauco R Mello, Bradley J RandlemanAbstract:Purpose To investigate the association of a novel metric, percent tissue altered, with the occurrence of Ectasia after laser in situ keratomileusis (LASIK) in eyes with normal corneal topography and to compare this metric with other recognized risk factors. Design Retrospective case-control study. Methods The study included 30 eyes from 16 patients with bilateral normal preoperative Placido-based corneal topography that developed Ectasia after LASIK (Ectasia group) and 174 eyes from 88 consecutive patients with uncomplicated LASIK and at least 3 years of postoperative follow-up. The following metrics were evaluated: age, preoperative central corneal thickness, residual stromal bed, Ectasia Risk Score System scores, and percent tissue altered, derived from [PTA = (FT + AD)/CCT], where FT = flap thickness, AD = ablation depth, and CCT = preoperative central corneal thickness. Results In the Ectasia group, percent tissue altered ≥40 was the most prevalent factor (97%), followed by age P P Conclusions Percent tissue altered at the time of LASIK was significantly associated with the development of Ectasia in eyes with normal preoperative topography and was a more robust indicator of risk than all other variables in this patient population.
Perry S Binder - One of the best experts on this subject based on the ideXlab platform.
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evaluation of a risk factor scoring system for corneal Ectasia after lasik in eyes with normal topography
Journal of Refractive Surgery, 2010Co-Authors: Perry S Binder, William TrattlerAbstract:PURPOSE To assess a previously published risk score system for predicting postoperative LASIK Ectasia in eyes with normal preoperative topography. METHODS A retrospective review of one surgeon's LASIK database was performed for eyes with Randleman Ectasia risk scores based on patient age -8.00 diopters that had a minimum follow-up of 1 year. RESULTS Of 1702 eyes with myopic errors and normal topographies, 35 (2.0%) eyes had a combined risk score between 5 and 9 points, 92 (5.4%) eyes had a combined risk score of 4 or higher, and 208 (12.2%) eyes had a combined score of 3 or higher. None of these eyes developed Ectasia, whereas 3 eyes with preoperative topographic keratoconus with no other risk factors developed Ectasia. CONCLUSIONS The current risk score system would have eliminated 5.4% of eyes with 4 or more points from LASIK surgery, and would have also required the surgeon to advise an additional 6.8% of eyes with a score of 3 that they were at "moderate risk" and should "proceed with caution." In eyes with normal preoperative topographies, the scoring system may not accurately predict whether patients are at increased risk for developing postoperative LASIK Ectasia.
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analysis of Ectasia after laser in situ keratomileusis risk factors
Journal of Cataract and Refractive Surgery, 2007Co-Authors: Perry S BinderAbstract:Purpose To examine a database of laser in situ keratomileusis (LASIK) procedures for preoperative and operative factors assumed to increase the risk for developing post-LASIK Ectasia. Setting Private clinical practice. Methods A computer database was queried for eyes that had LASIK for myopic refractive errors with the following characteristics: preoperative corneal thickness 500 μm or less, mean keratometry greater than 47.0 diopters (D), patient age 25 years or younger, attempted correction greater than −8.0 D, refractive astigmatism not with-the-rule and greater than 2.0 D, and residual stromal bed thickness (RST) 250 μm or less. Flap thickness and RST were measured using ultrasound pachymetry. All recorded information was exported to MS Excel and analyzed for eyes that had Ectasia. Results Of the 9700 eyes in the database, none with the above characteristics developed Ectasia over mean follow-up periods exceeding 2 years. Seven eyes had multiple risk factors without Ectasia. Three eyes with abnormal preoperative topography developed Ectasia. Conclusions Individual preoperative and operative factors did not in and of themselves increase the risk for Ectasia. Unmeasured and unknown factors that affect the individual cornea's biomechanical stability, in combination with some suspected risk factors as well as the current inability to identify corneas at risk for developing ectatic disorders, probably account for most eyes that develop Ectasia today.
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Ectasia after laser in situ keratomileusis
Journal of Cataract and Refractive Surgery, 2003Co-Authors: Perry S BinderAbstract:Abstract Eighty-five cases of post laser in situ keratomileusis Ectasia were reviewed and analyzed. Cases of keratoconus or forme fruste keratoconus were eliminated; many remaining case reports lacked key information. The current literature is unable to define a specific residual corneal thickness or a range of preoperative corneal thickness that would put an eye at risk for developing Ectasia. The most logical cause for eyes without preexisting pathology to develop Ectasia is a postablation stromal thickness that is mechanically unstable; this “minimal” thickness is probably specific to each eye. The preoperative and postoperative corneal thickness, measured flap thickness, and microkeratome and laser parameters used in a given case are required to determine the range of residual corneal thickness that puts the eye at risk for developing Ectasia. Other as yet undetermined factors may play a role in the development of this complication.
William Trattler - One of the best experts on this subject based on the ideXlab platform.
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evaluation of a risk factor scoring system for corneal Ectasia after lasik in eyes with normal topography
Journal of Refractive Surgery, 2010Co-Authors: Perry S Binder, William TrattlerAbstract:PURPOSE To assess a previously published risk score system for predicting postoperative LASIK Ectasia in eyes with normal preoperative topography. METHODS A retrospective review of one surgeon's LASIK database was performed for eyes with Randleman Ectasia risk scores based on patient age -8.00 diopters that had a minimum follow-up of 1 year. RESULTS Of 1702 eyes with myopic errors and normal topographies, 35 (2.0%) eyes had a combined risk score between 5 and 9 points, 92 (5.4%) eyes had a combined risk score of 4 or higher, and 208 (12.2%) eyes had a combined score of 3 or higher. None of these eyes developed Ectasia, whereas 3 eyes with preoperative topographic keratoconus with no other risk factors developed Ectasia. CONCLUSIONS The current risk score system would have eliminated 5.4% of eyes with 4 or more points from LASIK surgery, and would have also required the surgeon to advise an additional 6.8% of eyes with a score of 3 that they were at "moderate risk" and should "proceed with caution." In eyes with normal preoperative topographies, the scoring system may not accurately predict whether patients are at increased risk for developing postoperative LASIK Ectasia.
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validation of the Ectasia risk score system for preoperative laser in situ keratomileusis screening
American Journal of Ophthalmology, 2008Co-Authors: Bradley J Randleman, William Trattler, Doyle R StultingAbstract:Purpose To validate the Ectasia Risk Score System for identifying patients at high risk for developing Ectasia after laser in situ keratomileusis (LASIK). Design Retrospective case-control study. Methods Fifty eyes that developed Ectasia and 50 control eyes with normal postoperative courses after LASIK were analyzed and compared using the previously described Ectasia Risk Score System, which assigns points in a weighted fashion to the following variables: topographic pattern, predicted residual stromal bed (RSB) thickness, age, preoperative corneal thickness (CT), and manifest refraction spherical equivalent (MRSE). Results In this series, 46 (92%) eyes with Ectasia were correctly classified as being at high risk for the development of Ectasia, while three (6%) controls were incorrectly classified as being at high risk for Ectasia ( P −10 ). Significantly more eyes were classified as high risk by the Ectasia risk score than by traditional screening parameters relying on abnormal topography or RSB thickness less than 250 μ (92% vs 50%; P Conclusions The Ectasia Risk Score System is a valid and effective method for detecting eyes at risk for Ectasia after LASIK and represents a significant improvement over previously utilized screening strategies.
