Predictive Factors for Magnetic Resonance Imaging Changes Suggestive of Demyelination in Adult Patients with Uveitis Scanned Prior to Commencing Adalimumab Therapy.

PURPOSE: To report the predictive clinical factors for abnormal magnetic resonance imaging (MRI) scans suggestive of demyelination by analysis of MRI's performed for adult non-infectious uveitic patients prior to commencing adalimumab therapy. METHODS: Retrospective case review of 240 patients was conducted in a single tertiary institution between November 2017 and March 2020. Aetiology of underlying disease, clinical characteristics, and MRI outcomes were analysed. RESULTS: The presence of bilateral idiopathic intermediate uveitis (IIU) (p = .0048) and neurological symptoms (p = .028) were highly predictive of an abnormal MRI strongly suggestive of demyelination (MRSSD); 5 out of 64 scans (7.8%) with these clinical characteristics had MRSSD. CONCLUSIONS: Tumor necrosis factor antagonist-induced demyelination is a concern in adalimumab use. We propose an MRI screening protocol to identify those at high risk of demyelination; positive results can be maximised by screening all patients with IIU and those with neurological symptoms.

Treatment of chronic diabetic macular oedema with intravitreal fluocinolone acetonide implant; real-life analysis of outcomes during overall treatment period.

PURPOSE: To assess the clinical efficacy of the fluocinolone acetonide (FA) intravitreal implant (Iluvien, Alimera Sciences) over a 12-month period in a population resistant to treatment with first-line anti-VEGF agents. METHODS: This study is a retrospective cohort study assessing functional and anatomical outcomes in 13 eyes of 12 patients treated for diabetic macular oedema (DMO) with a single fluocinolone implant (FA) (Iluvien) under real-world conditions. The follow-up period includes the time of first intravitreal treatment (incl anti-VEGF or short-lasting steroids) given until 12 months post FA implant insertion. Primary outcomes were best corrected visual acuity (BCVA), measured using the modified Early Treatment Diabetic Retinopathy Study (ETDRS) grading scale, and central foveal thickness (CFT), measured using Topcon 3DOCT-2000 (Topcon Inc) SD-OCT imaging. Mean BCVA and CFT were measured before anti-VEGF treatment, after anti-VEGF treatment, at the time of Iluvien implant insertion, and 6 and 12 months after Iluvien implant insertion. The t-paired sample test was used to ascertain statistical significance of changes in comparison of two samples while the ANOVA analysis was used in comparison of three or more samples. RESULTS: The baseline BCVA (SD) of the cohort prior to initiation of anti-VEGF treatment was 47.45 (12.27) ETDRS letters whilst the mean CFT (SD) was 579 (203) microns. Following completion of anti-VEGF therapy, the mean improvement in vision was 8.9 ETDRS letters (p = 0.1) whilst the mean reduction in CFT was 197 microns (p = 0.028). Mean BCVA (SD) at the time of insertion of the FA implant was 55.15 (11.16) ETDRS letters and mean (SD) CFT at time of insertion of the FA was 454.62 µm (109.51). Following the 12-month treatment period with the FA implant, BCVA (SD) was 62.15 (10.25) ETDRS letters (p = 0.0331) and the mean (SD) CFT was 404.36 µm (142.92), a change of -50.26 µm from baseline (p = 0.0369). CONCLUSIONS: This study has shown that statistically significant improvements in BCVA and CFT can be achieved over a 12-month period with the Iluvien implant. The implant has been shown to be a safe option in the treatment of DMO and may have a role to play in achieving good functional and anatomical outcomes in DMO while also reducing the frequency of follow-up appointments required to maintain stable vision in the working-age population.

Characterization of Ebola Virus-Associated Eye Disease.

Importance: Survivors of Ebola virus disease (EVD) may experience ocular sequelae. Comparison with antibody-negative individuals from the local population is required to characterize the disease. Objective: To assess features of ophthalmic disease specific to EVD. Design, Setting, and Participants: This baseline cross-sectional analysis of survivors of EVD and their close contacts was conducted within PREVAIL III, a 5-year, longitudinal cohort study. Participants who enrolled at John F. Kennedy Medical Center in Liberia, West Africa from June 2015 to March 2016 were included in this analysis. Close contacts were defined as household members or sex partners of survivors of EVD. Data were analyzed from July 2016 to July 2020. Exposures: All participants, both survivors and close contacts, underwent testing of IgG antibody levels against Ebola virus surface glycoprotein. Main Outcomes and Measures: Ocular symptoms, anterior and posterior ophthalmologic examination findings, and optical coherence tomography images were compared between antibody-positive survivors and antibody-negative close contacts. Results: A total of 564 antibody-positive survivors (320 [56.7%] female; mean [SD] age, 30.3 [14.0] years) and 635 antibody-negative close contacts (347 [54.6%] female; mean [SD] age, 25.8 [15.5] years) were enrolled in this study. Survivors were more likely to demonstrate color vision deficit (28.9% vs 19.0%, odds ratio [OR], 1.6; 95% CI, 1.2-2.1) and lower intraocular pressure (12.4 vs 13.5 mm Hg; mean difference, -1.2 mm Hg; 95% CI, -1.6 to -0.8 mm Hg) compared with close contacts. Dilated fundus examination revealed a higher percentage of vitreous cells (7.8% vs 0.5%; OR, 16.6; 95% CI, 5.0-55.2) and macular scars (4.6% vs 1.6%; OR, 2.8; 95% CI, 1.4-5.5) in survivors than in close contacts. Uveitis was present in 26.4% of survivors and 12.1% of close contacts (OR, 2.4; 95% CI, 1.8-3.2). Among all participants with uveitis, survivors were more likely than close contacts to have intermediate uveitis (34.2% vs 6.5% of all cases; OR, 7.8; 95% CI, 3.1-19.7) and had thicker mean central subfield thickness on optical coherence tomography (222 vs 212 µm; mean difference, 14.4 µm; 95% CI, 1.9-26.9 µm). Conclusions and Relevance: In this cross-sectional study, survivors of EVD had a distinct spectrum of ocular and neuro-ophthalmologic findings compared with close contacts that potentially require medical and surgical treatment.

Logistic Regression Classification of Primary Vitreoretinal Lymphoma versus Uveitis by Interleukin 6 and Interleukin 10 Levels.

PURPOSE: To assess the diagnostic performance and generalizability of logistic regression in classifying primary vitreoretinal lymphoma (PVRL) versus uveitis from intraocular cytokine levels in a single-center retrospective cohort, comparing a logistic regression model and previously published Interleukin Score for Intraocular Lymphoma Diagnosis (ISOLD) scores against the interleukin 10 (IL-10)-to-interleukin 6 (IL-6) ratio. DESIGN: Retrospective cohort study. PARTICIPANTS: Patient histories, pathology reports, and intraocular cytokine levels from 2339 patient entries in the National Eye Institute Histopathology Core database. METHODS: Patient diagnoses of PVRL versus uveitis and associated aqueous or vitreous IL-6 and IL-10 levels were collected retrospectively. From these data, cytokine levels were compared between diagnoses with the Mann-Whitney U test. A logistic regression model was trained to classify PVRL versus uveitis from aqueous and vitreous IL-6 and IL-10 samples and compared with ISOLD scores and IL-10-to-IL-6 ratios. MAIN OUTCOME MEASURES: Area under the receiver operating characteristic curve (AUC) for each classifier and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) at the optimal cutoff (maximal Youden index) for each classifier. RESULTS: Seventy-seven lymphoma patients (10 aqueous samples, 67 vitreous samples) and 84 uveitis patients (19 aqueous samples, 65 vitreous samples) treated between October 5, 1999, and September 16, 2015, were included. Interleukin 6 levels were higher and IL-10 levels were lower in uveitis patients compared with lymphoma patients (P < 0.01). For vitreous samples, the logistic regression model, ISOLD score, and IL-10-to-IL-6 ratio achieved AUCs of 98.3%, 97.7%, and 96.3%, respectively. Sensitivity, specificity, PPV, and NPV at the optimal cutoffs for each classifier were 94.2%, 96.9%, 97%, and 94% for the logistic regression model; 92.7%, 100%, 100%, and 92.9% for the ISOLD score; and 94.2%, 95.3%, 95.6%, and 93.9% for the IL-10-to-IL-6 ratio. All models achieved complete separation between uveitis and lymphoma in the aqueous data set. CONCLUSIONS: The accuracy of the logistic regression model and generalizability of the ISOLD score to an independent patient cohort suggest that intraocular cytokine analysis by logistic regression may be a promising adjunct to cytopathologic analysis, the gold standard, for the early diagnosis of primary vitreoretinal lymphoma. Further validation studies are merited.

Immunohistochemical characterization of feline lymphoplasmacytic anterior uveitis.

OBJECTIVE: To characterize the immune cells present in different forms of feline anterior uveitis. SAMPLES: Eyes were obtained from 49 cats diagnosed with chronic idiopathic lymphoplasmacytic anterior uveitis, 7 cats with feline infectious peritonitis (FIP), and 9 cats euthanized for nonocular disease. METHODS: H&E sections were scored on the level of infiltrate in the anterior uvea. Immunohistochemistry was performed for FoxP3, CD3, and IL-17A, and positive cells were quantified in multiple images of each sample. A generalized estimating equation tested for an association between the level of inflammation and the prevalence of these cell types. RESULTS: Cells stained positive for IL-17A in idiopathic uveitis but not in FIP samples. We found significantly fewer FoxP3+ and CD3+ cells in low-grade compared with high-grade inflammation in idiopathic uveitis or FIP samples (P values all <.005), but no difference between FIP and high-grade samples. CONCLUSIONS: Idiopathic, but not FIP-associated, uveitis appears to have Th17 cell involvement. The numbers of FoxP3+ and CD3+ T-cells present appear directly correlated; thus, the severity of disease does not appear directly determined by the numbers of regulatory cells.

Gradient Boosted Decision Tree Classification of Endophthalmitis Versus Uveitis and Lymphoma from Aqueous and Vitreous IL-6 and IL-10 Levels.

PURPOSE: To investigate the effectiveness of gradient boosting to classify endophthalmitis versus uveitis and lymphoma by intraocular cytokine levels. METHOD: Patient diagnoses and aqueous and vitreous levels of interleukin (IL)-6 and IL-10 were retrospectively extracted from a National Eye Institute Histopathology Core database and compared by Kruskal-Wallis and post hoc Dunn tests. A gradient-boosted decision tree classifier was trained to differentiate endophthalmitis versus uveitis and lymphoma from vitreous IL-6 and IL-10, vitreous IL-6 only, and aqueous IL-6 only data sets; and was tested with 80-20 train-test split and 3-fold cross-validation of the training set. RESULTS: Seven endophthalmitis, 29 lymphoma, and 49 uveitis patients were included. IL-6 was higher in endophthalmitis than uveitis (P = 0.0713 aqueous, 0.0014 vitreous) and lymphoma (P = 0.0032 aqueous, 0.0001 vitreous). IL-10 was significantly higher in lymphoma than uveitis (P = 0.0017 aqueous, 0.0014 vitreous). Three-fold cross validation demonstrated 95% ± 5%, 95% ± 4%, and 97% ± 5% predictive accuracy for vitreous IL-6 and IL-10, vitreous IL-6 only, and aqueous IL-6 only data sets. Upon validation with the testing set, vitreous IL-6 and IL-10 and aqueous IL-6 only data sets achieved 100% predictive accuracy and vitreous IL-6 only data achieved 93% predictive accuracy with 100% sensitivity, 92% specificity, and an area under the receiver operating characteristic curve (ROC/AUC) of 96%. CONCLUSIONS: With limited sample size, gradient boosting can differentiate endophthalmitis from uveitis and lymphoma by IL-6 and IL-10 with high sensitivity and specificity; however, a larger cohort is needed for further validation.

Cytomegalovirus retinitis complicating combination therapy with rituximab and fludarabine.

Cytomegalovirus (CMV) retinitis is exceptionally rare outside the clinical context of acquired immunodeficiency syndrome and organ allografting. In a population where seropositivity for past CMV infection exceeded 90 %, CMV retinitis was observed in five of 138 patients (3.6 %) receiving fludarabine-containing regimens together with rituximab, which was significantly more frequent than in 141 patients receiving fludarabine-containing regimens alone, where no case was observed (P = 0.029). Treatment of CMV retinitis comprised both intravitreal and systemic ganciclovir/foscarnet. Upon recovery, secondary retinal atrophy occurred in all patients, leading to blindness in 86 % of affected eyes. CMV retinitis is an important complication in patients receiving concomitant rituximab and fludarabine-containing regimens.

Sequential therapy with ranibizumab and dexamethasone intravitreal implant is better than dexamethasone monotherapy for macular oedema due to retinal vein occlusion.

PURPOSE: To evaluate the efficacy and safety of sequential therapy with ranibizumab followed by dexamethasone intravitreal implant compared with dexamethasone monotherapy for macular oedema (MO) secondary to retinal vein occlusion (RVO). METHODS: In this retrospective interventional study, the medical records of subjects with MO due to RVO who received either ranibizumab followed by dexamethasone intravitreal implant (Group 1) or dexamethasone-implant monotherapy (Group 2) were included. Primary outcome was the proportion of subjects who exhibited best-corrected visual acuity (VA) gain and resolution of MO within 6 months. RESULTS: Thirty-three eyes were included (17 in Group 1, 16 in Group 2). More subjects in Group 1 exhibited a VA gain of at least 0.5 (LogMAR units hereafter) than Group 2 (29% vs 0%, p=0.044). The speed of VA gain was greater in Group 1 (1.4±0.8 months vs 2.7±1.4 months, p=0.020). MO was controlled in more subjects in Group 1 at all measured time intervals, and this difference was statistically significant at 3 months and 4 months. Subjects with branch RVO experienced VA gain more rapidly if they were from Group 1 (p=0.023). CONCLUSIONS: Sequential therapy was found to be more effective than dexamethasone monotherapy in treating MO due to RVO.

Occlusion therapy in amblyopia: an experience from Hong Kong.

OBJECTIVES. To review the results of patching for amblyopia management in Hong Kong. DESIGN. Retrospective case series. SETTING. Regional hospital, Hong Kong. PATIENTS. Records of all patients attending Paediatric Ophthalmology Clinic at United Christian Hospital, Hong Kong from 1 January 2009 to 31 March 2009 were retrospectively reviewed. Records of all children who underwent patching for amblyopia in the study period were evaluated. RESULTS. The mean age of 50 children (50 eyes) was 4 (standard deviation, 1; range, 2-7) years and mean pretreatment visual acuity was 0.35 (0.15; 0.02-0.63) [~20/60]. The values for mean, standard deviation, and range of treatment duration were 27, 16, 4-67 months respectively, and corresponding values for prescribed patching per day were 4, 1, 2-8 hours. The mean, standard deviation, and range of visual acuity at final post-treatment assessment were 0.66, 0.16, 0.1-1.0 (~20/30), respectively. The overall success rate (ie final visual acuity >0.7 or 20/30) was 62%. Children with moderate amblyopia (20/40-20/80) and severe amblyopia (20/100-20/400) had success rates of 74% and 55%, respectively. The mean visual acuity improvements for moderate and severely amblyopic children were 2.3 lines and 5.8 lines, respectively. The mean, standard deviation, and range of patching prescriptions for moderate and severely amblyopic children were 5, 1, 2-7 hours and 5, 1, 3-6 hours, respectively. Recurrence ensued in 7% of the children with moderate amblyopia and 46% of those with severe amblyopia. Reported compliance was good (>75% of the time) in 68% of the children. CONCLUSION. Occlusion therapy is the mainstay of treatment in Hong Kong. The overall success rate was comparable to that achieved in the Amblyopia Treatment Study. Recurrence was more common in patients with severe amblyopia, for whom maintenance therapy may reduce the risk of recurrence. The duration of treatment was much longer in our locality than in western countries. Reported compliance was suspicious possibly due to traditional cultural contexts. It is important to emphasise compliance to all parents.

Photorefractive keratectomy (PRK) versus laser assisted in situ keratomileusis (LASIK) for hyperopia correction.

BACKGROUND: Hyperopia, or hypermetropia (also known as long-sightedness or far-sightedness), is the condition where the unaccommodating eye brings parallel light to a focus behind the retina instead of on it. Hyperopia can be corrected with both non-surgical and surgical methods, among them photorefractive keratectomy (PRK) and laser assisted In situ keratomileusis (LASIK). There is uncertainty as to whether hyperopic-PRK or hyperopic-LASIK is the better method. OBJECTIVES: The objectives of this review were to determine whether PRK or LASIK leads to more reliable, stable and safe results when correcting a hyperopic refractive error. SEARCH METHODS: We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 2), MEDLINE (January 1950 to February 2012), EMBASE (January 1980 to February 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to February 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). There were no date or language restrictions in the electronic searches for trials. The electronic databases were last searched on 17 February 2012. When trials are included in the review we will search the reference lists of the studies included in the review for information about further trials. We will use the Science Citation Index to search for papers that cite any studies included in this review. We did not handsearch journals or conference proceedings specifically for this review. SELECTION CRITERIA: We planned to include only randomised controlled trials (RCTs) comparing PRK against LASIK for correction of hyperopia and then perform a sensitivity analysis of pre- and post-millennial trials since this is the mid-point in the history of both PRK and LASIK. DATA COLLECTION AND ANALYSIS: We did not identify any studies that met the inclusion criteria for this review. MAIN RESULTS: As no studies met the inclusion criteria for this review, we discussed the results of non-randomised trials comparing hyperopic-PRK with hyperopic-LASIK. AUTHORS' CONCLUSIONS: No robust, reliable conclusions could be reached, but the non-randomised trials reviewed appear to be in agreement that hyperopic-PRK and hyperopic-LASIK are of comparable efficacy. High quality, well-planned open RCTs are needed in order to obtain a robust clinical evidence base.

Simultaneous spectral domain OCT and fundus autofluorescence imaging of the macula and microperimetric correspondence after successful repair of rhegmatogenous retinal detachment.

BACKGROUND/AIMS: To evaluate the ultrastructural changes in the macula after successful repair of rhegmatogenous retinal detachment (RRD) using simultaneous spectral domain optical coherence tomography (sdOCT) and fundus autofluorescence (FAF) imaging and to perform functional correlations with microperimetry. METHODS: Simultaneous sdOCT and FAF imaging were performed using a combined sdOCT-confocal scanning laser ophthalmoscope (cSLO) system. Microperimetry was performed in a subgroup of these patients. RESULTS: 17 patients with macular-on RRD and 20 with macular-off RRD were recruited. sdOCT images revealed disruption of the external limiting membrane, inner segment/outer segment junction or the Verhoeff membrane in 16 eyes (43.2%). The presence of any or more of these disruptions was significantly associated with a poor postoperative best-corrected visual acuity (BCVA) (p<0.001). Patients with abnormal FAF were also associated with poor postoperative BCVA (p<0.001). However, there was a generally poor correspondence between the localisation of ultrastructural abnormalities as detected by sdOCT and FAF changes. Areas of decreased microperimetric sensitivity corresponded well with the ultrastructural changes and abnormal FAF. CONCLUSIONS: FAF changes may lag behind ultrastructural changes in the OCT, some of which may reverse with the passage of time. The present study demonstrates the ultrastructural changes assessed with simultaneous FAF and sdOCT and their relation with visual outcome.

Photorefractive keratectomy (PRK) versus laser assisted in situ keratomileusis (LASIK) for hyperopia correction.

BACKGROUND: Hyperopia, or hypermetropia (also known as long-sightedness or far-sightedness), is the condition where the unaccommodating eye brings parallel light to a focus behind the retina instead of on it. Hyperopia can be corrected with both non-surgical and surgical methods, among them photorefractive keratectomy (PRK) and laser assisted In situ keratomileusis (LASIK). There is uncertainty as to whether hyperopic-PRK or hyperopic-LASIK is the better method. OBJECTIVES: The objectives of this review were to determine whether PRK or LASIK leads to more reliable, stable and safe results when correcting a hyperopic refractive error. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2008), MEDLINE (January 1950 to January 2009), EMBASE (January 1980 to January 2009) and LILACS (January 1982 to January 2009). There were no language or date restrictions in the search for trials. The electronic databases were last searched on 13 January 2009. We also searched the reference lists of the studies included in the review for information about further trials and used the Science Citation Index to search for papers that cite any studies included in this review. We did not handsearch journals or conference proceedings specifically for this review. SELECTION CRITERIA: We planned to include only randomised controlled trials (RCTs) comparing PRK against LASIK for correction of hyperopia and then perform a sensitivity analysis of pre- and post-millennial trials since this is the mid-point in the history of both PRK and LASIK. DATA COLLECTION AND ANALYSIS: We did not identify any studies that met the inclusion criteria for this review. MAIN RESULTS: As no studies met the inclusion criteria for this review, we discussed the results of non-randomised trials comparing hyperopic-PRK with hyperopic-LASIK. AUTHORS' CONCLUSIONS: No robust, reliable conclusions could be reached, but the non-randomised trials reviewed appear to be in agreement that hyperopic-PRK and hyperopic-LASIK are of comparable efficacy. High quality, well-planned open RCTs are needed in order to obtain a robust clinical evidence base.

The use of the Ocular Response Analyser to determine corneal hysteresis in eyes before and after excimer laser refractive surgery.

PURPOSE: To compare corneal biomechanical parameters and two measures of intraocular pressure (IOP) in eyes before and after excimer laser refractive surgery, with the Ocular Response Analyser (ORA). MATERIALS AND METHODS: Eighty normal eyes of 41 patients undergoing excimer laser refractive surgery in Birmingham, U.K. were recruited into three groups: Laser Assisted-Epithelial Keratomileusis (LASEK) (Myopes), Laser Assisted in Situ Keratomileusis (LASIK) (myopes) and LASIK (hyperopes). The preop and 3 months postop Goldmann correlated IOP (IOPg), corneal compensated IOP (IOPcc), corneal hysteresis (CH), and corneal resistance factor (CRF) were measured by the ORA. Central corneal thickness (CCT) was measured using ultrasonic pachymeter. The differences of the changes in IOPg, IOPcc, CH, CRF and CCT between the three groups were estimated. A General Linear Model was selected to investigate the influence of gender, age, initial conditions (CH, CRF, CCT, IOPcc and IOPg) and changes in CCT on the measured IOP. RESULTS: The differences between the mean IOPg, CH and CRF after refractive surgery were statistically significant for all three groups. The hyperopic LASIK group had a significantly smaller change compared to the other groups (which had no statistical significance). The preop IOPg, preop CH and gender were significant predictors of the changes in measured pressure and biomechanical parameters after surgery in the myopic groups only. CONCLUSION: CH and CRF were found to decrease after both myopic and hyperopic refractive surgery. CH and CRF measurement may prove important tools to clarify the role of corneal biomechanics for refractive surgery.

Aspheric ablation with the Nidek EC-5000 CX II with OPD-Scan objective analysis.

PURPOSE: To analyze the efficacy, predictability, stability, and safety of laser in situ keratomileusis (LASIK) to correct myopia and myopic astigmatism using the Nidek EC-5000 CX II laser and the Customized Aspheric Transition Zone (CATz) profile. METHODS: We conducted a retrospective analysis of 100 eyes (50 patients) with myopic astigmatism. A CATz profile was used in all eyes (profile 4) with an ablation zone of 5 mm and a transition zone of 9 mm, using Nidek FinalFit software. RESULTS: Average patient age was 39 years (range 21 to 69 yr). Preoperative mean spherical equivalent refraction was -4.70 +/- 2.53 D (range -11.88 to -0.50 D), mean preoperative sphere was -4.31 +/- 2.53 D (range -11.25 to -0.25 D), and mean preoperative cylinder was -0.78 +/- 0.69 D (range -3.25 to 0). Postoperative mean spherical equivalent refraction at 6 months was 0.12 +/- 0.53 D (range -1.63 to +0.88 D), mean postoperative sphere was 0.02 +/- 0.56 D (range -1.50 to +2.00 D), and mean postoperative cylinder was -0.29 +/- 0.50 D (range 0 to -1.75 D). Uncorrected visual acuity was 6/6 or better in 58% (58 eyes) and better than 6/12 in 93% (93 eyes). CONCLUSION: LASIK with the Nidek EC-5000 CX II laser and the CATz profile was effective, reasonably predictable, stable, and safe for correction of myopic astigmatism with a spherical component between -0.25 and -11.25 D, and a cylindrical component up to 3.25 D, using the techniques in this study. Astigmatism was undercorrected with the current algorithm.

Higher order aberrations with aspheric ablations using the Nidek EC-5000 CX II laser.

PURPOSE: To analyze the change in higher order aberrations in myopic and myopic astigmatic eyes following an aspheric ablation profile for laser in situ keratomileusis (LASIK) using a Nidek EC-5000 CX II excimer laser system. METHODS: We performed a retrospective audit of 38 eyes (19 patients) with myopia and myopic astigmatism. A customized aspheric transition zone profile (CATz) was used in all eyes (profile 4) with an ablation zone of 5 mm and a transition zone of 9 mm using FinalFit software and a Nidek EC-5000 CX II excimer laser system. RESULTS: Mean higher order aberrations (RMS) increased from 0.42 microm at baseline to 0.57 microm at 6-month follow-up. Mean spherical aberrations (Z12) increased from 0.02 microm at baseline to 0.33 microm after LASIK. Mean spherical aberration defocus equivalent (DEQ) increased from 0.56 microm at baseline to 1.54 at 6 months after surgery. Mean trefoil (Z6) was -0.11 microm at baseline and -0.14 microm at the 3-month examination. Mean coma (Z7) was -0.09 microm at baseline and -0.10 microm after surgery. Mean coma (Z8) was -0.03 at baseline and 0 at the 3-month examination. Mean trefoil (Z9) was -0.03 at baseline and -0.12 at the 3-month examination. CONCLUSION: The amount of postoperative higher order aberrations in these myopic eyes was acceptable. However, the clinical significance of these numerical changes in aberrations is not known.

Correlation of Nidek OPD-Scan objective refraction with subjective refraction.

PURPOSE: The aim of this study was to quantify how closely the Nidek OPD-Scan objective refraction correlated with subjective refraction. METHODS: A retrospective audit of the preoperative refraction of 80 myopic and myopic astigmatic eyes before laser in situ keratomileusis (LASIK) or laser supepithelial keratomileusis (LASEK) was performed. Objective refraction in the 5-mm zone was performed using a Nidek OPD-Scan. Subjective refraction was performed by a senior optometrist. Statistical analysis of sphere, cylinder, and spherical equivalent refraction measurements was then performed. RESULTS: Spherical measurements correlated well with a linear regression equation, with a correlation coefficient of 0.97. Cylinder measurements correlated less well, with a correlation coefficient of 0.85. Spherical equivalent refraction measurements correlated well, with a correlation coefficient of 0.97. Analyzing the numerical difference between each objective refraction and its corresponding subjective refraction, the majority of values were only 0.50 D apart for sphere, cylinder, and spherical equivalent refraction. CONCLUSION: There was good correlation between objective OPD-Scan and subjective refraction, especially for sphere and spherical equivalent refraction measurements, with regression gradients and correlation coefficients close to 1.