Corneal pseudoectasia: a case series.

OBJECTIVE: To raise awareness of conditions that can tomographically mimic corneal ectasia and describe the actions required to avoid misdiagnosis. METHODS: We report a retrospective case series of seven patients presenting at two tertiary care centers in Israel with a presumed diagnosis of keratoconus or post-refractive ectasia. Upon further examination, the ectasia diagnosis was reconsidered and eventually ruled out. RESULTS: Included were ten eyes of seven patients. Cases included bilateral diffuse Salzmann's nodular degeneration, ophthalmoplegia with strabismus which precluded proper fixation during the acquisition of tomography images, two cases of incorrect Pentacam parameter settings, a patient with a history of hyperopic laser-assisted in situ keratomileusis (LASIK) treatment in one eye and myopic LASIK in the fellow eye, a case of old post-photorefractive keratectomy (PRK) stromal haze, and a patient with posterior polymorphous corneal dystrophy. CONCLUSIONS: Tomography patterns mimicking corneal ectasia can appear in patients without ectatic pathology. The comprehensive ophthalmologist should be aware of such cases as they may substantially alter the treatment course and prognosis of these patients.

Use of machine learning to achieve keratoconus detection skills of a corneal expert.

PURPOSE: To construct an automatic machine-learning derived algorithm discriminating between normal corneas and suspect irregular or keratoconic corneas. METHODS: A total of 8526 corneal tomography images of 4904 eyes obtained between November 2010 and July 2017 using a combined Scheimpflug/Placido tomographer were retrospectively evaluated. Each image was evaluated for acquisition quality and was labeled as normal, suspect irregular or keratoconic by a cornea specialist. Two algorithms were built. The first was based on 94 instrument-derived output parameters, and the second integrated keratoconus prediction indices of the device with the 94 instrument-derived output parameters. Both models were compared with the tomographer's keratoconus detection algorithms. Out of the 8526 images evaluated, 7104 images of 3787 eyes had sufficient acquisition quality. Of those, 5904 examinations were randomly chosen for construction of the models using the random forest algorithm. The models were then validated using the remaining 1200 examinations. RESULTS: Both RF algorithms had a larger AUC compared with any of the tomographer's KC detection algorithms (p < 10-9). The first constructed model had 90.2% accuracy, sensitivity of 94.2%, and specificity of 89.6% (Youden 0.838). Calculated AUC was 0.964. The second model had 91.5% accuracy, sensitivity of 94.7%, and specificity of 89.8% (Youden 0.846). Calculated AUC was 0.969. CONCLUSION: Using the RF machine-learning algorithm, accuracy of discrimination between normal, suspect irregular and keratoconic corneas approximates that of an experienced corneal expert. Applying machine learning to corneal tomography can facilitate keratoconus screening in large populations as well as off-site screening of refractive surgery candidates.

Centration of myopic refractive ablation: should we center treatment on the pupil or the visual axis?

The purpose of this study is to compare pupil versus corneal vertex-centered ablation for myopic laser refractive surgery. This study is a retrospective case series of right eyes of consecutive myopic patients undergoing either photorefractive keratectomy (PRK) or laser-assisted in situ keratomileusis (LASIK) with pupil or corneal vertex-centered ablation from January 2018 to April 2018. Overall 258 eyes of 258 patients were included. Of the 104 that underwent LASIK, 52 were treated centered on the corneal vertex (50%), and of the 154 that underwent PRK, 77 were treated centered on the corneal vertex (50%). There were no significant differences in baseline age, gender, spherical equivalence, sphere, cylinder, or angle kappa between both groups in either LASIK or PRK. There were no significant differences between the corneal vertex-centered and pupil-centered groups in terms of efficacy index (LASIK: 1.02 ± 0.14 vs 1.01 ± 0.13, p = 0.86; PRK: 1.00 ± 0.13 vs 0.99 ± 0.15, p = 0.61), safety index (LASIK: 1.02 ± 0.12 vs 1.01 ± 0.13, p = 0.70; PRK:1.02 ± 0.12 vs 1.02 ± 0.09, p = 0.97), and residual astigmatism (LASIK: 0.26 ± 0.25 vs 0.23 ± 0.28, p = 0.65; PRK:0.37 ± 0.41 vs 0.39 ± 0.31, p = 0.78). In mixed effect models, there were no significant differences between the corneal vertex-centered and pupil-centered groups when accounting for angle kappa (p > 0.05). Patients with large angle kappa (> 300 µm) eyes yielded similar results (p > 0.05). For conclusion, in myopic refractive surgery, performing ablation centered on the corneal vertex or on the pupil leads to similar outcomes regardless of the amount of angle kappa.

Predictability of Biometry in Patients Undergoing Cataract Surgery.

PURPOSE: To compare measurements of axial length (AL), anterior chamber depth (ACD), keratometry (K), and the refractive predictability of the Aladdin and IOLMaster biometry devices in cataract surgery patients. METHODS: A retrospective observational study of eyes undergoing cataract surgery. Data were retrieved on AL, ACD, and K measurements obtained by the Aladdin and the IOLMaster. Furthermore, the postoperative refractive prediction errors were compared between the devices. RESULTS: The study included 127 consecutive eyes of 127 patients undergoing cataract surgery. Mean measurements of AL were not significantly different between the Aladdin (24.18 ± 1.89 mm) and IOLMaster (24.18 ± 1.89 mm) (p = 0.792). Mean K measurements were different between Aladdin (43.84 ± 1.56 D) and IOLMaster (43.97 ± 1.61 D) (p < 0.001). For AL, Aladdin measurements correlated strongly with IOLMaster measurements (r = 0.9997). For K, Aladdin measurements correlated strongly with IOLMaster measurements (r = 0.9912). Fifty-eight of the 127 eyes underwent cataract surgery with a monofocal intraocular lens. For these, mean absolute error (MAE) in predicting refraction relative to the measured postoperative refraction differed between Aladdin (MAE = 0.54 ± 0.40D) and IOLMaster (MAE = 0.49 ± 0.41D) (p = 0.001). After adjustment for the systematic difference in K measurements, the difference in MAE was no longer significant (p = 0.601). The ACD measurements did not differ significantly (p = 0.873) and were well correlated (r = 0.8327). CONCLUSIONS: A very good correlation was found in AL, K, and ACD measurements between the Aladdin biometer and the IOLMaster. Minimal adjustment for the constant difference in keratometry measurements matched the refractive predictability of both devices.

Comparison of Ishihara Booklet with Color Vision Smartphone Applications.

PURPOSE: To compare the standard Ishihara booklet with color-vision-testing smartphone applications. METHODS: A prospective observational diagnostic study on 42 normal trichromats and 38 color-deficient subjects. Patients were presented with three color vision tests in random order: an Ishihara test booklet and two color-vision-testing smartphone applications: Eye2Phone and the Color Vision Test application (CVT app). Sensitivity and specificity of the electronic tests was compared with Ishihara results, and in each one of these applications every plate was individually analyzed for success/failure rate. RESULTS: Average age was 42.7 ± 12.9 years. There were 57 males (71.2%). Sensitivity and specificity of each test was 100% (38/38) and 95.2% (40/42) for the Eye2Phone, and 100% (38/38) and 54.8% (23/42) for the CVT app. There was no significant difference between the Ishihara booklet and the Eye2Phone (p = 0.500), with a high kappa measure of agreement (0.950, p < 0.001). The CVT app was significantly different than both other tests (p < 0.001) with a low kappa measure of agreement (0.535 with the Ishihara and 0.575 with the Eye2Phone). Of the 21 tested plates, color-deficient subjects failed 11.8 ± 3.1 plates in the Ishihara booklet and 14.1 ± 2.1 plates in the Eye2Phone (p < 0.001). Significant plate-specific differences for the color-deficient group were found in plate numbers 3, 6, 7, 8, 9, 15, and 16. Both tests were poorly able to give an indication of the specific dichromatism type. The Ishihara booklet was rated more comfortable and clearer than the Eye2Phone in color-deficient subjects. The CVT app was rated lowest for comfort and clarity in both groups. CONCLUSIONS: Smartphone applications testing for color vision deficiency are readily available; however, users of these apps should be aware that some may have different sensitivity for detection of color vision deficiency compared to Ishihara booklet, limiting their usefulness for clinical use. Therefore, further validation of these applications is required.

Evaluation of the retinal, choroidal, and nerve fiber layer thickness changes in patients with toxic anterior segment syndrome.

PURPOSE: To evaluate changes in choroidal, retinal, and nerve fiber layer (NFL) thickness following toxic anterior segment syndrome (TASS). METHODS: Macular and peripapillary choroidal thickness was measured using enhanced depth imaging (EDI) optical coherence tomography (OCT) on the day of the diagnosis and on three follow-up exams (months 1 to 4). A similar OCT analysis of central retinal and NFL thickness was performed. RESULTS: Thirteen TASS patients were included. Average age was 72.8 ± 8.7 years. Macular choroidal thickness in the superior, subfoveal, and nasal macula in the study eye was larger than the control eye and decreased at months 2-4. This was statistically significant only for the superior macula (p = 0.004). Peripapillary choroidal thickness was larger in the study eye at baseline compared with the control eye-significantly so in the nasal (p = 0.026) and inferior (p = 0.033) locations. Peripapillary choroidal thickness peaked at the baseline or 1st month exam and decreased thereafter. Retinal thickness increased significantly with time, peaking at the 2nd month and decreasing thereafter. No changes were found in the NFL. CONCLUSIONS: TASS may have a transient effect on the choroid. Changes in retinal thickness are probably a normal transient postoperative response and not a result of TASS.

CHARACTERISTICS AND LONG-TERM OUTCOME OF PATIENTS WITH NONINFECTIOUS RETINAL VASCULITIS.

PURPOSE: To investigate the characteristics and long-term outcome of patients with noninfectious retinal vasculitis. METHODS: This was a retrospective multicenter study. Main outcome measures included patients' characteristics, ocular findings, treatment modalities, and best-corrected visual acuity. All patients had at least 12-month follow-up time. RESULTS: Eighty-two eyes (45 patients) were included. Median follow-up was 46 months (range, 12-210 months). At presentation, 12 of the 45 patients (26.6%) had a known associated systemic or ocular disease. A diagnosis of a new systemic disease was found in additional 14 of 33 patients (42.5%) and birdshot chorioretinopathy in 3 of 33 patients (9.1%). The most common systemic disease was Behcet disease (17/24 patients; 70.8%). Laboratory tests had a low diagnostic value. The most common clinical findings were vitritis (58.5%) and perivascular sheathing (50.5%). Most patients were treated with immunosuppressive medications. Mean best-corrected visual acuity improved significantly during follow-up, patients with Behcet disease and worse visual acuity at baseline were more likely to have visual acuity improvement (P < 0.001). CONCLUSION: A new systemic or ocular disease associated with retinal vasculitis was found in more than half of the patients. Behcet disease was the most common newly diagnosed disease. Specific diagnosis leading to proper management is important to maintain favorable long-term visual outcome.

Corneal collagen crosslinking: a systematic review.

Keratoconus (KCN) is an ectatic disorder with progressive corneal thinning and a clinical picture of corneal protrusion, progressive irregular astigmatism, corneal fibrosis and visual deterioration. Other ectatic corneal disorders include: post-LASIK ectasia (PLE) and pellucid marginal degeneration (PMD). Corneal crosslinking (CXL) is a procedure whereby riboflavin sensitization with ultraviolet A radiation induces stromal crosslinks. This alters corneal biomechanics, causing an increase in corneal stiffness. In recent years, CXL has been an established treatment for the arrest of KCN, PLE and PMD progression. CXL has also been shown to be effective in the treatment of corneal infections, chemical burns, bullous keratopathy and other forms of corneal edema. This is a current review of CXL - its biomechanical principles, the evolution of CXL protocols in the past, present and future, indications for treatment, treatment efficacy and safety.

Intravitreal dexamethasone implant in patients with persistent macular edema of variable etiologies.

PURPOSE: To examine the effect of an intravitreal dexamethasone drug delivery system (DEX-DDS) in the treatment of persistent cystoid macular edema (CME) of different etiologies. METHODS: Thirty-seven eyes with persistent CME were treated with DEX-DDS and analyzed for changes in best-corrected visual acuity (BCVA) and optical coherence tomography. Eyes were categorized into three groups: diabetic macular edema (DME, n = 14), vein occlusion (n = 15) and uveitis (n = 7). RESULTS: The mean follow-up was 22 ± 6.9 weeks. BCVA improved from 0.62 ± 0.38 to 0.35 ± 0.29 logMAR (p < 0.0001). Central macular thickness decreased by 184 ± 246 µm from baseline (p < 0.0001). In eyes where CME resolved and recurred, the average CME-free period was 11 weeks. The uveitis group showed faster CME resolution (2 weeks) and a longer CME-free period (20 weeks). Similar efficacy was shown for repeat DEX-DDS injections. The safety profile was good. CONCLUSION: DEX-DDS is beneficial in the treatment of persistent CME. In cases of uveitis, CME resolution is rapid, resulting in the longest effect duration, when compared with other CME etiologies.

Long-term outcome of an intravitreal dexamethasone implant for the treatment of noninfectious uveitic macular edema.

PURPOSE: To report the long-term outcome of an intravitreal dexamethasone drug delivery system (DEX-DDS) injection for noninfectious uveitic macular edema. METHODS: This was a retrospective study of 8 eyes (7 patients). RESULTS: The mean follow-up time was 17.3 months. Macular edema resolved in all eyes at 3.9 weeks (range 1-6.9) postinjection. The central point thickness improved from 612 ± 143 to 250 ± 55 µm (p < 0.05). The mean best corrected visual acuity improved by 0.25 logMAR (p < 0.05) at 3.9 weeks (range 1-6.9) postinjection. In 5 eyes, macular edema did not recur after a mean follow-up of 14.5 months. In 3 eyes, macular edema relapsed after 4.7 months (range 3.6-6.3) and resolved again following further injections. Two eyes developed intraocular pressure elevation, which was well controlled with topical treatment. CONCLUSIONS: Intravitreal DEX-DDS injections resulted in resolution of macular edema and visual acuity improvement. Some eyes required repeated injections, but most eyes achieved long-term resolution. No significant complications were noticed.

Factors Predicting Loss of Best-Corrected Visual Acuity After Hyperopic Laser-Assisted In Situ Keratomileusis.

PURPOSE: The aim of this study was to identify risk factors for the loss of corrected distance visual acuity (CDVA) after uncomplicated hyperopic laser-assisted in situ keratomileusis (LASIK). METHODS: A retrospective study including hyperopic patients who underwent microkeratome-assisted LASIK between January 2000 and December 2019 at Care-Vision Laser Centers, Tel-Aviv, Israel. Loss of CDVA was defined as ≥ 2 lines (0.20 logarithm of the minimum angle of resolution [logMAR] increase). Excluded were patients who had loss of CDVA because of intraoperative or postoperative complications or developed cataract at their final visit. RESULTS: Overall, 1998 eyes of 1998 patients were included in the study, of which 35 eyes (1.75%) had CDVA loss at final follow-up (mean 387 days). The vision-loss group had a significantly greater spherical treatment (3.4 vs. 2.8 D, P = 0.02), ablation depth (69.4 vs. 53.8 µm, P = 0.01), a higher proportion of treatments with a smaller optic zone (6.0 mm) (31.4% vs. 13.4%, P = 0.002), treatment with the EX200 (Alcon) excimer rather than the EX500 (Alcon) (74.3% vs. 39.0%, P < 0.001), and treatment with the Moria M2-90 microkeratome rather than the Moria Sub-Bowman's keratomileusis (SBK) microkeratome (65.7% vs. 29.6%, P < 0.001). In multivariate binary logistic regression, factors that remained significant predictors of CDVA loss were a greater spherical treatment (per 1 D treatment, odds ratio = 1.42, 95% CI, 1.11-1.81, P = 0.004) and the use of the Moria M2-90 microkeratome (odds ratio = 4.66, 95% CI, 2.30-9.45, P < 0.001). CONCLUSIONS: In patients undergoing uncomplicated hyperopic LASIK, a greater spherical hyperopic treatment is associated with a higher risk for vision loss. Transition to a newer microkeratome model significantly reduced vision loss rate.

Factors Predicting Slow Visual Recovery Following Hyperopic LASIK.

PURPOSE: To identify factors predicting slow visual recovery following hyperopic laser in situ keratomileusis (LASIK). METHODS: The study included consecutive patients who underwent hyperopic LASIK between January 2005 and December 2019 at a single medical center. Patients were divided into two groups according to whether they experienced normal recovery of visual acuity (1-week visit) or slow visual recovery (1-month visit). Visual recovery was defined as achieving an efficacy index of 0.9 or greater. Efficacy index was calculated as postoperative uncorrected distance visual acuity / preoperative corrected distance visual acuity. A comparison of baseline and intraoperative parameters was performed. Binary logistic regression was performed to identify potential predictors of slow visual recovery. RESULTS: Overall, 861 eyes of 861 patients were included. Mean age was 48.0 ± 9.5 years and 55.9% were women. Two hundred forty-nine patients (28.9%) experienced slow visual recovery. Younger age (P = .01), a larger preoperative spherical equivalence (P = .002), and greater maximum ablation depth (P = .002) were predictors of slow visual recovery. In binary logistic regression, female gender (P = .036) and greater spherical equivalence (P = .007) remained significant predictors of slow visual recovery. CONCLUSIONS: Female gender and greater preoperative spherical equivalence were associated with slow visual recovery. Patients may be advised accordingly. [J Refract Surg. 2024;40(1):e42-e47.].

Factors Predicting Slow Visual Recovery Following Hyperopic LASIK.

PURPOSE: To identify factors predicting slow visual recovery following hyperopic laser in situ keratomileusis (LASIK). METHODS: The study included consecutive patients who underwent hyperopic LASIK between January 2005 and December 2019 at a single medical center. Patients were divided into two groups according to whether they experienced normal recovery of visual acuity (1-week visit) or slow visual recovery (1-month visit). Visual recovery was defined as achieving an efficacy index of 0.9 or greater. Efficacy index was calculated as postoperative uncorrected distance visual acuity / preoperative corrected distance visual acuity. A comparison of baseline and intraoperative parameters was performed. Binary logistic regression was performed to identify potential predictors of slow visual recovery. RESULTS: Overall, 861 eyes of 861 patients were included. Mean age was 48.0 ± 9.5 years and 55.9% were women. Two hundred forty-nine patients (28.9%) experienced slow visual recovery. Younger age (P = .01), a larger preoperative spherical equivalence (P = .002), and greater maximum ablation depth (P = .002) were predictors of slow visual recovery. In binary logistic regression, female gender (P = .036) and greater spherical equivalence (P = .007) remained significant predictors of slow visual recovery. CONCLUSIONS: Female gender and greater preoperative spherical equivalence were associated with slow visual recovery. Patients may be advised accordingly. [J Refract Surg. 2024;40(1):e42-e47.].

Factors Predicting the Need for Re-treatment After Laser Refractive Surgery in Patients With Mixed Astigmatism.

PURPOSE: To identify risk factors that increase the likelihood of re-treatment following refractive surgery in patients with mixed astigmatism. METHODS: This was a retrospective study including patients who underwent either laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) between 2000 and 2019 and had mixed astigmatism (spherical error of +0.50 D or greater and spherical equivalent of less than 0.00 diopters [D]). Patients were divided into two groups according to whether they underwent re-treatments during the study period. RESULTS: Overall, 785 eyes (785 patients) were included. In total, 5.2% of the eyes (n = 41) underwent re-treatment. The re-treatment group was more likely to have preoperative high astigmatism (80.5% vs 48.3%, P < .001), moderate to high hyperopia (36.6% vs 22.3%, P = .035), and to have undergone surgery earlier during the study period (P < .001). They were also more likely to have undergone surgery using the Wave-Light EX200 rather than the EX500 laser platform (Alcon Laboratories, Inc) (P < .001), have a treated optical zone of 6 mm rather than 6.5 mm (P < .001 for both), and their maximum ablation depth was greater (P < .001). There was no difference between the re-treatment and control groups regarding procedure type (PRK vs LASIK). Binary logistic regression found preoperative high astigmatism (odds ratio = 3.97, P < .001) and the type of laser platform used (EX200, odds ratio = 7.78, P < .001) as the only independent factors associated with re-treatment. CONCLUSIONS: Re-treatment rates following correction of mixed astigmatism were 5.2% over 20 years. Use of a sixth-generation laser platform significantly reduced the risk of re-treatment. Presence of high astigmatism is a significant risk factor for re-treatment. There was no difference in retreatment risk between PRK and LASIK. [J Refract Surg. 2024;40(2):e73-e78.].

Hyperopic LASIK and postoperative corneal steepness: revisiting the 49-diopter limit.

PURPOSE: To compare corrected distance visual acuity (CDVA) outcomes of hyperopic laser in situ keratomileusis (LASIK) with a postoperative corneal steepness above vs below 49 diopters (D). SETTING: Care-Vision Laser Centers, Tel-Aviv, Israel. DESIGN: Retrospective study. METHODS: This study included consecutive patients who underwent hyperopic LASIK between January 2013 and December 2019. Hyperopic patients were divided into 2 groups based on postoperative corneal steepness with steep corneas defined >49.0 D and the control group ≤49.0 D. Adjustments were performed to account for differences in baseline and intraoperative parameters. RESULTS: Overall, 1703 eyes of 1703 patients were included. Mean age was 48.3 ± 10.0 years, and 45.3% were male. Preoperatively, the steep group (2.4%, n = 41/1703) had steeper mean (44.6 D vs 43.1 D, P < .001) and steep (45.1 D vs 43.5 D, P < .001) keratometry, worse logMAR CDVA (0.07 vs 0.04, P = .02), and higher sphere (4.9 D vs 2.9 D, P < .001). Intraoperatively, they had a higher spherical treatment (4.6 D vs 2.8 D, P < .001). After hyperopic LASIK, the steep group had worse logMAR CDVA (0.10 vs 0.06, P = .01). However, after accounting for differences in baseline and spherical treatment, no significant differences were found in postoperative logMAR CDVA (0.06 vs 0.06, P = .99). The factors that remained associated with worse postoperative CDVA were higher spherical treatment (0.01 logMAR per 1 D, P < .001) and preoperative CDVA (0.60 logMAR per 1.00 logMAR, P < .001). CONCLUSIONS: Postoperative corneal steepness greater than 49 D is not associated with worse visual outcomes after hyperopic LASIK. However, lower preoperative visual potential and higher spherical treatment applied are associated with worse outcomes. The 49 D cutoff should be revisited.

Comparison of Intraocular Lens Power Prediction Accuracy Between 2 Swept-Source Optical Coherence Tomography Biometry Devices.

PURPOSE: To compare intraocular lens (IOL) power prediction accuracy of the Eyestar 900 (EyeS900) and the IOLMaster 700 (IOLM700) based on estimated and measured posterior corneal power. DESIGN: Retrospective, interinstrument reliability study. METHODS: Setting: Institutional. PARTICIPANTS: Two hundred twenty-five eyes of 225 cataract surgery patients. MEASUREMENTS: Patients underwent measurements by both devices preoperatively. MAIN OUTCOME MEASURES: Spherical Equivalent Prediction Error (SEQ-PE), spread of the SEQ-PE (precision) and the absolute SEQ-PE (accuracy) of each device using Barrett Universal II (BUII) formula with either estimated posterior keratometry (E-PK) or measured posterior keratometry (M-PK). RESULTS: Trimmed mean SEQ-PEs of EyeS900 E-PK, EyeS900 M-PK, IOLM700 E-PK, and IOLM700 M-PK were 0.03, 0.08, 0.02, and 0.09 D, respectively with no significant differences between EyeS900 E-PK and IOLM700 E-PK (P = 0.31) as well as between EyeS900 M-PK and IOLM700 M-PK (P = 0.31). Statistically significant SEQ-PE differences were found when E-PK and M-PK were compared, regardless of the device used, showing hyperopic SEQ-PE in M-PK calculations. Excellent correlation and agreement in SEQ-PE were found between the devices for both E-PK (P < 0.001, r = 0.848, mean bias: +0.01 D, 95% LOA of -0.32 to +0.34 D) and M-PK (P < 0.001, r = 0.776, mean bias: -0.01 D, 95% LOA of -0.42 to +0.39 D). No significant differences were found comparing absolute SEQ-PE and precision of the devices. CONCLUSION: The Eyestar 900 and the IOLMaster 700 show comparable IOL power prediction accuracy by the BUII formula using either estimated or measured posterior keratometry. An adjusted lens factor may be required for BUII when utilizing measured posterior keratometry in both devices.

Analysis of the ESCRS Calculator's Prediction Accuracy.

PURPOSE: To evaluate prediction accuracy of formulas included in the ESCRS-Online-IOL-Calculator using standard keratometry (K) or total keratometry (TK). SETTING: Hospital-based academic practice. DESIGN: Retrospective case-series. METHODS: Participants: 523 cataract patients (523 eyes). Outcome Measures: trimmed-means of the spherical equivalent prediction error (SEQ-PE, trueness), precision and absolute SEQ-PE (accuracy) of all seven formulas available on the ESCRS-Online-IOL-Calculator as well as the mean (Mean-All) and median (Median-All) of the predicted SEQ refraction of all formulas. Sub-group analyses evaluated the effect of axial length on formula accuracy. RESULTS: Trimmed-mean SEQ-PE range of all formulas varied from -0.075 to +0.071D for K-based and from -0.003 to +0.147D for TK-based calculations, with TK-based being more hyperopic in all formulas (p<0.001). Precision ranged from 0.210 to 0.244D for both K-based and TK-based calculations. Absolute SEQ-PE ranged from 0.211 to 0.239D for K-based and from 0.218 to 0.255D for TK-based calculations. All formulas, including Mean-All and Median-All, showed high accuracy with 84-90% of eyes having SEQ-PEs within 0.50D.Myopic trimmed-mean SEQ-PEs significantly different from zero were observed in long eyes for Pearl DGS (-0.110D, p=0.005), Hill RBF (-0.120D, p<0.001) and Hoffer QST (-0.143D, p=0.001), and in short eyes for EVO 2.0 (-0.252D, p=0.001), Kane (-0.264D, p=0.001), Hoffer QST (-0.302D, p<0.001), Mean-All (-0.122D, p=0.038) and Median-All (-0.125D, p=0.043). CONCLUSION: Prediction accuracy of all ESCRS IOL Calculator formulas was high and globally comparable. TK-based calculations did not increase prediction accuracy and tended towards hyperopia. Observations indicating formula superiority in long and short eyes merit further evaluation.

Comparison of biometry measurements and intraocular lens power prediction between 2 SS-OCT-based biometers.

PURPOSE: To evaluate the agreement in biometry measurements and intraocular lens (IOL) power prediction between the Eyestar 900 and the IOLMaster 700. SETTING: Institutional. DESIGN: Retrospective comparative study. METHODS: Patients were evaluated before cataract surgery using both devices on the same visit. Axial length, anterior and posterior keratometry, anterior chamber depth, corneal diameter (CD), central corneal thickness, and lens thickness were recorded by both devices. The agreement in measurements and in IOL power calculations was evaluated using the Barrett Universal II (BU-II) formula with either predicted or measured posterior keratometry. RESULTS: In total, 402 eyes of 402 consecutive patients were included. The mean age was 72.0 ± 9.2 years. Clinically, mean differences in measured variables were small, albeit slightly larger for posterior flat and steep keratometry (0.43 diopters [D] and 0.42 D, respectively). The measurement correlation and agreement between the devices were good for all variables with slightly lower agreement in CD measurements. Consistent bias was seen in measurements of posterior flat and steep keratometry. Good agreement was also found in anterior and posterior astigmatism measurements. Good IOL power calculation agreement was found using either predicted posterior keratometry (95% limits of agreement [LoA] of -0.40 to +0.30 D) or measured posterior keratometry (95% LoA of -0.45 to +0.40 D). The agreement was within ±0.5 D in 394 eyes (98.0%) using predicted posterior keratometry and in 386 eyes (96.0%) using measured posterior keratometry. CONCLUSIONS: The Eyestar 900 and the IOLMaster 700 show strong agreement in biometry measurements and IOL power prediction by the BU-II formula using either standard or total corneal keratometry and can be used interchangeably.

Use of a Novel Three-dimensional Head-mounted Digital Visualization Platform in Corneal Endothelial Transplantation.

INTRODUCTION: To report the first endothelial keratoplasty procedures performed using a 3D digital head-mounted ophthalmic exoscope. METHODS: Three patients underwent Descemet stripping automated endothelial keratoplasty (DSAEK) using a 3D digital ophthalmic exoscope (Beyeonics One, Beyeonics Vision, Haifa, Israel) at the Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. RESULTS: All procedures were uneventful, leading to resolution of corneal edema and vision improvement. Surgeons reported excellent visualization and minimal lag, almost negligible, with the benefits of improved ergonomics and the use of head gestures to control zoom, focus, brightness, and panning. There were no postoperative complications. CONCLUSION: The new 3D digital ophthalmic exoscope system can be successfully used in DSAEK surgery with potential advantages in ergonomics, picture quality, and image control. Further studies can compare this system with either standard operating microscopes or 3D heads-up display systems.

Five-Year Safety and Efficacy of Femtosecond Laser-Assisted Descemet Membrane Endothelial Keratoplasty.

PURPOSE: The purpose of this study was to evaluate 5-year safety and efficacy outcomes of femtosecond-enabled Descemet membrane endothelial keratoplasty (F-DMEK) in patients with Fuchs' endothelial dystrophy (FED). METHODS: This was a retrospective study, including patients with FED and cataract who underwent either F-DMEK (16 eyes of 15 patients) or manual DMEK (M-DMEK) (42 eyes of 37 patients) combined with cataract extraction. Outcome measures included visual acuity, graft detachment, graft survival, and endothelial cell loss. RESULTS: The average follow-up in F-DMEK and M-DMEK was 57.1 ± 12.4 months and 58.5 ± 17.3 months, respectively ( P = 0.757). The rates of primary failure (0% vs. 9.5%, P = 0.567), secondary failure (0% for both), and graft rejection (0% vs. 7.1%, P = 0.533) did not differ significantly between the groups. Improvement in best spectacle-corrected visual acuity was similar in F-DMEK and M-DMEK (0.32 ± 0.27 logarithm of the minimum angle of resolution and 0.35 ± 0.44 logarithm of the minimum angle of resolution, respectively, P = 0.165) and persisted at 2, 3, 4, and 5 years and at the last follow-up. The rates of graft detachment and rebubbling were significantly lower with 6.25% in F-DMEK and 33.3% in M-DMEK ( P = 0.035). Cell-loss rates were lower in F-DMEK compared with M-DMEK throughout the follow-up, significantly so up to 2 years with a difference of 8.6% at 1 year ( P = 0.023), 11.8% at 2 years ( P = 0.021), 7.6% at 3 years ( P = 0.088), 5.8% at 4 years ( P = 0.256), 13.6% at 5 years ( P = 0.169), and 7.1% at the final follow-up ( P = 0.341). CONCLUSIONS: F-DMEK had an excellent safety and efficacy profile which was maintained over 5 years of follow-up. Lower endothelial cell-loss rates in F-DMEK compared with M-DMEK may help extend the duration of graft survival.