Accuracy of Toric Intraocular Lens Calculators with Predicted and Measured Posterior Corneal Astigmatism Across Different Types of Astigmatism.

INTRODUCTION: This study is a retrospective case series to compare the accuracy of the Barrett toric calculator using predicted posterior corneal astigmatism (PCA) and PCA measurements using swept-source optical coherence tomography (SS-OCT) and a Scheimpflug camera. This evaluation was conducted across different types of anterior and posterior astigmatism. METHODS: A total of 146 eyes from 146 patients implanted with toric intraocular lenses were included. Mean absolute prediction error, standard deviation of prediction error, and the percentage of eyes with prediction errors within ±0.50 diopters (D) were calculated using vector analysis. Biometric measurements were conducted using the IOLMaster 700 and Pentacam HR. A subgroup analysis was conducted based on the orientation of both anterior and posterior corneal astigmatism. RESULTS: The Barrett toric calculator with predicted PCA yielded the best results, with 78.1% having a prediction error ≤ 0.50 D, which was a significantly higher percentage than the Barrett formula with the two versions of measured PCA (P < 0.05). In the subgroup with a horizontally steep meridian PCA using the IOLMaster 700, the Barrett formula with predicted PCA yielded the best results, with 78.3% of cases having a prediction error of less than 0.5 D. This percentage was significantly higher than the other two measured PCA subgroups (P < 0.05). CONCLUSION: The Barrett toric formula with predicted PCA demonstrated a statistically significantly higher proportion of cases with a prediction error ≤ 0.5 D compared to the two measured PCA formulas (from the IOLMaster 700 or Pentacam). This trend persisted even when the posterior corneal astigmatism was horizontally steep.

In Vivo Human Lacrimal Gland Imaging Using an Ultrasound Biomicroscopy.

Purpose: In the present study, we introduce human lacrimal gland imaging using an ultrasound biomicroscopy (UBM) with a soft cover and show their findings. Methods: The representative UBM findings of palpebral lobes in seven subjects (4 with non-Sjögren dry eye syndrome, 1 with Sjögren syndrome, and 2 healthy subjects) were described in this study. To prolapse the palpebral lobe, the examiner pulled the temporal part of the upper eyelid in the superotemporal direction and directed the subject to look in the inferonasal direction. We scanned the palpebral lobes longitudinally and transversely using UBM. We used an Aviso UBM (Quantel Medical, Clermont-Ferrand, France) with a 50 MHz linear probe and ClearScan. Results: In UBM of two healthy subjects, the echogenicity of the lacrimal gland was lower than that of the sclera and homogeneous. But, the parenchyma of a patient with Sjögren dry eye syndrome was quite inhomogeneous compared to the healthy subjects. In two patients with dry eye syndrome, we were able to observe some lobules in the parenchyma. We could find excretory ducts running parallel at the surface of the longitudinal section in some subjects. In the longitudinal UBM scan of a subject, we observed a tubular structure at a depth of 1500 µm that was considered a blood vessel. It ran from the superonasal to the inferotemporal direction. In a subject, we observed a large cyst beneath the conjunctiva. Conclusions: Lacrimal gland imaging using UBM has both advantages of OCT and sonography, and could be useful for evaluating dry eye syndrome.

Ocular parameters associated with visual performance of enhanced monofocal intraocular lens.

BACKGROUND: An enhanced monofocal intraocular lenses (IOLs) (Tecnis Eyhance ICB00 and Tecnis Eyhance Toric DIU) has been developed to enhance intermediate vision while avoiding the disadvantages of multifocal IOLs. Although many studies have demonstrated the improvement of intermediate visual acuity with enhanced monofocal IOLs, it is not known specifically for which patients these IOLs should be recommended or avoided. In this study, we aim to find out which ocular parameters affect vision performance and photic phenomenon of ICB00 or DIU at different distances. METHODS: Patients who underwent cataract surgery with ICB00 or DIU, performed by a single surgeon, were included. Before surgery, the patients' age, gender, axial length, anterior chamber depth, spherical aberration Z (4,0), vertical coma, horizontal coma, angle kappa (κ), angle alpha (α), and other ocular parameters were investigated. One month after surgery, uncorrected near visual acuity (UNVA at 40 cm), uncorrected intermediate visual acuity (UIVA at 66 cm), uncorrected distance logMAR visual acuity (UDVA), IOL decentration, and quality of vision (QoV) questionnaires were conducted. RESULTS: A total of 43 patients (58 eyes) were included. The results of the univariate linear regression analyses showed a negative correlation between spherical aberration and logMAR UNVA and UIVA (p = 0.003, ß=-0.51 and p = 0.018, ß=-0.23, respectively) and a positive correlation between angle α and logMAR UIVA (p = 0.036, ß = 0.19). Deeper anterior chamber depth (ACD) was associated with poorer total QoV (p = 0.018, ß = 14.43), particularly in glare, halo, blur, and fluctuation perception. A higher degree of IOL decentration tended to decrease UNVA and UIVA (Pearson correlation coefficient, r = 0.336 and r = 0.221, respectively); however, no significant effect was observed on UDVA (Pearson correlation coefficient, r = 0.042). CONCLUSIONS: In enhanced monofocal IOLs, a higher level of spherical aberration is associated with better performance in UNVA and UIVA, whereas a larger angle α has a negative impact. A deeper ACD negatively affects the QoV.

Retrospective Analysis of a New Intrastromal Dissection Technique Using the Retinal Reflex for Deep Anterior Lamellar Keratoplasty.

PURPOSE: The purpose of this study was to describe a new surgical technique for deep anterior lamellar keratoplasty. METHODS: All pupils in the recipient eyes were dilated preoperatively. Vertical grooving was performed using a crescent blade with a width of 5 mm and a depth of one-third to half corneal thickness on the temporal side of the limbus. Stromal dissection was performed as close as possible to Descemet membrane by observing the gap between the gold line by retinal reflex and the front edge of the crescent blade. Lamellar dissection was performed along the lamellar plane using corneal dissectors. The ophthalmic viscoelastic device was injected into the intrastromal pocket to separate the anterior and posterior stroma and an anterior corneal lamella was excised. A donor cornea was sutured into the recipient bed. RESULTS: In 18 eyes, none of the patients had Descemet membrane rupture during surgery. The mean postoperative residual stromal thickness was 80 ± 31 µm. The mean central corneal thickness after surgery was 660 ± 69 µm. At the last follow-up, the cornea was cleared in all 18 eyes on slit-lamp examination. CONCLUSIONS: We estimated the residual stromal thickness based on the gap between the gold line by the retinal reflex and crescent blade, and intrastromal lamellar dissection was performed using a smooth corneal dissector. Consequently, the surface of stromal dissection was smooth, and the residual stromal thickness was even.

Categorization of Meibomian Gland Dysfunction Using Lipid Layer Thickness and Meibomian Gland Dropout in Dry Eye Patients: A Retrospective Study.

PURPOSE: In the present study, we determined the prevalence of obstructive meibomian gland dysfunction (MGD), hyposecretory MGD, grossly normal MG, and hypersecretory MGD in patients with dry eye syndrome using lipid layer thickness (LLT) and MG dropout. METHODS: Eighty-eight patients with dry eye syndrome were included in the study. Patients were categorized into four groups according to the LLT and weighted total meiboscore. The proportion of patients in each group was calculated. The age, sex, Ocular Surface Disease Index, LLT, Schirmer, tear film breakup time, cornea stain, weighted total meiboscore, expressibility, and quality of meibum were compared between the four groups. RESULTS: Fifteen eyes (17.0%) had obstructive MGD, two eyes (2.3%) had hyposecretory MGD, 40 eyes (45.5%) had grossly normal MG, and 17 eyes (19.3%) had hypersecretory MGD. The obstructive MGD group was younger than the grossly normal MG group. In obstructive MGD, the ratio of men to women was higher than that of the other groups. However, Ocular Surface Disease Index, Schirmer, tear film breakup time, and corneal stain did not show statistically significant differences between the four groups. The meibum expressibility of the hyposecretoy MGD group was worse than those of the other groups. The meibum expressibility of the hyposecretoy MGD group was poor than those of the obstructive and hypersecretory MGD group. CONCLUSIONS: This categorization was expected to help determine the best treatment method for dry eye syndrome, according to the MG status.

Comparison of Automated Keratometer and Scheimpflug Tomography for Predicting Refractive Astigmatism in Pseudophakic Eyes.

PURPOSE: To analyse the correspondence between refractive astigmatism and corneal astigmatism in pseudophakic eyes with non-toric intraocular lenses. SETTING: Yeouido St. Mary hospital, Seoul, Republic of Korea. DESIGN: Evaluation of a diagnostic test instrument. METHODS: This retrospective study included 95 eyes of 95 patients. Corneal astigmatism was measured with an automated keratometer (RK-5, Canon) and Scheimpflug tomography (Pentacam HR, Oculus). Refractive astigmatism was compared to keratometric astigmatism (based on anterior corneal measurements only), equivalent K-reading, and total corneal astigmatism (both based on anterior and posterior corneal measurements). Vector analysis was carried out by Næser's polar value method. The accuracy was defined as the average magnitude of the vectorial difference in astigmatism (DA). Each corneal measurement was optimized in retrospect by a multiple linear regression equation between refractive and corneal astigmatism. RESULTS: Keratometric astigmatism overestimated with-the-rule (WTR) refractive astigmatism and underestimated against-the-rule (ATR) refractive astigmatism. Several measurements based on both corneal surfaces' values did not show any statistically significant difference with respect to refractive astigmatism. The mean corneal astigmatism by total corneal refractive power (TCRP) at 4.0 mm (zone/pupil) produced the lowest mean arithmetic DA and the highest percentage of eyes with a DA ≤ 0.50 dioptre. After optimization, the accuracies of automated KA and TCRP 4.0 mm (zone/pupil) were similar. CONCLUSIONS: Total corneal astigmatism measured by Scheimpflug tomography at a 4.0 mm zone centered on the pupil accurately reflects the refractive astigmatism in pseudophakic eyes. However, the accuracy of total corneal astigmatism is not different from automated KA after optimization.

Comparison of Accuracy of Six Modern Intraocular Lens Power Calculation Formulas.

PURPOSE: To compare the accuracy of modern intraocular lens (IOL) power calculation formulas in predicting refractive outcomes after standard cataract surgery. METHODS: The medical records of 203 eyes from 203 patients that received phacoemulsification and IOL implantation were retrospectively reviewed. Partial coherence interferometry was used to obtain the biometric values. The refractive outcomes of Barrett Universal II (BUII), Emmetropia Verifying Optical (EVO) 2.0, Hill-RBF 3.0, Hoffer QST, Kane, and PEARL-DGS formulas were evaluated. Axial length (AL) subgroup analysis was done separately. The correlations between the prediction error calculated by each formula and AL and corneal power were also analyzed. RESULTS: Overall, there was no significant difference between the absolute prediction errors predicted by the six formulas after adjusting the mean prediction error (p = 0.058). AL subgroup analysis of absolute error also showed that there is no significant difference between the formulas. The BUII and Hill-RBF 3.0 formulas showed a higher percentage of eyes with prediction error within ±0.50 diopters compared to the Hoffer QST formula (p = 0.022 and p = 0.035, respectively). However, there was no significant difference after Bonferroni correction was applied. The BUII formula showed the highest IOL Formula Performance Index and therefore the highest accuracy, followed by PEARL-DGS, EVO 2.0, Kane, Hill-RBF 3.0, and Hoffer QST formulas. Out of the six formulas, the prediction error calculated by the Hoffer QST was significantly correlated with the AL (p = 0.011). None of the prediction errors calculated by the six formulas showed correlation to the corneal power. CONCLUSIONS: Analysis of the prediction error showed that the six modern IOL power calculation formulas have comparable accuracy overall and across different ranges of AL.

Comparative Analysis of Optical Quality of Monofocal, Enhanced Monofocal, Multifocal, and Extended Depth of Focus Intraocular Lenses: A Mobile Model Eye Study.

Purpose: To use the revised model eye to observe and compare how the world is perceived by patients with monofocal intraocular lens (IOL), Eyhance, bifocal IOL, and Symfony, and check its performance. Methods: The new mobile model eye consists of an artificial cornea, an IOL, a wet cell, an adjustable lens tube, a lens tube, an objective lens, a tube lens, and a digital single-lens reflex camera. We collected photographs of distant buildings and streets at night, videos of the focusing process, and videos of United States Air Force resolution target from 6 m to 15 cm and analyzed them quantitatively. Results: In this revised model eye using an objective lens, an artificial cornea similar to the human cornea could be used. Using a digital single-lens reflex camera, high-resolution imaging was possible without an additional computer. Fine focusing was possible using an adjustable lens tube. For monofocal IOL, the contrast modulation was 0.39 at 6 m and decreased consistently. It was nearly 0 as the model eye got closer than 1.6 m. For Eyhance, the contrast modulation was 0.40 at 6 m. It then decreased and increased again. At 1.3 m, it was 0.07 and then decreased again. For Symfony, the contrast modulation was 0.18 at 6 m. Symfony showed the characteristics of a bifocal IOL with low add diopter. Halos (234 pixels) were observed around lights, although smaller than those seen with bifocal IOL (432 pixels). Conclusions: We could objectively observe and compare how patients with monofocal IOL, Eyhance, bifocal IOL, and Symfony perceived the world using this revised model eye. Translational Relevance: Data obtained by this new mobile model eye can be used to help patients select their IOLs before cataract surgeries.

Clinical outcomes of a new four-haptic hydrophobic presbyopia-correcting intraocular lens.

A new presbyopia-correcting intraocular lens (IOL) combining bifocal and extended-depth-of-focus profiles (Symbiose: Artis Symbiose Plus; Cristalens Industrie, Lannion, France) was introduced. We compared the output with that of a standard monofocal IOL (PL E: Artis PL E). The two four-haptic hydrophobic IOLs were made of the same material from the same company. Cataract patients bilaterally implanted with either PL E or Symbiose between November 2021 and August 2022 were reviewed. The principal measures of the postoperative results were uncorrected distance visual acuity (UDVA); corrected distance VA (CDVA); uncorrected intermediate VA; uncorrected near VA; objective optical quality; and distance-corrected defocus curves. This study included forty-eight patients (96 eyes), with 22 and 26 patients (44 and 52 eyes, respectively) being implanted with PL E and Symbiose, respectively. All patients received the same type of IOL implanted in both eyes. The average age of patients was 70.9 ± 7.1 and 60.0 ± 8.5 years in PL E and Symbiose groups, respectively, with significantly younger patients in Symbiose group (p < 0.001). Both IOLs displayed excellent UDVA and CDVA with no statistical difference (p = 0.081 (monocular UDVA), p = 0.599 (monocular CDVA), p = 0.204 (binocular UDVA), and p = 0.145 (binocular CDVA)). In comparison with PL E group, Symbiose group showed significantly superior postoperative intermediate and near VA (p < 0.001). PL E group showed significantly superior objective optical quality compared with Symbiose group (p < 0.001). Symbiose provides a continuous range of vision that ensures a seamless transition from far to near with no discontinuity. It also delivers a smooth defocus curve with a larger landing area than the PL E. But the objective optical quality was better in PL E.

Intense pulsed-light treatment improves objective optical quality in patients with meibomian gland dysfunction.

BACKGROUND: To evaluate changes in objective optical quality following intense pulsed light (IPL) treatment combined with meibomian gland (MG) expression (MGX) in patients with MG dysfunction (MGD). METHODS: This retrospective cross-sectional study included MGD-related dry eye disease (DED) patients who received IPL treatment between March and December 2021 at Kim's Eye Hospital, Seoul, Republic of Korea. Each patient underwent four sessions of IPL treatment using Lumenis M22 (Lumenis Ltd., Yokneam, Israel) and MGX at three-week intervals. RESULTS: This study included 90 eyes from 45 patients with MGD. The mean age was 52.3 ± 16.1 years (range, 20-75 years), and 53.3% (24/45) of patients were female. Compared with the baseline, all clinical symptoms and signs significantly improved after IPL treatment combined with MGX. All optical quality parameters obtained with an optical quality analysis system (OQAS: Visiometrics, Castelldefels, Spain) have improved significantly over the baseline (p < 0.001). CONCLUSIONS: In patients with MGD, IPL treatment combined with MGX improved the objective optical quality and clinical signs and symptoms of DED.

Yearly trends in the incidence of ocular traumas and the effects of COVID-19 pandemic: a nationwide population-based study of Korean data.

Background: Ocular trauma can cause irreversible visual impairment, and its incidence is higher than that of other ocular diseases in young patients. Past studies on ocular trauma have been limited in terms of small sample sizes, specific age groups, or a short period of assessment. Moreover, no studies have yet investigated the effects of changes in lifestyle during the coronavirus disease 2019 (COVID-19) pandemic on these trends. Therefore, we aimed to determine the yearly trends in the incidence of various ocular traumas over a 10-year period (2011-2020), and to evaluate the effects of the COVID-19 pandemic on these trends. Methods: In this nationwide, population-based, cross-sectional study, we recorded the yearly number of patients diagnosed with hyphema and those who underwent open reduction surgery for orbital blowout fracture (BOF), primary closure of the cornea or sclera (PCCS), and intraocular foreign body (IOFB) removal. Results: While the annual incidence of closed-globe injuries and PCCS decreased significantly in age groups less than 60 years over the past 10 years, the incidence of surgery for BOF and IOFB increased significantly in age groups greater than or equal to 60 years during the same period. When the 2020 data were compared with data from 2011-2019, hyphema showed the largest decrease (47.24%) in incidence among all ocular traumas, reaching significance in those ages less than 20 years (64.41%, P=0.004); the incidence of surgery for BOF also showed the largest decrease, in patients age less than 20 years. In the population age greater than or equal to 60 years, higher incidences of surgery for BOF and IOFB were observed (13.08% and 25.53%, respectively). Conclusions: While the incidence of closed-globe injuries has decreased over the past 10 years in age groups less than 60 years, those age with more than 60 years have become more prone to serious ocular trauma. During the COVID-19 era, the incidence of closed-globe injuries fell markedly in patients younger than 20 years of the age, possibly due to social distancing which involved school closures and reduction in outdoor activities.

Effect of pre-fragmentation on efficacy and safety for phacoemulsification in femtosecond laser-assisted cataract surgery: a non-randomized clinical trial.

Background: Ultrasound energy during phacoemulsification results in the endothelial cell loss of cornea. Crystallin lens fragmentation with softening before phacoemulsification can be used with femtosecond laser-assisted cataract surgery (FLACS) device. Methods: This non-randomized clinical trial included patients who underwent cataract surgery and not had corneal opacity. Patients who were not possible to apply the interface on the ocular surface, were excluded. Each subject was allowed to decide the surgical method by himself/herself. Cataract surgery was performed with FLACS (groups I and II) or conventional surgical technique (group III). The FLACS group was further subdivided into two groups according to whether a lens softening procedure was performed (group I) or not (group II). The nuclear density of cataract was objectively classified by Pentacam nuclear staging (PNS), preoperatively. Surgical parameters including total phacoemulsification time (TPT), cumulative dissipated energy (CDE), and the balanced salt solution (BSS) volume consumed, were measured during the surgery. Postoperative visual outcomes were evaluated at three months after the surgery, and corneal endothelial cell count (ECC) loss were calculated based on ECC measured before the surgery and two months after the surgery. Results: Eighty-nine eyes from 89 patients were enrolled. Fifty-three were treated using FLACS (groups I; quadrant pattern with softening of pre-fragmentation, n=31 and II; sextant pattern without softening of pre-fragmentation, n=22) and 36 (group III) with the conventional manual technique. The FLACS groups (groups I and II) had statistically significant lower TPT (P<0.001), CDE (P<0.001), and BSS volumes (P<0.001) used in the nucleus removal step compared to group III. Furthermore, ECC loss in groups I (4.59%±2.57%) and II (6.10%±3.30%) were also statistically lower compared to group III (13.49%±10.55%, P<0.001). From subgroup analysis with the PNS 2, group I showed lower pre-fragmentation time, lower CDE, lower BSS volume used during nucleus removal, and lower ECC loss compared to group II (all P<0.001). Conclusions: Pre-fragmentation using FLACS may reduce intraoperative ultrasound energy and intraocular manipulations compared to conventional cataract surgery.

Quantitative analysis of cornea endothelial cell damage from enucleation, corneal buttoning, and storage in donor corneas using trypan blue dye staining.

We aimed to quantitatively analyze the corneal endothelial cell damage by measuring the area stained with trypan blue dye, and to confirm the degree of corneal endothelial cell damage resulting from enucleation, corneal buttoning, and storage in donor corneas intended for use in human corneal transplantation. This study was a retrospective analysis of medical records and videos recorded during keratoplasty. Twenty-one corneal buttons of 21 donors that underwent endothelial cell staining using trypan blue for the donor preparation during DALK or DMEK were included in the study. The percentage of stained area in entire corneal endothelia and the percentage of the stained area in the 8-mm diameter circle were quantitatively analyzed using Adobe Photoshop. The mean percentage of the stained area in the entire corneal endothelia in 13 corneas was 8.1 ±â€…13.3% (range, 0.0-56.1%), and the mean percentage of the stained area in a circle with a diameter of 8 mm in 21 corneas was 3.4 ±â€…5.2% (range, 0.0-18.9%). The correlations between the death-to-preservation time, the training duration of the residents who performed donor corneal buttoning, and the percentage of the stained area in the 8-mm diameter circle were not significant(P = .441, P = .495, respectively). Cornea thickness and endothelial cell density did not differ between 10 eyes in the group with the percentage of the stained area in a circle with a diameter of 8 mm <5% and 5 eyes in the group with the percentage more than 5% damage (P = .854, P = .358). The corneal endothelial cell damage could be quantitatively analyzed using trypan blue staining before keratoplasty in donor cornea. The amount of corneal endothelial cell damage in the central 8-mm circle was mostly acceptable, but some cases showed significantly severe endothelial cell damage. The corneal thickness and endothelial cell density did not differ between 10 eyes in the group with the percentage of the stained area in a circle with a diameter of 8 mm <5% and 5 eyes in the group with the percentage more than 5% damage. Therefore, pachymetry and specular microscopy are not sufficient for evaluating donor corneas before keratoplasty.

Relationship between meibomian gland loss in infrared meibography and meibum quality in dry eye patients.

BACKGROUND: In the present study, we evaluated the correlation between meibomian gland dropout and meibum quality in the same central 8 meibomian glands of the eyelid. METHODS: Ninety-nine eyes of 91 patients with dry eye were included in the study. Dropout of the 8 central meibomian glands of the eyelids was graded as 0, 1, 2, or 3, according to the dropout area. The meibum quality was graded as follows: grade 0, no secretion; 1, inspissated/toothpaste consistency; 2, cloudy liquid secretion; and 3, clear liquid secretion. For 68 eyes of 68 patients, correlation analysis between dropout and meibum quality was performed. To precisely analyze the direct correlation between meibomian gland dropout in meibography and meibum quality, we evaluated 31 eyes of 23 patients with focal dropout in meibography. RESULTS: The median (interquartile range) meiboscore was 1.0 (2.0) in the upper eyelids and 0.0 (1.0) in the lower eyelids. The median (interquartile range) meibum quality grade was 3.0 (1.0) in the upper eyelids and 1.0 (1.0) in the lower eyelids. No significant correlation between the meiboscore and meibum quality grade was detected in the upper (p =0.746) or lower (p =0.551) eyelids. Analysis of the direct correlation between meibomian gland dropout in meibography and meibum quality in patients with focal dropout (loss of 1 or 2 adjacent meibomian glands), however, indicated that meibomian glands with dropout secreted little to no meibum. CONCLUSIONS: Overall analysis revealed no relationship between meibomian gland dropout and meibum quality, but more detailed investigation of each meibomian gland alone revealed that meibomian glands with dropout secrete little to no meibum.

Assessment for Macular Thickness after Uncomplicated Phacoemulsification Using Optical Coherence Tomography.

PURPOSE: Macular edema including cystoid macular edema is one of the main causes of unfavorable visual outcomes after cataract surgery. The macular thickness and the occurrence of macular edema after uncomplicated cataract surgery was evaluated using optical coherence tomography (OCT) in this study. METHODS: Macular map images were taken by OCT before surgery and at 1 week, 1 month, and 2 months postsurgery. The subjects were classified into two groups (group 1, patients with no macular edema; group 2, patients with macular edema). Group 2 was defined as increase in central macular thickness (CMT) by 30% compared with that before surgery. The risk factors for macular edema were evaluated. Group 2 was divided into two subgroups: subclinical macular edema (group 2A) and cystoid macular edema (group 2B) and they were assessed in terms of the clinical course of best-corrected visual acuity and CMT. RESULTS: A total of 376 patients were enrolled in this study, of which 36 (9.57%, group 2) showed macular edema measured by OCT after the surgery. Univariate analysis for group 1 and 2 revealed that intracameral injection of epinephrine during phacoemulsification was associated with the development of macular edema. In group 2, five patients (1.33%) developed cystoid macular edema. Statistically significant differences in the clinical course of CMT were observed at 2 months (201.2 ± 23.1, 250.0 ± 29.8, and 371.0 ± 160.3 in group 1, group 2A, and group 2B, respectively; p < 0.001) and 1 month postoperatively (198.5 ± 23.6, 237.8 ± 40.9, and 314.0 ± 104.5 in group 1, group 2A, and group 2B, respectively; p < 0.001). Group 2B required additional treatment and eventually achieved best-corrected visual acuity of >0.2 with CMT in the normal range. CONCLUSIONS: The intracameral injection of epinephrine may cause macular edema after uncomplicated cataract surgery. Examination of CMT using OCT is recommended for the early detection of macular edema.

A Novel Intraocular Lens Simulator that Allows Patients to Experience the World Through Multifocal Intraocular Lenses Before Surgeries.

Purpose: The purpose of this study was to investigate whether the intraocular lens (IOL) simulator can simulate how the world appears to patients with multifocal IOLs by allowing the patients to see far and near objects through the IOL simulator. Methods: Twenty eyes from 20 patients (age = 50-70 years old) were included in the study. The IOL simulator we developed consists of a trial lens frame adapter, a lens tube, a concave lens, a spacer, a wet cell, and an IOL. We used two IOLs: Tecnis monofocal and Tecnis bifocal IOL (add +3.25 diopter [D]). Patients wore a trial lens frame with an IOL simulator on distant corrected trial lenses and underwent the following tests: defocus curve, satisfaction with distance and near vision, halo around the light, and near point accommodation (NPA). To check how the world appears to the patients through this simulator, a machine vision lens and a scientific camera were attached to the simulator, and far and near objects were photographed. Results: In the defocus curve of multifocal IOL, the visual acuity showed the second peak at -4 D. Compared to monofocal IOL, satisfaction with distant vision was slightly worse, more halos were felt, satisfaction with near vision was higher, and the NPA was shorter in multifocal IOL. In the scientific camera test, through the multifocal IOL, the waiting room was blurry, the halo around the ceiling light was prominent, and the characteristics on the near visual acuity chart were clear. Conclusion: Subjects could experience the functions of multifocal IOLs with our newly developed IOL simulator. Translational Relevance: This IOL simulator using geometric optics allows patients to experience the function of multifocal IOLs before cataract surgery.

Conditional Process Analysis for Effective Lens Position According to Preoperative Axial Length.

PURPOSE: To predict the effective lens position (ELP) using conditional process analysis according to preoperative axial length. SETTING: Yeouido St. Mary hospital. DESIGN: A retrospective case series. METHODS: This study included 621 eyes from 621 patients who underwent conventional cataract surgery at Yeouido St. Mary Hospital. Preoperative axial length (AL), mean corneal power (K), and anterior chamber depth (ACD) were measured by partial coherence interferometry. AL was used as an independent variable for the prediction of ELP, and 621 eyes were classified into four groups according to AL. Using conditional process analysis, we developed 24 structural equation models, with ACD and K acting as mediator, moderator or not included as variables, and investigated the model that best predicted ELP. RESULTS: When AL was 23.0 mm or shorter, the predictability for ELP was highest when ACD and K acted as moderating variables (R2 = 0.217). When AL was between 23.0 mm and 24.5 mm or longer than 26.0 mm, the predictability was highest when K acted as a mediating variable and ACD acted as a moderating variable (R2 = 0.217 and R2 = 0.401). On the other hand, when AL ranged from 24.5 mm to 26.0 mm, the model with ACD as a mediating variable and K as a moderating variable was the most accurate (R2 = 0.220). CONCLUSIONS: The optimal structural equation model for ELP prediction in each group varied according to AL. Conditional process analysis can be an alternative to conventional multiple linear regression analysis in ELP prediction.

Comparison of surgically induced astigmatism between anterior and total cornea in 2.2 mm steep meridian incision cataract surgery.

BACKGROUND: This study aimed to compare surgically induced astigmatism (SIA) on the anterior and total cornea during cataract surgery through a 2.2 mm steep meridian incision. METHODS: The study included 69 left eyes of 69 patients who had undergone cataract surgery. The 69 eyes were classified into three subgroups according to the preoperative steep meridian. Following phacoemulsification, an intraocular lens was inserted into the bag. The keratometric measurements were taken 12 months postoperatively, on the anterior cornea (automated keratometer and anterior keratometry [K] from a rotating Scheimpflug camera) and total cornea (equivalent K reading [EKR] 3.0 mm, EKR 4.5 mm, total corneal refractive power (TCRP) 2.0 mm ring, TCRP 3.0 mm zone, TCRP 4.0 mm zone). The SIA was analyzed for each parameter. RESULTS: On the double-angle polar plot, the summated vector mean values of SIA determined by the automated keratometer and Scheimpflug anterior K were 0.28 diopter (axis: 177°) and 0.37 diopter (axis: 175°) in with-the-rule (WTR) astigmatism; 0.03 diopter (axis: 156°) and 0.18 diopter (axis: 177°) in oblique astigmatism; 0.15 diopter (axis: 96°) and 0.17 diopter (axis: 73°) in against-the-rule (ATR) astigmatism. The mean SIAs on the total cornea ranged from 0.31 to 0.42 diopter in WTR astigmatism; from 0.16 to 0.27 diopter in oblique astigmatism; from 0.04 to 0.11 diopter in ATR astigmatism. Mean magnitude SIA ranged from 0.41 to 0.46 diopter on anterior corneal surface and 0.50 to 0.62 diopter on total cornea. J0 and J45 of the posterior cornea showed no significant changes after cataract surgery, and the changes in J0 and J45 did not show any statistical differences between the anterior and total cornea (all p > 0.05). CONCLUSIONS: There were no differences in the summed vector mean values of SIA between the anterior cornea and the total cornea.