Efficacy of Triamcinolone-Soaked Nasal Packing on Endoscopic Dacryocystorhinostomy.

PURPOSE: To evaluate the efficacy of triamcinolone-soaked nasal packing in endoscopic dacryocystorhinostomy (EDCR). METHODS: Patients who underwent EDCR between September 2012 and August 2017 were included. They were assigned to triamcinolone (201 eyes) or control (206 eyes) group based on the order of surgery. Granulation occurrence and outcome were assessed at 3 and 6 months postoperatively, respectively. RESULTS: The success rates were 94.3% (overall anatomical success), 90.4% (complete anatomical success), 92.1% (overall functional success), and 76.7% (complete functional success). The overall functional success rate was significantly higher in the triamcinolone group (95.0% vs. 89.3%, p = 0.033). The overall anatomical success rate (96.0% vs. 92.7%, p = 0.149) and complete functional success rate (79.6% vs. 73.8%, p = 0.166) were also higher in the triamcinolone group, but this difference was not statistically significant. Granulation occurred in 62 eyes (15.2%); the incidence was significantly lower in the triamcinolone group (10.0% vs. 20.4%, p = 0.003). CONCLUSION: The authors suggest that use of triamcinolone-soaked nasal packing in EDCR is effective in significantly reducing the incidence of postoperative granulation and epiphora.

PREVENTING PUPILLARY CAPTURE AFTER VITRECTOMY AND TRANSSCLERAL FIXATION OF AN INTRAOCULAR LENS: Iridotomy Using a Vitrectomy Probe.

PURPOSE: To investigate the effects of concurrent iridotomy using a vitreous cutter probe on the prevention of pupillary capture in patients undergoing transscleral fixation of intraocular lens implantation. METHODS: A total of 79 eyes from 79 patients, who underwent transscleral fixation of intraocular lens without preexisting vitreoretinal disorders and who were followed up for 6 months were included. Subjects were divided into a noniridotomy group (51 eyes) and an iridotomy group (28 eyes). After conventional 23-gauge vitrectomy and transscleral fixation of intraocular lens implantation in all patients, 28 patients underwent concurrent iridotomy intraoperatively. The patients were followed up to evaluate the incidence of surgery-related complications, including pupillary capture. RESULTS: There were no statistically significant differences in the preoperative demographic findings between the two groups (all P > 0.05). There was a significant difference in pupillary capture in 15 eyes (29.4%) of the noniridotomy group, compared with 1 eye (3.6%) of the iridotomy group (P = 0.007). There were no differences in postoperative best-corrected visual acuity between the two groups, and no iridotomy-related complications were observed. CONCLUSION: Concurrent iridotomy using a vitreous cutter probe is an easy, rapid, and effective procedure to prevent possible pupillary capture after combined vitrectomy and transscleral fixation of intraocular lens implantation.

Translation of paired fundus photographs to fluorescein angiographs with energy-based cycle-consistent adversarial networks.

Fluorescein angiography is a crucial examination in ophthalmology to identify retinal and choroidal pathologies. However, this examination modality is invasive and inconvenient, requiring intravenous injection of a fluorescent dye. In order to provide a more convenient option for high-risk patients, we propose a deep-learning-based method to translate fundus photography into fluorescein angiography using Energy-based Cycle-consistent Adversarial Networks (CycleEBGAN) We propose a deep-learning-based method to translate fundus photography into fluorescein angiography using CycleEBGAN. We collected fundus photographs and fluorescein angiographs taken at Changwon Gyeongsang National University Hospital between January 2016 and June 2021 and paired late-phase fluorescein angiographs and fundus photographs taken on the same day. We developed CycleEBGAN, a combination of cycle-consistent adversarial networks (CycleGAN) and Energy-based Generative Adversarial Networks (EBGAN), to translate the paired images. The simulated images were then interpreted by 2 retinal specialists to determine their clinical consistency with fluorescein angiography. A retrospective study. A total of 2605 image pairs were obtained, with 2555 used as the training set and the remaining 50 used as the test set. Both CycleGAN and CycleEBGAN effectively translated fundus photographs into fluorescein angiographs. However, CycleEBGAN showed superior results to CycleGAN in translating subtle abnormal features. We propose CycleEBGAN as a method for generating fluorescein angiography using cheap and convenient fundus photography. Synthetic fluorescein angiography with CycleEBGAN was more accurate than fundus photography, making it a helpful option for high-risk patients requiring fluorescein angiography, such as diabetic retinopathy patients with nephropathy.

Asymmetry between right and left optical coherence tomography images identified using convolutional neural networks.

In a previous study, we identified biocular asymmetries in fundus photographs, and macula was discriminative area to distinguish left and right fundus images with > 99.9% accuracy. The purposes of this study were to investigate whether optical coherence tomography (OCT) images of the left and right eyes could be discriminated by convolutional neural networks (CNNs) and to support the previous result. We used a total of 129,546 OCT images. CNNs identified right and left horizontal images with high accuracy (99.50%). Even after flipping the left images, all of the CNNs were capable of discriminating them (DenseNet121: 90.33%, ResNet50: 88.20%, VGG19: 92.68%). The classification accuracy results were similar for the right and left flipped images (90.24% vs. 90.33%, respectively; p = 0.756). The CNNs also differentiated right and left vertical images (86.57%). In all cases, the discriminatory ability of the CNNs yielded a significant p value (< 0.001). However, the CNNs could not well-discriminate right horizontal images (50.82%, p = 0.548). There was a significant difference in identification accuracy between right and left horizontal and vertical OCT images and between flipped and non-flipped images. As this could result in bias in machine learning, care should be taken when flipping images.

Estimation of best corrected visual acuity based on deep neural network.

In this study, we investigated a convolutional neural network (CNN)-based framework for the estimation of the best-corrected visual acuity (BCVA) from fundus images. First, we collected 53,318 fundus photographs from the Gyeongsang National University Changwon Hospital, where each fundus photograph is categorized into 11 levels by retrospective medical chart review. Then, we designed 4 BCVA estimation schemes using transfer learning with pre-trained ResNet-18 and EfficientNet-B0 models where both regression and classification-based prediction are taken into account. According to the results of the study, the predicted BCVA by CNN-based schemes is close to the actual value such that 94.37% of prediction accuracy can be achieved when 3 levels of difference can be tolerated during prediction. The mean squared error and [Formula: see text] score were measured as 0.028 and 0.654, respectively. These results indicate that the BCVA can be predicted accurately for extreme cases, i.e., the level of BCVA is close to either 0.0 or 1.0. Moreover, using the Guided Grad-CAM, we confirmed that the macula and the blood vessel surrounding the macula are mainly utilized in the prediction of BCVA, which validates the rationality of the CNN-based BCVA estimation schemes since the same area is also exploited during the retrospective medical chart review. Finally, we applied the t-distributed stochastic neighbor embedding to examine the characteristics of CNN-based BCVA estimation schemes. The developed BCVA estimation schemes can be employed to obtain the objective measurement of BVCA as well as the medical screening of people with poor access to medical care through smartphone-based fundus imaging.

Asymmetry between right and left fundus images identified using convolutional neural networks.

We analyzed fundus images to identify whether convolutional neural networks (CNNs) can discriminate between right and left fundus images. We gathered 98,038 fundus photographs from the Gyeongsang National University Changwon Hospital, South Korea, and augmented these with the Ocular Disease Intelligent Recognition dataset. We created eight combinations of image sets to train CNNs. Class activation mapping was used to identify the discriminative image regions used by the CNNs. CNNs identified right and left fundus images with high accuracy (more than 99.3% in the Gyeongsang National University Changwon Hospital dataset and 91.1% in the Ocular Disease Intelligent Recognition dataset) regardless of whether the images were flipped horizontally. The depth and complexity of the CNN affected the accuracy (DenseNet121: 99.91%, ResNet50: 99.86%, and VGG19: 99.37%). DenseNet121 did not discriminate images composed of only left eyes (55.1%, p = 0.548). Class activation mapping identified the macula as the discriminative region used by the CNNs. Several previous studies used the flipping method to augment data in fundus photographs. However, such photographs are distinct from non-flipped images. This asymmetry could result in undesired bias in machine learning. Therefore, when developing a CNN with fundus photographs, care should be taken when applying data augmentation with flipping.

Machine learning-based optimization of pre-symptomatic COVID-19 detection through smartwatch.

Patients with weak or no symptoms accelerate the spread of COVID-19 through various mutations and require more aggressive and active means of validating the COVID-19 infection. More than 30% of patients are reported as asymptomatic infection after the delta mutation spread in Korea. It means that there is a need for a means to more actively and accurately validate the infection of the epidemic via pre-symptomatic detection, besides confirming the infection via the symptoms. Mishara et al. (Nat Biomed Eng 4, 1208-1220, 2020) reported that physiological data collected from smartwatches could be an indicator to suspect COVID-19 infection. It shows that it is possible to identify an abnormal state suspected of COVID-19 by applying an anomaly detection method for the smartwatch's physiological data and identifying the subject's abnormal state to be observed. This paper proposes to apply the One Class-Support Vector Machine (OC-SVM) for pre-symptomatic COVID-19 detection. We show that OC-SVM can provide better performance than the Mahalanobis distance-based method used by Mishara et al. (Nat Biomed Eng 4, 1208-1220, 2020) in three aspects: earlier (23.5-40% earlier) and more detection (13.2-19.1% relative better) and fewer false positives. As a result, we could conclude that OC-SVM using Resting Heart Rate (RHR) with 350 and 300 moving average size is the most recommended technique for COVID-19 pre-symptomatic detection based on physiological data from the smartwatch.

Development of fully automated anterior chamber cell analysis based on image software.

Optical coherence tomography (OCT) is a noninvasive method that can quickly and accurately examine the eye at the cellular level. Several studies have used OCT for analysis of anterior chamber cells. However, these studies have several limitations. This study was performed to supplement existing reports of automated analysis of anterior chamber cell images using spectral domain OCT (SD-OCT) and to compare this method with the Standardization of Uveitis Nomenclature (SUN) grading system. We analyzed 2398 anterior segment SD-OCT images from 34 patients using code written in Python. Cell density, size, and eccentricity were measured automatically. Increases in SUN grade were associated with significant cell density increases at all stages (p < 0.001). Significant differences were observed in eccentricity in uveitis, post-surgical inflammation, and vitreous hemorrhage (p < 0.001). Anterior segment SD-OCT is reliable, fast, and accurate means of anterior chamber cell analysis. This method showed a strong correlation with the SUN grade system. Also, eccentricity could be helpful as a supplementary evaluation tool.

Modified ocular surface disease index as a screening criteria for dry eye syndrome presenting after successful dacryocystorhinostomy.

OBJECTIVE: To find preoperative screening criteria for dry eye syndrome (DES) that present after successful endoscopic dacryocystorhinostomy (EDCR). METHODS: We retrospectively analyzed medical records of 110 patients who underwent EDCR for nasolacrimal duct obstruction. DES diagnostic criteria were defined as tear break-up time (TBUT) less than 10 seconds, and ocular surface disease index (OSDI) score greater than 13 points. After EDCR, patients were divided into DES group and control group according to the DES diagnostic criteria. Preoperative OSDI score alone or in combination of preoperative TBUT and OSDI score were used to find screening criteria, which could discriminate the two groups preoperatively with a high positive predictive value (PPV). Criteria A was set same as the diagnostic criteria of DES, and Criteria B and C were set to improve PPV by increasing specificity while maintaining similar sensitivity to Criteria A. RESULTS: Thirty patients (27.3%) were diagnosed with DES after EDCR, while 80 patients (72.7%) were normal. In patients with DES, preoperative TBUT was not different (p = 0.851), but OSDI score was significantly higher (p<0.001). Criteria A showed a sensitivity of 73.3%, specificity of 55.0%, and PPV of 38.0%. Criteria B and C excluded preoperative TBUT, which had no difference between the two groups, and set screening criteria with preoperative OSDI score alone. Criteria B (preoperative OSDI score of 19.6 points or more) showed a sensitivity of 75.0%, specificity of 60.6%, PPV of 41.7% and AUC of 0.739 (p < 0.001). Criteria C was consisted of 5 out of 12 OSDI items that showed significant differences between the two groups; blurred vision, reading, working with a computer, low humidity, and air conditioning. Criteria C (preoperative 5-item OSDI score of 24.4 points or more) was a better predictability, with a sensitivity of 75.0%, specificity of 71.3%, PPV of 49.5%, and AUC of 0.804 (p < 0.001). The AUC of Criteria C was significantly higher than that of Criteria B (p = 0.0037). CONCLUSION: DES occurred after successful EDCR in 27.3% of patients, and an OSDI questionnaire helped to screen DES. The predictability could improve using the modified OSDI score which showed noticeable difference in five OSDI items before and after EDCR.

Two-Year Reproducibility of Axial Length Measurements after Combined Phacovitrectomy for Epiretinal Membrane, and Refractive Outcomes.

PURPOSE: To determine the long-term reproducibility of axial length measurements and mean postoperative prediction errors after combined phacovitrectomy in patients with idiopathic epiretinal membranes. DESIGN: Retrospective cohort study. METHODS: The study included 43 patients who underwent combined phacovitrectomy and 30 patients who underwent only phacoemulsification. To determine the effect of vitrectomy, we compared patients treated with phacoemulsification only versus those treated with combined phacovitrectomy. Axial lengths were measured three times with a one-year interval, and the intraclass correlation coefficient (ICC), coefficient of variation (CV), and test-retest standard deviation (TRTSD) were assessed. RESULTS: There was no significant change in axial length, and axial length measurements showed high reproducibility in all groups. ICC, CV, and TRTSD values were 0.997, 0.24%, and 0.056, respectively, for the vitrectomized eyes. The mean postoperative prediction error was -0.37 diopters(D) in vitrectomized eyes (p < 0.001), while it was +0.11 D in patients with phacoemulsification (p = 0.531). The myopic shift was more obvious in eyes with a shallower anterior chamber (p = 0.008) and a thicker lens (p = 0.025). CONCLUSIONS: Axial length measurements showed excellent long-term reproducibility at 2 years after combined phacovitrectomy. Myopic shifts were observed after combined phacovitrectomy, which was probably due to changes in the effective lens position after combined phacovitrectomy, rather than to changes in the axial length.

The Difference in Repeatability of Automated Superficial Retinal Vessel Density according to the Measurement Area Using OCT Angiography.

PURPOSE: To evaluate the difference in the repeatability of automated superficial retinal vessel density and foveal avascular zone (FAZ) metrics according to the measurement area of optical coherence tomography angiography (OCTA). METHODS: A total of 127 normal eyes from 127 healthy subjects were included. Macular angiography images were acquired from all subjects using the Zeiss Cirrus 5000 with AngioPlex™ OCTA software. Scans of 3 × 3 mm and 6 × 6 mm were each performed twice in a randomly arranged sequence. Vessel density (VD), perfusion density (PD), and FAZ metrics of the superficial capillary plexus were calculated automatically for all scans, and the repeatabilities for both scan patterns were assessed based on intraclass correlation (ICC), coefficient of variation (CV), and coefficient of repeatability (CR) parameters. The average measured values in the two scan patterns were also compared. RESULTS: VD was significantly greater in the 3 × 3 mm scan than in the 6 × 6 mm scan according to all parameters, whereas PD was significantly less in the 3 × 3 mm scan than in the 6 × 6 mm scan. The ICCs for VDs in the central fovea were 0.826 and 0.741 for the 3 × 3 and 6 × 6 mm scans, respectively, and the CVs were 8.00% and 12.75%. For PDs, the ICCs were 0.839 and 0.762 and the CVs were 9.32% and 14.90%. The FAZ metrics in the 3 × 3 mm scan showed good repeatability with an ICC >0.75 and a CV <10.0%. However, all ICCs for the 6 × 6 mm scans were <0.75, and the CVs were all >10%. CONCLUSIONS: The 6 × 6 mm macular angiography scans resulted in lower repeatabilities than the 3 × 3 mm scans according to all OCTA parameters, particularly in the central fovea and FAZ metrics. The 3 × 3 mm scan was more suitable than the 6 × 6 mm scan for analyzing macular microvascular density and FAZ metrics.

Full thickness macular hole formation and spontaneous closure associated with branch retinal vein occlusion in a vitrectomized eye: A case report.

RATIONALE: Macular hole (MH) formation after vitrectomy is rare and it may be due to several mechanisms associated with change of foveolar anatomy by vitrectomy. If a MH develops after vitrectomy, surgical treatments including internal limiting membrane peeling and intravitreal gas injection are usually needed for repair of hole. Spontaneous closure of MH is much rarer. PATIENT CONCERNS: A 66-year-old patient had a vitrectomy for rhegmatogenous retinal detachment not involving the macula of the right eye. Eight months after the vitrectomy, the visual acuity decreased and full-thickness defect of macula, epiretinal membrane progression, intraretinal cysts, and flame shape hemorrhage along with superior temporal vascular arcade were observed on fundus examination and optical coherence tomography. DIAGNOSES: MH and branch retinal vein occlusion (BRVO) accompanying cystoid macular edema (CME) were both present on her right eye. Thus, we planned a surgery for MH repair. INTERVENTIONS: The status of MH was observed while waiting the surgery schedule. At 2 weeks after detection of the MH, optical coherence tomography showed that intraretinal cysts had decreased in extent and the inner wall of the MH had contracted; 4 weeks later, the MH was closed with a subtle subretinal space. OUTCOMES: The fovea was well-maintained with a complete closure for 9 months. LESSONS: MH formation and spontaneous closure occurred in association with BRVO accompanying CME in a patient who had a vitrectomy. In vitrectomized eyes, physicians should consider the possibility of MH development in association with BRVO, and possible spontaneous closure of the MH in accordance with CME resolution.

Phosphorylation of STAT3 and ERBB2 mediates hypoxia­induced VEGF release in ARPE­19 cells.

Neovascularization in the retina can cause loss of vision. Vascular endothelial growth factor (VEGF) serves an important role in the pathogenesis of retinal vascular diseases. Hypoxia is a notable cause of VEGF release and both STAT3 and ERBB2 are known to be associated with VEGF. In addition, STAT3 and ERBB2 interact with each other. In the present study, it was hypothesized that signal transducer and activator of transcription 3 (STAT3) and erbB­2 receptor tyrosine kinase 2 (ERBB2) may be involved in the regulation of hypoxia­induced VEGF in the retina. Cells of the retinal pigment epithelium (RPE) are an important source of VEGF. Therefore, the RPE­derived human cell line ARPE­19 was exposed to hypoxia. Hypoxia­induced phosphorylation of STAT3 and ERBB2 in ARPE­19 cells was decreased by AG490, an inhibitor of Janus kinase 2, as were hypoxia­induced VEGF release and tube formation in human umbilical vein endothelial cells. Thus, phosphorylation of ERBB2 and STAT3 regulates hypoxia­induced VEGF release in ARPE­19 cells. The results of the present study suggested that inhibition of ERBB2 and STAT3­mediated pathways under hypoxia may represent a new strategy for treating retinal vascular disease.

Surgical outcomes of endoscopic dacryocystorhinostomy: analysis of age effect.

There is limited evidence in literature determining age effect on outcomes of endoscopic dacryocystorhinostomy (EDCR) in adult patients with primary acquired nasolacrimal duct obstruction (NLDO). We aimed to analyze the outcomes of EDCR according to age in primary acquired NLDO. A retrospective study was performed on consecutive adult patients and patients were divided into two age groups; group 1 (aged to 61 years) and group 2 (aged 62 to 89 years) based on the average value. The minimum required follow-up period was 6 months. A total of 441 EDCRs performed in 342 patients were enrolled. The anatomical success rate was not significantly different between the two groups (91.8% and 88.2%, P = 0.209). However, the functional success rate was significantly lower in the group 2 (85.1% and 76.9%; P = 0.036). Functional failure was associated with old age and a history of diabetes mellitus (P = 0.024 and P = 0.008). In subgroup analysis of patients with anatomical success but functionally failed EDCR, group 2 had significantly more comorbid conditions such as eyelid laxity (P = 0.026). In conclusion, the comorbid conditions which increase with age may affect functional outcome, especially eyelid laxity, careful preoperative examination of the eyelid and conjunctiva should be emphasized to lacrimal surgeons before performing EDCR.

Long-Term Reproducibility of Axial Length after Combined Phacovitrectomy in Macula-sparing Rhegmatogenous Retinal Detachment.

There is a myopic shift in the final measured spherical equivalent following combined phacovitrectomy compared to the predicted postoperative value. This change in myopia is known to be associated with gas tamponade, but it also occurs in patients who do not have gas tamponade, and even when vitrectomy is performed in the pseudophakic eye. In this study, we focused on the long-term reproducibility of axial length after combined phacovitrectomy in patients with macula-sparing rhegmatogenous retinal detachment. Before surgery, one year after surgery, and two years after surgery, bilateral axial lengths were measured using partial interferometry. To confirm whether axial lengths changed after surgery, we conducted confidence analyses using the intraclass correlation coefficient (ICC), coefficient of variation (CV), and test-retest standard deviation (TRTSD). The preoperative mean axial length was 25.03 ± 1.69 mm in the affected eyes and 24.96 ± 1.70 mm in the fellow eyes. The ICC, CV, and TRTSD were 0.97, 0.45, and 0.114 in affected eyes and 0.98, 0.66, and 0.167 in fellow eyes, respectively, which shows a high level of reproducibility. Prediction errors for postoperative spherical equivalents measured using partial interferometry were -0.41 ± 0.67 diopters (p = 0.001), respectively, which shows a remarkable myopic shift. Correlation analyses indicated that this myopic shift was significant in eyes with a shallower anterior chamber and a thicker lens. In macula-sparing RRD patients, the axial length showed excellent long-term reproducibility two years after vitrectomy, cataract surgery, and gas tamponade. The myopic shift after surgery was therefore caused by factors that may have affected the intraocular lens position, such as preoperative anterior chamber depth and lens thickness, rather than a change in the axial length.

Long-term Effect of Panretinal Photocoagulation on Spectral Domain Optical Coherence Tomography Measurements in Diabetic Retinopathy.

PURPOSE: To evaluate the effects of panretinal photocoagulation on spectral domain optical coherence tomography measurements in diabetic retinopathy by comparing the thicknesses of the central macula, retinal nerve fiber layer, and ganglion cell layer, we used a Cirrus HD OCT® (Carl Zeiss Meditec, Dublin, CA, USA) in normal and diabetic retinopathy cohorts. METHODS: We analyzed patients who visited our retinal clinic between May 2013 and July 2014. The patients were classified into four groups: normal (Group A), diabetes without diabetic retinopathy (Group B), severe nonproliferative or proliferative diabetic retinopathy (Group C), and at least 3 years after panretinal photocoagulation treatment (Group D). The mean thicknesses of the macula, retinal nerve fiber layer, and ganglion cell layer in each group were compared by measuring a macular cube 512 × 128 scan and an optic disc cube 200 × 200 scan twice. RESULTS: In total, 154 patients were enrolled. The mean thickness of the central macula in groups A to D was 257.2, 256.8, 257.4, and 255.6 µm, respectively, and did not differ significantly. The mean thickness of the RNFL in group A to D was 96.8, 96.5, 97.2, and 92.8 µm, respectively, and was significantly lower in group D (decreased in the inferior, superior, and nasal sectors, but increased in the temporal). The mean thickness of the ganglion cell layer was also significantly lower in group D (A, 84.5 µm; B, 84.4 µm; C, 82.5 µm; D, 78.5 µm). CONCLUSIONS: The mean thicknesses of the retinal nerve fiber and ganglion cell layers were decreased significantly in eyes with diabetic eye disease treated with panretinal photocoagulation compared to normal or eyes with diabetic eye disease that had not been laser-treated. Laser treatment might have altered the thickness of the inner layer of the retina, and such changes should be considered in diabetic retinopathy patients after panretinal photocoagulation treatment.

Difference in patterns of retinal ganglion cell damage between primary open-angle glaucoma and non-arteritic anterior ischaemic optic neuropathy.

PURPOSE: To compare the patterns of retinal ganglion cell damage between primary open-angle glaucoma (POAG) and non-arteritic anterior ischaemic optic neuropathy (NAION). METHODS: In total, 35 eyes with unilateral NAION, and 70 age- and average peripapillary retinal nerve fibre layer (RNFL) thickness-matched eyes with POAG, were enrolled as disease groups; 35 unaffected fellow eyes of the NAION, and 70 age- and refractive error-matched normal subjects for the POAG, were enrolled as their control groups, respectively. The peripapillary RNFL thickness and macular ganglion cell plus inner plexiform layer (GCIPL) thickness were compared between the disease groups and their controls, and between the two disease groups. RESULTS: Mean RNFL thicknesses at the 1 and 2 o'clock (superonasal) positions were thinner in NAION than in POAG (both p < 0.05). Mean RNFL thickness at 7 o'clock (inferotemporal) was thinner in POAG than in NAION (p = 0.001). Although there was no significant difference between NAION and POAG in average GCIPL thickness, all of the sectoral GCIPL thicknesses were thinner in NAION (all p < 0.05), except in the inferior and inferotemporal sectors. The ranges of the clock-hour RNFL with damage greater than the average RNFL thickness reduction, versus fellow eyes and control eyes, were 7 hours in NAION and 4 hours in POAG. CONCLUSIONS: The more damaged clock-hour RNFL regions differed between NAION (1 and 2 o'clock) and POAG (7 o'clock). Most sectoral GCIPL thicknesses were thinner in NAION than in POAG.

Changes in Axial Length and Refractive Error After Noninvasive Normalization of Intraocular Pressure From Elevated Levels.

PURPOSE: To explore the changes in axial length and refractive error after noninvasive normalization of intraocular pressure (IOP) from elevated levels. DESIGN: A prospective observational study. METHODS: We enrolled 51 consecutive patients with abnormally elevated unilateral IOP (≥10 mm Hg compared with that of the fellow eye, in which the IOP was ≤21 mm Hg). In all patients, the keratometric value and axial length were obtained with the aid of an IOLMaster before and after IOP normalization (defined as attainment of an IOP difference of ≤3 mm Hg compared with the fellow eye, with or without topical application of ocular hypotensive therapy). We focused principally on IOP, axial length, the keratometric value, and the predicted refractive difference (the predicted refractive error after IOP normalization upon placement of an IOL with a power for emmetropia correction determined prior to IOP normalization). RESULTS: The axial length was significantly reduced from 23.5 to 23.3 mm after IOP normalization, from 45.9 mm Hg to 14.3 mm Hg (P < .001). The change in IOP correlated with that of the axial length (r = 0.826, P < .001), but not with the change in the keratometric value (P = .618). The change in axial length per 10 mm Hg IOP decrease was -0.06 mm (P < .001). The IOP change was correlated with the predicted refractive difference (r = 0.693, P < .001); the predicted refractive difference per 10 mm Hg IOP decrease was +0.15 diopter (P < .001). CONCLUSIONS: The axial length decreased and the predicted refractive difference increased (hyperopia) as IOP decreased. Therefore, a possible risk of postoperative hyperopic shift should be considered when biometric examination for IOL power calculation is performed in a patient with an abnormally elevated IOP.