Glaucoma Prediction Models Based on Ocular and Systemic Findings.

INTRODUCTION: Our aim was to explore the impact of various systemic and ocular findings on predicting the development of glaucoma. METHODS: Medical records of 37,692 consecutive patients examined at a single medical center between 2001 and 2020 were analyzed using machine learning algorithms. Systemic and ocular features were included. Univariate and multivariate analyses followed by CatBoost and Light gradient-boosting machine prediction models were performed. Main outcome measures were systemic and ocular features associated with progression to glaucoma. RESULTS: A total of 7,880 patients (mean age 54.7 ± 12.6 years, 5,520 males [70.1%]) were included in a 3-year prediction model, and 314 patients (3.98%) had a final diagnosis of glaucoma. The combined model included 185 systemic and 42 ocular findings, and reached an ROC AUC of 0.84. The associated features were intraocular pressure (48.6%), cup-to-disk ratio (22.7%), age (8.6%), mean corpuscular volume (MCV) of red blood cell trend (5.2%), urinary system disease (3.3%), MCV (2.6%), creatinine level trend (2.1%), monocyte count trend (1.7%), ergometry metabolic equivalent task score (1.7%), dyslipidemia duration (1.6%), prostate-specific antigen level (1.2%), and musculoskeletal disease duration (0.5%). The ocular prediction model reached an ROC AUC of 0.86. Additional features included were age-related macular degeneration (10.0%), anterior capsular cataract (3.3%), visual acuity (2.0%), and peripapillary atrophy (1.3%). CONCLUSIONS: Ocular and combined systemic-ocular models can strongly predict the development of glaucoma in the forthcoming 3 years. Novel progression indicators may include anterior subcapsular cataracts, urinary disorders, and complete blood test results (mainly increased MCV and monocyte count).

Prevalence of common and rare ophthalmic findings in adults attending a medical survey institute.

PURPOSE: To examine the ophthalmic data from a large database of people attending a general medical survey institute, and to investigate ophthalmic findings of the eye and its adnexa, including differences in age and sex. METHODS: Retrospective analysis including medical data of all consecutive individuals whose ophthalmic data and the prevalences of ocular pathologies were extracted from a very large database of subjects examined at a single general medical survey institute. RESULTS: Data were derived from 184,589 visits of 3676 patients (mean age 52 years, 68% males). The prevalence of the following eye pathologies were extracted. Eyelids: blepharitis (n = 4885, 13.3%), dermatochalasis (n = 4666, 12.7%), ptosis (n = 677, 1.8%), ectropion (n = 73, 0.2%), and xanthelasma (n = 160, 0.4%). Anterior segment: pinguecula (n = 3368, 9.2%), pterygium (n = 852, 2.3%), and cataract or pseudophakia (n = 9381, 27.1%). Cataract type (percentage of all phakic patients): nuclear sclerosis (n = 8908, 24.2%), posterior subcapsular (n = 846, 2.3%), and capsular anterior (n = 781, 2.1%). Pseudophakia was recorded for 697 patients (4.6%), and posterior subcapsular opacification for 229 (0.6%) patients. Optic nerve head (ONH): peripapillary atrophy (n = 4947, 13.5%), tilted disc (n = 3344, 9.1%), temporal slope (n = 410, 1.1%), ONH notch (n = 61, 0.2%), myelinated nerve fiber layer (n = 94, 0.3%), ONH drusen (n = 37, 0.1%), optic pit (n = 3, 0.0%), and ON coloboma (n = 4, 0.0%). Most pathologies were more common in males except for ONH, and most pathologies demonstrated a higher prevalence with increasing age. CONCLUSIONS: Normal ophthalmic data and the prevalences of ocular pathologies were extracted from a very large database of subjects seen at a single medical survey institute.

Early versus delayed photodynamic therapy for chronic central serous chorioretinopathy.

PURPOSE: Central serous chorioretinopathy (CSCR) patients are sometimes referred to Photodynamic Therapy (PDT) with very long-term disease. The purpose of this study was to analyze the results of PDT in CSCR eyes with long-standing disease. METHODS: The medical records of the patients that underwent PDT for CSCR between 2009 and 2019 were reviewed. Cases were divided into two groups based on the duration of disease before PDT treatment: early treatment (3 to 6 months) and delayed treatment (longer than 6 months). The treatment was defined as successful when the subfoveal fluid was absorbed during follow-up. RESULTS: The PDT treatment was successful in 76% and 77% of eyes in the early and delayed treatment groups, respectively. Both groups showed significant improvement in central retina measurements at the 3-months follow-up which persisted to the last follow-up visit. The visual acuity (VA) at baseline was significantly worse in the delayed treatment group (0.5 ± 0.26 vs. 0.3 ± 0.24, P = 0.042) and improved in both groups but remained low in the delayed treatment group during the study. CONCLUSION: We suggest that if CSCR is not spontaneously improving over 3 months the patient should be offered PDT, to prevent VA loss from the long-term presence of subretinal fluid in the macula. PDT is not associated with loss of vision in eyes with chronic CSCR, and can be safely used in eyes with relatively good VA.

OCULAR SURFACE TEMPERATURE DIFFERENCES IN RETINAL VASCULAR DISEASES.

PURPOSE: To define the effect of age-related macular degeneration (AMD) and diabetic retinopathy (DR) on the ocular thermographic profile. METHODS: This retrospective cross-sectional study included subjects diagnosed with DR or AMD between January and April 2019. Individuals without ocular disease served as controls. A thermal imaging camera was used for ocular surface temperature (OST) acquisition. The mean temperatures of the medial cantus, lateral cantus, and cornea were calculated. RESULTS: Thermographic images were obtained from 133 subjects (260 eyes, 97 DR and 163 AMD) and 48 controls (55 eyes). Ocular surface temperature was higher among patients with AMD and lowest among patients with DR (P < 0.001). A subgroup analysis revealed that eyes with diabetic macular edema had significantly higher OSTs than DR eyes without diabetic macular edema. Moreover, the OST in eyes with diabetic macular edema was similar to the measurements of the AMD group. There were no differences in OSTs between neovascular and nonneovascular AMD eyes. CONCLUSION: Although AMD and DR are considered posterior segment conditions, their effect on OST implies that the entire globe is involved. Although both conditions result from similar multifactorial pathophysiologic changes, the differences in OST between DR and AMD might be due to dissimilarity in the balance of pathologic processes involved in each condition. Further research is required to better understand the pathophysiology of these diseases and their effect on OST as well as to determine the effect of vasculature, circulation, and tissue metabolism on ocular temperature.

Cognitive Performance of Patients With Multiple Sclerosis and Optic Neuritis at Presentation.

BACKGROUND: Cognitive dysfunction is common among patients with multiple sclerosis (MS), but the effect of coexisting optic neuritis (ON) at the first presentation of multiple sclerosis on the course of cognitive decline is unknown. The purpose of this study was to assess whether ON at presentation has any effect on the progression of cognitive decline in MS. METHODS: Historical cohort study. We retrospectively compared the cognitive performance of patients with relapsing-remitting MS with and without ON at the time of MS diagnosis. Subjects were included if cognitive test results were available both at baseline and after at least 36 months from presentation and grouped based on the presence (MS-ON) or absence (MS-non-ON) of optic neuritis at presentation. RESULTS: One hundred seventy consecutive subjects with MS were found suitable, with a 1:2 male:female ratio and a mean age at diagnosis of 33.0 ± 10.9 years. Forty-six patients (27.1%) presented with ON. No significant differences were found in cognitive performance at onset between the 2 groups. Both groups had a similar follow-up duration. The prevalence of cognitive decline in the general score was significantly higher in the MS-ON group compared with the MS-non-ON group (6.5% vs 0%, respectively; P < 0.001), as well as in the attention (8.7% vs 1.6%; P = 0.046) and the executive function (17.4% vs 2.4%; P = 0.001) domains. CONCLUSIONS: Optic neuritis at presentation of MS is associated with a higher prevalence of cognitive decline over time. Potential benefit of early intervention to prevent cognitive decline may be warranted.

The negative impact of COVID-19 pandemic on age-related macular degeneration patients treated with intravitreal bevacizumab injections.

PURPOSE: COVID-19 emerged in the end of 2019 and was declared a worldwide pandemic shortly after. Social distancing and lockdowns resulted in lower compliance in intravitreal injections and office visits. We aimed to assess clinical outcomes among patients who missed these visits compared to those who arrived as planned. METHODS: Patients who missed or were late to office visits or intravitreal injections were defined as non-adherent and were compared to adherent patients. Our main outcomes were the need for subsequent injections, mean change in best-corrected visual acuity (BCVA), and central macular thickness (CMT). RESULTS: This study included 77 patients (24 adherent and 53 non-adherent). The mean BCVA remained stable during the study period for the adherent group (p = 0.159) and worsened in the non-adherent group (p < 0.001). Changes in CMT and maximum thickness were not significant for either group. A higher proportion of patients in the non-adherent group needed subsequent intravitreal injections (49% vs 20%, p = 0.014). CONCLUSION: The findings demonstrate the negative implications of the COVID-19 pandemic and the effect of deferring bevacizumab injections among individuals with age-related macular degeneration. This emphasizes the importance of a scheduled follow-up, also during a pandemic.

New insight into the physiologic function of Müller's muscle.

PURPOSE: Müller's muscle is a sympathetically innervated smooth muscle which serves as an accessory upper eyelid retractor. Its physiologic function and purpose have not yet been clearly defined. We hypothesize that sympathetic innervation to Müller's muscle serves to adjust the upper eyelid's position to variations in pupil size in response to changes in light intensity. METHODS: This is a single center cross-sectional study. Healthy volunteers were asked to fixate on a distant non-accommodative target, and a video scan of the anterior segment was performed for each subject's right eye using the Heidelberg Spectralis® optical coherence tomography scanner in infrared mode. The video was taken both in photopic and scotopic conditions, recording the resultant transition of the pupil and eyelids. The pupil diameter (PD), upper eyelid margin-to-reflex distance (MRD1), lower eyelid margin-to-reflex distance (MRD2), and vertical palpebral fissure height (PFH) were measured. RESULTS: Thirty-three healthy volunteers (19 women, 57.6%) with a median age of 40 years (range 30-58) were included. The mean PD under photopic conditions increased significantly under scotopic conditions, from 3483 ± 521 µm to 6135 ± 703 µm, respectively (P < 0.0001). An increase in MRD1 was observed following transition from light to dark, with a mean change of 348 ± 311 µm (P < 0.0001). There was no significant change in MRD2. CONCLUSIONS: Upper eyelid retraction occurs after transition from photopic to scotopic conditions. This movement suggests the existence of an "eyelid-light reflex" involving Müller's muscle that adjusts the position of the eyelids as the pupil dilates under scotopic conditions.

Modeling Social Distancing Strategies to Prevent SARS-CoV-2 Spread in Israel: A Cost-Effectiveness Analysis.

OBJECTIVES: While highly effective in preventing SARS-CoV-2 spread, national lockdowns come with an enormous economic price. Few countries have adopted an alternative "testing, tracing, and isolation" approach to selectively isolate people at high exposure risk, thereby minimizing the economic impact. To assist policy makers, we performed a cost-effectiveness analysis of these 2 strategies. METHODS: A modified Susceptible, Exposed, Infectious, Recovered, and Deceased (SEIRD) model was employed to assess the situation in Israel, a small country with ∼9 million people. The incremental cost-effectiveness ratio (ICER) of these strategies as well as the expected number of infected individuals and deaths were calculated. RESULTS: A nationwide lockdown is expected to save, on average, 274 (median 124, interquartile range: 71-221) lives compared to the "testing, tracing, and isolation" approach. However, the ICER will be, on average, $45 104 156 (median $49.6 million, interquartile range: 22.7-220.1) to prevent 1 case of death. CONCLUSION: A national lockdown has a moderate advantage in saving lives with tremendous costs and possible overwhelming economic effects. These findings should assist decision makers dealing with additional waves of this pandemic.

A novel EyePhone© App for improving adherence to glaucoma therapy.

PURPOSE: Despite advances in glaucoma treatment options, patient adherence and compliance remain very low. The EyePhone© App is a free non-commercial reminder application designed specifically for the needs of glaucoma patients. In this study, we evaluated its usefulness in improving adherence to medical treatment among glaucoma patients. METHODS: This is a prospective multicenter interventional study. Glaucoma patients were recruited from a tertiary center and a large community glaucoma service center. After a short explanation, the EyePhone© App was installed on their smartphone device, and the notifications for the current medical treatment were entered. After enrollment and at 1-month follow-up, subjects completed the Morisky Medication Adherence Scale (MMAS-8) and the Quality of Life and Glaucoma 17-item (GlauQOL-17) questionnaires for evaluation of adherence and QOL, respectively. RESULTS: In the study, 133 patients (71 men and 62 women) aged 62±15.5 years and using 2.0±0.9 IOP-lowering drugs participated. The proportion of highly adherent subjects improved from 29.3% (39/133) at baseline to 42.1% (56/133) at follow-up (P < 0.001), and the proportion of poorly adherent subjects decreased from 29.3 (39/133) to 20.3% (27/133) at follow-up (P = 0.012). QOL also improved, as evidenced by a significant increase in the GlauQOL-17 score (P < 0.05). In a subgroup of patients for whom IOP measurements were available, IOP reduced by 0.92 mmHg (P = 0.069). CONCLUSIONS: Significant improvements in glaucoma adherence and QOL were achieved among poorly adherent glaucoma patients after 1 month of using the EyePhone© App.

Er:YAG laser-assisted filtration surgery: initial results in rabbits.

BACKGROUND: Glaucoma is a leading cause of global blindness, especially preventable blindness. The increased prevalence of glaucoma has led to a growing demand for newer, safer, more rapid, and simpler treatments for the reduction of intraocular pressure (IOP). In this study, we evaluated the safety and feasibility of performing filtration glaucoma surgery with an Ab-Interno Er:YAG laser in rabbits. METHODS: Nine New Zealand White rabbits age 16 weeks were studied. After subconjunctival injection of mitomycin C (MMC), a novel Ab-Interno Er:YAG laser probe was inserted into the anterior chamber (AC) through a clear corneal 1 mm paracentesis and directed at the trabecular meshwork adjacent to the MMC injection area. A pulsed laser beam was applied to create a patent sclerostomy connecting the AC to the subconjuctival space, resulting in a filtering bleb. The laser system used was the Er:YAG laser system - LAS25-FCU, (Pantec Biosolutions AG, Liechtenstein). Parameters used: Wave lengh: 2940 nm, Pulse length: 100-400 µsec,frequency: 250 Hz. Average laser power in accordance to the fiber tip diameter: 0.85 W(range 0.8-0.92 W). Complete ocular exams, including IOP measurements, were performed on 1, 7, 14, and 23 days postoperatively. Three rabbits were sacrificed on days 1, 14, and 23, and histological examinations were performed on all nine eyes. RESULTS: All procedures resulted in a functional medium-large superior bleb without significant complications. The bleb was sustained in all rabbits by day 14 and in one of the three rabbits that reached the last follow-up at 23 days. No cases of postoperative hypotony were observed. There was a transient significant reduction in mean IOP on postoperative days 5 and 7 (P = 0.028). Histopathological analysis revealed a patent full-thickness scleral tunnel with only a minor degree of surrounding coagulation necrosis. CONCLUSIONS: The Ab-Interno laser sclerostomy procedure is potentially safe and effective based on initial experience in an in-vivo rabbit animal model.

Changes in Refraction and Visual Acuity after Upper Eyelid Blepharoplasty versus Posterior Approach Ptosis Procedures.

PURPOSE: To evaluate surgically induced refractive changes (SIRC) and visual acuity (VA) changes after blepharoplasty combined with posterior approach ptosis surgery (Müller's muscle-conjunctival resection [MMCR]) versus upper eyelid blepharoplasty alone. METHODS: In this prospective, comparative, clinical study on patients undergoing MMCR and blepharoplasty, comprehensive ophthalmic examinations were performed preoperatively and 3 months postoperatively. SIRC were calculated with the 10-step Holladay method. RESULTS: Fifty-six patients participated in the study, 31 in the blepharoplasty group and 25 in the ptosis group. logMAR VA improved significantly after surgery in both groups (p < 0.001). In both groups, most patients showed significant changes in SIRC sphere and spherical equivalent of >0.5 D (blepharoplasty group: 61.29 and 67.74%; ptosis group: 72.72 and 72.72%, respectively). Patients undergoing combined blepharoplasty ptosis surgery showed the greatest SIRC cylinder. CONCLUSIONS: Upper eyelid blepharoplasty with or without MMCR is associated with significant SIRC 3 months postoperatively. This may affect decision-making for all patients, especially for those who intend to seek refractive correction in addition to the index upper eyelid surgery.

OPTICAL DENSITY RATIO OF THE SUBRETINAL FLUID IN CHOROIDAL MELANOMA AND METASTASIS.

PURPOSE: To investigate the optical density (OD) characteristics and clinical relevance of subretinal fluid in choroidal melanoma and choroidal metastasis. METHODS: Medical records of patients with choroidal melanoma and choroidal metastasis who underwent optical coherence tomography examinations at diagnosis before any intervention and whose optical coherence tomography scans showed sufficient subretinal fluid for sampling were reviewed. The highest quality B-scan containing subretinal fluid was analyzed. Optical density measurements obtained using ImageJ and optical density ratios (ODRs) were calculated as subretinal fluid OD divided by vitreous OD. Patient details and diagnosis were masked during measurements. Nonparametric tests for independent samples were used to detect differences in ODR between groups. RESULTS: Of the 39 cases of choroidal tumors that met the inclusion criteria, 14 were diagnosed as metastases and 25 as malignant melanoma. There were no significant differences between the groups in age, optical coherence tomography acquisition and parameters of quality, and vitreous OD. Optical density ratio values were significantly lower in metastases cases (mean 0.68, SD ±0.18) than in melanoma cases (0.95 ± 0.33, P = 0.006). Receiver operating characteristic curve analysis yielded an optimal cutoff of ODR = 0.771 (sensitivity = 78.6%, specificity = 72.0%). CONCLUSION: Optical density ratio can serve as an additional test to differentiate between choroidal melanoma and choroidal metastases.

Subretinal Fluid Optical Density and Spectral-Domain Optical Coherence Tomography Characteristics for the Diagnosis of Circumscribed Choroidal Hemangioma.

PURPOSE: To investigate spectral domain-optical coherence tomography (SD-OCT) features of untreated circumscribed choroidal hemangioma (CCH), and the optical density (OD) of the associated subretinal fluid (SRF). PROCEDURES: This international retrospective multicenter study conducted at 5 tertiary retina referral centers included 34 patients with symptomatic CCH imaged on SD-OCT. CCH surface, size, and overlying retinal changes and OD ratio (ODR) were evaluated. RESULTS: The mean ODR of the SRF was 0.808 ± 0.287. Tumor base measured on ultrasound correlated significantly with the ODR (p = 0.012). ODR values in cases of CCH were similar to those of choroidal metastasis, but significantly lower than those of choroidal melanoma (p = 0.006). Thirty-two out of 34 cases (94%) presented with a regular smooth choroidal surface. OCT demonstrated SRF overlying the CCH in 29 eyes (85%). The presence of SRF correlated significantly with a larger basal tumor diameter (p = 0.035). OCT displayed sub- and intraretinal hyperreflective foci, correlating with both larger maximal retinal thickness overlying the tumor (p = 0.031) and the amount of SRF (p = 0.016) in 29 eyes (85%). CONCLUSION: CCH displays typical findings on SD-OCT. ODR is a new important tool in the differential diagnosis of choroidal tumors and should be considered for enhancing the accuracy of diagnosing CCH. This benefit is especially relevant for cases in which the presentation of CCH is atypical.

The APC I1307K allele conveys a significant increased risk for cancer.

This study is the first attempt to evaluate the association between the APC I1307K variant and overall cancer risk. It is unique in both its large sample size and in the reliability of data in the control group. The findings described in this article have major implications in terms of identifying asymptomatic individuals who are at increased risk to harbor cancer and therefore targeted to be enrolled in specific early detection and prevention programs. The prevalence of the APC I1307K missense mutation among Ashkenazi Jews is ∼ 6%. Carriers are at an increased risk for colorectal neoplasia. In this study, we examined the association of this variant with non-colorectal cancers. Consecutive 13,013 healthy subjects who underwent screening at the Integrated Cancer Prevention Center between 2006 and 2014 were enrolled. This population was supplemented with 1,611 cancer patients from the same institution. Demographics, medical history, and pathological data were recorded. Mortality data were obtained from the Ministry of Health's registry. The prevalence of APC I1307K in cancer patients and healthy subjects was compared. The APC I1307K variant was detected in 189 (11.8%) cancer patients compared to 614 (4.7%) healthy subjects, reflecting an adjusted age and sex odds ratio (OR) of 2.53 (p < 0.0001). History of two or more cancer types was associated with a positive carrier prevalence (OR = 4.38 p < 0.0001). Males had significantly increased carrier prevalence in lung, urologic, pancreatic, and skin cancers. The carrier prevalence among females was significantly higher only in breast and skin cancers. Female carriers developed cancer at a significantly older age compared to non-carriers (average 62.7 years vs. 57.8, respectively, p = 0.027), had better survival rates (HR = 0.58, p = 0.022) and overall increased longevity (average age of death 78.8 vs. 70.4 years, respectively, p = 0.003). In conclusion, the APC I1307K variant is a reliable marker for overall cancer risk (OR 2.53). Further studies are needed to evaluate its use for specific cancer types-particularly in males. Female carriers have better prognosis and increased lifespan.

Ophthalmic exam and ophthalmology residents' subspecialty preference.

AIM: To evaluate residents' perceptions and attitudes toward the various aspects of a comprehensive ophthalmic examination, and to determine if these factors correlate with their choices for fellowship and future career plans. METHODS: This is a cross-sectional study. A questionnaire on the perception of the ophthalmic exam was sent via SurveyMonkey to ophthalmology residents throughout Israel. Eighty of them (one-half of all ophthalmology residents in 2019) completed it. The first part related to how they perceived each component of the ophthalmic evaluation. The second part related to their future fellowship plans. The Chi-squared test was used to compare categorical variables and Student's t-test and One-way ANOVA were used to compare continuous variables. Multivariate logistic regression analysis was applied as needed to detect interactions between variables and to exclude confounder effects. RESULTS: Slit-lamp examination of the anterior and posterior segments ranked as the most likeable aspects, whereas gonioscopy, ocular motility examination and visual acuity assessment were least likeable. Anterior segment and retina subspecialties were the ones most sought after. Forty-nine respondents (61.3%) noted a direct correlation between their preferred parts of comprehensive ophthalmic evaluations and their choice of subspecialty. Perceptions of selected components of those evaluations were significantly associated with responders' intentions to pursue anterior segment, retina, or oculoplastic fellowships (P<0.05). CONCLUSION: Perspectives of residents toward the ophthalmic examination, and most specifically its individual components, play an important role in their choice of subspecialty training.

Identifying Rapid Glaucoma Progression Using Hemifield Rates of Progression.

PRCIS: Hemifield rates of progression are more sensitive to focal progression (or faster progression) than global rates. This can aid in tailoring management and treatment decisions. PURPOSE: To determine if the rate of progression (ROP) of each hemifield of the 24-2 visual field (VF) aids in the detection of rapidly progressing eyes. METHODS: In this retrospective longitudinal study, we evaluated 1658 eyes of 1658 consecutive glaucoma patients with global mean deviation (MD) VF loss between -3 and -15 dB at baseline and ≥8 reliable VF tests (Swedish Interactive Thresholding Algorithm 24-2) with over ≥3 years of follow-up. The ROP (dB/year) based on global MD, superior hemifield MD, and inferior hemifield MD was calculated. The worst hemifield ROP (ROPworst) and hemifield ROP absolute difference (ROPdiff) were determined for each eye. Eyes were categorized based on the ROP from each metric as slow (-0.5 dB/year or better), rapid (worse than -0.5 dB/year), very rapid (worse than -1.0 dB/year), and catastrophic (worse than -2.0 dB/year) progression. The rate of significant asymmetric hemifield progression rate (ROPdiff ≥0.5 dB/year) was also evaluated. RESULTS: On average, ROPworst was faster than ROPglobal by 0.25±0.3 dB/year ( P <0.001). Based on ROPworst, 422 eyes (25%) were classified as progressing more rapidly than the ROPglobal classification. Over 40% (153/339) of the eyes classified as rapid progressors by ROPglobal were classified as very rapid or catastrophic progressors based on ROPworst. Eyes that progressed more rapidly based on ROPworst also had a higher rate of asymmetric progression. CONCLUSION: Hemifield ROPs are more sensitive to focal progression (or faster progression) than global rates and can aid in tailoring management and treatment decisions.

Glaucoma Detection Using Optical Coherence Tomography: Reviewing the Pitfalls of Comparison to Normative Data.

PRCIS: Optical coherence tomography is essential in managing glaucoma. This review describes various artifacts that originate from using a normative database to compare the individual's scans. This is a review paper regarding artifacts in optical coherence tomography imaging for glaucoma arising from using a normative database as a reference for healthy retinal nerve fiber layer and ganglion cell layer.

Understanding Patterns of Preserved Retinal Ganglion Cell Layer in Advanced Glaucoma as seen with OCT.

PRECIS: Using OCT, eyes with advanced glaucoma were found to have a wide range of patterns of damage that were consistent with the natural history of progression based upon a model of macular progression. PURPOSE: To understand the patterns of preserved retinal ganglion cells in eyes with advanced glaucoma using OCT and a model of progression of the central macula. METHODS: OCT GCL thickness was measured in 94 eyes with advanced glaucoma, defined as glaucomatous eyes with a 24-2 MD (mean deviation) worse than -12 dB. A commercial report supplied the GCL thickness in 6 sectors of the thick, donut-shaped GCL region around the fovea. For each eye, the 6 sectors were coded as green (within normal limits, WNL), yellow (≤5th, ≥1st percentile), or red (<1st percentile). RESULTS: In all 94 eyes, one or more of the 6 sectors of the donut were abnormal (red or yellow), while all 6 sectors were red in 52 (55%) of the eyes. On the other hand, 33 eyes had one or more sectors WNL (green). While the pattern of donut damage varied widely across these 33 eyes, 61 of the 66 hemiretinas were consistent with a temporal-to-nasal progression of damage within each hemiretina as predicted by our model. CONCLUSION: All eyes with advanced glaucoma had damage to the critically important central, donut-shaped GCL region. This region showed a wide range of patterns of damage, but these patterns were consistent with the natural history of progression based upon a model of macular progression. These results have implications for the clinical identification of macular progression, as well as for inclusion criteria for clinical trials seeking to preserve central macular function.

Harnessing Standing Sound Waves to Treat Intraocular Blood Cell Accumulation.

Certain ocular conditions result from the non-physiological presence of intraocular particles, leading to visual impairment and potential long-term damage. This happens when the normally clear aqueous humor becomes less transparent, thus blocking the visual axis and by intraocular pressure elevation due to blockage of the trabecular meshwork, as seen in secondary open-angle glaucoma (SOAG). Some of these "particle-related pathologies" acquire ocular conditions like pigment dispersion syndrome, pseodoexfoliation and uveitis. Others are trauma-related, such as blood cell accumulation in hyphema. While medical and surgical treatments exist for SOAG, there is a notable absence of effective preventive measures. Consequently, the prevailing clinical approach predominantly adopts a "wait and see" strategy, wherein the focus lies on managing secondary complications and offers no treatment options for particulate matter disposal. We developed a new technique utilizing standing acoustic waves to trap and direct intraocular particles. By employing acoustic trapping at nodal regions and controlled movement of the acoustic transducer, we successfully directed these particles to specific locations within the angle. Here, we demonstrate control and movement of polystyrene (PS) particles to specific locations within an in vitro eye model, as well as blood cells in porcine eyes (ex vivo). The removal of particles from certain areas can facilitate the outflow of aqueous humor (AH) and help maintain optimal intraocular pressure (IOP) levels, resulting in a non-invasive tool for preventing secondary glaucoma. Furthermore, by controlling the location of trapped particles we can hasten the clearance of the AH and improve visual acuity and quality more effectively. This study represents a significant step towards the practical application of our technique in clinical use.