Insulin resistance in the retina: possible implications for certain ocular diseases.

Insulin resistance (IR) is becoming a worldwide medical and public health challenge as an increasing prevalence of obesity and metabolic disorders. Accumulated evidence has demonstrated a strong relationship between IR and a higher incidence of several dramatically vision-threatening retinal diseases, including diabetic retinopathy, age-related macular degeneration, and glaucoma. In this review, we provide a schematic overview of the associations between IR and certain ocular diseases and further explore the possible mechanisms. Although the exact causes explaining these associations have not been fully elucidated, underlying mechanisms of oxidative stress, chronic low-grade inflammation, endothelial dysfunction and vasoconstriction, and neurodegenerative impairments may be involved. Given that IR is a modifiable risk factor, it may be important to identify patients at a high IR level with prompt treatment, which may decrease the risk of developing certain ocular diseases. Additionally, improving IR through the activation of insulin signaling pathways could become a potential therapeutic target.

[Comparative evaluation of transscleral laser exposure in anatomical experiment]. / Sravnitel'naya otsenka lazernogo transskleral'nogo vozdeistviya v usloviyakh anatomicheskogo eksperimenta.

PURPOSE: This study comparatively analyzed the morphology of eye tissues after laser exposure using the latest generation of transscleral laser techniques - micropulse transscleral cyclophotocoagulation (MP-TSCPC) and laser activation of scleral hydropermeability (LASH) - in an anatomical experiment. MATERIAL AND METHODS: The study used pulsed-periodic radiation of an Er-glass fiber laser (λ=1.56 µm) and radiation of a diode laser (λ=0.81 µm) in the micropulse mode. A comparative morphological evaluation of histological preparations of target scleral and ciliary body (CB) tissues was performed with the study of laser-induced changes occurring after LASH and MP-TSCPC. RESULTS: The study of histological preparations obtained after MP-TSCPC and LASH did not reveal any noticeable signs of an inflammatory reaction or significant destructive changes. There were no signs of pronounced coagulative changes in the form of disorganization of connective and muscle tissue in the exposure area. At the same time, MP-TSCPC was accompanied by thinning and discontinuity of the CB pigment epithelium in the projection of its flat part and expansion of the gaps between the anterior connective tissue fibers fixing the CB to the sclera, which is likely a factor contributing to uveoscleral outflow. After LASH, in the irradiated areas at the level of the outer layers of the sclera (¾ of its thickness) located in the projection of the flat part of the ciliary body, multiple slit-like cavities and enlargements (stretching) of interfiber spaces were revealed with simultaneous compaction of the inner part of the sclera (» of its thickness). CONCLUSION: The identified morphological changes may indicate certain differences in the mechanisms of intraocular pressure (IOP) reduction after MP-TSCPC and LASH. The results of this study suggest that the enhancement of uveoscleral outflow of intraocular fluid and the hypotensive effect after MP-TSCPC may be associated with laser-induced expansion of the interspaces between the anterior connective tissue fibers of the CB in the suprachoroidal space. With LASH, the possible mechanism of lowering IOP may be related rather to an increase in transscleral filtration due to the appearance of slit-like interfiber spaces in the sclera, caused by local contraction of scleral fibers in the area of laser exposure. The absence of pronounced destructive changes at the histological level indicates the gentle nature of both laser techniques and the possibility of expanding the indications for the use of LASH in the treatment of glaucoma, including at its earlier stages.

[Three-component tear substitute as preoperative support in glaucoma surgery]. / Primenenie trekhkomponentnogo slezozamenitelya v meditsinskom soprovozhdenii khirurgii glaukomy.

PURPOSE: This study investigates the effect of preoperative preparation with the three-component tear substitute Stillavit on the outcomes of glaucoma surgery in patients on long-term topical glaucoma therapy. MATERIAL AND METHODS: The study included 63 patients (63 eyes) with glaucoma, among them 30 (30 eyes) were women and 33 (33 eyes) were men. Group 1 consisted of 33 patients (33 eyes) receiving long-term topical antihypertensive therapy with preservatives and tear substitute Stillavit 3 times a day for 1 month as preoperative preparation. Group 2 included 30 patients (30 eyes) receiving similar antihypertensive therapy who were not prescribed preoperative medications. All patients underwent a comprehensive ophthalmological examination and computer tomography of the filtering blebs (FB) on Visante system (Carl Zeiss Meditec, Germany) before surgery, as well as 1 week, 1, 3, and 6 months after surgery. RESULTS: Mean intraocular pressure (IOP) elevation at 6 months postoperatively was significantly higher in the group that did not undergo preoperative preparation with a tear substitute, compared to the group of patients who received the tear substitute Stillavit preoperatively. According to anterior segment optical coherence tomography, a greater number of favorable diffuse FB were noted in the group that received the tear substitute Stillavit in preparation for surgery - 87.9%, while in group 2 (without preparation) - 66.7%. Odds ratio calculation between the two groups revealed that preoperative preparation with the tear substitute Stillavit reduced the odds of IOP elevation to 20 mm Hg or higher at 3 months postoperatively by more than 10 times. CONCLUSION: The use of tear substitute Stillavit in preparation for anti-glaucoma surgery reduces the chances of IOP elevation in the early postoperative period by more than 10 times, which may indicate a reduction in the rate of FB scarring due to the beneficial effect of the drug's components on the precorneal tear film.

[First experience of implantation of extended depth of focus intraocular lenses in patients with glaucoma]. / Pervyi opyt implantatsii intraokulyarnykh linz s uvelichennoi glubinoi fokusa u patsientov s glaukomoi.

PURPOSE: This study evaluates the effectiveness of implantation of extended depth of focus (EDOF) intraocular lenses (IOL) in patients with cataract and glaucoma. MATERIAL AND METHODS: The study included 13 patients (16 eyes) who underwent implantation of the Lentis Comfort EDOF IOL (Teleon Surgical BV, Netherlands). Standard phacoemulsification cataract surgery with IOL implantation was performed in a planned manner after the hypotensive surgery stage in two eyes; a combined procedure was performed in 14 cases. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), near visual acuity, and intraocular pressure (IOP) measured with a Maklakov tonometer were assessed preoperatively, on the first day, and 3-6 months after surgery. Computer perimetry using the 30-2 program and spatial contrast sensitivity (SCS) assessment were also performed preoperatively and at the same follow-up time points. RESULTS: On the first day after surgery, UCVA was 0.53±0.65, BCVA was 0.85±0.45. Near UCVA (at 40 cm) was 0.5±0.14 on the first day after surgery and 0.56±0.18 at 3-6 months. According to computer perimetry data, retinal light sensitivity values increased in all patients in the long-term (-3.1±2.9 dB). SCS values increased for objects of all sizes compared to preoperative values. CONCLUSION: Implantation of EDOF IOL contributes to improved vision without reducing contrast sensitivity and retinal light sensitivity in patients with concomitant cataract and glaucoma.

[Possibilities of physiotherapy in glaucomatous optic neuropathy after glaucoma surgery]. / Vozmozhnosti fizioterapevticheskoi stimulyatsii pri glaukomnoi opticheskoi neiropatii posle antiglaukomnykh operatsii.

The current primary approach to the therapeutic and surgical management of glaucoma is limited to lowering intraocular pressure (IOP). While normalization of IOP stabilizes some functional parameters, there is still potential for further restoration of lost visual function in the post-operative period while maintaining the "therapeutic window". Neuroprotection refers to the modification of retinal ganglion cells and the neuronal microenvironment to promote their survival and function. Numerous studies have identified effective neuroprotective methods for glaucoma; however, their implementation into clinical practice remains a significant challenge. This review presents the most clinically significant treatment strategies, as well as the latest therapeutic advances in physiotherapy.

Accuracy of a novel method for IOP measurement without applying pressure on the cornea.

PURPOSE: To assess the accuracy of a prototype novel instrument for intra ocular pressure (IOP) measurements not involving corneal pressure application. DESIGN: Prospective case control study. METHODS: An institutional study including 16 healthy volunteers without ocular pathology. IOP in both eyes of the participants was measured four times in different body positions with the novel prototype and reference instrument (Goldmann applanation tonometer (GAT) or iCare (iCare Finland OY, Vantaa, Finland)). IOP results were compared between the prototype and the reference instruments in 116 pairs of measurement. RESULTS: Overall no statistically significant difference was found between the presented prototype and the reference instrument. Stratifying measurements by instrument used revealed no significant difference for GAT and statistical significant (yet clinically insignificant) difference for iCare. CONCLUSIONS: The presented prototype demonstrates good clinical agreement of IOP measuring results with reference instruments Further large-scale studies assessing this instrument in glaucoma patients are warranted.

Contributions of Brain Microstructures and Metabolism to Visual Field Loss Patterns in Glaucoma Using Archetypal and Information Gain Analyses.

Purpose: To investigate the contributions of the microstructural and metabolic brain environment to glaucoma and their association with visual field (VF) loss patterns by using advanced diffusion magnetic resonance imaging (dMRI), proton magnetic resonance spectroscopy (MRS), and clinical ophthalmic measures. Methods: Sixty-nine glaucoma and healthy subjects underwent dMRI and/or MRS at 3 Tesla. Ophthalmic data were collected from VF perimetry and optical coherence tomography. dMRI parameters of microstructural integrity in the optic radiation and MRS-derived neurochemical levels in the visual cortex were compared among early glaucoma, advanced glaucoma, and healthy controls. Multivariate regression was used to correlate neuroimaging metrics with 16 archetypal VF loss patterns. We also ranked neuroimaging, ophthalmic, and demographic attributes in terms of their information gain to determine their importance to glaucoma. Results: In dMRI, decreasing fractional anisotropy, radial kurtosis, and tortuosity and increasing radial diffusivity correlated with greater overall VF loss bilaterally. Regionally, decreasing intra-axonal space and extra-axonal space diffusivities correlated with greater VF loss in the superior-altitudinal area of the right eye and the inferior-altitudinal area of the left eye. In MRS, both early and advanced glaucoma patients had lower gamma-aminobutyric acid (GABA), glutamate, and choline levels than healthy controls. GABA appeared to associate more with superonasal VF loss, and glutamate and choline more with inferior VF loss. Choline ranked third for importance to early glaucoma, whereas radial kurtosis and GABA ranked fourth and fifth for advanced glaucoma. Conclusions: Our findings highlight the importance of non-invasive neuroimaging biomarkers and analytical modeling for unveiling glaucomatous neurodegeneration and how they reflect complementary VF loss patterns.

Role of T cell-induced autoimmune response in the pathogenesis of glaucoma.

PURPOSE: This review aims to elucidate the role of T cell-induced autoimmune responses in the pathogenesis of glaucoma, focusing on the immunological changes contributing to retinal ganglion cell (RGC) damage. METHODS: A comprehensive review of recent studies examining immunological mechanisms in glaucoma was conducted. This included analyses of T cell interactions, heat shock proteins (HSPs), and resultant autoimmune responses. Key findings from experimental models and clinical observations were synthesized to present a coherent understanding of immune dynamics in glaucoma. RESULTS: Glaucoma is a neurodegenerative disease marked by optic nerve atrophy and irreversible vision loss due to RGC damage. The disease is etiologically heterogeneous, with multiple risk factors and pathogenic mechanisms. Recent research highlights the dual immunomodulatory role of T cells in immune protection and injury. T cells, pre-sensitized by bacterial HSPs, can cross-react with endogenous HSPs in RGCs under stress, leading to autoimmune damage. Elevated levels of HSP autoantibodies and abnormal T cell activity have been observed in glaucoma patients, indicating a significant autoimmune component in disease progression. CONCLUSIONS: T cell-induced autoimmune responses are crucial in the pathogenesis of glaucoma, contributing to RGC degeneration beyond the effects of elevated intraocular pressure. Understanding these immunological mechanisms is vital for developing targeted neuroprotective therapies for glaucoma.

An eternal hunt for glaucoma.

In the first issue of Graefe's Archive from 1854, Albrecht von Graefe wrote about glaucoma. Glaucoma comes from the Greek word "glaukos," gleaming, which was first used by Homer around 800 BCE. Since then, glaukos and glaucoma have taken on many different meanings. The terms blindness, cataract and glaucoma were used interchangeably and twisted together in incomprehensible contexts. Over 2500 years of glaucoma theories were upset by the discovery of the ophthalmoscope in 1851. The first reports of increased intraocular pressure appeared in the mid-seventeenth century, but it took over 200 years for this elevated pressure to be accepted by the ophthalmological community. The discovery of glaucoma simplex in 1861 was an important step forward. What did doctors know about glaucoma before 1850 and why did it take so long to classify glaucoma in its various categories? And why is it that we still do not know what the cause is for primary open angle glaucoma? I will try to answer some of these questions after a historical overview.

Intraoperative challenges and outcomes of pediatric cataract surgery following glaucoma filtering surgery.

PURPOSE: To analyze the intraoperative challenges of cataract surgery in children, following glaucoma filtering surgery. METHODS: This was a retrospective study to analyze intra-op challenges and outcomes of pediatric cataract surgery in post-glaucoma filtration surgery eyes, between January 2007 and December 2019. RESULTS: We included 20 eyes of 16 children. The most common glaucoma surgery performed was trabeculectomy and trabeculotomy (14 eyes). The median age at the time of cataract surgery was 74.5 months. The most common cataract surgery performed was lens aspiration with posterior chamber intraocular lens implantation (LA + PCIOL) (9/20). The most common intraoperative challenge faced was difficulty in capsulorrhexis (ten eyes), followed by extension of primary posterior capsulotomy (six eyes). At the final follow up eight eyes had improvement in visual acuity, five eyes had stable visual acuity and five eyes had a drop in visual acuity. In 12/20 eyes IOL was implanted, nine eyes in-the-bag and three eyes had in ciliary sulcus. None of the IOLs in the bag had decentration of IOL. The median postoperative IOP (p = 0.12) and median number of postoperative AGM (p = 0.13) at 2 years remained stable compared to the preoperative values. The IOP remained well controlled in 4 eyes without anti-glaucoma medications and in 14 eyes with anti-glaucoma medications and none needed additional surgery for IOP control. Two eyes developed retinal detachment postoperatively. CONCLUSION: Cataract surgery in pediatric eyes with prior glaucoma surgeries, have challenges with capsulorrhexis and IOL stability. The visual outcomes were reasonably good so was the IOP control.

Agreement of tonometer for measuring intraocular pressure in Wistar rats: a systematic review.

Glaucoma is the most common cause of irreversible blindness in the world. It is associated with elevated intraocular pressure (IOP). Fluctuations in tonometer readings have implications for glaucoma research, where accurate IOP measurements are vital for evaluating disease progression and treatment efficacy. Researchers should carefully select the appropriate tonometer and consider biases associated with different tonometers. Validation against standard measurements can improve IOP measurement accuracy in rat models. In conclusion, this systematic review will emphasize on the importance of selecting the appropriate tonometer for IOP measurement in rat models, considering potential biases and their implications for glaucoma research. Accurate and consistent IOP measurement in rat models is crucial for understanding glaucoma pathophysiology and developing effective treatments. This systematic review aims to assess agreement among tonometers used for measuring IOP in Wistar rat models primarily focusing on TonoLab, TonoVet, and Tono-pen. The review was conducted using PRISMA guidelines. Two articles were included for qualitative synthesis. The studies compared manometric IOP with TonoLab, rebound tonometer, and Tono-pen XL readings. It was observed that TonoLab consistently underestimated IOP, while Tono-pen XL tended to overestimate IOP compared to manometric measurements. The study's findings will help researchers in making decisions about tonometer selection, leading to more reliable outcomes in glaucoma research using rat models. Further research, specifically RCT's (randomized controlled trial) is needed to confirm the results and enhance IOP measurement precision in rat models.

Applicability of Oculomics for Individual Risk Prediction: Repeatability and Robustness of Retinal Fractal Dimension Using DART and AutoMorph.

Purpose: To investigate whether fractal dimension (FD)-based oculomics could be used for individual risk prediction by evaluating repeatability and robustness. Methods: We used two datasets: "Caledonia," healthy adults imaged multiple times in quick succession for research (26 subjects, 39 eyes, 377 color fundus images), and GRAPE, glaucoma patients with baseline and follow-up visits (106 subjects, 196 eyes, 392 images). Mean follow-up time was 18.3 months in GRAPE; thus it provides a pessimistic lower bound because vasculature could change. FD was computed with DART and AutoMorph. Image quality was assessed with QuickQual, but no images were initially excluded. Pearson, Spearman, and intraclass correlation (ICC) were used for population-level repeatability. For individual-level repeatability, we introduce measurement noise parameter λ, which is within-eye standard deviation (SD) of FD measurements in units of between-eyes SD. Results: In Caledonia, ICC was 0.8153 for DART and 0.5779 for AutoMorph, Pearson/Spearman correlation (first and last image) 0.7857/0.7824 for DART, and 0.3933/0.6253 for AutoMorph. In GRAPE, Pearson/Spearman correlation (first and next visit) was 0.7479/0.7474 for DART, and 0.7109/0.7208 for AutoMorph (all P < 0.0001). Median λ in Caledonia without exclusions was 3.55% for DART and 12.65% for AutoMorph and improved to up to 1.67% and 6.64% with quality-based exclusions, respectively. Quality exclusions primarily mitigated large outliers. Worst quality in an eye correlated strongly with λ (Pearson 0.5350-0.7550, depending on dataset and method, all P < 0.0001). Conclusions: Repeatability was sufficient for individual-level predictions in heterogeneous populations. DART performed better on all metrics and might be able to detect small, longitudinal changes, highlighting the potential of robust methods.

The effect of cumulative energy in repeated subliminal transscleral cyclophotocoagulation: a retrospective study.

BACKGROUND: The long-term safety and efficacy of repeated applications of subliminal transscleral cyclophotocoagulation (SL-TSCPC) with a focus on cumulative energy was evaluated in glaucoma patients. METHODS: In this retrospective, multicentric study the data of a total of 82 eyes with various causes of glaucoma that were treated with a single or multiple applications of SL-TSCPC were collected. Treatments were performed under general or local anesthesia with an 810 nm diode laser. Power was 2000 mW; duty cycle, 31.3%; total treatment duration, 80-320 s; equaling a total energy of 50-200 J per treatment session. Fifty-five eyes (55 patients) presented for all follow-ups, and these eyes were selected for further statistical analysis. The mean age was 60.0 ± 17.1 years, and 22 (40%) of the patients were female. Intraocular pressure (IOP) and dependence on further glaucoma medication were evaluated at 12 months following the initial treatment. RESULTS: Eyes underwent 1 or 2 consecutive SL-TSCPC treatments. Median (min-max) baseline IOP of 34 (13-69) decreased to 21.5 (7-61), 22 (8-68), 20 (9-68), and 19.5 (3-60) mmHg at the 1, 3, 6, and 12-month postoperative timepoints respectively. The mean (± SD) IOP decrease at 12 months was 26 ± 27%, 39 ± 32%, and 49 ± 33% in the low (below 120 J, n = 18), medium (120-200 J, n = 24), and high (above 200 J, n = 13) cumulative energy groups respectively. At the 12-month timepoint, oral carbonic anhydrase use was discontinued in ¾ of the cases. CONCLUSIONS: It was found that the repeated application of SL-TSCPC safely and efficiently decreases IOP in a Caucasian population with heterogenous causes of glaucoma, eyes with silicone oil responded to a greater extent. Inclusion of cumulative energy scales may contribute to better addressing repeated procedures in a standardized fashion.

The Ocular Glymphatic System-Current Understanding and Future Perspectives.

The ocular glymphatic system subserves the bidirectional polarized fluid transport in the optic nerve, whereby cerebrospinal fluid from the brain is directed along periarterial spaces towards the eye, and fluid from the retina is directed along perivenous spaces following upon its axonal transport across the glial lamina. Fluid homeostasis and waste removal are vital for retinal function, making the ocular glymphatic fluid pathway a potential route for targeted manipulation to combat blinding ocular diseases such as age-related macular degeneration, diabetic retinopathy, and glaucoma. Several lines of work investigating the bidirectional ocular glymphatic transport with varying methodologies have developed diverging mechanistic models, which has created some confusion about how ocular glymphatic transport should be defined. In this review, we provide a comprehensive summary of the current understanding of the ocular glymphatic system, aiming to address misconceptions and foster a cohesive understanding of the topic.

Evaluation of machine learning approach for surgical results of Ahmed valve implantation in patients with glaucoma.

BACKGROUND: Ahmed valve implantation demonstrated an increasing proportion in glaucoma surgery, but predicting the successful maintenance of target intraocular pressure remains a challenging task. This study aimed to evaluate the performance of machine learning (ML) in predicting surgical outcomes after Ahmed valve implantation and to assess potential risk factors associated with surgical failure to contribute to improving the success rate. METHODS: This study used preoperative data of patients who underwent Ahmed valve implantation from 2017 to 2021 at Ajou University Hospital. These datasets included demographic and ophthalmic parameters (dataset A), systemic medical records excluding psychiatric records (dataset B), and psychiatric medications (dataset C). Logistic regression, extreme gradient boosting (XGBoost), and support vector machines were first evaluated using only dataset A. The algorithm with the best performance was selected based on the area under the receiver operating characteristics curve (AUROC). Finally, three additional prediction models were developed using the best performance algorithm, incorporating combinations of multiple datasets to predict surgical outcomes at 1 year. RESULTS: Among 153 eyes of 133 patients, 131 (85.6%) and 22 (14.4%) eyes were categorized as the success and failure groups, respectively. The XGBoost was shown as the best-performance model with an AUROC value of 0.684, using only dataset A. The final three further prediction models were developed based on the combination of multiple datasets using the XGBoost model. All datasets combinations demonstrated the best performances in terms of AUROC (dataset A + B: 0.782; A + C: 0.773; A + B + C: 0.801). Furthermore, advancing age was a risk factor associated with a higher surgical failure incidence. CONCLUSIONS: ML provides some predictive value in predicting the outcomes of Ahmed valve implantation at 1 year. ML evaluation revealed advancing age as a common risk factor for surgical failure.

Concurrent ciliary body detachment in patients presenting with serous choroidal detachment following glaucoma surgery.

PURPOSE: To examine the rate of ciliary body detachment in patients with choroidal detachment following glaucoma surgery and its effect on the clinical course, management, and prognosis. METHODS: A prospective observational case-series study. Patients with choroidal detachment following glaucoma surgery in 2018-2019 were included. All underwent complete ophthalmological examination and ultrasound biomicroscopy for evaluation of the presence and extent of ciliary body detachment. Follow-up examinations including ultrasound biomicroscopy scans were performed at 1 week, 1 month, 3 months, and 6 months. RESULTS: Eight patients (8 eyes) were enrolled, 4 male and 4 female, of mean age 72 years (range 60-83). Five patients underwent trabeculectomy with mitomycin C (0.02%), which was combined with phacoemulsification cataract extraction in one; two underwent Ahmed glaucoma valve implantations, and one underwent ab-interno Xen45 gel stent implantation with mitomycin C (0.02%). The mean intraocular pressure was 26.0 ± 7.65 mmHg preoperatively, dropping to 6.9 ± 2.64 mmHg on first postoperative day one. Mean time from surgery to diagnosis of choroidal detachment was 11.6 ± 5.73 days. Ciliary body detachment was identified by ultrasound biomicroscopy in all patients, ranging between one and four quadrants. All patients were treated with topical steroids and cycloplegics; three (37.5%) received oral steroids. No surgical intervention for the choroidal or ciliary body detachments was indicated. CONCLUSIONS: In this real-world prospective study, concurrent ciliary body detachment was identified in all patients who presented with choroidal detachment following glaucoma surgery. This observation may deepen our understanding of the mechanism underlying the hypotony that is often seen after glaucoma surgery.

Evaluation of lamina cribrosa curvature index in different types of glaucoma.

OBJECTIVE: The aim of this study was to evaluate the lamina cribrosa curvature index in different types of glaucoma in comparison with clinical findings and conventional measurement methods. MATERIAL AND METHOD: Patients older than 18 years who were followed up in Glaucoma Unit of Department of Ophthalmology at Firat University Faculty of Medicine, whose disease had been under control at least for 1 year, who had at least three reliable visual fields, whose refractive error was between - 6 and + 5 diopter and who did not have any disease other than glaucoma that would affect the visual field, were included in the study. Clinical and demographic characteristics, visual field, optical coherence tomography and lamina cribrosa curvature index (LCCI) results were evaluated. The study patients were divided into six groups: early-stage primary open-angle glaucoma (POAG) as group 1 and intermediate-advanced stage POAG as group 2, pseudo-exfoliation glaucoma (PEXG) as group 3, normal tension glaucoma (NTG) as group 4, ocular hypertension patients whom subsequently developed POAG as group 5 and healthy control as group 6. RESULTS: A total of 189 eyes of 101 patients were included in our study. Forty-seven patients were male (46.5%) and 54 were female (53.5%). The mean age was 62.43 ± 1.49 years. LCCI, mean deviation (MD), visual field index (VFI), pattern standard deviation (PSD) and retinal nerve fiber layer thickness (RNFL) values were analyzed in all groups and Pearson correlation analysis showed statistically significant correlation between PSD and RNFL measurements with LCCI values in all groups. MD value was correlated with LCCI in groups 2, 3 and 4, while VFI value was correlated with LCCI in all groups except group 5. When the groups were compared with each other according to the Post-Hoc Tamhane test, LCCI measurement showed statistically significant results in accordance with MD, VFI, PSD and RNFL values. CONCLUSION: The LCCI assessment is mostly consistent with conventional tests. In this study, in which different types of glaucoma and healthy subjects were examined simultaneously, LCCI shows promise as a detailed and reliable assessment method.

Exploring the Feasibility of Estimating Intraocular Pressure Using Vibrational Response of the Eye: A Methodological Approach.

This study addresses the limitations of current tonometry techniques by exploring vibroacoustic properties for estimating intraocular pressure (IOP), a key diagnostic parameter for monitoring glaucoma-a significant risk factor for vision loss. Utilizing vivo porcine eyeballs, we investigated the relationship between IOP and the nonlinear vibration transfer function ratio (NVTFR). Through applying varying vibration levels and analyzing responses with transfer function analysis and univariate regression, we identified a strong negative correlation between NVTFR and IOP, evidenced by a Pearson correlation coefficient of -0.8111 and significant results from generalized linear model (GLM) regression (p-value < 0.001). These findings indicate the potential of NVTFR as a vital indicator of IOP changes. Our study highlights the feasibility of using vibroacoustic properties, specifically NVTFR, to measure IOP. While further refinement is necessary for in vivo application, this approach opens new possibilities for non-invasive and patient-friendly IOP monitoring, potentially enhancing ophthalmology diagnostic techniques and providing a foundation for future research and development in this critical area.

Healing responses at the angle after micro-invasive glaucoma surgery-an AS-OCT study.

PURPOSE: To evaluate structural alterations and healing responses in the trabecular meshwork region with optical coherence tomography (AS-OCT) following after gonioscopy assisted transluminal trabeculotomy (GATT) and microincisional trabeculectomy (MIT). METHODS: 73 eyes of 67 patients (M:F = 45:22) with ≥6 months of follow-up after MIT (n = 41) or GATT (n = 32) with or without combined cataract surgery were included for this prospective study. The angle as seen on AS-OCT at 1, 3, 6 months after surgery were evaluated for structural alterations like peripheral anterior synechiae (PAS), hyphema, and hyperreflective scarring responses. The scarring was graded according to the linear extent measured from the centre of the trabecular meshwork (TM) gutter to the sclera/cornea as mild (<250µ), moderate (250-500µ), and severe(˃500µ), while the pattern of scarring was graded as open saucer/gutter, closed gutter, and trench pattern. The association of the need for medication or surgical outcome and clinical variables and AS-OCT parameters including the pattern and severity of scarring were analysed using multivariate regression. RESULTS: All eyes achieved significant reduction of IOP and number of medications with a final IOP of 15±3.2mm Hg at a mean follow-up of 8±32. months. While mild scarring was seen more common in MIT, severe scarring was seen in >65% of GATT eyes compared to 31% of MIT eye, p<0.001. An open saucer was equally seen in MIT and GATT while the trench pattern was more commonly seen in GATT eyes (>50%). Severe scarring in a trench pattern seemed to predict the need for medications for IOP control, though they independently did not seem to influence the final IOP or surgical outcome. CONCLUSION: A severe form of scarring in a trench pattern on AS-OCT predicted the need for glaucoma medications after MIGS surgery. Regular monitoring of the scarring responses by AS-OCT and clinical examination are necessary to identify those at need for medications after MIGS.

A comparison of iCare and Goldmann applanation tonometry measurements during the COVID-19 pandemic: a retrospective study.

PURPOSE: To evaluate factors associated with differences in intraocular pressure (IOP) readings between iCare and Goldmann applanation tonometry (GAT) in established glaucoma patients. METHODS: This retrospective comparative study included clinical data of 350 eyes from 350 established glaucoma patients who had iCare and GAT IOP measured by an ophthalmic technician and a glaucoma specialist, respectively. The main outcome measure was the difference in IOP measurements of the right eyes with iCare and GAT. RESULTS: The intraclass correlation coefficient (ICC) between GAT and iCare was 0.90. The mean IOP difference between tonometers was - 0.18 ± 2.89 mmHg. Bland-Altman plots indicated a 95% limit of agreement of - 5.8 to 5.5 mmHg. Central corneal thickness (CCT) and age were significantly correlated with the difference in IOPs of the iCare and GAT. GAT-IOP and age were significantly associated with the absolute difference in measured IOP of the two tonometers. The difference in measurements was not significantly associated with prior glaucoma surgery, average global index of optical coherence tomography, axial length, technician years of experience and certification, and IOP range. CONCLUSION: Although there is good agreement between the iCare and GAT mean values, these devices are not interchangeable in glaucoma patients due to the wide range of the limit of agreement.