Ganglion Cell Complex Research Articles

Clinical and Structural Parameters in Autosomal Dominant Optic Atrophy Patients: A Cross-Sectional Study Using Optical Coherence Tomography

Background: Autosomal Dominant Optic Atrophy (ADOA) is a hereditary optic neuropathy characterized by retinal ganglion cell degeneration and optic nerve fiber loss. This study examined the correlation between clinical and structural parameters in patients with ADOA using optical coherence tomography (OCT) and explored potential clinical biomarkers. Methods: A cross-sectional, case–control observational study included 27 patients with ADOA and 27 age- and sex-matched healthy controls. Clinical examinations, OCT imaging, and OCT angiography (OCTA) were performed. Statistical analyses were conducted to establish correlations between clinical and OCT parameters. Results: Patients with ADOA exhibited gradual bilateral vision loss, central scotomas, and optic disc pallor. Structural OCT analysis revealed significant reductions in central macular thickness, macular volume, ganglion cell complex (GCC), and peripapillary retinal nerve fiber layer compared with controls. Correlation analysis demonstrated associations between worsening clinical parameters (best corrected visual acuity, Sloan Letters Low Contrast Chart 25%, Pseudoisochromatic Test) and increased OCT damage (structural and OCTA). GCC emerged, at least at exploratory terms, as the most important clinical biomarker in patients with ADOA given its multiple positive functional associations, while OCTA parameters correlated with visual field defects. Conclusions: Our study revealed significant correlations between clinical and structural parameters in patients with ADOA, highlighting the importance of OCT in assessing disease severity. GCC measurement shows promise as a clinical biomarker, aiding in disease monitoring. OCTA parameters offer potential early biomarkers for vascular changes. These findings contribute to understanding ADOA pathophysiology and may improve patient diagnosis and management. Further research is warranted to validate these findings and explore potential therapeutic interventions.

Choroidal and retinal alteration after long-term use of tadalafil: a prospective non-randomized clinical trial.

The purpose of this study is to investigate choroidal and retinal vascular features in patients taking PDE5is by measuring dynamic vascular alterations and neurostructural features of the retina before and after oral tadalafil administration. The current clinical research involved 22 patients treated with tadalafil 20 mg on alternate days (OAD) after nerve-sparing robotic radical prostatectomy (NS-RARP) for prostate cancer. Patients underwent SD-OCT to assess ganglion cell complex (GCC), retinal nerve fiber layer (RNFL), and subfoveal choroidal thickness (SFCT), as well as OCTA to assess superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris (CC), foveal avascular zone (FAZ), and radial peripapillary capillary thickness (RPC). All patients were evaluated at baseline (t0), and 3 (t1) and 6 (t2) months after the use of oral tadalafil. A statistically significant reduction in DCP and CC vessel density was found at t2 compared to baseline. According to the SFCT parameter, a statistically significant increase was observed from t0 to t1, and from t1 to t2. GCC parameter increased at t2 compared to baseline in a statistically significant way. No statistically significant differences were recorded between t0, t1 and t2 for the SCP, RPC, FAZ area, RNFL parameter. Retinal and optic disc toxicity may be detected using modifications of capillary vessel density. Further studies are needed to detect the possible progression or regression of ocular or systemic vascular complications in long-term follow-up.

Examination of optical coherence tomography findings in patients with pregabalin use disorder.

Pregabalin abuse is a rapidly growing health problem worldwide, and little is known about the effects of prolonged high-dose use in patients with pregabalin use disorder. In this study, the effects of pregabalin abuse on retinal layers were investigated in patients with pregabalin use disorder (PGUD). This study included 35 controls and 34 patients with PGUD, according to Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 criteria. Optic coherence tomography (OCT) measurements including the retinal nerve fiber layer (RNFL), ganglion cell layer-inner plexiform layer (GCL-IPL) and ganglion cell complex (GCC) were performed. RNFL thickness was evaluated in four quadrants (inferior, superior, nasal, temporal). GCL-IPL and GCC thickness were evaluated in six sectors (superior, superonasal, inferonasal, inferior, inferotemporal, superotemporal). GCC inferonasal (p = 0.040, r = 0.354), GCC inferior (p = 0.018, r = 0.402) GCL-IPL inferior (p = 0.031, r = 0.370) and GCL-IPL inferotemporal (p = 0.029, r = 0.376) thickness were positively correlated with the duration of pregabalin use. There was no significant sector or quadrant-wise difference between groups (p > 0.05). Our findings emphasized the drug's potential neuroprotective effect. It should be taken into consideration that neurodegenerative changes due to substance use disorder occur with long-term. Longitudinal prospective studies investigating dose-duration relationship are needed.

Effect of enhanced monofocal intraocular lenses on glaucoma patients' foveal threshold.

We investigated the effect of enhanced monofocal intraocular lenses (IOL) (TECNIS Eyhance DIB00V) on retinal sensitivity in glaucoma patients after cataract surgery by comparing results with of such patients implanted with non-enhanced monofocal intraocular lenses (TECNIS ZCB00V). This was a multi-facility retrospective study of glaucoma patients who had undergone cataract surgery. We measured the value of the foveal threshold with a Humphrey visual field analyzer before and after cataract surgery and considered this value to represent the sensitivity of the retina. As a sub-analysis, we also compared the mean deviation (MD), pattern standard deviation (PSD), thickness of ganglion cell complex (GCC), and best corrected visual acuity (BCVA) before and after surgery. We used t-tests to determine statistical differences between lens groups. We included 60 glaucoma patients (104 eyes) who underwent cataract surgery: enhanced group, n = 58 eyes; non-enhanced group, n = 46 eyes. In both groups, cataract surgery improved the retinal sensitivity (p < 0.001), MD (p < 0.001) and BCVA (p < 0.001). The postoperative foveal thresholds did not significantly differ by lens type (p = 0.673), at 34.41 ± 2.44dB in the enhanced group and 34.61 ± 2.19dB in the non-enhanced group. Likewise, there was no significant difference (p = 0.942) among advanced glaucoma patients, with postoperative foveal thresholds of 33.08 ± 2.35dB and 33.17 ± 3.45dB in the enhanced and non-enhanced, respectively. Implantation of enhanced monofocal IOLs in glaucoma patients did not result in any apparent loss of sensitivity compared with non-enhanced monofocal lens implantation.

Optical coherence tomography angiography of peripapillary vessel density in non-arteritic anterior ischemic optic neuropathy and demyelinating optic neuritis.

In cases of optic disc edema or a pale optic disc, distinguishing an episode of optic neuritis (ON) from that of non-arteritic anterior ischemic optic neuropathy (NAION) during a clinical examination is challenging. Optical coherence tomography angiography (OCTA) can reveal differences in peripapillary vascular network structures and provide biomarkers for differential diagnosis. A total of 23 eyes with NAION, 22 eyes with demyelinating ON (DON), and 27 eyes from healthy participants were imaged using OCTA to observe the radial peripapillary capillaries (RPCs). Optical coherence tomography was used to measure peripapillary retinal nerve fiber layer (RNFL) thickness and the macular ganglion cell complex (mGCC). Data for all patients were recorded at 2-3 weeks and more than 3 months after the symptom onset. A total of 23 affected eyes from 23 patients with NAION (average age 52.17 ± 7.92 years), 22 eyes from 22 patients with demyelinating optic neuritis (DON) (average age 47.88 ± 19.24 years), and 27 eyes from 27 healthy individuals (average age 46.43 ± 14.08 years) were included in the study. There were no significant differences in sex, age, and eye laterality between any two groups (F = 0.968, 0.475, 0.870; p > 0.05). Throughout the course of NAION and DON, the superior RPC, superior mGCC, and peripapillary RNFL decreased with time (p < 0.05). In contrast, the inferotemporal RPC and inferior mGCC did not decrease from the acute to chronic stage in NAION (t = 1.639, 0.834, p = 0.117, 0.413). Compared with the normal group, patients with NAION and DON exhibited a sharp reduction in the average RPC, RNFL, and GCC from the acute to the chronic stage (p < 0.05). Patients with DON exhibited a significant decrease in the inferotemporal RPC and inferior mGCC compared with the patients with NAION (p < 0.05). In contrast, there were no significant differences in the inferior mGCC at the chronic stage between the patients with NAION and those with ON (t = 2.547, p = 0.093). Various structural and microvascular changes were observed in patients with NAION and ON, indicating distinct features of the optic nerve during the different stages of NAION and ON. Peripapillary vascular density, measured using spectral domain OCT (SD-OCT), may be a biomarker to distinguish NAION from ON.

Monitoring of several morphometric parameters of the optic nerve and retina in persons without glaucoma and patients with primary open-angle glaucoma using various types of spectacle correction

Purpose: to perform long-term monitoring of the state of several morphometric parameters of the retina and optic nerve in persons without glaucoma and patients with primary open-angle glaucoma (POAG) in the conditions of achieving tolerant and target IOP against the background of the use of various types of spectacle correction. Material and methods: 139 patients aged 40–60 years with various types of clinical refraction were examined, 41 subjects (81 eyes) of them were without glaucoma, 98 patients (164 eyes) had POAG at stage I–II. In addition to standard methods, the scope of the examination included optical coherence tomography (OCT) of the optic nerve and the central area of the retina to determine the thickness of the retinal nerve fiber layer (RNFL), retinal ganglion cell complex (RGCC) and the area of the neuroretinal rim (NRR). The study was conducted in 4 observation groups. The first (21subjects) and the second (20 subjects) groups were represented by persons without glaucoma who used monofocal spectacle correction and progressive spectacle correction for near work, respectively. The third (50 subjects) and the fourth (48 subjects) groups were composed of patients with POAG who also used, respectively, monofocal spectacle correction for near vision or progressive spectacle correction against the background of topical hypotensive therapy with the achievement of tolerant and target IOP. The follow-up period was three years. Results: There were no significant changes in the area of NRR (p 0,5) and in the thickness of RNFL (p 0,2) and RGCC (p 0,3) over the three-year follow-up period in all patients without glaucoma. In patients with POAG who applied progressive correction, no negative dynamics was revealed in the NRR area (p 0,5) and in the thickness of RNFL (p 0,5) and RGCC (p 0,5) during the follow-up period. POAG patients with using monofocal correction had noticeable losses in RNFL and RGCC thickness (p 0,05) without a significant decrease in the area of NRR (p 0,3). Conclusion: The progressive spectacle correction using provides accommodative regulation of IOP in POAG and implements an indirect neuroprotective effect.

Application of optical coherence tomography in neurodegenerative diseases: a focus on Parkinson’s, Alzheimer’s, and Schizophrenia in Bulgarian patients

This study investigates retinal alterations in patients with Alzheimer’s disease (AD), Parkinson’s disease (PD), and schizophrenia (SZ) using Optical Coherence Tomography (OCT). The primary objective was to determine whether these neurodegenerative diseases manifest in measurable retinal changes and to assess the impact of disease duration, medication use, and cognitive decline on these alterations. A cross-sectional observational design was employed, including 132 patients and age- and gender-matched controls. OCT imaging was performed using the Topcon 3D OCT-1 Maestro 2, focusing on the retinal nerve fibre layer (RNFL), ganglion cell complex (GCC), and macular thickness. Significant retinal thinning was observed in the AD and PD groups, correlating with disease severity and cognitive decline, and was more pronounced with longer disease duration. In contrast, no significant retinal changes were identified in the SZ group. The study also explored the effects of different drug classes, revealing correlations between specific medications and retinal parameters, particularly in the AD and PD cohorts. To our knowledge, this is the first study of its kind conducted with Bulgarian patients. These findings suggest that OCT may serve as a non-invasive biomarker for neurodegeneration in AD and PD, though its utility in SZ remains limited. Future research should aim to standardize OCT protocols, further investigate the potential of retinal imaging in tracking neurodegenerative disease progression, and explore its integration with other neuroimaging techniques for a more comprehensive diagnostic and monitoring approach.

Diagnostic Performance for Detection of Glaucomatous Structural Damage Using Pixelwise Analysis of Retinal Thickness Measurements.

To compare the diagnostic accuracy of thickness measurements of individual and combined macular retinal layers to discriminate 188 glaucomatous and 148 glaucoma suspect eyes from 362 healthy control (HC) eyes on a pixel-by-pixel basis. For this retrospective study, we manually corrected the segmentations of posterior pole optical coherence tomography (OCT) scans to determine the thickness of the nerve fiber layer (NFL), ganglion cell layer (GCL), inner plexiform layer (IPL), the ganglion cell complex (GCC), and the total neural retina (TR). For each eye, the total number of pixels with thickness values less than the fifth percentile of the HC distribution was used to create a receiver operating characteristic (ROC) curve for each layer and for layer combinations. Using total abnormal pixel count criteria to discriminate glaucoma from HC eyes, the individual layers with the highest area under the ROC curve (AUC) were the NFL and GCL; IPL performance was significantly lower (P < 0.05). GCC had a significant higher AUC (94.3%) than individual the AUC of the NFL (92.3%) (P = 0.0231) but not higher than AUC of the GCL (93.4%) (P = 0.3487). The highest AUC (95.4%) and sensitivity (85.1%) at 95% specificity was found for the Boolean combination of NFL or GCL. The highest AUC is not significantly higher (P = 0.0882) than the AUC of the GCC but the highest sensitivity is significantly higher than the sensitivity of the GCC. This pattern was similar for discriminating between suspect and HC eyes (P = 0.0356). Using pixel-based methods, the diagnostic accuracy of NFL and GCL exceeded that of IPL and TR. GCC had equivalent performance as NFL and GCL. The specific spatial locations within the posterior pole that exhibit best performance vary depending on which layer is being assessed. Recognizing this dependency highlights the importance of considering multiple layers independently, as they offer complementary information for effective and comprehensive diagnosis.

Ocular effects of synthetic cannabinoids: a case-control study.

To evaluate the ocular effects of "Bonzai", a synthetic cannabinoid (SC), in seropositive and seronegative users. Sixty eyes of 60 consecutive male patients with a history of "Bonzai" use and 30 eyes of 30 age-matched male healthy controls were enrolled in this case-control study. Patients with past "Bonzai" use were grouped as seropositive (n:30) and seronegative (n:30) according to urine toxicology tests. All groups were compared for blood pressures, intraocular pressure, foveal and parafoveal retinal thicknesses, subfoveal and parafoveal choroidal thicknesses, measurements of the peripapillary retinal nerve fibre layer (RNFL), and macular ganglion cell complex (GCC), subfoveal total choroidal, luminal and stromal areas, and choroidal vascularity index (CVI). No differences were noted in blood pressures between the groups (p > 0.05). The mean intraocular pressure was significantly lower in the seropositive group than in the other groups (p < 0.001). Foveal and retinal thicknesses, RNFL, and GCC measurements did not differ between the groups (p > 0.05). Subfoveal and parafoveal choroidal thicknesses and areas were lower in the seropositive group than in the other groups (p < 0.001, for all). CVI increased in both groups with "Bonzai" use compared to the control group (p < 0.001, for all). This study indicates that intraocular pressure may decrease, and choroidal changes may be observed in SC users. Further clinical studies with a larger sample size, especially using purified SC for therapeutic purposes, are needed to confirm the present findings, and further histopathologic studies are required to clarify the changes in the choroid despite SC seronegativity. NCT06235346.

Significant improvement of ganglion cell complex in optical coherence tomography and photopic negative response in electroretinography after transsphenoidal resection of pituitary macroadenoma.

Not required for Clinical Vignette.

Correlation between glycemic control and retinal nerve fiber layer parameters in type 2 diabetics without retinopathy: a case control study

Background Retinal neurodegenerative changes were found to develop in patients with diabetes mellitus (DM) before the onset of microvascular changes of diabetic retinopathy (DR). Such changes usually affect inner retinal layers in the form of retinal nerve fiber layer (RNFL) thinning. Aim To correlate the degree of glycemic control [in the form of hemoglobin A1c (HBA1c) levels] with changes in peripapillary RNFL thickness in patients with type 2 DM without DR using optical coherence tomography (OCT). Patients and methods Participants are divided into three groups each including 28 eyes: group 1: uncontrolled type 2 DM without DR (HBA1c≥7%), group 2: controlled type 2 DM without DR (HBA1c&lt;7%), group 3: healthy age and sex-matched controls. Peripapillary RNFL and macular ganglion cell complex (GCC) thickness were evaluated in all participants using RTVue spectral domain OCT device (Optovue, Fremont, USA). Results Peripapillary RNFL and macular GCC were significantly thinner in the uncontrolled type 2 DM group in comparison to both the controlled type 2 DM group and the healthy control group. No significant difference in OCT parameters between the controlled type 2 DM group and the healthy control group. HBA1c shows a statistically significant negative correlation with average, superior and inferior RNFL thickness as well as average, superior, and inferior GCC thickness. Conclusion Early and adequate glycemic control, indicated by HBA1c less than 7%, is of critical importance in delaying and reducing early neurodegenerative changes in the form of RNFL and GCC thinning in patients with type 2 DM without DR.

Ganglion Cell Complex Thickness and Visual Function in Chronic Leber Hereditary Optic Neuropathy.

To evaluate the correlation between the macular ganglion cell complex (GCC) thickness measured with manually corrected segmentation and visual function in individuals with chronic Leber hereditary optic neuropathy (LHON). Twenty-six chronic LHON subjects (60% treated with idebenone or Q10) from the Swedish LHON registry were enrolled. Best-corrected visual acuity (BCVA), visual field tests, and optical coherence tomography (OCT) were performed. Visual field was evaluated with the Haag-Streit Octopus 900 with the Esterman test and a custom 30° test. Canon OCT-HS100 scans were exported to the Iowa Reference Algorithm. GCC thickness was obtained after the segmentation was corrected manually in nine macular sectors. The GCC thickness was overestimated by 16 to 30 µm in different macular sectors with the automated segmentation compared with the corrected (P < 0.001). GCC thickness in all sectors showed significant correlation with all functional parameters. The strongest correlation was seen for the external temporal sector (BCVA: r = 0.604, P < 0.001; mean defect: r = 0.457, P = 0.001; Esterman score: r = 0.421, P = 0.003). No differences were seen between treated and untreated subjects with regard to GCC and visual field scores (P > 0.05), but BCVA was better among treated subjects (P = 0.017). The corrected GCC thickness showed correlation with visual function in chronic LHON subjects. The frequently occurring segmentation errors in OCT measurements related to chronic LHON can potentially be misleading in monitoring of disease progression and in evaluating the treatment effects. Precise measurements of GCC could serve as a sensitive tool to monitor structural changes in LHON. We therefore emphasize the importance of careful evaluation of the accuracy of OCT segmentation.

Near Add Power of Glaucoma Patients with Early Presbyopia.

Purpose: Glaucoma medication may accelerate the progression of presbyopia. The aim of this study was to compare presbyopia between controls and patients with glaucoma in their 40s. Methods: This was a cross-sectional study of bilateral phakic participants aged between 40 and 49, which included controls (n = 114, mean age 46.1 ± 2.7 y) and patients with primary open-angle glaucoma (n = 105, 46.4 ± 2.7 y) who had been using FP receptor agonists, beta blockers, and carbonic anhydrase inhibitors for at least six months. We compared the near add power between the two groups. Results: The mean near add power and the prevalence of symptomatic presbyopia (near add power ≥ 1.50 D) were 1.16 ± 0.74 D and 42.1% for controls and 1.77 ± 0.71 D (p < 0.01) and 79.0% (p < 0.01) for glaucoma patients, respectively. The odds ratio (OR) and confidence interval for symptomatic presbyopia were associated with age (1.36, 1.21-1.52), ganglion cell complex thickness (0.96, 0.94-0.99), presence of glaucoma (6.19, 3.13-12.23), and number of glaucoma medications (4.26, 2.42-7.43). Among medications, only FP receptor agonists (5.79, 2.68-12.32) produced significant results. Survival analysis showed that glaucoma patients reached the threshold of a near add power of +1.50 D significantly sooner than controls (p < 0.05; log-rank test). Conclusions: Glaucoma patients, especially those using FP receptor agonists, had higher near add power than controls.

Progressive Thickening of Retinal Nerve Fiber and Ganglion Cell Complex Layers Following SDM Laser Vision Protection Therapy in Open-Angle Glaucoma.

This work aims to determine the effect on nerve fiber layer (NFL) and ganglion cell complex (GCC) thickness trends in eyes with open-angle glaucoma (OAG) treated with Vision Protection Therapy™ (VPT). A retrospective analysis of spectral-domain optical coherence tomography (OCT) measured NFL and GCC thickness trends was performed, excluding eyes with poor-quality scans and principal diagnoses other than OAG. This study compares eyes with OAG managed conventionally with IOP control alone (controls) to eyes managed with the addition of VPT (VPT eyes). The direction (+ or -) and magnitude (microns/year) of the OCT trends were the study endpoints. Seventy-eight control eyes of 40 patients and 61 VPT-treated eyes of 39 patients were included in the study. Positive NFL trends were noted in 5% of control eyes vs. 71% of VPT eyes (p < 0.0001). Positive GCC trends were noted in 8% of control eyes vs. 43% of VPT eyes (p < 0.0001). Mean NFL trends (µm/year) were - 0.692 for controls vs. 0.347 for VPT (p < 0.0001). Mean GCC trends (µm/year) were - 0.554 for controls vs. - 0.148 for VPT (p = 0.0175). The addition of VPT to the conventional management of OAG resulted in highly significant improvements in NFL and GCC trends, indicating a reversal of key indicators of glaucoma severity and progression.

Evaluation of insomnia effect on ganglion cell complex, middle retina, and choroid

Evaluation of insomnia effect on ganglion cell complex, middle retina, and choroid

Comparative of OCT and OCTA parameters in patients with early chronic angle-closure glaucoma and early pituitary adenoma

Optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) have the potential application in evaluating pathological structural change of the optic nerve. We aimed to evaluate the value of the OCT and OCTA parameters of the optic disk and macular in differentiating early chronic primary angle-closure glaucoma (CPACG) and early pituitary adenoma (PA) in case of mild visual field defects (the mean defect (MD) > 6 dB). The results showed that regarding OCTA parameters, CPACG patients had lower retinal blood flow density of most layers of the optic disk and macular than PA patients. Regarding OCT parameters, CPACG patients had thinner circumpapillary retinal nerve fiber layer (CP-RNFL) in all quadrants and average CP-RNFL, ganglion cell layer (GCL) and macular ganglion cell complex (GCC) in each quadrant of macular inner and outer rings, and inner plexus layer (IPL) of macular inner ring, superior-outer ring and temporal-outer ring than PA patients. The Z test indicated that OCTA parameters and OCT parameters had similar value in the diagnosis of disease. In conclusion, in the case of similar visual field damage, early CPACG patients have smaller blood flow density and thinner optic disk and macular than early PA. OCTA has similar performance to OCT in diagnosing CPACG and PA.

Evaluating the impact of polycythemia vera on retinal and optic nerve head microvascularity: An OCTA study.

This study aims to assess the impact of polycythemia vera (PV) on retinal and optic nerve head (ONH) vessel density (VD) parameters, macular ganglion cell complex (mGCC) thickness, and retinal nerve fiber layer (RNFL) thickness compared to healthy controls. Forty eyes of 20 patients with PV and 40 eyes of 20 age-gender-matched healthy controls underwent comprehensive ophthalmologic assessments and optic coherence tomography angiography (OCTA). RNFL and macular GCC measurements were obtained simultaneously with vascular parameters by AngioVue OCTA using the single-scan protocol. Peripapillary VD was examined across eight sectors, whereas parameters including RNFL, GCC, and macular VD were analyzed in four quadrants. Patients with PV exhibited significant reductions in the average RNFL thickness (P = 0.014) and RNFL thickness in superior (P < 0.001) and inferior (P = 0.003) quadrants compared to controls. Additionally, mGCC thickness in all quadrants significantly reduced in the PV group (P < 0.001). ONH VD parameters, including whole-image VD (P < 0.001) and peripapillary VD (P < 0.001), were significantly reduced in patients with PV. Similarly, macular VD parameters were significantly lower in the PV group (P < 0.001). This study highlights substantial vascular and structural alterations in the retina and ONH of patients with PV compared to healthy controls. These changes likely stem from microvascular dysfunction associated with PV. These findings suggest further research to understand the underlying mechanisms and develop targeted therapeutic strategies for managing ocular complications in patients with PV.

Using Multi-Layer Perceptron Driven Diagnosis to Compare Biomarkers for Primary Open Angle Glaucoma.

To use neural network machine learning (ML) models to identify the most relevant ocular biomarkers for the diagnosis of primary open-angle glaucoma (POAG). Neural network models, also known as multi-layer perceptrons (MLPs), were trained on a prospectively collected observational dataset comprised of 93 glaucoma patients confirmed by a glaucoma specialist and 113 control subjects. The base model used only intraocular pressure, blood pressure, heart rate, and visual field (VF) parameters to diagnose glaucoma. The following models were given the base parameters in addition to one of the following biomarkers: structural features (optic nerve parameters, retinal nerve fiber layer [RNFL], ganglion cell complex [GCC] and macular thickness), choroidal thickness, and RNFL and GCC thickness only, by optical coherence tomography (OCT); and vascular features by OCT angiography (OCTA). MLPs of three different structures were evaluated with tenfold cross validation. The testing area under the receiver operating characteristic curve (AUC) of the models were compared with independent samples t-tests. The vascular and structural models both had significantly higher accuracies than the base model, with the hemodynamic AUC (0.819) insignificantly outperforming the structural set AUC (0.816). The GCC + RNFL model and the model containing all structural and vascular features were also significantly more accurate than the base model. Neural network models indicate that OCTA optic nerve head vascular biomarkers are equally useful for ML diagnosis of POAG when compared to OCT structural biomarker features alone.

Study of corneal and retinal thicknesses at five years after FS-LASIK and SMILE for myopia

BackgroundThis study aimed to observe corneal and retinal thicknesses at 5 years after femtosecond laser-assisted in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) for myopia, investigate the effect of epithelial remodeling on refractive status and visual quality, and compare retinal thicknesses among fundus tessellation grades.MethodsPatients who received FS-LASIK or SMILE 5 years before were enrolled in this cross-sectional study. After 1:1 propensity score matching, each surgical group obtained 177 patients (177 eyes). Examinations including visual acuity, refraction, corneal and retinal thicknesses, corneal higher-order aberrations (HOAs), and fundus photography were performed in this visit at 5 years after surgery. The Quality of Vision (QoV) questionnaire was used to assess visual symptoms and overall satisfaction. Corneal and retinal thicknesses between groups were compared, contributing factors were analyzed, and correlations with postoperative refractive status, HOAs, QoV scores and overall satisfaction were evaluated.ResultsThe discrepancy of epithelial thickness between central and pericentral zones in FS-LASIK group was larger than that in SMILE group, which was negatively correlated with postoperative spherical equivalent (SE), positively correlated with spherical aberration (all P < 0.05), but not correlated with QoV scores and overall satisfaction (all P > 0.05) in both surgical groups. There was no statistical difference in stromal thickness and total corneal thickness (all P > 0.05). Most annuluses of epithelial and stromal thicknesse were linearly related to preoperative SE (all P < 0.05). The macular thickness, ganglion cell complex thickness, and retinal nerve fiber layer thickness exhibited comparable values between two surgical groups and four fundus tessellation grades, with no significant association observed with postoperative SE (all P > 0.05).ConclusionThe tendency that epithelial thickness in central zone was thicker than peripheral zone was more obvious at 5 years after FS-LASIK compared to SMILE. This uneven distribution of epithelial thickness might play a role in myopic regression and the changes in HOAs, especially in patients with high myopia, but it had little effect on patients’ subjective visual quality and satisfaction. Retinal thicknesses were not affected by these two surgical methods, and they did not appear to be the clinical indicators for myopic regression or fundus tessellation progression.

Delayed Surgical Reversal of Optic Nerve Compression Leads to Exponential Degeneration of Optic Nerve Fibers and Selective Sparing of the Small Fibers.

To evaluate the effectiveness of surgical reversal of experimental optic nerve compression in treating persistent compressive optic neuropathy and to explore the relationship between surgical outcomes and the timing of the procedure. Surgical reversal procedures (decompression surgery) were conducted at five time intervals: 1, 3, and 7 days and 2 and 3 weeks following optic nerve compression in a rabbit model. The groups were labeled as DC-1d, DC-3d, DC-7d, DC-2w, and DC-3w, respectively. The study investigated changes in ganglion cell complex (GCC) thickness using spectral-domain optical coherence tomography and the percentage of surviving retinal ganglion cells (RGCs) through immunofluorescence staining and optic nerve axons stained with p-phenylenediamine at 4 weeks after decompression. Additionally, the area distribution of surviving axons was analyzed. The decline in GCC thickness was halted following decompression. The remaining thickness of the GCC in group DC-1d was found to be statistically significantly higher at 2, 3, and 4 weeks postonset compared to the no-decompression group. Similarly, GCC thickness in group DC-3d was significantly higher at 3 and 4 weeks postonset. The percentage of surviving RGCs and axons at 4 weeks postonset exhibited an exponential correlation with the onset time of decompression, with R2 values of 0.72 and 0.78, respectively. The surviving axon area declined following delayed decompression. Persistent substantial compression on the optic nerve leads to exponential degeneration of the optic nerve, initially affecting larger optic nerve fibers. Early intervention aimed at relieving the compression on the optic nerve may offer potential benefits in mitigating the degenerative effects and conserving visual function.