Retinal Nerve Fiber Layer Thickness Research Articles

Retinal Vascular Changes in Vitiligo: A Novel Approach Using OCTA

ABSTRACT Purpose This study aimed to the detect of structural and functional changes in the retina and choroid in patients with vitiligo using optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). Materials and Methods Thirty patients with vitiligo and 30 healthy participants were enrolled in the study. Central macular thickness (CMT), retina nerve fiber layer (RNFL) thickness, choroidal thickness (CT), foveal avascular zone (FAZ) area, and superficial and deep vascular density (VD) ratios were compared between the groups. Results The mean age was 43.32 ± 12.13 and 45.90 ± 7.50 years, respectively (p = 0.435). CMT, RNFL thicknesses (except temporal quadrant), CT, superficial and deep VD, and FAZ area were similar between the two groups (p > 0.05 for all). Temporal RNFL thicknesses were lower in vitiligo patients than in control groups (p = 0.005). There was a moderate negative correlation between the duration of vitiligo disease and the mean RNFL thickness, inferior RNFL thickness, superficial total, superior, superior inner, outer, and superior outer VD values. No correlation was found between the VASI (Vitiligo area scoring index) score in vitiligo patients and OCT and OCTA values. Conclusion Although it is known that vitiligo causes melanocyte loss in ocular tissues, there was no significant effect of vitiligo on superficial and deep retinal VD. Further comprehensive studies with a larger and more diverse population of vitiligo patients are needed to explore this further.

Use of a Novel Virtual Reality-Based Pupillography Device for Glaucoma Management: Cross-Sectional Cohort Pilot Study.

Current standard methods in monitoring glaucoma progression, like optical coherence tomography (OCT) and standard automated perimetry (SAP), have limitations in certain cases. Automated relative afferent pupillary defect (RAPD) and pupillary light reflex (PLR) testing may offer more objective alternatives. This pilot study aimed to evaluate whether RAPD could sufficiently distinguish between the two eyes in asymmetrical glaucoma, and thus could lay the foundation for using the PLR of a single eye to monitor progression longitudinally. Twenty-one patients underwent quantitative PLR measurements using a virtual reality headset. RAPD was calculated by subtracting the amplitude of PLRs between eyes. Both RAPD and relative SAP (measured using the mean defect or MD) results were correlated to the thickness of the peripapillary retinal nerve fiber layer (RNFL), as measured by OCT. Data from 18 patients was analyzed after exclusions. RAPD significantly correlated with differences between the two eyes as measured by RNFL thickness (Pearson r = 0.79, p = 0.05). MD differences correlated slightly better with RNFL differences (Pearson r = 0.87, p < 0.05). RAPD and MD combined yielded an improved prediction of RNFL differences by 5% compared to using MD only. RAPD measurements reliably detected asymmetries in optic nerve damage in glaucoma patients. SAP measurements correlated better with OCT results than RAPD results. However, SAP and RAPD combined led to an improved prediction of RNFL thickness. This could possibly allow us to use PLR only over longer periods of time to monitor glaucomatous optic nerve damage in a single eye in the future.

Five-Year Outcomes of Deep Sclerectomy in Pseudoexfoliation Glaucoma Compared to Primary Open-Angle Glaucoma.

Objectives: This study aimed to investigate the five-year outcomes of deep sclerectomy (DS) in patients with pseudoexfoliation glaucoma (PEXG) and primary open-angle glaucoma (POAG). Methods: This retrospective, observational, unicentric study analyzed POAG and PEXG patients. Intraocular pressure (IOP), the number of IOP-lowering medications, peripapillary retinal nerve fiber layer (RNFL) thickness, the number of postoperative interventions, surgical success rates, and secondary surgery rates were evaluated at baseline and during follow-up appointments. Results: A total of 109 POAG and 153 PEXG eyes were included. Over the 5-year follow-up, IOP decreased in both groups (p = 0.17), from 22.8 ± 0.7 to 13.3 ± 0.6 mmHg (p < 0.001; POAG) and from 24.3 ± 0.8 to 16.6 ± 1.2 mmHg (p < 0.001; PEXG). The number of IOP-lowering medications decreased comparably (p = 0.99), from 3.1 ± 0.1 to 1.7 ± 0.3 (p = 0.001; POAG) and from 3.4 ± 0.1 to 1.7 ± 0.2 (p < 0.001; PEXG). Peripapillary RNFL thickness decreased in both groups (p = 0.31), from 60.6 ± 1.9 to 54.2 ± 2.4 µm (p < 0.001; POAG) and from 63.1 ± 1.7 to 58.0 ± 2.3 µm (p < 0.001; PEXG). The 5-year complete success rates were 33% and 12% for the POAG and PEXG groups, respectively (p = 0.01). The qualified success rates were 63% and 40% (p = 0.03). Secondary glaucoma surgery was required in 8% of POAG eyes and 21% of PEXG eyes (p = 0.04). Conclusions: DS resulted in comparable results for IOP, medications, and RNFL development in the PEXG and POAG groups but in less favorable outcomes concerning surgical success and further necessary repeated glaucoma surgery in patients with PEXG over the 5-year follow-up period.

Macular retinal nerve fiber layer thickness in retinitis pigmentosa patients with and without optic disc drusen

IntroductionRetinitis pigmentosa (RP) is a group of inherited retinal dystrophies characterized by progressive photoreceptor degeneration. In a recent study, we reported co-existing optic disc drusen (ODD) at 30%, a prevalence 15 times higher than in the general population. The aims of this study were to a) assess if macular retinal nerve fiber layer thickness (RNFLt) was increased in our cohort of RP patients and b) compare RNFLt between RP patients with and without ODD.MethodsIn this post-hoc analysis, optical coherence tomography (OCT) scans of patients with RP and healthy controls were manually delineated, and macular RNFLt measurements were obtained. The analyses were conducted both a) for RP patients without ODD compared to controls and b) for RP patients with and without ODD.ResultsOCT scans of 32 patients with RP and 13 healthy controls were included. Macular RNFLt was significantly increased in RP patients compared to healthy controls and in RP patients with ODD compared to RP patients without ODD.DiscussionFurther studies will explore whether increased RNFLt leads to ODD development through dystrophic calcification or, conversely, if ODD in combination with RP-associated retinal ganglion cell damage causes the increased RNFLt through retrograde axoplasmic stasis.

Optical Microangiography and Progressive Retinal Nerve Fiber Layer Loss in Primary Angle-closure Glaucoma

Precis Younger patient age (coefficient: 0.10, P=0.04) and greater peak IOP during follow-up (coefficient: -0.14, P=0.03), but not baseline optical microangiography parameters, were significantly associated with a faster rate of RNFL loss in mild-moderate PACG. Purpose: To evaluate the association between optical microangiography (OMAG) measurements and progressive retinal nerve fiber layer (RNFL) loss in primary angle-closure glaucoma (PACG). Methods: In a prospective study, 45 eyes of 30 PACG patients (86 hemifields) with mild to moderate functional damage were longitudinally studied for at least 2 years and with a minimum of 3 optical coherence tomography (OCT) examinations. OMAG imaging was performed at the baseline visit. Effect of clinical parameters (age, gender, presence of systemic diseases, central corneal thickness, mean, peak and fluctuation of intraocular pressure during follow-up), baseline hemifield mean deviation (MD) and baseline OMAG (quadrant peripapillary and macular perfusion density [PD]) on the rate of RNFL change was evaluated using linear mixed models. Results: Average (±SD) hemifield MD, RNFL thickness, peripapillary PD and macular PD of the analyzed quadrants at baseline were -6.0±3.4 dB, 89±21 µm, 40.1±3.5% and 29.6±10.3%, respectively. Rate of quadrant RNFL change was -2.5±1.7 µm/year. Multivariate mixed models showed that younger patient age (coefficient: 0.10, P=0.04) and higher peak IOP during follow-up (coefficient: -0.14, P=0.03) were significantly associated with a faster rate of RNFL loss. Conclusions: Younger patient age and greater peak IOP during follow-up were significantly associated with a faster rate of RNFL loss in PACG patients with mild to moderate severity of functional damage. None of the OMAG parameters at baseline were associated with RNFL thinning suggesting a limited role of OCTA imaging in predicting structural progression in mild-moderate PACG.

The Effects of Antioxidant Cocktail on Ophthalmological Changes Induced by a 60-Day Head-Down Bed Rest in a Randomized Trial

Neuro-ophthalmological changes have been reported after prolonged exposure to microgravity; however, the pathophysiology remains unclear. Furthermore, several countermeasures have been suggested to counteract the side effects of microgravity. The objectives of the present study were twofold: (1) to assess the neuro-ophthalmological impact of 60 days of head-down bed rest (HDBR) and (2) to determine the potential effects of an antioxidant cocktail. In this case, 20 healthy male subjects completed a 60-day HDBR and were randomly allocated into two groups: a control condition without an antioxidant cocktail (CON) and a condition with an antioxidant cocktail (NUT). The retinal nerve fibre layer thickness (RNFLT) and central retinal thickness (CRT) were assessed with spectral domain optical coherence tomography. The optic nerve sheath diameter (ONSD) was measured by ocular ultrasonography and used to assess indirect changes in the intracranial pressure (ICP). The intraocular pressure (IOP) was assessed by Goldmann applanation tonometry. The CRT tended to be reduced after HDBR. The ONSD was increased at the end and after HDBR. The IOP tended to decrease after HDBR. Finally, the antioxidant cocktail had minor impacts on the ophthalmological changes induced by HDBR. It is worth noting that two participants presented peripapillary edema.

Long-Term Effect of Intravitreal Brolucizumab Injections on Peripapillary Retinal Nerve Fiber Layer Thickness in Patients with Refractory Polypoidal Choroidal Vasculopathy

Long-Term Effect of Intravitreal Brolucizumab Injections on Peripapillary Retinal Nerve Fiber Layer Thickness in Patients with Refractory Polypoidal Choroidal Vasculopathy

Association of peripapillary retinal nerve fiber layer atrophy with cognitive impairment in patients with neuromyelitis optica spectrum disorder.

We aimed to explore the association between peripapillary retinal nerve fiber layer thickness (pRNFL), macular ganglion cell-inner plexiform layer (mGCIPL), and cognitive impairment (CI) in patients with neuromyelitis optica spectrum disorder (NMOSD). In this cross-sectional study, 38 (28 aquaporin-4 (AQP4) IgG-seropositive) NMOSD patients and 20 healthy controls (HC) underwent cognitive assessment using Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) battery. Spectral-domain optical coherence tomography (OCT) was performed for both eyes of all NMOSD patients. First, we examined the association of pRNFL and mGCIPL with cognitive function in all patients, regardless of the history of previous optic neuritis (ON). We then included only eyes without a prior history of ON, incorporating non-ON eyes in patients with unilateral ON and the average of OCT measures for both non-ON eyes in patients without a history of ON. Sixteen (42.1%) NMOSD patients exhibited global CI. There was a significant decrease in pRNFL (Δ: 24.33μm, p = 0.002) and mGCIPL (Δ: 9.20μm, p = 0.009) in NMOSD patients with CI compared to those without. The atrophy of pRNFL showed an inverse association with CI before (OR = 1.059, 95% CI: 1.015, 1.105) and after adjustment for age, sex, and disease duration (OR = 1.072, 95%CI: 1.009, 1.139). An inverse significant association was observed between mGCIPL atrophy and CI before adjustment (OR = 1.102, 95% CI: 1.017, 1.194), but not after adjustment (OR = 1.106, 95%CI: 0.999, 1.224). After narrowing our analysis to non-ON eyes, the same results for pRNFL and CI were observed (unadjusted: OR = 1.054, 95% CI: 1.004, 1.106; adjusted: OR = 1.081, 95%CI: 1.000, 1.168). There was no significant association found between mGCIPL thickness and CI in both unadjusted and adjusted models. In sensitivity analyses, we observed no significant association between pRNFL and mGCIPL with CI in AQP-IgG-seropositive NMOSD patients. This study, for the first time, provide a preliminary evidence for a possible relation between pRNFL atrophy and occurrence of cognitive impairment in NMOSD patients. Further studies are required to explore the possible association of OCT parameters with cognition function in NMOSD patients.

Primary Visual Pathway Changes in Individuals With Chronic Mild Traumatic Brain Injury

Individuals with mild traumatic brain injury (TBI) often report vision problems despite having normal visual acuity and fundus examinations. Diagnostics are needed for these patients. To determine if a battery of assessments or machine-learning approaches can aid in diagnosing visual dysfunction in patients with mild TBI. This prospective, observational, case-control study was conducted between May 2018 and November 2021. The study setting was at a level 1 trauma research hospital. Participant eligibility included adult males and females with recorded best-corrected visual acuity and normal fundus examination. Individuals in the case group had a history of mild TBI; controls had no history of TBI. Exclusion criteria included a history of ocular, neurological, or psychiatric disease, moderate-severe TBI, recent TBI, metal implants, age younger than 18 years, and pregnancy. Cases and controls were sex- and age-matched. Data analysis was performed from July 2023 to March 2024. History of mild TBI in the case group. The single-session visit included the Neurobehavioral Symptom Inventory and measurements of oculomotor function, optical coherence tomography, contrast sensitivity, visual evoked potentials, visual field testing, and magnetic resonance imaging. A total of 28 participants (mean [SD] age, 35.0 [12.8] years; 15 male [53.6%]) with mild TBI and 28 controls (mean [SD] age, 35.8 [8.5] years; 19 female [67.9%]) were analyzed. Participants with mild TBI showed reduced prism convergence test breakpoint (-8.38; 95% CI, -14.14 to -2.62; P = .008) and recovery point (-8.44; 95% CI, -13.82 to -3.06; P = .004). Participants with mild TBI also had decreased contrast sensitivity (-0.07; 95% CI, -0.13 to -0.01; P = .04) and increased visual evoked potential binocular summation index (0.32; 95% CI, 0.02-0.63; P = .02). A subset of participants exhibited reduced peripapillary retinal nerve fiber layer thickness, increased optic nerve/sheath size, and brain cortical volumes. Machine learning identified subtle differences across the primary visual pathway, including the optic radiations and occipital lobe regions, independent of visual symptoms. Results of this case-control study suggest that the visual system was affected in individuals with mild TBI, even in those who did not self-report vision problems. These findings support the utility of a battery of assessments or machine-learning approaches to accurately diagnose this population.

Analysis of Optic Disc Morphology and the Peripapillary Retinal and Choroidal Thickness by the Swept Source Optical Coherence Tomography in Patients with Moyamoya Disease

Introduction: Moyamoya Disease (MMD) is a chronic cerebrovascular occlusive disorder. Ocular involvement in patients with MMD has increasingly been recognized and reported in recent years. This study aimed to investigate the changes of optic disc morphology and the peripapillary retinal and choroidal thickness in patients with MMD. Methods: This cross-sectional study included 56 patients diagnosed with idiopathic MMD and 56 healthy controls matched by age and gender. All participants underwent swept-source optical coherence tomography to capture the optic disc morphology as well as the peripapillary retinal and choroidal thickness. Optic disc parameters, including cup area, rim area, cup volume, rim volume, C/D area ratio (CDR), linear CDR, and vertical CDR were measured and compared between the two groups. Additionally, the thickness of the peripapillary whole retina, retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and choroid were evaluated and analyzed across 12 clock-hour segments around the peripapillary region. Results: The rim area in MMD patients was significant less than controls while the CDR in MMD patients was significantly larger than that in the control group. There was no statistically significant difference between the two groups regarding disc area, cup area, cup volume, rim volume, vertical and horizontal diameter of disc. The retinal thickness at the 7 o'clock position was significantly thinner in the MMD group compared to the control group and the temporal RNFL thickness, particularly at the 7 o'clock and 9 o'clock positions, was significantly reduced in the MMD group (p&lt;0.05). The GCL layer at the 7 o'clock position was thinner in the MMD group than in the control group (p&lt;0.05). The MMD group showed a notably reduced average choroidal thickness, particularly in the inferior-temporal region (p&lt;0.05). There was a correlation between peripapillary choroidal and GCL layer thickness in the MMD group, but no significant correlations were found with rim area, CDR, or RNFL. Conclusions: In patients with MMD, there is an increase in the CDR accompanied by a decrease in the rim area. Additionally, there is thinning of the temporal RNFL, GCL, and choroidal thickness, notably in the inferotemporal quadrant of the optic disc.

Optical coherence tomography as an adjunct tool to assess response to treatment in cerebral venous thrombosis: A prospective longitudinal study

IntroductionPapilledema, due to raised intracranial pressure (ICP) is commonly seen in cerebral venous thrombosis (CVT) and can have serious complications. This study reports the quantitative assessment of papilledema through the measurement of the Peripapillary choroidal thickness (ChT) and Peripapillary retinal nerve fiber layer thickness (RNFLT) using optical coherence tomography (OCT). MethodsWe conducted a prospective longitudinal study of 30 subjects with CVT. Age and gender-matched healthy individuals were included as controls. In addition to history, RNFLT and ChT measurements were obtained at presentation, discharge, and follow-up two months after discharge. ResultsThe mean age of the patients was 32.8 ± 9.9 years. Papilledema was seen in 14 (46.66 %) patients. The peripapillary RNFLT and ChT were significantly greater in patients with CVT [RNFLT 121.5 μm (105,169) in the right eye (RE), 120 μm (103,148) in the left eye (LE); ChT 159 μm (143,171) in the RE, 155.5 μm (140,166) in the LE] as compared to controls [RNFLT 106.5 μm (102,111) in RE, 103.5 μm (98,107) in LE; ChT 130 μm (119,134) in RE, 124 μm (119,136) in LE]. There was a significant decrease in the peripapillary RNFLT and ChT in patients with papilledema at follow-up after two months in all segments in both eyes. ConclusionIn patients with CVT, RNFLT, and ChT reduced significantly with treatment. OCT is potentially useful to objectively assess response to treatment in patients with CVT.

An eye’s look unmasks the mystery: correlation between serum amyloid beta peptide, hippocampal volume and retinal thickness in Alzheimer`s disease

BackgroundAlzheimer’s disease (AD) is the commonest worldwide neurodegenerative disorder. Nevertheless, it usually face difficulties to guarantee a secured initial diagnosis. For this reason, neurologists are in dire need for developing potential biomarkers that could be relied upon confidentially in early diagnosis of AD. Hopefully, this will open the gate for novel modifying therapy to fight with all their might. In this current study, we aimed to correlate plasma levels of tau and Aβ with the changes that occur in hippocampal volume and thickness of retinal fiber layers in patients who clinically diagnosed with AD spectrum. A cross-sectional study enrolled 60 AD patients who fulfilled inclusion and exclusion criteria were subjected to cognitive, radiologic, laboratory and optical coherence tomography (OCT) assessments.ResultsTau, Aβ1–40, and Aβ1–40/Aβ1–42 ratio are significant discriminators of AD at cutoff values of >23.45, > 84.4, and > 1.95, respectively. MRI hippocampal volume in both right and left sides are also good discriminators of AD at cutoff values of ≤ 2.997, and ≤ 2.994, respectively. A significant correlations were reported between tau with Aβ1–40, Aβ1–42, MMSE and MRI right and left hippocampal volumes. On comparing moderate versus mild AD, there was a high significant levels of tau, Aβ1–42, Aβ1–40/Aβ1–42 ratio.ConclusionsWe clarify that several biomarkers could be potentially used for confirming the diagnosis of AD. Assessment of plasma amyloid level, detection of hippocampal atrophy and retinal nerve fiber layer thickness changes are promising tools for early diagnosis of AD.

Diagnostic model of microvasculature and neurologic alterations in the retina and optic disc for lupus nephritis

BackgroundMachine learning (ML) analysis of retinal nerve fiber layer (RNFL) thickness and vessel density (VD) alterations in the macular region and optic disc may provide a new diagnostic method for lupus nephritis (LN). This study aimed to assess these alterations in LN patients using optical coherence tomography angiography (OCTA). MethodsA retrospective analysis was conducted on 81 systemic lupus erythematosus (SLE) patients without retinopathy, divided into two groups: LN (41 patients) and non-LN (39 patients). OCTA imaging was performed on all participants. Independent risk factors were identified through univariate and multivariate analyses, followed by the development of a random forest (RF) diagnostic model. ResultsA total of 37 RNFL and VD variables from the macular region and 23 from the optic disc were analyzed. Through elastic net regression, 16 significant factors were identified. Further multivariate logistic regression selected 8 critical factors, which were used to construct the RF model. The RF model achieved an area under the curve (AUC) of 0.950 (95 % CI: 0.882 to 1.000), accuracy of 0.903 (95 % CI: 0.743 to 0.980), sensitivity of 0.867, specificity of 0.938, a positive predictive value (PPV) of 0.929, and a negative predictive value (NPV) of 0.882. ConclusionThis study highlights the potential of ML-based OCTA data in diagnosing LN. Key diagnostic factors included perimeter (PERIM), superficial capillary plexus vessel density (SVD) - parafoveal (para)-temporal (T), SVD-perifoveal (peri)-inferior (I), RNFL-Fovea, RNFL-Peri, RNFL-Peri-T, capillary-whole-image, and peripapillary RNFL (PRNFL)- inferonasal (IN).

Intraocular pressure and optical coherence tomography concerning visual field outcomes in "green" patients: An observational study.

This study investigates the relationship between intraocular pressure (IOP), optical coherence tomography (OCT) parameters, and visual field (VF) outcomes in 'Green' patients-those with normal OCT findings but potential VF abnormalities. Understanding this relationship is crucial for improving early detection and management strategies for glaucoma, especially in patients who show functional loss despite normal structural findings on OCT. A cross-sectional study was conducted at Taipei City Hospital, Renai Branch, Taiwan, from July 1, 2015, to July 1, 2023. Participants were referred for suspected glaucoma and included based on normal OCT parameters ('green' coding) and completed VF tests. Patients with any ocular disease that could confound results were excluded. Logistic regression models were used to assess relationships between IOP, OCT parameters (rim area, disc area, retinal nerve fiber layer thickness, cup-to-disc ratios, and cup volume), and VF outcomes. Age, sex, and IOP status (normal or ocular hypertension) were also included in the analysis. All data were analyzed using Statistical Package for the Social Sciences version 23.0. Larger disc area was a significant predictor of VF abnormalities, with an adjusted OR of 3.72 (95% confidence interval [CI], 1.14-12.15). Neither normal IOP nor ocular hypertension significantly predicted VF loss (adjusted OR = 0.89; 95% CI, 0.27-2.96). Female sex was associated with a higher likelihood of VF abnormalities (adjusted OR = 5.68; 95% CI, 1.03-31.25). Other OCT parameters, including retinal nerve fiber layer thickness and cup-to-disc ratios, were not significantly associated with VF outcomes. Disc area plays a critical role in predicting VF abnormalities in "green" patients, suggesting the importance of integrating disc size into screening and monitoring protocols. These findings challenge the reliance on IOP alone for predicting VF loss and support the need for more comprehensive assessments. Future research should explore longitudinal studies to further assess the predictive value of disc area and investigate additional factors, such as vascular and biomechanical influences, that may contribute to VF deterioration in this population.

Earliest location of glaucomatous retinal nerve fibre layer damage is determined by intact baseline RNFL thickness profile

Background/aimsTo identify whether an intact retinal nerve fibre layer (RNFL) thickness profile could determine the location of the earliest RNFL defect in glaucoma.MethodsRetrospective longitudinal cohort study of patients with initial...

Clinical efficacy of optical coherence tomography parameters to predict the visual field outcome following pituitary adenoma surgery.

To investigate the factors affecting visual field recovery in patients with pituitary adenoma following surgical removal, both eyes of 35 patients with pituitary adenoma who had been followed up for > six months post-surgery were retrospectively analyzed. Pre- and post-operative visual acuity, visual field test, retinal nerve fiber layer (RNFL), and ganglion cell inner plexiform layer (GCIPL) thickness were investigated. The average age of the 35 patients was 58.3 ± 11.5 years. Preoperatively, 30 eyes (mean average RNFL thickness, 99.73 ± 5.89 μm) and 40 eyes (mean average RNFL thickness, 77.55 ± 8.35 μm) were included in the thick (≥ 90 μm) and thin RNFL group (< 90 μm), respectively. In the thick RNFL group, pre- and post-operative mean deviation (MD) and pattern standard deviation (PSD) were favorable (all p < 0.001), and the proportion of eyes of postoperative MD change which were stable or improved was greater than in the thin RNFL group (p = 0.042). Preoperative MD, RNFL (except nasal quadrant) and GCIPL thickness were positively correlated to postoperative MD values (all, p < 0.05). Preoperative MD and temporal RNFL thickness were significantly correlated with postoperative MD change rate (p = 0.03 and 0.04, respectively). Preoperative GC IPL thickness and postoperative MD change rate were not significantly correlated (p = 0.61). Using univariate regression analysis, preoperative best corrected visual acuity (Odds ratio [OR], 0.050; p < 0.001), tumor volume (OR, 1.110, p = 0.002), higher preoperative MD values (OR, 0.858; p < 0.001), lower preoperative PSD values (OR, 1.169, p = 0.002), thick RNFL (OR, 0.215; p = 0.003) and thick GCIPL (OR, 0.305, p = 0.018) were significantly associated with a good visual field outcome following surgery. According to multivariate analysis, any other parameters were not significant. In patients with thick RNFL, postoperative MD values were better than in the thin RNFL group. Eyes with preoperative higher MD and thick temporal RNFL showed more improvement in their visual fields postoperative. Preoperative thick RNFL could be a potential predictor of visual field recovery following TSA-TR, while macular GCIPL thickness does not appear to be a reliable predictor.

Evaluation of the macula, retinal nerve fiber layer and choroid thickness in premature ovarian failure using spectral-domain optical coherence tomography.

The aim of our study is to describe the basal findings at the first diagnosis of the disease in patients with premature ovarian failure (POF) and to draw attention to the early changes in the macula, optic nerve head and choroid. In a prospective case-control study, 90 patients with POF and 90 control patients were evaluated. All participants underwent the same ophthalmic examination, including visual acuity, intraocular preasure measurement, anterior and posterior segment evaluation, macular and coroidal thickening, and retinal nerve fiber layer (RNFL) measurements with the same device (Spectral Domain OCT, software version 5.6.3.0, Heidelberg, Germany). The median age was 30.00 (28.00-31.00) in the control group and 29.00 (27.00-31.00) in the POF group (p = 0.249). The median thickness of the temporal outer macular region was statistically significantly thinner in the POF group (295.00 (289.00-303.25)) compared to the control group (306.00 (290.75-328.00)) (p < 0.001). There was a statistically significant decrease in all choroidal regions (p < 0.001), including the central, nasal 500, nasal 1500, temporal 500, and temporal 1500 regions in the POF group according to the control group. An increase in intraocular pressure in the postmenopausal period has been reported, suggesting a link between the postmenopausal decline in sex hormones and glaucoma. Our study is the first to monitor changes in choroidal, retinal thickness and RNFL in POF images showing early menopausal symptoms.

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.

TMIC-15. GUT MICROBIOTA CONTROLS NEUROFIBROMATOSIS-1 (NF1) OPTIC GLIOMA GROWTH THROUGH IMMUNE CIRCUIT MODULATION

Abstract Changes in the gut microbiome can have profound effects on the nervous system through modulation of T cell and microglia function. Since our prior studies demonstrated that T cells and microglia positively regulate low-grade glioma growth through the establishment of T cell-microglia immune circuit, we sought to explore the impact of changes in the gut microbiota on tumor biology. For these studies, genetically engineered Neurofibromatosis type 1 (NF1) optic glioma (Nf1-OPG) mice were raised in a germ-free environment or treated with antibiotics to deplete gut bacteria. First, we demonstrated that Nf1-OPG mice raised in a germ-free (gnotobiotic) environment or treated with specific antibiotics lacked optic gliomas and had improved OPG-induced retinal pathology (increased retinal nerve fiber layer thickness). Second, germ-free and antibiotic-treated Nf1-OPG mice gavaged with fecal microbiota from Nf1-OPG mice raised in a standard barrier facility restored optic glioma growth. Third, we showed that both germ-free and antibiotic-treated Nf1-OPG mice exhibited reduced intra-tumoral CD8+ T cell content resulting from decreased microglia chemokine production. Fourth, we discovered a gut-brain paracrine axis whose interruption reduced optic glioma growth and attenuated retinal nerve fiber layer thinning. Collectively, these findings establish a mechanistic relationship between the gut microbiota and brain tumor growth relevant to potential therapeutic interventions for pediatric low-grade gliomas.

Angioarchitectural alterations in the retina and choroid in frontotemporal dementia.

Frontotemporal dementia (FTD) is a progressive neurodegenerative disorder that affects the frontal and temporal lobes of the brain, leading to cognitive decline and personality changes. The objective of this cross-sectional study was to characterize angioarchitectural changes in the retina and choroid of individuals with FTD compared to cognitively normal controls using optical coherence tomography (OCT) and OCT angiography (OCTA). Cross-sectional comparison of patients with FTD and controls with normal cognition. All participants underwent Mini-Mental State Examination (MMSE) at the time of imaging. Outcome measures included OCT parameters: retinal nerve fiber layer (RNFL) thickness, ganglion cell layer-inner plexiform layer (GC-IPL) thickness, central subfield thickness (CST), subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI); and OCTA superficial capillary plexus parameters: foveal avascular zone (FAZ) area, 3x3mm and 6x6mm macular perfusion density (PD) and vessel density (VD), 4.5x4.5mm peripapillary capillary perfusion density (CPD) and capillary flux index (CFI). Generalized estimating equation analysis was used to account for the inclusion of 2 eyes from the same participant. 29 eyes of 19 patients with FTD and 85 eyes of 48 controls were analyzed. In FTD, 3x3mm macular PD (p = 0.02) and VD (p = 0.02) and CFI (p = 0.01) were reduced compared to controls. There was no difference in average 4.5x4.5mm CPD, RNFL thickness, GC-IPL thickness, CST, SFCT, CVI, FAZ, or 6x6mm VD or PD between FTD and controls (all p > 0.05); however, there was a trend toward lower macular 6x6mm PD and VD in patients with FTD. Decline of peripapillary and macular OCT and OCTA parameters merit further investigation as potential biomarkers for FTD detection. Noninvasive retinal and choroidal imaging may hold promise for earlier detection, and future longitudinal studies will clarify their role in monitoring of FTD.