Genetic susceptibility to optic neuropathy in patients with alcohol use disorder.

BACKGROUND: The pathophysiology of toxico-nutritional optic neuropathies remains debated, with no clear understanding of the respective roles played by the direct alcohol toxicity, smoking and the often associated vitamin deficiencies, which are risk factors for optic neuropathy. Our aim was to investigate genetic susceptibility in patients with bilateral infraclinical optic neuropathy associated with chronic alcohol use disorder. METHODS: This retrospective cohort study included 102 visually asymptomatic patients with documented alcohol use disorder from a French reference center. Optic neuropathy was identified with optical coherence tomography (OCT), after which genetic susceptibility in the group of affected patients was investigated. Genetic testing was performed using panel sequencing of 87 nuclear genes and complete mitochondrial DNA sequencing. RESULTS: Optic neuropathy was detected in 36% (37/102) of the included patients. Genetic testing of affected patients disclosed two patients (2/30, 6.7%) with optic neuropathy associated with pathogenic variants affecting the SPG7 gene and five patients (5/30, 16.7%) who harbored variants of uncertain significance close to probable pathogenicity in the genes WFS1, LOXL1, MMP19, NR2F1 and PMPCA. No pathogenic mitochondrial DNA variants were found in this group. CONCLUSIONS: OCT can detect presence of asymptomatic optic neuropathy in patients with chronic alcohol use disorder. Furthermore, genetic susceptibility to optic neuropathy in this setting is found in almost a quarter of affected patients. Further studies may clarify the role of preventative measures in patients who might be predisposed to avoidable visual loss and blindness.

Recent advances in the use of optical coherence tomography in neuro-ophthalmology: A review.

Optical coherence tomography (OCT) is an in vivo imaging modality that provides non-invasive, high resolution and fast cross-sectional images of the optic nerve head, retina and choroid. OCT angiography (OCTA) is an emerging tool. It is a non-invasive, dye-free imaging approach of visualising the microvasculature of the retina and choroid by employing motion contrast imaging for blood flow detection and is gradually receiving attention for its potential roles in various neuro-ophthalmic and retinal conditions. We will review the clinical utility of the OCT in the management of various common neuro-ophthalmic and neurological disorders. We also review some of the OCTA research findings in these conditions. Finally, we will discuss the limitations of OCT as well as introduce other emerging technologies.

Longitudinal in vivo evaluation of retinal ganglion cell complex layer and dendrites in mice with experimental autoimmune encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE), induced by the immunization of myelin oligodendrocyte glycoprotein (MOG), is related to human MOG antibody-associated disease (MOGAD). Neuroinflammation and demyelination of the optic nerve can lead to retinal ganglion cell (RGC) death and axonal damage in MOGAD. Here, we aimed to evaluate the structural changes in RGCs longitudinally by in vivo imaging in mice with RGCs expressing yellow fluorescent protein along the course of EAE. Successful induction of EAE was confirmed by the neurological function scores and histology analyses. The changes in the thickness of ganglion cell complex (GCC) layer and RGC survival and dendrites were monitored longitudinally along the course of EAE. Before the onset of EAE, there were no significant changes in the number and morphology of RGCs and the thickness of the GCC layer as compared to the mice without EAE induction. After the onset of EAE, the thickness of the GCC layer and the RGC number and dendritic network all gradually decreased along the course of EAE. Notably, dendritic shrinkage could be detected earlier than the thinning of the GCC layer. In summary, this study delineated the longitudinal profile of RGC structural changes in EAE mice, providing an assessment platform for monitoring outcomes of RGC treatments.

The spatial-temporal reactive changes of compressed optic nerve in a clinically relevant rabbit model of persistent compressive optic nerve axonopathy.

The optic nerve (ON) can get compressed in different diseases. However, the pathological and functional changes occurring in the compressed ON over time under constant compression are still unclear. In the present study, we implanted an artificial tube around the optic nerve of a rabbit to primarily create a clinically relevant persistent compressive optic nerve axonopathy (PCOA). Due to the protuberance on the inner ring of the tube, steady and persistent compressions were maintained. In this model, we investigated the thickness of ganglion cell complex (GCC), retinal ganglion cell (RGC) density, axon density of optic nerve, flash visual evoked potential (FVEP), and anterograde axonal transport at various times in four different groups viz. the no comp, 1/2 comp, 3/4 comp, and crush groups. The GCC thickness, RGC density, and axon density of ON were hierarchically and significantly decreased in 1/2 comp, 3/4 comp, and crush groups. Compared to no comp eyes, the P2 amplitude ratio of FVEP was significantly decreased in 3/4 comp but not in 1/2 comp eyes. Only a portion of the optic nerve lost the ability of anterograde axonal transport in the 1/2 comp group. However, it was evident at 2-wpo and more prominent at 4-wpo in 3/4 comp eyes. This study reveals that the compression only induces the homolateral ON axons impairment and the proportion of the affected axons maintains the same for mild compression for at least three months. Furthermore, an underlying threshold effect highlights that mild compression does not require urgent surgery, while the severe compression warrants immediate surgical intervention.

Retinal functional and structural changes in patients with Parkinson's disease.

BACKGROUND: Visual dysfunction have been well reported as one of the non-motor symptoms in Parkinson's disease (PD). The aim of this study was to evaluate the functional and structural changes in the retina in patients with PD, and to correlate these changes with disease duration and motor dysfunction. METHODS: For this case-control study, we recruited patients fulfilling the diagnostic criteria for idiopathic PD according to British Brain Bank criteria, aged between 50 and 80 years. Age- and sex-matched healthy controls aged between 50 and 80 years were also recruited. Motor function for PD patients was assessed using Modified Hoehn and Yahr staging scale (H & Y staging) and Unified Parkinson's Disease Rating Scale (UPDRS). Optical Coherence Tomography (OCT) and full field electroretinogram (ff-ERG) were done to all participants. RESULTS: Data from 50 patients and 50 healthy controls were included in the analysis. Patients with idiopathic Parkinson's had significantly reduced peripapillary retinal nerve fiber layer (RNFL) thickness and macular ganglion cell complex (GCC) thickness compared to healthy controls (P-value < 0.05 in all parameters). They also had significantly delayed latency and reduced amplitude in both dark-adapted rods and the light-adapted cone for both a & b waves compared to healthy controls (P-value < 0.001 in all parameters). There were statistically significant negative correlations between disease duration, and left superior, right inferior and right & left average RNFL thickness [(r) coef. = -0.327, -0.301, -0.275, and -0.285 respectively]. UPDRS total score was negatively correlated with the amplitude of light-adapted of both RT and LT a & b wave and with dark-adapted RT b-wave latency [(r) coef. = -0.311, -0.395, -0.362, -0.419, and -0.342]. CONCLUSION: The retinal structure and function were significantly affected in patients with PD in comparison to healthy controls. There was a significant impact of disease duration on retinal thickness, and there was a significant negative correlation between the degree of motor dysfunction in patients with PD and retinal function.

Quantification of retinal ganglion cell loss in patients with homonymous visual field defect due to stroke.

BACKGROUND: To quantify the degree of ganglion cell degeneration through spectral domain optical coherence tomography (SD-OCT) in adult patients with post-stroke homonymous visual field defect. METHODS: Fifty patients with acquired visual field defect due to stroke (mean age = 61 years) and thirty healthy controls (mean age = 58 years) were included. Mean deviation (MD) and pattern standard deviation (PSD), average peripapillary retinal nerve fibre layer thickness (pRNLF-AVG), average ganglion cell complex thickness (GCC-AVG), global loss volume (GLV) and focal loss volume (FLV) were measured. Patients were divided according to the damaged vascular territories (occipital vs. parieto-occipital) and stroke type (ischaemic vs. haemorrhagic). Group analysis was conducted with ANOVA and multiple regressions. RESULTS: pRNFL-AVG was significantly decreased among patients with lesions in parieto-occipital territories compared to controls and to patients with lesions in occipital territories (p = .04), with no differences with respect to stroke type. GCC-AVG, GLV and FLV differed in stroke patients and controls, regardless of stroke type and involved vascular territories. Age and elapsed time from stroke had a significant effect on pRNFL-AVG and GCC-AVG (p < .01), but not on MD and PSD. CONCLUSIONS: Reduction of SD-OCT parameters occurs following both ischaemic and haemorrhagic occipital stroke, but it is larger when the injury extends to parietal territories and increases as time since stroke increases. The size of visual field defect is unrelated to SD-OCT measurements. Macular GCC thinning appeared to be more sensitive than pRNFL in detecting retrograde retinal ganglion cell degeneration and its retinotopic pattern in stroke.

Clinical Observation of Macular Superficial Capillary Plexus and Ganglion Cell Complex in Patients with Parkinson's Disease.

INTRODUCTION: We investigated macular superficial capillary plexus (SCP) density and the thicknesses of the ganglion cell complex (GCC) in patients with Parkinson's disease (PD) and correlated them. We also observed the correlations between SCP density and clinical parameters of PD patients. The retina might be a novel biomarker of PD and will be useful in the future for the early diagnosis of PD and detecting disease progression. METHODS: Seventy-four participants (38 patients with PD and 36 healthy controls) were recruited at the Affiliated Hospital of Xuzhou Medical University between January 2022 and June 2022 in this study. The macular SCP densities was measured by optical coherence tomography angiography (OCTA), and the GCC thickness was measured by optical coherence tomography (OCT). The parameters were compared between PD patients and healthy controls. The correlation between SCP and clinical parameters was tested. RESULTS: Compared with the control group, PD patients showed reduced SCP densities in all areas of the macular region (parafovea-temporal: t = 3.053, p = 0.003; parafovea-superior: t = 3.680, p = 0.001; parafovea-nasal: t = 4.643, p < 0.001; parafovea-inferior: t = 2.254, p = 0.027; perifovea-temporal: t = 3.798, p < 0.001; perifovea-superior: t = 3.014, p = 0.004; perifovea-nasal: t = 2.948, p = 0.004; perifovea-inferior: t = 3.337, p = 0.021). The average GCC thickness in the PD patients was significantly reduced (t = 2.365, p = 0.021). There were positive correlations between the average GCC thickness and the SCP densities in most of the areas of the macular regions in PD patients (parafovea-temporal: r = 0.325, p = 0.005; parafovea-superior: r = 0.295, p = 0.011; parafovea-nasal: r = 0.335, p = 0.003; perifovea-superior: r = 0.362, p = 0.002; perifovea-nasal: r = 0.290, p = 0.012; perifovea-inferior: r = 0.333, p = 0.004). We found significant correlations between SCP densities and Hoehn and Yahr (H and Y) scales, UPDRS III scores, and MMSE scores. No significant correlation was observed between SCP density and PD disease duration (all p > 0.05). CONCLUSIONS: We demonstrated that the macular SCP density was decreased, and the average GCC thickness was reduced in PD patients. The correlation between SCP density damage and GCC thinning also suggested that the retinal microvascular damage may be associated with retinal structural degeneration in PD patients. OCTA and OCT may be considered objective biomarkers for detecting microvascular impairment and neuronal damage in the early stages of PD in the future.

Changes of Optic Disc and Macular Vessel Perfusion Density in Primary Angle Closure Glaucoma: A Quantitative Study Using Optical Coherence Tomography Angiograph.

INTRODUCTION: This study aims to investigate the changes of retinal vascular system in primary angle closure glaucoma (PACG) and acute primary angle closure (APAC) by optical coherence tomography (OCT) angiograph (OCTA) and to evaluate the diagnostic ability of changes of vessel density (VD) in different sectors and layers of optic disc and macular area in APAC and PACG. METHODS: In this cross-sectional, observational study, 21 APAC patients (22 eyes) and 21 PACG patients (27 eyes) along with 17 healthy people were enrolled from August 2018 to March 2019. Optic disc region and macular region were imaged using swept-source OCTA system. VD of the macular region was quantified by Image J (1.52a, USA) and Matlab 2018a. The circumpapillary retinal nerve fiber layer (cpRNFL) thickness and ganglion cell complex thickness were obtained by spectral-domain OCT. RESULTS: Compared with the healthy group, the cpRNFL thickness in superior sector was thicker in the APAC group, and this area had the most diffuse microvascular dropout as well. The difference in the macular superficial capillary plexus (SCP) VD between APAC and the control group was not statistically significant. The area under the ROC curves (AUC) of the total optic disc VD in the radial peripapillary capillary (RPC) layer was higher than the AUC of the papillary VD in the optic nerve head (ONH) layer. Compared to the control group, the total optic disc VD, peripapillary VD, and each quadrant of peripapillary VD were decreased in PACG (p < 0.01). In PACG macular region, SCP VD, and deep capillary plexus (DCP) VD, parafovea VD (except temporal sectors) decreased (p < 0.01). The PACG eyes had a greater decrease percentage of VD in total ONH than total macula. The diagnostic value of the VD in the ONH layer and the RPC layer was similar. The diagnostic value of the SCP VD in the macula was greater than the DCP VD in the macula. The AUC was no significant difference between cpRNFL thickness and the total optic disc VD AUC. CONCLUSION: Elevated intraocular pressure preferentially affects vascular perfusion in the optic disc region more than the macular region in APAC and PACG. In the APAC eyes, there was a perfusion defect in the optic disc region and an increase in RNFL thickness. In this study, the OCTA vascular parameters have similar performance to the OCT structural parameters for glaucoma diagnosis in PACG.

Retinal thinning in phenylketonuria and Gaucher disease type 3.

PURPOSE: Retinal alterations in inherited metabolic diseases associated with neurodegeneration are poorly studied. The objective was to study retinal thickness, specifically the components of the ganglion cell complex (GCC)-nerve fiber layer (NFL), ganglion cell layer (GCL), and inner plexiform layer (IPL)-using spectral-domain optical coherence tomography (SD-OCT) in two different diseases with potential dopaminergic depletion, phenylketonuria (PKU) and Gaucher disease type 3 (GD3). METHODS: Retinal layers in 19 patients with PKU, 15 patients with GD3, and 93 healthy individuals were measured using peripapillary ring scan and macular SD-OCT. Linear mixed models were computed including an adjustment for age, sex, and spherical equivalent. We calculated Spearman's rank correlations between retinal layer measurements and clinical and/or laboratory parameters. RESULTS: Thinning of total retinal thickness was found in the macular inner ring (p = 0.002), and outer ring (p = 0.012), sparing the fovea (p = 0.12) in PKU, while in GD3, all subfields were thinned (fovea p < 0.001, inner ring p = 0.047, outer ring 0.07). In both conditions, thinning was most evident in the NFL, GCL, and IPL, while OPL (outer plexiform layer) was thickened. Peripapillary retinal nerve fiber layer measurements remained normal. GCL and IPL in PKU correlated with tyrosine serum concentration. CONCLUSION: Thinning of the NFL, GCL, and IPL, with thickened OPL, are both found in PKU and in GD3. Low dopamine concentrations in the retina might promote these effects. However, these data do not give evidence that retinal measurements can be used as a biomarker for disease severity in patients with GD3.

Changes of retinal ganglion cell complex after vitrectomy in rhegmatogenous retinal detachment patients and its correlation with inflammatory blood biomarkers.

PURPOSE: To compare retinal ganglion cell complex (GCC) parameters between rhegmatogenous retinal detachment (RRD) eyes and normal contralateral eyes after vitrectomy and to evaluate their correlation with inflammatory blood markers. METHODS: We investigated 25 eyes that underwent vitrectomy due to RRD. Venous blood samples were collected from all participants before 08:00 a.m. on the second day of admission after a 12-hour fast for blood counts. The differences of retinal structure between RRD and contralateral eyes were compared 1 week postoperatively. RESULTS: Focal loss volume (FLV) (2.009 ± 1.286)% was significantly increased compared with the contralateral eyes (p <  0.001). Monocyte-to-high-density lipoprotein was significantly positively correlated with GCC thickness parameters, and negatively correlated with FLV and global loss volume (GLV). Postoperative best-corrected visual acuity was negatively correlated with GLV (p = 0.039, R2 = 0.172). CONCLUSION: Retinal ganglion cells (RGCs) loss might present early postoperatively in RRD eyes, and was associated with systemic inflammation. RGCs loss might affect postoperative vision.

Quantitative analysis of related parameters of retinal nerve fiber layer and ganglion cell complex thickness in patients with different degrees of Parkinson's disease.

OBJECTIVE: A quantitative analysis was performed to evaluate the morphologic changes of the retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) in patients with Parkinson's disease (PD). METHODS: Thirty PD patients were enrolled, and they were allocated to the mild-to-moderate PD group (n = 15) or severe PD group (n = 15) according to the severity of PD. Twenty healthy volunteers (20 eyes) were included as controls. Optical coherence tomography (OCT) was used to measure the thickness of mean RNFL and each of the sectors: temporal-upper (TU), superior-temporal (ST), superior-nasal (SN), nasal-upper (NU), nasal-lower (NL), inferior-nasal (IN), inferior-temporal (IT), temporal-lower (TL). The thickness of macular GCC, superior GCC, and inferior GCC was also measured. RESULTS: No difference was found between the three groups with respect to age, sex and disease course (p > 0.05). The mean RNFL thickness was 118.15 ± 10.25 µm in the control group, 96.12 ± 9.45 µm in the mild-to-moderate PD group, and 80.48 ± 10.35 µm in the severe PD group. Significant differences were found in the mean RNFL thickness and thickness of TU, IN, IT and TL sectors among the three groups (p < 0.05). These values, mean RNFL, TU, IN, IT, and TL, were lower in both the PD groups than those in the control, among them the severe PD group had the lowest values. A quantitative analysis of the macula GCC was also performed. Overall, there were significant differences in mean macula, superior, and inferior GCC thickness among the three groups (p < 0.05). The two PD groups had lower values of mean macula, superior, and inferior GCC thickness than that in the controls (p < 0.05); and the severe PD group had lowest values of these parameters. CONCLUSION: In this study, significant thinning of RNFL and macular GCC was found in PD patients. The more serious the illness, the more the thickness becomes thinner. The OCT measurement was found useful in detecting the structural alterations in the retina of PD. The technique may be useful in follow-up of the disease progression after further validation.

Correlation of optical coherence tomography and Doppler ultrasonography findings in pseudoexfoliation syndrome.

PURPOSE: We aimed to investigate the correlation between the color Doppler imaging (CDI) results and parameters determined by spectral domain optical coherence tomography (SD-OCT) in cases with pseudoexfoliation syndrome (XFS). METHODS: 99 participants were included in this prospective study. Retinal nerve fiber layer (RNFL), ganglion cell complex (GCC), optic nerve head (ONH) measurements were recorded. Perfusions of the ophthalmic artery (OA) and central retinal artery (CRA) were determined and resistivity indices (RI) were calculated. RESULTS: No statistically significant differences were determined between the groups regarding the RNFL and ONH parameters. Only the minimum GCC thickness value was determined to be reduced in XFS group (n = 49) when compared to the controls (n = 50) (p = 0.018). The OA-RI and CRA-RI values of XFS group were significantly higher than the control group (p < 0.001 and p = 0.001). In XFSs, negative correlations were present between OA-RI and the minimum, average, inferior and inferotemporal regions of GCC thickness (r = - 0.448 p = 0.001, r = - 0.275 p = 0.040, r = - 0.295 p = 0.027, r = - 0.304 p = 0.024, respectively), and also between CRA-RI and minimum GCC values (r = - 0.317, p = 0.017). While a significant relationship was present between age and OA-RI and CRA-RI values in controls, no such correlation was present in XFSs. CONCLUSIONS: The vascular resistance increased with age in controls, whereas it was independent of age in XFS group. In XFSs, RIs correlated significantly with certain GCC values, but not with RNFL and ONH parameters. It would be beneficial to follow the XFS with CDI as it provides supportive parameters to GCC in order to recognize early changes in XFS.

Ganglion Cell Complex Parameters in Primary Angle Closure Suspects.

INTRODUCTION: This study aimed to investigate the ganglion cell complex (GCC) parameters in primary angle closure suspects (PACS) and identify the related factors. METHODS: A total of 731 subjects, including 289 subjects with PACS and 442 subjects without PACS, underwent RTVue XR OCT. GCC parameters were compared between the two groups. The linear mixed-effects model was performed to evaluate the relationships between the GCC parameters and related factors. RESULTS: Significant differences were found in gender, age, spherical refractive error, height, waist, anterior chamber depth, lens thickness, axial length, superior GCC thickness, ganglion cell complex focal loss volume, ganglion cell complex global loss volume, and ganglion cell complex root mean square between PACS and normal controls. The linear mixed-effects model showed that age (p = 0.008) and blood glucose (p = 0.001) were negatively correlated with average GCC thickness in PACS subjects, and PACS (p = 0.036) and age (p < 0.001) were the key influencing factors for average GCC thickness. CONCLUSION: GCC parameters in PACS subjects are different from those in normal controls. Careful explanation should be considered when evaluating changes of GCC parameters in patients with PACD.

Evaluation of practices of macular ganglion cell complex scan in early detection of glaucoma.

The purpose of this survey was to evaluate the level of awareness and practices regarding macular ganglion cell complex (GCC) scans for early detection of glaucoma. The study design was descriptive cross-sectional and the sampling technique was non-probability convenient method. Data was collected through an online survey, from 100 practicing ophthalmologists and optometrists of Pakistan in two weeks, from January 20 to February 03 2019. Data were analysed using Microsoft Excel 2016. From the results it is strongly evident that significant number of respondents recorded the retinal nerve fibre layer (RNFL) to be the first layer affected as glaucoma progresses, which depicts lack of knowledge among eye care practitioners. Furthermore, both the groups (ophthalmologists and optometrists), used macular GCC scan the least as compared to the RNFL (optic nerve head) scan and visual field tests for early diagnosis of glaucoma. It demonstrated lack of knowledge and practices of macular GCC scan for glaucoma among eye care practitioners.

Long-term effects of trabeculectomy in primary open-angle glaucoma on segmented macular ganglion cell complex alterations.

PURPOSE: The aim of this study is to compare, using optical coherence tomography (OCT), the changes in the thickness of the macular nerve fiber layer (mNFL), macular ganglion cell layer (mGCL), macular inner plexiform layer (mIPL) and peripapillary global retinal nerve fiber layer (gRNFL) (in a span of 3 years) in surgically treated eyes with primary open-angle glaucoma (POAG). METHODS: The medical records of 32 consecutive POAG patients who underwent trabeculectomy with mitomycin-C, between January 2013 and December 2014, were retrospectively reviewed. Pre- and postoperative measurements of IOP and OCT were analyzed 1, 2 and 3 years after the operation. RESULTS: Among all patients, no significant changes in the thickness of the mNFL, mGCL or mIPL were found, with a significant reduction observed only in the IOP values and peripapillary gRNFL thickness during the 3-year postoperative period. In a subgroup analysis based on the preoperative peak IOPs (median value:41 mmHg), the thickness of the mNFL, mGCL and mIPL in the 3-year postoperative period increased significantly in the lower preoperative peak IOP group (IOP < 41 mmHg), whereas the macular OCT parameters in the 3-year postoperative period decreased in the higher preoperative peak IOP group. CONCLUSIONS: Eyes exhibiting lesser preoperative peak IOP demonstrated greater preservation of the layer-by-layer segmented macular ganglion cell complex thickness as compared to eyes exhibiting greater preoperative peak IOP; also when the IOPs determined for the two groups in the period of follow-up were quite comparable.

Macular pigment optical density change analysis in primary open-angle glaucoma and pseudoexfoliation glaucoma.

PURPOSE: We aimed to investigate whether macular pigment optical density (MPOD) has a diagnostic value by comparing MPOD and retinal nerve fiber layer (RNFL), ganglion cell layer++ (GCL++) of patients with primary open-angle glaucoma (POAG) and pseudoexfoliation (PEX) glaucoma and normal individuals. METHODS: We included in the study 54 eyes of 34 patients with diagnosis POAG, 40 eyes of 25 patients with PEX glaucoma and 40 eyes of 20 normal individuals. The MPOD measurements of the cases were performed in the MPOD mode of the fundus fluorescein angiography (Carl Zeiss Visucam Meditec, Germany) device while the pupils were in dilated status. RNFL and GCL++ measurements of all individuals included in the study were done by swept source optical coherence tomography (DRI Triton swept source optical coherence tomography; Topcon, Tokyo, Japan). Intraocular pressures of all three groups were measured by Applanation tonometer. The relationship between MPOD, RNFL and GCL++ values were examined. Patients with additional ophthalmic disease, intraocular surgery, history of chronic drug use, and smokers were excluded in the study. RESULTS: MPOD mean and MPOD max values were significantly higher in patients with PEX glaucoma than POAG and control group (p < 0.05). MPOD mean and MPOD max measurements were not different when compared to POAG patients and control group (p > 0.05). RNFL and GCL++ measurements were found significantly thinner in patients with POAG and PEX glaucoma compared to the control group (p < 0.001). There was no correlation between MPOD values and RNFL or GCL++. MPOD max values show a very high correlation with age in a statistically significant positive direction (r = 0.90, p < 0.001). The average age of PEX glaucoma group was higher than the control group (p = 0.006). There was no age difference between the PEX glaucoma group and the POAG group (p > 0.05). Also, there was no difference in age between POAG and control groups. In POAG and PEX glaucoma groups, mean intraocular pressure values are significantly higher than the control group. CONCLUSIONS: In our study, no MPOD change was observed in the POAG group, while a statistically significant increase in MPOD was found in the PEX glaucoma group. As a result of these findings, we think that PEX syndrome also affects the posterior segment. Well-organized, large, prospective, and randomized studies should be developed for preventive treatment to the negative effects of PEX syndrome on all eye tissues.

Optical coherence tomography indices for diagnosis of chronic glaucoma in patients with diabetes mellitus: a pilot study.

PURPOSE: To evaluate optical coherence tomography (OCT) parameters in patients with concomitant type-2 diabetes mellitus (DM) and primary open angle glaucoma (POAG) compared with patients with either of these diseases. METHODS: Sixty eyes (52 patients) were divided into three groups. The first group included nonglaucomatous diabetic patients, the second included patients with POAG without DM, and the third included patients with both POAG and DM. Spectral domain OCT evaluation of the retinal nerve fiber layer (RNFL), ganglion cell complex (GCC), and optic disc parameters was performed. Visual field (VF) was measured for structural and functional correlation. RESULTS: Significant differences were found in average RNFL, inferior RNFL, average GCC, inferior GCC, rim area, focal loss volume (FLV%), and global loss volume (GLV%) (P = 0.014, 0.001, 0.027, 0.006, 0.009, 0.043, and 0.001, respectively). The concomitant presence of DM and glaucoma was a risk factor for decreased average RNFL, inferior RNFL, rim area, and inferior GCC, and for increased GLV% (P = 0.034, 0.002, 0.014, 0.015, and 0.003, respectively). The inferior RNFL thickness had the largest significant area under the curve (P = 0.726; 90% sensitivity) at a specificity greater than 80% with a cutoff value of 105.38 µm (P = 0.005) compared with average RNFL, inferior GCC, rim area, and GLV% (P = 0.073, 0.25, 0.23, and 0.1, respectively). VF demonstrated the predominance of nasal scotomata in the diabetic group and arcuate scotoma in the glaucoma group (P < 0.001 and 0.03, respectively). CONCLUSIONS: OCT could be a valuable tool for the detection and follow-up of POAG in diabetic patients. The inferior RNFL thickness could be a sensitive and a specific predictor for glaucoma diagnosis and progression in diabetic patients without retinopathy.

Evaluation of the effect of unilateral late blindness on the retina, optic nerve and choroid parameters in the sighted eye.

BACKGROUND: To investigate whether unilateral late blindness alters the peripapillary retinal nerve fiber layer (RNFL), ganglion cell complex (GCC), central macular thickness (CMT) and choroidal thickness (CT). METHODS: The 17 healthy eyes of 17 monocular patients with late blindness due to isolated eye trauma in one eye and the 19 eyes of 19 healthy individuals were evaluated in this retrospective study. Patients with at least 10 years of monocular blindness, a refractive error between + 1.5 and -1.5 D in the sighted eye, a best-corrected visual acuity of at least 20/20 and an axial length (AL) < 25 mm were included in the study. Following ophthalmologic examination, the RNFL, GCC, CMT and CT values were measured with spectral domain optic tomography (SD-OCT). Those with ocular, systemic or neurological disease that could influence the measured parameters were excluded from the study. RESULTS: A total of 17 (14 males, 3 females) monocular patients [mean age 41.00 ± 11.95 (24-64)] and 19 (16 males, 3 females) healthy individuals [mean age 39.79 ± 6.74 (30-56)], similar in age and gender (p = 0.949 and p = 0.881), were included in the study. The mean duration of being monocular was 22.76 ± 11.76 (10-49) years. No difference was present between the RNFL, GCC, CMT and CT measurements of the monocular patients and the healthy individuals (p = 0.692, p = 0.294, p = 0.113, p = 0.623, respectively). No significant correlation was found between the duration of monocularity and the retinal and optic nerve parameters. CONCLUSION: The results of our study indicate no difference in the optic nerve, retina and choroid OCT findings in the sighted eyes of subjects with long-term monocular blindness compared to subjects with bilateral normal eyes. Although functional and volumetric neuroimaging studies suggest the possibility of compensation in these patients, our findings indicate that this is not at the ocular level.

Optical coherence tomography indices in the diagnosis and discrimination of stages of primary open-angle glaucoma in an African population.

PURPOSE: The objective of this study was to determine the structure-function association of the optical coherence tomography (OCT) indices (retinal nerve fibre layer (RNFL), ganglion cell complex (GCC) and optic nerve head (ONH) parameters) with the visual field sensitivity and their diagnostic ability at different stages of primary open-angle glaucoma (POAG) among a population West-African descent. METHODS: The study was a clinic-based prospective study which employed purposive sampling in the recruitment of clinically diagnosed POAG and non-glaucoma patients. OCT and visual field test (VFT) results were collated. Classification of the POAG cases was done using the Hodapp-Parrish-Anderson criteria. ROC was used for assessing the diagnostic ability of OCT indices. Pearson's correlation was used to assess the structure-function association. P value < 0.05 was considered statistically significant. CONCLUSIONS: Of the 497 subjects (497 eyes), 301 (60.6%) were males and 196 (39.4%) were females. The average, superior and inferior RNFL and GCC showed a strong positive correlation with the visual field sensitivity, but the average RNFL had the highest correlation (r = 0.673, p < 0.001). The parameters of the ONH showed a moderate-to-weak correlation with the visual field sensitivity. However, there was no significant correlation between structure and function in early POAG (p > 0.05). Superior GCC showed the highest diagnostic ability for POAG (AUC = 0.655; p < 0.001) comparable to the RNFL. Macula (GCC) and (RNFL) have a comparable ability to diagnose POAG at all the stages of POAG and can be used complimentarily for glaucoma assessment and diagnosis.

Ganglion Cell Complex Thinning in Young Gaucher Patients: Relation to Prodromal Parkinsonian Markers.

BACKGROUND: Patients with Gaucher disease (GD) have an increased risk for parkinsonism. Retinal thinning has been described in parkinsonism as an early nonmotor feature. Scarce reports have addressed retinal thickness changes in GD. OBJECTIVES: The objectives of this study were to compare ganglion cell complex (GCC) thickness in adolescents and young adults (AYAs) with GD with healthy control subjects, and to correlate it with the presence of parkinsonian features (PFs), clinical prodromal markers of parkinsonism, severity score index (SSI), and glucosylsphingosine (Lyso-GL-1). METHODS: This study included 48 AYAs with GD (11-29 years), 11 with manifest PFs (Group 1) and 37 with no PFs (Group 2), and 48 matched healthy control subjects (Group 3). Age of GD onset, disease duration, medication history, history of constipation, SSI, and hematological assessment were done. Neurocognitive evaluation included Parts I, II, and III of the Unified Parkinson's Disease Rating Scale (UPDRS), Wechsler Adult and Intelligence Scale and Wechsler Intelligence Scale for Children, Beck Depression Inventory (BDI), rapid eye movement sleep behavior disorder (RBD) scale, Munich Parasomnia Screening scale, and the olfactory dysfunction scale. Molecular analyses of the acid GBA gene and Lyso-GL-1 were done. Participants underwent full ophthalmological examination and optical coherence tomography with GCC thickness measurement. RESULTS: GCC was significantly thinner in Group 1 than in Groups 2 and 3 (P < 0.001), whereas no significant difference was found between Groups 2 and 3 (P = 0.977). In addition, a significant interocular GCC thickness difference was found among the studied AYAs with GD (P = 0.007). GCC correlated positively with total intelligence quotient (P < 0.001) and negatively with Lyso-GL-1 (P = 0.019), UPDRS (P = 0.004), and BDI (P = 0.029), but not with SSI (P = 0.874), GD type (P = 0.85), or genotype (P = 0.842). A significant negative relationship was found between GCC thickness and PFs (P = 0.001), parasomnia (P = 0.003), constipation (P = 0.031), RBD (P = 0.044), and hyposmia (P = 0.033). CONCLUSIONS: GCC thinning may be a promising biomarker for central nervous system neurodegeneration that has the potential to monitor early PFs among people with GD. © 2020 International Parkinson and Movement Disorder Society.