Nerve Fiber Layer Research Articles

Could the thick of retinal nerve fiber layer be a potential measure of axonal loss in hearing loss?

Could the thick of retinal nerve fiber layer be a potential measure of axonal loss in hearing loss?

Measurement of the Tilt Angle of the Optic Disc Using Spectral-Domain Optical Coherence Tomography and Related Factors in Myopia.

This study presents a novel, three-dimensional method for measuring the tilt angle of the tilted optic disc (TOD) using spectral-domain optical coherence tomography (SD-OCT) and investigates the correlation between ocular-related parameters and TOD. We included the right eyes of 243 healthy young individuals, categorized by axial length. We measured the ovality index (OI) and dihedral angle (DA) using SD-OCT infrared ray fundus photographs and high-resolution cross-sectional images of the optic disc, respectively. The relationships between OI, DA, and ocular-related parameters were analyzed. Eyes in the longer axial length group exhibited a lower OI and a higher DA, along with thinner nasal and inferonasal circumpapillary retinal nerve fiber layer (cpRNFL) and thicker temporal and superotemporal cpRNFL. There was a significant relationship between DA and cpRNFL thickness. The new method utilizing DA to measure the tilt angle of TOD demonstrated high repeatability. We propose a novel, three-dimensional, and quantitative method for evaluating the tilt degree of TOD. A higher degree of myopia indicated a greater tilt angle of the TOD, and a greater TOD suggested additional changes in cpRNFL thickness. These findings should be considered when interpreting increased susceptibility and early assessment of glaucoma in myopia. DA could serve as a superior indicator for describing TOD morphology during eyeball elongation and evaluating its impact on related parameters of the optic disc and peripapillary structures in the myopic population.

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.

Retinal and Corneal OCT Results of Patients Hospitalized and Treated in the Acute Phase of COVID-19.

Objective: This study aimed to assess changes in the morphology of the retina and cornea in patients treated and hospitalized during the acute active phase of SARS-CoV-2 infection. Methods: A total of 24 patients with symptomatic early COVID-19 disease and 38 healthy participants from a control group were enrolled in our study. Among them, 20 received oxygen therapy at flow rates ranging from 1-10 L, while four received high-flow intranasal oxygen therapy (HFNOT). Some patients were treated with other types of therapy, such as Remdesivir, COVID-19 convalescent plasma therapy, or Tocilizumab. In the study, we focused on the analysis of optical coherence tomography (OCT) images of the cornea and retina including corneal thickness, central retinal thickness, retinal nerve fiber layer (RNFL), and optic disc parameters. The measurements were acquired using Spectral-domain OCT REVO FC 130. Results: The analysis did not show significant changes between the examined ophthalmological parameters before and after therapy. Furthermore, there were no detected significant differences between the tested parameters of the retina and cornea in COVID-19-positive patients compared to the control group. Conclusions: No ophthalmological manifestations of COVID-19 disease were observed during the study. Taking into account the results of other publications, the lack of an unambiguous position on this topic requires further research.

Lamina Cribrosa Microstructure in Nonhuman Primates With Naturally Occurring Peripapillary Retinal Nerve Fiber Layer Thinning.

The lamina cribrosa (LC) is hypothesized to be the site of initial axonal damage in glaucoma with the circumpapillary retinal nerve fiber layer thickness (RNFL-T) widely used as a standard metric for quantifying the glaucomatous damage. The purpose of this study was to determine in vivo, 3-dimensional (3D) differences in the microstructure of the LC in eyes of nonhuman primates (NHPs) with naturally occurring glaucoma. Spectral-domain optical coherence tomography (OCT) scans (Leica, Chicago, IL, USA) of the optic nerve head were acquired from a colony of 50 adult rhesus monkeys suspected of having high prevalence of glaucoma. The RNFL-T was analyzed globally and in quadrants using a semi-automated segmentation software. From a set of 100 eyes, 18 eyes with the thinnest global RNFL-T were selected as the study group and 18 eyes with RNFL-T values around the 50th percentile were used as controls. A previously described automated segmentation algorithm was used for LC microstructure analysis. Parameters included beam thickness, pore diameter and their ratio (beam-to-pore ratio [BPR]), pore area and shape parameters, beam and pore volume, and connective tissue volume fraction (CTVF; beam volume/total volume). The LC microstructure was analyzed globally and in the following volumetric sectors: quadrants, central and peripheral lamina, and three depth slabs (anterior, middle, and posterior). Although no significant difference was detected between groups for age, weight, or disc size, the study group had significantly thinner RNFL than the control group (P < 0.01). The study group had significantly smaller global and sectoral pore diameter and larger BPR compared with the control group. Across eyes, the global RNFL-T was associated positively with pore diameter globally. BPR and CTVF were significantly and negatively associated with the corresponding RNFL-T in the superior quadrant. Global and sectoral microstructural differences were detected when comparing thin and normal RNFL-T eyes. Whether these LC differences are the cause of RNFL damage or the result of remodeling of the LC requires further investigation. Our findings indicate structural alterations in the LC of NHP exhibiting natural thinning of the RNFL, a common characteristic of glaucomatous damage.

Retinal ischemia-reperfusion injury and pretreatment with Lycium barbarum glycopeptide.

To investigate the antioxidant protective effect of Lycium barbarum glycopeptide (LbGP) pretreatment on retinal ischemia-reperfusion (I/R) injury (RIRI) in rats. RIRI was induced in Sprague Dawley rats through anterior chamber perfusion, and pretreatment involved administering LbGP via gavage for 7d. After 24h of reperfusion, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine (CREA) levels, retinal structure, expression of Caspase-3 and Caspase-8, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) in the retina were measured. The pretreatment with LbGP effectively protected the retina and retinal tissue from edema and inflammation in the ganglion cell layer (GCL) and nerve fiber layer (NFL) of rats subjected to RIRI, as shown by light microscopy and optical coherence tomography (OCT). Serum AST was higher in the model group than in the blank group (P=0.042), but no difference was found in ALT, AST, and CREA across the LbGP groups and model group. Caspase-3 expression was higher in the model group than in the blank group (P=0.006), but no difference was found among LbGP groups and the model group. Caspase-8 expression was higher in the model group than in the blank group (P=0.000), and lower in the 400 mg/kg LbGP group than in the model group (P=0.016). SOD activity was lower in the model group than in the blank group (P=0.001), and the decrease was slower in the 400 mg/kg LbGP group than in the model group (P=0.003). MDA content was higher in the model group than in the blank group (P=0.001), and lower in the 400 mg/kg LbGP group than in the model group (P=0.016). The pretreatment with LbGP did not result in any observed liver or renal toxicity in the model. LbGP pretreatment exhibits dose-dependent anti-inflammatory, and antioxidative effects by reducing Caspase-8 expression, preventing declines of SOD activity, and decreasing MDA content in the RIRI rat model.

Retinal nerve fiber layer defects and chronic kidney disease: the Kailuan Eye Study.

To investigate whether retinal nerve fiber layer defects (RNFLDs) is a potential risk factor for chronic kidney disease (CKD) in Chinese adults. The Kailuan Eye Study was a population-based study that included 14 440 participants. All participants underwent detailed assessments, RNFLDs were diagnosed using color fundus photographs. Overall, 12 507 participants [8533 males (68.23%)] had complete systemic examination data and at least one evaluable fundus photograph. RNFLDs were found in 621 participants [5.0%; 95% confidence interval (CI): 4.6%-5.34%], and 70 cases of multiple RNFLDs were found (11.27%). After adjusting multiple factors, RNFLDs was significantly associated with CKD severity, the ORs of CKD stage 3, stage 4 and stage 5 were 1.698, 4.167, and 9.512, respectively. Multiple RNFLDs were also associated with CKD severity after adjusting multiple factors, the ORs of CKD stage 3 and stage 5 were 4.465 and 11.833 respectively. Furthermore, 2294 participants had CKD (18.34%, 95%CI: 17.68%-18.99%). After adjusting for other factors, CKD presence was significantly correlated with the presence of RNFLDs. The strongest risk factors for RNFLDs are CKD and hypertension. Conversely, RNFLDs can be an ocular feature in patients with CKD. Fundoscopy can help detect systemic diseases, and assessment for RNFLDs should be considered in CKD patients.

Retinal nerve fiber layer thickness and radial peripapillary capillaries density in myopic adults with optical coherence tomography angiography

PurposeTo evaluate retinal nerve fiber layer thickness (RNFLT) and radial peripapillary capillaries (RPC) density in adults with different degrees of myopia using optical coherence tomography angiography (OCTA) and explore their relationship with ocular factors, such as axial length (AL) and disc area.MethodsA total of 188 subjects were included in this cross-sectional study. The eyes were divided into four groups according to AL. OCTA was used for the assessment of RNFLT, RPC density, and other optic disc measurements, such as disc area. One-way analysis of variance was performed to compare differences between four groups, and P value < 0.01 was considered significant.ResultsThe RNFLT was significantly thinner in high myopia (HM) group at inferior nasal (IN) quadrant (P = 0.004) than low myopia (LM) group, but thicker at temporal inferior (TI) quadrant (P = 0.006). The RPC density of nasal superior (NS) quadrant, nasal inferior (NI) quadrant, and inferior nasal (IN) quadrant significantly decreased as AL increasing. By simple linear regression analysis, the inside disc RPC (iRPC) density tended to be correlated significantly with AL (0.3997%/mm, P < 0.0001). Peripapillary RPC (pRPC) density was in significant correlation with AL (-0.2791%/mm, P = 0.0045), and peripapillary RNFLT (pRNFLT) was in significant correlation with disc area (0.2774%/mm2, P = 0.0001).ConclusionRNFLT and RPC density were closely associated with AL and disc area. They might be new indexes in assessing and detecting myopia development via OCTA.

Assessment of the impact of low-density lipoprotein cholesterol on retinal vessels using optical coherence tomography angiography

BackgroundLow-density lipoprotein cholesterol (LDL-C) is acknowledged as an independent risk factor (IRF) for atherosclerotic cardiovascular disease. Nevertheless, studies on the impact of LDL-C on microvasculature are still scarce. The retina, abundant in microvasculature, can now be examined for microvascular alterations through the novel, non-invasive, and quantitative optical coherence tomography angiography (OCTA) technique.MethodsIn this cross-sectional study, 243 patients from the geriatric department were recruited (between December 2022 and December 2023). Individuals were classified into four groups based on their LDL-C levels: Group 1 (≤ 1.8 mmol/L), Group 2 (> 1.8 mmol/L to ≤ 2.6 mmol/L), Group 3 (> 2.6 mmol/L to ≤ 3.4 mmol/L), and Group 4 (> 3.4 mmol/L). The OCTA results including retinal vessel density (VD), foveal avascular zone (FAZ) area, macula thickness, and retinal nerve fiber layer (RNFL) thickness were contrasted across these groups. T-tests, analysis of variance, Welch’s tests, or rank-sum tests were employed for statistical comparisons. In cases where significant differences between groups were found, post-hoc multiple comparisons or rank-sum tests were performed for pairwise group comparisons. Spearman’s correlation coefficient was employed to perform bivariate correlation analysis to evaluate the relationship between LDL-C levels and various OCTA measurements. Multivariable regression analysis was used to evaluate the association between LDL-C levels and various OCTA measurements. Linear regression analysis or mixed-effects linear models were applied.ResultsIt was discovered that individuals with LDL-C levels exceeding 2.6 mmol/L (Groups 3 and 4) exhibited reduced VD in the retina, encompassing both the optic disc and macular regions, compared to those with LDL-C levels at or below 2.6 mmol/L (Groups 1 and 2). A negative correlation among LDL-C levels and retinal VD was identified, with r values spanning from − 0.228 to -0.385. Further regression analysis presented β values between − 0.954 and − 2.378. Additionally, no notable disparities were detected among the groups regarding FAZ area, macular thickness, and RNFL thickness.ConclusionsThe outcomes of this study suggest that elevated LDL-C levels constitute an IRF for decreased VD across the entire retina.Trial registrationNCT05644548, December 1, 2022.

Analysis of retinal thickness using spectral domain optical coherence tomography in hypertensives and normotensives: A comparative study

: The change in the retinal thickness is the indicator of retinal disease. These changes can be measured with Spectral-domain optical coherence tomography (SD-OCT). This study was conducted to compare the central macular thickness (CMT), retinal nerve fiber layer (RNFL), and ganglion cell inner plexiform layers (GCIPL) thickness using SD-OCT in hypertensive and normotensives.: All patients with systemic hypertension above the age of 18 years were included in Group A and the age-matched normotensive patients in group B. A history of hypertension was obtained and blood pressure was measured. A standard eye examination and retinal imaging were performed using SD-OCT. The main parameters studied were CMT, RNFL, and GCIPL. An odds ratio and t-test were performed. A probability value of &amp;#60;0.05 is considered significant.: There were 60 eyes in each group. The mean age in group A was 52.43±10.35 years. The mean standard deviation of the duration of hypertension in group A was 6.41±6.28 years. The mean standard deviation CMT was 251.03±18.25µm and 256.77±15.09µm in group A and B respectively. There was no statistically significant difference in CMT of hypertensive and normotensives. The hypertensive patients had significant thickening of RNFL in the nasal quadrant compared to normotensive individuals.: The present study supports the concept that CMT is less likely to be influenced by systemic HTN. RNFL thickness may increase in hypertensives compared to normotensives.

A study on correlation between automatedperimetry and optical coherence tomography findings in glaucoma suspects

To evaluate the correlation between optic disc and retinal nerve fiber layer (RNFL) parameters of SD OCT scan of optic disc, and, visual field indices of Humphrey visual field analyzer. This is a prospective, cross-sectional study of 47 patients who are glaucoma suspects. They have been screened for glaucoma by comprehensive ophthalmic examination including visual field testing by automated perimetry and optic nerve head and retinal nerve fiber layer thickness changes assessment by optical coherence tomography. Mean age of the glaucoma suspects was 54.35 ± 10.6 years. Women were having higher (58.7%) mean age as compared to men (41.3%). Mean IOP in glaucoma suspects was 17.97 mmHg. The mean CD ratio was measured as 0.66 ± 0.11 and with significant negative correlation between the mean MD and CD ratio values (p&amp;#60;0.05) and similarly between MD and Vertical CDR. PSD showed significant positive correlation with CDR and also with Vertical CDR. Correlation is noted between MD and average RNFL, with significant positive correlation between MD and superior RNFL. Spectral domain OCT, when used in combination with automated perimetry helps in early diagnosis of glaucoma.SD OCT of Optic disc alone can detect changes of RNFL in patients with normal discs and visual fields. Optic Disc OCT plays a vital role in diagnosing preperimetric glaucoma patients.

Correlation between optical coherence tomography angiography measured vessel density and retinal nerve fiber layer thickness in moderate primary open angle glaucoma cases and normal controls

: Aim of this study was to establish a correlation between findings obtained from Optical Coherence Tomography Angiography (OCT-A) and Retinal Nerve Fiber Layer (RNFL) thickness measurements in a series of moderate Primary Open Angle Glaucoma (POAG) cases and normal controls. In this observational cross-sectional study a total of 100 eyes were included, comprising 50 eyes with glaucoma and 50 control eyes without glaucoma. All participants underwent comprehensive anterior and posterior segment evaluations, intraocular pressure (IOP) measurement using Goldmann applanation tonometer, gonioscopy, visual field testing, and OCT imaging, which included OCT-A. The OCT-A imaging was performed using the RTvue XR Avanti by Optovue. Two types of analysis were conducted: a comparative analysis between the normal and glaucomatous groups using an unpaired t-test to assess differences in RNFL thickness and vessel density values, and a correlation analysis within each group to examine the strength of correlation between RNFL loss and reduction in vascular density. The results showed a significant reduction in vessel density index in all quadrants of glaucomatous eyes compared to normal eyes. Moreover, this reduced vessel density was found to be significantly correlated with the reduction in RNFL thickness in glaucoma patients. Specifically, the uperior and inferior quadrants exhibited the strongest correlation with each other. The severity of vascular compromise demonstrated a significant correlation with the extent of retinal nerve fiber loss in patients with glaucoma. OCT-A can serve as a valuable adjunct in the diagnosis of glaucoma and monitoring its progression.

Alitretinoin-induced Pseudotumor Cerebri: A Case Report

Purpose: We present a case of alitretinoin-induced pseudotumor cerebri.Case summary: A 28-year-old woman presented with a 1-month history of bilateral papilledema and intermittent blurred vision in the left eye. She had been taking alitretinoin (9-cis-retinoic acid, Alitoc&lt;sup&gt;Ⓡ&lt;/sup&gt;; GlaxoSmithKline) for atopic dermatitis and hand eczema. Although visual acuity remained intact in both eyes, mild central scotoma was detected bilaterally. Optical coherence tomography revealed increased retinal nerve fiber layer thickness in both eyes. Enhanced magnetic resonance imaging revealed no abnormalities except for bilateral flattening of the posterior sclera. Cerebrospinal fluid exhibited an elevated opening pressure (220 mmH&lt;sub&gt;2&lt;/sub&gt;O) and a normal composition. Following the discontinuation of alitretinoin, the intermittent blurred vision, papilledema, and central scotoma improved significantly within 2 months.Conclusions: Alitretinoin use should be monitored carefully for a potential development of pseudotumor cerebri, particularly in patients with pre-existing risk factors.mmH2O) and a normal composition. Following

Comparison of retinal nerve fiber thickness in emmetropes, myopes and hyperopes using optical coherence tomography

Aim of this study was to analyze retinal nerve fiber layer thickness by using spectral domen Optical Coherence Tomography (OCT) in different refractive status (emmetrops, myopes and hypermetrops).A cross-sectional study involved 150 patients aged 18-40, with and without refractive errors. Three groups (Emmetropic, Myopic, Hypermetropic) were tested using spectral domain OCT after pupil dilation, comparing RNFL thickness.In this study, 150 participants were categorized into three groups: emmetropia, myopia, and hypermetropia. The age group most represented was 21-25 years, comprising 35.3% of the sample. Of the total, 80 were male (53.3%), and 70 were female. Among males, 22 patients were emmetropia, myopia in 31 and hypermetropia in 27. The mean axial length for emmetropia was 23.54 ± 0.48 SD, myopia was 24.53 ± 0.48 and hypermetropia was 22.36 ± 1.11. Hypermetropia was further categorized into low-grade 22.49 ± 1.06 SD, moderate 22.26 ± 1.12 SD and high-grade 22.45 ± 1.00 based on axial length.Myopic individuals exhibited significant RNFL thinning, particularly in the inferior and superior quadrants, resembling early glaucoma-related changes. This has implications for glaucoma suspect evaluations.

Structural Features of Optic Nerve Head in Glaucoma with Single-hemispheric and Bi-hemispheric Visual Field Defects

Purpose: To compare the structural features of the optic nerve head (ONH) in moderate glaucoma patients with single-hemispheric and bi-hemispheric visual field (VF) defects.Methods: Patients with open-angle glaucoma (OAG) and a VF mean deviation between -6 and -12 dB were retrospectively enrolled. Based on VF defect patterns, eyes were classified into two groups: those with single-hemispheric VF defects and those with bi-hemispheric VF defects. Structural features analyzed included Bruch’s membrane opening area, lamina cribrosa (LC) thickness, temporal β-zone parapapillary atrophy with and without Bruch's membrane (βPPA&lt;sub&gt;+BM&lt;/sub&gt;, βPPA&lt;sub&gt;-BM&lt;/sub&gt;, respectively), and peripapillary retinal nerve fiber layer thickness using spectral-domain optical coherence tomography.Results: Out of 137 eyes from 124 patients, 80 eyes had single-hemispheric VF defects and 57 eyes had bi-hemispheric VF defects. The bi-hemispheric group exhibited longer axial length (&lt;i&gt;p&lt;/i&gt; = 0.038), thinner central corneal thickness (&lt;i&gt;p&lt;/i&gt; = 0.003), thinner LC (&lt;i&gt;p&lt;/i&gt; &lt; 0.001), and larger temporal βPPA&lt;sub&gt;+BM&lt;/sub&gt; (&lt;i&gt;p&lt;/i&gt; = 0.002) compared to the single-hemispheric group.Conclusions: Among Korean OAG patients with moderate VF defects, those with bi-hemispheric VF defects showed more structurally vulnerable optic discs characterized by longer axial lengths, thinner central corneal thickness, thinner LC, and larger β PPA+BM compared to those with single-hemispheric VF defects. These findings underline the importance of evaluating ONH structures in monitoring glaucoma progression particularly in patients with extensive VF damage.

Prevalence of Normal-Tension Glaucoma in Patients With Primary Aldosteronism

PurposeTo investigate patients with primary aldosteronism (PA) and the prevalence of normal-tension glaucoma (NTG). DesignCross-sectional study. MethodsNewly diagnosed PA patients were evaluated in this cross-sectional study, with ophthalmic examinations such as intraocular pressure (IOP) measurements by a Goldmann applanation tonometer, central corneal thickness (CCT), slit-lamp biomicroscopic examination, gonioscopy, ophthalmoscopy, fundus photography, visual field test with a Humphrey Field Analyzer 24-2 SITA Standard program, and optical coherence tomography (OCT) of the peripapillary retinal nerve fiber layer (RNFL), performed in each of the subjects. Optic disc appearance, perimetric results, OCT results, and other ocular findings were all used for determining the glaucoma diagnosis. The primary outcome was shown the prevalence of NTG in patients with PA. ResultsNTG prevalence in the 212 PA patients was 11.8% (95% confidence interval [CI], 4.7%-20.7%). As compared to the hypertensive patients without PA, the hypertensive patients with PA exhibited a significantly increased NTG prevalence (odds ratio; 4.019, 95% CI, 1.223-13.205; P = .022). Increased NTG prevalence was associated with age, ranging from 8.8% (95% CI, 2.1%-15.6%) for those aged 40 to 49 years, to 37.5% (95% CI, 13.8%-61.2%) for those aged 70 years and older. In 72 hypertensive patients without PA, who were used as the controls, NTG prevalence was 5.2%, with a 95% CI ranging from 0.5% to 14.4%. ConclusionsThere was an 11.8% prevalence of NTG in PA patients, with these patients at an elevated risk of NTG, which was not mediated by blood pressure.

Ocular changes in Alzheimer’s disease

Alzheimer&amp;rsquo;s disease (AD) is an incurable, irreversible condition that bears a large global burden. An early diagnosis is imperative to allow the maximum time for treatment interventions. The eye&amp;rsquo;s involvement has been identified in AD, making it a promising option for a non-invasive early diagnostic and screening tool. The pathology of AD observed in the brain such as amyloid beta (A&amp;beta;) plaques and phosphorylated tau have been mirrored in the retina. There is also evidence that AD pathology in the retina precedes the onset of symptoms and the deposition of plaques in the brain. It is estimated that A&amp;beta; burden results in structural changes in the eye such as degeneration of the retinal nerve fiber layer, thinning of the macula, reduced blood flow rate, and thinning of the choroid. These structural changes can be observed using non-invasive imaging techniques such as optical coherence tomography. This review examines the existing literature on AD pathology in the retina and discusses the possibility of using retinal imaging techniques to screen for AD.

The effect of alemtuzumab on neurodegeneration in relapsing-remitting multiple sclerosis: A five-year prospective mono-center study

BackgroundRelapsing-remitting multiple sclerosis (RRMS) is an inflammatory and neurodegenerative disease. After two or more short courses of alemtuzumab (ALZ), an immune reconstitution is achieved, which long-term results in reduced disease activity. We aimed to investigate the effect of ALZ on measures of neurodegeneration (i.e., brain atrophy, and retinal layer thinning). MethodsWe designed an observational prospective mono-center study in RRMS patients initiating ALZ treatment. Patients were assessed at baseline (month 0) and thereafter annually for five years with clinical measures, synthetic magnetic resonance imaging (SyMRI) and optical coherence tomography (OCT), with a re-baseline SyMRI scan and an OCT exam 24 months after initiating ALZ. Persons with neurological symptoms but without evidence of neurological disease served as symptomatic controls (SCs, n = 27). ResultsForty-nine RRMS patients were included. Baseline median expanded disability status scale [2.0 (IQR 1.5)] was unchanged during follow-up, 71 % were progression-free, 33 % achieved no evidence of disease activity-3 (NEDA-3). Between baseline and month 60, SyMRI showed a reduction of brain parenchymal fraction (BPF) and grey matter (GM) volume in patients. The BPF reduction was greater in RRMS patients than in SCs (p < 0.05), and more pronounced in patients with high pre-baseline disease activity than in those without (p < 0.01). OCT showed significant thinning of macular ganglion cell and inner plexiform layers (mGCIPL) and in peripapillary retinal nerve fiber layer (pRNFL) in patients. In contrast, absolute values of white matter (WM) volume and myelin content (MyC) quantified by SyMRI, were stable or increased after re-baseline (month 24) and up to month 60, and this increase appeared limited to patients without high pre-baseline disease activity and to patients with NEDA-3 or disability worsening during follow-up. A strong positive correlation between WM volume and GM volume at baseline was lost after ALZ intervention for their delta values, i.e., change from re-baseline (month 24) to month 60. While the positive baseline correlation between WM volume and MyC increased for their delta values, the positive baseline correlation between GM volume and MyC changed to negative for their delta values. ConclusionWe showed that neurodegeneration continued in RRMS patients under ALZ treatment, but it appeared to be limited to BPF and GM, and more pronounced in patients with disease activity. Our data suggest that patients who respond to ALZ treatment show signs of remyelination. OCT and SyMRI have potential to quantify measures of neurodegeneration that is affected by treatment intervention in RRMS.

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.

Inflammatory Optic Neuropathy

Optic neuritis is the primary inflammation of the optic nerve. Chronic Recurrent Isolated Optic Neuropathy is an inflammatory optic neuropathy characterized by its recurrent and/or chronic nature, as well as corticosteroid sensitivity. Relapses that occur after the reduction or cessation of steroids and more severe visual loss compared to demyelinating optic neuritis are characteristic features. Although patients initially tend to respond well to steroids, cumulative damage can lead to poor visual outcomes and permanent loss of the retinal nerve fiber layer and ganglion cell layer. Diagnosing inflammatory optic neuropathies is crucial, as maintenance immunosuppressive therapy should be initiated in patients with relapses to protect against permanent vision loss in many types.