Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population identification.This study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular status.Methods We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or older.Logistic regression was used to analyze the relationship between retinal metrics and cognitive function.Subgroups stratified by different vascular statuses were also analyzed.Results RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel stenosis.The underlying small vessel change in RNFL and CI should be investigated in the future.

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

AIM:To investigate whether retinal nerve fiber layer defects(RNFLDs)is a potential risk factor for chronic kidney disease(CKD)in Chinese adults.METHODS:The Kailuan Eye Study was a populationbased study that included 14440 participants.All participants underwent detailed assessments,RNFLDs were diagnosed using color fundus photographs.RESULTS:Overall,12507 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.CONCLUSION: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.

Quantifying peripapillary vessel density and retinal nerve fibre layer in type 1 diabetic children without clinically detectable retinopathy using OCTA

AIM:To quantify changes in radial peripapillary capillary vessel density(ppVD)and the peripapillary retinal nerve fiber layer(pRNFL)in children with type 1 diabetes without clinical diabetic retinopathy by optical coherence tomography angiography(OCTA),providing a basis for early retinopathy in children with type 1 diabetes.METHODS:This was a retrospective study.A total of 30 patients(3–14y)with type 1 diabetes without clinical diabetic retinopathy(NDR group)were included.A total of 30 age-matched healthy subjects were included as the normal control group(CON group).The HbA1c level in the last 3mo was measured once in the NDR group.The pRNFL thickness and ppVD were automatically measured,and the mean pRNFL and ppVD were calculated in the nasal,inferior,temporal,and superior quadrants.The changes in ppVD and pRNFL in the two groups were analyzed.RESULTS:Compared with CON group,the nasal and superior ppVDs decreased in the NDR group(all P<0.01).The thickness of the nasal pRNFL decreased significantly(P<0.01),while the inferior,temporal and superior pRNFLs slightly decreased but not significant in the NDR group(all P>0.05).Person and Spearman correlation analysis of ppVD and pRNFL thickness in each quadrant of the NDR group showed a positive correlation between nasal and superior(all P<0.01),while inferior and temporal had no significant correlation(all P>0.05).There was no significant correlation between the HbA1c level and ppVD and pRNFL in any quadrant(all P>0.05).There was no significant correlation between the course of diabetes mellitus and ppVD and pRNFL in any quadrant(all P>0.05).CONCLUSION:ppVD and pRNFL decrease in eyes of children with type 1 diabetes before clinically detectable retinopathy and OCTA is helpful for early monitoring.

Corneal nerve changes by anti-glaucoma medications examined by in vivo confocal microscopy

AIM:To evaluate the effects of antiglaucoma eye drops on corneal nerves by in vivo confocal microscopy(IVCM).METHODS:This study comprised 79 patients diagnosed with glaucoma and 16 healthy control individuals.Among the glaucoma patients,54 were treated with medication,while 25 remained untreated.Central corneal images were evaluated by IVCM,and then ACCMetrics was used to calculate the following parameters:corneal nerve fiber density(CNFD),branch density(CNBD),fiber length(CNFL),total branch density(CTBD),fiber area(CNFA),fiber width(CNFW),and fractal dimension(CNFrD).The correlation between IVCM parameters and drugs was evaluated using non-parametric measurements of Spearman’s rank correlation coefficient.RESULTS:The CNFD was reduced in glaucoma groups compared to healthy subjects(P<0.01).Patients using anti-glaucoma medications exhibited poorer confocal parameters compared to untreated patients.As the number of medications and usage count increased,CNFD,CNBD,CNFL,CTBD,CNFA,and CNFrD experienced a decline,while CNFW increased(all P<0.01).For the brinzolamide-therapy group,there was a significant decrease in CNFD and CNFL compared to the other monotherapy groups(P<0.001).In the absence of medication,CNFD in males was lower than that in females(P<0.05).Among patients under medication therapy,CNFD remained consistent between males and females.CONCLUSION:Antiglaucoma eye drops affect the microstructure of corneal nerves.IVCM and ACCMetrics are useful tools that could be used to evaluate the corneal nerve changes.

Analysis of risk and protective factors associated with retinal nerve fiber layer defect in a Chinese adult population

AIM:To investigate the risk and protective factors associated with the retinal nerve fiber layer defect(RNFLD)in a Chinese adult population.METHODS:This study was a cross-sectional populationbased investigation including employees and retirees of a coal mining company in Kailuan City,Hebei Province.All the study participants underwent a comprehensive systemic and ophthalmic examination.RNFLD was diagnosed on fundus photographs.Binary logistic regression was used to investigate the risk and protective factors associated with the RNFLD.RESULTS:The community-based study included 14440 participants.There were 10473 participants in our study,including 7120 males(68.0%)and 3353 females(32.0%).The age range was 45-108y,averaging 59.56±8.66y.Totally 568 participants had RNFLD and the prevalence rate was 5.42%.A higher prevalence of RNFLD was associated with older age[P<0.001,odds ratio(OR):1.032;95%confidence interval(CI):1.018-1.046],longer axial length(P=0.010,OR:1.190;95%CI:1.042-1.359),hypertension(P=0.007,OR:0.639;95%CI:0.460-0.887),and diabetes mellitus(P=0.019,OR:0.684;95%CI:0.499-0.939).The protective factors of RNFLD were visual acuity(P=0.038,OR:0.617;95%CI:0.391-0.975),and central anterior chamber depth(P=0.046,OR:0.595;95%CI:0.358-0.990).CONCLUSION:In our cross-sectional community-based study,with an age range of 45-108y,RNFLD is associated with older age,longer axial length,hypertension,and diabetes mellitus.The protective factors of RNFLD are visual acuity and central anterior chamber depth.These can help to predict and evaluate RNFLD related diseases and identify high-risk populations early.

Quantitative study of peripapillary retinal nerve fiber layer thickness and peripapillary vessel density in patients with different stages of Parkinson's disease

AIM: To observe the changes in the thickness of peripapillary retinal nerve fiber layer(p RNFL) and peripapillary vessel density(pVD) in patients with different stages of Parkinson's disease(PD).METHODS: Totally 47 patients(47 eyes) with primary PD were divided into the mild group and the moderateto-severe group according to Hoehn & Yahr(H&Y) stage. Among them, there were 27 cases(27 eyes) in mild group and 20 cases(20 eyes) in moderate-to-severe group. And 20 cases(20 eyes) who were included in the control group were healthy people who came to our hospital for health screening at the same time. All participants underwent optical coherence tomography angiography(OCTA) examinations. The pRNFL thickness, total vessel density(tVD) and capillary vessel density(cVD) of the optic disc in average, superior half, inferior half, superior nasal(SN), nasal superior(NS), nasal inferior(NI), inferior nasal(IN), inferior temporal(IT), temporal inferior(TI), temporal superior(TS), and superior temporal(ST) were measured. One-way ANOVA was used to compare the differences of optic disc parameters among the three groups, and Pearson and Spearman correlations were used to analyze the correlation between pRNFL, pVD and the disease duration, H&Y stage and UPDRS-Ⅲ score in patients with PD, respectively.RESULTS: There were significant differences in p RNFL thickness in average, superior half, inferior half, SN, NS, IN, IT and ST quadrants among the three groups(P<0.05). In PD group, the pRNFL thickness in average, superior half, inferior half, NS and IT quadrants were negatively correlated with H&Y stage and UPDRS-Ⅲ score, respectively(P<0.05). There were statistically significant differences in the cVD of whole image, inferior half, NI and TS quadrants, the tVD of the whole image, inferior half, and peripapillary among the three groups(P<0.05). In PD group, the tVD of whole image and the c VD of NI and TS quadrants were negatively correlated with the H&Y stage, respectively(P<0.05);the cVD of TS quadrant was negatively correlated with UPDRS-Ⅲ score(P<0.05).CONCLUSION: The thickness of pRNFL in PD patients is significantly decreased, and it is negatively correlated with H&Y stage and UPDRS-Ⅲ score. With the increase of the severity of the disease, the pVD parameters in PD patients increase at first in the mild group, and then decrease in the moderate-to-severe group, and negatively correlate with H&Y stage and UPDRS-Ⅲ score.

Bilateral retinal nerve fiber layer thickness reduction in a 9-year-old myopic boy suffering from unilateral optic neuritis:A case report

BACKGROUND In this paper,we present a 9-year-old boy who demonstrates a complex interplay between myopia progression,axial length(AL)extension,and retinal nerve fiber layer(RNFL)thickness loss in both eyes.Additionally,concurrent optic neuritis has directly impacted RNFL thickness in his right eye,and its potential indirect influence on RNFL and macular ganglion cell layer(mGCL)thickness in his left eye is also noteworthy.CASE SUMMARY A 9-year-old boy with bilateral myopia presented with diminished vision and pain in his right eye due to optic neuritis,while his left eye showed pseudopapilledema.Steroid therapy improved his vision in the right eye,and 16-mo follow-up revealed recovery without recurrence despite myopia progression.Follow-up optical coherence tomography conducted 16 mo later revealed a notable thinning of the RNFL in both eyes,especially along with a reduction in mGCL thickness in the left eye.This intricate interaction between optic neuritis,myopia,and retinal changes underscores the need for comprehensive management,highlighting potential long-term visual implications in young patients.CONCLUSION The progression of myopia and AL extension led to the loss of RNFL thickness in both eyes in a 9-year-old boy.Concurrently,optic neuritis directly affected RNFL thickness in his right eye and may indirectly play a role in the thickness of RNFL and mGCL in his left eye.

Macular and peripapillary retinal nerve fiber layer thickness in children with hyperopic anisometropic amblyopia

AIM:To compare the retinal nerve fiber layer (RNFL) thickness and macular thickness in the amblyopic eye with that in the sound eye of children with hyperopic anisometropic amblyopia using optical coherence tomography (OCT). METHODS:A prospective, nonrandom, intraindividual comparative cohort study includes 72 children with hyperopic anisometropic amblyopia in a single center. Macular thickness, macular foveola thickness, and peripapillary RNFL thickness were compared between the amblyopia eyes and the contralateral sound eyes. ·RESULTS:There were 38 male and 34 female patients, with a mean age as 9.7 ±1.9 years (range, 5-16 years). Hyperopic was +3.62±1.16D (range +2.00D to +6.50D) in the amblyopic eyes, which was significantly higher in the control eyes with +0.76±0.90D (range 0D to +2.00D) (P 【 0.01). The mean peripapillary RNFL thickness was 113.9± 7.2μm and 109.2 ±6.9μm in the amblyopic eye and the normal eye, respectively, reaching statistical significance (P = 0.02). The mean macular foveola thickness was significantly thicker in the amblyopic eyes than the contralateral sound eyes (181.4±14.2μm vs 175.2±13.3μm, P 【0.01), but the 1mm, 3mm or 6mm macular thickness central macular thickness was not significantly different. Degree of anisometropia in the contralateral eyes was not significantly correlated with differences of peripapillary RNFL, macular foveola thickness or central macular thickness. CONCLUSION:Eyes with hyperopic anisometropic amblyopia are found thicker macular foveola and peripapillary RNFL than the contralateral eyes in children.

Evaluation of peripapillary retinal nerve fiber layer, macula and ganglion cell thickness in amblyopia using spectral optical coherence tomography

AIM:To investigate peripapillary retinal nerve fiber layer (RNFL), macula and ganglion cell layer thicknesses (GCC) in amblyopic eyes with spectral domain optical coherence tomography (SD-OCT). METHODS:Thirty six patients with a history of unilateral amblyopia and thirty two children who had emmetropia without amblyopia were included in this study. In this institutional study, 36 eyes of 36 patients with amblyopia (AE), 36 fellow eyes without amblyopia (FE), and 32 eyes of 32 normal subjects (NE) were included. RNFL, GCC and macular thickness measurements were performed with RS-3000 OCT Retina Scan (Nidek Inc CA. USA). RESULTS:The mean global thicknesses of the RNFL were 113.22 ±21.47, 111.57 ±18.25, 109.96 ±11.31μm in the AE, FE, and NE, respectively. There was no statistically significant difference for mean global RNFL thickness among the eyes (P =0.13). The mean thicknesses of the macula were 258.25±18.31, 258.75±19.54, 248.62±10.57μm in the AE, FE and NE, respectively. There was no statistically significant difference for thickness of macula among the eyes (P =0.06). The GCC was investigated into two parts:superior and inferior. The mean thicknesses of superior GCC were 102.57 ±13.32, 103.32 ±10.64, 100.52 ± 5.88μm in the AE, FE, and NE, respectively. The mean thicknesses of inferior GCC were 103.82 ±12.60, 107.82 ± 12.33, 105.86±10.79μm in the AE, FE and NE, respectively. There was no statistically significant difference for thickness of superior and inferior GCC between the eyes (P =0.63, P =0.46). ·CONCLUSION:The macular thicknesses of AE and FE were greater than the NE, although it was not statistically significant. Amblyopia does not seem to have a profound effect on the RNFL, macula and GCC.

Effect of suction on macular thickness and retinal nerve fiber layer thickness during LASIK used femtosecond laser and Moria M2 microkeratome

·AIM: To compare the effect of suction on the macular thickness and retinal nerve fiber layer(RNFL) thickness during laser in situ keratomileusis(LASIK) used Ziemer FEMTO LDV femtosecond laser(Ziemer group) and Moria M2 automated microkeratome(Moria group) for flap creation.· METHODS: Fourier-domain optical coherence tomography(FD-OCT) was used to measure macular thickness, ganglion cell complex thickness and RNFL thickness of 204 eyes of 102 patients with the Ziemer femtosecond laser(102 eyes) and the Moria M2microkeratome(102 eyes) before surgery and 30min; 1,3d; 1wk; 1, 3mo; 1y after surgery.· RESULTS: The average foveal thickness and parafoveal retinal thickness 30 min after the surgery were statistically more than that before surgery(Ziemer P 【0.001,P =0.003 and Moria P=0.001, P=0.006) and the effect was less in the Ziemer group than that in the Moria group(P all 【0.05). The ganglion cell complex thickness was not significantly changed in both groups(P all 】0.05). The RNFL thickness was statistically less 30 min after surgery in both groups(P=0.014, P 【0.001), but the influence was less in Ziemer group than that in Moria group(P =0.038).However, the RNFL thickness had recovered to the preoperative level only 1d after surgery.·CONCLUSION: The suction of femtosecond laser and mechanical microkeratome led to the increase in macular central fovea thickness and the decrease in RNFL thickness values at the early stage after LASIK. The effect of suction on macular and the RNFL thicknesses in Ziemer group is smaller than that in Moria group.

Remodeling of skin nerve fibers during burn wound healing

Burn wound healing involves a complex sequence of processes. Recent studies have revealed that skin reinnervation may have an impact on physiological wound repair. Few studies have addressed the process of reinnervation and morphological changes in regenerated nerve fibers. The regeneration of neurites during full-thickness burn wound healing was determined by immunofluorescent staining using an anti-neurofilament protein monoclonal antibody, and three-dimensional morphology was observed under a laser scanning confocal microscope. Morphology and the volume fraction of collagen and nerve fibers were measured. Skin reinnervation increased during wound healing, peaked during the proliferative scar stage, and then decreased to lower levels during the maturation period. The results from the skin nerve fibers correlated with those from collagen using semi-quantitative analysis. Disintegration and fragmentation were observed frequently in samples from the proliferative stage, and seldom occurred during the maturation stage. There was a remodeling process of regenerated nerve fibers during wound healing, which comprised changed innervation density and topical morphology. The mechanism of remodeling for nerve fibers requires further investigation.

Retinal nerve fiber layer thickness changes in obstructive sleep apnea syndrome: one year follow-up results

·AIM: To investigate the retinal nerve fiber layer(RNFL)thickness changes in patients with obstructive sleep apnea syndrome(OSAS) for one year follow-up. To discuss the possibility of detecting tendency of glaucoma in this population by using spectral domain optical coherence tomography(3D-OCT-2000 Spectral domain).·METHODS: After polysomnographic study, all subjects(64 OSAS patients and 40 controls) underwent detailed ophthalmological examination. After these examinations,patients with glaucoma and patients who had ophthalmological and/or systemic disease were excluded from the study.Totally, 20 patients in OSAS group and five patients in controls were excluded from the study in the first examination and follow-up period. The RNFL thickness was assessed with OCT. Forty-four OSAS patients and 35 control subjects were followed up for12 mo. RNFL thickness change and OSAS patients were evaluated for severity of disease by Apnea-Hypopnea Index(AHI).·RESULTS: Forty-four OSAS patients and 35 controls were enrolled in the study. Statistically significance was found between OSAS patients and controls at the 12 thmo.Average RNFL thickness was found to be significantly lower in last measurements in OSAS patients when compared with first measurements and control subjects(P 【0.001, 0.002, respectively). There was a statistically significant correlation among AHI, and RNFL thickness(P 【0.05).·CONCLUSION: The results suggest that the patients with OSAS were related with a proportional decrease in the RNFL thickness. These patients should be followed up regularly for glaucomatous changes. Detecting more RNFL thinning in severe OSAS was important.

Analysis of peripapillary retinal nerve fiber layer and inner macular layers by spectral-domain optical coherence tomography for detection of early glaucoma

AIM： To analyze the diagnostic capabilities of peripapillary retinal nerve fiber layer（p RNFL） thickness and segmented inner macular layer（IML） thickness measured by spectraldomain optical coherence tomography for detection of early glaucoma. METHODS： Fifty-three patients with primary open angle glaucoma（POAG）, 60 patients with normal tension glaucoma（NTG） and 32 normal control subjects were enrolled. Thicknesses of p RNFL, total macular layers（TML）, and the IML, including macular RNFL（m RNFL） and macular ganglion cell layer（m GCL） were assessed. The areas under the receiver operating characteristic curves（AROC） were calculated to compare the diagnostic power of different parameters. RESULTS： There were no differences in the parameters of p RNFL, TML, and IML between POAG and NTG groups. The thicknesses of superior and inferior m GCL showed significant correlation with mean deviation of visual field（R2=0.071, P=0.004; R2=0.08, P=0.002）. The m GCL thickness significantly correlated with the p RNFL thickness in the superior and inferior quadrants（R2=0.156, P〈0.001; R2=0.407, P〈0.001）. The thickness of the inferior-outer sector of macula had greater AROCs than those in the inferior-inner sector of macula. The AROCs for superior（0.894） and inferior（0.879） p RNFL thicknesses were similar with the AROCs for superior（0.839） and inferior m GCL（0.864） thicknesses. Sensitivities at 80% specificity for global p RNFL, inferior-outer m GCL and inferior-outer m RNFL thicknesses were 0.938, 0.867, and 0.725, respectively. CONCLUSION： The diagnostic capability of the m GCL thickness is comparable to that of the p RNFL thickness in patients with early glaucoma. The inferior-outer sector of IML has a better diagnostic capability than the inferiorinner sector of IML for detection of early glaucoma.

Diurnal changes in retinal nerve fiber layer thickness with obstructive sleep apnea/hypopnea syndrome

AIM： To compare the retinal nerve fiber layer （RNFL） thickness in the morning and evening in Thai patients with varying degrees of obstructive sleep apnea/ hypopnea syndrome （OSAHS）. METHODS： In this cross-sectional study, potential OSAHS patients at Siriraj Hospital underwent polysomnography to determine the severity of OSAHS and an eye examination （including best corrected visual acuity, slit-lamp examination, and Goldmann applanation tonometry）. RNFL thickness was recorded once in the morning and once in the evening, using spectral domain optical coherence tomography. Thickness was expressed as an average and given for each quadrant. Patients with ocular or systemic diseases that might affect RNFL thickness were excluded. RESULTS： Forty-one eyes of 41 patients were classified into 40SAHS groups. The average and mean RNFL thickness in most of the four quadrants of the severe OSAHS group trended toward being less than those in the comparable quadrants of the other groups in both the morning and evening. In the moderate OSAHS group, the average RNFL thickness and temporal and superior quadrant thickness in the morning were significantly higher than in the evening （P=0.01, P=0.01, and P=0.03, respectively）. In the severe OSAHS group, the inferior quadrant thickness in the morning was significantly higher than in the evening （P =0.03）. CONCLUSION： The RNFL thickness in the morning was higher than in the evening in moderate OSAHS.

Damage patterns of retinal nerve fiber layer in acute and chronic intraocular pressure elevation in primary angle closure glaucoma

AIMTo observe the differences of damage patterns of retinal nerve fiber layer (RNFL) between acute and chronic intraocular pressure (IOP) elevation in primary angle closure glaucoma (PACG) using optical coherence tomography (OCT).

Topographic distribution features of the choroidal and retinal nerve fiber layer thickness in Chinese school-aged children

AIM:To explore the topographic distribution features of choroidal thickness(CT)and retinal nerve fiber layer thickness(RNFLT),and determine the relationship between CT and ocular parameters in school-aged children.METHODS:The healthy school-aged children with low ametropia or emmetropia in Wenzhou were recruited for this cross-sectional study.With high-density optical coherence tomography(HD-OCT)combined with MATLAB software,the CT and RNFLT values in the macular area were measured at different locations and compared.Statistical analyses were performed to evaluate the correlation between CT and ophthalmic parameters,such as spherical equivalent(SE)and the axial length(AL).RESULTS:A total of 279 school-aged children with8.00±1.35 years of mean age(range,6-10 y)were included.The mean AL was 23.66±0.86 mm.The mean CT in CT-C(264.31±48.93μm)was thicker than that in CT-N1(249.54±50.52μm),and the average CT in the parafoveal region was also thicker than that in CT-N2(235.65±50.63μm).The subfoveal CT also varied substantially across refractive errors(P<0.001),and those with myopia(250.59±47.01μm)exhibited a thinner choroid compared with those with emmetropia(278.74±48.06μm).CT negatively correlated with AL(y=-21.72 x+779.17;R^2=0.1458),and positively correlated with SE(y=15.76 x+271.9;R^2=0.0727.OD;y=18.31 x+269.8;R^2=0.1007.OS).The average RNFLT was thickest in the peripapillary region(236.35±19.03μm),the mean RNFLT-S(131.10±15.16μm)was thicker than the RNFLT-I(128.20±16.59μm),and the mean RNFLT-T(76.54±11.99μm)was thicker than the RNFLT-N(64.28±8.55μm).The variations in the RNFLT between quadrants did differ between those with myopia and emmetropia(P<0.05).CONCLUSION:We establish demographic information for the choroid and RNFLT.These findings provide information that should be considered in future analyses of the CT and RNFLT in OCT studies in school-aged children.

Peripapillary retinal nerve fiber layer thickness distribution in Chinese with myopia measured by 3D-optical coherence tomography

AIMTo assess the effect of myopia on the thickness of retinal nerve fiber layer (RNFL) measured by 3D optical coherence tomography (3D-OCT) in a group of nonglaucomatous Chinese subjects.

Retinal vessel diameters and their correlation with retinal nerve fiber layer thickness in patients with pseudoexfoliation syndrome

AIM: To compare retinal artery-vein diameters(RAVDs)of patients with pseudoexfoliation(PSX) syndrome with healthy controls and investigate the correlations between retinal nerve fiber layer(RNFL) thickness parameters and RAVDs.METHODS: Seventeen eyes with PSX and 17 eyes of age-matched controls were included in the study. All participants underwent routine ophthalmological examination, Humphrey visual field and RNFL examination by using Stratus OCT. Retinal images were obtained by using a retinal camera(Topcon 501X).RAVDs were measured from inferior nasal, inferior temporal, superior nasal and superior temporal arcuates by using IMAGEnet software. Superior, inferior, nasal,temporal and average RNFL thicknesses were recorded.RAVDs and RNFL parameters in groups and correlations were analyzed by Mann-Whitney U and Spearmann correlation tests.RESULTS: Only inferior quadrant and average RNFL thickness were detected thinner in the PSX group compared with control group(P =0.009, P =0.038,respectively). No statistically significant difference regarding RAVDs was found between two groups.CONCLUSION: RAVDs seems to be comparable in the PSX and control group. RNFL is thinner in the inferior quadrant in the PSX group. RNFL thickness and RAVDs show significant correlations in both groups. This correlation doesn’t seem to be specific to PSX.

The correlation between rat retinal nerve fiber layer thickness around optic disc by using optical coherence tomography and histological measurements

·AIM: To explore the correlation between the retinal nerve fiber layer (RNFL) thickness by using optical coherence tomography (OCT) and by histological measurements in normal adult rats and optic nerve transected rats. · METHODS: The RNFL thickness of 36 rats was scanned in a circle 3.46mm far from the optic disc by OCT. The two experimental groups were the normal group ( =20 rats) and the optic nerve transected group ( =16 rats). The latter group included 4 groups ( =4 /group) surviving for 1 day, 3, 5 and 7 days. Then the RNFL thickness of the same retina area was also measured by NF -200 immunohistochemical staining method. Linear regression was used to analyze the correlation between the data obtained from these two methods. ·RESULTS: The RNFL thickness of normal right eyes around optic disc by OCT was 72.35 ±5.71μm and that of the left eyes was 72.65 ±5.88μm ( =0.074). The RNFL thickness of the corresponding histological section by immunohistochemistry was 37.54 ±4.05μm (right eyes) and 37.38 ±4.23μm (left eyes) ( =0.059). There was a good correlation between the RNFL thickness measured by OCT and that measured by histology (R 2 =0.8131). After optic nerve transection, the trend of the RNFL thickness was thinner with the prolonged survival time. The correlation of the thickness detected by the above two methods was approximately (R 2 =0.8265). Value of the RNFL thickness in rats around optic disc measured by OCT was obviously higher than that measured by common histological measurement in normal adult rats and optic nerve transected rats. ·CONCLUSION: The RNFL thickness measured by OCT has a strong correlation with that measured by histological method. Through OCT scanning, we found that the thickness of RNFL gradually becomes thinner in a time-dependent manner.

Reproducibility of peripapillary retinal nerve fiber layer thickness measurements with Cirrus HD-OCT in glaucomatous eyes

AIM: To assess the reproducibility of Cirrus high-definition optical coherence tomography(HD-OCT; Carl Zeiss Meditec, Dublin, CA, USA) for analysis of peripapillary retinal nerve fiber layer(RNFL) thickness in glaucomatous eyesMETHODS: Forty-five eyes(one eye from each glaucomatous patient) were imaged with Cirrus HD-OCT.Each eye was imaged three times by two separate operators. Intraclass correlation coefficient(ICC),coefficient of variation(CV), and test-retest variability were evaluated for both intraobserver and interobsever measurementsRESULTS: In intraobserver measurements, the average RNFL thickness ICC was 0.983. CV and test-retest variability were 2.3% and 4.4 μm respectively. In quadrants ICC ranged from 0.886 to 0.956, the lowest associated with nasal quadrant and CV ranged from 3.6%to 7.7%. In interobsever measurements, the average RNFL thickness ICC was 0.979. CV and test-retest variability were 2.4% and 4.5 μm respectively. In quadrants ICC ranged from 0.886 to 0.957, the lowest associated with nasal quadrant and CV ranged from 3.8%to 8.6%.CONCLUSION: The reproducibility of Cirrus OCT for RNFL thickness is sufficiently good to be useful clinically as a measure of glaucoma progression.