Localized Retinal Nerve Fiber Layer Research Articles

Genetic risk of glaucoma is associated with vascular and retinal nerve fibre wedge defects.

To evaluate the association between localised vascular and retinal nerve fibre layer (RNFL) loss and genetic risk for glaucoma and cardiovascular disease using polygenic risk scores (PRS). 858 eyes were included from 455 individuals with suspect and early manifest primary open angle glaucoma. Eyes were characterised as having localised vascular and/or RNFL wedge-shaped defects by scrutiny of optical coherence tomography angiography (OCTA) and OCT images, respectively. Investigations included associations with pre-established scores for genetic risk of glaucoma and cardiovascular disease in the context of glaucoma risk factors and systemic vascular disease outcomes. Higher genetic risk for glaucoma was associated with both vascular wedge defects and RNFL defects (p < 0.001 and p = 0.020, respectively). A greater genetic risk of glaucoma was associated with the presence of multiple vascular wedges per eye (p = 0.005). Glaucoma progression based on global RNFL loss was associated with vascular and RNFL wedge defects (p ≤ 0.001 and p = 0.008, respectively). The glaucoma PRS was significantly associated with vascular, but not RNFL, wedge defects after controlling for disc haemorrhage (p = 0.007 and p = 0.070, respectively). Vascular wedge defects were not related to the cardiovascular PRS. Individuals with a higher genetic risk of glaucoma based on the PRS were more likely to have retinal vascular defects, as well as structural glaucomatous loss, but this did not relate to systemic cardiovascular risk. This possibly implies a local pathophysiology for the vascular defects in some cases, which may have clinical relevance in the early stages of glaucoma and in individuals at high genetic risk.

Association between localized retinal nerve fiber layer defects in nonglaucomatous eyes and metabolic syndrome: a propensity score-matched analysis.

We investigated the association between metabolic syndrome and localized retinal nerve fiber layer (RNFL) defects in nonglaucomatous subjects. We examined 20,385 adults who visited the Health Promotion Center of Seoul St. Mary's Hospital between May 2015 and April 2016. After excluding those with known glaucoma or glaucomatous optic discs, subjects with and without localized RNFL defects were 1:5 propensity score matched. Metabolic syndrome components, including central obesity, elevated triglyceride, reduced high-density lipoprotein (HDL) cholesterol, elevated blood pressure (BP), and elevated fasting glucose, were compared between two groups. We performed logistic regression to investigate the association between RNFL defects and each component of metabolic syndrome and the number of metabolic syndrome components. Subjects with RNFL defects showed higher waist-to-hip ratios, systolic BP (SBP) and diastolic BP (DBP), fasting blood glucose, and hemoglobin A1c (HbA1c) levels than did those without RNFL defects both before and after propensity score matching. The number of metabolic syndrome components was significantly greater in those with RNFL defects (1.66±1.35) than in those without (1.27±1.32, P<0.01). In multivariate logistic regression, the odds ratio (OR) of RNFL defects was significantly increased in subjects with central obesity [OR =1.53, 95% confidence interval (CI): 1.11-2.13], elevated BP (OR =1.50, 95% CI: 1.09-2.05), and an elevated fasting glucose level (OR =1.42, 95% CI: 1.03-1.97). An increased number of metabolic syndrome components was associated with a higher risk of RNFL defects. Localized RNFL defects in nonglaucomatous subjects are associated with metabolic syndrome components, including central obesity, elevated BP, and an elevated fasting glucose level, suggesting that comorbid metabolic syndrome should be considered when evaluating subjects with RNFL defects.

Discrepancy between peripapillary retinal and choroidal microvasculature and the rate of localized retinal nerve fiber layer thinning in glaucoma

This observational case series study is conducted to compare the extent of microvasculature impairment in the peripapillary retina and choroid in eyes with primary open-angle glaucoma (POAG), and to investigate the association of the discrepancy between the microvasculature impairments of each layer with the rate of progressive retinal nerve fiber layer (RNFL) thinning. A total of 88 POAG eyes with a localized RNFL defect were enrolled, including 67 eyes with and 21 eyes without choroidal microvasculature dropout (CMvD). Circumferential widths of retinal microvascular impairment (RMvI) and CMvD were measured, and eyes were classified based on the relative width of CMvD to RMvI (CMvD/RMvI ratio). The rate of RNFL thinning was determined by linear regression based on ≥ 5 serial OCT examinations. Thinner global RNFL and worse visual field mean deviation at baseline were associated with a larger circumferential width of the RMvI, whereas the presence of cold extremities, lower mean arterial pressure and thinner juxtapapillary choroid were associated with a larger circumferential width of the CMvD. The rate of global RNFL thinning was faster in eyes with larger relative CMvD width than in eyes with equal CMvD and RMvI widths and in eyes without CMvD (P = 0.001). Lower mean arterial pressure (P = 0.041), larger CMvD width (P = 0.046), larger CMvD/RMvI ratio (P = 0.041), and detection of disc hemorrhage during the follow-up (P = 0.013) were significant factors associated with faster global RNFL thinning. Larger CMvD width relative to RMvI width may be indicative of an increased risk of faster RNFL thinning in POAG with localized RNFL defect. Comparing the microvasculature impairment in individual layers may help predict more rapid glaucoma progression.

Commentary: Rethinking 10-2 visual fields in early diagnosis of glaucoma for a glided glaucoma practice: The right choice to pick up a feeble noise?

Commentary: Rethinking 10-2 visual fields in early diagnosis of glaucoma for a glided glaucoma practice: The right choice to pick up a feeble noise?

Microvasculature Dropout and Development of Normal Tension Glaucoma in Glaucoma Suspects: The Normal Tension Glaucoma Suspect Cohort Study

To investigate the contribution of vessel parameters to identify normal tension glaucoma (NTG) suspects at risk of NTG development. Multicenter prospective cohort study. A total of 307 eyes of 307 NTG suspects having intraocular pressure within the normal range; a suspicious optic disc, but without definite localized retinal nerve fiber layer (RNFL) defects; and a normal visual field (VF). To measure laminar vessel density (VD), the VD was measured in the intradisc region from images of the deep vascular layers of optical coherence tomography angiography (OCT-A). Conversion to NTG was defined either by a new localized RNFL defect in the superotemporal or inferotemporal region, or the presence of a glaucomatous VF defect on 2 consecutive tests according to the pattern deviation plots. Conversion to NTG. In total, 73 (23.8%) of the 307 NTG suspects converted to NTG during the follow-up period of 59.84 ± 12.44 months. Detection rate of microvasculature dropout (MvD) was significantly higher in NTG suspects who progressed to NTG (50.7%) than in those who did not (6.4%; P < .001). The macular deep VD (P=.006) and laminar deep VD (P=.004) were significantly lower in NTG suspects who progressed to NTG. The presence of MvD (P < .001) and lower laminar deep VD (P=.006) were significantly associated with NTG conversion. NTG suspects with baseline MvD or a lower laminar deep VD on OCT-A had a higher risk of conversion.

Swept-source Optical Coherence Tomography Angiography in Active and Scarred Toxoplasmic Retinochoroiditis

ABSTRACT Purpose To describe optical coherence tomography angiography (OCTA) findings in eyes with active and scarred toxoplasmic retinochoroiditis. Methods OCTA scans in active (25 eyes) and scarred (17 eyes) retinochoroiditis were retrospectively reviewed. Results In active lesions, OCTA findings included a non-detectable flow signal area in retinal vascular plexuses and choriocapillaris in all 25 eyes (100%), an abnormal intraretinal vascular process in 2 eyes (8%), and an associated area of retinal flow deficit secondary to branch retinal artery occlusion in one eye (4%). In scarred lesions, OCTA findings included a flow deficit area in retinal vascular plexuses and choriocapillaris in all 17 eyes (100%), a visibility of larger deeper choroidal vessels at the level of choriocapillaris in 9 eyes (53%), and a well-defined intraretinal vascular network in one eye (5.9%). Peripapillary scars were associated on OCTA with wedge-shaped loss of radial peripapillary capillaries with corresponding localized retinal nerve fiber layer defect and visual field loss. Conclusion OCTA allows to non-invasively detect retinal and choroidal vascular changes in active and scarred toxoplasmic retinochoroiditis.

Understanding the role of microperimetry in glaucoma.

The present narrative review attempts to provide an overview on the use of microperimetry or fundus-driven perimetry in glaucoma, considering the clinical use, the different strategies and limits compared to standard automated perimetry. An electronic database (PubMed and Medline) search was performed of articles of any type published in the English language between 1998 and 2020 with a combination of the following terms: microperimetry, glaucoma, primary open-angle chronic glaucoma, visual field, Humphrey visual field, fundus automated perimetry. All the original articles, case reports, and short series analyzed were included in the present review, offering an excursus on the strengths and limitations characterizing the use of microperimetry in glaucomatous patients. The characteristics of a recently introduced fundus-driven perimetry Compass (CMP; Centervue, Padua, Italy) were also included. Although there remain several contradictions regarding routine use of microperimetry and the restricted research on this topic limits our ability to draw firm conclusions, microperimetry may be preferable in cases of localized retinal nerve fiber layer defects in patients with primary open-angle glaucoma and normal visual field. However, standard automated perimetry remains the gold standard for monitoring glaucoma, especially in patients with diffuse retinal nerve fiber layer impairment and visual field defects. The newly introduced Compass device can potentially provide a more accurate structural-functional evaluation than standard automated perimetry and can therefore produce superior testing reliability.

Predicting the development of normal tension glaucoma and related risk factors in normal tension glaucoma suspects

This study investigated the predicted risk factors for the development of normal-tension glaucoma (NTG) in NTG suspects. A total of 684 eyes of 379 NTG suspects who were followed-up for at least 5 years were included in the study. NTG suspects were those having (1) intraocular pressure within normal range, (2) suspicious optic disc (neuroretinal rim thinning) or enlarged cup-to-disc ratio (≥ 0.6), but without definite localized retinal nerve fiber layer (RNFL) defects on red-free disc/fundus photographs, and (3) normal visual field (VF). Demographic, systemic, and ocular characteristics were determined at the time of the first visit via detailed history-taking and examination of past medical records. Various ocular parameters were assess using spectral-domain optical coherence tomography and Heidelberg retinal tomography. Conversion to NTG was defined either by the presence of a new localized RNFL defect at the superotemporal or inferotemporal region on disc/fundus red-free photographs, or presence of a glaucomatous VF defect on pattern standard deviation plots on two consecutive tests. Hazard ratios were calculated with the Cox proportional hazard model. In total, 86 (12.6%) of the 684 NTG suspects converted to NTG during the follow-up period of 69.39 ± 7.77 months. Significant (P < 0.05, Cox regression) risk factors included medication for systemic hypertension, longer axial length, worse baseline VF parameters, thinner baseline peripapillary RNFL, greater disc torsion, and lamina cribrosa (LC) thickness < 180.5 μm (using a cut-off value obtained by regression analysis). Significant (P < 0.05, Cox regression) risk factors in the non-myopic NTG suspects included medication for systemic hypertension and a LC thinner than the cut-off value. Significant (P < 0.05, Cox regression) risk factors in the myopic NTG suspects included greater disc torsion. The results indicated that 12.6% of NTG suspects converted to NTG during the 5–6-year follow-up period. NTG suspects taking medication for systemic hypertension, disc torsion of the optic disc in the inferotemporal direction, and thinner LC of the optic nerve head at baseline were at greater risk of NTG conversion. Related baseline risk factors were different between myopic and non-myopic NTG suspects.

Determinants of vessel defects in superficial and deep vascular layers in normal-tension glaucoma using optical coherence tomography angiography

We investigated the characteristics of localized vessel density defects (VD) either in the deep or superficial vascular layer of normal-tension glaucoma patients using optical coherence tomography angiography (OCTA). In this retrospective, cross-sectional study, 74 eyes with localized retinal nerve fiber layer (RNFL) defect were included. The relationships between the widths of the VD in the superficial and deep layer and ocular factors were evaluated. Eyes with greater deep VD were significantly older (P = 0.023). The IOP measured at OCTA exam was significantly related to the width of the deep VD (P = 0.009). By contrast, average ganglion cell inner plexiform layer thickness (GCIPLT) was substantially related to the width of the superficial VD (P = 0.004). In logistic regression analysis, aging was noticeably associated with wider deep VD, whereas worse mean deviation (MD) had a significant association with wider superficial VD (P = 0.001, P = 0.003, respectively). In sum, while changes of the superficial layer seemed an overall ramification of glaucomatous damages, the deep layer was more likely to be affected by factors related to ocular microcirculation, such as IOPs and older age. Thus, looking into the deep vascular layer using OCTA could identify risk factors related to the disturbance in ocular microcirculation.

Ten-year-and-beyond longitudinal change of ß-zone parapapillary atrophy in glaucoma: association with retinal nerve fibre layer defect

BackgroundTo investigate the longitudinal change of localised retinal nerve fibre layer (RNFL) defects associated with change of ß-zone parapapillary atrophy (PPA) in primary open-angle glaucoma (POAG) eyes.MethodsPOAG patients with a...

The severity of visual field defect and the defective angles of localized retinal nerve fiber layer using a novel approach

A modified novel analytical method for evaluating photographic retinal nerve fiber layer defect (RNFLD) was developed for the purpose of estimating the severity of early glaucomatous eyes. This new method was then compared with the original method, as described below, in relation to the visual field defect severity. The clinical records of 47 glaucomatous eyes with qualified photographs were obtained from a prior retrospective study. The reference point of the angle was set at the center of the optic disc center (COD group) and the central vessel trunk (COV group). Angle α was the angular width between the fovea and the proximity of RNFLD, while angle β (+c) was the sum of the angular width(s) of localized RNFLD. The correlation between the visual field parameters and the angles of RNFLD in the above two groups were analyzed. There were significant differences in angle α (p=0.001) and angle β (+c) (p=0.016) between the two groups. Angle β (+c) showed significant correlation with MD (p=0.012), PSD (p=0.035), VFI (p=0.042) and MD (p=0.016), PSD (p=0.035), VFI (p=0.031) in the COD and COV group, respectively. No correlation was found between angle α and the presence of central scotoma in both groups. Our novel method was more convenient in a clinical setting and noninferior to the original method.

Optic disc morphology in primary open-angle glaucoma versus primary angle-closure glaucoma in South India.

Purpose:The aim of this study was to investigate the optic disc morphology in primary angle-closure glaucoma (PACG) versus primary open-angle glaucoma (POAG) in South Indians.Methods:A total of 60 patients (60 eyes) with PACG and 52 patients (52 eyes) with POAG were included in a cross-sectional observational study. The glaucoma diagnosis was based on a glaucomatous appearance of the optic disc correlating with visual field defects. The glaucoma was graded as early, moderate, or severe, depending upon perimetric loss. All patients underwent an ophthalmic evaluation, including visual field examination and planimetric analysis of 30° stereoscopic color optic disc photographs.Results:The POAG and PACG groups did not differ significantly in a disc or rim area, rim width, and frequencies of disc hemorrhages or rim notches. However, early POAG group (n = 15) had a significantly deeper cup depth (P = 0.01), larger beta zone (P = 0.01), and a higher frequency of localized retinal nerve fiber layer (RNFL) defects (P = 0.02) than early PACG (n = 20).Conclusion:In the early stage of the disease, POAG compared to PACG may be characterized by deeper disc cupping, a larger beta zone of peripapillary atrophy, and a higher frequency of localized RNFL defects. Such differences in early glaucoma may suggest differences in pathophysiology in POAG and PACG.

Relationship between Retinal Nerve Fiber Layer Defects and Coronary Artery Calcium Score in Patients at Risk for Cardiovascular Disease

Background: Noninvasive fundus imaging may provide useful information on blood vessels. This study investigated the relationship between localized retinal nerve fiber layer defects (RNFLDs) and vascular biomarkers.Methods: This study included 1,316 participants without cardiovascular disease who were registered in a cardiovascular high-risk cohort. Examined vascular biomarkers included central hemodynamics, carotid-femoral pulse wave velocity (cfPWV), left ventricular hypertrophy (LVH) on electrocardiogram, and coronary artery calcium score (CACS). Fundus photography and optical coherence tomography were used to evaluate RNFLDs. The associations between RNFLDs and established high-risk cutoff points for each biomarker (central blood pressure [BP] ≥125/80 mmHg, central pulse pressure [PP] ≥50 mmHg, cfPWV ≥10 m/s, presence of LVH, and CACS ≥300) were assessed.Results: RNFLD was identified in 394 participants (29.9%) who had higher fasting glucose level, lower renal function, and higher BP than those without RNFLDs. Additionally, central BP, central PP, cfPWV, CACS, and the percentage of subjects with LVH were higher in the RNFLD group. After adjusting for confounders, RNFLDs were not associated with LVH or an elevated central BP, central PP, or cfPWV. However, they were associated with an elevated CACS (odds ratio, 1.44; 95% confidence interval, 1.04–2.00; p=0.029).Conclusions: Non-glaucomatous localized RNFLDs were associated with elevated CACS. Therefore, evaluating RNFLDs using fundus imaging may aid in the assessment of cardiovascular disease risk.

Defective angles of localized retinal nerve fiber layer reflect the severity of visual field defect- a cross-sectional analysis

BackgroundIn order to detect glaucomatous optic nerve damages early on and evaluate the severity of glaucoma, a previously developed analytic method based on photographic retinal nerve fiber layer (RNFL) angle defect was proposed. However, the correlation between these defective angles and the severity of visual field defect has not been verified. This study aimed to confirm the correlation described above.MethodsWe reviewed a total of 227 glaucomatous eyes (38 enrolled, 189 excluded) during an interval of 5 years. The angles of all eyes were measured on RNFL photograph, of which angle α is the angular width between the macula center and the proximity of RNFL defect, and angle β (+c) is the sum of angular width(s) of localized RNFL defect. The severity of visual field defect was determined by mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI). Correlation analysis was performed on angle α and angle β (+c) with the presence of central scotoma and visual field defect parameters, respectively.ResultsAngle β (+c) showed significant correlation with MD (P = 0.007), PSD (P = 0.02), VFI (P = 0.03), and average RNFL thickness (P = 0.03). No correlation was found between angle α and the presence of central scotoma.ConclusionsIn conclusion, measuring the angular width of localized RNFL defect is a viable method for determining the severity of visual field defect.

Association between localised retinal nerve fibre layer defects and cardiovascular risk factors

Localised retinal nerve fibre layer defects (RNFLDs) are reported to indicate the degree of glaucomatous damage but can also be sequelae of retinal vascular insufficiency as a result of systemic vascular factors. We investigated the association between RNFLDs and cardiovascular risk factors. RNFLDs were detected in 440 (29.2%) of 1508 subjects. The presence of RNFLDs was associated with higher HbA1c (odds ratio [OR] 1.289, p < 0.001), higher 24-h mean systolic blood pressure (SBP; OR 1.013, p < 0.005), and lower estimated glomerular filtration rate (eGFR; OR 0.995, p < 0.005). An increasing number of RNFLDs was correlated with higher SBP (r = 0.186, p < 0.001), higher HbA1c (r = 0.128, p < 0.010), lower eGFR (r = −0.112, p < 0.020), and younger age (r = −0.303, p < 0.001). Subjects with RNFLDs had a higher predicted 10-year risk of atherosclerotic cardiovascular disease than did those without RNFLDs (9.7% vs 7.9%, p = 0.008 in middle-aged subjects, 25.6% vs 23.2%, p = 0.040 in older subjects). In conclusion, RNFLDs are associated with SBP, eGFR, and HbA1c. Concomitant cardiovascular risk factors should be considered when evaluating patients with localised RNFLDs.

Association between Chagas disease and changes in the optic nerve and retinal nerve fiber layer.

To test the hypothesis that Chagas disease predisposes to optic nerve and retinal nerve fiber layer alterations. We conducted a cross-sectional study including 41 patients diagnosed with Chagas disease and 41 controls, paired by sex and age. The patients underwent ophthalmologic examinations, including intraocular pressure measurements, optic nerve and retinal nerve fiber layer screening with retinography, optical coherence tomography, and standard automated perimetry. All of the patients with Chagas disease had a recent cardiologic study; 15 (36.6%) had heart failure, 14 (34.1%) had cardiac form without left ventricular dysfunction, and 12 (29.3%) had indeterminate form. Optic nerve/retinal nerve fiber layer alterations were observed in 24 patients (58.5%) in the Chagas disease group and 7 controls (17.1%) (p£0.01). Among these, optic nerve pallor, optic nerve alterations suggestive of glaucoma, notch, peripapillary hemorrhage, and localized retinal nerve fiber layer defect were detected. Alterations were more prominent in patients with Chagas disease and heart failure (11 patients), although they also occurred in those with Chagas disease without left ventricular dysfunction (7 patients) and those with indeterminate form (6 patients). Optical coherence tomography showed that themean of the average retinal nerve fiber layer thickness measured 89 ± 9.7 mm, and the mean of retinal nerve fiber layer superior and inferior thickness measured 109 ± 17.5 and 113 ± 16.8 mm, respectively were lower in patients with Chagas disease. In controls, these values were 94 ± 10.6 (p=0.02); 117 ± 18.1 (p=0.04), and 122 ± 18.4 mm (p=0.03). Changes in optic nerve/ retinal nerve fiber layer were more prevalent in patients with Chagas disease.

Visual Field Tests for Glaucoma Patients With Initial Macular Damage: Comparison Between Frequency-doubling Technology and Standard Automated Perimetry Using 24-2 or 10-2 Visual Fields

The purpose of this study was to compare standard automated perimetry (SAP) and frequency-doubling technology (FDT) perimetry for detecting macular damage in glaucoma. A total of 112 glaucomatous eyes with localized retinal nerve fiber layer defects on red-free photographs and corresponding macular ganglion cell/inner plexiform layer (mGC/IPL) thinning on the deviation map of macular optical coherence tomography, and 35 healthy eyes were enrolled in the study. All participants underwent SAP 24-2, SAP 10-2, FDT 24-2, and FDT 10-2 visual field (VF) tests. Significantly depressed points, with confidence limits of 5% and 1%, were checked for in the pattern deviation plots of the VF tests. Detection rate of the macular damage, sensitivity, and specificity were compared among various VF tests. Patients were divided into eyes with mGC/IPL thinning within the normative database, depressed <5% or <1%. Comparison of VF parameters between various VF tests were performed according to the degree of mGC/IPL thinning. All of the macular damage in glaucoma were detected using FDT 10-2 and 83.3% to 90.0% were detected using FDT 24-2 when the mGC/IPL thickness was <5%. Even when mGC/IPL thickness was within normal range, the detection rate of macular damage were 96% for FDT 10-2 and 80% for FDT 24-2. FDT 10-2 had the best diagnostic ability (areas under the receiver operating characteristics curve, 0.96) followed by FDT 24-2 (areas under the receiver operating characteristics curve, 0.76) for discriminating normal controls from glaucoma patients with macular damage. Comparing 10-2 and 24-2 tests with same strategy showed that FDT 10-2 was more sensitive than FDT 24-2 (P=0.004), with better specificity (P=0.010). Also, SAP 24-2 had similar specificity with SAP 10-2 (P=0.373), which was better than FDT 24-2 (P=0.016). The mean deviation of SAP 10-2 and the pattern standard deviation of SAP 10-2 were significantly related to mGC/IPL thickness. We found the detection rate of functional depression related to early macular damage were significant using FDT and parameters of SAP significantly predicted the degree of mGC/IPL thinning in glaucoma patients.

Comparison of changes of macular ganglion cell-inner plexiform layer defect between stable group and progression group in primary open-angle glaucoma.

To compare the changes in macular ganglion cell-inner plexiform layer (GCIPL) defect between stable and progression primary open-angle glaucoma (POAG) groups. Retrospective observational study. A total of 100 POAG eyes with localized retinal nerve fiber layer (RNFL) defect and corresponding macular GCIPL defect were selected for this study. Glaucoma progression was defined by either structural or functional deterioration. The number of abnormal superpixels on macular GCIPL deviation maps was calculated using a customized MATLAB program. GCIPL defect change was evaluated in two aspects: increased angular width and increased area. The defect patterns were categorized and compared between the stable and progression groups. The increase rate of angular width of GCIPL defect was higher in the progression group than in the stable group (P = 0.029). In respect to the area of GCIPL defect, there was no statistically significant differences between the groups (P = 0.227). Twenty-seven (27) of 100 (27.0%) eyes showed increased angular width of GCIPL defect. It was more frequent in the progression group than in the stable group (P = 0.043). Seventeen (17) of 27 (63.0%) eyes showed the away from the horizontal temporal raphe type progression and it was the most common change pattern of angular width of GCIPL defect. Increased angular width of GCIPL defect was the more prominent feature of change, and was more frequent in the progression group than in the stable group. Among the types of GCIPL defect classified, the away from the horizontal temporal raphe type was the most common.

Multicolor imaging for retinal nerve fiber layer defect in glaucoma

Glaucoma is a progressive optic neuropathy associated with irreversible loss of retinal ganglion cells (RGC). This emblematic localized retinal nerve fiber layer defect (RNFLD) can be the earliest sign to detect the ongoing glaucomatous damage. Slitlamp biomicroscopy [90D & 78D], colour and redfree fundus photography, OCT & HRT are used conventionally for early detection of RNFLD. Multicolour Imaging (MCI) is a new non-invasive retinal imaging modality available in Spectralis platform which simultaneously acquires three reflectance images of the retina using three individual lasers producing a composite image thereby allowing analysis of changes at various levels within the retina. MCI provides sharper image, enables imaging through small pupil and hazy media. Current report describes 2 cases where in MCI proved superior to CFP and conventional redfree photograph in delineating area of RNFLD. This is the first report of MCI in RNFL imaging. The present report highlights the role of MCI in detection of RNFLD.

Rates of Local Retinal Nerve Fiber Layer Thinning before and after Disc Hemorrhage in Glaucoma

To investigate longitudinal temporal and spatial associations between disc hemorrhage (DH) and rates of local retinal nerve fiber layer (RNFL) thinning before and after DHs. Longitudinal, observational cohort study. Forty eyes of 37 participants (23 with glaucoma and 17 with suspect glaucoma at baseline) with DH episodes during follow-up from the Diagnostic Innovations in Glaucoma Study and the African Descent and Glaucoma Evaluation Study. All subjects underwent optic disc photography annually and spectral-domain optical coherence tomography (OCT) RNFL thickness measurements every 6 months. The rates of RNFL thinning were calculated using multivariate linear mixed-effects models before and after DH. Rates of global and local RNFL thinning. Thirty-six eyes of 33 participants with inferior or superior DHs were analyzed. The rates of RNFL thinning were significantly faster in DH quadrants than in non-DH quadrants after DH (-2.25 and-0.69 μm/year; P < 0.001). In the 18 eyes with intensified treatment after DH, the mean rate of RNFL thinning significantly slowed after treatment compared with before treatment in the non-DH quadrants (-2.89 and-0.31 μm/year; P < 0.001), but not in the DH quadrants (-2.64 and-2.12 μm/year; P= 0.19). In 18 eyes with unchanged treatment, the rate of RNFL thinning in the DH quadrant was faster after DH than before DH (P= 0.008). Moreover, compared with eyes without a treatment change, intensification of glaucoma treatment after DH significantly reduced the global, non-DH quadrants, and DH quadrant rates of RNFL thinning after DH compared with before DH (global, P= 0.004; non-DH quadrant, P < 0.001; DH quadrant, P= 0.005). In the multiple linear regression analysis, treatment intensification (β, 1.007; P= 0.005), visual field mean deviation (β, 0.066; P= 0.049), and difference in intraocular pressure before and after DH (β,-0.176; P= 0.034) were associated significantly with the difference of global RNFL slope values before and after DH. Although the rate of RNFL thinning worsened in a DH quadrant after DH, glaucoma treatment intensification may have a beneficial effect in reducing this rate of thinning.