Retinal Nerve Fiber Layer Analysis Research Articles

Event-based analysis of visual field change can miss fast glaucoma progression detected by a combined structure and function index.

To investigate the relationship between progression assessed by the visual field guided progression analysis (GPA) and rates of structural and functional change in glaucoma eyes. This was a longitudinal observational study of 135 eyes of 97 patients with glaucoma followed for an average of 3.5 ± 0.9years. All patients had standard automated perimetry (SAP) and retinal nerve fiber layer (RNFL) analysis with spectral domain optical coherence tomography (SDOCT), with an average of 6.8 ± 2.3 visits. A control group of healthy eyes followed longitudinally was used to estimate age-related change. Visual field progression was assessed using the Humphrey Field Analyzer GPA. Estimates of retinal ganglion cell counts from SAP and SDOCT were used to obtain a combined index of glaucomatous damage (RGC index) according to a previously described algorithm. Progression by SDOCT and the retinal ganglion cell (RGC) index were defined as statistically significant (P < 0.05) slopes of change that were also faster than age-related change estimated from healthy eyes. From the 135 eyes, 15 (11%) progressed by GPA, 21 (16%) progressed by SDOCT, and 31 (23%) progressed by the RGC index. Twenty-one eyes showed progression by the RGC index that was missed by the GPA. These eyes had an average rate of change in estimated RGC counts of - 28,910 cells/year, ranging from two to nine times faster than expected age-related losses. Many glaucomatous eyes that are not found to be progressing by GPA may actually have fast rates of change as detected by a combined index of structure and function.

Retinal nerve fiber layer analysis in obstructive sleep apnea

Amac: Obstruktif uyku apne sendromu (OUAS) hastalarini retina sinir lifi tabakasi (RSLT) kalinliklari yonunden incelemek ve okuler degisikliklerin hastaligin siddeti ile iliskisini belirlemek. Gerec ve Yontem: OUAS tanili 54 hasta goz bulgulari acisindan degerlendirildi. Respiratory Disturbance Index-Anormal Solunum Olayi Indeksi (RDI) 5-29 olan 21’i grup 1, RDI>29 olan 33’ u ise grup 2 kapsaminda siniflandirildi. Hastalara Optik Koherens Tomografi (OKT) ile RSLT olcumleri yapildi. Gruplar elde edilen veriler acisindan karsilastirilirken, verilerin RDI, ortalama ve minimum O 2 saturasyonu ile olan iliskileri de incelendi. Bulgular: Ortalama RSLT grup 1’de 117,33±7,57 μm, grup 2’de ise 111,91 ±8,64 μm olarak olculdu. RSLT’deki incelme istatistiksel olarak anlamli bulundu (p=0,023). Inferior RSLT grup 1’de 147,95 ±12,97 μm, grup 2’de 137,27±17,94 μm olarak bulundu. Grup 2’deki incelme istatistiksel olarak anlamli bulundu (p=0,032). Ortalama RSLT ile RDI arasinda negatif korelasyon saptandi . Sonuc: OUAS hastalarinda RSLT kalinliginda azalma meydana gelmekte ve bu degisimler OUAS’in agirligi ile korelasyon gostermektedir. Bu iki durum arasindaki iliskinin bilinmesi hastalarin oncelikle goz hekimi tarafindan gorulduklerinde olasi OUAS semptomlari yonunden sorgulanmalarina olanak saglayacaktir.

Visual pathway function and structure in Wolfram syndrome: patient age, variation and progression

Background/aimsTo report alterations in visual acuity and visual pathway structure over an interval of 1–3 years in a cohort of children, adolescents and young adults who have Wolfram syndrome (WFS)...

Utility of Bruch membrane opening-based optic nerve head parameters in myopic subjects.

To evaluate whether the new rim analysis software with spectral-domain optical coherence tomography (SD-OCT) shows advantages over the retinal nerve fiber layer (RNFL) thickness in patients with moderate myopia. In this prospective cross-sectional study, we studied 65 healthy subjects, 37 with spherical refractive errors in the range of -3 to -6 D (moderate, G1) and 28 with less than -3 D (low/non-myopic, G0). All patients were examined with Heidelberg Spectralis SD-OCT, including Glaucoma Premium Module Edition (GPME) software. With GPME, we analyzed the neuroretinal rim (Bruch membrane opening-minimum rim width [BMO-MRW]) and RNFL. The average age of subjects was 30.2 ± 9.3 years for G0 and 29.9 ± 7.1 years for G1 (p = 0.903). Mean sphere was -0.5 ± 0.3 D (-1.25 to 0 D) G0 and -3.9 ± 0.3 D (-6.00 to -3 D) G1 (p<0.001). The RNFL thickness comparison between G0 and G1 showed a significantly lower thickness in G1 (p = 0.018). The BMO-MRW measurements were similar in both groups (p = 0.331). With the BMO-MRW examination, the number of sectors classified as pathologic per subject in G1 were significantly lower compared to RNFL analysis (p = 0.023). Ring analysis based on BMO-MRW measurements shows a lower rate of false-positives compared to RNFL thickness when studying healthy moderate myopic eyes and it would be advisable to take this into consideration when analyzing these patients.

The use of optical coherence tomography in neuro-ophthalmology

In the last decade, with the advances of optical coherence tomography (OCT) technology, different imaging protocols and analysis algorithms have been introduced to maximize the potential of this diagnostic tool in the evaluation of different eye diseases. This review aims to provide an update on these additional features, with respect to the management of a diverse range of neuro-ophthalmologic conditions. Macular ganglion cell complex (mGCC) analysis has been shown to be superior to peripapillary retinal nerve fiber layer (pRNFL) analysis in certain settings, such as differentiating Leber's hereditary optic neuropathy from functional visual loss; monitoring neurodegenerative diseases or multiple sclerosis; and predicting visual loss in nonarteritic ischemic optic neuropathy. mGCC analysis also demonstrates high correlation with perimetry and might serve as an early structural indicator of irreversible neuronal loss. Compared to pRNFL, retinal thickness analysis of the optic nerve head demonstrates better correlation with the severity of papilledema, thus enabling its possible application in detecting raised intracranial pressure, especially in the pediatric group. Upcoming research on emerging OCT technologies including OCT-angiography, enhanced depth imaging, retinal single-layer analysis and portable systems will hopefully further enhance the utility of OCT in the field. It is crucial for neuro-ophthalmologists to be updated and familiar with these newer OCT imaging protocols and to make appropriate choices for different clinical scenarios, in order to optimize the diagnostic sensitivity and specificity.

Relation between cardiovascular conditions and macular and retinal nerve fiber layer thickness evaluated with Spectral‐Domain OCT

PurposeTo detect changes in the macular and Retinal Nerve fiber Layer (RNFL) thickness in subjects with cardiovascular risk factors or subclinical ischemiaMethods152 healthy men were evaluated. They underwent cardiovascular examination (including quantification of classic major risk factors, blood analysis and quantification of subclinical atheroma plaques by ultrasound scans) and a complete ophthalmic evaluation including evaluation with spectral‐domain optical coherence tomography (SD‐OCT) registering macular and RNFL thicknessResultsSubjects without cardiovascular risk factors did not show higher macular or RNFL thicknesses than subjects with at least one risk factor. Subjects with subclinical atheroma plaques in the carotid artery showed significantly lower central macular thickness in the left eye compared to the right eye (p = 0.016). Subjects with atheroma plaques showed significantly reduced RNFL thickness in the superior quadrant (p = 0.044) and in the 2 o'clock sector (p = 0.014) compared to subjects without atheroma plaques. Smokers showed significant thinning in central macular thickness (p = 0.034), and also in the nasal RNFL quadrant (p = 0.006) and the 3 and 5 o'clock RNFL sectors (p = 0.016 and 0.009), compared to non‐smokersConclusionsSubjects with subclinical atherosclerosis assessed by ultrasound scans showed reduced RNFL thickness in the superior quadrant. Smokers showed reduced central macular thickness and reduced RNFL thickness in the nasal quadrant. Macular and RNFL analysis with SD‐OCT could be a good biomarker of early axonal damage in subjects with cardiovascular conditions

Interest of analysis of circumpapillary retinal nerve fibers layer thickness at different measurement diameters

PurposeThe analysis of the circumpapillary retinal nerve fiber layer (RNFL) is a major data in structural analysis in glaucoma. Since OCT development, analysis is on a circle of 3.4 mm diameter. This study evaluates the diagnostic capability of an RNFL analysis with different diameter measurements.Methods60 glaucomatous and 58 control patients had a complete ophthalmological exam to exclude patients with papillary morphological abnormalities (coloboma, dysversion …). Others had an OCT Spectralis (Heidelberg Engineering, Germany) of RNFL on 4 circles of different diameters: 3.4, 3.5, 4.1 and 4.7 mm. Only one eye per patient was randomly included. The diagnostic capabability of each of these circles was analyzed for global mean thickness and for each sector (temporal, temporal‐superior, nasal‐superior, nasal, nasal‐inferior and temporal‐inferior) by calculating areas under ROC curve (AUROC).ResultsPatients were comparable for clinical characteristics. In glaucomatous patient group, 58.9% of the patients were early glaucoma (MD&gt; ‐6 dB) and 21.4% of the patients were severe (MD &lt;‐12 dB). For conventional RNFL measurement (3.4 mm), the temporal‐inferior sector had the highest diagnostic capability with an AUROC of 0.916. For the 3.5 mm measurement, the global mean thickness of the RNFL had the highest diagnostic capability (AUROC = 0.909). For the 4.1 mm measurement, the global mean thickness of the RNFL had the highest diagnostic capability (AUROC = 0.915). For the 4.7 mm measurement, the average thickness of the temporal‐inferior sector had the highest diagnostic capability (AUROC = 0.909). There was no statistically significant difference between these 4 AUROC.ConclusionsRegardless of the diameter of RNFL analysis, the diagnostic capability remains very good with no significant difference in patients with normal papillary morphology.

Intraocular Pressure and Retinal Nerve Fibre Layer Thickness Changes After Carotid Artery Stenting.

Objectives:The aim of this study was to evaluate intraocular pressure (IOP) and retinal nerve fiber layer (RNFL) changes in patients with carotid artery stenosis (CAS) after carotid artery stenting.Materials and Methods:This study was conducted as a cross-sectional, non-randomised clinical case series. Fifteen male patients (mean age: 63.6±9.1) with CAS and more than 70% carotid artery narrowing were included. All of the patients were followed in the department of neurology and were operated in the interventional radiology division. Eighteen healthy male subjects (mean age: 63.7±5.3) were included in the control group. All of the healthy subjects had a detailed ophthalmological examination and subjects with any chronic eye disease were excluded from the study. All of the participants had a detailed ophthalmological examination including tonometry using Goldmann applanation tonometry and RNFL analysis using optical coherence tomography (RTVue-100 5.1).Results:There were no ocular ischemic symptoms in any of the participants. The mean IOP value was 15.1±2.1 mmHg in the control group and 16.6±2.4 mmHg before stent implantation, 16.4±2.2 mmHg at 1 week after implantation, 16.6±2.5 mmHg at 1 month after implantation, and 16.7±2.9 mmHg at 3 months after implantation in the CAS group. Mean RNFL thickness was 105±6 µm in the control group; in the CAS group, mean RNFL thickness values were 98±27 µm before stent implantation and 103±11 µm, 101±10 µm, and 101±11 µm at 1 week, 1 month, and 3 months after stenting. There were no significant differences between the CAS group and control group regarding IOP and RNFL thickness values (p>0.05). IOP and RNFL thickness also did not show any statistically significant changes from preoperative measurements in 3 months postoperative follow-up in the CAS group (p>0.05).Conclusion:IOP and RNFL thickness remained unchanged after carotid stent implantation in carotid artery stenosis patients with no signs of ocular ischemic syndrome.

Inter-visit Test-Retest Variability of OCT in Glaucoma.

To determine the inter-visit test-retest variability (TRV) of a spectral domain optical coherence tomograph, the Topcon 3D OCT-2000, in the measurement of optic nerve head topography, peripapillary retinal nerve fiber layer (pRNFL), and macular ganglion cell complex (GCC) parameters in glaucoma patients. We also examine whether TRV with this instrument varies with the extent of glaucomatous damage. Twenty-four subjects with varying degrees of glaucoma severity provided 41 eyes with usable results for the study. 3D Disc Retinal Nerve Fiber Layer Analysis and Macula V (GCC) scans were repeated 1 week apart, at the same time of day, to determine the inter-visit TRV. TRV was determined using Bland-Altman limits of agreement (LoA) and the resulting coefficients of repeatability (CR). The overall horizontal and vertical cup/disc ratio CRs were 0.05 and 0.07, respectively. The GCC CR was 2.9 μm. In contrast, average pRNFL TRV expanded with increasing damage, with the LoA being well fitted by ±(34.67 - 0.294(d)), where d is the pRNFL thickness. A more complex model, with constant LoA of ±5.61 μm at d >82 μm, and linearly expanding TRV below that, achieved marginal significance (P < .06). The repeatability of GCC measurements with this instrument was excellent. The determination of statistically significant change in average pRNFL should take into account average pRNFL thickness.

Resident Compliance With the American Academy of Ophthalmology Preferred Practice Patterns for Primary Open-Angle Glaucoma Suspect.

To study resident compliance with the American Academy of Ophthalmology (AAO) Preferred Practice Patterns (PPPs) for primary open-angle glaucoma suspect (POAGS) in a resident ophthalmology clinic. Two hundred charts were selected for analysis of adult patients with the International Classification of Diseases diagnosis code for POAGS during their initial visit between November 2, 2010 and May 6, 2014 at the Kresge Eye Institute resident clinic. Electronic medical records of clinic visits for POAGS patients were evaluated for documentation and compliance with 17 elements of AAO PPPs. The overall mean compliance was 73.8% for all charts (n=200), 74.4% for first-year residents (n=53), 74.5% for second-year residents (n=38), and 73.3% for third-year residents (n=109). Documentation rates were high (>90%) for 9 elements, which included most elements of physical examination and history. Documentation of ocular history, central corneal thickness, gonioscopy, optic nerve head and retinal nerve fiber layer analysis, and visual field ranged from 40% to 80%. Documentation was lowest for patient education elements which ranged from 0% to 10%. Compliance was not significantly different (P>0.05) between residents or between different resident years for any element. Residents' compliance was high for most elements of the PPPs for POAGS. We identified elements with poor compliance especially regarding patient education. Adherence to AAO PPPs can be a helpful method of assessing resident performance.

Optical coherence tomography to distinguish Parkinson disease versus supranuclear progressive palsy

PurposeThe aim of the study was to examine patterns of peripapillary andretinal layer damage as a potential marker of neurodegeneration in Parkinson'sdisease (PD) compared to progressive supranuclear palsy (PSP) with 2 SD‐ OCTdevices.MethodsPeripapillary retinal nerve fiber layer (pRNFL), macular thickness (MT)and ganglion cell layer inner plexiform analysis (GCA) by Cirrus and pRNFL analysis and automaticsingle retinal layers macular segmentation by Spectralis were used to evaluate38 patients with PD and 15 patients with PSP.ResultsMean average and superior RNFL by Cirrus were thicker in PD compared to PSP (p = 0.001). The mean central, superior, supero‐temporal and infero‐temporal RNFL thicknesses by Spectralis were also significantly higher in PD compared to PSP (p &lt; 0.05). Using Cirrus OCT, mean MT and all measurements by GCA were significantly higher in PD compared to PSP (p &lt; 0.002). The AUC was larger for minimum GCIPL (0.912) than for average GCIPL thickness (0.850). A minimum GCIPL thickness cut‐off value of 69 μm, was able to differentiate PSP from PD (Sensitivity: 91.7%; Specificity: 72.7%). Minimum and average GCIPL thicknesses significantly correlated with Hoehn and Yahr score (p &lt; 0.05), and with UPDRS (Unified Parkinson's Disease Rating Scale) (p &lt; 0.005).ConclusionsThedifferential diagnosis of Parkinsonian disorders is clinical one and not alwayseasy, especially at the onset of disease. In thecurrent study, the minimum GCIPL thickness was the most sensitiveparameter to differentiate PD from PSP and it was significantly correlated withneurological score. These findings may facilitate the differential diagnosisand give insight into the degenerative processes of atypical parkinsonian syndromes.

Optic nerve head, retinal nerve fiber layer and macular thickness analysis in restless legs syndrome

PurposeThe human retina contains dopaminergic neurons within the inner retinal layer. Several studies demonstrated dopaminergic neuronal loss in Parkinson's disease (PD) using optical coherence tomography (OCT). Hypothetically, restless legs syndrome (RLS) may have an underlying dopaminergic mechanism and a probable relation to PD is assumed. Therefore, we aimed to analyze retinal morphology in RLS patients. MethodsIn this cross-sectional study we used spectral domain OCT to measure the features of various retinal layers such as thicknesses of peripapillary retinal nerve fiber layer (RNFL), macular and foveal layers, ganglion cell complex (GCC), and optic nerve head parameters of 36 patients with idiopathic RLS, together with 36 age and sex-matched controls. Differences in the thicknesses of RNFL, macula, GCC and optic disc parameters are statistically compared between patients and controls. ResultsThe average peripapillary RNFL thickness, mean macular volume and total retinal thickness were reduced in RLS compared with healthy controls (p = 0.032, p = 0.029, and p = 0.026, respectively). After Bonferroni correction, only the reduction in the inferior inner and outer quadrants of the macula remained significant (p = 0.0040, for both). Optic nerve head parameters (cup volume, cup/disc area ratio, rim area and disc area) and GCC thickness showed no significant difference between patients and healthy controls. ConclusionOur study revealed significant retinal thinning in the macula region in RLS. Our results may support the dopaminergic dysfunction in the pathogenesis of RLS. Prospective longitudinal studies with a larger sample are needed to corroborate our results.

Effect of Head Tilt and Ocular Compensatory Mechanisms on Retinal Nerve Fiber Layer Measurements by Cirrus Spectral Domain and Spectralis Optical Coherence Tomography in Normal Subjects.

To determine the effect of head tilt and ocular compensatory mechanisms on retinal nerve fiber layer (RNFL) thickness measurements using the Cirrus and Spectralis spectral-domain optical coherence tomography (OCT) in healthy eyes. Our secondary objective was to assess the visual influence on ocular compensatory mechanisms during head tilt. This is a prospective, observational study. A single randomly selected eye was scanned undilated in 3 positions (baseline, right, and left tilt) using both machines. In addition, patching was also done for the contralateral eye during head tilt and RNFL measurements repeated. The paired t test was used to analyze effect on RNFL thickness. One-way repeated-measures analysis of variance was used to compare differences in RNFL measurements. In Cirrus OCT RNFL analysis, ipsilateral head tilt resulted in superior thinning and temporal thickening, whereas contralateral head tilt resulted in inferior thinning, nasal thickening, as well as temporal thickening (all P<0.05). Head tilt did not cause any significant change in RNFL thickness with Spectralis OCT (P>0.05). Patching the contralateral eye also did not alter Cirrus RNFL measurement errors due to head tilt. Head tilt can affect the measurement of the RNFL thickness in Cirrus OCT, and ocular compensatory mechanisms were not sufficient to prevent this. In contrast, Spectralis OCT RNFL thickness measurements were not affected by head tilt. Patching the contralateral eye during head tilt in Cirrus OCT also did not affect RNFL variability. The visual influence on ocular compensatory mechanisms during head tilt appears insignificant.

Une cause rare de neuropathie optique : le manioc

Cassava root is a staple food for almost 500 million people worldwide. Excessive consumption of it is a rare cause of optic neuropathy. Ten patients diagnosed with cassava root related optic neuropathy were included in this retrospective study. Diagnostic criteria were a bilateral optic neuropathy preceded by significant cassava root consumption. Differential diagnoses were excluded through a neuro-ophthalmic examination, blood tests and a brain MRI. All patients had visual field examination and OCT retinal nerve fiber layer (RNFL) analysis as well as an evaluation of their cassava consumption. All patients had a bilateral optic nerve head atrophy or pallor predominantly located into the temporal sector. Visual field defects consisted of a central or cecocentral scotoma for all patients. RNFL showed lower values only in the temporal sector. Mean duration of cassava consumption prior to the appearance of visual symptoms was 22.7±11.2 years with a mean of 2.57±0.53 cassava-based meals per week. Cassava related optic neuropathy is possibly due to its high cyanide content and enabled by a specific amino-acid deficiency. Cassava root chronic consumption is a rare, underappreciated cause of optic neuropathy and its exact mechanism is still uncertain.

Progressive Loss of Retinal Ganglion Cells and Axons in Nonoptic Neuritis Eyes in Multiple Sclerosis: A Longitudinal Optical Coherence Tomography Study.

To examine the rate of retinal ganglion cell (RGC) layer and retinal nerve fiber layer (RNFL) changes in nonoptic neuritis (NON) eyes of relapsing remitting multiple sclerosis (RRMS) patients, and to find a specific imaging parameter useful for identifying disease progression. Forty-five consecutive RRMS patients and 20 age- and sex-matched healthy subjects were enrolled. All patients were followed up for 3 years with annual optical coherence tomography (OCT) scans, which included a peripapillary ring scan protocol for RNFL analysis and a macular radial star-like scan to obtain RGC/inner plexiform layer (IPL) thickness measures. Healthy controls were scanned twice, 3 years apart. Retinal ganglion cell/inner plexiform layer and temporal RNFL (tRNFL) demonstrated highly significant thinning (P < 0.01), but all nasal segments and global RNFL (gRNFL) were not significantly different from normal controls. While receiver operating characteristics (ROC) analysis showed no advantage of RGC/IPL over tRNFL in cross-sectional detection of thinning, cut-off point based of fifth percentile in healthy controls demonstrated higher rate of abnormality for RGC/IPL. There was a significant progressive loss of RGC/IPL and tRNFL during the follow-up period. The largest thickness reduction was observed in tRNFL. ROC analysis demonstrated that tRNFL provided better sensitivity/specificity for detecting change over time than RGC/IPL (area under the curve [AUC] 0.78 vs. 0.52), which was confirmed by higher detection rate when 95th percentile of progression in healthy controls was used as a cut-off. This study confirmed significant thinning of RGC/IPL and tRNFL in NON eyes of RRMS patients. Progressive losses were more apparent on tRNFL, while RGC/IPL showed less change over the follow-up period.

Asymmetry of Retinal Nerve Fiber Layer and Posterior Pole Asymmetry Analysis Parameters of Spectral Domain Optical Coherence Tomography in Children

ABSTRACTPurpose: To determine inter- and intraocular differences in the retinal nerve fiber (RNFL) and posterior pole asymmetry analysis (PPAA) macular thickness parameters in children using spectral domain optical coherence tomography. Method: A prospective, cross-sectional study involving 126 subjects between the age group of 5–15 years received a standardized eye examination including spectral domain optical coherence tomography for retinal nerve fiber layer and macular thickness measurements. Asymmetry was calculated as the difference between the right and left eyes as well as the superior and inferior area of one randomly selected eye for each subject. Normal ranges were established as the 2.5 and the 97.5 percentiles. Correlation between the right and left eyes were assessed by intraclass correlation coefficients. Results: The difference in the average and superior RNFL between the right and the left eye was not statistically significant. The interocular 2.5 and 97.5 percentile limits for RNFL thickness and total PPAA macular thickness were –7.75 to 12.5 microns and –9 to 21 microns, respectively. The 2.5 and 97.5 percentile limits of the intraocular superior-inferior area difference for the RNFL thickness and PPAA macular thickness were –40 to 37 microns and –32 to 38 microns, respectively. A strong correlation for all parameters between the right and the left eye was seen. Conclusion: The normal interocular RNFL and PPAA macular thickness asymmetry should not exceed 12.5 microns and 21 microns, respectively. Similar intraocular limits for superior-inferior asymmetry should not exceed 40 and 38 microns, respectively.

Can Automated Imaging for Optic Disc and Retinal Nerve Fiber Layer Analysis Aid Glaucoma Detection?

PurposeTo compare the diagnostic performance of automated imaging for glaucoma.DesignProspective, direct comparison study.ParticipantsAdults with suspected glaucoma or ocular hypertension referred to hospital eye services in the United Kingdom.MethodsWe evaluated 4 automated imaging test algorithms: the Heidelberg Retinal Tomography (HRT; Heidelberg Engineering, Heidelberg, Germany) glaucoma probability score (GPS), the HRT Moorfields regression analysis (MRA), scanning laser polarimetry (GDx enhanced corneal compensation; Glaucoma Diagnostics (GDx), Carl Zeiss Meditec, Dublin, CA) nerve fiber indicator (NFI), and Spectralis optical coherence tomography (OCT; Heidelberg Engineering) retinal nerve fiber layer (RNFL) classification. We defined abnormal tests as an automated classification of outside normal limits for HRT and OCT or NFI ≥ 56 (GDx). We conducted a sensitivity analysis, using borderline abnormal image classifications. The reference standard was clinical diagnosis by a masked glaucoma expert including standardized clinical assessment and automated perimetry. We analyzed 1 eye per patient (the one with more advanced disease). We also evaluated the performance according to severity and using a combination of 2 technologies.Main Outcome MeasuresSensitivity and specificity, likelihood ratios, diagnostic, odds ratio, and proportion of indeterminate tests.ResultsWe recruited 955 participants, and 943 were included in the analysis. The average age was 60.5 years (standard deviation, 13.8 years); 51.1% were women. Glaucoma was diagnosed in at least 1 eye in 16.8%; 32% of participants had no glaucoma-related findings. The HRT MRA had the highest sensitivity (87.0%; 95% confidence interval [CI], 80.2%–92.1%), but lowest specificity (63.9%; 95% CI, 60.2%–67.4%); GDx had the lowest sensitivity (35.1%; 95% CI, 27.0%–43.8%), but the highest specificity (97.2%; 95% CI, 95.6%–98.3%). The HRT GPS sensitivity was 81.5% (95% CI, 73.9%–87.6%), and specificity was 67.7% (95% CI, 64.2%–71.2%); OCT sensitivity was 76.9% (95% CI, 69.2%–83.4%), and specificity was 78.5% (95% CI, 75.4%–81.4%). Including only eyes with severe glaucoma, sensitivity increased: HRT MRA, HRT GPS, and OCT would miss 5% of eyes, and GDx would miss 21% of eyes. A combination of 2 different tests did not improve the accuracy substantially.ConclusionsAutomated imaging technologies can aid clinicians in diagnosing glaucoma, but may not replace current strategies because they can miss some cases of severe glaucoma.

Analyse des fibres nerveuses rétiniennes péripapillaires ajustée selon l’angle papillo-maculaire en tomographie par cohérence optique en domaine spectral. Étude préliminaire

Circumpapillary retinal nerve fiber layer (cpRNFL) analysis by spectral domain optical coherence tomography (SD-OCT) has become essential for the assessment of glaucoma patients. The foveal projection is conventionally below the disc plane, creating an angle with the horizontal meridian, the disc-fovea angle. The purpose of this study is to evaluate the role of adjustment of cpRNFL analysis based on this angle. This study concerns 40 control eyes and 55 eyes affected with and followed for primary open angle glaucoma (POAG). After precise localization of the optic disc center and the axis connecting it to the center of the fovea, a circular peripapillary scan is performed with Spectralis OCT (Heidelberg Engineering, Germany). The mean thickness in each of six papillary sectors and the global mean thickness of the cpRNFL were evaluated. The ROC (receiver operating characteristic) analysis evaluated the diagnostic capabilities of the various sectors before and after adjustment of the analysis for the disc-fovea angle. The disc-fovea angle was not different between the two groups (-7.0 ± 1.2° for controls vs. -6.6 ± 1.2° for POAG, P=0.70). There is a significant variance of this angle in both groups (the angle varies in the control group between -22.5° to +1.8° and in the POAG group between -18° to +2.4°). The global mean and inferior temporal (IT) thickness of the cpRNFL show the best diagnostic performance. Adjustment for disc-fovea angle does not increase the diagnostic accuracy of the various sectors analyzed. Although there is an increase in the area under the curve for the IT sector after adjustment, it is not statistically significant (0.910 ± 0.056 vs. 0.936 ± 0.045, P=0.06). There is a significant variation in disc-fovea angle. In this study, accounting for it does not significantly improve the diagnostic capabilities of cpRNFL in patients with POAG.

LOXL1 gene analysis in Turkish patients with exfoliation glaucoma.

The purpose of this study is to evaluate whole lysyl oxidase like 1 (LOXL1) gene by sequence analysis in Turkish patients with exfoliation glaucoma (XFG). A total of 48 (35 male, 13 female) patients with XFG were enrolled. Besides routine ophthalmological examination, peripapillary retinal nerve fibre layer (RNFL) analysis with optic coherence tomography was performed. Blood samples of 2ml with EDTA were obtained and sent to Medical Genetics Department, Molecular Genetics Laboratory for LOXL1 polymorphism (PCR and agarose gel imaging) analysis. The role of the detected changes on disease severity was evaluated. No LOXL1 gene mutations in any of the patients were detected. Three types of single-nucleotide polymorphisms (SNPs) including R141L(rs1048661), A320A(rs41435250), and F184F were detected in 17 (35.3%) patients. When compared, SNP-positive patients had thinner RNFL than SNP-negative patients (64.5±17.6 and 66.1±20.4µ, respectively), and SNP-positive patients had higher cupping/disc ratio than SNP-negative patients (0.76±0.2 and 0.70±0.3, respectively). However, both values were not statistically significant (p=0.966 and p=0.539, respectively). When compared, R141L-positive patients had significantly thinner cornea thickness (516.11±30.3µ) than R141L-negative patients (556.69±27.2µ) (p=0.004). There was not any statistical significant difference in the means of age, gender, BCVA, MD, PSD, IOP, number of hypotensive agents, and percent of glaucoma surgery (p>0.05). In this study group of Turkish population, no LOXL1 mutations were found. No associations between the defined SNPs (A320A, R141L and F184F) and the severity of the disease were detected.

Macular Ganglion Cell Layer Assessment to Detect Glaucomatous Central Visual Field Progression

PurposeTo investigate the use of ganglion cell inner plexiform layer (GC-IPL) thickness, as measured by spectral domain optical coherence tomography, to detect central visual field (VF) progression.MethodsThis study included 384 eyes from 384 patients (219 preperimetric and 165 perimetric glaucomatous eyes; average follow-up, 4.3 years). Photographic assessment of retinal nerve fiber layer (RNFL) and serial VF analysis were performed to detect glaucoma progression in the central (within 10°) area. Study inclusion required at least five serial spectral domain optical coherence tomography exams at different visits. The long-term test-retest variability of average GC-IPL thicknesses was calculated in 110 stable preperimetric glaucomatous eyes. The sensitivity and specificity of GC-IPL measurements for the detection of central VF progression were calculated in an event-based analysis using the calculated variability as a cut-off and were compared with those of central RNFL photographic assessment.ResultsThe intersession test-retest variability, defined as the 95% confidence interval, was 1.76 µm for average GC-IPL thickness. The sensitivity and specificity of the average GC-IPL thickness for detecting central VF progression were 60.7% and 78.9%, respectively. Among six sectors, the inferonasal GC-IPL sector showed the highest sensitivity (53.6%). The sensitivity of the ≥1 sector GC-IPL to detect central VF progression was significantly higher than that of central RNFL photographic progression (p = 0.013). Other GC-IPL parameters showed comparable sensitivity and specificity to detect central VF progression compared with RNFL photographic progression.ConclusionsSerial GC-IPL measurements show comparable performance in the detection of central glaucomatous VF progression to RNFL photographic assessment.