Average Peripapillary Retinal Nerve Fiber Layer Thickness Research Articles

Normative Reference Ranges for the Retinal Nerve Fiber Layer, Macula, and Retinal Layer Thicknesses in Children

To establish a normative database of peripapillary retinal nerve fiber layer (RNFL) thickness, macular thickness, and retinal layer thickness in healthy North American children, using spectral-domain optical coherence tomography (SD OCT). Prospective cross-sectional study. This institutional study enrolled 83 healthy children (aged 5-15 years) as volunteer research subjects at the Retina Foundation of the Southwest (Dallas, Texas); all had normal visual acuity. Imaging was accomplished with the Spectralis SD OCT. Peripapillary RNFL thickness and macular thickness were assessed for 1 eye of each child using the Heidelberg Spectralis SD OCT software. Thicknesses of individual retinal layers and layer combinations were assessed using custom software to segment the line scans obtained with the Spectralis SD OCT. Average global peripapillary RNFL thickness was 107.6 ± 1.2μm and average central subfield macular thickness was 271.2 ± 2.0μm. Peripapillary RNFL thickness was thicker than has been reported in adults, particularly the superior and inferior sectors, and central subfield macular thickness was significantly correlated with age. While the thickness of most retinal layers was comparable with those of adults, the outer segment layer was 36% thinner in children than in adults. SD OCT can be used to assess peripapillary RNFL thickness, macular thickness, and retinal layer thickness in children as young as 5 years. Pediatric means and normative reference ranges are provided for each measurement. The values presented herein can be used as a standard with which to compare those of children suspected of having retinal or optic nerve abnormalities.

Peripapillary Retinal Nerve Fiber Layer Thickness in Children with Iron Deficiency Anemia

To evaluate peripapillary retinal nerve fiber layer (RNFL) thickness in children with iron deficiency anemia (IDA) in comparison with healthy controls and to investigate the correlation between peripapillary RNFL thicknesses and the hematologic parameters in these subjects. Forty eyes of 40 children with a diagnosis of IDA (anemic group) and 40 eyes of 40 age- and sex-matched healthy children (control group) were enrolled in this study. Peripapillary RNFL thickness measurements were performed using Cirrus HD optical coherence tomography (OCT). Mean age of each group was 11.3±2.7 years. Average RNFL and RNFLs of superior and inferior quadrants were significantly thinner in the anemic group than in the control group (p=0.006, p=0.005, and p=0.005, respectively). In addition, average peripapillary RNFL thickness and RNFL thicknesses of superior, inferior, and temporal quadrants were correlated with hemoglobin levels (r1=0.734, p1<0.001, r2=0.456, p2=0.005, r3=0.598, p3<0.001, r4=0.349, p4=0.037, respectively) in anemic group. CONCLUSIONS. We found that children with IDA had different peripapillary RNFL profile measured by Cirrus HD spectral-domain OCT. We caution ophthalmologists when they measure RNFL thickness in children to diagnose glaucoma or other neuro-ophthalmic disorders.

The relationship between the optical density of cataract and its influence on retinal nerve fibre layer thickness measured with spectral domain optical coherence tomography

The purpose of this study was to model the influence of cataract on Spectral Domain Optical Coherence Tomography (SDOCT) image quality and Retinal Nerve Fibre Layer (RNFL) thickness measurements. SDOCT images, made with two different devices (3DOCT-1000, Topcon and Cirrus HD-OCT), before and after cataract surgery were compared and judged against measurements from normal subjects using artificial filters simulating the effects of cataract. Optical density of the images was calculated based on a mathematical model described previously. In total, forty-eight eyes were included for pre- and postoperative cataract extraction measurements. OCT image quality significantly (p < 0.001) improved postoperative and postoperative RNFL thickness was significantly (p < 0.001) thicker in both groups of patients. The measurements using artificial filters showed a rather precise linear relation between change in filter induced optical density and change in RNFL thickness (R = 0.941, p < 0.001 for 3DOCT-1000 and R = 0.785, p < 0.001 for Cirrus HD-OCT). For the patient groups, the relation was less marked, 3DOCT-1000 Rs = 0.697, p < 0.03 and Cirrus HD-OCT Rs = 0.444, p < 0.03. The predictive potential based on the found linear relationship between OCT-effective optical density of cataract and the cataract-induced underestimation was however limited, and mean difference ± SD between predicted and measured RNFL thickness were 1.68 ± 7.55 (3DOCT-1000) and 3.71 ± 2.97 (Cirrus HD-OCT) micron. A linear relationship exists between OCT-effective optical density of cataract and underestimation of RNFL thickness measured with OCT. This finding holds promise to correct for cataract-induced changes in RNFL measurements, but will differ for each type of OCT device.

Relationship between retinal nerve fiber layer thickness and the duration and severity of parkinson disease

AbstractPurpose To determine in patients with Parkinson disease (PD) the correlation between peripapillary retinal nerve fiber layer (RNFL) thickness and macular thickness and volume, with the duration and severity of the neurological disorder.Methods 102 eyes corresponding to patients affected by PD were compared with 97 eyes of age‐matched controls. In all individuals peripapillary RNFL thickness, macular thickness and volume were measured by optical coherence tomography (OCT).Results We found statistically significant differences in all parameters of peripapillary RNFL thickness between Parkinson patients and controls. In all quadrants RNFL thickness was significantly lower in PD patients (p = 0.017 in temporal RNFL and p &lt;0.001 in the other quadrants). Nevertheless, macular thickness and volume did not reveal any statistically significant reduction in PD patients when compared with controls (p&gt;0.05). Furthermore, we found a significant inverse correlation between disease duration (years) and disease severity measured by Unified Parkinson’s Disease Rating Scale and overall peripapillary RNFL thickness (p=0.002 and p &lt;0.001, respectively), indicating that the more years of illness or greater UPDRS score, the lower peripapillary RNFL thickness.Conclusion PD patients showed a statistically significant reduction in peripapillary RNFL thickness evaluated by OCT in terms of evolution and severity of PD. That means that the further evolution of PD, the lower average peripapillary RNFL thickness. Our results suggest that RNFL thickness measured by OCT might be used as a biomarker of PD severity progression or even as an indicator of good response to long‐term treatment.

Optic Nerve Head, Retinal Nerve Fiber Layer, and Macular Thickness Measurements in Young Patients with Retinitis Pigmentosa

Purpose: To evaluate optic nerve head (ONH) parameters, peripapillary retinal nerve fiber layer (RNFL) thickness, and macular thickness by using Cirrus HD spectral-domain optical coherence tomography (OCT) in young patients with retinitis pigmentosa (RP).Methods: ONH parameters, RNFL thickness, and macular thickness were measured and compared between 36 eyes from 36 young RP patients (RP group; mean age, 23.08 years) and 70 eyes from 70 healthy young subjects (control group; mean age, 22.66 years) using Cirrus HD-OCT. The effects of the presence of optic disc pallor and the severity of visual field (VF) defects on OCT parameters were also evaluated.Results: The RP group had a greater rim area, smaller cup-to-disc ratio, smaller cup volume, thicker RNFL, and thinner macula than the control group (p ≤ 0.024). ONH parameters were not affected by the presence of optic disc pallor (p ≥ 0.239). Eyes with more severe VF defects (mean deviation ≤ −13.88 dB) had thinner average macular areas than eyes with less severe VF defects (mean deviation ≥ −13.88 dB; p = 0.002). Meanwhile, the ONH parameters and average peripapillary RNFL thickness were not significantly different between the two groups (p ≥ 0.275).Conclusions: Young eyes with RP exhibited different OCT parameters compared to healthy eyes. Among the various OCT parameters, only macular thickness was associated with disease severity. These findings should be considered when evaluating young RP patients.

Quantification of retinal nerve fiber layer thickness using spectral domain optical coherence tomography in normal Indian population

The purpose of this study was to measure peripapillary retinal nerve fiber layer thickness (RNFLT) using spectral domain optical coherence tomography (SD-OCT) in normal Indian eyes, for which, 210 normal volunteers were recruited. One eye of each subject underwent RNFL scanning at 3.4 mm circle diameter around optic nerve using SD OCT. The data were analyzed to determine RNFLT in the sample population and its variation with age and gender. The average peripapillary RNFLT was 114.03 ± 9.59 μm. There was no effect of gender on RNFLT parameters. Age had significant negative correlation with average (P = 0.005), superior (P = 0.04), temporal (P = 0.049), and nasal quadrants (P = 0.01) RNFLT. Inferior quadrant RNFLT also had a negative correlation with age, but it was not statistically significant (P = 0.15).

Acute Mountain Sickness and Retinal Evaluation by Optical Coherence Tomography

Acute mountain sickness (AMS), the commonest form of altitude illness, might represent early-stage high altitude cerebral edema (HACE). Optical coherence tomography (OCT) was used to evaluate optic nerve head (ONH) consequences following a sojourn to extreme altitude. This prospective study included 4 high-altitude expeditions in Himalayas. Twenty-four eyes of 12 healthy male climbers underwent baseline and postexpedition complete ophthalmic evaluation, including OCT to measure the peripapillary retinal nerve fiber layer (RNFL) thickness, ONH parameters, and macular thickness and volume. Lake Louise Scoring (LLS) self-report questionnaire was used to estimate AMS severity. All mountaineers experienced symptoms of AMS (LLS: 5.1±1.1, range 4.0-7.0). Average peripapillary RNFL thickness showed a significant increase in postexpedition examination (94±23 µm, 47-115), compared with baseline values (89±19 µm, range 45-114) (p=0.034). Superior (p=0.036) and temporal (p=0.010) quadrants also showed an increased RNFL thickness following exposure to high altitude. Vertical integrated rim area (VIRA) was significantly higher in postexpedition examination (0.71±0.43 mm(3), 0.14-1.50) than in baseline examination (0.51±0.26 mm(3), 0.11-1.00) (p=0.002). Horizontal integrated rim width was significantly higher in postexpedition examination (1.90±0.32 mm(2), range 1.37-2.34) than in baseline examination (1.77±0.27 mm(2), 1.27-2.08) (p=0.004). There was no correlation between LLS and OCT parameters (p>0.05). In climbers with AMS, OCT was able to detect subtle increases in the peripapillary RNFL thickness and in some ONH measurements, even in absence of HACE and papilledema. These changes might be a sensitive parameter in physiologic acclimatization and in the pathogenesis of AMS.

Evaluation of the Nerve Fiber Layer and Macula in the Eyes of Healthy Children Using Spectral-Domain Optical Coherence Tomography

To determine the normative values of the peripapillary retinal nerve fiber layer (RNFL), macular thickness, and macular volume in healthy children using spectral-domain optical coherence tomography (SD-OCT) and analyze the correlation of such values with age, refraction error, and biometric measurements. Observational case series. This institutional study involved 107 eyes from 107 healthy pediatric patients (54 female, 53 male) with ages between 6 and 16 years. After the biometric measurements and refractive error values (in spherical equivalent) of the cases were obtained, the peripapillary RNFL, macular thickness, and macular volume values were calculated using the Spectralis OCT device. Among the study group, with an average age of 10.46 ± 2.94 years, the average axial length (AL) was 23.33 ± 0.89 mm; the average spherical equivalent (SE) value was -0.27 ± 0.99 diopter. The average peripapillary RNFL thickness was 106.45 ± 9.41 μm; the average macular thickness was 326.44 ± 14.17 μm; and the average macular volume was 0.257 ± 0.011 mm(3). The aforementioned OCT measurements were not significantly correlated with age, SE, or AL values (P > .05 for all). This study reports SD-OCT findings among healthy pediatric cases. SD-OCT can be reliably used for pediatric patients because of its short exposure time and high degree of image resolution.

Parkinson´s disease and retinal optical coherence tomography

AbstractPurpose The aim of the study was to assess the retinal measurements and optic nerve head (ONH) morphology in patients with Parkinson's disease (PD) and to determine whether there is any correlation among these parameters and the disease´s duration.Methods Thirty patients affected by PD (mean age 67,3 ± 8,4; range: 49 ‐ 83) were compared with 28 age‐matched controls. In all subjects, peripapillary retinal nerve fiber layer (RNFL) thickness, ONH measurements, and macular thickness and volume were measured by optical coherence tomography (OCT).Results PD patients showed a statistically significant reduction of the overall peripapillary RNFL thickness [95±9µm, range: 73‐117] compared with those values observed in control eyes [103±7µm, range:87‐117] (p&lt;0.0001, Mann‐Whitney U test). Furthermore, a statistically significant reduction of RNFL thickness was observed in nasal [74±20µm, range:18‐114](p=0.004), inferior [118±14µm, range:88‐147] (p&lt;0.0001) and superior quadrants [120±13µm, range:88‐145] in PD patients when compared with controls [84±14µm, range:54‐106], [132±14µm, range:101‐165] and [125±13µm, range:101‐151] respectively (p=0.023; Mann‐Whitney U test). The temporal peripapillary quadrant, ONH measurements, macular thickness and volume did not reveal any statistically significant differences between both groups.Conclusion PD patients show a decreased peripapillary RNFL thickness evaluated by OCT. We also observe that the further evolution of PD, the lower average peripapillary RNFL thickness. Our results suggest that axonal degeneration could be present in the retina of PD patients and that RNFL thickness measured by OCT could be used as a biomarker for early diagnosis and for monitoring PD progression.

Macular and peripapillary retinal nerve fibre layer thickness in adults with amblyopia

Objective To evaluate macular and peripapillary retinal nerve fiber layer (RNFL) thickness in amblyopic eyes compared to the fellow eye. Design Cross-sectional study. Participants 30 patients (60 eyes) older than 18 years of age with amblyopia. Methods Inclusion criteria included individuals older than 18 years, amblyopia, and best-corrected visual acuity (BCVA) ≤20/40. A complete medical history was taken and an eye examination carried out. Optical coherence tomography (OCT) was carried out on both eyes of all patients. Exclusion criteria included intraocular pressure (IOP) >23 mm Hg and eye pathology that may affect OCT measurements. The primary outcome measures were foveal thickness and average peripapillary RNFL thickness, which were compared using a paired t test. Quadrants in peripapillary scans and concentric rings in macular scans were analyzed. Results The average age was 56 years (range = 33–82 years). Visual acuity ranged from 20/40 to 20/4000 (mean = 20/275). The average peripapillary RNFL thickness was 90.6 μm (SD = 9.6 μm) in the amblyopic eye and 90.1 μm (SD = 12.1 μm) in the fellow eye ( p = 0.64). The average macular thickness in amblyopic eyes was 260.1 μm (SD = 32.0 μm), and 254.7 μm (SD = 32.5 μm) in fellow eyes ( p = 0.10). No statistical difference existed between peripapillary quadrants or macular concentric rings. These differences were smaller when the strabismic amblyopes were isolated. Conclusions There does not seem to be a difference in peripapillary RNFL or macular thickness between the amblyopic eye and fellow eye.

Diagnostic Power of Optic Disc Morphology, Peripapillary Retinal Nerve Fiber Layer Thickness, and Macular Inner Retinal Layer Thickness in Glaucoma Diagnosis With Fourier-domain Optical Coherence Tomography

To evaluate the capability of the optic disc, peripapillary retinal nerve fiber layer (P-RNFL), macular inner retinal layer (M-IRL) parameters, and their combination obtained by Fourier-domain optical coherent tomography (OCT) in differentiating a glaucoma suspect from perimetric glaucoma. Two hundred and twenty eyes from 220 patients were enrolled in this study. The optic disc morphology, P-RNFL, and M-IRL were assessed by the Fourier-domain OCT (RTVue OCT, Model RT100, Optovue, Fremont, CA). A linear discriminant function was generated by stepwise linear discriminant analysis on the basis of OCT parameters and demographic factors. The diagnostic power of these parameters was evaluated with receiver operating characteristic (ROC) curve analysis. The diagnostic power in the clinically relevant range (specificity ≥ 80%) was presented as the partial area under the ROC curve (partial AROC). The individual OCT parameter with the largest AROC and partial AROC in the high specificity (≥ 80%) range were cup/disc vertical ratio (AROC = 0.854 and partial AROC = 0.142) for the optic disc parameters, average thickness (AROC = 0.919 and partial AROC = 0.147) for P-RNFL parameters, inferior hemisphere thickness (AROC = 0.871 and partial AROC = 0.138) for M-IRL parameters, respectively. The linear discriminant function further enhanced the ability in detecting perimetric glaucoma (AROC = 0.970 and partial AROC = 0.172). Average P-RNFL thickness is the optimal individual OCT parameter to detect perimetric glaucoma. Simultaneous evaluation on disc morphology, P-RNFL, and M-IRL thickness can improve the diagnostic accuracy in diagnosing glaucoma.

Evidence for retrochiasmatic tissue loss in Leber's hereditary optic neuropathy

Patients with Leber's hereditary optic neuropathy (LHON) have loss of central vision with severe damage of small-caliber fibers of the papillomacular bundle and optic nerve atrophy. The aim of this study was to define the presence and topographical distribution of brain grey matter (GM) and white matter (WM) injury in LHON patients using voxel-based morphometry (VBM). The correlation of such changes with neuro-ophthalmologic findings and measurements of peripapillary retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT) was also assessed. Dual-echo and fast-field echo scans were acquired from 12 LHON patients and 12 matched controls. VBM analysis was performed using SPM5 and an ANCOVA model. A complete neuro-ophthalmologic examination, including standardized automated Humphrey perimetry as well as average and temporal peripapillary RNFL thickness measurements were obtained in all the patients. Compared with controls, average peripapillary RNFL thickness was significantly decreased in LHON patients. LHON patients also had significant reduced GM volume in the bilateral primary visual cortex, and reduced WM volume in the optic chiasm, optic tract, and several areas located in the optic radiations (OR), bilaterally. Visual cortex and OR atrophy were significantly correlated with average and temporal peripapillary RNFL thickness (P < 0.001; r values ranging from 0.76 to 0.89). Brain damage in patients with LHON is not limited to the anterior visual pathways, but extends posteriorly to the OR and the primary visual cortex. Such a damage to the posterior parts of the visual pathways may be due either to trans-synaptic degeneration secondary to neuroaxonal damage in the retina and optic nerve or to local mitochondrial dysfunction.

Rigidity of Retinal Vessels in Patients with Multiple Sclerosis

The aim of this study was to analyze pulse wave propagation in the ocular circulation by assessing the phase delay between retinal arterioles and venules and calculating the pulse delay between the retinal and choroidal circulations in MS patients and in control subjects. Twenty patients with multiple sclerosis (38.3 +/- 6.2 years) and twenty healthy subjects (37.4 +/- 15.2 years) were examined with the Retinal Vessel Analyzer. In addition, an average peripapillary RNFL (retinal nerve fiber layer) thickness was measured by means of ocular coherence tomography in MS patients. The phase delay between the arteriole and venule pulsations was assessed at three sites: in the close retinal vicinity of the disc, 1 - 2 disc diameters and 3 - 4 disc diameters away from the disc. Assuming that venules are counterphased to the choroidal circulation, a choroid-to-retina pulse delay was calculated. The choroid-to-retina pulse delay was 0.26 +/- 0.11, 0.27 +/- 0.13 and 0.34 +/- 0.15 sec in eyes with history of optic neuritis (ON-eyes); in eyes of MS patients without such a history (non-ON eyes) the corresponding values were 0.27 +/- 0.14, 0.29 +/- 0.11 and 0.30 +/- 0.15 sec, and in control eyes 0.32 +/- 0.19, 0.38 +/- 0.16 and 0.45 +/- 0.20 sec, respectively, at three sites centrifugal from the disc. The choroid-to-retina pulse delay was significantly longer in healthy control eyes than both in ON eyes (p = 0.012) and non-ON eyes of MS patients (p = 0.004). The interocular difference of the choroid-to-retina pulse delay and OCT RNFL thickness showed a significant correlation in MS patients (Pearson r = 0.54, p = 0.015; Spearman R = 0.66, p = 0.0016). Patients with multiple sclerosis seem to demonstrate an increased rigidity of the retinal vessels. The interocular difference in retinal vessel rigidity was significantly correlated with the interocular difference in RNFL thickness in MS patients.

The role of Humphrey Matrix testing in the early diagnosis of retinopathy in type 1 diabetes

Aim:The aim of the study was to investigate the role of Humphrey Matrix threshold testing in the detection of early functional retinal impairment in subjects with type 1 diabetes mellitus...

Peripapillary Nerve Fiber Layer Thickness Measured by Optical Coherence Tomography in Patients With No Light Perception From Long-Standing Nonglaucomatous Optic Neuropathies

The residual peripapillary retinal nerve fiber layer thickness (PRNFLT) corresponding to no light perception vision from long-standing nonglaucomatous optic neuropathies has not been documented. Such a benchmark would be useful information because PRNFLT is being used as an indicator of the visual recovery potential in patients with optic neuropathies. By means of optical coherence tomography (OCT) using a fast RNFL thickness protocol, we determined the PRNFLT in 8 patients with no light perception (NLP) for at least 1 year from acquired nonglaucomatous optic neuropathies. All patients underwent an assessment of visual acuity, color vision, visual field, pupillary reactions to light stimulation, and ophthalmoscopy. Four of the 8 patients had a normal fellow eye. The average PRNFLT in the 4 normal eyes was 97.90 microm (range 94.82-100.89 microm), whereas the average PRNFLT in 8 of the 9 eyes with NLP was 45.42 microm (range 37.65-51.46 microm). Eyes with long-standing NLP vision from nonglaucomatous optic neuropathies retain a residual PRNFLT of about 45 microm as measured by OCT. This should be taken into consideration when using PRNFLT to assess visual prognosis in patients with poor vision from various optic neuropathies.

Optical Tomography–Measured Retinal Nerve Fiber Layer Thickness in Normal Latinos

To measure retinal nerve fiber layer (RNFL) thickness in normal Latinos using optical coherence tomography (OCT). Three hundred twelve Latino participants, aged 40 years or more, underwent a detailed ophthalmic examination, including measurement of visual acuity, intraocular pressure, visual field perimetry, and stereoscopic optic disc photography. None of the participants had any evidence of ocular hypertension, glaucoma, or other ocular disease. Nine scans were performed on one eye of each participant by optical coherence tomography (OCT Model 2000; Carl Zeiss Meditec, Dublin, CA, software version A 6.1): three circumferential peripapillary scans and six radial scans of the macula. The average RNFL thicknesses in the peripapillary region and macula were measured. A paired t-test and linear regression analyses were used to analyze the data. The mean age of the participants was 52 years (range, 40-79 years). The average peripapillary RNFL thickness 1.74 mm from the center of the disc was 132.7 +/- 14.4 micro m, and the average macular RNFL thickness was 44.8 +/- 14.8 micro m. The average macular retinal thickness was 173 +/- 28.5 micro m. The average peripapillary RNFL thickness in the four quadrants was as follows: superior 157.7 +/- 17.8 micro m, nasal 109.3 +/- 19.1 micro m, inferior 159.8 +/- 18.9 micro m, and temporal 102.5 +/- 19.0 micro m. There were no gender-related differences in macular or peripapillary RNFL thickness (P = 0.12 and P = 0.35, respectively). The average macular and peripapillary RNFL thickness was thinner in older Latinos than in younger Latinos (P = 0.04 and P = 0.0001, respectively). Regional and age-related differences in the peripapillary and macular RNFL thickness should be considered when diagnosing and monitoring individuals with diseases that affect the RNFL.