Myelinated Retinal Nerve Fibers Research Articles

Myelinated Retinal Nerve Fiber Progression in a 10-Year Follow-Up. The Beijing Eye Study 2001/2011

To assess the prevalence of myelinated retinal nerve fibers (MRNFs), the rate of their change in a 10-year follow-up, and associations with ocular and systematic parameters in a population-based cohort. Longitudinal population-based cohort study. The Beijing Eye study including 4,439 participants aged 40+ years in 2001 and was repeated in 2011, with 2,695 individuals (66.4% of the surviving) being re-examined in 2011. All participants underwent detailed physical and ocular examinations. MRNFs were diagnosed on fundus photographs and their change was assessed using a flicker method of fundus photographs. Out of 35 eyes (29 participants) with detected MRNFs at baseline (mean prevalence: 0.4% ± 0.26% per eye or 0.7% ± 0.41% per individual), 23 eyes from 20 individuals (17 [85%] participants with unilateral MRNFs) were re-examined in 2011. MRNF enlargement was detected in all 19 eyes (100%) with clear fundus photographs. The mean MRNF area increased from 4,233 ± 3,670 µm2 (range: 178-11,643 µm2) at baseline to 5,243 ± 4,092 µm2 (range: 196-13,297 µm2) at follow-up (P < .001), by 1,010 ± 1,026 µm2 (18-3,967 µm2) or by 47% ± 74% (9%-315%). A larger MRNF increase was associated with an MRNF location distant from the optic disc as compared to a juxtapapillary location (P=.001, standardized regression coefficient beta: -0.53), smaller MRNF area at baseline (P=.006, beta: -0.34), and higher serum concentration of low-density lipoproteins (LDL) (P < .001, beta: 0.57). MRNFs (mean prevalence per eye: 0.4%) showed, in association with higher LDL serum concentration and peripheral located MRNF, an enlargement during a 10-year follow-up, while in the same period no new MRNFs were detected in the total study cohort.

The long-term observation in Chinese children with monocular myelinated retinal nerve fibers, myopia and amblyopia.

BackgroundThe syndrome of monocular myelinated retinal nerve fibers (MRNF), myopia and amblyopia threatens visual development of infants and young children. The efficacy of part-time occlusion therapy remains controversial, and the long-term prognosis of the syndrome remains unclear.MethodsTen children (4.40±2.22 years, 4 boys and 6 girls) with monocular MRNF, myopia and amblyopia were recruited. Both the affected eyes (treatment group) and the fellow eyes (control group) underwent routine ophthalmic examinations, including AL, cycloplegic refraction, best-spectacles-corrected distance visual acuity (BSCDVA), cover test, simultaneous perception, corneal curvature, anterior segment and fundus examinations. Refractive error was corrected by either spectacles or rigid gas permeable (RGP) contact lenses. Part-time occlusion therapy was employed for amblyopia treatment. The retinal characteristics were examined only on the final visit with a Fourier-domain optical coherence tomography (FD-OCT). The speed of myopia progression and axial elongation were calculated. Statistical analysis was performed using SPSS 20 software. Cut-off P values were 0.05.ResultsOn the final visit, six children had normal simultaneous perception but three had strabismus. The mean AL and spherical equivalent (SE) values of the affected eyes were 28.05±1.59 mm and −12.60±4.20 D, respectively, while those of the fellow eyes were 23.67±1.13 mm and −0.66±1.99 D, respectively. AL and SE were significantly different over time and between groups (P<0.0001), but no time*group interaction effect (P>0.05) was observed. The differences in the corneal curvature, mean speed of myopia progression, axial elongation, foveal thickness and parafoveal thickness between the two groups were not significant (P>0.05). However, the perifoveal thickness in the affected eyes was significantly higher than that of the control eyes (P=0.047). In the treatment group, the occlusion dosage positively correlated with the final BSCDVA (R=0.764, P=0.016) but did not correlate with the speed of myopia progression or axial elongation (both P values >0.05).ConclusionsThe affected eyes have longer AL, severer myopia and thicker perifoveal retina when compared with the fellow eyes. Both the affected and the fellow eyes have similar speed of myopia progression as well as that of axial elongation.

Prevalence and Clinical Characteristics of Myelinated Retinal Nerve Fibres in a Chinese Teleophthalmology System

ABSTRACT Purpose: To investigate the prevalence and clinical characteristics of myelinated retinal nerve fibre (MRNF) in a large teleophthalmology system. Methods: All records between January 2015 and December 2015 from Daheng Prust teleophthalmology system were reviewed by 2 ophthalmologists independently. MRNF was classified into continuous group and discontinuous group according to the relationship between MRNF patches and optic disc. The number, total area and location of MRNF patches were analysed. Concomitant ocular diseases were documented. Results: Out of 51469 subjects, MRNF was detected in 304 eyes of 263 subjects with a prevalence rate of 0.51 ± 7.1% per subject and 0.30 ± 5.4% per eye. Among 304 eyes with MRNF, 239 (78.6%) eyes were in continuous group and 65 (21.4%) eyes were in discontinuous group. Single MRNF patch was found in 249 (81.9%) eyes and multiple MRNF patches were found in 55 (18.1%) eyes. MRNF of small size was found in 150 (49.3%) eyes. The ratios of multiple MRNF patches and small-sized MRNF in the continuous group were significantly higher than those in the discontinuous group (P = .014 and P < .001). In continuous group, the MRNF patches were located most frequently in the superior region (68.6%) of the optic disc; In discontinuous group, the MRNF patches were located most frequently in the inferotemporal region (38.5%) of the retina. Epiretinal membrane (12 eyes, 3.9%) was the most common concomitant ocular disease. Conclusion: MRNF is uncommon in China. MRNF usually presents unilaterally and as a single small whitish patch that is connected with optic disc.

Bilateral Macular Myelinated Retinal Nerve Fibers and Congenital Nystagmus

A systemically well 4-year-old boy was referred to our clinic for congenital nystagmus. Visual acuity was 20/200 in each eye after myopic correction (right eye –7.00+1.00×90; and left eye –7.75+1.00×100). He had horizontal, pendular nystagmus that dampened on convergence. There were symmetrical, concentric, grayish-white perifoveal elevations (Fig A-B). Full-field electroretinogram revealed attenuated cone pathway responses (Fig C). OCT demonstrated retinal nerve fiber layer hyperreflectivity and thickening (Fig D).

Unilateral Extensive Myelinated Retinal Nerve Fiber Layer in a Child

We are reporting a case of an incidental finding of an extensive Myelinated Retinal Nerve Fiber Layers (MRNFL) in a healthy 12-year-old Malay boy. The child did not complain of any blurring of vision until he accidentally closed his seeing eye. On examination, the right visual acuity was 6/6 while the left visual acuity was 6/150. There was no Relative Afferent Pupillary Defect (RAPD). The anterior segment was unremarkable. The fundus of the right eye was normal with a pink optic disc with CDR of 0.4, however, the left eye showed extensive MRNFL involving the whole fundus but sparing the macula. The subjective refraction of the right eye was Plano with 6/6 vision, while the left was –5.50/-1.50x50 with a vision of 6/150. Bjerrum of the right eye was normal but the left eye showed tunnel field at around 20 degrees with 2mm target size. His Humphrey Visual Field (HVF) 30-2, for the right eye, was normal with MD -0.90 while the left eye showed a generalized reduction of the field with MD of -20.23. Optical Coherence Tomography (OCT) of the right eye was normal while the affected eye showed thickening of the RNFL at the peripheral. The other layers of the retina and the foveal region of anatomy were somehow preserved. The axial length of the right eye was 24.10mm while the left eye was 28.06mm. MRNFL is a benign condition. It is commonly seen as a streak of whitish patch starting from the optic disc extending to the retina following the arcuate nerve fiber layer pattern, however, extensive myelinated retinal nerve fiber layer involving the whole retina was not very common and usually associated with amblyopia, axial myopia, and squint. Even though mostly benign and solitary, MNFL can be associated with other systemic condition, therefore, clinicians must rule out other systemic diseases.

Myelinated retinal nerve fiber and associated pathologies: high myopia, amblyopia, leukocoria and strabismus

Myelinated retinal nerve fiber and associated pathologies: high myopia, amblyopia, leukocoria and strabismus

CLINICAL FEATURES, IMAGING, AND NATURAL HISTORY OF MYELINATED RETINAL NERVE FIBER LAYER.

To evaluate the natural history of myelinated retinal nerve fiber layer (MRNFL) through clinical features and enhanced depth imaging optical coherence tomography. This is a retrospective, noncomparative, case series of patients who underwent thorough clinical examination to document associated ocular and systemic features. Enhanced depth imaging optical coherence tomography was performed when MRNFL was located posteriorly and accessible to imaging. Seventy-two eyes of 62 patients had a total of 86 MRNFL lesions. Enhanced depth imaging optical coherence tomography (n = 42 eyes) showed that all lesions originated in the nerve fiber layer with preservation of the vascular structures. Mean thickness by enhanced depth imaging optical coherence tomography was 255 μm (median, 182 μm; range, 61-717 μm). Natural history was obtainable in 58 lesions with a mean follow-up duration of 57 months (median, 37 months; range, 2-253 months) with no significant change overall in largest basal diameter (2.5 vs. 2.5 mm; P = 0.361) or thickness (255 vs. 240 μm; P = 0.053). However, evidence of lesion change included growth in base only (≥0.5 mm) (3 of 58; 5%), growth in base (≥0.5 mm) and thickness (≥50 μm) (3 of 58; 5%), and reduction in base (≥0.5 mm) after plaque radiotherapy for choroidal melanoma (3 of 58; 5%). In general, MRNFL is a rare, benign retinal finding with a potential for growth in 10% of cases. This supports previous histopathological reports that MRNFL represents accumulation of both myelin and oligodendrocytes and could be an oligodendrocytic choristoma.

Acquired and progressive myelinated retinal nerve fibers in neurofibromatosis type 1

Acquired myelinated retinal nerve fibers (MRNF) is rare. The reported cases occur after optic disk injuries. We describe a case of a patient with neurofibromatosis type 1 and bilateral optic pathway glioma, who after 3years' follow-up developed unilateral MRNF. Optical coherence tomography of the optic nerve disclosed progressive increased thickness and hyper-reflectivity of the peripapillary retinal nerve fiber layer associated with the myelinization process.Although the patient remains asymptomatic, myelinization continues to progress.

Characterization of ectopic myelinated nerve fibers in the retina of a cynomolgus monkey (Macaca fascicularis)

We report histopathology of retinal myelination discovered in a cynomolgus monkey. It consisted of a uniform population of spindle cells arranged in fascicles within the retina at the optic disk. The present case is remarkable in that there is a paucity of reports describing myelinated retinal nerve fibers in monkeys.

Unilateral Myelinated Retinal Nerve Fibers.

Unilateral Myelinated Retinal Nerve Fibers.

Myelinated Retinal Nerve Fiber Layer (RNFL): A Comprehensive Review.

Myelinated Retinal Nerve Fiber Layer (RNFL): A Comprehensive Review.

Unilateral Myelinated Retinal Nerve Fibers.

Unilateral Myelinated Retinal Nerve Fibers.

Régression des fibres nerveuses rétiniennes myélinisées dans un cas de glaucome primitif à angle ouvert

Myelinated retinal nerve fibers observed rarely on ocular fundus examination, usually adjacent to the optic disc, are known to be stable throughout life. However, the possibility of rarefaction, and even disappearance, of these myelinated fibers has been pointed out in very rare cases of ocular or neuro-ophthalmological pathologies. We report such a regression, identified after a six-year period, in one case of primary open-angle glaucoma.

PREVALENCE AND ASSOCIATIONS OF MYELINATED RETINAL NERVE FIBERS: Results From the Population-Based Gutenberg Health Study.

To determine the prevalence, ocular, and systemic associations of myelinated retinal nerve fibers (MRNF) in a Caucasian cohort. The Gutenberg Health Study (GHS) is a population-based, prospective cohort study encompassing 15,010 subjects in Germany. Gutenberg Health Study participants, aged 35 to 74 years, stratified for gender, decades of age, and residence were examined for ophthalmologic and systemic conditions. Optic disc centered and macular photographs were reviewed for the presence of MRNF. In 25,728 eyes of 12,906 participants (86.0% of the cohort), the prevalence of MRNF was 0.4%. In a binary logistic regression analysis, MRNF was positively associated with history of stroke (OR, 6.8; 95% CI, 2.9-16.1; P < 0.001). Myelinated retinal nerve fibers was not associated with age, sex, cardiovascular conditions other than stroke or ocular parameters, such as refraction, visual acuity, intraocular pressure, or central corneal thickness. This population-based study provides novel data on the prevalence of MRNF in Western Europe. We report a positive association between history of stroke and MRNF. It adds an additional retinal sign for stroke and calls for further studying of the behavior of oligodendrocytes within cerebrovascular diseases.

Unilateral myelinated retinal nerve fibers associated with ipsilateral myopia and amblyopia

The objective is to evaluate the clinical features of unilateral myelinated retinal nerve fibers (MRNF) associated with ipsilateral myopia and amblyopia. We retrospectively analyzed three patients with unilateral MRNF associated with ipsilateral myopia and amblyopia. The ages at presentation range from 4 to 10 years. Refractive error in affected eye ranged from S-6.25DC-2.00D toS-9.75DC-1.25D40. Anisometropia ranged from 6.75D to 10.50D. Best corrected visual acuity in affected eye ranged from 0.04to 0.2. Strabismus was documented in 2 of 3 patients. All patients underwent amblyopic treatment, which included prescription of full cycloplegic refraction and patching of the no amblyopic eye. However, all patients had a uniformly poor visual outcome. We should beware of the limited prognosis in patients with unilateral MRNF associated with ipsilateral myopia and amblyopia.

Microperimetry and spectral domain optical coherence tomography in myelinated retinal nerve fibers.

Microperimetry and spectral domain optical coherence tomography in myelinated retinal nerve fibers.

Myelinated Retinal Nerve Fibers in Children: OCT Imaging, Refractive Error and Vision

Purpose: To characterize peripapillary retinal nerve fiber layers (RNFL’s) and macular retinal structure in children with unilateral myelinated retinal nerve fibers (MRNFs). We also investigated the correlation between MRNF abnormalities and refractive error/visual acuity. Methods: Twelve children (7-13 years old) with MRNFs were included. Fourier domain optical coherence tomography was used to image both the peripapillary RNFL and the macular retinal structures in 6 patients. Using the instrument’s segmentation software, global RNFL thickness and central subfield thickness (CST) of the macula were analyzed. Planimetry was used to quantify the MRNF area observed on fundus photography. Visual acuity and cycloplegic refractive errors (spherical equivalent) were also recorded. Results from the MRNF-affected eye were compared with the fellow eye. Results: The global RNFL thickness of the eyes with MRNFs (152 ± 13.9 μm) was significantly higher than the fellow eyes (114.3 ± 15.2 μm) (P=0.003). The global RNFL thickness of the fellow eye was in normal range, and no significant differences were detected in macular CST between the eyes with MRNFs and fellow eyes (P=0.403). The MRNF area was significantly correlated with the spherical equivalent of the affected eye (P=0.002). In addition, the interocular difference of RNFL thickness between eyes was significantly correlated with anisometropia (P=0.03). Conclusions: Eyes with MRNFs show a significantly thicker global peripapillary RNFL trend as compared to the fellow eye, and the area of MRNFs is correlated with the development of myopia and anisometropia, but not correlated to visual acuity.

Swept source optical coherence tomography of a vitreal pocket entrapped in myelinated retinal nerve fibers

A 53-year-old women, 20/20 visual acuity in both eyes, showed after dilated fundus examination myelinated retinal nerve fibers (MRNF) on 360 around optic disk in left eye, sparing the macula (A). Swept source optical coherence tomography (SS-OCT) scanning line centered on the optic nerve head (B), showed two vitreous pockets (*) entrapped between highly hyperreflective MRNF and posterior hyaloid; posterior hyaloid appears thickened by hyperreflective tissue that can be interpreted as residual of innermost layer of myelin remained attached after posterior hyaloid separation.

Multimodal imaging of peripheral myelinated retinal nerve fiber layers without optic disk involvement

Multimodal imaging of peripheral myelinated retinal nerve fiber layers without optic disk involvement

Syndrome of myelinated retinal nerve fibres, myopia, amblyopia and strabismus in a Nigerian.

Myelinated retinal nerve fibres (MRNF) are rare congenital anomalies. They may present in a syndrome characterised by ipsilateral myelinated retinal nerve fibres, myopia and amblyopia. We report a case of this rare condition with unilateral extensive MRNF, axial myopia, amblyopia and strabismus in a Nigerian girl.