Myelinated Retinal Nerve Fibers Research Articles

Characteristics of the fundus and optical coherence tomography angiography metrics in myopic patients with myelinated retinal nerve fibers

AimsTo investigate the fundus characteristics and macular optical coherence tomography angiography (OCTA) metrics in patients with myelinated retinal nerve fibers (MRNF) and to identify the associations among myopic parameters, fundus metrics, and OCTA metrics.MethodsThe single-center case-control study included 15 patients with monocular MRNF and 15 patients without MRNF, matched for age, affected eyes’ spherical equivalent error (SER), and axial length (AL) between May 2021 and December 2021. Fundus features, including the entire MRNF area (Area1), the denser MRNF area (Area2), and the shortest distance from the fovea to the MRNF border (Df−m), along with ocular parameters, including SER, AL, best corrected visual acuity (BCVA), and OCTA metrics at the fovea, including choroidal (ChT) and retinal (ReT) thicknesses at the fovea, the foveal avascular zone area (FAZ), foveal avascular zone perimeter (FAZP), FAZ-circularity index (FAZ-CI), and foveal vessel density in a 300-µm wide region (FD-300), were assessed.ResultsThe SER, AL, and BCVA were significantly different, and the ChT was thinner in the affected eyes than in the contralateral eyes. Compared with matched eyes, affected eyes had reduced BCVA and thinner ReT. In the affected eyes, both Area1 and Area2 were negatively correlated with SER (r1 = -0.84, r2 = -0.65), △SER (r1 = -0.86, r2 = -0.61), ReT at the vertical superior 3 mm (VS) (r1 = -0.78, r2 = -0.67), and ChT_VS (r1 = -0.64, r2 = -0.62), and positively correlated with AL (r1 = 0.82, r2 = 0.52) and BCVA (r1 = 0.54, r2 = 0.59). Df−m was negatively correlated with BCVA (r = -0.57).ConclusionThe presence of MRNF affects BCVA and ReT at the fovea. The area of the MRNF, as well as the distance from the MRNF to the fovea, are closely associated with the affected eyes’ BCVA, SER, AL, and the degree of anisometropia.

First Application of Whole Genome Sequencing in Myelinated Retinal Nerve Fibers (MRNF)

First Application of Whole Genome Sequencing in Myelinated Retinal Nerve Fibers (MRNF)

Characteristics of myelinated retinal nerve fibres in associated straatsma syndrome.

To study cases diagnosed of myelinated retinal nerve fibres (MRNF) continuous with the optic disc and describe the plausible pathogenic mechanism for the ocular features in Straatsma syndrome. This retrospective observational study includes clinically diagnosed MRNF cases. MRNF, myopia, and amblyopia defined Straatsma syndrome. MRNF were classified into three types based on location: type 1 in the superior retina, type 2 in the superior and inferior retina, and type 3 in the inferior retina. MRNF size was measured on Optomap® (Optos, Daytona, UK) images and posterior staphyloma location was noted. Demographics and best-corrected refractive error in logMAR units was recorded. Descriptive statistics and Spearman's corelation test were used to analyse MRNF size's relationship to refractive error and logMAR visual acuity. The study included a total of 19 MRNF eyes from 18 patients. Seventeen (89%) eyes had Straatsma syndrome. Median age was 23.50 [range: 4-75] years. One (6%) patient exhibited bilateral presentation. The median logMAR visual acuity was 0.4 log units (interquartile range: 0.18-1.20) and mean refractive error was -7.21 ± 5.32. Type 2 MRNF (n = 14,74%) was the commonest. Average MRNF size was 34.37 ± 40.73 sq.mm. Posterior staphyloma was noted in 17 eyes, all in close MRNF association. Significant positive corelation was noted between logMAR visual acuity and MRNF size (r = 0.5, p = 0.028). Large size MRNF corelated with poor visual acuity in the study. The paper explains the possible pathogenetic mechanisms for the ocular findings seen in MRNF.

Reverse straatsma syndrome and lamellar cataract: a case report and review of the literature

Myelinated retinal nerve fiber (MRNF) is a developmental anomaly that is often detected during routine ophthalmological examination, but can be an ocular finding in a wide variety of diseases. An important example of this group is the Straatsma Syndrome. Straatsma Syndrome is an entity that presents with the triad of myopia, amblyopia, and MRNF. When this triad is accompanied by hyperopia instead of myopia, it is referred to as the Reverse Straatsma Syndrome. Here, we present a case of Reverse Straatsma Syndrome accompanied by lamellar congenital cataracts.

Unilateral Myelinated Retinal Nerve Fibers Associated with Ipsilateral Myopia, Amblyopia and Exotropia

This report describes a case of unilateral myelinated retinal nerve fibers associated with ipsilateral myopia, amblyopia and exotropia. A 3-year-old boy presented with the complaint of diminished vision in his right eye. Visual acuity testing with a picture at a distance of 2.5 m revealed 1.5 in the left eye, but right visual acuity was not available. Near visual acuity with dot cards was 0.2 in the right eye and 0.6 in the left eye. The refractive error was -7.25D and +1.50D in the right and left eyes, respectively. Fundus examination revealed extensive myelinated retinal nerve fibers in the right eye, but no abnormal findings in the left eye. The axial length was 24.10 mm and 22.90 mm in the right and left eyes, respectively. Cycloplegic retinoscopy revealed a refractive error of a −7.00D in the right eye and plane in the left eye. Glasses with full optical correction were prescribed, and the patient was evaluated one month later, presenting a best-corrected visual acuity of 0.6 in the right eye and 2.0 in the left eye with a picture at a distance of 2.5 m. Three months later, his visual acuity was 0.7 in the right eye. At this point, amblyopia treatment was started with two hours daily of left eye occlusion. One year following the initial presentation, his visual acuity improved 0.8 in the right eye. The type of fixation, the initial visual acuity, the high myopia and the high anisometropia indicated a most likely bad prognosis. However, the age of diagnosis and wearing status of glasses were advantage for treatment effect in this case. Even though this condition is associated with poor visual prognosis, intensive occlusion therapy should always be attempted, along with the prescription of a cycloplegic refraction, due to unexpected and variable responses to treatment.

Familial myelinated nerve fiber

Abstract We describe three cases of myelinated retinal nerve fibres, in a patient, her brother and mother, suggesting that an inherited defect may be responsible in certain cases.

Myelinated Retinal Nerve Fiber Layer in Idiopathic Intracranial Hypertension: A Rare and Challenging Scenario.

Myelinated Retinal Nerve Fiber Layer in Idiopathic Intracranial Hypertension: A Rare and Challenging Scenario.

Macular Imaging Characteristics in Children with Myelinated Retinal Nerve Fiber and High Myopia Syndrome.

To investigate the macular imaging features in patients with unilateral myelinated retinal nerve fiber (MRNF) and high myopia syndrome. Six patients with unilateral MRNF and high myopia syndrome and 13 myopic controls were enrolled in this study. Spectral domain (SD) optical coherence tomography (OCT), SD enhanced depth imaging OCT, and OCT angiography (OCTA) imaging results of MRNF-affected eyes were compared with the fellow eyes and myopic controls. All patients had abnormal foveal reflex and/or ectopia. No significant difference in retinal thickness parameters were noted between the groups. In OCT scans, posterior vitreous detachment (PVD) was observed in 4 out of the 6 MRNF-affected eyes. Regarding OCTA parameters, only a significant increase in acircularity index was noted in myelinated eyes (p=0.01). All patients demonstrated normal foveal contours, macular structure, and OCTA features except for a higher acircularity index. The incidence of PVD was notably increased in the myelinated eyes.

Myelinated retinal nerve fibers associated with retinal vascular abnormalities and retino-vitreal neovascularization complicated by recurrent vitreous hemorrhage (clinical case)

Myelinated retinal nerve fibres are a rare, benign and asymptomatic lesion that is detected incidentally at fundus examination. In some cases, they may be associated with various abnormalities of the eye or have a complicated course. The article presents a clinical case of myelinated retinal nerve fibers associated with retinal vascular abnormalities and retino-vitreal neovascularization complicated by recurrent vitreous hemorrhage.

Myelinated Retinal Nerve Fibers, a Complicating Factor in Amblyopia Rehabilitation?

Myelinated Retinal Nerve Fibers, a Complicating Factor in Amblyopia Rehabilitation?

Myelinated Retinal Nerve Fibers

We report a case of a 25-year-old-woman, with no pathological history. The patient presented to ophthalmology consultation for a routine eye examination.

Multimodal imaging in myelinated retinal nerve fiber layers

Multimodal imaging in myelinated retinal nerve fiber layers

Extensive myelinated retinal nerve fibres and bilateral foveal hypoplasia: A specific clinical entity.

Extensive myelinated retinal nerve fibres and bilateral foveal hypoplasia: A specific clinical entity.

Visual outcomes and retinal characteristics in children with myelinated retinal nerve fibers, myopia and amblyopia

Myelinated retinal nerve fibers are a rare congenital developmental anomaly, which may be associated with high myopia and resulting severe amblyopia in unilateral cases. Early detection, refractive correction, and amblyopia treatment can result in improvement of visual function in cases without optic nerve hypoplasia. Limited data regarding macular thickness and lamination are available in such children.

Swept-source optical coherence tomography of myelinated retinal nerve fiber layer.

Swept-source optical coherence tomography of myelinated retinal nerve fiber layer.

Myelinated Retinal Nerve Fiber Layer

The axons of the retinal ganglion cells compose the retinal nerve fiber layer, located in the inner (closest to the vitreous) retina. These axons coalesce at the optic disc and traverse the scleral canal to become the optic nerve. Posterior to the globe, the axons of the optic nerve become myelinated by supporting oligodendrocytes. Within the retina, however, myelination of these axons is present in only about 0.5% of autopsy eyes and has the appearance of a feathery, white opacity in the inner retina.

Hypermetropia, myelinated retinal nerve fiber and amblyopia: Reverse straatsma syndrome

Myelinated retinal nerve fibers (MRNF) are a common developmental anomaly. MRNF is commonly associated with myopia. The association of MRNF with myopia, amblyopia, and strabismus is well documented. The amblyopia may be refractory to treatment. We report a case of a child with MRNF and amblyopia in the more hyperopic eye, a case of reverse Straatsma syndrome.

Myelinated retinal nerve fiber layer: an extensive presentation.

Myelinated retinal nerve fiber layer is rare. It is estimated to occur in 0.5% to 1% of the population and is often detected on routine examination without symptoms. It consists of white or gray-white well-demarcated patches on the outermost surface of the retina that obscure the underlying retinal vessels. It can be associated with axial myopia, amblyopia, and strabismus. A 12-year-old girl with normal development presented with ocular deviation of the right eye. There was no past medical or ocular history. Automatic refraction found in the right eye -9 DP and -1 DP in the left eye. The best Visual acuity was 20/600 in the right eye and 20/20 in the left one. Slit lamp examination of the right eye (A) revealed two vast whitish zones extending from the papilla towards the temporal sector sparing the posterior pole. These lesions covered the temporal vessels with fuzzy and scalloped boundaries. Fundus examination of the left eye was without abnormalities (B). Scan of Optical coherence tomography showed isolated hyper reflectivity of the fiber optic layer, an abnormality of the vitreoretinal interface with posterior shadow cone effect (C).

Straatsma Syndrome: Should Visual Prognostic Factors Be Taken into Account? A Case Report

Straatsma syndrome is the triad of myelinated retinal nerve fibers, myopia, and amblyopia and may be associated with strabismus, nystagmus, hypoplastic optic nerve, and heterochromia iridum. The degree of anisometropia, presence of strabismus, extent of myelination, and macular involvement have been reported to be associated with poor visual acuity after occlusion therapy for amblyopia in this syndrome. Here we present two cases of Straatsma syndrome with different responses to occlusion therapy and discuss their treatment responses according to prognostic factors for post-occlusion visual acuity.

Progressive Myelinated Retinal Nerve Fibers in Children With Craniosynostosis.

The authors found the changes of myelinated retinal nerve fibers in one pair of identical twins with nonsyndromic craniosynostosis and two patients with Crouzon syndrome, who were at risk for impaired lamina cribrosa barrier function. This is the first report of progressive and presumed acquired myelinated retinal nerve fibers in craniosynostosis. [J Pediatr Ophthalmol Strabismus. 2021;58(6):e40-e43.].