Temporal Disc Margin Research Articles

Case report: what gives the myopic tilted disc an oval appearance?

BackgroundMyopic tilted disc, observed as an oval disc, has been alleged to be a funduscopic en-face manifestation of excessive optic nerve head (ONH) sloping or tilting. Here, we report the case of a myopic child showing a developing oval disc in fundus photos during axial elongation, but without progressive tilting in spectral-domain optical coherence tomography (SD-OCT) images.Case presentationBy merging B-scan SD-OCT images of the ONH and macula, the curvature of the posterior pole, including both the fovea and ONH, was reconstructed and compared before and after 2 years of axial elongation. Despite the marked increase of disc ovality, the posterior polar curvature was rarely changed. The preponderance of optic disc change was induced by the shift of the temporal disc margin in the nasal direction. This shifting alone imitated an increase of tilt angle but one that was still far smaller than the required degree of tilt for ONH-tilt-based disc ovality. To clarify, we calculated the required extent of axial elongation to obtain a substantial degree of ONH tilt when considering the adjacency of the fovea and the ONH. Without a focal increase of posterior polar curvature, which is to say posterior staphyloma, such change is not possible until the axial length increases extraordinarily.ConclusionThe most prominent change in the development of myopic tilted disc, which change gives it an oval appearance and imitates a tilt when measured, is actually not a tilt but rather a shift of the temporal disc margin.

Optic Disc Margin Anatomic Features in Myopic Eyes with Glaucoma with Spectral-Domain OCT

To investigate optic disc margin anatomic features in myopic eyes with open-angle glaucoma (OAG) using spectral-domain (SD) OCT. Cross-sectional study. Two hundred four eyes of 102 participants with OAG and 106 eyes of 53 participants without glaucoma with axial length of 24 mm or more. Radial SD OCT B-scans centered on the optic discs were acquired in each eye, and the SD OCT data were colocalized with the optic disc stereophotographs. Optic disc margin anatomic features were evaluated as (1) SD OCT structure coinciding with the disc margin identified in the stereophotograph, (2) border tissue configuration, and (3) presence of Bruch's membrane overhang, and their frequency was computed in each clock-hour position. Further, paired eyes of myopic participants with OAG were divided into eyes with better or worse visual field defect (VFD), according to the mean deviation of the Humphrey visual field test, and associated factors were compared. Spectral-domain OCT structures coinciding with the visible optic disc margin in stereophotographs. In myopic eyes with OAG, mean axial length was 25.96±1.07 mm and mean deviation was -8.87±7.78 dB. In approximately 90% of the participants, anterior scleral opening (ASO) coincided with the temporal disc margin and Bruch's membrane opening (BMO) with the nasal disc margin. Border tissue configuration was externally oblique in the temporal region and internally oblique in the nasal region of the optic disc. Bruch's membrane overhang was observed in a relatively small percentage of eyes. The same pattern of disc margin anatomic features was observed in the myopic eyes without glaucoma. The myopic optic disc was shaped by the temporal shifting of the BMO from the ASO, and the extent of shifting was expressed as the width of γ zone parapapillary atrophy (PPA). The greater γ zone PPA width was associated significantly with the worse VFD between paired eyes. The myopic eyes with OAG exhibited characteristic optic disc margin anatomic features that was considered to be derived from myopic deformation of the eye. The greater γ zone PPA width may increase susceptibility to the glaucomatous stress.

Early Spontaneous Reduction of Subsensory Fluid in A Case of Optic Disc Pit: A Rare Entity

To report a case of spontaneous resolution of a serous macular detachment associated with an optic disc pit, leading to significant visual improvement. A 17 years old male presented to the outpatient department with chief complaints of blurring of vision in the left eye for 13 days, with some improvement in last 3 days. The patient had consulted elsewhere 10 days back and was noted to have a visual acuity of 6/60 in the left eye and was diagnosed to have an Optic disc pit with serous retinal detachment involving the macula. He was advised pars plana vitrectomy with gas tamponade but he preferred to wait for some time. The patient presented to us with improvement of the visual acuity to 6/9 in the left eye. Detailed fundus examination showed a large disc with a pit at the temporal disc margin with serous detachment seen temporal to the fovea. The patient was advised against any intervention and asked for regular follow up. We report a exhibited spontaneous regression of serous macular detachment in a case of optic disc pit within 13 days with significant improvement in visual acuity in a 17 year old patient.

Posterior Vitreous Structures Evaluated by Swept-source Optical Coherence Tomography with En Face Imaging.

PurposeTo evaluate posterior vitreous structures using swept-source (SS) optical coherence tomography (OCT) with en face imaging.MethodsWe retrospectively reviewed OCT images of healthy individuals who did not have intra-ocular disease. We obtained high-definition horizontal and vertical line scans crossing the fovea and 3D scans using SS-OCT, with the 3D scan centered between the fovea and the optic-nerve head. An enhanced vitreous visualization function was used to highlight vitreous structures. En face mode was used to measure the area of Martegiani (AM) and bursa premacularis (BP). We performed all measurements using a built-in function of the viewing software.ResultsWe enrolled 24 eyes from 12 healthy individuals. The mean patient age was 28.7 ± 4.6 years (range, 24 to 39 years). The mean AM and BP areas were 5.73 ± 0.88 and 18.76 ± 6.95 mm2, respectively. In en face imaging, AM shape was most frequently a vertical oval (18 / 22, 81.8%), while the predominant BP shape was round (16 / 20, 80.0%). AM was in contact with the optic disc, either at the temporal-disc margin (13 eyes, 59.1%) or the nasal optic-disc margin (9 eyes, 40.9%).ConclusionsPosterior vitreous structures, such as AM and BP, were readily visualized using en face imaging with SS-OCT. Investigating normal vitreous configuration might help in understanding changes in vitreous structures associated with retinal pathology.

Relationship between disc margin to fovea distance and central visual field defect in normal tension glaucoma

To investigate the relationship between ocular geometric factors, including temporal disc margin to fovea distance (DFD) measured by optic disc stereophotography (ODP) and central visual field (VF) defect, in normal-tension glaucoma (NTG) patients. This retrospective, single-center, cross-sectional study included 88 eyes of 88 NTG patients with mild VF defects (MD > -6.0dB). NTG patients were divided into two groups according to VF tests: central VF-invading and central VF-sparing groups. Optic nerve head (ONH) parameters including disc dimensions, peripapillary atrophy (PPA), and DFD were obtained by ODP, and retinal nerve fiber layer (RNFL) thickness was measured by Stratus optical coherence tomography (OCT). In the invading group, DFD was shorter (3.642 ± 0.401mm) than in the sparing group (3.877 ± 0.278mm; p = 0.002). The sparing group had more vertically oval ONH (p = 0.023) and wider temporal PPA width (p = 0.031). The RNFL thickness in the invading group was thinner in the temporal and inferior quadrants, but thicker in the superior quadrant than that of the sparing group. In a multiple linear regression analysis, DFD was the only geometric factor associated with degree of central VF involvement (p = 0.002). DFD was positively correlated with temporal RNFL thickness in the sparing group (r = 0.484, p < 0.001) but not in the invading group (r = -0.080, p = 0.631). Eyes with a shorter DFD should be monitored carefully because central VF involvement appears to be related to shorter DFD in NTG patients with mild VF defects.

Differentiation of Parapapillary Atrophy Using Spectral-Domain Optical Coherence Tomography

To develop a classification of parapapillary atrophy (PPA) based on its relationship with the location of Bruch's membrane (BM) termination in primary open-angle glaucoma (POAG) patients. Cross-sectional observational study. This study analyzed 161 eyes from 161 POAG patients who had temporal β-zone PPA, the width of which was more than 200 μm on at least 1 horizontal scan image obtained by spectral-domain optical coherence tomography within the mid horizontal one third of the optic nerve. Based on the extent of BM within the PPA area, eyes were categorized as group A (intact BM; 76 eyes), group B (discontinuous BM; 65 eyes), and group C (lacking BM; 20 eyes). Differences in the demographic, clinical, and ocular characteristics were compared using analysis of variance and chi-square tests among the 3 groups. The distance from the temporal optic disc margin to the temporal margin of the β-zone PPA (PPA width) and to the edge of the BM (width of PPA without BM [PPA-BM]) were measured on 3 horizontal scans within the mid horizontal one third of the optic nerve, and the averages of the measured values were analyzed. The configuration of the border tissue of Elschnig at the temporal disc margin was assessed. Factors and configuration of the border tissue of Elschnig associated with each PPA type. The mean age of group A was significantly higher than that of groups of B and C (P<0.001). The mean axial length was greatest in group C (group C>group B>group A; P<0.001). In group A, the border tissue mainly had a nonoblique configuration (49/76 eyes; 64.5%), whereas most of the eyes in group B (59/65 eyes; 90.8%) and all eyes in group C (20 eyes) it had an externally oblique configuration (P<0.001). A longer axial length was correlated significantly with a larger PPA-BM width (r = 0.478; P<0.001). A morphologic classification of PPA, which may reflect differing pathogenesis among the groups, is proposed. Parapapillary atrophy with intact BM may be an age-related atrophic change, whereas PPA lacking BM may result from scleral stretching associated with elongation of the globe. Proprietary or commercial disclosure may be found after the references.

In-Vivo Microstructural Anatomy of β-Zone Parapapillary Atrophy in Glaucoma

To assess the microstructural anatomy of clinical β-zone parapapillary atrophy (βPPA) by using Fourier-domain optical coherence tomography (FD-OCT). Color photographs and horizontal cross-sectional FD-OCT images of the optic disc and parapapillary retina were obtained in 24 eyes (24 patients with glaucoma or suspected glaucoma) with βPPA. The distances between the temporal disc margin and parapapillary landmarks (clinical βPPA margin and the edges of the retinal pigment epithelium [RPE], Bruch's membrane [BM], and the photoreceptor inner/outer segment [IS/OS] junction) were measured in 5 equally spaced horizontal meridians (total, 120 meridians). The mean age was 56 ± 13 (SD) years. In the five meridians, the mean distances from the temporal disc margin to the temporal βPPA margin and the edges of RPE, BM, and the IS/OS junction were 388 ± 173, 371 ± 174, 214 ± 204, and 502 ± 167 μm, respectively. The RPE edge corresponded to the βPPA margin in 78 (65%) of 120 meridians and ended within the βPPA in 42 (35%) of 120 meridians. The BM edge corresponded to the RPE edge in 13 (11%) of 120 meridians and was closer to the disc in 107 (89%) of 120 meridians. The disc margin corresponded to the BM edge in 20 (17%) of 120 meridians and to the edge of the border tissue of Elschnig in 100 (83%) of 120 meridians. The IS/OS junction edge was farther from the disc than the temporal βPPA margin was in all 24 eyes. The βPPA was not completely denuded of RPE, and there was a crescent-shaped area of photoreceptor degeneration or atrophy peripheral to the βPPA. The termination of the border tissue of Elschnig constituted the temporal disc margin in most eyes with βPPA.

Peripapillary Schisis with Serous Detachment in Advanced Glaucoma

To describe features associated with the development and resolution of peripapillary retinoschisis with an underlying serous detachment in a patient with primary open angle glaucoma. This presentation occurred in the absence of an observed optic nerve coloboma, congenital, or acquired optic nerve head pit. A patient with advanced glaucomatous optic nerve cupping developed a temporally localized peripapillary serous detachment in the right eye which spontaneously resolved. Optical coherence tomography demonstrated an area of retinoschisis with underlying serous detachment contiguous with the temporal disc margin. Although fluorescein angiography was not performed and the presence of a peripapillary subretinal neovascular membrane could not be ruled out, an atypical coloboma, optic nerve head pit, or peripapillary subretinal neovascular membrane was not observed during biomicroscopy or scanning laser ophthalmoscopy. The retinoschisis and detachment resolved without intervention. Peripapillary retinoschisis with an underlying serous detachment may develop in subjects with advanced glaucoma. Although the occurrence of the findings in this case may be unrelated to glaucomatous optic neuropathy, the likelihood that a pathogenic mechanism linked to advanced glaucoma may be responsible for the development of peripapillary schisis and serous detachment should alternatively be taken into consideration. This case documents its spontaneous resolution without intervention.

HRT-3 Moorfields reference plane: effect on rim area repeatability and identification of progression

Aims:To assess the effect of the Moorfields Reference Plane on Heidelberg Retina Tomograph (HRT) rim area repeatability and its effect on progression rates using an event analysis.Methods:The HRT reference plane...

The Prevalence of Optic Disc Pits and Their Relationship to Glaucoma

To determine prevalence and associations of pits of the optic disc in an older population and assess their relationship to open-angle glaucoma. Population-based cross-sectional study. The Blue Mountains Eye Study examined 3654 persons (82.4% of permanent residents) aged over 48 years. Stereo-optic disc photographs were graded in a masked fashion. Nine pits were found in 7 persons, a population prevalence of 0.19%. Three morphologic subtypes were found. Four peripheral pits were found at the inferior pole. Four central pits were located adjacent to the main vessel trunk. One pit was on the temporal disc margin. Pit prevalence increased with age (beta=0.0879, P=0.0099). It was strongly associated with high-pressure open-angle glaucoma [odds ratio (OR) 29, 95% confidence interval (95CI) 7-127], beta-peripapillary atrophy (OR 7.5, 95CI 2-32), and optic disc hemorrhage (OR 42, 95CI 9-183) after adjusting for age and sex. All peripheral pits were associated with paracentral visual field loss. The classically described temporal optic disc pit was the rarest morphologic subtype found in this older population. Optic disc pits were primarily associated with glaucoma and the related signs of optic disc hemorrhage and beta-peripapillary atrophy. The previously reported optic disc pit association with low-tension glaucoma may represent acquisition bias.