Foveal Morphology Research Articles

Foveal regeneration after resolution of cystoid macular edema without and with internal limiting membrane detachment: presumed role of glial cells for foveal structure stabilization.

To document with spectral-domain optical coherence tomography the morphological regeneration of the fovea after resolution of cystoid macular edema (CME) without and with internal limiting membrane (ILM) detachment and to discuss the presumed role of the glial scaffold for foveal structure stabilization. A retrospective case series of 38 eyes of 35 patients is described. Of these, 17 eyes of 16 patients displayed foveal regeneration after resolution of CME, and 6 eyes of 6 patients displayed CME with ILM detachment. Eleven eyes of 9 patients displayed other kinds of foveal and retinal disorders associated with ILM detachment. The pattern of edematous cyst distribution, with or without a large cyst in the foveola and preferred location of cysts in the inner nuclear layer or Henle fiber layer (HFL), may vary between different eyes with CME or in one eye during different CME episodes. Large cysts in the foveola may be associated with a tractional elevation of the inner foveal layers and the formation of a foveoschisis in the HFL. Edematous cysts are usually not formed in the ganglion cell layer. Eyes with CME and ILM detachment display a schisis between the detached ILM and nerve fiber layer (NFL) which is traversed by Müller cell trunks. ILM detachment was also found in single eyes with myopic traction maculopathy, macular pucker, full-thickness macular holes, outer lamellar holes, and glaucomatous parapapillary retinoschisis, and in 3 eyes with Müller cell sheen dystrophy (MCSD). As observed in eyes with MCSD, cellophane maculopathy, and macular pucker, respectively, fundus light reflections can be caused by different highly reflective membranes or layers: the thickened and tightened ILM which may or may not be detached from the NFL, the NFL, or idiopathic epiretinal membranes. In eyes with short single or multiple CME episodes, the central fovea regenerated either completely, which included the disappearance of irregularities of the photoreceptor layer lines and the reformation of a fovea externa, or with remaining irregularities of the photoreceptor layer lines. The examples of a complete regeneration of the foveal morphology after transient CME show that the fovea may withstand even large tractional deformations and has a conspicuous capacity of structural regeneration as long as no cell degeneration occurs. It is suggested that the regenerative capacity depends on the integrity of the threedimensional glial scaffold for foveal structure stabilization composed of Müller cell and astrocyte processes. The glial scaffold may also maintain the retinal structure after loss of most retinal neurons as in late-stage MCSD.

Foveal Pit Morphology Characterization: A Quantitative Analysis of the Key Methodological Steps.

Disentangling the cellular anatomy that gives rise to human visual perception is one of the main challenges of ophthalmology. Of particular interest is the foveal pit, a concave depression located at the center of the retina that captures light from the gaze center. In recent years, there has been a growing interest in studying the morphology of the foveal pit by extracting geometrical features from optical coherence tomography (OCT) images. Despite this, research has devoted little attention to comparing existing approaches for two key methodological steps: the location of the foveal center and the mathematical modelling of the foveal pit. Building upon a dataset of 185 healthy subjects imaged twice, in the present paper the image alignment accuracy of four different foveal center location methods is studied in the first place. Secondly, state-of-the-art foveal pit mathematical models are compared in terms of fitting error, repeatability, and bias. The results indicate the importance of using a robust foveal center location method to align images. Moreover, we show that foveal pit models can improve the agreement between different acquisition protocols. Nevertheless, they can also introduce important biases in the parameter estimates that should be considered.

Optical coherence tomography angiography in preterm-born children with retinopathy of prematurity.

To describe the foveal avascular zone (FAZ) and vessel density (VD) in the superficial and deep capillary plexus in children with a history of prematurity on optical coherence tomography angiography (OCTA) and their correlation with gestational age (GA) and birth weight (BW). We enrolled 81 preterm- and eight term-born children in this prospective observational study. The Optovue RTVue AVANTI (Optovue Inc., Fremont, CA) was used to procure the OCTA images. The 3 × 3 mm scan protocol centered on the fovea and the central 1 mm of the grid along with the FAZ of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) was acquired. The mean SCP-VD was comparable between the preterms and term controls (p = 0.315) in the central fovea (1-mm grid). However, the SCP-VD of the 3-mm grid was lower in the preterms born without ROP, with type 1 ROP, and with type 2 ROP (47.61, 47.90, and 48.82 respectively) compared to that in the term group (51.38; p = 0.031). The FAZ in the SCP (p = 0.003) and DCP (p = 0.003) was significantly smaller in the preterms compared to that in the controls. Based on the GA sub-analysis, the FAZ was significantly smaller in the SCP and DCP of preterms born < 31 weeks and > 31 weeks GA (p < 0.000, p < 0.035, respectively). Based on the BW, the difference between the FAZ in the SCP (p = 0.002) and DCP (p = 0.003) was significant. There was no association between the visual acuity and FAZ. Optical coherence tomography angiography findings in this study show an altered foveal morphology and vascularity in preterms with and without ROP.

Determinants of vitreomacular traction width: associations with foveal floor width and vitreoretinal interface changes.

To investigate the relationship between vitreomacular traction (VMT) width, foveal floor width (FFW) and other anatomical characteristics between eyes of patients with VMT. Retrospective observational study of unilateral and bilateral VMT cases from two specialist ophthalmic centres in the United Kingdom (UK) between 2016 and 2018. For unilateral VMT cases: VMT width in the affected eye and FFW in the non-affected fellow eye were measured. In bilateral VMT cases: VMT width in both eyes was measured. In all cases, the presence of any associated inner or outer retinal, and vitreoretinal interface (VRI) changes, including epiretinal membrane, was also documented. 88 patients fulfilled the study criteria: 57 having unilateral and 31 bilateral VMT. For unilateral VMT cases, log (VMT) width was significantly correlated with FFW (r=0.347, p=0.008). Using stepwise linear regression, FFW (p=0.004) and VRI changes (p=0.03) were both significantly associated with VMT width with a R2 of 0.21. In bilateral VMT cases, there was strong positive correlation between log (VMT) width (r=0.88, p<0.001), and the presence of any VRI (r=0.90, p<0.001) or outer retinal changes (r=0.50, p<0.001) between the two eyes. These findings suggest that individual variations in foveal morphology as measured by the FFW, along with the presence of vitreoretinal interface changes, are associated with the extent of VMT width. VMT width, VRI and outer retinal changes were also highly correlated between eyes in bilateral VMT, suggesting that individual patient factors, which may be genetic or acquired, determine their presence and extent.

Relation of anatomy with function following the surgical treatment of idiopathic epiretinal membrane: a multicenter retrospective study.

To investigate the prognostic factors associated with functional and anatomical outcomes and to assess the longitudinal course of visual acuity and retinal morphology after vitreoretinal surgery for idiopathic epiretinal membrane (ERM). This multicenter, retrospective study included a total of 634 eyes who underwent surgery for idiopathic ERM in 22 academic centers nationwide in Turkey. Data on best-corrected visual acuity (BCVA) and optical coherence tomography features (central foveal thickness (CFT), ERM and foveal contour morphology, ellipsoid zone (EZ) integrity) were collected and compared at baseline, 6-month, 12-month, and 24-month follow-ups. Prognostic factors for functional (having ≥ 20/25 Snellen BCVA) and anatomical (having normal/shallow foveal contour) recoveries after surgery were investigated by means of multivariate regression analyses. A cutoff value of preoperative BCVA optimizing functional recovery was calculated using receiver operating characteristic curve analysis. At a median follow-up of 24months, 37.4% of the eyes achieved ≥ 20/25 BCVA and 54% regained normal or shallow foveal contour. Functional recovery was more likely in eyes with better baseline BCVA and intact EZ (R2 = 0.356, p < 0.001). The cutoff baseline BCVA value for good visual prognosis was 0.35 logarithm of the minimum angle of resolution (Snellen 20/44) (sensitivity 60%, specificity 85%, p < 0.001). Anatomical recovery was negatively associated with advanced age, higher baseline CFT, foveal herniation-type ERM morphology, and internal limiting membrane (ILM) peeling (R2 = 0.225, p < 0.001). The negative effect of ILM peeling on anatomical recovery was not significant after the first postoperative year (p = 0.05). Mean BCVA values and foveal morphology progressively improved at each visit. Cases with convex baseline foveal contour continued to change towards normal foveal depression over 24months of follow-up, which took longer than the eyes with shallow/flat contoured cases. One-third of eyes with severe baseline EZ defects showed recovery at follow-up and achieved significantly greater visual acuity gains than the remaining eyes with persistent defects (p < 0.001). Functional and anatomical restoration of the eyes appears to be a slow process after ERM surgery. This process may take much longer in eyes with worse foveal morphology at baseline. Although photoreceptor disruption may be reversible in some eyes, full functional recovery is unlikely when it persists.

Myopia induces meridional growth asymmetry of the retina: a pilot study using wide-field swept-source OCT

Myopic axial eye growth has mechanical implications on ocular structures, such as the retinal and foveal shape integrity or choroidal thickness. The current study investigated myopia-related changes of retinal radius of curvature, foveal width, depth, slope and choroidal thickness. Wide-field swept-source OCT line and volume scans were performed on 40 young adult participants in horizontal and vertical directions. OCT scans were corrected for their scan display distortions before automated extraction of retinal and foveal shape parameters. All findings were correlated to refractive error and axial length. The horizontal retinal radius of curvature and the directional ratio between horizontal and vertical retinal shape correlated significantly with axial length (rho =+0.53, p<0.001 and rho =+0.35, p<0.05). Vertical retinal shape and foveal pit parameters neither showed any significant correlations with axial length nor refractive error (all p> 0.05). Choroidal thickness correlated significantly with refractive error in all analyzed regions (rho +0.39,mathrm{to},+0.52), but less with axial length (rho -0.18 to − 0.37). Horizontal retinal shape and choroidal thickness, but not foveal pit morphology, were altered by myopic eye growth. Asymmetries in horizontal versus vertical retinal shape with increasing myopia were detected. These parameters could act as promising biomarkers for myopia and its associated complications.

Interocular asymmetry of foveal avascular zone morphology and parafoveal capillary density in sickle cell retinopathy.

ObjectivesTo examine interocular asymmetry of foveal avascular zone (FAZ) and parafoveal capillary density metrics in sickle cell retinopathy (SCR) using optical coherence tomography angiography (OCT-A).MethodsThis cross-sectional, retrospective study evaluated SCR patients and unaffected controls who underwent 3x3mm macular OCT-A imaging using a spectral domain-OCT system. FAZ (area, perimeter, and acircularity index) and parafoveal capillary density metrics were computed for both eyes of each participant. In unaffected controls, interocular difference in FAZ and parafoveal capillary density metrics were evaluated using Bland-Altman plots. SCR patients with interocular difference outside the upper 97.5% and lower 2.5% limits of agreement from controls were defined as having interocular asymmetry. Area under receiver operating characteristic curve (AROC) was also performed to determine the ability of the absolute interocular difference to differentiate between subjects with SCR—including non-proliferative SCR (NP-SCR) and proliferative SCR (P-SCR)–and unaffected controls.ResultsThirty-one patients with SCR (21 NP-SCR and 10 P-SCR) and 14 race-matched and age-matched controls were included for analysis. Interocular asymmetry was seen for all FAZ and parafoveal capillary density metrics in NP-SCR and P-SCR subjects. SCR subjects showed greater disease severity in the left-eye for FAZ and parafoveal capillary density metrics.ConclusionsNP-SCR and P-SCR patients demonstrated quantifiable interocular asymmetry in FAZ and parafoveal capillary density metrics compared to unaffected subjects, with left-eye predominance in disease severity.

Foveal pit morphological changes in asymptomatic carriers of the G11778A mutation with Leber's hereditary optic neuropathy.

To investigate the foveal pit morphology changes in unaffected carriers and affected Leber's hereditary optic neuropathy (LHON) patients with the G11778A mutation from one family. This study was a prospective cross-sectional study. Both eyes from 16 family members (age from 9 to 47y) with the G11778A mutation were analyzed and compared with 1 eye from 20 normal control subjects. Eleven family members with the G11778A mutation but without optic neuropathy were classified as unaffected carriers (n=22 eyes). Five family members (n=10 eyes) expressed the LHON phenotype and were classified as affected patients. Retinal images of all the subjects were taken by optical coherence tomography (OCT), and an automatic algorithm was used to segment the retina to eight layers. Horizontal and vertical OCT images centered on the fovea were used to measure intra-retinal layer thicknesses and foveal morphometry. Thicker foveal thickness, thinner foveal pit depth, and flatter foveal slopes were observed in unaffected carriers and affected LHON patients (all P<0.001). Further, the slopes of all four sectors in the LHON were flatter than those in the unaffected carriers (all P<0.001). Compared with the control group, affected LHON patients had a thinner retinal nerve fiber layer (RNFL), ganglion cell layer and inner plexiform layer (GCL+IPL), and total retina (all P<0.01). The retinal nerve fiber layer (RNFL) of affected patients was 38.0% thinner than that of controls while the GCL+IPL was 40.1% thinner. The foveal pit morphology shows changes in both unaffected carriers and affects patients. RNFL and GCL+IPL are thinner in affected LHON patients but not in unaffected carriers.

Comparison of the Morphology of the Foveal Pit Between African and Caucasian Populations.

PurposeThe purpose of this study was to characterize foveal pit morphology in an African (Ghanaian) population, to compare it to that of a Caucasian group and to determine if it varied with age in the two populations.MethodsThe depth, diameter, slope, and volume of the foveal pit were interpolated from optical coherence tomography volume scans recorded in 84 Ghanaian and 37 Caucasian individuals. Their association with age, sex, and ethnicity was investigated using multilevel regression models.ResultsThe foveal pit differed significantly in width, slope, and volume between Ghanaian men and women (P < 0.001), but only in width and volume between Caucasian men and women (P < 0.01). In Ghanaians, age was associated with a narrowing of the foveal depression and a reduction of its volume. Overall, these changes were more pronounced in women as compared to men and were largely absent from the Caucasian group. When controlled for age, the foveal pit of Ghanaians was significantly wider and larger in volume as compared to the Caucasian group (P < 0.001).ConclusionsThe morphology of the foveal pit differs between African and Caucasian individuals. These anatomic differences should be considered when examining differences in prevalence and clinical features of vitreoretinal disorders involving the fovea between the two populations.Translational RelevanceDifferences in retinal anatomy may partly explain variations in the prevalence and clinical features of retinal diseases between Africans and Caucasians. Such differences should be adequately considered in diagnoses and monitoring of ocular diseases in patients with African ancestry.

Different modes of foveal regeneration after closure of full-thickness macular holes by (re)vitrectomy and autologous platelet concentrate.

To describe using spectral-domain optical coherence tomography the regeneration of the foveal morphology after pars plana (re)vitrectomy surgery and gas tamponade combined with injection of autologous platelet concentrate to treat full-thickness macular holes, and to describe different anatomical outcome. A retrospective case series of 8 eyes of 8 patients was described. In all cases investigated, the platelet-assisted closure of macular holes was associated with a rapid resolution of cystic cavities in the foveal walls. In two patients, there was a regular regeneration of the foveal morphology after hole closure; the regenerated central fovea had a regular structure with a foveola and photoreceptors. In three other patients, there was an irregular regeneration of the fovea; a foveola was not formed, photoreceptor cells were absent from the foveal center, and the center was composed of Müller and retinal pigment epithelial (RPE) cells. The foveal regeneration after hole closure may proceed with or without a temporary detachment of the foveal center from the RPE, and with or without a direct contact between the central outer nuclear layer (ONL) and the RPE. Contacts between the ONL and RPE were observed only in patients with an irregular foveal regeneration after hole closure. The data show that there are different modes of foveal regeneration after closure of macular holes with (re)vitrectomy and platelet concentrate. It is suggested that the regular regeneration of the foveal morphology proceeds by Müller cell-mediated tissue movements without cell proliferation, whereas the irregular foveal regeneration proceeds in part by proliferation of Müller and RPE cells.

FOVEAL SPARING INTERNAL LIMITING MEMBRANE PEELING FOR IDIOPATHIC MACULAR HOLES: EFFECTS ON ANATOMICAL RESTORATION OF THE FOVEA AND VISUAL FUNCTION.

Muller cells seem to be important in maintaining foveal morphology through connections between their foot processes and the internal limiting membrane (ILM). Internal limiting membrane peeling causes Muller cell trauma. We hypothesized that leaving a rim of unpeeled ILM around idiopathic macular holes undergoing vitrectomy surgery would improve postoperative foveal morphology and vision. Prospective pilot study of fovea-sparing ILM peeling in a consecutive cohort of patients with macular holes over a 12-month period. Spectral-domain optical coherence tomography and Early Treatment Diabetic Retinopathy Study letters best-corrected visual acuity were assessed preoperatively and postoperatively, and foveal morphology and metamorphopsia postoperatively. The foveal sparing group was compared with a second consecutive cohort who received standard ILM peeling (control group). Thirty-four eyes of 34 patients were included in each group. Groups showed no significant preoperative differences. 34/34 holes were successfully closed with surgery in the foveal sparing group and 32/34 in the control group. The foveal sparing group showed better postoperative best-corrected visual acuity (67.7 vs. 63.8, P = 0.003) and best-corrected visual acuity improvement (25.1 vs. 20.2, P = 0.03). The foveal sparing group demonstrated thicker minimum foveal thickness (211 vs. 173 μm, P = 0.002) and less steep foveal depression (158 vs. 149, P = 0.002). Preserving nonpeeled ILM around macular holes resulted in a high closure rate, improved foveal morphology, and better postoperative best-corrected visual acuity. An appropriately powered randomized controlled study is warranted.

Direct modeling of foveal pit morphology from distortion-corrected OCT images.

Inherent distortions affect the spatial geometry of optical coherence tomography (OCT) images and consequently the foveal pit dimensions. Distortion correction provides an accurate anatomical representation of the retinal shape. A novel approach that automatically extracts foveal pit metrics from distortion-corrected OCT images using a sum of Gaussian function is presented. Foveal width, depth and slope were determined in 292 eyes with low fitting errors and high repeatability. Comparisons to undistorted scans revealed significant differences. To conclude, the internal OCT distortions affect the measurements of the foveal pit with their correction providing further insights into the role of foveal morphology in retinal pathologies and refractive development.

POTENTIAL UTILITY OF FOVEAL MORPHOLOGY IN PRETERM INFANTS MEASURED USING HAND-HELD OPTICAL COHERENCE TOMOGRAPHY IN RETINOPATHY OF PREMATURITY SCREENING.

To investigate dynamic foveal morphology with postmenstrual age, in preterm infants with and without retinopathy of prematurity using hand-held optical coherence tomography, adjusting for gestational age (GA) and birthweight (BW). Prospective mixed cross-sectional/longitudinal observational study of 87 participants (23-36 weeks GA; n = 30 with, n = 57 without retinopathy of prematurity) using hand-held optical coherence tomography images (n = 278) acquired between 31 weeks and 44 weeks postmenstrual age excluding treated retinopathy of prematurity. Measurements included foveal width, area, depth, central foveal thickness, maximum slope, and parafoveal retinal thickness at 1,000 µm nasal and temporal to the central fovea. Retinopathy of prematurity was significantly correlated with only foveal width in either GA or BW adjusted statistical models. In contrast, severity of prematurity (GA, BW) correlated with foveal area (P < 0.005), depth (P ≤ 0.001), and slope (P < 0.01), although central foveal thickness (P = 0.007) and parafoveal retinal thickness (P < 0.001) correlated with GA, but not with BW. Foveal width is independent of GA and BW with potential in retinopathy of prematurity screening assessment using hand-held optical coherence tomography. Foveal morphology could be graded in prematurity during development, with possible implications for future management of preterm infants.

Foveal avascular zone morphology and parafoveal capillary perfusion in sickle cell retinopathy

Background/aimsTo assess foveal avascular zone (FAZ) morphology and parafoveal capillary perfusion in patients with various stages of sickle cell retinopathy (SCR) using optical coherence tomography angiography (OCT-A).MethodsThis is a multi-institutional...

Fundus-Controlled Dark Adaptometry in Young Children Without and With Spontaneously Regressed Retinopathy of Prematurity.

PurposeWe correlate dark adaptation course with foveal morphologic alterations in preterm and term-born children using a modified fundus-controlled perimeter and spectral domain–optical coherence tomography (SD-OCT) imaging.MethodsWe performed fundus-controlled chromatic dark adaptometry in premature children aged 6 to 13 years without retinopathy of prematurity (no-ROP; n = 61) and with spontaneously regressed ROP (sr-ROP, n = 29), and in 11 age-matched term-born children. The degree of macular developmental arrest (MDA), defined as a disproportion of the outer nuclear layer to inner retinal layers in the fovea (ONL+/IRL-ratio), was analyzed with the DiOCTA tool in SD-OCT scans.ResultsChildren with MDA showed a flatter dark adaptation course progression with a significant rod-mediated sensitivity recovery delay (0.0113 vs. 0.0253 dB/s; P < 0.001). Preterm-born children with regular foveal morphology reached the final rod-mediated dark-adapted threshold at 12 minutes after bleach at 18.8 dB, compared to after 18.7 minutes at 17.6 dB in children with MDA (no significant difference in final threshold; P = 0.773). The cone-mediated dark adaptation progression showed a significant lower final threshold in children with MDA (6.0 vs. 8.1 dB; P = 0.004).ConclusionsChanges in dark adaptation were seen in the presence of MDA observed in premature children in the no-ROP and sr-ROP groups. MDA in former premature children is associated with functional deficits of cone and rod photoreceptor visual pathways.Translational RelevanceMorphologic alterations in the central retina of premature children, evident in SD-OCT, are associated with long-term functional deficits in the rod and cone pathways, particularly evident in the rod dark adaptation course measured at 12° eccentricity. This indicates a more widespread retinal functional pathology not limited to the fovea, but occurring together with foveal alterations best defined as MDA.

Intravitreal injection of C3F8 in the treatment of vitreomacular traction syndrome

Objective To evaluate the efficacy of single intravitreal injection of C3F8 in treating vitremacular traction (VMT) syndrome. Methods A retrospective case series of 38 eyes of 36 patients affected with VMT syndrome in Department of Ophthalmology, Central Theater Command General Hospital from March 2016 to June 2017 were enrolled in this study. There were 16 males (16 eyes) and 20 females (22 eyes), with the mean age of 64.11±9.49 years and the mean courses of 151.55±127.87 days. All the patients received an intravitreal injection of 0.3 ml of 100% C3F8 within one week. The BCVA examination was performed using the international standard visual acuity chart, which was converted into logMAR visual acuity. The severity of metamorphopsia was detected using M-charts. The extent of vitreomacular adhesion (VMA), central macular thickness (CMT) and the status of ellipsoid zone (EZ) were assessed with spectral-domain OCT at baseline and each month after treatment. The average BCVA was 0.58±0.22. The mean horizontal metamorphopsia (MH) and vertical metamorphopsia (MV) were 0.34±0.30 and 0.50±0.42, respectively. The mean CMT was 415.15±89.59 μm. The mean horizontal VMA was 1168.68±400.61 μm (30 eyes with VMA≤1500 μm and 8 eyes with VMA>1500 μm). The mean vertical VMA was 976.89±295.92 μm. There were 22 eyes with integrity EZ and 16 eyes without integrity EZ, 33 eyes with crystalline lens and 5 eyes with IOL. The mean follow-up time was 10.7 months. The differences in BCVA, MH, MV, CMT, the integrity of EZ before and after treatment were analyzed. The VMT release rates were assessed. The Spearman rank correlation analysis was performed to investigate the relationship of VMT release rates with the data at baseline. Results Vitreomacular traction release occurred in 29 of 38 eyes by the final follow-up visit, the VMT release rate was 76.3%. VMT release occurred and the average time of VMT release occurred was 2.2 weeks. VMT persisted in 7 eyes, in the rest two eyes, one eye developed a retinal detachment and another eye formed macular hole, both eyes responded to vitrectomy. At 6 months after treatment, the average logMAR BCVA was 0.43±0.23, the mean MH and MV were 0.25±0.23 and 0.24±0.23, the mean CMT was 310.61±63.10 μm. Among 16 eyes without integrity EZ before treatment, there were 9 eyes with integrity EZ at 6 months after treatment. There were 16 eyes with integrity EZ and 9 Compared with baseline, the mean BCVA at 6 months after treatment was significantly increased (F=3.779, P=0.037), but the MV (F=4.958, P =0.003) and CMT (F=13.419, P<0.001) were significantly decreased, the integrity of EZ was improved significantly (χ2=5.050, P=0.025). The VMT release correlated inversely with the extent of horizontal VMA, BCVA, and CMT at baseline (r=-0.514, -0.348, -0.429; P=0.009, 0.001, 0.038). Conclusion Intravitreal injection of C3F8 can induce a posterior vitreous detachment and release vitreomacular traction, it is an efficient and safe treatment for VMT syndrome. It can improve the visual acuity, metamorphopsia and foveal morphology in patients with VMT syndrome. Key words: Noble gases/therapeutic use; Treatment outcome; Vitreomacular traction syndrome

Cone-Mediated Function Correlates to Altered Foveal Morphology in Preterm-Born Children at School Age.

To correlate cone- and rod-mediated function with morphology of the macula in preterm-born children without and with spontaneously regressed retinopathy of prematurity (ROP). We performed spectral-domain optical coherence tomography (SD-OCT) single scans in the macular center of preterm-born children aged 6 to 12 years (mean ± SD, 7.4 ± 1.8) without ROP (noROP; n = 59) and with spontaneously regressed ROP (srROP; n = 34), documented with wide-angle digital imaging during routine screening for acute ROP, and compared the data from 14 age-matched term-born children. SD-OCT data were compared to functional cone- and rod-mediated results of scotopic and photopic chromatic pupillometry (cP) and two-color fundus-controlled perimetry (2C-FCP). SD-OCT showed a shallowed foveal pit with significantly reduced outer nuclear layer to inner retinal layer ratio, indicating macular developmental arrest (MDA). MDA was present in 44% of the srROP and 27% of the noROP children. Pupil reaction to photopic red stimuli on blue background showed significantly lower values in all preterm-born children with MDA. In accordance, photopic light increment sensitivity (LIS) to red stimuli in the foveal center on the 2C-FCP was also significantly reduced in children with MDA. Under scotopic conditions, no significant differences were apparent in both pupil reaction with cP and LIS with 2C-FCP. Both objective pupillary response to cone-mediated photopic red stimuli and subjective central cone-mediated results in fundus-controlled perimetry were reduced in preterm-born children with MDA. MDA was present in a significant number of patients with srROP, but also without ROP.

Spectral Domain Optical Coherence Tomography in Detecting Sub-Clinical Retinal Findings in Asian Indian Children with Down Syndrome

ABSTRACTPurpose: Trisomy 21, also known as Down syndrome (DS), is the most common trisomy worldwide. Although ocular associations have been reported, retinal anatomy and pathology remain uninvestigated. We evaluate the role of spectral domain optical coherence tomography (SD-OCT) in analyzing foveal morphology of children with DS.Methods: Nineteen consecutive DS children and eight controls were enrolled under a cross-sectional study in an institutional practice. All subjects underwent SD-OCT imaging on a hand-held device. The morphology and thickness of central fovea, inner retinal layers, outer retina, and photoreceptor layers were measured and compared with age-group sub-analysis.Results: Mean age of the cases was 24 months (3–78 months). All cases and controls had a normal fundus on ophthalmoscopy and foveal thickness was comparable (p = 0.718). Inner retinal fusion was complete in the foveal center in only three eyes (15.8%) of cases compared to all eyes (100%) of controls (p < 0.001). The outer plexiform layer was normal in 10 eyes of cases (52.6%) compared to all eyes (100%) of the controls. Only 10 eyes of DS (52.6%) had a normal external limiting membrane, compared to all eyes of controls (100%, p = 0.01). The interdigitation zone (outer segment) was normal in one (5.3%) case compared to eight (67%) controls (p = 0.001). On subgroup analysis, in older cohorts, cases had a greater proportion of abnormal layers compared to controls. Visual acuity was found to be lower in cases when compared to controls, although not significant (p = 0.19).Conclusion: DS babies have abnormal foveal morphology and persistence of inner retinal layers. This may assist our understanding of their visual development.

Retinal Microvascular Abnormalities in Children with Type 1 Diabetes Mellitus Without Visual Impairment or Diabetic Retinopathy.

To study the characteristics and associated factors of retinal microvascular abnormalities in children with type 1 diabetes mellitus (T1DM) without visual impairment and diabetic retinopathy (DR). Case-control hospital-based study including children with or without DM. Optical coherence tomography angiography (OCTA; CIRRUS HD-OCT model 5000) was used to scan 6 × 6 mm square area of posterior retina and optic disc. The indexes analyzed mainly included vascular length density (VD), perfusion density (PD), and foveal avascular zone area, perimeter, and morphology. Independent risk factors were analyzed by multifactor linear regression. A total of 47 children with T1DM and 44 healthy subjects were enrolled. Statistical analysis showed that VD within 1 to 3 mm (inner ring) of the macula in the case group was smaller than that in the control group (18.561 ± 1.151/mm: 19.161 ± 0.464/mm; P< 0.001), and mother's excessive weight gain during pregnancy was an independent factor (P = 0.004); VD within 3 to 6 mm (outer ring) of the macula in the case group was smaller than that in the control group (19.044 ± 0.847/mm; 19.404 ± 0.496/mm, P = 0.029), while serum creatinine level was revealed to be an independent factor (P = 0.009); PD within 3 to 6 mm of the macula in the case group was higher than that in the control group (0.456 ± 0.015: 0.442 ± 0.030) (P = 0.003), with no independent factor observed in regression analysis. Retinal microvasculopathy had already occurred in the parafoveal area of diabetic children without visual impairment and DR; early screening and close follow-up were recommended for children with high-risk factors.

A new method to assess foveal morphology with optical coherence tomography.

Tomeasure foveal morphology using optical coherence tomography (OCT). Three examiners classified normal subjects and patients with macular edema and epiretinal membranes from a normative database (299 OCT scans) and a study sample (80 OCT scans) on the basis of the foveal depression appearance (reference classification). The following parameters were measured for each OCT scan: Central Foveal Thickness (CFT), Central Subfield Thickness (CST), Central Subfield Volume (CSV), Centrofoveal Index (CI), Parafoveal Index (PI), and Foveal Indices (FI1, FI2, FI3). Foveal depression of OCT scans in the study sample were classified based on the values of OCT parameters using Bayesian statistics (test classifications). Agreement between reference and test classifications was of 70% for CFT, 58.7% for CST, 60% for CSV, 80% for CI, 72.5% for PI, 88.7% for FI1, 96.2% for FI2 and 97.5% for FI3. IF3 seems to provide a reliable measure of the foveal morphology.