Inferior Visual Field Research Articles

Meridional Anisotropy of Foveal and Peripheral Resolution Acuity in Adults With Emmetropia, Myopia, and Astigmatism.

PurposeTo quantify astigmatism-related meridional anisotropy in visual resolution at central, nasal, and inferior visual fields.MethodsThree groups of young adults (range, 18–30 years) with corrected-to-normal visual acuity (logMAR 0) were recruited: (1) myopic astigmats (MA): spherical-equivalent error (SE) < −0.75D, with-the-rule astigmatism ≥ 2.00D, n = 19; (2) simple myopes (SM): SE < −0.75D, astigmatism ≤ 0.50D, n = 20; and (3) emmetropes (EM): SE ± 0.50D, astigmatism ≤ 0.50D, n = 14. Resolution acuity was measured for the horizontal and vertical gratings at central and peripheral visual fields (eccentricity: 15°) using a 3-down 1-up staircase paradigm. On- and off-axis refractive errors were corrected by ophthalmic lenses.ResultsThe MA group exhibited meridional anisotropy preferring vertical gratings. At the central field, the MA group had better resolution acuity for vertical than horizontal gratings, and their resolution acuity for horizontal gratings was significantly worse than the SM and EM groups. At peripheral visual fields, both the SM and EM groups showed better resolution acuity for the radial (i.e., nasal field: horizontal gratings; inferior field: vertical gratings) than tangential orientation. However, the MA group tended to have better resolution acuity for the tangential orientation (i.e., vertical gratings), and their resolution acuity for horizontal gratings was significantly lower than the SM and EM groups at the nasal field. No significant differences were found in the inferior field among the three groups.ConclusionsThis study provided evidence of astigmatism-related meridional anisotropy at the fovea and nasal visual fields, underscoring the significant impact of astigmatism on orientation-dependent visual functions.

Bilateral Non Arteritic Anterior Ischemic Optic Neuropathy Associated With Optic Nerve Head Drusen And Vascular Risk Factors

We report case history of 52 year old male who presented with sudden painless diminution of vision in right eye and with similar complaint of diminution of vision in left eye six months back. He was diagnosed as Nonarteritic Anterior Ischemic Optic Neuropathy (NAION) in left eye with Optic Nerve Head Drusen (ONHD) in both the eyes. He was otherwise well and his medical history revealed systemic hypertension. Fundus examination revealed hyperaemic disc in the right eye and temporal pallor of the disc in the left eye. On visual field examination, inferior altitudinal visual field defect in both the eyes.ONHD can mimic as disc oedema and it can very rarely cause NAION. In addition, multiple vascular risk factors can also cause NAION, hence detailed investigations and periodic follow up should be done to rule out ischemic disc complication.

Disc Hemorrhages Are Associated With Localized Three-Dimensional Neuroretinal Rim Thickness Progression in Open-Angle Glaucoma

• PURPOSE:To evaluate the relationship between the occurrence of optic disc hemorrhages (DH) and glaucoma progression as determined by multiple glaucoma testing modalities.• DESIGN:Prospective cohort study.• METHODS:A longitudinal study was undertaken of 124 open-angle glaucoma patients who had yearly disc photography, visual fields (VFs), spectral-domain optical coherence tomography (SD-OCT), retinal nerve fiber layer (RNFL) thickness scans, and optic nerve volume scans (Spectralis), all performed on the same day over a 5-year period. The minimum distance band (MDB) thickness, a 3-dimensional (3D) neuroretinal rim parameter, was calculated from optic nerve volume scans. Patients were classified as glaucoma progressors or glaucoma nonprogressors using event-based analysis.• RESULTS:Of 124 open-angle glaucoma patients, 19 (15.3%) had 1 or more DHs on yearly disc photographs. Presence of a DH was associated with localized 3D neuroretinal rim thickness progression (superior MDB progression; odds ratio: 3.96; P = .04) but not with global or inferior MDB progression (P = .14 and .81, respectively), DP progression (P = .08), VF progression (P = .45), or RNFL global, inferior, or superior progression (P = .17, .26, and .76, respectively). In the majority of patients with MDB progression (14/17 or 82%), the progression was noted before or concurrently with the first instance of DH.• CONCLUSIONS:Glaucoma progression detected by high-density 3D SD-OCT neuroretinal rim measurements preceded DH occurrence in the majority of patients. These findings support the hypothesis that DHs are indicators of ongoing glaucoma progression rather than discrete events that cause subsequent progression.

Adaptation to post-stroke homonymous hemianopia – a prospective longitudinal cohort study to identify predictive factors of the adaptation process

Purpose To determine any factors that predict how an individual will adapt to post-stroke hemianopic visual field loss, with close monitoring of the adaptation process from an early stage. Materials and methods The Hemianopia Adaptation Study (HAST) is a prospective observational longitudinal cohort clinical study. Adult stroke survivors (n = 144) with new onset homonymous hemianopia were monitored using standardised mobility assessment course (MAC) as the primary outcome measure of adaptation. Results Several baseline variables were found to be good predictors of adaptation. Three variables were associated with adaptation status at 12-weeks post-stroke: inferior % visual field, % total MAC omissions, and MAC completion time (seconds). Baseline measurements of these variables can predict the adaptation at 12 weeks with moderate to high accuracy (area under ROC curve, 0.82, 95% CI 0.74–0.90). A cut-off score of ≤25% target omissions is suggested to predict which individuals are likely to adapt by 12-weeks post-stroke following gold standard care. Conclusions Adaptation to hemianopia is a personal journey with several factors being important for prediction of its presence, including MAC outcomes and extent of inferior visual field loss. A clinical recommendation is made for inclusion of the MAC as part of a functional assessment for hemianopia. Implications for rehabilitation The mobility assessment course (MAC) should be considered as an assessment of mobility/scanning in the rehabilitation of patients with homonymous hemianopia. A cut-off score of ≤25% omissions on MAC could be employed to determine those likely to adapt to hemianopia long-term. Targeted support and therapy for patients with significant visual loss in the inferior visual field area should be considered.

Topographic Quadrant Analysis of Peripapillary Superficial Microvasculature in Optic Disc Drusen.

Background: Limited information is known about the topographic effect of optic disc drusen (ODD) on peripapillary retinal nerve fibers and microvasculature.Objective: This study aims to understand the structural and functional impact of ODD in different quadrants of the optic disc.Methods: We performed a retrospective case-control study of 22 ODD patients (34 eyes) and 26 controls (33 eyes) to compare optical coherence tomography (OCT) retinal nerve fiber layer (RNFL), OCT angiography (OCTA), and corresponding static perimetry mean deviation (MD) calculated using the modified Garway-Heath map in different quadrants of the optic disc. OCTA was analyzed using custom MATLAB script to measure six parameters in a peripapillary annulus with large vessel removal: vessel area density (VAD), vessel skeleton density (VSD), vessel perimeter index (VPI), vessel complexity index (VCI), flux, and vessel diameter index (VDI).Results: Quadrant analysis revealed that OCTA VAD and VCI were significantly decreased in superior, nasal, and inferior but not temporal quadrant. RNFL, VSD, and VPI were significantly impacted only in the superior and nasal quadrants. Corresponding visual field MDs in all ODD eyes were not different in the four quadrants, although eyes with MD equal or worse than −5 dB (32%) had worst visual field corresponding to the superior quadrant of the optic disc (inferior arcuate visual field). Structure-structure comparison of OCT and OCTA showed high correlation of RNFL with multiple OCTA measurements in the superior, nasal, and inferior quadrants but not temporal quadrant. Structure-function analysis revealed significant correlation of VAD and VCI and visual field MD in every quadrant, but RNFL was only significantly correlated in the superior and inferior quadrants.Conclusions: Peripapillary VAD and VCI are decreased in more quadrants than RNFL, supporting the clinical utility of performing OCTA in addition to OCT. Consistent with the most common locations of ODD, five OCT/OCTA measurements (VAD, VCI, RNFL, VSD, VPI) are decreased in the superior and nasal quadrants. OCT/OCTA measurements were significantly impacted in contrast to the relatively mild effect on corresponding visual field MD, consistent with the idea that a decrease in objective structural and vascular measurements occurs without parallel change in subjective visual function in ODD.

Mouth-nose masks impair the visual field of healthy eyes.

BackgroundMouth-nose masks have been requested to prevent the transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The aim of the present study was to investigate, if wearing a mouth-nose mask impairs the visual field function in normals.MethodsThirty eyes of 30 subjects were recruited for the present study. White-on-white perimetry (OCTOPUS 900; 90°) was done and sensitivity was analysed in 14 defined test points (P1-P14, inferior visual field) under 3 different test conditions while the subjects were wearing a mouth-nose mask: (I) 1.5 cm under the lower eyelid, nose clip not used (position1.5cm_no_clip); (II) 1.5 cm under the lower eyelid, nose clip correctly positioned (position1.5cm_with_clip); (III) 0.5 cm under the lower eyelid, nose clip correctly positioned (position0.5cm_with_clip). All data were compared to sensitivity without wearing a mouth-nose mask (reference). Mean Δ was calculated, being the difference between the results of each test condition and reference, respectively.ResultsSensitivity was significantly different between position1.5cm_no_clip and reference at 10 test points (p<0.05). Sensitivity at test point P7 was significantly different between position1.5cm_with_clip and position0.5cm_with_clip compared to reference (p<0.001), respectively. Mean Δ increased while wearing a mask at P7: position1.5cm_with_clip (-8.3 dB ± 7.3 dB) < position0.5cm_with_clip (-11.3 dB ± 9.5 dB) < position1.5cm_no_clip (-20.1 dB ± 7.6 dB).ConclusionVisual field function was observed to be significantly impaired in the inferior-nasal sector while persons were wearing a mouth-nose mask, especially when the nose clip was not correctly used.

Comparison of Superior and Inferior Visual Field Asymmetry Between Normal-tension and High-tension Glaucoma.

Increased severity of glaucoma heightened the hemispherical asymmetry in normal-tension and high-tension glaucoma (NTG/HTG), especially NTG. NTG showed localized superior defects in the central and paracentral areas whereas HTG showed mild asymmetry with diffuse defects. The purpose of this study was to compare the patterns of visual field (VF) defects according to glaucoma severity in NTG and HTG. A total of 1458 eyes with NTG (936) and HTG (522) were classified by mean deviation values into mild, moderate, and severe. The mean total deviation (mTD) values for each nasal, central, paracentral, arcuate 1, and arcuate 2 region of the Glaucoma Hemifield Test (GHT) were calculated. The differences in mTD between the superior and inferior hemifields of NTG and HTG were compared, and the degree of hemifield asymmetry was plotted. In NTG and HTG, the mTDs of the 5 regions of the superior GHT were significantly worse than those of the corresponding regions of the inferior GHT at all severity levels except for mild HTG. However, NTG showed significantly greater asymmetry than HTG in 2 regions at mild, 3 at moderate, and all 5 at severe. Moderate and severe NTG showed severe asymmetry with localized superior field defects concentrated at the central and paracentral areas with >8 dB asymmetry. However, in all HTG groups showed mild asymmetry with diffuse defects. The superior hemifield was more severely affected than the inferior hemifield in NTG and HTG. As the severity of glaucoma increased, so did the asymmetry in both groups, with NTG showing more profound asymmetric VF defects in the central and paracentral areas whereas HTG did not. Different VF patterns suggest differing pathologic mechanisms and possible need for different therapeutic strategies in NTG and HTG.

Peripheral vision and hazard detection with average phakic and pseudophakic optical errors.

The impact of peripheral optical errors induced by intraocular lenses was evaluated by simulating the average phakic and pseudophakic image qualities. An adaptive optics system was used to simulate the optical errors in 20° nasal and inferior visual field in phakic subjects. Peripheral resolution acuity, contrast sensitivity and hazard detection were evaluated. Pseudophakic errors typical for monofocal designs had a negative effect on resolution acuity and contrast sensitivity and the hazard detection task also showed increased false positive and misses and a longer reaction time compared to phakic optical errors. The induced peripheral pseudophakic optical errors affect the peripheral visual performance and thereby impact functional vision.

Location and stability of the preferred retinal locus in native Persian‐speaking patients with age‐related macular degeneration

ABSTRACT Clinical relevance The findings of this study can be used in the selection of the preferred retinal locus to establish better rehabilitation services such as eccentric viewing training for patients with age‐related macular degeneration. Background The aim of this study was to determine the characteristics of the preferred retinal locus in native Persian‐speaking patients with age‐related macular degeneration. Methods In this non‐interventional case series, all patients with a diagnosis of age‐related macular degeneration referred to the Retina Clinic of the Rassoul Akram Hospital, Tehran, Iran, were evaluated. The fixation characteristics were evaluated monocularly using the MP1 microperimeter (Nidek Technologies, Padua, Italy). Optical coherence tomography was used to determine the location of the central fovea. The images were overlaid and the preferred retinal locus‐fovea distance was measured using Image J software. Results Fifty‐one eyes of 35 patients with a mean age of 73.8 ± 7.7-years were evaluated in this study. Inferior‐field, left‐field, central‐field, right‐field, and superior‐field preferred retinal locus were detected in 49 per cent, 33.3 per cent, 7.8 per cent, 5.9 per cent, and 3.9 per cent of the subjects, respectively. Fixation was stable in 70.6 per cent, relatively unstable in 15.7 per cent, and unstable in 13.7 per cent of the participants. Significant differences were not found in the mean values of logMAR visual acuity between different fields of the preferred retinal locus after Bonferroni correction (p = 0.031). Analysis of co‐variance showed no significant difference in mean sensitivity values between different locations of the preferred retinal locus (p = 0.07). The mean preferred retinal locus‐fovea distance was not significantly different between different fields of the preferred retinal locus (p = 0.063). Conclusions Native Persian‐speaking patients with central scotoma secondary to age‐related macular degeneration place their self‐selected preferred retinal locus most frequently in the inferior and left visual field, which would result in scotoma displacement to the superior and right visual field. Fixation stability was statistically similar in different locations of preferred retinal locus, but it improved with decreasing the preferred retinal locus‐fovea distance.

Impact of binocular visual field loss on driving performance in glaucoma patients.

To evaluate the driving performance in young and middle-aged Chinese glaucoma patients with mild to severe visual field loss compared to those without glaucoma by using a driving simulation test. Twenty-nine participants were included in this study: nine patients with glaucoma but pass the binocular Esterman visual field test, ten patients with glaucoma and fail the binocular Esterman visual field test, and ten age-matched healthy controls. A driving simulation test was designed as a frequency-based analysis of a lane-keeping task. The total performance error, the control-response amplitude and delay were calculated. Esterman visual field test fail group showed the longest delay of control-response among three groups (P=0.02). And the delay in lane-keeping task was significantly associated with inferior field of better-eye (r=0.51, P=0.004) and integrated visual field (r=0.55, P=0.002). Young and middle-aged glaucoma patients with binocular visual field loss suffered from a longer delay of response in driving simulation test, while inferior visual field having more impact than superior visual field.

The Impacts of Face Mask Use on Standard Automated Perimetry Results in Glaucoma Patients.

The coronavirus disease 2019 (COVID-19) spread rapidly worldwide, causing a severe outbreak. Because the disease is easily transmitted, face masks are a vital tool to slow the spread. The aim of this study is to investigate the impacts of face mask use on standard automated perimetry (SAP) results in glaucoma patients. All follow-up glaucoma patients who underwent SAP between May and October 2020 were enrolled in this study. In patients with low test reliability and/or visual field changes, SAP was repeated after repositioning and taping patients' face masks. A total of 127 patients (59 female and 68 male) with a mean age of 59.8±10.3 years were included in the study. While 101 patients (79.5%) wore surgical face masks, 26 patients (20.5%) wore cloth face masks. Low SAP reliability appeared in 23 patients (18.1%), and inferior visual field defects were present in 3 patients (2.4%). The main effects of poorly fitting face masks on SAP reliability were increased fixation losses and false-positive errors (for both, P=0.001). Low SAP reliability was significantly higher in patients wearing cloth face masks than in those wearing surgical face masks (47.8% vs. 9.9%; P=0.0001). The face mask-related fogging of eyeglasses before SAP is a strong predictor of fogging of the trial lenses-related low SAP reliability (odds ratio: 27, 95% confidence interval: 5.48-132.92, P=0.0001). In all repeated SAPs, the patients' reliability parameters improved, and inferior visual field artifacts disappeared. Unsuitable face masks can cause either visual field artifacts, which may be interpreted as glaucoma progression or low test reliability. Taping the face masks' upper edges is an effective technique to prevent visual field artifacts and obtain good test reliability.

Paracentral and Cecocentral Scotomas After Pars Plana Vitrectomy for Rhegmatogenous Retinal Detachment

To describe novel paracentral and cecocentral visual scotomas after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) repair over a 5-year period. Retrospective case series. This was a retrospective review of all patients who reported visual scotomas after 23- or 25-gauge PPV (Constellation Vision System, Alcon, Fort Worth, Texas, USA) for RRD repair by a single surgeon (RNK) from January 2013 through December 2018. All patients had multimodal imaging (fundus photography, fluorescein angiography, autofluorescence, and spectral-domain optical coherence tomography [OCT] and standardized central Humphrey visual field [HVF] testing) to further characterize the visual scotomas. Nine patients reported visual scotomas after PPV for RRD from January 2013 to December 2018 with incidence of 6.4% (9/140). The average age was 61 years (range 53-71 years) and 3 of 9 were female. The preceding RRD was macula-sparing for 6 of 9 patients; all of them involved the right eye. Seven of 9 patients reported the central scotoma within the first week after surgery. All 9 patients noted paracentral or cecocentral location of scotomas involving the inferior temporal visual field. Multimodal imaging was only significant for corresponding focal superior nasal ganglion cell loss on spectral-domain OCT. Two of 9 patients had symptomatic visual loss from the scotoma because it involved the center of fixation. We report a novel central/paracentral visual field defect after PPV for RRD repair. The paracentral scotoma is located inferotemporally and correlates anatomically with ganglion cell loss on spectral-domain OCT. The visual field defect and corresponding anatomic ganglion cell loss suggests a focal retinal injury. We propose that it could be caused by trauma from air flow from the infusion cannula during the air-gas exchange, angled directly toward the superior nasal paracentral retina. Surgeons should be aware of this complication and take precautions to slowly inject the gas after the air-gas exchange.

Hemisphere opposite to vascular trunk deviation is earlier affected by glaucomatous damage in myopic high-tension glaucoma.

PurposeTo investigate whether the position of the central vascular trunk, as a surrogate of lamina cribrosa (LC) shift, is associated with the initial hemisphere of visual field defect in myopic high-tension glaucoma (HTG) eyes.MethodsThe deviation of the central vascular trunk was measured from the center of the Bruch’s membrane opening (BMO), which was delineated by OCT imaging. The angular deviation was measured with the horizontal nasal midline as 0° and the superior location as a positive value. The initial hemisphere developing visual field defect was defined as three connected abnormal points (having a P value with less than 0.5% probability of being normal) appearing in only one hemisphere in pattern deviation plots. If those points were observed in both hemispheres initially, the eye was classified as bi-hemispheric visual field defect.ResultsInitially, 36 eyes (44%) had superior visual field defects, 27 (33%) inferior visual field defects, and 18 (22%) bi-hemispheric visual field defects. After a mean follow-up of 5 years, the number of bi-hemispheric visual field defects had increased to 34 (42%). A logistic regression analysis revealed that inferior deviation of vascular trunk was the only factor associated with initial inferior visual field defect (P = 0.001), while initial bi-hemispheric visual field defects were associated with worse mean deviation at initial visits (P<0.001). A conditional inference tree analysis showed that both the angular deviation (P<0.001) and initial mean deviation (P = 0.025) determined the initial hemispheres developing visual field defect.ConclusionsAlthough both hemispheres were involved as glaucoma progression, the axons on the side counter to the vascular trunk deviation were damaged earlier in HTG. This finding implies the LC shift could add additional stress to axons exposed to high intraocular pressure.

Usefulness of Optical Coherence Tomography Angiography in the Differential Diagnosis Between Superior Segmental Optic Hypoplasia and Normal-tension Glaucoma

The differential diagnosis of superior segmental optic hypoplasia (SSOH) and normal-tension glaucoma (NTG) is an issue in the ophthalmologic field. To date, several modalities have been developed to solve this issue; however, no standard methods have been established. Recently, optical coherence tomography angiography (OCTA) has been introduced to better evaluate the volumetric angiography images. Therefore, in this study, we investigated the usefulness of OCTA in differentiating between SSOH and NTG. In this retrospective study, we included 26 patients with SSOH who had definite visual field defects and 40 patients with NTG who had only inferior visual field defects. Age, sex, intraocular pressure, refractive error, retinal nerve fiber layer thickness, and visual field defects were compared between the groups. In addition, we analyzed and compared the peripapillary vessel density (VD) measured on OCTA between the groups. The area under the receiver operating characteristic curves were obtained for each parameter. On Cirrus HD-OCT, the retinal nerve fiber layer in patients with SSOH was thinner in the superonasal segment and thicker in the superotemporal segment compared with patients with NTG. In the analysis of OCTA, the peripapillary VD of the superonasal segment was significantly lower in the SSOH group than in the NTG group, while it was significantly higher in the superotemporal segment in the SSOH group than in the NTG group. The optimal superonasal-to-superotemporal ratio cutoff was 0.8828, with a sensitivity of 95% and specificity of 92.3%, for the diagnosis of SSOH (area under the receiver operating characteristic curve=0.962). Our findings suggest that the superonasal-to-superotemporal VD ratio measured on OCTA may be used to distinguish between SSOH and NTG. However, further large-scale studies are required to verify our findings.

Evaluation of Fear of Falling in Patients with Primary Open-Angle Glaucoma and the Importance of Inferior Visual Field Damage.

PurposeTo evaluate fear of falling using the Fall Efficacy Scale-International (FES-I) in glaucoma patients and investigate its association with glaucomatous visual field loss.MethodsThis study included 273 patients (160 men and 113 women, average age 64.2 years) with primary open-angle glaucoma. Participants were requested to answer the FES-I questionnaire, translated into Japanese, in a face-to-face interview. The relationship between total FES-I score and the following variables was analyzed using multivariable linear regression: age, sex, better and worse best corrected visual acuity, total deviation (TD) in four visual field areas, body mass index (BMI), minutes walked per day, history of diabetes mellitus, history of systemic hypertension, number of previous falls.ResultsUnivariate analysis suggested that total FES-I score increased with age and in woman, whereas other variables were not significantly associated with total FES-I score. However, age (coefficient, 0.23; standard error [SE], 0.04; P < 0.001), sex (coefficient, 1.79 for women; SE, 0.84; P = 0.034), mean TD in the inferior central area (coefficient, 0.92; SE, 0.22; P <0.001), and mean TD in the inferior peripheral area (coefficient, –0.86; SE, 0.21; P < 0.001) were included in the optimal model for total FES-I score.ConclusionsInferior peripheral visual field damage and preserved inferior central visual field sensitivity were associated with increased fear of falling assessed with FES-I in glaucoma.

Successful Systemic Lysis Therapy in Acute Retinal Arterial Occlusions

Retinal artery occlusion leads to dramatic and irreversible vision loss. There is currently no evidence-based standard therapy. According to the German guidelines on retinal artery occlusions, intravenous fibrinolysis therapy can be performed up to a time window of 4 h 30 min. Two patients were treated accordingly. In patient 1, systemic lysis therapy was used in branch retinal artery occlusion (BRAO) of the inferior temporal retinal artery with macular involvement 4 h 15 min after symptom onset. Immediately after the therapy, the patient reported significant improvement in symptoms. Three months after therapy, retinal function was good, but with subtle atrophy of the inner neurosensory retina. Patient 2, 2 h 30 min after onset of symptoms of the inferior temporal BRAO, the patient experienced further deterioration, with clinical signs of a central retinal artery occlusion (CRAO). Visual acuity deteriorated to light perception. Emergency intravenous lysis therapy, administered 3 h later, gave an improvement in visual acuity with preservation of the inferior visual field. In both patients, a marked improvement in visual acuity was observed immediately after the lysis therapy: Patient 1: right eye, best corrected visual acuity (BCVA) initial 0.5, BCVA 3 days after lysis therapy 1.0, no defects in Goldmann visual field. Patient 2: left eye, BCVA initial 0.4, then sudden deterioration to light perception, BCVA 1 month after lysis therapy 0.6, persisting visual field defects in the superior hemisphere with preservation of the inferior visual field. Two patients with acute retinal artery occlusion were treated successfully with systemic intravenous fibrinolysis.

Atypical presentation of optic neuritis with unilateral inferior altitudinal visual field defect in multiple sclerosis

Background: The purpose of this paper was to report a case of retrobulbar optic neuritis as the first manifestation of multiple sclerosis, with atypical presentations which include a sudden painless reduction in vision, without optic disc swelling and presence of unilateral inferior altitudinal visual field defect. Case report: A 17-year-old girl presented to our clinic with right eye sudden painless drop in visual acuity to counting finger associated with headache. Her right eye optic nerve function tests were positive, but her optic disc was not swollen. Bjerrum’s visual field chart noted right eye unilateral inferior altitudinal visual field defect with foveal involvement. Her blood investigations were normal, and magnetic resonance imaging (MRI) of brain and orbit was suggestive of multiple sclerosis. She was commenced on three days of high dose intravenous steroi, and was referred to neuromedical team for further management. At 3-month follow up, her right eye visual acuity improved to 6/6 with the restoration of normal colour vision. Conclusions: In presence of atypical presentation of optic neuritis, multiple sclerosis must be thought of especially in young patients. Hence early co-management with neuromedical discipline is important to reduce the frequency and severity of attacks in the future.

A Nomenclature to Describe the Sequence of Visual Field Defects in Progressive Thyroid Eye Disease–Compressive Optic Neuropathy (An American Ophthalmological Society Thesis)

To create a novel nomenclature to characterize the longitudinal sequence of visual field (VF) defects in patients with progression of thyroid eye disease-compressive optic neuropathy (TED-CON). A retrospective review of records from 1 institution identified patients with progressive Humphrey VF defects secondary to TED-CON. The VF defects were analyzed by 2 independent reviewers and classified into 1 of 10 categories, divided into 3 stages that reflect the observed progression pattern, plus a miscellaneous category (stage X). Stage 1 VF defects are the earliest detectable and involve the inferior visual field with 3 levels of severity. Stage 2 VF defects include 2 distinguishable levels of severity and occur as the inferior defects advance above the horizontal midline to involve the superior VF. Stage 3 involves progression of stage 2 VF defects to complete loss of inferior and superior hemifields. Of 234 VFs in 37 eyes of 23 subjects, inferior defects were most common, including stage 1a (small inferior paracentral defect) in 22 of 234 VFs (9.4%), stage 1b (large inferior paracentral defect) in 112 of 234 VFs (47.9%), and stage 1c (inferior altitudinal defect) in 11 of 234 VFs (4.7%). Stage 2a (inferior altitudinal with superior advancement above the horizontal meridian) occurred in 41 of 234 VFs (17.5%), stage 2b (inferior altitudinal with superior arcuate) occurred in 6 of 234 VFs (2.6%), and stage 3 (total loss) occurred in 5 of 234 VFs (2.1%). The longitudinal sequence of VF defects from the 37 eyes of 23 patients was analyzed. Thirty-one of 37 eyes (83.8%) demonstrated a predictable progression pattern from least to more severe: stage 1a, stage 1b, stage 1c, stage 2a, stage 2b, and stage 3. A reverse order of VF defect progression was noted in 15 eyes with improving TED-CON. A minority of progression patterns (16.2%) originated from stage X (central/paracentral, enlarged blind spot, and scatter). Humphrey VF defects resulting from TED-CON are most often inferior, often have a predictable pattern of progression, and can be categorized into a novel descriptive nomenclature system. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Contrast Energy and Contour Interaction.

Contour interaction describes an impairment of visual acuity produced by nearby flanking features, which exerts a significant impact in many clinical tests of visual acuity. Our results indicate that the magnitude of interaction depends either on the flanker contrast energy (i.e., the product of flanker contrast and width) or the flanker contrast alone, depending on the contrast energy of the flankers. The discrimination of acuity targets is impaired by the presence of nearby flanking contours, a phenomenon known as contour interaction. In this study, we measured percent correct identification for threshold size, high-contrast Sloan letters at the fovea and at 5° in the inferior visual field for different combinations of flanking-bar width, and Weber contrast corresponding to specific fixed values of contrast energy (width × contrast, in %-min arc). For flanking bars with low-contrast energy, contour interaction exhibited no systematic dependence on the flanking-bar width. However, when the flanking bars had higher contrast energy, narrower high-contrast bars produced significantly greater contour interaction than wider bars of lower contrast. The results are consistent with the interpretation that contour interaction depends primarily on the contrast energy of flanking contours when their contrast energy is low. As the contrast energy of the flanking contours increases, the magnitude of contour interaction depends on the flanker contrast. For high-contrast flanking contours, the magnitude of contour interaction saturates when the width of the flanking contours is approximately 20% of letter size.

Investigation of the relationship between macular pigment levels and rod‐mediated dark adaptation in intermediate age‐related macular degeneration

BackgroundIt has been shown that rod‐mediated dark adaptation is significantly delayed in ageing, a change which is exacerbated in age‐related macular degeneration (AMD). Levels of lutein and zeaxanthin, the two main constituents of macular pigment have been found in rod outer segments, indicating that the macular pigment may have an influence on rod‐mediated dark adaptation. The aim of this study was to determine if rod‐mediated dark adaptation is associated with central macular pigment levels in individuals with intermediate stage AMD.MethodsA cross‐sectional observational study included individuals with acuity better than 6/15 Snellen and intermediate stage AMD based on graded fundus photographs using an internationally accepted grading scale. Rod‐mediated dark adaptation was assessed at five degrees eccentricity in the superior retina (inferior visual field) using the rod intercept time measure from the MacuLogix AdaptDx. Macular pigment optical density was measured at 0.5 degrees eccentricity using a heterochromatic flicker photometry‐based method.ResultsTwenty‐seven individuals (mean age 76.7-years) with intermediate stage AMD and 23 age‐matched normal controls (mean age 74.0-years) were recruited. Rod‐mediated dark adaptation was significantly delayed in intermediate stage AMD compared with healthy controls (32.9-minutes versus 10.7-minutes, p < 0.01). There was no statistically significant correlation between the rod intercept time and the level of macular pigment in those with intermediate AMD (r = −0.04, p = 0.85).ConclusionThe results did not support the hypothesis that higher macular pigment is associated with improved rod‐mediated performance or that higher levels of macular pigment protect rod‐mediated function in intermediate AMD.