Response time and response time variability as indicators of response quality during static automated perimetry.

PURPOSE: Perimetry is a both demanding and strenuous examination method that is often accompanied by signs of fatigue, leading to false responses and thus incorrect results. Therefore, it is essential to monitor the response quality. The purpose of this study was to evaluate the response time (RT) and its variability (RTV) as quality indicators during static automated perimetry. METHODS: Size III Goldmann stimuli (25.7') were shown with the OCTOPUS 900 perimeter in four visual field locations with 13 different stimulus luminance levels (0.04-160 cd/m2). An increased rate of false-positive and false-negative catch trials (25% each) served to monitor the response quality simultaneously together with response time recording. Data evaluation was divided into global and individual analysis. For global analysis, the agreement indices (AI, agreement between time periods with an increased number of false responses to catch trials and time periods with pathological response to time-based values set into relation to time periods in which only one of the two criteria was considered pathological) and for individual analysis, the Spearman correlation coefficients were calculated. Ophthalmologically normal subjects with a visual acuity ≥ 0.8, and a maximum spherical/cylindrical ametropia of ± 8.00/2.50 dpt were included. RESULTS: Forty-eight subjects (18 males, 30 females, age 22-78 years) were examined. The total number of false responses to catch trials was (median/maximum): 6/82. RT and RTV were compared to the occurrence of incorrect responses to catch trials. The resulting individual Spearman correlation coefficients (median/maximum) were for RT: ρRT = 0.05/0.35 and for RTV: ρRTV = 0.27/0.61. The global analysis of the RTV showed agreement indices (median/maximum) of AIRTV = 0.14/0.47. CONCLUSIONS: According to this study, an increased portion of catch trials is suitable as a verification tool for possible response quality indicators. The RTV is a promising parameter for indicating the response quality.

Benchmarking Visual Performance with Monofocal Intraocular Lenses with and without Enhanced Optical Properties in a Nighttime Driving Simulator Environment: A Proof-of-Concept Study. / Vergleich der Sehleistung mit monofokalen Intraokularlinsen mit und ohne verbesserte optische Eigenschaften in einem Nachtfahrsimulator: eine Proof-of-Concept-Studie.

BACKGROUND: The purpose of this study is to introduce a method for benchmarking intraocular lenses during driving activities under highly standardized conditions, specifically with regard to visual acuity (VA) and contrast sensitivity (CS). Therefore, patients with intraocular lens (IOL) implants ICB00 (Tecnis Eyhance, Johnson & Johnson, Santa Ana, CA, USA) vs. CNA0T0 (Clareon, Alcon Laboratories Inc., Fort Worth, TX, USA) were examined clinically and in a nighttime driving simulator. PATIENTS AND METHODS: Clinical tests for high (HCVA), low contrast (LCVA) distant VA, and mesopic CS were conducted in subjects at least 2 months after binocular IOL surgery (inclusion criteria: VA > 20/25, ophthalmologically normal, except cataract surgery). All patients completed a straight driving simulator route. VA, CS, and halo size were assessed binocularly during nighttime driving using eight-position Landolt Cs in four different locations and two (far and intermediate) distances. RESULTS: Results are presented as median/interquartile range: ICB00 data (corresponding CNA0T0 data are shown in brackets): 5 (6) subjects, aged 69.6/8.3 (71.1/13.0) years were enrolled. Clinical tests: logMAR HCVA 0.11/0.39 (0.00/0.51), logMAR LCVA 0.78/0.52 (0.80/0.54); logCS without glare 0.50/0.31 (0.30/0.65), logCS with glare 0.20/0.15 (0.20/0.5). Nighttime driving simulator: logMAR VA thresholds for right roadside, dashboard, navigation screen, and interior rear-view mirror were 0.50/0.06 (0.57/0.22), 0.81/0.07 (0.91/0.14), 0.80/0.17 (0.92/0.27), 0.50/0.11 (0.63/0.26); logCS thresholds were1.53/0.67 (1.00/0.81), 0.82/0.11 (0.61/0.19), 0.71/0.14 (0.50/0.15), 0.87/0.07 (0.81/0.11). Halo size: 5.40°/0.89° (5.88°/2.00°). CONCLUSIONS: Within a nighttime driving simulator environment, ICB00 exceeded CNA0T0 in median logMAR (VA) and logCS by 0.1 log unit at intermediate distances (dashboard, navigation screen). The clinical test for far and remote distances did not show a difference. These results confirm benefits of monofocal IOLs with enhanced optical properties for intermediate distances compared to conventional monofocal lenses within the target medium distance ranges.

Organization of area hV5/MT+ in subjects with homonymous visual field defects.

Damage to the primary visual cortex (V1) leads to a visual field loss (scotoma) in the retinotopically corresponding part of the visual field. Nonetheless, a small amount of residual visual sensitivity persists within the blind field. This residual capacity has been linked to activity observed in the middle temporal area complex (V5/MT+). However, it remains unknown whether the organization of hV5/MT+ changes following early visual cortical lesions. We studied the organization of area hV5/MT+ of five patients with dense homonymous defects in a quadrant of the visual field as a result of partial V1+ or optic radiation lesions. To do so, we developed a new method, which models the boundaries of population receptive fields directly from the BOLD signal of each voxel in the visual cortex. We found responses in hV5/MT+ arising inside the scotoma for all patients and identified two possible sources of activation: 1) responses might originate from partially lesioned parts of area V1 corresponding to the scotoma, and 2) responses can also originate independent of area V1 input suggesting the existence of functional V1-bypassing pathways. Apparently, visually driven activity observed in hV5/MT+ is not sufficient to mediate conscious vision. More surprisingly, visually driven activity in corresponding regions of V1 and early extrastriate areas including hV5/MT+ did not guarantee visual perception in the group of patients with post-geniculate lesions that we examined. This suggests that the fine coordination of visual activity patterns across visual areas may be an important determinant of whether visual perception persists following visual cortical lesions.

Retinal nerve fiber bundle trajectories in Chinese myopic eyes: Comparison with a Caucasian based mathematical model.

Previously we developed a mathematical model for describing the retinal nerve fiber bundle (RNFB) trajectories in the human retina. The model was based on Caucasian eyes that were not selected regarding refraction. The aim of this study was to determine the characteristics of the RNFB trajectories in Chinese myopic eyes. We collected high quality red free fundus images from 80 eyes of 80 Chinese myopic subjects (median [interquartile range/range] refraction -3.9 [-6.0 to -2.5/-10 to -1] D). We traced all visible RNFBs (n = 1460) and evaluated their trajectories using the previously published mathematical model. In the superior-temporal region, the RNFB trajectories of the Chinese myopic eyes were similar to that of the Caucasian eyes (86% of trajectories within the 95% central range of the Caucasian model). In the inferior-temporal region, the trajectories of the Chinese low to moderate myopic eyes were also similar to that of the Caucasian eyes (85%); trajectories of the high myopic eyes (spherical equivalent beyond -6.00 D) were clearly less curved (75%). Associations between individual deviations from the model and axial length, retinal vessel course, and optic disc anatomy were studied with multiple linear regression analysis. In the superior-temporal region, the trajectories were associated with retinal vessel course (P = 0.008) and optic disc size (P = 0.016). In the inferior-temporal region, there was a significant association with axial length (P < 0.001), retinal vessel course (P = 0.006), and disc torsion (P = 0.009).

[Perimetry in Neuro-ophthalmological Function Diagnostics: Indication - Methods - Topodiagnostic Aspects]. / Perimetrie in der neuroophthalmologischen Funktionsdiagnostik: Indikation ­ Methoden ­ Topodiagnostik.

The assessment of visual field findings is fundamental in neuro-ophthalmological functional diagnostics: By means of perimetry, functional and topodiagnostic considerations in case of unexplained visual loss or suspected lesions of the visual pathway are possible in a non-invasive manner. Repeated examinations allow for functional follow-up of a disease and judgement on the efficacy of a therapeutic procedure. This paper is intended to convey the basics of visual field examination and diagnostics. The focus is on the value of perimetry in neuro-ophthalmological functional diagnostics. Both kinetic and static perimetric methods are addressed. In addition, common examination grids and strategies, as well as interpretation of perimetric recordings and indices for the evaluation of progression analysis, are compared. Scotoma classification and the topodiagnostical relevance of visual field defects are discussed, taking into account quality parameters and plausibility controls.

Population receptive field analysis of the primary visual cortex complements perimetry in patients with homonymous visual field defects.

Injury to the primary visual cortex (V1) typically leads to loss of conscious vision in the corresponding, homonymous region of the contralateral visual hemifield (scotoma). Several studies suggest that V1 is highly plastic after injury to the visual pathways, whereas others have called this conclusion into question. We used functional magnetic resonance imaging (fMRI) to measure area V1 population receptive field (pRF) properties in five patients with partial or complete quadrantic visual field loss as a result of partial V1+ or optic radiation lesions. Comparisons were made with healthy controls deprived of visual stimulation in one quadrant ["artificial scotoma" (AS)]. We observed no large-scale changes in spared-V1 topography as the V1/V2 border remained stable, and pRF eccentricity versus cortical-distance plots were similar to those of controls. Interestingly, three observations suggest limited reorganization: (i) the distribution of pRF centers in spared-V1 was shifted slightly toward the scotoma border in 2 of 5 patients compared with AS controls; (ii) pRF size in spared-V1 was slightly increased in patients near the scotoma border; and (iii) pRF size in the contralesional hemisphere was slightly increased compared with AS controls. Importantly, pRF measurements yield information about the functional properties of spared-V1 cortex not provided by standard perimetry mapping. In three patients, spared-V1 pRF maps overlapped significantly with dense regions of the perimetric scotoma, suggesting that pRF analysis may help identify visual field locations amenable to rehabilitation. Conversely, in the remaining two patients, spared-V1 pRF maps failed to cover sighted locations in the perimetric map, indicating the existence of V1-bypassing pathways able to mediate useful vision.

SubsMatch 2.0: Scanpath comparison and classification based on subsequence frequencies.

Our eye movements are driven by a continuous trade-off between the need for detailed examination of objects of interest and the necessity to keep an overview of our surrounding. In consequence, behavioral patterns that are characteristic for our actions and their planning are typically manifested in the way we move our eyes to interact with our environment. Identifying such patterns from individual eye movement measurements is however highly challenging. In this work, we tackle the challenge of quantifying the influence of experimental factors on eye movement sequences. We introduce an algorithm for extracting sequence-sensitive features from eye movements and for the classification of eye movements based on the frequencies of small subsequences. Our approach is evaluated against the state-of-the art on a novel and a very rich collection of eye movements data derived from four experimental settings, from static viewing tasks to highly dynamic outdoor settings. Our results show that the proposed method is able to classify eye movement sequences over a variety of experimental designs. The choice of parameters is discussed in detail with special focus on highlighting different aspects of general scanpath shape. Algorithms and evaluation data are available at: http://www.ti.uni-tuebingen.de/scanpathcomparison.html .

Driving with Glaucoma: Task Performance and Gaze Movements.

PURPOSE: The aim of this pilot study was to assess the driving performance and the visual search behavior, that is, eye and head movements, of patients with glaucoma in comparison to healthy-sighted subjects during a simulated driving test. METHODS: Driving performance and gaze behavior of six glaucoma patients and eight healthy-sighted age- and sex-matched control subjects were compared in an advanced driving simulator. All subjects underwent a 40-minute driving test including nine hazardous situations on city and rural roads. Fitness to drive was assessed by a masked driving instructor according to the requirements of the official German driving test. Several driving performance measures were investigated: lane position, time to line crossing, and speed. Additionally, eye and head movements were tracked and analyzed. RESULTS: Three out of six glaucoma patients passed the driving test and their driving performance was indistinguishable from that of the control group. Patients who passed the test showed an increased visual exploration in comparison to patients who failed; that is, they showed increased number of head and gaze movements toward eccentric regions. Furthermore, patients who failed the test showed a rightward bias in average lane position, probably in an attempt to maximize the safety margin to oncoming traffic. CONCLUSIONS: Our study suggests that a considerable subgroup of subjects with binocular glaucomatous visual field loss shows a safe driving behavior in a virtual reality environment, because they adapt their viewing behavior by increasing their visual scanning. Hence, binocular visual field loss does not necessarily influence driving safety. We recommend that more individualized driving assessments, which will take into account the patient's ability to compensate, are required.

Assessing visual acuity across five disease types: ETDRS charts are faster with clinical outcome comparable to Landolt Cs.

BACKGROUND: Given the diversity of visual acuity tests being employed across the world, we compared two frequently applied tests: ETDRS charts and an eight-orientation projected Landolt C test in accordance with ISO 8596 and DIN 58220 part 3. The goals of the investigation were to determine (i) test agreement and (ii) test-retest reliability, to assess (iii) test durations, and (iv) the acceptance of the tests by the examinees as well as the subjects' coping with the tests as rated by the examiner. METHODS: Seventy-five adult subjects with a visual acuity of ≥0.2 (4/20) were included in one of the following groups: normal, media opacity, maculopathy, optic neuropathy, (post)chiasmal lesion, or amblyopia. Visual acuity testing was carried out monocularly, in balanced randomized order and in two runs for each test on the same eye, applying forced choice. RESULTS: Agreement: Within each group, all tests were performed similarly, within ±0.048 logMAR. Reliability: Across all subject groups, with a probability of 95 %, test-retest differences were <0.18 logMAR for both ETDRS and Landolt tests. DURATION: The Landolt test lasted, on average, 1.8 times longer than ETDRS charts (p < 0.001). Acceptance: Examinees preferred the ETDRS test (p < 0.001), the examiner on average had no preference. CONCLUSION: The Landolt C test and the ETDRS test yielded comparable results in visual acuity and test-retest reliability in all disease groups. The ETDRS test was usually faster and more accepted by both examiners and examinees than the Landolt test.

Assessment of functional and morphometric endpoints in patients with non-arteritic anterior ischemic optic neuropathy (NAION).

BACKGROUND: The primary objective of this bi-center explorative pilot study was the quantitative assessment of visual field defects and retinal nerve fiber layer thickness (RNFT) over 6 months in patients with acute non-arteritic anterior ischemic optic neuropathy (NAION), in order to elucidate the natural course of NAION and provide a reference dataset for future treatment studies. METHODS: 16 patients (age 41-80 years, nine males, seven females) suffering from acute NAION and presenting within 7 days after onset of symptoms were included in this study. The following examinations were carried out at the initial visit (month 0) and at months 2, 4 and 6: entire (90°) visual field examination with automated static white-on-white perimetry, quantified by mean defect (MD); peripapillary retinal nerve fiber layer thickness (RNFT) measurement with spectral domain optical coherence tomography (SD-OCT); assessment of distant best correct visual acuity (D-BCVA) and a quantification of the relative afferent pupillary defect (RAPD) using the swinging flashlight test with neutral density filters. Perimetric Mean Defect (MD) and RNFT values were each compared between the consecutive visits using the non-parametric Friedman test. RESULTS: The initial MD was 6.2 dB (IQR 5.0-7.4) without significant changes further on. RNFT was 183 µm (IQR 148-252) initially, decreased significantly at month 2 (78 µm (IQR 71-93) and further at month 4 (64 µm (IQR 58-74) and 6 (61 µm (IQR 52-81), Friedman test, p < 0.001). Initially, RNFT was above normal limits (due to swelling) in 15/16 patients; at month 2 it was below normal limits in 13/16 patients, at month 4 in 12/13 patients and at month 6 in 9/10 patients. 7/16 patients exhibited segmental swelling of the optic disc, whereas the entire circumference of the optic disc showed RNFL thickening in 9/16 patients. CONCLUSION: Functional deficits were present directly after onset of NAION and did not change relevantly further on. Morphological changes comprise severe swelling after onset of NAION, which rapidly turns into atrophy. Already after 2 months more than 80 % of the patients showed a RNFT below normal limits. Progressive RNFL thinning between month 2 and month 4 suggests ongoing atrophy, whereas a stable morphologic end point is reached after month 4.

Relationship between the area of isopters and Vigabatrin dosage during two years of observation.

BACKGROUND: The aim of the study was to evaluate the relationship between the area of isopters obtained using semi-automated kinetic perimetry (SKP) and Vigabatrin dosage in epilepsy patients with pretreatment baseline examination during 2-years of the follow-up. METHODS: 29 epilepsy patients were included into the study, but 15 individuals were excluded due to cognitive impairment, intracranial pathologies or eye diseases. Finally, 14 patients were examined with SKP before VGB treatment and after 6, 12, 18, and 24 months. Reaction time (RT)-corrected areas of three isopters (III4e, I4e and I2e) were measured for each of five examinations and compared intra-individually during 2-years period. Additionally, six epilepsy patients on other antiepileptic drugs were examined five times with SKP as a control. RESULTS: There was a significant decrease of I2e, I4e and III4e isopters' area during the follow-up of two years. Correlation was found between the I2e isopter's area and both cumulative dose and mean daily dose of VGB. With increasing RT, there was decreasing of all isopters' area in patients receiving VGB. In epilepsy patients who were not receiving VGB, there were no significance differences in isopters' area during follow-up. CONCLUSION: There was attenuation of area of III4e, I4e and I2e isopters obtained with SKP during a period of 2 years. RT, the cumulative dose and the mean daily dose of VGB influenced isopters' area obtained with SKP.

Decreased retinal sensitivity and loss of retinal nerve fibers in multiple system atrophy.

BACKGROUND AND AIM: In a previous study, retinal nerve fiber layer thickness (RNFLT) loss was shown as part of the neurodegenerative process in multiple system atrophy (MSA). Here, we investigate in a larger cohort of MSA patients whether the RNFLT loss translates into respective visual field defects. METHODS: Spectral domain optical coherence tomography was performed in 20 MSA patients (parkinsonian subtype = 12, cerebellar subtype = 8) to quantify peripapillary RNFLT. Visual field (90°) was analyzed by automated static perimetry to investigate retinal structure/function relationship. Eight data sets did not meet stringent quality criteria, and only 12 data sets were further analyzed. RESULTS: Compared to healthy controls, MSA patients demonstrated a significant reduction of RNFLT in the nasal sectors (p ( nasal-superior ) = 0.02, p ( nasal ) = 0.03, p ( nasal-inferior ) < 0.01), while changes in temporal RNFLT measures (p ( temporal-superior ) = 0.42, p ( temporal ) = 0.34, p ( temporal-inferior ) = 0.25) were not statistically significant compared to healthy controls (ANOVA). MSA patients featured a significant global mean deviation (2.74 dB; p < 0.01) without predominant peripheral visual field defects. Statistical analysis of mean defect in the central (0-30°), peripheral (30-90°) or global (0-90°) visual field revealed no significant correlation (r (2) (central) = 0.11, r (2) (peripheral) = 0.04, r (2) (global) = 0.07) with nasal RNFLT in MSA patients. CONCLUSION: MSA patients feature significant reduction in nasal RNFLT and global mean deviation when compared to healthy controls, consistent with the multi-systemic nature of this neurodegenerative disorder. This finding provides first evidence for two independent deteriorations of the visual system in MSA.

A mathematical model for describing the retinal nerve fiber bundle trajectories in the human eye: average course, variability, and influence of refraction, optic disc size and optic disc position.

Previously we developed a mathematical model for describing the retinal nerve fiber bundle trajectories in the superior-temporal and inferior-temporal regions of the human retina, based on traced trajectories extracted from fundus photographs. Aims of the current study were to (i) validate the existing model, (ii) expand the model to the entire retina and (iii) determine the influence of refraction, optic disc size and optic disc position on the trajectories. A new set of fundus photographs was collected comprising 28 eyes of 28 subjects. From these 28 photographs, 625 trajectories were extracted. Trajectories in the temporal region of the retina were compared to the existing model. In this region, 347 of 399 trajectories (87%) were within the 95% central range of the existing model. The model was extended to the nasal region. With this extension, the model can now be applied to the entire retina that corresponds to the visual field as tested with standard automated perimetry (up to approximately 30° eccentricity). There was an asymmetry between the superior and inferior hemifields and a considerable location-specific inter-subject variability. In the nasal region, we found two "singularities", located roughly at the one and five o'clock positions for the right optic disc. Here, trajectories from relatively widespread areas of the retina converge. Associations between individual deviations from the model and refraction, optic disc size and optic disc position were studied with multiple linear regression. Refraction (P = 0.021) and possibly optic disc inclination (P = 0.09) influenced the trajectories in the superior-temporal region.

Facial dysmorphopsia: a notable variant of the "thin man" phenomenon?

BACKGROUND: The aim of this work is to investigate the facial distortion (dysmorphopsia) experienced by patients with homonymous paracentral scotomas and to analyze the interrelationship with the previously described "thin man" phenomenon. METHODS: Routine neuro-ophthalmological examination and brain MRI in three patients who suffered from small homonymous paracentral scotomas due to infarction or arteriovenous malformations of the occipital lobe. They all complained of distortion and shrinkage of their interlocutor's face contralateral to the brain lesion. The phenomenon appeared some seconds after steady fixation on the interlocutor's nose and was evident with both left and right homonymous scotomas. The patients did not notice a gap in the area corresponding to the scotoma and objects other than faces were perceived normally. RESULTS: Homonymous paracentral scotomas can lead to focal displacement of facial features towards the center of the field defect with resulting distortion of the face on the affected side. This so-called "dysmorphopsia" makes faces appear regionally narrower than they are in reality and may be induced even by visual field defects that remain undetected by conventional perimetry using 6° × 6° grids. Predilection for faces is probably associated with the superior location of scotomas or specific impairment of face processing abilities related to the lesion site. CONCLUSIONS: Facial dysmorphopsia is most probably associated with cortical "filling-in" and spatial distortion, and can hence be regarded as a special entity of the "thin man" phenomenon.

Optical coherence tomography shows progressive local nerve fiber loss after disc hemorrhages in glaucoma patients.

BACKGROUND AND AIM: The aim of this work is to investigate whether optic disc hemorrhages (ODH) lead to significant loss of nerve fibers at the lesion site over time and whether such a loss is reflected by visual field defects corresponding to the affected nerve fiber bundle. METHODS: In this retrospective study of ten sequential glaucoma patients (ten eyes) with ODH, we used high-resolution OCT circular scans (Spectralis HRA + OCT, Heidelberg Engineering, Heidelberg, Germany) to determine peripapillary retinal nerve fiber layer (RNFL) thickness at the time of ODH presentation and at follow-up visit between 3 and 6 months. Corresponding perimetric data were analyzed for global (mean defect, MD) and localized progression of visual field defects. RESULTS: ODH were mostly located in the inferior quadrant as determined clinically and from fundus photographs. Iterative OCT imaging revealed a significant RNFL reduction in the affected quadrant relative to the respective quadrant in the fellow eye (RNFL change = -2.25 ± 2.69 µm vs. 0.75 ± 2.78 µm, p = 0.01) within 120 ± 43 days. However, only three cases presented with new/progressive nerve fiber bundle defects corresponding to the lesion site within the given follow-up period. CONCLUSIONS: ODH lead to a significantly higher RNFL loss at the lesion site relative to the overall structural progression in glaucoma patients. However, this focal change is not generally reflected by respective nerve fiber bundle defects in the time frame investigated.

Variability in isopter position and fatigue during semi-automated kinetic perimetry.

BACKGROUND: Assessment of factors influencing response variability to repeat presentations of III4e stimuli and the fatigue effect during semi-automated kinetic perimetry (SKP). DESIGN: Prospective case series; setting: university hospital. PARTICIPANTS: 58 patients with severe visual field loss: 21 with glaucoma, 18 with retinitis pigmentosa, and 19 with postchiasmal visual pathway lesions. METHODS: Following initial testing with three isopters (I2e or V4e, I4e and III4e), presentations of the III4e stimulus were repeated four times during the same session along identical vectors. MAIN OUTCOME MEASURES: Variability in III4e-isopter position (scatter of kinetic threshold) and the difference of isopter area between the first and four subsequent sessions (fatigue effect) of SKP were analyzed by diagnosis, age, visual acuity and reaction time (RT). RESULTS: The mean scatter of the kinetic threshold was 2.5 degrees (deg) in the glaucoma group, 1.5 deg in the group with retinitis pigmentosa, and 1.7 deg in the group of patients with postchiasmal lesions. The difference in the isopter area between a single examination and four times repeated examination was 656 square degrees (deg(2)) in the glaucoma group, 104 deg(2) in the retinitis pigmentosa group and 227 deg(2) in the group of patients with postchiasmal lesions. Post-hoc regression analysis revealed that the variability of isopter position increased as the RT increased. CONCLUSION: The variability of III4e-isopter positionand fatiguewere most pronounced among glaucoma patients. RT is the most important factor influencing the variability of responses and fatigue during SKP, thus we propose that it can be used as a reliability indicator of SKP.

Peripheral homonymous hemianopia: correlation between lesion location and visual field defects by means of cytoarchitectonic probabilistic maps.

BACKGROUND: Peripheral homonymous scotomas beyond 30° from fixation are rare. The paucity of publications describing such visual field defects might be attributed to various factors, including the absence of severe symptoms, routine visual field assessment restricted to the central 30° with automated perimetry, and the collateral circulation to the occipital cortex. The aim of this study was to correlate the brain lesions and perimetric findings in 2 unusual cases of peripheral homonymous scotomas, with the anatomic location of the optic radiation and primary visual cortex. METHODS: Two patients with circumscribed homonymous scotomas beyond 30° related to infarcts in the intermediate area of the visual cortex are reported. We describe a new strategy, which relies on modern lesion analysis and stereotaxic probabilistic cytoarchitectonic maps, to accurately correlate the brain lesion site with the location of the peripheral homonymous visual field defects. RESULTS: In Case 1, the posterior optic radiation was affected in its termination in the upper intermediate visual cortex. In Case 2, the lesion was located in the upper rostral portion of the primary visual cortex. In both, the most anterior part of the visual cortex and the occipital pole were intact, accounting for preservation of the central and most peripheral visual field. Additionally, correlation of the neuroimaging findings with commonly used maps of the representation of the visual field on the striate cortex suggested that our data were most consistent with the Holmes map. CONCLUSIONS: Modern lesion analysis and cytoarchitectonic maps, in combination with the existing retinotopic maps, may provide reliable clues for the localization of cerebral infarction and prognosis of homonymous visual field defects and may lead to a better understanding of the link between neuroanatomical landmarks and functional outcomes.

Three-Year Changes in Visual Function in the Placebo Group of a Randomized Double-Blind International Multicenter Safety Study: Analysis of Electroretinography, Perimetry, Color Vision, and Visual Acuity in Individuals With Chronic Stable Angina Pectoris.

Purpose: To determine whether significant deteriorations in objective (electroretinography [ERG]) and subjective (standard automated and semi-automated kinetic perimetry; color discrimination; and best-corrected visual acuity) tests of visual function, potentially attributable to aging, occurred in the group randomized to placebo of a 3-year prospective multicenter ocular safety study of ivabradine for chronic stable angina pectoris. Methods: The multicenter trial was conducted at 11 international ophthalmic centers. Changes in visual function between baseline and month 36 were analyzed by means of a two-tailed Wilcoxon signed-rank test, based on the Hodges and Lehman estimator of the median difference, with the 95% confidence intervals derived by Walsh averages. Results: Thirty-eight participants from the placebo group completed the study (mean [SD], age, 62.7 [8.1] years). The group exhibited in each eye small, but statistically significant, reductions in the amplitudes of the dark-adapted (DA) ERG 3.0 a-wave, and light-adapted (LA) 3.0 b-wave, as well as increases in peak time for the DA 0.01 b-wave, DA 3.0 a-wave, LA 3.0 b-wave, and LA 3.0 30-Hz flicker response and in the isopter area I3e of the visual field. Conclusions: Statistically significant deteriorations occurred in visual function over a period of 3 years, potentially attributable to age, within a group of individuals with chronic stable angina pectoris and unremarkable ophthalmological findings other than those attributable to age. Translational Relevance: A longitudinal correction factor for age-related change in visual function may be useful in future trials to determine whether an observed deterioration in visual function is related to intervention or to aging.

Contrast Sensitivity and Night Driving in Older People: Quantifying the Relationship Between Visual Acuity, Contrast Sensitivity, and Hazard Detection Distance in a Night-Time Driving Simulator.

Purpose: (i) To assess how well contrast sensitivity (CS) predicts night-time hazard detection distance (a key component of night driving ability), in normally sighted older drivers, relative to a conventional measure of high contrast visual acuity (VA); (ii) To evaluate whether CS can be accurately quantified within a night driving simulator. Materials and Methods: Participants were 15 (five female) ophthalmologically healthy adults, aged 55-81 years. CS was measured in a driving simulator using Landolt Cs, presented under static or dynamic driving conditions, and with or without glare. In the dynamic driving conditions, the participant was asked to simultaneously maintain a (virtual) speed of 60 km/h on a country road. In the with glare conditions, two calibrated LED arrays, moved by cable robots, simulated the trajectories and luminance characteristics of the (low beam) headlights of an approaching car. For comparison, CS was also measured clinically (with and without glare) using a Optovist I instrument (Vistec Inc., Olching, Germany). Visual acuity (VA) thresholds were also assessed at high and low contrast using the Freiburg Visual Acuity Test (FrACT) under photopic conditions. As a measure of driving performance, median hazard detection distance (MHDD) was computed, in meters, across three kinds of simulated obstacles of varying contrast. Results: Contrast sensitivity and low contrast VA were both significantly associated with driving performance (both P < 0.01), whereas conventional high contrast acuity was not (P = 0.10). There was good correlation (P < 0.01) between CS measured in the driving simulator and a conventional clinical instrument (Optovist I). As expected, CS was shown to decrease in the presence of glare, in dynamic driving conditions, and as a function of age (all P < 0.01). Conclusion: Contrast sensitivity and low contrast VA predict night-time hazard detection ability in a manner that conventional high contrast VA does not. Either may therefore provide a useful metric for assessing fitness to drive at night, particularly in older individuals. CS measurements can be made within a driving simulator, and the data are in good agreement with conventional clinical methods (Optovist I).

Does intraocular straylight predict night driving visual performance? Correlations between straylight levels and contrast sensitivity, halo size, and hazard recognition distance with and without glare.

Purpose: To evaluate the relationship between intraocular straylight perception and: (i) contrast sensitivity (CS), (ii) halo size, and (iii) hazard recognition distance, in the presence and absence of glare. Subjects and methods: Participants were 15 (5 female) ophthalmologically healthy adults, aged 54.6-80.6 (median: 67.2) years. Intraocular straylight (log s) was measured using a straylight meter (C-Quant; Oculus GmbH, Wetzlar, Germany). CS with glare was measured clinically using the Optovist I device (Vistec Inc., Olching, Germany) and also within a driving simulator using Landolt Cs. These were presented under both static or dynamic viewing conditions, and either with or without glare. Hazard detection distance was measured for simulated obstacles of varying contrast. For this, the participant was required to maintain a speed of 60 km/h within a custom-built nighttime driving simulator. Glare was simulated by LED arrays, moved by cable robots to mimic an oncoming car's headlights. Halo size ("halometry") was measured by moving Landolt Cs outward originating from the center of a static glare source. The outcome measure from "halometry" was the radius of the halo (angular extent, in degrees visual angle). Results: The correlation between intraocular straylight perception, log s, and hazard recognition distance under glare was poor for the low contrast obstacles (leading/subdominant eye: r = 0.27/r = 0.34). Conversely, log CS measured with glare strongly predicted hazard recognition distances under glare. This was true both when log CS was measured using a clinical device (Optovist I: r = 0.93) and within the driving simulator, under static (r = 0.69) and dynamic (r = 0.61) conditions, and also with "halometry" (r = 0.70). Glare reduced log CS and hazard recognition distance for almost all visual function parameters. Conclusion: Intraocular straylight was a poor predictor of visual function and driving performance within this experiment. Conversely, CS was a strong predictor of both hazard recognition and halo extent. The presence of glare and motion lead to a degradation of CS in a driving simulator. Future studies are necessary to evaluate the effectiveness of all above-mentioned vision-related parameters for predicting fitness to drive under real-life conditions.