Kinetic Perimetry Research Articles

Monitoring the visual field of a patient with secondary pseudotumour cerebri syndrome due to one-sided lymphadenectomy and internal jugular vein ligature — case report

We describe a case of a 37-year-old man who developed prolonged papilledema as a result of increased intracranial pressure following unilateral radical neck dissection due to diffuse large B-cell non-Hodgkin lymphoma. It seems that the increase in intracranial pressure was a result of insufficient collateral venous drainage of the brain. Clinical examination showed bilateral papilloedema, diplopia, and visual deterioration in the left eye. Magnetic resonance imaging and computed tomography of the brain were normal. Semi-automated kinetic perimetry was used to mo­nitor the visual function during 12 months of the follow-up. This method revealed enlargement of the blind spot in the left eye without progression. Peripheral borders of the visual field were within normal limits.

Vision after trans-sylvian or temporobasal selective amygdalohippocampectomy: a prospective randomised trial.

Selective amygdalohippocampectomy (SAH) is an accepted surgical procedure for treatment of pharmacoresistant mesial temporal lobe epilepsy, but it may lead to postoperative visual field deficits (VFDs). Here we present a prospective randomised trial comparing the postoperative VFDs after either a trans-sylvian or temporobasal approach for SAH. Forty-eight patients were randomly assigned to trans-sylvian (n = 24) or temporobasal (n = 24) SAH. Postoperative VFD were quantitatively evaluated using automated static and kinetic perimetry. In 24 cases, diffusion tensor imaging-based deterministic fibre-tracking of the optic radiation was performed. The primary endpoint was absence of postoperative VFD. The secondary endpoint was seizure outcome and driving ability. Three patients (13%) from the trans-sylvian group showed no VFD, compared to 11 patients (46%) from the temporobasal group without VFD (p = 0.01, RR = 3.7; CI = 1.2-11.5). Fifteen patients from each group (63%) became completely seizure-free (ILAE1). Among those seizure-free cases, five trans-sylvian (33%) and ten temporobasal (66%) patients could apply for a driving licence (NNT = 3) when VFDs were considered. Although the trans-sylvian group experienced more frequent VFDs, the mean functional visual impairment showed a tendency to be less pronounced compared with the temporobasal group. DTI-based tracking of the optic radiation revealed that a lower distance of optic radiation to the temporal base correlated with increased rate of VFD in the temporobasal group. Temporobasal SAH shows significantly fewer VFDs and equal seizure-free rate compared with the trans-sylvian SAH. However, in patients in whom the optic radiation is close to the temporal base, the trans-sylvian approach may be a preferred alternative.

The Effect of Multispot Laser Panretinal Photocoagulation on Retinal Sensitivity and Driving Eligibility in Patients With Diabetic Retinopathy.

Panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR) may lead to peripheral field loss that prevents driving. Anti-vascular endothelial growth factor agents are proposed as treatments for PDR that spare peripheral vision. If multispot lasers cause less visual field loss, continuing to perform PRP may be justified. To assess the effect of bilateral multispot laser PRP on retinal sensitivity and driving visual fields in PDR. This prospective nonrandomized interventional cohort analysis performed at a tertiary referral center included 43 laser-naive patients with PDR that required bilateral PRP. Participants were recruited from June 27, 2012, to October 14, 2013. At baseline and 6-month follow-up, patients underwent detailed static and kinetic perimetry, microperimetry, optical coherence tomography, wide-field color fundus photography, and fluorescein angiography. Quantitative change in retinal sensitivity was assessed by comparing the mean global retinal sensitivity before and after laser treatment and by comparing the modeled hill of vision by deriving a volumetric measure. Final follow-up was completed on May 21, 2014. Multispot laser treatment was applied using standard parameters, until neovascularization regressed or complete retinal coverage was achieved. Participants who passed the Esterman binocular visual field test for driving in the United Kingdom (at least 120° horizontal field with no significant defects within the central 20°) and full-field and macular retinal sensitivity. Of the 43 patients (17 men; 26 women; mean [SD] age, 46.6 [13.3] years), 38 (88%) completed the study. Before treatment, 41 of 43 patients (95%) passed the Esterman visual field test for driving; after completion of laser treatment, 35 of 38 patients (92%) passed. The mean (SD) change in retinal sensitivity on static perimetry was -1.4 (3.7) (95% CI, -2.7 to -0.1) dB OD and -2.4 (2.9) (95% CI, -3.4 to -1.4) dB OS. Mean (SD) 4° macular sensitivity decreased by 3.0 (5.2) dB OD and 2.6 (5.4) dB OS. This prospective study investigating the effects of multispot laser PRP on retinal sensitivity demonstrates a high likelihood of retaining eligibility to drive based on adequate visual field. A mild loss of retinal sensitivity was detected at 6 months after completion of laser treatment. Further change to visual fields may have occurred with longer follow-up. This study provides information that might be used to counsel patients requiring PRP and informs the debate regarding the role of anti-vascular endothelial growth factor therapy in patients with PDR who might otherwise receive laser treatment.

CR-18A REVIEW OF VISUAL OUTCOMES IN CHILDHOOD CRANIOPHARYNGIOMA TREATED WITH A HYPOTHALAMIC SPARING, SURGICAL AND RADIATION STRATEGY

CR-18. A REVIEW OF VISUAL OUTCOMES IN CHILDHOOD CRANIOPHARYNGIOMA TREATED WITH A HYPOTHALAMIC SPARING, SURGICAL AND RADIATION STRATEGY Victoria Smith1, Bronwen Walters1, Alki Liasis1, Kristian Acquilina1, Helen Spoudeas1, Katrina Prise1, Christos Moraitis1, and Richard Bowman1,2; Great Ormond Street Hospital, London, UK; UCL Institute of Child Health, London, UK AIM: To review visual outcomes in childhood craniopharyngioma. METHOD: Retrospective longitudinal case review. RESULTS: 27 (19M) patients diagnosed at mean age 88 months and followed for 26 months. VISUAL ACUITY: At first assessment 2 patients were classified as blind, (light perception & 1.325) and one having low vision (limited following) employing the WHO classification (binocular vision). Post-intervention one patient remained blind (no light perception) and 2 had low vision (1.10, 0.60). A further 6 patients had monocular vision loss (worse than 1.30) at presentation versus 7 post-intervention. Older children tended to have better visual acuity pre and post treatment (p 1⁄4 0.05). 20 (74%) patients retained final binocular vision of 0.20 LogMAR or better. VISUAL FIELDS: 9 children underwent Goldmann kinetic perimetry in at least one eye (17 eyes) graded by Wall and George classification. At diagnosis 6 (36%) eyes had minimal or mild loss, 9 eyes (53%) had moderate loss and 2 eyes (11%) had marked loss. Post-intervention 3 (17%) eyes showed no visual field loss, 6 (36%) eyes had minimal or mild loss and 8 (47%) eyes showed moderate loss. Grades improved/ were stable in 15 eyes (89%) and deteriorated in 2 (11%). OPTIC ATROPHY: Optic disc pallor was similar between first and last visit, 56% versus 50%. CONCLUSIONS: Although visual field loss and optic pallor are common most children retain good vision in at least one eye and where formal testing was possible, field deficits improved/ stabilised in most eyes (15/17). Neuro-Oncology 18:iii18–iii23, 2016. doi:10.1093/neuonc/now068.18 #The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Results at 2 Years after Gene Therapy for RPE65-Deficient Leber Congenital Amaurosis and Severe Early-Childhood–Onset Retinal Dystrophy

To provide an initial assessment of the safety of a recombinant adeno-associated virus vector expressing RPE65 (rAAV2-CB-hRPE65) in adults and children with retinal degeneration caused by RPE65 mutations. Nonrandomized, multicenter clinical trial. Eight adults and 4 children, 6 to 39 years of age, with Leber congenital amaurosis (LCA) or severe early-childhood-onset retinal degeneration (SECORD). Patients received a subretinal injection of rAAV2-CB-hRPE65 in the poorer-seeing eye, at either of 2 dose levels, and were followed up for 2 years after treatment. The primary safety measures were ocular and nonocular adverse events. Exploratory efficacy measures included changes in best-corrected visual acuity (BCVA), static perimetry central 30° visual field hill of vision (V30) and total visual field hill of vision (VTOT), kinetic perimetry visual field area, and responses to a quality-of-life questionnaire. All patients tolerated subretinal injections and there were no treatment-related serious adverse events. Common adverse events were those associated with the surgical procedure and included subconjunctival hemorrhage in 8 patients and ocular hyperemia in 5 patients. In the treated eye, BCVA increased in 5 patients, V30 increased in 6 patients, VTOT increased in 5 patients, and kinetic visual field area improved in 3 patients. One subject showed a decrease in BCVA and 2 patients showed a decrease in kinetic visual field area. Treatment with rAAV2-CB-hRPE65 was not associated with serious adverse events, and improvement in 1 or more measures of visual function was observed in 9 of 12 patients. The greatest improvements in visual acuity were observed in younger patients with better baseline visual acuity. Evaluation of more patients and a longer duration of follow-up will be needed to determine the rate of uncommon or rare side effects or safety concerns.

Modeling normative kinetic perimetry isopters using mixed-effects quantile regression.

Kinetic perimetry is used to quantify visual field size/sensitivity. Clinically, perimetry can be used to diagnose and monitor ophthalmic and neuro-ophthalmic disease. Normative data are integral to the interpretation of these findings. However, there are few computational developments that allow clinicians to collect and analyze normative data from kinetic perimeters. In this article we describe an approach to fitting kinetic responses using linear quantile mixed models. Analogously to traditional linear mixed-effects models for the mean, linear quantile mixed models account for repeated measurements taken from the same individual, but differently from linear mixed-effects models, they are more flexible as they require weaker distributional assumptions and allow for quantile-specific inference. Our approach improves on parametric alternatives based on normal assumptions. We introduce the R package kineticF, a freely available and open-access resource for the analysis of perimetry data. Our proposed approach can be used to analyze normative data from further studies.

Normal Values for the Full Visual Field, Corrected for Age- and Reaction Time, Using Semiautomated Kinetic Testing on the Octopus 900 Perimeter.

PurposeTo determine normal values of the visual field (VF), corrected for age and reaction time (RT) for semiautomated kinetic perimetry (SKP) on the Octopus 900 perimeter, create a model describing the age-dependency of these values, and assess test–retest reliability for each isopter.MethodsEighty-six eyes of 86 ophthalmologically healthy subjects (age 11–79 years, 34 males, 52 females) underwent full-field kinetic perimetry with the Octopus 900 instrument. Stimulus size, luminance, velocity, meridional angle, subject age, and their interactions, were used to create a smooth multiple regression mathematical model (V/4e, III/4e, I/4e, I/3e, I/2e, I/1e, and I/1a isopters). Fourteen subjects (2 from each of 7 age groups) were evaluated on three separate sessions to assess test–retest reliability of the isopters. Reaction time (RT) was tested by presenting 12 designated RT-vectors between 10° and 20° within the seeing areas for the III/4e isopter (stimulus velocity, 3°/second). Four RT- vectors were presented at the nasal (0° or 180°), superotemporal (45°), and inferior (270°) meridians.ResultsThe model fit was excellent (r2 = 0.94). The test–retest variability was less than 5°, and the median decrease in this deviation attributed to aging, per decade, for all age groups and for all stimulus sizes was 0.8°. No significant learning effect was observed for any age group or isopter.ConclusionAge-corrected and RT-corrected normative threshold values for full-field kinetic perimetry can be adequately described by a smooth multiple linear regression mathematical model.Translational RelevanceA description of the entire kinetic VF is useful for assessing a full characterization of VF sensitivity, determining function losses associated with ocular and neurologic diseases, and for providing a more comprehensive analysis of structure–function relationships.

Photopsia and a temporal visual field defect

A 30-year-old woman presented with intermittent photopsia, a temporal visual field defect below the horizontal in her left eye, and flu-like symptoms. Slit-lamp and fundus examinations were unremarkable. Humphrey 30-2 threshold perimetry and 120-point screening visual field demonstrated blind spot enlargement of the left eye and a normal field in the right eye. Fundus autofluorescence, optical coherence tomography of the macula, full-field electroretinogram, electrooculogram, and multifocal electroretinogram were normal. Swept-source optical coherence tomography scan of the left optic nerve showed an intact outer retina, a remarkably thinned nerve fiber layer nasally, and peripapillary vitreous traction. Goldmann kinetic perimetry revealed a sector-shaped dense defect breaking out from the blind spot to the temporal periphery just below the horizontal in the left eye. The patient had nasal hypoplasia of the optic nerve and peripapillary vitreous traction.

Quantification of the Visual Field Loss in Retinitis Pigmentosa Using Semi-Automated Kinetic Perimetry

ABSTRACT Purpose: To assess quantitatively the natural course of the visual field (VF) loss in patients with retinitis pigmentosa (RP) during 2-year period of observation. Methods: VFs were obtained by semi-automated kinetic perimetry (SKP) during four examinations of 16 patients suffering from RP. Three stimulus conditions (V4e, III4e and I4e) with a constant stimulus angular velocity of 3°/s were used to assess the hill of vision in both eyes of each patient. The area of each isopter was measured in square degrees and corrected for the individual reaction time (RT). Results: There were four patients with mild restriction of VF, six with ring scotomas and six with advanced concentric constrictions of VF. Only I4e isopter area decreased significantly from the first to the last session (p = 0.006), the difference was 154 deg2 being 13% of initial isopter area. The difference was not significant for V4e and III4e isopters. RT values did not differ significantly between four sessions. Conclusions: Only I4e isopter’s area was decreased significantly during two years of observation. SKP provides a method of assessment of progression of the VF loss in patients suffering from RP by measurement of the isopters’ area over time.

Apparent Contradictions in Pupillomotor, Sensory Visual and Electrodiagnostic Findings in Chiasmal Compression

PurposeTo improve the understanding of pupillomotor and electrodiagnostic findings in correlation to visual sensory defects in chiasmal compression.MethodsFull and half field VEPs were recorded by the Roland Retiport system. Stato‐kinetic dissociation in visual field findings was demonstrated by Goldmann kinetic and Twinfield static perimetry. Low luminance conditions are applied with both kinetic and static perimetry. In addition, the he swinging flashlight pupil test was applied in different variants, to solve apparent contradictions in functional findings. Analyzed are two cases of chiasmal compression by aneurysms of the internal carotid artery and one case of a tuberculum sellae meningeoma, in which visual symptoms were the presenting ones.ResultsDespite sensory symptoms may be confined to one eye, contralateral involvement due to chiasmal compression may show up in perimetry – more early by static than by kinetic examination. Low luminance perimetry produces more significant field defects in chiasmal lesins than standard perimetry. The swinging flash comparison of pupil responses may miss the unilateral relative afferent defect, depending on the direction of the light stimulus. Comparing not only responses to OD and to OS stimulation but also pupil responses to upper and lower half field stimulation helps to not overlook relative afferent pupil defects. Comparing, on the other hand, upper and lower half field VEPs has to consider physiological differences in these responses.ConclusionsIn chiasmal compression, apparent contradictions in results of functional examinations may lead to false diagnostic conclusions or even to doubts concerning the somatic origin of visual complaints. The above mentioned extended toolbox of functional exams improves the diagnostic reliability.

Molecular Heterogeneity Within the Clinical Diagnosis of Pericentral Retinal Degeneration.

To characterize in detail the phenotype and genotype of patients with pericentral retinal degeneration (PRD). Patients were screened for an annular ring scotoma ranging from 3° to 40° (n = 28, ages 24-71) with kinetic perimetry. All patients had pigmentary retinopathy in the region of the dysfunction. Further studies included cross-sectional and en face imaging, static chromatic perimetry, and electroretinography. Molecular screening was performed. Genotypes of 14 of 28 PRD patients were identified: There were mutations in eight different genes previously associated with autosomal dominant or autosomal recessive RDs. Kinetic fields monitored in some patients over years to more than a decade could be stable or show increased extent of the scotoma. Electroretinograms were recordable but with different severities of dysfunction. Patterns of photoreceptor outer nuclear layer (ONL) loss corresponded to the distribution of visual dysfunction. Outer nuclear layer thickness topography and en face imaging indicated that the greatest disease expression was in the area of known highest rod photoreceptor density. Molecular heterogeneity was a feature of the PRD phenotype. Many of the molecular causes were also associated with other phenotypes, such as maculopathies, typical retinitis pigmentosa (RP) and cone-rod dystrophy. The pericentral pattern of retinal degeneration is thus confirmed to be an uncommon phenotype of many different genotypes rather than a distinct disease entity.

How to interpret visual fields

Imagine you are assessing a patient with visual difficulties or optic disc swelling. After a bedside visual field examination with waggling fingers and even a red hatpin, you decide that...

Study of Optimal Perimetric Testing In Children (OPTIC): Normative Visual Field Values in Children

We sought to define normative visual field (VF) values for children using common clinical test protocols for kinetic and static perimetry. Prospective, observational study. We recruited 154 children aged 5 to 15 years without any ophthalmic condition that would affect the VF (controls) from pediatric clinics at Moorfields Eye Hospital. Children performed perimetric assessments in a randomized order using Goldmann and Octopus kinetic perimetry, and Humphrey static perimetry (Swedish Interactive Thresholding Algorithm [SITA] 24-2 FAST), in a single sitting, using standardized clinical protocols, with assessment by a single examiner. Unreliable results (assessed qualitatively) were excluded from the normative data analysis. Linear, piecewise, and quantile mixed-effects regression models were used. We developed a method to display age-specific normative isopters graphically on a VF plot to aid interpretation. Summary measures and graphical plots describing normative VF data for 3 common perimetric tests. Visual field area increased with age on testing with Goldmann isopters III4e, I4e, and I2e (linear regression; P < 0.001) and for Octopus isopters III4e and I4e (linear regression; P < 0.005). Visual field development occurs predominately in the inferotemporal field. Humphrey mean deviation (MD) showed an increase of 0.3 decibels (dB; 95% CI, 0.21-0.40) MD per year up to 12 years of age, when adult MD values were reached and thereafter maintained. Visual field size and sensitivity increase with age in patterns that are specific to the perimetric approach used. These developmental changes should be accounted for when interpreting perimetric test results in children, particularly when monitoring change over time.

Effects of mydriasis and miosis on kinetic perimetry findings in normal participants.

To evaluate the effects of pharmacologically induced mydriasis and miosis on kinetic perimetry findings in normal participants. Thirty-eight eyes of 38 healthy young participants underwent kinetic perimetry (Octopus 900 perimeter) with III4e, I4e, I3e, I2e, and I1e stimuli. For each participant, 24 predetermined meridians with 15° intervals were automatically tested with a velocity of 3°/s under normal, mydriatic, and miotic conditions. Mydriasis and miosis were induced by one drop of 0.4 % tropicamide and 2 % pilocarpine hydrochloride, respectively. The isopter area and kinetic sensitivity were compared between the three pupil conditions. The average pupil size in the normal condition was 5.6 ± 0.9 mm, and it significantly increased to 8.5 ± 0.7 mm after mydriasis (p < 0.01) and decreased to 3.4 ± 0.8 mm after miosis (p < 0.01). Compared to the normal pupil, the isopter area of the dilated pupil was not significantly different under the III4e stimulus; however, it significantly decreased under the I4e, I3e, I2e, and I1e stimuli (p < 0.01). Compared to the normal pupil, the isopter area of the constricted pupil significantly decreased (p < 0.01) with the III4e stimulus and significantly increased with the I3e and I2e stimuli (p < 0.05). For both pupil conditions, kinetic sensitivity at each meridian showed a similar trend to the isopter area under each stimulus. The isopter area of the dilated pupil generally decreased, whereas the isopter area of the constricted pupil showed various findings. Therefore, careful attention should be paid to changes in the isopter area associated with changes in the pupil size.

Effects of different levels of intraocular stray light on kinetic perimetry findings.

PurposeTo evaluate the effect of different levels of intraocular stray light on kinetic perimetry findings.MethodsTwenty-five eyes of 25 healthy young participants were examined by automated kinetic perimetry (Octopus 900) using Goldmann stimuli III4e, I4e, I3e, I2e, and I1e. Each stimulus was presented with a velocity of 3°/s at 24 meridians with 15° intervals. Four levels of intraocular stray light were induced using non-white opacity filter (WOF) filters and WOFs applied to the clear plastic eye covers of the participants. The visual acuity, pupil diameter, isopter area, and kinetic sensitivity of each meridian were analyzed for each WOF density.ResultsVisual acuity deteriorated with increasing WOF densities (p < 0.01). With a visual acuity of 0.1 LogMAR units, the isopter areas for III4e, I4e, I3e, I2e, and I1e decreased by -32.7 degree2 (-0.2%), -255.7 degree2 (-2.6%), -381.2 degree2 (-6.2%), -314.8 degree2 (-12.8%), and -59.2 degree2 (-15.2%), respectively; kinetic sensitivity for those stimuli decreased by -0.1 degree (-0.1%), -0.8 degree (-1.4%), -1.6 degree (-3.7%), -2.7 degree (-9.7%), and -1.7 degree (-16.2%), respectively. The pupil diameter with each WOF density was not significantly different.ConclusionKinetic perimetry measurements with a high-intensity stimulus (i.e., III4e) were unaffected by intraocular stray light. In contrast, measurements with the I4e, I3e, I2e, and I1e stimuli, especially I2e and I1e, were affected. Changes in the shape of the isopter resulting from opacity must be monitored, especially in cases of smaller and lower-intensity stimuli.

Detection of Visual Field Loss in Pituitary Disease: Peripheral Kinetic Versus Central Static

Visual field assessment is an important clinical evaluation for eye disease and neurological injury. We evaluated Octopus semi-automated kinetic peripheral perimetry (SKP) and Humphrey static automated central perimetry for detection of neurological visual field loss in patients with pituitary disease. We carried out a prospective cross-sectional diagnostic accuracy study comparing Humphrey central 30-2 SITA threshold programme with a screening protocol for SKP on Octopus perimetry. Humphrey 24-2 data were extracted from 30-2 results. Results were independently graded for presence/absence of field defect plus severity of defect. Fifty patients (100 eyes) were recruited (25 males and 25 females), with mean age of 52.4 years (SD = 15.7). Order of perimeter assessment (Humphrey/Octopus first) and order of eye tested (right/left first) were randomised. The 30-2 programme detected visual field loss in 85%, the 24-2 programme in 80%, and the Octopus combined kinetic/static strategy in 100% of eyes. Peripheral visual field loss was missed by central threshold assessment. Qualitative comparison of type of visual field defect demonstrated a match between Humphrey and Octopus results in 58%, with a match for severity of defect in 50%. Tests duration was 9.34 minutes (SD = 2.02) for Humphrey 30-2 versus 10.79 minutes (SD = 4.06) for Octopus perimetry. Octopus semi-automated kinetic perimetry was found to be superior to central static testing for detection of pituitary disease-related visual field loss. Where reliant on Humphrey central static perimetry, the 30-2 programme is recommended over the 24-2 programme. Where kinetic perimetry is available, this is preferable to central static programmes for increased detection of peripheral visual field loss.

Blue cone monochromacy: visual function and efficacy outcome measures for clinical trials.

BackgroundBlue Cone Monochromacy (BCM) is an X-linked retinopathy caused by mutations in the OPN1LW / OPN1MW gene cluster, encoding long (L)- and middle (M)-wavelength sensitive cone opsins. Recent evidence shows sufficient structural integrity of cone photoreceptors in BCM to warrant consideration of a gene therapy approach to the disease. In the present study, the vision in BCM is examined, specifically seeking clinically-feasible outcomes for a future clinical trial.MethodsBCM patients (n = 25, ages 5–72) were studied with kinetic and static chromatic perimetry, full-field sensitivity testing, and eye movement recordings. Vision at the fovea and parafovea was probed with chromatic microperimetry.ResultsKinetic fields with a Goldmann size V target were generally full. Short-wavelength (S-) sensitive cone function was normal or near normal in most patients. Light-adapted perimetry results on conventional background lights were abnormally reduced; 600-nm stimuli were seen by rods whereas white stimuli were seen by both rods and S-cones. Under dark-adapted conditions, 500-nm stimuli were seen by rods in both BCM and normals. Spectral sensitivity functions in the superior retina showed retained rod and S-cone functions in BCM under dark-adapted and light-adapted conditions. In the fovea, normal subjects showed L/M-cone mediation using a 650-nm stimulus under dark-adapted conditions, whereas BCM patients had reduced sensitivity driven by rod vision. Full-field red stimuli on bright blue backgrounds were seen by L/M-cones in normal subjects whereas BCM patients had abnormally reduced and rod-mediated sensitivities. Fixation location could vary from fovea to parafovea. Chromatic microperimetry demonstrated a large loss of sensitivity to red stimuli presented on a cyan adapting background at the anatomical fovea and surrounding parafovea.ConclusionsBCM rods continue to signal vision under conditions normally associated with daylight vision. Localized and retina-wide outcome measures were examined to evaluate possible improvement of L/M-cone-based vision in a clinical trial.

Disturbed temporal dynamics of brain synchronization in vision loss

Damage along the visual pathway prevents bottom-up visual input from reaching further processing stages and consequently leads to loss of vision. But perception is not a simple bottom-up process – rather it emerges from activity of widespread cortical networks which coordinate visual processing in space and time. Here we set out to study how vision loss affects activity of brain visual networks and how networks' activity is related to perception. Specifically, we focused on studying temporal patterns of brain activity. To this end, resting-state eyes-closed EEG was recorded from partially blind patients suffering from chronic retina and/or optic-nerve damage (n = 19) and healthy controls (n = 13). Amplitude (power) of oscillatory activity and phase locking value (PLV) were used as measures of local and distant synchronization, respectively. Synchronization time series were created for the low- (7–9 Hz) and high-alpha band (11–13 Hz) and analyzed with three measures of temporal patterns: (i) length of synchronized-/desynchronized-periods, (ii) Higuchi Fractal Dimension (HFD), and (iii) Detrended Fluctuation Analysis (DFA). We revealed that patients exhibit less complex, more random and noise-like temporal dynamics of high-alpha band activity. More random temporal patterns were associated with worse performance in static (r = −.54, p = .017) and kinetic perimetry (r = .47, p = .041). We conclude that disturbed temporal patterns of neural synchronization in vision loss patients indicate disrupted communication within brain visual networks caused by prolonged deafferentation. We propose that because the state of brain networks is essential for normal perception, impaired brain synchronization in patients with vision loss might aggravate the functional consequences of reduced visual input.

Development of a new fully automated kinetic algorithm (program k) for detection of glaucomatous visual field loss.

In Program K, a new automated kinetic algorithm that we developed, the frequency distributions of the number of patients' response points were obtained for external angles to distinguish normal and abnormal isopters. We also assessed the agreement between the results of Program K and Goldmann manual kinetic perimetry (MKP). Program K detected abnormalities in isopters by using the external angles of patients' response points. In experiment 1, a normal external angle range and endpoint for the algorithm were determined by using visual field (VF) results of 100 data sets. In experiment 2, the results of Program K and Goldmann MKP were compared in 63 virtual patients. Visual field loss was assessed by using stimuli of V/4e, III/4e, I/4e, I/3e, I/2e, and I/1e at a speed of 3 deg/s. The isopters by Program K and Goldmann MKP were overlapped and the area of intersection was expressed as a percentage of the union area. The intersection percentages and test durations were evaluated. A normal external angle range between 150° and 240° and phase 3 as the appropriate endpoint for the algorithm were determined. The intersection percentages for the six isopters were 84% (V/4e), 83% (III/4e), 78% (I/4e), 71% (I/3e), 60% (I/2e), and 50% (I/1e) (average, 71%). The average examination duration for Program K was 16.0 ± 3.2 minutes. The results of Program K and Goldmann MKP were comparable. Program K is clinically efficient and useful for detection and evaluation of abnormalities in a kinetic VF.

Extreme Thinning or Loss of Inner Neural Retina Along the Staphyloma Edge in Eyes With Pathologic Myopia

To investigate the morphologic changes along the edge of posterior staphyloma in highly myopic eyes with patchy chorioretinal atrophy and to identify the relationship between retinal thinning and the visual field (VF) defects found in these eyes. Retrospective, observational case series. Twenty eyes (17 patients) with pathologic myopia (myopic refractive error ≥ 8 diopters or an axial length ≥ 26.5mm) and patchy atrophy along the staphyloma edge were analyzed retrospectively. The VFs were obtained by Goldmann kinetic perimetry. In the area of patchy atrophy, the inner retinal tissue was very thin or completely absent. Any remnants of the retinal tissue appeared to be adherent to the layer of large choroidal vessels or to the sclera. The mean thickness of the retina at its thinnest point in the area was 51.6 ± 29.0μm in 20 eyes. The retina was thinner than 50μm at its thinnest point in 12 (60.0%) of the 20 eyes, and the mean retinal thickness at its thinnest point in these 12 eyes was 32.1 ± 16.0μm (range, 4 to 49μm). Nineteen eyes (VF of 1 eye was not determined) had very similar VF findings by Goldmann perimetry, that is, a defect of the sector corresponding to the course of retinal nerve fiber over the patchy atrophy. The results show that the thickness of not only the outer retina, but also of most of the inner retina, including the nerve fiber layer, is significantly thinner at the staphyloma edge. Such damage to the inner retina along the staphyloma edge causes the VF defects in highly myopic eyes.