Scotoma

PURPOSE. To correlate the dimension of the visual field (VF) tested by Goldman kinetic perimetry with the extent of visi- bility of the highly reflective layer between inner and outer segments of photoreceptors (IOS) seen in optical coherence tomography (OCT) images in patients with retinitis pigmen- tosa (RP). METHODS. In a retrospectively designed cross-sectional study, 18 eyes of 18 patients

A technique for accurate superimposition of computerized perimetry data onto the corresponding retinal locations seen on fundus photographs was developed. The technique was designed to take into account: 1) that the photographic field of view of the fundus camera varies with ametropia-dependent camera focusing 2) possible distortion by the fundus camera, and 3) that corrective lenses employed during perimetry magnify or minify the visual field. The technique allowed an overlay of perimetry data of the central 60 degrees of the visual field onto fundus photographs with an accuracy of 0.5 degree. The correlation of localized retinal morphology to localized retinal function was therefore limited by the spatial resolution of the computerized perimetry, which was 2.5 degrees in the Dicon AP-2500 perimeter employed for this study. The theoretical assumptions of the technique were confirmed by comparing visual field records to fundus photographs from patients with morphologically well-defined non-functioning lesions in the retina.

Brain neuronal dysfunction has been implicated in pathogenesis of migraine but direct evidence is lacking. Scintillating scotoma of migraine is generally believed to originate at the visual cortex. While cortical spreading depression is a relatively late physiological alteration in migraine, its protective role in neuronal ischaemia is increasingly being recognized. Atenolol, nadolol, or verapamil prevent migraine but do not readily cross the blood–brain barrier or critically influence any brain or peripheral neuronal function. Typical migraine headache, aura, or scintillating scotoma has not been reported following enucleation or evisceration of the eye. In humans, pain and temperature fibres from only the ophthalmic division of the trigeminal nerve reach the upper cervical spinal segments. Pain in migraine attacks including occipital and nuchal discomfort reflects selective involvement of the ophthalmic nerve. Photophobia is largely a retinal reflex involving the ophthalmic division of the trigeminal nerve. Key clinical features of the migrainous scintillating scotoma are consistent with retinal origin. Spreading depression in the retina is well-established. A subtle regional ocular sympathetic deficit prevails in migraine patients and possibly impairs regulation of intraocular choroidal blood volume and intraocular pressure. Several first-line migraine prophylactic agents lower the intraocular pressure. The neuro-ophthalmological basis for a monocular origin of migrainous scintillating scotomata due to mechanical deformation of the posterior segment of the corneo-scleral envelope consequent to choroidal venous congestion and rise in intraocular pressure is presented. Study of distribution and displaceability of the migrainous scintillating scotoma can settle its site of origin. Headache of migraine possibly arises from a similar mechanical deformation of the anterior eye segment followed by antidromic discharge in the trigeminovascular system. Lateralizing negative deficits such as homonymous hemianopia probably reflect vasospastic complications of migraine. A rational explanation for the most characteristic clinical features of migraine and a new template to elucidate the pharmacological basis of anti-migraine drugs is offered.

To investigate whether the positive prism test response is due to the presence of a suppression scotoma or the absence of bifoveolar fixation. Fifty-one subjects with esotropia (microtropia, small-, moderate- or large-angle esotropia), and 22 subjects with nonstrabismic anisometropic amblyopia were examined. The prism test was performed by using base-out prisms of two different powers (4-PD and 30-PD), and base-in prism of 20-PD, as well as base-down prism of 10-PD for each subject. All the subjects with esotropia showed a positive prism test response, whereas all the subjects with nonstrabismic anisometropic amblyopia had a negative prism test response. All the esotropic subjects showed positive response to all magnitudes and positions of the prisms tested. The positive response to the prism test does not indicate suppression scotoma in subjects with microtropia and small-angle esotropia because all the esotropic subjects showed the positive response regardless of the amount of deviation or the sensorial adaptation mechanisms. Also, the positive response, seen in the esotropic subjects, did not alter to negative by using the prisms of different powers and directions.

ABSTRACT
The TV series Our Boys (2019), which deals with traumatic historical
events, provides the basis for a discussion of blind spots (scotoma) as
a metaphor for collective denial. This social blindness is one of the
troubling phenomena of the current sociopolitical and cultural period
and bears in particular on the erasure in public consciousness of
moral infractions and processes of dehumanization. While myths,
legends, and stories have always been a means to represent social
processes, and a space to reflect on them, today digital media and TV
series in particular tell the unifying stories of the age. The article aims
to derive further knowledge about how denial and scotoma work in
society and explore how a TV series can point towards a remedy. To
this end, it focuses on locating and naming the medium’s methods
which allow this phenomenon to be represented and worked
through. The article shows how from episode to episode, Our Boys’
narrative structure, points of view, mise en scène and editing permit
a wider visual range. Expansion of the viewer’s visual field prompts
this process of working through, initiating a movement from denial
to taking responsibility for establishing a moral sociality.

To test the ability of a new type of multifocal objective perimetry to identify glaucomatous visual field defects. A multichannel visual evoked potential was recorded using the ObjectiVision Accumap perimeter. One hundred patients (age, 62.2 +/- 9.8 years, mean MD -6.5 +/- 4.17 dB) with open-angle glaucoma and confirmed glaucomatous visual field defects were tested and compared with the normal database of 100 normal subjects (age, 58.9 +/- 10.7 years). Both eyes were tested, but for determining sensitivity the eye with the lesser field defect was chosen if both qualified. The amplitude and intereye asymmetry coefficient for each zone of the field were calculated. A mean amplitude and multifocal objective perimetry severity index was calculated for each subject. In 95 of 100 (95%) patients with glaucoma Humphrey field defects were correlated with visual evoked potential amplitude reductions identifying a cluster of three or more abnormal zones. In two of five remaining patients with glaucoma the defect was detected on the intereye asymmetry analysis. Topographic location was well correlated with Humphrey fields. Mean amplitude was significantly reduced in 86 of the glaucoma cases (86%). The glaucoma severity index was abnormal in 93 glaucoma cases and showed a correlation with Humphrey MD (r = 0.67 right eyes, 0.69 left eyes). In 37 glaucoma cases with no scotoma by definition in the fellow eye, 22 (59.4%) had an abnormal multifocal objective perimetry, whereas only eight had some other aspect of their Humphrey visual field flagged as abnormal. Multifocal objective perimetry can assess the visual field and identify glaucomatous visual field defects. It may have the potential for identifying defects earlier than conventional perimetry.

To investigate whether the presence of silent cerebral infarct (SCI) is related to field progression in patients with newly diagnosed normal-tension glaucoma (NTG). Prospective cohort study. A total of 286 eyes from 286 NTG patients: 64 with SCI (SCI+) and 222 without SCI (SCI-). Patients were assigned to the SCI+ or SCI- group depending on the presence of SCI as detected by cranial computed tomography scan at baseline. Patients were followed-up at 4-month intervals for 36 months for visual field progression as per Anderson's criteria. The primary outcome was the association between SCI and field progression. Secondary outcomes include the prevalence of SCI in NTG patients and other risk factors associated with progression. There were no significant differences in the baseline intraocular pressures (IOPs), fluctuation amplitude of pretreatment IOP, baseline visual acuity, vertical cup-to-disc ratio, vertical disc diameter, presenting field indices, and central corneal thickness (CCT) between the 2 groups. Patients with SCI were significantly older compared with SCI- patients (72.4+/-10.7 vs. 63.2+/-14.2 years; P<0.001). Univariate analyses revealed age, fluctuation amplitude of pretreatment IOP, thinner CCT, presence of disc hemorrhage, systemic hypertension, arrhythmia, and SCI were significant for field progression. Silent cerebral infarct was present in 29.6% of field-progressed subjects versus 15.3% of field-stable subjects (P = 0.004). Kaplan-Meier survival analysis revealed that 65.6% of SCI+ versus 45.9% of SCI- patients had progressed (P = 0.003). Cox proportional hazards regression analysis showed disc hemorrhage (hazard ratio [HR], 2.28; 95% confidence interval [CI], 1.54-3.37; P<0.001), SCI (HR, 1.61; 95% CI, 1.09-2.36; P = 0.016), systemic hypertension (HR, 1.48; 95% CI, 1.04-2.10; P = 0.029), and CCT (per 30 mum of thinning; HR, 1.35; 95% CI, 1.16-1.75; P<0.001) were associated with field progression. Other variables significant in the univariate analysis were not significant in the regression model. The most common location of SCI was at the basal ganglia. Presence of SCI may be an independent risk factor for visual field progression in patients with NTG.

· Background: A study was carried out to measure the displacement of retinal ganglion cells subserving the cones within the human fovea. · Methods: Four human retinas were examined along the nasal or vertical hemi-meridians. Total displacement was estimated by adding the displacement due to fibres of Henle and bipolar cells, measured as the lateral extension of the Henle fibres and of the obliquely running fibre bundles within the inner nuclear layer, respectively. · Results: At the foveal border (0.5–0.8 mm or 1.8–2.9 deg eccentricity) the mean offset due to fibres of Henle and mean total lateral displacement was at a maximum of 0.32±0.03 mm and 0.37±0.03 mm, respectively. A steep decrease of displacement was found outside the foveal border out to an eccentricity of 2.0–2.5 mm. We were able to plot displacement along the vertical meridian in relation to eccentricity with good correlation between three eyes. The data were used to establish different mathematical functions describing the relation between eccentricity and displacement. These functions were applied to previously presented data on densities of retinal ganglion cells and cones. · Conclusions: The present estimates of displacement within the human central fovea offer the possibility of analysis of quantitative relations between cones and retinal ganglion cells. Our data provide predictive guidance by establishing that vitreo-retinal procedures causing damage to retinal ganglion cells up to 1 mm from the foveal centre could have implications for loss of information generated within the fovea.

A 20-year-old woman with bilateral mild blurring of vision presented with a bull's eye maculopathy and was diagnosed with Stargardt disease, confirmed with genetic testing. The authors present several novel multimodal imaging findings including multicolor and multi-spectral imaging that enhanced visualization of perifoveal flecks, fundus autofluorescence that revealed both perifoveal and perimacular rings of hyperautofluorescence, adaptive optics imaging that revealed unprecedented visualization of cones at the fovea due to decreased cone density, and spectral-domain optical coherence tomography that identified thickening and increased hyperreflectivity of the external limiting membrane as a possible transient biomarker of early Stargardt disease. [Ophthalmic Surg Lasers Imaging Retina. 2015;46:257-261.].

Eccentric viewing is a common strategy used by people with central vision loss (CVL) to direct the eye such that the image falls onto functioning peripheral retina, known as the preferred retinal locus (PRL). It has been long acknowledged that we do not know whether the PRL used in a fixation test is also used when performing tasks. We present an innovative method to determine whether the same PRL observed during a fixation task was used to watch videos and whether poor resolution affects gaze location. The gaze of a group of 60 normal vision (NV) observers was used to define a democratic center of interest (COI) of video clips from movies and television. For each CVL participant (N = 20), we computed the gaze offsets from the COI across the video clips. The distribution of gaze offsets of the NV participants was used to define the limits of NV behavior. If the gaze offset was within this 95% degree confidence interval, we presumed that the same PRL was used for fixation and video w...

To determine the ability of blue-on-yellow multifocal visual evoked potentials (BonY mfVEP) to identify functional loss in preperimetric glaucoma. Prospective case series. Thirty patients with glaucomatous optic discs and normal standard visual fields. All patients underwent BonY mfVEP, dilated optic disc stereophotography, and optical coherence tomography (Fast RNFL protocol). Optic disc photographs were assessed by 2 independent examiners in a masked fashion. The mfVEP amplitude asymmetry and latency values were analyzed and compared topographically with findings of disc assessment. Average retinal nerve fiber layer (RNFL) thickness, RNFL asymmetry, and sectors with RNFL thinning were compared between patients with and without mfVEP defects. Fourteen (46.7%) patients demonstrated significant abnormality on amplitude asymmetry deviation plots of BonY mfVEP. In all 14 cases, the defect was monocular and corresponded to the eye with the worse disc. In 13 of 14 patients, the defect also corresponded to the location of the worst affected rim. Average RNFL thickness of eyes with mfVEP defects was 81.2+/-9.9 microm, significantly lower than that of patients without defects (90+/-10.5 microm; P = 0.035). Mean asymmetry of RNFL (better minus worse eye) also was significantly higher for patients with mfVEP defects compared with those without such defects (9.0+/-6.4 microm vs. 3.0+/-7 microm; P = 0.03). Average latency of both eyes of glaucomatous patients was delayed compared with that of controls, with no difference in latency between worse and better eyes of glaucoma patients. There was no association of latency delay with either the location of disc changes or mfVEP amplitude defects. Amplitude asymmetry of the BonY mfVEP seems to be a promising tool to identify functional loss in preperimetric glaucoma. Proprietary or commercial disclosure may be found after the references.

Understanding the differences in vascular microcirculation of the peripapillary retinal nerve fiber layer (RNFL) between the hemispheres in eyes with glaucoma with single-hemifield visual field (VF) defects may provide insight into the pathophysiology of glaucoma. To investigate the changes in the microcirculation of the peripapillary RNFL of eyes with glaucoma by using optical microangiography. Eyes with glaucoma and single-hemifield VF defect and normal eyes underwent scanning using an optical microangiography system covering a 6.7 × 6.7-mm2 area centered at the optic nerve head. The RNFL microcirculation was measured within an annulus region centered at the optic nerve head divided into superior and inferior hemispheres. Blood flux index (the mean flow signal intensity in the vessels) and vessel area density (the percentage of the detected vessels in the annulus) were measured. Differences in microcirculation between the hemispheres in eyes with glaucoma and normal eyes and corre...