Charles Bonnet syndrome as first manifestation of occipital infarction

Purpose To describe a case of Charles Bonnet syndrome as the first manifestation of occipital infarction in a patient with preserved visual acuity. Observations We report a 78-year-old man followed in our department with a two-month-long history of visual hallucinations based on the vision of flowers and fruits intermittently, being perceived as unreal images. Best-corrected visual acuity was stable in the follow-up time being 20/20 in the right eye and 20/25 in the left eye. Extraocular muscle function testing, pupillary reflexes, biomicroscopy, fundus and optical coherence tomography examinations did not reveal any interesting findings. In order to rule out occipital pathology, orbital-cerebral magnetic resonance imaging was performed, showing an image compatible with the chronic ischemic right occipital lesion. The patient was diagnosed with Charles Bonnet syndrome secondary to occipital infarction and neurology decided that no treatment was required. 24-2 and 10-2 visual field tests showed no remarkable alterations and Full-field 120 point screening test showed nonspecific peripheral defects. Hallucinations improved over the months, being described as not annoying and increasingly infrequent. Conclusions and Importance Charles Bonnet syndrome is a condition characterized by the presence of recurrent and complex visual hallucinations in patients with visual pathway pathologic defects. Visual acuity or visual field loss is not a requirement for diagnosis. Charles Bonnet syndrome should be suspected in all patients with non-disturbing visual hallucinations, even though they present good visual acuteness. It will be essential to perform complementary explorations to identify the underlying pathology that allows the starting of a correct treatment option.

Linking Multi-Modal MRI to Clinical Measures of Visual Field Loss After Stroke

Loss of vision across large parts of the visual field is a common and devastating complication of cerebral strokes. In the clinic, this loss is quantified by measuring the sensitivity threshold across the field of vision using static perimetry. These methods rely on the ability of the patient to report the presence of lights in particular locations. While perimetry provides important information about the intactness of the visual field, the approach has some shortcomings. For example, it cannot distinguish where in the visual pathway the key processing deficit is located. In contrast, brain imaging can provide important information about anatomy, connectivity, and function of the visual pathway following stroke. In particular, functional magnetic resonance imaging (fMRI) and analysis of population receptive fields (pRF) can reveal mismatches between clinical perimetry and maps of cortical areas that still respond to visual stimuli after stroke. Here, we demonstrate how information from different brain imaging modalities—visual field maps derived from fMRI, lesion definitions from anatomical scans, and white matter tracts from diffusion weighted MRI data—provides a more complete picture of vision loss. For any given location in the visual field, the combination of anatomical and functional information can help identify whether vision loss is due to absence of gray matter tissue or likely due to white matter disconnection from other cortical areas. We present a combined imaging acquisition and visual stimulus protocol, together with a description of the analysis methodology, and apply it to datasets from four stroke survivors with homonymous field loss (two with hemianopia, two with quadrantanopia). For researchers trying to understand recovery of vision after stroke and clinicians seeking to stratify patients into different treatment pathways, this approach combines multiple, convergent sources of data to characterize the extent of the stroke damage. We show that such an approach gives a more comprehensive measure of residual visual capacity—in two particular respects: which locations in the visual field should be targeted and what kind of visual attributes are most suited for rehabilitation.

Autoimmune retinopathy with associated anti-retinal antibodies as a potential immune-related adverse event associated with immunotherapy in patients with advanced cutaneous melanoma: case series and systematic review

ObjectiveTo demonstrate the spectrum of autoimmune retinopathy (AIR) associated with immunotherapy for advanced cutaneous melanoma.Methods and analysisRetrospective chart review on patients with advanced cutaneous melanoma who developed AIR after initiating immunotherapy. Complete ophthalmic examination and relevant ancillary testing were performed on each patient. The presence of AIR-associated anti-retinal antibodies was confirmed by western blot and/or immunohistochemical staining. Ophthalmic and systemic outcomes after treatment for AIR were followed over time. A systematic review of AIR associated with immunotherapy for cutaneous or non-ocular mucosal melanoma was carried out in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.ResultsCase 1 developed photopsia and nyctalopia with electroretinographic findings characteristic for melanoma-associated retinopathy 1 week after initiating ipilimumab/nivolumab immunotherapy. Case 2 experienced new severe bilateral visual field loss associated with anti-retinal and anti-optic nerve antibodies while on maintenance nivolumab immunotherapy. Case 3 developed decreased visual acuity due to acute exudative polymorphous vitelliform maculopathy within 2 weeks of initiating ipilimumab/nivolumab immunotherapy. All patients had concurrent extraocular immune-related adverse events in addition to the presence of anti-retinal antibodies on serological testing. 14 published cases of AIR associated with immunotherapy for cutaneous or non-ocular mucosal melanoma were identified and reviewed.ConclusionsImmune checkpoint inhibition can trigger the development of AIR with varied clinical manifestations in patients with advanced cutaneous melanoma. This study highlights the need for close monitoring in cutaneous melanoma patients receiving immunotherapy who develop new visual symptoms with or without funduscopic changes, as well as the potential role for screening of patients prior to initiating immunotherapy.

Factors Affecting Uptake of Orientation and Mobility Rehabilitation Training among Blind Older People in Nigeria

he study investigated the factors affecting the low uptake of Orientation and Mobility Rehabilitation Training (O&M RT) among 350 legally blind (VA ≤ LogMAR -1.00 and/or visual field loss to less than 10°) older adults aged ≥ 60 years who had never gone for O&M RT.

Comparative quantification of focal and diffuse visual field loss by the SPARK Precision threshold algorithm and SITA

Purpose The aims of this paper were to examine focal and diffuse visual field loss in terms of threshold agreement between the widely used SITA Standard Humphrey Field Analyser (HFA) threshold algorithm with the SPARK Precision algorithm (Oculus Twinfield 2). Methods A total of 39 treated glaucoma patients (34 primary open angle and 5 primary angle closure glaucoma) and 31 cataract patients without glaucoma were tested in succession with the Oculus Twinfield 2 (Oculus Optikgeräte GmbH, Wetzlar, Germany) using the SPARK Precision algorithm and with the HFA 3 (Carl Zeiss Meditec, Dublin, CA) using the 30–2 SITA Standard algorithm. Results SPARK Precision required around half the testing time of SITA Standard. There was a good correlation between the MS of the two threshold algorithms but MD and PSD were significantly less severe with SPARK Precision in both glaucoma (focal field loss) and cataract (diffuse field loss) groups (p < 0.001). There was poor agreement for all global indices (MS, MD and PSD) between the two algorithms and there was a significant proportional bias of MD in the glaucoma group and PSD in both glaucoma and cataract groups. The pointwise sensitivity analysis yielded higher threshold estimates in SPARK Precision than in SITA Standard in the nasal field. Classification of glaucoma severity using AGIS was significantly lower with SPARK Precision compared to SITA Standard (p < 0.001). Conclusion SITA renders deeper defects than SPARK. Compared to the SITA Standard threshold algorithm, SPARK Precision cannot quantify early glaucomatous field loss. This may be due to the mathematical linear interpolation of threshold sensitivity or deeper scotomas due to the plateau effect caused by the reduced dynamic range of the Twinfield 2 perimeter. Although not of clinical significance in early glaucoma, the plateau effect may hinder the long-term follow-up of patients during disease progression.

Differing Associations between Optic Nerve Head Strains and Visual Field Loss in Normal- and High-Tension Glaucoma Subjects

Purpose: To study the associations between optic nerve head (ONH) strains under intraocular pressure (IOP) elevation with retinal sensitivity in glaucoma subjects. Design: Clinic based cross-sectional study. Participants: 229 subjects with primary open angle glaucoma (subdivided into 115 high tension glaucoma (HTG) subjects and 114 normal tension glaucoma (NTG) subjects). Methods: For one eye of each subject, we imaged the ONH using spectral-domain optical coherence tomography (OCT) under the following conditions: (1) primary gaze and (2) primary gaze with acute IOP elevation (to approximately 33 mmHg) achieved through ophthalmodynamometry. A 3-dimensional (3D) strain-mapping algorithm was applied to quantify IOP-induced ONH tissue strain (i.e. deformation) in each ONH. Strains in the pre-lamina tissue (PLT) and the retina, the choroid, the sclera and the lamina cribrosa (LC) were associated (using linear regression) with measures of retinal sensitivity from the 24-2 Humphrey visual field test (Carl Zeiss Meditec, Dublin, CA, USA). This was done globally, then locally according to the regionalization scheme of Garway-Heath et al. Main Outcome Measures: Associations between ONH strains and values of retinal sensitivity from visual field testing. Results: For HTG subjects, we found that (1) there were significant negative linear associations between ONH strains and retinal sensitivity (p<0.001) (on average, a 1% increase in ONH strains corresponded to a decrease in retinal sensitivity of 1.1 dB), (2) high strain regions co-localized with anatomically-mapped regions of high visual field loss, (3) the strongest negative associations were observed in the superior region and in the PLT. In contrast, for NTG subjects, no significant associations between strains and retinal sensitivity were observed except in the supero-temporal region of the LC. Conclusion: We found significant negative associations between IOP-induced ONH strains and retinal sensitivity in a relatively large glaucoma cohort. Specifically, HTG subjects who experienced higher ONH strains were more likely to exhibit lower retinal sensitivities. Interestingly, this trend was in general less pronounced in NTG subjects, which could suggest a distinct pathophysiology between the two glaucoma subtypes.