Does Perisaccadic Compression Require Foveal Vision?

Perception ◽  
10.1068/p7666 ◽  
2014 ◽  
Vol 43 (11) ◽  
pp. 1214-1224
Author(s):  
Maria Matziridi ◽  
Mijke O Hartendorp ◽  
Eli Brenner ◽  
Jeroen B J Smeets
Keyword(s):  
Macular Degeneration ◽  
Systematic Errors ◽  
High Density ◽  
Retinal Locus ◽  
Central Vision ◽  
Foveal Vision ◽  
Central Retina

People make systematic errors when localizing a stimulus that is presented briefly near the time of a saccade. These errors have been interpreted as compression towards the position that is fixated after the saccade. Normally, fixating a position means that its image falls on the fovea. Macular degeneration (MD) damages the central retina, obliterating foveal vision. Many people with MD adopt a new retinal locus for fixation, called the preferred retinal locus (PRL). If the compression of space during the saccade is a special characteristic of the fovea, possibly due to the high density of cones that is found in the fovea, one might expect people lacking central vision to show no compression of space around the time of a saccade. If the compression of space during the saccade is related to the position that is fixated after the saccade, one would expect compression towards the PRL, despite the lack of a high density of cones in this area. We found that a person with MD showed a clear compression towards her PRL. We conclude that perisaccadic compression is related to the position that is fixated after the saccade rather than to the high density of receptors in the fovea.

scholarly journals Visual search without central vision – no single pseudofovea location is best

2014 ◽  
Vol 7 (2) ◽  
Author(s):  
Angelika Lingnau ◽  
Thorsten Albrecht ◽  
Jens Schwarzbach ◽  
Dirk Vorberg
Keyword(s):  
Visual Search ◽  
Macular Degeneration ◽  
Spatial Resolution ◽  
Central Vision ◽  
Foveal Vision ◽  
Scan Path ◽  
Path Direction ◽  
Retinal Region ◽  
Field Location

We typically fixate targets such that they are projected onto the fovea for best spatial resolution. Macular degeneration patients often develop fixation strategies such that targets are projected to an intact eccentric part of the retina, called pseudofovea. A longstanding debate concerns which pseudofovea-location is optimal for non-foveal vision. We examined how pseudofovea position and eccentricity affect performance in visual search, when vision is restricted to an off-foveal retinal region by a gaze-contingent display that dynamically blurs the stimulus except within a small viewing window (forced field location). Trained normally sighted participants were more accurate when forced field location was congruent with the required scan path direction; this contradicts the view that a single pseudofovea location is generally best. Rather, performance depends on the congruence between pseudofovea location and scan path direction.

scholarly journals Photovoltaic Restoration of Central Vision in Atrophic Age-Related Macular Degeneration

Ophthalmology ◽  
2020 ◽  
Vol 127 (8) ◽  
pp. 1097-1104 ◽  
Author(s):  
Daniel Palanker ◽  
Yannick Le Mer ◽  
Saddek Mohand-Said ◽  
Mahiul Muqit ◽  
Jose A. Sahel
Keyword(s):  
Macular Degeneration ◽  
Age Related Macular Degeneration ◽  
Central Vision ◽  
Age Related

Implantation of the First IMT Macular Lens in Age-Related Macular Degeneration (Literature Review)

2019 ◽  
Vol 4 (4) ◽  
pp. 56-60
Author(s):  
M. M. Bikbov ◽  
O. I. Orenburkina ◽  
A. E. Babushkin
Keyword(s):  
Visual Field ◽  
Macular Degeneration ◽  
Peripheral Vision ◽  
Age Related Macular Degeneration ◽  
Central Vision ◽  
Central Visual Field ◽  
Visual Rehabilitation ◽  
Age Related ◽  
Terminal Form ◽  
Special Programs

This review presents the characteristics and results of clinical studies of patients with age-related macular degeneration implanted with the developed for this purpose first macular IOL – intraocular macular telescope (IMT). This lens was designed specifically for patients with the most severe or terminal form of age-related macular degeneration and is designed for monocular implantation to provide central vision while maintaining peripheral vision of the paired eye, which is important for maintaining the balance and orientation of patients. This device allows patients to see both in dynamic and static situations in the near, intermediate and far ranges. The disadvantages of this lens are a decrease in the visual field and depth of focus (which excludes its bilateral implantation), the need for a large (10–12 mm) incision for implantation, which can cause an increase in corneal astigmatism and the risk of complications, in particular, the pupillary block with an increase in intraocular pressure. There are also difficulties in the study of the fundus after its implantation to assess the small changes in the macula or to identify possible postoperative complications after cataract surgery (macular oedema, etc.). Also after the implantation of this lens, there is need for special programs of visual rehabilitation. The patient’s commitment to the rehabilitation measures for the adaptation of the central visual field of the operated eye with the peripheral vision of the second eye is crucial for success of the IMT macular telescope implantation procedure.

Concept of a functional retinal locus in age-related macular degeneration

2010 ◽  
Vol 45 (1) ◽  
pp. 62-66 ◽  
Author(s):  
Noboru Shima ◽  
Samuel N. Markowitz ◽  
Sophia V. Reyes
Keyword(s):  
Macular Degeneration ◽  
Age Related Macular Degeneration ◽  
Retinal Locus ◽  
Age Related

scholarly journals Nutritional Therapy in Dry-form (Non-Neovascular) Age-Related Macular Degeneration

2017 ◽  
pp. 135-144
Keyword(s):  
Macular Degeneration ◽  
Treatment Options ◽  
Nutritional Therapy ◽  
Age Related Macular Degeneration ◽  
Central Vision ◽  
Multiple Factors ◽  
Age Related ◽  
Health Factors ◽  
Degenerative Disorder ◽  
Systemic Health

Age-related macular degeneration (AMD) is a progressive degenerative disorder of the macula in which central vision becomes impaired and leading cause of blindness in adults older than 55 years. Multiple factors have been proposed for the pathogenesis of AMD including genetic susceptibility interacting with environmental and systemic health factors. Nowadays, treatment options for dry-form AMD are limited. Among these treatments, nutritional therapy is at the forefront. This review mentions about the nutritional therapy in dry-type AMD.

scholarly journals AGE RELATED MACULAR DEGENERATION (ARMD) CLINICAL PROFILE AND MANAGEMENT

2021 ◽  
Vol 5 (02) ◽  
Author(s):  
Sanjay Thokare
Keyword(s):  
Macular Degeneration ◽  
Visual Loss ◽  
Age Related Macular Degeneration ◽  
Macular Area ◽  
Central Vision ◽  
Loss Of Vision ◽  
Age Related ◽  
Gradual Loss ◽  
Wet Amd ◽  
Additional Option

Age Related Macular Degeneration (ARMD) next to cataract is the leading cause  visual loss in elderly. My study is to focus on cleanical profile of Age Related Macular Degeneration with effective Ayurveda management to increasing in average longitivity of an individual with advance in science and technology along with traditional  management.In research scenario it has been demonstrated that choroidal neovascular lesion of Age Related Macular Degeneration. Account for most of severe loss of vision attributed to this condition. My study tries to give additional option and contribution of Ayurveda to patient affected with Age Related Macular Degeneration. Macula is area which correspond to centre of vision. There are two types Dry and Wet ARMD based on appearance of  exudates and tiny haemorrhage in the macular area . in wet AMD treatment of Raktpitta should be followed. Though  description of macular degeneration is not described is classics . Gradual loss of vision in Timira we can assume this regenerative pathology as Prakopita Vatalakshana in Drushti Mandala .  Inn proper Tarpak Kapha result in weakening of function and death of life sensing cells of macula . In dry Age Related Macular Degeneration this cells breakdown slowly and result in loss of central vision . These can be stated Kaphavata Drushtijanya Timira . In case of wet AMD abnormal blood vessels start to grow under macula and eventually bleed . This explains Raktpitta Drushti . Management of Age Related Macular Degeneration should be done on the principle of Vatavyadhi with Rasayan Chikitsa . 

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