A 37-year-old man experienced cortical blindness following a bilateral stroke in the territory of the posterior cerebral arteries. Four years later, the measurement of visual field defects (Goldmann perimeter) showed persistence of bilateral blindness with a 2-degree preservation of macular vision and a perifoveal sparing between 10 to 30 degrees of eccentricity in the left inferior quadrant. Despite this visual impairment, the subject was able to perform visually-guided locomotion. Moreover he consciously perceived visual motion in the blind parts of his visual field. CT and MRI showed a lesion involving most of the striated cortex. The visual cortex located in the internal occipito-parital regions was relatively spared. The contribution of this structure to extra-striated vision of motion is discussed.
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Am J Ophthalmol Case Rep
March 2025
State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China.
Purpose: This study highlights the feasibility of femtosecond laser-assisted large-diameter lamellar corneal-limbal keratoplasty and its efficacy in the treatment of ocular surface failure caused by bilateral ocular chemical injury.
Observations: The series included 3 patients with ocular surface failure caused by bilateral ocular chemical burns. After dissection of the host cornea, a femtosecond laser-assisted large-diameter lamellar corneoscleral button, with varying thickness of 250-400 μm, was sutured to the recipient bed.
ACS Appl Mater Interfaces
January 2025
Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, Beijing 100730, China.
Multiple ocular surface disorders are associated with the mechanical properties of the interface between the eyelid and cornea. Determining eyelid pressure is vital for diagnosing and preventing these disorders. However, current measurements rely on flat piezoresistive pressure sensor arrays that lack eye-motion sensing capabilities, resulting in discomfort and measurement inaccuracies.
View Article and Find Full Text PDFAdv Healthc Mater
January 2025
Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Here a bioengineered platform is introduced to investigate adverse effects of environmental materials on the human cornea. Using primary cells, this system is capable of reproducing the differentiated corneal epithelium and its underlying stroma in the human eye, which can then be treated with externally applied solid, liquid, or gaseous substances in a controlled manner and under physiologically relevant conditions. The proof-of-principle of how this system can be used to simulate human ocular exposure to different classes of environmental toxicants for direct visualization and quantitative analysis of their potential to induce acute corneal injury and inflammation is demonstrated.
View Article and Find Full Text PDFClin Auton Res
January 2025
Neuro-E-Motion Research Team, Department of Psychology, Faculty of Health Sciences, University of Deusto, 48007, Bilbao, Spain.
Purpose: The aim of the study is to analyze and compare the cognitive profile between 59 patients with long-COVID [LC; 30 of them with and 29 without a positive coronavirus disease 2019 (COVID-19) confirmatory test] and 31 patients with postural orthostatic tachycardia syndrome (POTS) and a matched group of 39 healthy control participants.
Methods: Participants were examined on a battery of neuropsychological tests, including verbal memory, visuospatial abilities, attention, processing speed, verbal fluency, working memory, and visual memory. Anxious-depressive symptomatology was also analyzed and then controlled for possible influence on cognitive performance.
Brain Cogn
January 2025
Department of Nursing, Air Force Medical University, Xi'an, China. Electronic address:
The present study focused on the influence of training methods and task difficulty on event-related potentials (ERPs) at early and later visual perceptual learning (VPL) on a coherent motion identification task. Sixty participants were randomly divided into four groups for training with an adaptive stimulus (staircase group) and three constant stimuli (moderate, easy and difficult intensity groups). Visual performance improved in the staircase and moderate training groups but not in the easy or difficult training groups.
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