Color vision defects
Clinical background Key symptoms and signs “Normal” color vision refers to the form of trichromatic color vision shared by most humans. It is mediated by three types of retinal cone…
Clinical background Key symptoms and signs “Normal” color vision refers to the form of trichromatic color vision shared by most humans. It is mediated by three types of retinal cone…
Overview Diabetic macular edema (DME) can cause structural retinal changes severe enough to make it the most common cause of visual loss in patients with diabetes. DME is defined by…
Clinical background Clinical manifestations of dry age-related macular degeneration (AMD) include drusen, retinal pigment epithelium (RPE) hyperplasia, RPE depigmentation, and geographic atrophy (GA) ( Box 68.1 ). The prevalence of…
Clinical background Introduction Diabetes mellitus is a metabolic disorder caused by defects in insulin secretion (type 1), insulin action (type 2), or both. It is characterized by chronic hyperglycemia which…
Overview Diabetic retinopathy remains a major cause of morbidity in diabetic patients. To date, the retinopathy has been defined based on lesions that are clinically demonstrable, and all of those…
Clinical background Duane retraction syndrome is a congenital cranial dysinnervation disorder characterized by uni- or bilateral abduction deficit, narrowing of the palpebral fissure on adduction, and globe retraction with occasional…
Evolution has bestowed humans and other frontal-eyed foveate animals with considerable overlap of the visual fields from the right and left eye. This allows for binocular vision and stereopsis. The…
Overview Sebaceous cell carcinomas account for 1–5% of all eyelid malignancies and primarily affect older adults with a slight female gender bias. Despite representing a small fraction of all eyelid…