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Similar to hypertensive retinopathy, evidence of nerve fiber infarcts due to ischemia (cotton-wool spots) can be seen on physical exam. Symptoms may include headache, nausea, or vomiting. Chest pain may occur due to increased workload on the heart resulting in inadequate delivery of oxygen to meet the heart muscle's metabolic needs.
This is followed by an exudative stage, in which there is disruption of the blood–retina barrier, necrosis of the smooth muscles and endothelial cells, exudation of blood and lipids, and retinal ischemia. These changes are manifested in the retina as microaneurysms, hemorrhages, hard exudates, and cotton-wool spots
[1] [2] This reduced axonal transport can then cause swelling or bulging on the surface layer of the retina, increasing the potential for nerve fiber damage. [2] The presence of cotton wool spots may resolve independently over time, typically in 4–12 weeks, or may depend on the underlying disease causing the condition.
Advanced retinopathy lesions, such as microaneurysms, blot hemorrhages and/or flame hemorrhages, ischemic changes (e.g. "cotton wool spots"), hard exudates and in severe cases swelling of the optic disc (optic disc edema), a ring of exudates around the retina called a "macular star" and visual acuity loss, typically due to macular involvement.
axial compression and rotation of cervical spine to the side of symptoms causes pain Stellwag's sign: Karl Stellwag von Carion: endocrinology: thyrotoxicosis: infrequent and/or incomplete blinking, accompanied by Dalrymple's sign: Still's murmur: Sir George Frederick Still: paediatric cardiology: subaortic stenosis, small Ventricular septal defect
Infarction occurs as a result of prolonged ischemia, which is the insufficient supply of oxygen and nutrition to an area of tissue due to a disruption in blood supply.The blood vessel supplying the affected area of tissue may be blocked due to an obstruction in the vessel (e.g., an arterial embolus, thrombus, or atherosclerotic plaque), compressed by something outside of the vessel causing it ...
≥ 0.50 diopter cycloplegic refractive changes and/or cotton-wool spot; Optic nerve sheath distention, and/or globe flattening and/or choroidal folds and/or scotoma; Optic-disc edema Grade 2 or above; Presenting symptoms of new headache, pulsatile tinnitus and/or transient visual obscurations; CSF opening pressure > 25 cm H 2 O
The re-entry phenomenon may cause rapid heart rates (ventricular tachycardia and even ventricular fibrillation), and ischemia in the electrical conduction system of the heart may cause a complete heart block (when the impulse from the sinoatrial node, the normal cardiac pacemaker, does not reach the heart chambers).