GrapesKnow

Age related macular degeneration This patient likely has age-related macular degeneration (AMD), the leading cause of blindness in industrialized countries. AMD occurs in genetically predisposed individuals as a result of advancing age and environmental factors (eg, smoking) and is classified into dry and wet subtypes. Dry AMD is characterized by gradual vision loss in one or both eyes and can cause difficulty with driving/reading. The condition likely results from chronic oxidative damage to the...

Chest anatomy and stab A penetrating, laterally directed stab wound (possibly from a left-handed assaulter) that involves the fifth intercostal space (ICS) at the left anterior midclavicular line (MCL) would most likely injure the left lung. The lungs occupy most of the volume of the thoracic cavity. The apex of each lung extends into the neck (3-4 cm above the first rib). The lung bases are in direct contact with the diaphragm, which separates the right lung from the right lobe of the liver and the left lung from the stomach, spleen, and (occasionally) left lobe of the liver...

Reperfusion injury Ischemia is characterized by the reduction of blood flow, usually as a result of mechanical obstruction within the arterial system (eg, thrombus). If the flow of blood to the ischemic tissue is restored in a timely manner, those cells that were reversibly injured will typically recover. Sometimes, however, the cells within the damaged tissue will paradoxically die at an accelerated pace through apoptosis or necrosis after resumption of blood flow. This process is termed reperfusion...

Kiesselbach plexus The nasal mucosa is highly vascular and easily irritated by trauma (eg, nose-picking), mucosal dryness, foreign body insertion, and rhinitis (eg, allergy, infection). Epistaxis is very common in children and may be classified as anterior or posterior, depending on the bleeding source. Anterior nosebleeds are by far the most common, and the vast majority occur within the vascular watershed area of the nasal septum (anteroinferior part of the nasal septal mucosa) known as Kiesselbach plexus...

This patient has Ménière disease, a disorder of the inner ear characterized by increased volume and pressure of endolymph (endolymphatic hydrops) that is thought to be due to defective resorption of endolymph. The resultant distension of the endolymphatic system causes damage to the vestibular and cochlear components of the inner ear. Ménière disease is characterized by the following triad: (Choice A) Multiple sclerosis (MS) is characterized by patchy demyelination in the central nervous system that varies over time...