neuro clinical correlations lec 23-27
About this set
Created by:
feiyingluu on March 3, 2011
Subjects:
Log in to favorite or report as inappropriate.
Order by
20 terms
Terms | Definitions |
|---|---|
 shingles (herpes zoster) | following an attack of chickenpox the herpes virus may become latent in dorsal root ganglion cells (or trigeminal ganglion cells), reactivation of the virus produces painful skin irritations in the dermatomal area innervated by the related ganglion |
| Brown Sequard syndrome | hemisection of the spinal cord as a result of a slow growing mass or a traumatic lesion interrupting ascending and descending fibers on one side of the cord touch, vibration and proprioception are lost on one side of the body whereas pain and temperature are lost on the other side of the body at the level of the lesion, on the side of the lesion, have loss of sensations for touch,, vibration, proprioception, pain and temperature below level of lesion on same side of lesion have sensory loss of touch, vibration, and proprioception for all dermatomes below below the level of lesion on opposite side of lesion, pain and temperature sensations are lost, starting one or two segments below lesion and including all dermatomes below |
| syringomyelia | a pathological enlargment of central canal of spinal cord, can be due to cyst in anterior white commissure as cavity expands it interrupts fibers that cross through the anterior white commisure, interrupts anterior lemniscus system-->bilateral lost in pain and temperature |
| tabes dorsalis | clinical syndrome which is the consequence of a syphilitic infection, destruction of dorsal root ganglion cells with large diameter myelinated axons causes severe deficit in touch and proprioception nociception and temperature sense remain almost unaffected |
| phantom limb sensations | following the amputation of a limb the patient often feels sensations which seem to orginate from the missing limb, usually sensation of pain (neuropathic pain--deafferentation pain) likely explanation is reorganization of cortical maps, may be rearrangement or cortical input to area that formerly represented amputated limb ex for amputated hand, touch pathways originating in face are likely to form new circuits within the primary somatosensory cortex (S1) that connect them with cortical neurons that would have otherwise become "jobless" (lacking innervation from the missing limb)-->phantom limb sensation evoked by touching face |
| headache | caused by stimulation of pain-sensitive structures like the wall of blood vessels, the dura mater, and the periost no nociceptors in the brain |
| aspirin | effect of aspirin and other non-steroidal anti-inflammatory analgesics in controlling pain is due to its ability to inhibit the enzyme cyclo-oxygenase responsible for the synthesis of prostaglandins--agents which sensitize sensory afferent fibers |
| acupunture | according to NIH and the Mayo Clinic, acupuncture may offer symptomatic relief for a variety of diseases and conditions including low back pain, headaches, fibromyalgia, migraines and osteoarthritis research shows acupuncture can help manage postoperative dental pain and alleviate chemotherapy-induced nausea and vomiting appears to offer relief for chronic menstrual cramps and tennis elbow acupuncture release opioid peptides, the secretion of hypothalamic pituitary neurotramsitters and neurohormones, and alterations in immune function |
| opioids | strong pain killers, used for more serious pain conditions, activate physiological pain control circuitries by binding to opioid receptors ex. morphine, |
| surgical management of pain | used when all measures aimed at direct causes of pain have been exhausted ie to relieve otherwise intractable pain such as in terminal cancer patients ex. dorsal rhizotomy, ie transection of dorsal roots of the spinal nerves |
| myopia | the focus of parallel lights (far vision) is anterior to the photosensitive elements of the retinal photoreceptors, objects positioned closer to the eye (near visioin) can still be focused on the retina even without the contribution of the usual mechanisms for near accommodation vision is best during near vision, nearsightedness, treat with corrective lenses or corneal surgery |
| hyperopia | the focus of the parallel light rays (far vision) is beyond the retina, objects in the far distance from the eye can still be brought into focus by activating the mechanisms for near accommodation which increase the refractive power of the eye near accommodation fails for objects close to the eye and reduces the ability for near vision vision is best during far vision, farsightedness, treat with corrective lenses or corneal surgery |
| emmetropia | describes the state of vision where an object at infinity is in sharp focus with the eye lens in a neutral or relaxed state, this condition of the normal eye is achieved when the refractive power of the cornea and the axial length of the eye balance out, which focuses rays exactly on the retina resulting in perfect vision an eye in a state of emmetropia requires no correction |
| papilledema | optic disk edema, important clinical sign which can indicate increased intracranial pressure, increased pressure compromises the venous drainage of the eye leading to dilation of the retinal veins, as a consequence the optic disc is pushed forward and the disk appears white rather than pink as in normal conditions seen when inspecting the ocular fundus with an ophthalmoscope |
| detached retina | the retina separates from teh retinal pigment epithelium and the areas detached lose their function a focal lesion in a defined region causes a scotoma laser surgery can stop the process of further separation although the detached part of the retina does not regain ts function |
| age related macular degeneration (AMD) | patients have poor central vision but most can walk, dress themselves, and perform many normal daily tasks leading cause of vision loss in individual age 60+ years of in US and many European countries genetic, ocular and environmental factors, age, smoking and body mass index heavily contribute to the incidence of AMD |
| diabetic retinopathy | patients suffering from diabetes mellitus are associated with increased blood glucose levels and retina vulnerability the retinal defects are caused by blood supply dysfunction including reduction of permeability of basal membranes of capillary endothelial cells and blood vessel damage (aneurysms) during the initial phase of diabetes smaller scotomas are usually not recognized by the patient, as soon as the macula is involved the visual loss increase dramatically |
| retinitis pigmentosa | a group of serious, mostly genetically determined (autosomal dominant, autosomal recessive, X-linked) degenerative diseases in which rods preferentially degenerate one of the earliest symptoms is night blindness followed by loss of peripheral vision leading to tunnel vision a progressive disease which can lead to total blindness, accumulation of pigment can be seen through the opthalmoscope photoreceptor degeneration is often associated with reduced phagocytosis by retinal pigment epithelium (RPE) cells during process of disk shedding |
| night blindness (nyctalopia | encountered in individuals with vitamin A deficiency vitamin A is the precursor of retinal (vitamin A aldehyde) which together with the opsin protein forms the photoreceptor pigment |
| color blindness | due to a lack of a particular cone type, most common is red-green color blindness inherited by an X-linked recessive gene, appearing more frequently in male subjects individuals affected by red-green color blindness can no longer distinguish certain red colors from certain green colors two different types of red-green color blindness: protanopia--L cone (red cone) absent--affecting 1.3% of males deuteranopia--M cone (green cone) absent--affecting 1.2% of male S cone (blue cone) deficits are rare |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.