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CNS Pathology. RT 91 Fall 2011 Final. CRANIAL FRACTURES. Cranial Fractures. Cerebral fractures usually occurs to fractures of the calvaria of the skull 3 types of cranial fractures ____________- straight and sharply defined Is 80% of all cranial fractures
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CNS Pathology RT 91 Fall 2011 Final
Cranial Fractures • Cerebral fractures usually occurs to fractures of the calvaria of the skull • 3 types of cranial fractures • ____________- straight and sharply defined • Is 80% of all cranial fractures • ____________- curvilinear density • ____________- Air fluid levels are indicative • Hard to diagnosis radiographically
Cranial Fractures • Location of FX is more important that the extent of the FX • If FX crosses artery a bleed can occur causing a hematoma • Fx that enters mastoid air cells or sinus can cause an infection that can result in • Meningitis • Encephalitis
_______ Fractures • Non branching lines that are intensely radiolucent • Vascular markings are occasionally mistaken for fractures • Fracture appears more translucent and transverses the full thickness of skull • Sutures
__________ Fracture • The fractured edges ________ • Usually caused by a high velocity impact with a small object • Can cause bleeding into ______________ space • Best demonstrated with CR __________to the FX
_______________Fracture • Very difficult to demonstrate with x-ray • __________________ in sphenoid sinuses • Clouding of ________________________________ • Often X-table lateral is done to demonstrate this • CT & MRI are most often used for this type
Meninges • Has protective membranes that enclose the brain and spinal cord • Dura Mater- outer most layer • Tough and fibrous • Arachnoid = middle layer • Has appearance of cobwebs • Pia mater = innermost layer • highly vascular and closely adhered to cortex and spinal cord • Subarachnoid space = wide space between arachnoid and pia mater • Filled with CSF • Bathes brain & spinal cord with nutrients • Cushions against shocks and blows
Ventricular System • Four irregular interconnected- fluid-containing cavities • Cerebrospinal fluid (CSF) = tissue fluid of the brain and spinal cord that surrounds and cushions CNS • Ventricles communicate with each other through connecting channels • Lateral ventricles = one on each side of MSP in corresponding hemispheres of cerebrum
Ventricular System • Interventricular foramen = connects lateral ventricles to third ventricle • Also called foramen of Monroe • Third ventricle is slitlike cavity somewhat quadrilateral in shape • Situated in MSP, just inferior to lateral ventricles • Cerebral aqueduct = connects third and fourth ventricle; also called aqueduct of Sylvius
Cerebral ______________ • Is an injury to the brain tissue caused by a ____________ of the brain within the calvaria after ______________________ • Occurs when brain contacts rough skull surfaces such as _______&___________ • PT usually loses consciousness and cannot remember traumatic event • Persitent LOC over 24 hrs is a coma and can be fatal
Clinical symptoms: Drowsiness Confusion Agitiation Hemiparesis Unequal pupil size Treatment: PT is hospitalized Prevent shock If there is swelling medication is given to decrease cranial pressure Control edema Draniage of hematoma Surgery is usually not necessary Cerebral Contusion
Hematomas • Brain trauma often resulting in a hemorrhaging from a ruptured ______________________ • __________bleeding occurs more slowly than arterial bleeding • _________bleed accumulates fast & causes neurologic symptoms & coma • Both can cause edema in the brain and cause an increase in intracranial pressure • Skull does not allow for expansion and pressure forces brain toward open space (foramen magnum) • Can result in major consequences & death if not treated quickly
______________Hematomas • Highest mortality relate of the hematomas • Even when treated quickly mortality rate is 30% • Results from a torn _________ and its branches • Most often occurs from a FX of the _______ bone • 80% of cases conventional radiograph shows fracture • Usually _______________ with blood pooling between bones of the skull & _______________
____________Hematoma Usually a shift of midline Toward ________ side CT shows increased density Emergency surgical decompression is required to relieve cranial pressure
_______________ Hematomas • Between the __________&___________ • Caused by blunt trauma to frontal or occipital lobes and can tear ____________________ • Pushes brain away from skull across midline (including ventricles)
_____________Hematoma Occurs more slowly Because it is a ________ Hemorrhage. On CT appears as a curvilinear area of I increased density on portions or all of the cerebral hemispheres
______________Hematomas • Subacute stage (up to several days) • Appears on CT as a decreased density or isodense fluid collection • In chronic state (2-3 weeks) • The surface of the hematoma becomes concave • Delayed coma cn occur
Symptoms of Hematomas • Headaches • Agitation • Drowsiness • Gradual radiograph deficits
Treatment of Hematomas • In small hematomas without inclination to rebleed • the hemorrhage is reabsorbed naturally • no treatment is necessary • Severe cases • Require surgical ligation • Evacuation of hematoma to prevent herniation • Less invasive treatment may include • Drug therapy • Intraventricular catheter to remove CSF, which may cause herniation
_______________ • Can be _______________ or ________________ • Refers to an excessive amount of fluid in the ventricles • Two types • _______________________________ • Interferes or blocks normal CSF circulation from the ventricles to the subarachnoid space • _________________________________ • Poor absorption of the CSF by the arachnoid Villi • Least common cause is from overproduction of CSF
Non-communicating Can be congenital Can be from tumor growth Trauma (hemorrhage) Inflammation Communicating Can come with increased cranial pressure Raised intrathoracic pressure impairing venous flow Inflammation from meningitis Subarachnoid hemorrhage _________________________
Radiographic Appearance • Generalized enlargement of the ventricular system • PA radiograph can reveal separation of the ___________ • CT clearly demonstrates ventricular dilatation • MRI is more specific in demonstrating the underlying cause of obstruction or in excluding obstruction • Ultrasound is useful in utero and in infants • Sound waves transverse open fontanels
Hydrocephalus Clinical Symptoms • The cranial size is enlarged • Scalp veins distended • Skin of scalp thin, fragile and shiny • Neck muscles underdeveloped • Severe cases • Orbital roofs are depressed • Eyes displaced downwards • In adults • ALOC • Ataxia • Incontinence • Decreased intellectual • capabilities
Treatment of Hydrocephalus • Placement of a ________ • Internal jugular, heart or peritoneum • Contains one way valve to prevent backflow of blood into ventricles • Radiographs taken to verify _______________ • CT or MRI done to evaluate success of treatment
Hydrocephalus in Infants • Affects 1 of every 1000 newborns • Long maturation of CNS • Can be caused by maternal & fetal infections, fetal hypoxia, irradiation, chemical agents and mechanical forces
________________________ • Is an atherosclerotic disease affecting blood supply to the brain • ______________leading cause of death in U.S. • 2 types of stroke: • ___________________________________ • Both CT and MRI distinguish between the two types • MRI is especially sensitive to infarction within hours of onset • CT, at times appears negative for a day or so • Carotid duplex and MRA are also useful in the diagnosis of a stroke
________________ Stroke • Blood clot blocks a blood vessel in the brain • Is the majority of strokes • Two types: • ____________________ of cerebral artery • Blood clot that blocks a blood vessel • ____________________ of the brain • Is a mass of undissolved matter (solid, liquid or gas) present in a blood vessel brought there by blood current • Diagnosed with CT and MRI • Angiography can be used if other modalites are questionable
Symptoms of ________ __________Stroke • Sypmtoms come on over horus to days • Confusion • Hemiplegia • Aphasia • May be preceded by a temporary episode of nerurologic dysfunction called transient ischemic attack (TIA) • Includes hemiparesis, monocular blindness- clears up in about 2 hours
Ischemic Stroke: from ______ • ___________ onset of symptoms without warning • Mortality rate is_______________ • Prognosis depends on location, extent, age, and general health • Complete recovery is rare • Deficits remaining after 6 months are likely to be permanent • Treatment • Bed rest • Clot blockers within 3 hours (recombinant tissue plasminogen activator (rtPA)
________________ Stroke • Occurs from a __________ in the diseased blood vessel • Typically weakened from atheroscleosis from hypertension • Sudden and often lethal because it comes on so suddenly • Accounts for _____________of all CVA’s • Two types: • _______________-&___________________
Hemorrahgic Stroke • Most occur in the ________ and bleed into lateral ventricle • Most often preceded by an intense headache and vomiting • LOC follows in minutes and leads to contralateralhemiplegia or death • Prognosis is poor • ___________ die day after stroke • ___________die within a few weeks, usually from another vessel rupture
Treatment ofHemorrahgic Strokes • Surgery • Preceded by a surgical angiogram • If surgical intervention is postponed so will the angiogram
