* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Disease Description Group/Types Cause/Mutations Info/Clinical
Survey
Document related concepts
Transcript
Disease Spina Bifida Occulta Description Asymptomatic bony defect or severe malformation with a flat, disorganized segment of the spinal cord with meningneal outpouching. Group/Types Neural Tube defect (Diagnosed based on imaging and screening of maternal blood for afetoprotein) Neural Tube defect Cause/Mutations Anencephaly Malformation of the anterior end of the neural tube with absence of the brain and calvarium. Megalencephaly Volume of the brain abnormally large Forebrain anomalies Microencephaly Volume of brain abnormally small Forebrain anomalies Lissencephaly (agyria) Decrease in the number of gyri to total absence leaving a smooth-surfaced brain Forebrain anomalies -Gene encoding microtubule-associated protein LIS-1 -can also be caused by enzymes responsible for glycosylation of adystroglycan Polymicrogyria Small, unusually numerous and irregular formed cerebral convolutions. This also has entraptment of apparent meningeal tissue at point of fusion that should be cortical surface. Forebrain anomalies -Induced by localized tissue injury towards the end of neuronal migration -Also genetic forms Info/Clinical symptoms - Myelomeningocele (meningomyelocele) = extension of the CNS tissue through the defect mostly in lumbar with clinical defects to motor and sensory in LE with abnormal bowel and bladder control. - Meningiocele = only meninges extrude Forebrain development is disrupted at 28 days just area cerebrovasculosa (flat remnant of brain tissue with admized ependyma, choroid plexus and meningothelial cells) Occurs in chromosome abnormalities, fetal alcohol syndrome and HIV-1 acquired inutero - LIS-1 = complexes with dynein and affects the function of the centrosome in nuclear movement. Disease Neuronal Heterotopias Description Migrational disorders where neurons are in inappropriate locations and are associated with epilepsy Heterotopia in the ventricular system Group/Types Forebrain anomalies Cause/Mutations Forebrain anomalies – Neuronal heterotopias Holoprosencephaly Incomplete separation of the cerebral hemisphere across the midline Forebrain anomalies Mutation in gene encoding filamin A (an acting binding protein assembly of the complex meshworks of filaments) Associated with trisomy 13 and other genetic syndromes Agenesis of the corpus callosum Absence of the white matter bundles that carry cortical projections from one hemisphere to the other Forebrain anomalies Dandy-Walker malformation Enlarged posterior fossa -cerebellar vermis is absent or present in rudimentary -form in its anterior portion in its place is large midline cyst lined by ependyma and is contiguous with leptomeninges Small posterior fossa, misshapen midline cerebellum with downward extension of vermis through the foramen magnum -hydrocephalus -lumbar myelo-meningocele Discontinuous multisegmental or confluent expansion of the ependyma-lined central canal Posterior fossa anomalies Periventricular Heterotopias Arnold-Chiari Malformation (type 2) Hydromyelia Posterior fossa anomalies Info/Clinical symptoms One location is in ventricular system = Periventricular heterotopias. -severe form cyclopia -less severe (arrhinenceophaly) absence of olfactory CN -severity lowest to highest: normal lobar semilobar alobar -radiological: misshapen lateral ventricle (“bat-wing” deformity) -associated with mental retardation or can occur in clinically normal individuals. -cyst in this dz represents expanded, roofless 4th ventricle in the absence of the normally vermis -Chiari malformation (type 1) = lowlying cerebellar tonsils extend down into the vertebral canal Disease Description Syngromyelia, syrinx Formation of fluid-filled cleftlike cavity in the inner portion of the cord Syringobulbia Formation of fluid-filled cleftlike cavity in the inner portion of the cord that may extend into the brainstem Ataxia Telangectasia Ataxicdyskinetic syndrome in early childhood development of telangiectasia (dilated blood vessels in outer layer of skin) in conjunctive and skin -immunodeficiency Group/Types Cause/Mutations Info/Clinical symptoms -Associated with the Chairi I and with intraspinal tumors or following traumatic injury -disease occurs in 2nd-3rd decade of life -symptoms: isolated loss of pain and temp in UE (due to crossing anterior spinal commissural fibers of the spinal cord) Autosomal recessive -ataxia-telangiectasia mutated (ATM) gene on chromosome 11 (encodes kinase needed for cell response to ds DNA breaks) -show increase sensitivity to x-ray induced chromosome abnormalities -abnormalities are predominately cerebellum with loss of Purkinje and granule cells. -Degeneration of dorsal columns, spinocerebellar tracts, anterior horn cells and peripheral neuropathy. -telangiectatic lesions are in CNS, conjunctive and skin of face, neck and arms. -disease is progressive and death early in life. -patients have recurrent sinopulmonary infections and unsteady walk later have speech problems, dysarthric, eye movement abnormalities -many develop lymphoid neoplasm, T cell leukemia Disease Sturge-Weber syndrome Description Venous angiomatous masses in the cortical leptomeninges and ipsilateral facial port wine nevi Tuberous Sclerosis in CNS Tuberous Sclerosis with NON-CNS lesions Group/Types Cause/Mutations Info/Clinical symptoms -mental retardation, seizures, hemiplegia and skull radio-opacities -(large facial vascular malformation in child with mental deficiency may indicate a extensive vascular malformations) Development of hamartomas and benign neoplasms Autosomal dominant -locus TSC1 on chromosome 9 (encodes protein hamartin) or locus TSC2 at chromosome 16 (encodes tuberin) these inhibit kinase mTOR that regulates protein synthesis and other anabolic metabolisms. -Hamartomas in CNS = cortical tubers and subependymal nodules -subependymal giant-cell astrocytomas (low grade neoplasms that develop from hamartomatous nodules) -cortical tubers are epileptogenic and sx beneficial Development of hamartomas and benign neoplasm’s Autosomal dominant -mutations same as above. -renal angiomyolipomas, retinal glial hamartomas, pulmonary lymphangioleiomyomatosis and cardiac rhabdomyomas -cysts can be found in liver, kidneys and pancreas -cutaneous lesions angiofibromas, localized leathery thickenings (shagreen patches), hypopigmented (Ash-lead patches) and subungual fibromas Disease Tay Sachs Description -Mutation leads to deficiency of hexosaminidase A (which breaksdown GM2) -Inability to catabolize GM2 ganglioside leading to accumulation of GM2 ganglioside -symptoms = motor coordination, mental obtundation muscle flaccidity, blindness and increasing dementia Group/Types GM2 Ganliosideosis Hexosaminidase a-subunit deficiency Cause/Mutations Mutation in a-subunit locus of chromosome 15 Info/Clinical symptoms -prevelent among Ashkenazic Jews -Gangliosides mostly accumulate in neurons in CNS, ANS and retina -neurons are ballooned with cytoplasmic vacuoles -stains oil red O and sudan black are positive -infants normal at birth but show symptoms at 6 months vegetative at 1-2 yrs and dead at age 2-3 y/o -cherry-red spot in macula of the eye -Clinically similar diseases: sandhoff (due to B-subunit defect) and GM2 activator deficiency Niemann-Pick disease Type A and B -Sphingomyelinase deficiency (which is required for cell membranes) so deficiency blocks degredation of the lipid resulting in accumulation of sphingomyelin in lysosome mainly in cells in mononuclear phagocyte system Sphingomyelina se deficiency Missense mutation to chromosome 11 p15.4 Type A: Almost complete deficiency of sphingomyelinase -Common in Ashkenazi Jews -Enlarged cells (90um) filled with sphingomyelin and cholesterol have a foaminess to the cytoplasm -Foam cells found in: spleen, liver, lymph nodes, bone marrow, tonsils, GI and lungs -Clinical symptoms: hepatosplenomegaly, brain gyri are shrunken and sulci, diffuse neuronal involvement, vacuolation and ballooning of neurons cell death and loss of brain substance, retinal cherryred spot -Type A: also have protuberant abdomen, progressive failure to thrive, vomiting, fever, generalized lymphadenopathy, decrease psychomotor skills. Severe infant form with Type A: neurological involvement due to visceral accumulations of sphingomyelin Apparent by 6 mo, death at 1-2 y/o -Type B: patients have organomegaly but NO CNS involvement Disease Gauchers disease Description Glucocerebroside accumulates in phagocytes or sometimes CNS. -Not only do they store more glucocerebrosides but macrophages are activated secreting cytokines: IL-1, IL-6 and TNF Chronic non-neuronopathic form glucocerebrosides limited to mononuclear phagocytes without brain involvement Group/Types There are 3 types (each listed below) Cause/Mutations Autosomal Recessive -Mutation in gene for glucocerebrosidase (which cleaves glucose residues from ceramide) Info/Clinical symptoms -distended phagocyte cells = called Gaucher cells around found in: spleen, liver, bone marrow, lymph nodes, tonsils, thymus, Peyer’s patch. -Gauchers cells have fibrillary type of cytoplasm (look like crumpled tissue paper Gauchers Disease (see more details above) -Type 1: reduced but + levels of glucocerebroside activity Gauchers Type 2: Acute neuronopathic Gauchers infantile acute cerebral pattern Gauchers Disease (see more details above) NO detectable gluocerebroside activity in tissues -Common in Jews of European stock -Longevity is shortened and progressive in adults but is compatible with a long life -First appear in adult -Clinical symptoms: splenomegaly or bone involvement (splenic and skeletal) pancytopenia or thrombocytopenia due to hypersplenism, pathological fractures and bone pain due to expansion of marrow space No predilection for Jews -heptaosplenomegaly present but progressive CNS involvement is dominant leading to death at an early age. -Clinical symptoms: CNS abnormalities, convulsions, progressive mental deterioration, and affects organs such as: liver, spleen and lymph nodes Gauchers Type 3: Intermediate between Type 1 & 2 Gauchers Disease (see more details above) Systemic involvement Gauchers Type 1: Progressive CNS disease beginning in adolescence or early adulthood -Clinical symptoms: same as type 2: Disease Mucopolysaccharido ses (MPS) Description Accumulation of mucopolysaccharide are in mononuclear phagocytic cells, endothelial cells, intimal smooth muscle cells and fibroblast throughout the body. Group/Types There are types 1-7, each with a specific enzyme deficiency (so clinical picture is different for each type) Cause/Mutations Deficiency of lysosomal enzymes fro the degredation of mucopolysaccharides (glycosaminoglycans) which are long chain complex carbs linked to form proteoglycans (in connective tissues) -All are autosomal recessive (except Hunters syndrome = X-linked recessive) Info/Clinical symptoms -The glycosaminoglycans that accumulate in MSP are: dermatan sulfate, heparan sulfate, keratan sulfate, and chondroitin sulfate -The enzyme that degrade MPS cleave the terminal sugar from the polysaccharide chain diposed along a polypeptide or core protein -Common sites involved: spleen, liver, bone marrow, lymph nodes, blood vessels, and heart. -Clinical symptoms: hepatosplenomegaly, skeletal deformities, valvular lesions, subendothelial arterials (mainly in coronary arteries and the brain) can lead to coronary subendothelial lesion MI -Cardiac decompensation and MI are main causes of death Hurler syndrome MPS 1-H Type 1: Deficiency of a-IMucopolysaccari iduronidase doses (MPS deficiency) -One of the most severe forms of MPS -normal at birth develop heptosplenomegaly by age 6-24 y/o -Other clinical symptoms: growth retardation, coarse facial features, skeletal deformities -death occurs by age 6-10y/o mostly due to cardiovascular complications Hunter Syndrome MPS 2 Mucopolysaccari X-linked inheritance doses (MPS deficiency) Clinical symptoms: absence of corneal clouding and milder symptoms Disease Neuronal Ceroid Lipofuscinoses Description Accumulation of lipofuscin (autofluorescent substance with a variety of ultrastructural appearance in neurons) Group/Types Neuronal Storage Disease Cause/Mutations Inherited lysosomal storage disease Info/Clinical symptoms Clinical symptoms: blindness, mental and motor deterioration, seizure -Classified by age of onset: infantile (INCL), late infantile (LINCL), juvenile (JNCL) and adult neuronal ceroid lipofuscinoses (ANCL; Kuf disease) -Also can be classified by pattern of inclusions by electron microscopy Krabbe Disease Deficiency of galactosylceramidase is needed for catabolism of galactocerebroside cermaide and galactose (accumulation of galactocerebroside is NOT the direct toxic agent) -The alternate catabolic pathway removes the fatty acid from this molecule making galactosylsphingosine which IS cytotoxic causing oligodendrocyte injury Leukodystrophi es Autosomal recessive disease with deficiency of galactocerebroside Bgalactosidase (galactosylceramidase) -chromosome 14q31 -Clinical symptoms are dominated by motor signs: stiffness, weakness, with gradual worsening difficulties in feeding -Clinical course is rapidly progressing with onset between 2-6 mo -usually causes death prior to 2 y/o Metachromatic Leukodystrophy Arylsulfatase A which cleaves the sulfate from the sulfatecontaining lipid (sulfatide) in their degredation deficiency causes accumulation of sulfatides (especially cerebroside sulfate) Leukodystrophi es Autosomal recessive with deficiency of lysosomal enzyme: arylsulfatase A -Chromosome 22q -Clinical subtypes include: late infantile form (most common), juvenile form and adult form -Symptoms Child onset: motor symptoms which progress gradually with death in 5-10 yrs Adult form: initial symptoms are psychiatric or cognitive symptoms with motor symptoms coming later Disease Adrenoleukodystrop hy Description Progressive disease with myelin loss from the CNS, peripheral nerves and adrenal insufficiency Group/Types Cause/Mutations -X-linked form: earliest onset -Mutation of the ALD gene on chromosome Xq28 (which encodes the ATP binding cassette transporter family of proteins ABCD1) Info/Clinical symptoms Earlier onset have more rapid course: X-linked presents in school years with neuro symptoms and adrenal insufficiency and rapidly progressive fatal -later onset in adults: slowly progressing with PNS involvement developing over decades -There will be loss of myelin, gliosis and lymphocytic infiltration with atrophy of the adrenal cortex -inability to properly catabolize very-long-chain fatty acids (VLCFA) in peroxisomes with elevated VLCFA in serum -Mitochondrial Encephalomyopathy -Lactic Acidosis, -Strokelike episodes (MELAS) -These are common neurological syndromes -Characterized by recurrent episodes of acute neurological dysfunction, cognitive changes, muscle involvement with weakness and lactic acidosis Mitochondrial Encephalomyop athies -Mutation for MELAS: tRNA -Coding-gene mutations have also been seen -Most present as a muscle disease while second most common is CNS -Pathologically areas of infarction are seen with vascular proliferation and focal calcification Myoclonic epilepsy and ragged red fibers (MERRF) Syndrome that causes myoclonus (a seizue disorder) and evidence of myopathy Mitochondrial Encephalomyop haties Maternally transmitted disease -Also associated with tRNA mutation -Can also see ataxia due to neuronal loss of cerebellar system (inferior olive in medulla, cerebellar cortex and deep nuclei) Leigh Syndrome (Subacute Necortizing Encephalpathy) Syndrome that causes lactic academia, arrest of psychomotor development, feeding problems, seizures, extra-ocular palsies and weakness with hypotonia Mitochondrial Encephalomyop haties Diverse mutations affecting mitochondrial genome-encoded components of oxidative phosphorylation complexes -Also possibly mitochondrial tRNA mutations -Usually in early childhood -Death occurs within 1-2 yrs Disease Thiamine (Vit B1) deficiency Description -Can be associated with Beriberi and its associated cardiac failure Group/Types Acquired Metabolic Disease Usually called WernickeKorsakoff syndrome Vitamin B12 deficiency Causes anemia and potential irreversible effects on the nervous system Acquired Metabolic Disease Hypoglycemia Initially leads to selective injury to large pyramidal neurons of the cerebral cortex -If severe: result in pseudolaminar necrosis of the cortex Neurological Sequelae of Metabolic Disturbances Cause/Mutations Info/Clinical symptoms -Can lead to the development of psychotic symptoms or ophtalmoplegia Wernicke encephalopathy (but treatment with thiamine can reverse symptoms) -Acute stages due to prolonged, untreated deficiency may lead to Korsakoff syndrome memory disturbances and confabulation -Common in chronic alcoholism or individuals with gastric disorders like carcinomas, chronic gastritis or persistent vomiting -Neuro symptoms that occur within a few weeks = numbess, tingling and slight ataxia in LE but progress rapidly to spastic weakness in LE -Vitamin replacement can cause clinical improvement If complete paralegia occurs later in disease, recover is poor -Similar to O2 deprivation -Some areas of the brain more sensitive to hypoglycemia if severe enough can lead to widespread brain injury -Hippocampus is vulnerable showing loss of pyramidal neurons in Sommer sector (area CA1) -Purkinje cells of the cerebellum are sensitive but to lesser extent then hypoxia Disease Hyperglycemia Description Inadequately controlled diabetes mellitus and can be associated with ketoacidosis and hyperosmolar coma Group/Types Neurological Sequelae of Metabolic Disturbances Carbon Monoxide Hypoxia from O2-carrying capacity of hemoglobin Toxic disorders Methanol Affects the retina where degeneration of retinal ganglia cause blindess Chronic alcohol abuse: neurological sequelae including Wernicke-Korsakoff syndrome Toxic disorders Ethanol Toxic disorder Cause/Mutations Info/Clinical symptoms -Clinical symptoms: dehydration, development of confusion, stupor and eventual coma -fluid depletion must be corrected gradually or else severe cerebral edema will arise -Severe injury of neurons of layers 3 & 4 of cerebral cortex, sommer sector of hippocampus and Purkinje cells -Bilateral necrosis of the globus pallidus -Bilateral putamenal necrosis and focal white matter necrosis occur if exposure is severe -either due to direct or secondary nutritional deficits -cerebellar dysfunction can occur (1% chronic alcoholics) associated with clinical syndrome of truncal ataxia, unsteady gait and nystagmus Disease Tay-Sach’s Disease Description Inability to Catabolize GM2 Gangliosidosis Deficinecy of hexosaminidase A Neurons are ballooned with cytoplasmic vacuoles Common among jewish population Mutation α-Subunit locus on chromosome 15 Sandhoff Disease GM2 Activator deficiency Neimann-Pick Disease GM2 Gangliosidosis GM2 Gangliosidosis Lysosomal accumulation of sphingomyelin due to an inherited deficiency of spingomyelinase Β-subunit defect Type A NPD: Severe infantile form with neurologic involvement, visceral accumulations of sphingomyelin, and progressive wasting and early death . Type B NPD: Pts have ortanomegaly but not CNS involvement. Can survive into adulthood Type A: Missense mutation resulating in almost complete deficiency of sphingomyelinase. Chromosome 11p15.4 More than 100 mutations with a correlation between type of mutation and severity Clinical Accumulation of GM2 Gangliosidosis affects neurons in the CNS, ANS, and retina Normal at birth symptoms begin around 6months motor and mental deterioration including motor incoordination, blindness, muscular flaccidity Cherry red spot in macula Similar to clinical features of TaySach’s listed above Affected cells become enlarged with innumerable small vacuoles of uniform size are created giving cytoplasm a “foaminess” look. These cells are found in spleen, liver, lymph nodes, bone marrow, tonsils, GI and lungs. Brain gyri are shrunken and sulci widened. This effects are diffuse. Vacuolation and ballooning of neurons constitute histological change. Rtinal cherry-red spot is also occasionally present Type A: Symptoms may be present at birth to 6months. Infants have protuberant abdomen, which is followed by failure to thrive, vomiting, fever, lymphadenopathy. Death within1-2 years. Disease Description Mutation Gaucher Disease Accumulation of glucocerebrosides activating Mac, IL-1, IL-6, and TNF. Distended phagocytic cells Gaucher cells Type 1: Chronic nonneuronopathic form. Glucocerebrosides accumulate in mononuclear phagocytes. NO BRAIN INVOLVEMENT! Type 2: Acute neuropathic. Infantile acute cerebral pattern. No detectible glucocerebrosides. Type 3: intermediate between I and II Autosomal recessive disorder- mutation in gene encoding glucocerebrosidase Have types I-VII each resulting form the deficiency of one specific enzyme Accumulation of MPS are foundin mononuclear phagocytic cells, endothelial cells, intimal smooth muscle cells, and fibroblasts Hurler Syndrome: MPS 1-H. Deficiency of α-I-iduronidase. Severe form. Affects children 6-24 months Hunter syndrome: MPS II Autosomal X-linked Genetically determined deficiency of lysosomal enzymes involved in degradation of MPS Most autosomal recessive except Hunter syndrome Description Mutation Mucoploysachharideoses (MPS) Disease Clinical Type 1: Splenic and skeletal involvement dominate. Longevity not markedly decreased . Symptoms appear in adult life Type 2: Hepatospelnomegaly. Progressive CNS involvement. Convulsions and progressive mental deterioration. Death at an early age Type 3: Systemic involvement but no progressive CNS disease. Usually begins in adolescence or early adulthood. Hepatosplenomegaly, skeletal deformities, valvular lesions, and subendothelial arterial deposits Hurler Syndrome: Growth is retarded, coarse facial features, and skeletal deformities. Death by 6-10 due to cardiovascular problems Hunter Syndrome: absence of corneal clouding. Milder clinically Clinical Schwannoma Benign tumor arises form neural crest derived Schwann cells. Common component of Neurofibromatosis 2 Well circumscribed, ecapsulated, easily separated form nerve Neurofibroma Present as discrete localized masses. Most commonly cutaneous or in a peripheral nerve as solitary neurofibroma The presence of multiple of plexiform neurofirboma suggest diagnosis of neurofibromatosis type 1 (NF1) Plexiform Neurofibroma: result in significant neurologic deficit. Difficult to remove and significant potential for malignant transformation Malignant Peripheral Nerve Sheath Tumor Disease Highly malignant that are locally invasive, frequently recurrent and spread. Commonly in medium or large nerves 50% arise from plexiform neurofibroma or radiation Description Inactivatin mutation in NF2 gene on chromosome 22. Resulting in the loss of merlin product Cells then hyperproliferate because merlin is no present to restrict expression of GFR Compression of involved nerve or adjacent structures. Commonly cerebellopontine angle presenting with tinnitus and hearing loss (acoustic neuroma, CN 8) Histologically: Antoni A- elongated cells with cytoplasmic processed arranged in fascicles. Verocay bodies are the “nuclear free zones” Antoni B timor is less densely cellular consisting of loose meshwork of cells Skin lesions grow nodules sometimes overlying hyperpigmentation. Mostly cosmetic very little risk of these becoming malignant. Alteration in both copies of NF1 gene have been observed in Schwann cell component of plexifrom neurofribromas supporting critical role for loss of NF1 function which is to produce neurofirbomin that stimulate GTPase that inhibits RAS May arise anywhere along a nerve. Affected nerves are irregularly expanded as each fascicle is infiltrated by neoplasm. No possible to separate lesion from nerve. Lesion is loose, myxoid background with low cellularity. Schwann cells, multipolar fibroblastic ells, inflammatory cells, and axons are all present in tumor NF1 function is lost and subsequent alteration often disrupt p-53 and Rbdependent pathways for regulating cell proliferation Mutation Clinical Neurofibromatoses (Von Recklinghausen Disease) Neurofibroma, gliomas or optic nerve, pigmented nodules of iris (Lisch nodules) and cutaneous hyperpigmented macules (café au lait spots) Autosomal dominant Type 1 (NF1): Proprensity for plexiform neurofibromas to undergo malignant degeneration at higher rate than comparable tumors Type 1: Course is highly variable some have no symptoms other develop progressive disseae with spinal deformities, disfiguring lesions, and compression of vital structures. Type 2 (NF2): Range of tumors commonly bilateral eight nerve schwannomas and multiple meningiomas. Non neoplastic lesions including nodular ingrowth of Schwann cells to spinal cord, meningioangiomatosis and glial harmartia Disease/ Injury Description MOI Symptoms Diastic Skull fracture Kinetic energy from fracture dissipated to fused suture. This type is when it crosses the suture Displaced Skull fracture The bone is displaced into cranial cavity by distance greater than bone thickness Linear Skull fracture Branching fracture radiating out Fall and hit head on hard surface from main fracture line Majority are this type! Basilar skull fracture Fracture of the base of the skill Follows impact to occiput or side of head (MVA) Symptoms can be referred to lower cranial nerves or cervicomedullary region, presence of orbital or mastoid hematomas can also be present. CSF may discharge from nose or ear. Ring Fracture Fracture that encircles or nearly encircles the foramen magnum Concussion Clinical syndrome of altered consciousness Head forcibly pushed inferiorly into vertebral column or visa versa EX: someone jump from great high and land on feet Head injury brought on by change in momentum Contusion DIRECT PARENCHYMAL INJURY Blow to surface of brain leading to rapid tissue displacement, disruption of vascular channels, hemorrhage, and edema (Crest of gyri most susceptible) Getting hit in head with hammer Instant onset of transiet neurological dysfunction, LOC, loss of reflexes, temporary respiratory arrest Typically happens when head is mobile at Coup Injury: Develops a contusion time of injury at point of contact Countrecoup Injury: Contusion on brain surface diametrically opposite to point of contact Usually after sudden deceleration Disease/ Injury Diffuse Axonal Injury Description Axonal swelling. Mechanical force assoc with trauma damage integrity of axon at node of Ranvier Wearing of an artery extravasation of blood under arterial pressure can cause dura to separate from inner surface of skull MOI Angular acceleration (even in absence of impact) or hemorrhage Symptoms Injury greatest where density difference is greatest. Many indv. w/ coma have this injury Injury to dural arteries most commonly the middle meningeal artery. Commonly injured in temporal skull fractures Expanding hematoma compress brain and can expand rapidly— emergency requiring drainage Subdural Hematoma Between inner surface of dura and outer arachnoid layer Bridging veins traveling from cerebrum though dura and arachnoid to empty into sinus can be torn @ point where they penetrate dura during trauma Usually manifest within 48hours of injury normally over lateral aspects of brain. Non-localizing headaches and confusion are common along with slowly progressing deterioration. Common in elderly patients even with mild trauma Gunshot Wound Entrance Wound: Usually round with associated marginal abrasion Exit Wounds: Typically tear skin and have irregular margins Contact Gunshot Wound: Associated with muzzle stamp or soot Close Range: Soot and searing of skin Medium Range: Some soot stippling around entrance wound Distance Range: No gunpowder or other defect of the skin associated with entrance wound Child Abuse Child with head trauma Post Traumatic Hydrocephalus Build up of CSF around brain Epidural Hematoma “Shaken baby syndrome” Scalp contusions, subdural hematoma or blood, perioptic nerve or retinal hemorrhages Due to obstruction of CSF resportion from hemorrhage into subarachnoid space Post Traumatic Dementia Follow repeated head trama during and Punch drunk Syn protracted period Post Traumatic Epilepsy, tumors, infection, diseases, and psychiatric disorders can also follow head trauma Disease/ Injury Spinal Cord Trauma Description MOI Segmental damage to descending and ascending white matter isolates distal cord from CNS connections Symptoms Above C4 Resp compromise Cervical Lesions Quadriplegia Thoracic and below Paraplegia Vasogenic Edema Increased CSF volume Caused by BBB disruption and increased vascular permeability allowing fluid to shift form intravascular compartment to intercellular space of brain Can be localized or generalized Cytotoxic Edema Increased CSF volume Interstitial Edema (hydrocephalic edema) Increased CSF volume Increase in intracellular fluid 2ndary to neuronal, glial, or endothelial cell membrane injury Increase in intravascular pressure causes abnormal flow of fluid from intraventricular CSF across ependymal lining to periventricular white matter Common in patients with generalized hypoxic/ischemic insult or with metabolic disease Occurs especially around lateral ventricle Generalized Edema Gyri are flattened, Sulci are narrowed, and ventricular cavities are compressed. As brain expands herniation may occur Accumulation of excessive CSF within ventricular system increases volume of ventricles and expands them increasing intracranial pressure Communicating: enlargement of all ventricular sytem Non –Com: Only portion of ventricular system is enlarged (usually mass in 3rd ventricle) Impaired flow and resorption or overproduction of CSF Infancy Enlarged head (increased circumference) After Infancy Expansion of ventricles and increased pressure without change in head circumference Hydrocephalus Hydrocephalus ex vacuo: dilation of ventricular system with ↑ in CSF volume 2ndary to loss of brain parenchyme Disease/ Injury Description MOI Symptoms Increased Intracranial Pressure Volume of brain increases beyond limit permitted by compression of veins and displaced CSF Associated with diffuse brian edema or focal effect (Tumor, abscesses, or hemorrages) Can lead to herniation Syndrome Subfalcine (cingulate): Unilateral expansion of cerebral hemisphere that displaces cingulate gyrus. Compression branches of Ant. Cerebral a. Transtentorial: Medial aspect of temporal lobe is compressed against free margin of tentorium. CN 3 compromised: pupillary dilation and impaired ocular movement (ipsilateral side). Post Cerebral a. compressed: ischemic injury, impairing visual cortex. Contralateral cerebral peduncle may also be compressed resulting in ipsilateral hemiparesis known as Kernohan’s notch Lesions to the midbrain and pons are also commonly present and termed secondary brainstem or Duret hemorrhages Tonsillar Herniation: Displacement of cerebellar tonsills through foramen magnum. Life threatening because of compression placed on brainstem and vital respiratory and cardiac centers in medulla