CNS Diseases Presentation PDF

‫بسم هللا الر حمن الر حيم‬ ‫‪DISEASES OF THE CNS‬‬ Why the nervous system differs than the other systems ??? ◼ 1. Every part of brain perform specialized function. ◼ 2. The brain substance is composed of -neurons( nerve cells and nerve fibers) - supporting glial cells a. Astro...

‫بسم هللا الر حمن الر حيم‬ ‫‪DISEASES OF THE CNS‬‬ Why the nervous system differs than the other systems ??? ◼ 1. Every part of brain perform specialized function. ◼ 2. The brain substance is composed of -neurons( nerve cells and nerve fibers) - supporting glial cells a. Astrocytes (support) b. Oligodendrocytes (nutritive ) c. Microglial cells (macrophages)  Neurodegenerative diseases ◼ progressive loss of neurons, typically affecting groups of neurons with functional interconnections. ◼ Involve the hippocampus and cortices, present with cognitive changes (memory, behavior, and language). Alzheimer disease. ◼ Affect the basal ganglia manifest as movement disorders; (hypokinetic e.g. Parkinson disease),( hyperkinetic e.g. Huntington disease). ◼ Affect the cerebellum (ataxia ) ◼ The motor system (difficulty with swallowing and respiration) ◼ A pathologic process shared by most neurodegenerative diseases is the accumulation of protein aggregates, ◼ Alzheimer disease (AD) is the most common cause of dementia in older adults, with an increasing incidence as a function of age. ◼ accumulation of two proteins (Aβ and tau) result in secondary effects including neuronal dysfunction, neuronal death, and inflammatory reactions. ◼ Parkinson disease (PD) is a neurodegenerative disease marked by a hypokinetic movement disorder that is caused by loss of dopaminergic neurons from the substantia nigra. ◼ tremor, rigidity, bradykinesia, and instability.  Increases Intracranial pressure ◼ 1.Definition Increased CSF pressure more than 15 mmHg (200mm water), measured with the patient in the lateral decubitus position clicnial symptom Causes: - Projectile vomiting 1.Space occupying lesions - Headache - Papillaedema 2.Cerebral edema - Decreased Level of 3.Obstructive hydrocephalus Consciousness  MENINGITIS ◼ It is inflammation of : - Leptomeninges of brain & spinal cord. - Subarachnoid space ◼ * Types : 1. Acute Pyogenic meningitis (Bacterial). 2. Acute lymphocytic meningitis (Viral/TB). 3. Chronic meningitis (Bacterial, Fungal).  Routes of infection 1.By blood: most common. 2.Direct implantation  MENINGITIS 1. Acute pyogenic meningitis: ◼ * Causative organisms: ◼E. coli: in neonates. ◼ H. influenzae : in infants & children. ◼ N. meningitides : in adolescence & young adults. ◼ Pneumococcus: very young & old.  Clinical pictures ◼ General signs of infection :in stage of septicaemia ◼ Severe constitutional symptoms. ◼ Signs of infection (fever,malaise,rigor….) ◼ Profuse peticheal eruption. ◼ Signs of meningeal irritation: 1.Headache 2.Neck stiffness 3.Photophobia 4.Irritability  Complications of meningitis Spread of infection healing 1. To the ventricles 1. Fibrosis … obstruction of CSF 2. To Sub &extra dural spaces pathway …Hydrocephalus 3. Thrombophlebitis 2. Compress … Cranial nerve 4. Arthritis. palsy 3rd , 5th Otitis Media 3. Endarteritis obliterans ….Brain Endocarditis. infarcts conjunctivitis  Brain Abscess ◼ 1) Definition : Localized area of suppuration of brain tissue. ◼ 2) Routes of infection : ◼. Direct implantation (Traumatic).. Local extension (ex. maostoiditis).. Haematogenous (e.g from Bac. endocarditis). ◼ 3) Organisms: Staph aureus, Strept, Pneumoc. E.Coli  CNS trauma ◼ Epidural hematoma ◼ Subdural hematoma ◼ Traumatic parenchymal injuries 1. Concussion 2. Diffuse axonal injury 3. Contusion  Concussion ◼ Definition transient loss of consciousness following head trauma ◼ widespread paralysis, seizures ◼ loss of memory about the trauma ◼ Complete recovery over hours to days ◼ no anatomic lesion  Hydrocephalus ◼Definition Abnormal dilatation of ventricular system by excess cerebrospinal fluid with atrophy of the brain tissue. ◼ Types: ◼ (1) Communicating hydrocephalus: ◼ (2) Non-communicating hydrocephalus: * General features of primary brain tumors ◼ Benign tumours : Fatal if in a critical position. ◼ Usually infiltrative : Curative resection is impossible. ◼ Rarely metastasize. Can spread through C.S.F Clinicopathological effects of tumors 1- Local effects: -Neurologic deficits depending on : Site and Size. 2- Increasing occupation of Limited space Lead to Increase ICP :which manifested by Headache Increase Vomiting intracranial BP papilloedema Stupor coma Death Tumors of the nervous system ◼ I. Primary parenchymal Tumors ◼ II.Primary non – parenchymal Tumors ◼ III. Metastatic Tumors  Tumors of the nervous system I. Primary parenchymal Tumours: a- Tumours of neuroglia (Gliomas). * Astrocytes: * Oligodentrocytes: * Ependymal cells: ex  Tumors of the nervous system II. Primary non – parenchymal Tumors: ◼ a. Tumors of meninges. * Meningioma. , Meningeal Sarcoma. ◼ b. Tumors of nerve sheath cells. * Schwannoma. Neurofibroma. ◼ c. Pituitary tumors. ◼ d. Malformative turmors. * Craniopharyngioma. * Epidermoid & dermoid cysts. III. Metastatic Tumors Primary non – parenchymal Tumors: Meningioma ◼ Tumors of meninges ◼ Develops from the meningothelial cells of the arachinoid, therefore the tumor arises outside the brain. ◼ It represent 20% of primary brain tumors.  Meningioma ◼ Usually occurs in middle and later life. ◼ Female : Male = 3:2. ◼ It usually arises in : Front half of the cranial cavity. (Hemispheric convexity).  Metastatic tumors ◼ Represents 25-30% of brain tumors. ◼ They are mostly metastasis from: ◼ Lung. ◼ Breast. ◼ Skin (melanomas). ◼ Kidney. ◼ Gastrointestinal tract. ◼ N.B.: Choriocarcinoma although rare metastasize to the brain.  Metastatic tumors ◼ Gross: Multiple. Well circumscribed masses. Spherical. Located at the cortex-white matter junction. Are surrounded by a zone of edematous white matter. ◼ M.P. Mostly resembles their primary tumor.