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Migraine A recurrent primary headache disorder characterized by episodic throbbing headaches, usually unilateral, lasting 4–72 hours. Often associated with nausea, vomiting, photophobia, phonophobia, and sometimes preceded by aura. Classification of Migraine Main Types: Migraine Without Aura (Common migraine) Migraine With Aura (Classic migraine) Subtypes: Migraine Without Aura: Episodic, Chronic, Menstrual, Vestibular. Migraine With Aura: Typical aura with/without headache, Migraine with brainstem aura, Hemiplegic migraine (familial/sporadic), Retinal migraine. Complications: Status migrainosus ($>72$ hours), Persistent aura without infarction, Migrainous infarction, Migraine-triggered seizure. Probable Migraine: Symptoms not fulfilling complete diagnostic criteria. Episodic vs. Chronic: Episodic ($ Pathophysiology Cortical Spreading Depression (CSD): Main mechanism of aura. Ion channel dysfunction $\rightarrow$ excitation, then hyperpolarization/suppression. Wave spreads across cortex at $\sim3$ mm/min. Vascular Changes: Headache corresponds to vasodilation of extracranial vessels. Hypothalamic activation modulates pain pathways. Trigeminovascular System Activation: Trigeminal nerves release CGRP, substance P $\rightarrow$ vasodilation, neurogenic inflammation, pain signals. Genetic Factors: Migraine often runs in families. Linked to specific ion channel mutations in rare forms (e.g., hemiplegic migraine). Hormonal Influences: Female predominance. Attacks often around menstruation (fall in estrogen). Estrogen-containing OCPs may worsen migraine and slightly increase stroke risk with aura. Triggers: Often overrated. Psychological stress plays a stronger role (e.g., post-stress let-down like Friday evening headaches). Migraine Treatment 1. General & Trigger Avoidance Identify and avoid personal triggers (stress, sleep disruption, foods like chocolate/cheese/red wine). Avoid combined oral contraceptive pill in some cases. Maintain good sleep hygiene, regular meals/hydration. Avoid analgesic overuse (risk of medication-overuse headache). 2. Acute Treatment A. Simple Analgesics (First Line) Drug Dose Notes Aspirin 600–900 mg PO at onset Repeat after 4–6 hours Paracetamol 1 g PO Max 4 g/day NSAIDs (e.g., ibuprofen) Ibuprofen 400–600 mg, Naproxen 500–750 mg B. Antiemetics (For nausea + help analgesic absorption) Drug Dose Notes Metoclopramide 10 mg PO/IM/IV Useful as adjunct C. Triptans (5-HT1B/1D agonists) (If analgesics do not work) Drug Dose Route Sumatriptan 50–100 mg PO (first-line triptan) 6 mg SC (fastest action) 20 mg Intranasal (for vomiting) Rizatriptan 10 mg PO (may repeat after 2 hours) Zolmitriptan 2.5–5 mg PO (also intranasal) Caution: Avoid in coronary artery disease, pregnancy, uncontrolled hypertension. D. What to Avoid Any analgesic if used $>10-15$ days/month ($\rightarrow$ medication overuse headache). Ergotamine (risk of dependence, vasospasm). 3. Prophylactic Treatment (Indicated if $>2$ attacks/month or severe disability) A. Beta Blockers Drug Dose Propranolol 40 mg BID, titrate up to 160 mg/day Metoprolol 25-100 mg BID B. Antidepressants Drug Dose Notes Amitriptyline 10–25 mg at night, increase up to 50–75 mg Good in comorbid insomnia C. Antiepileptics Drug Dose Notes Topiramate 25 mg nightly $\rightarrow$ titrate to 50–100 mg BID Causes weight loss, paresthesia Sodium Valproate 400-600 mg BID Avoid in pregnancy D. Special Note Women with aura should avoid estrogen-containing OCPs and HRT. Cluster Headaches (Trigeminal Autonomic Cephalalgias - TACs) Severe unilateral headache. Characterized by clusters (bouts) of repeated attacks at the same time each day. Male predominance (M $\gg$ F). Onset: 3rd decade. Strong association with smoking and alcohol use. Pathophysiology Exact cause unknown. Features suggest a different mechanism from migraine. Functional imaging: Hypothalamic activation (especially posterior hypothalamus). Triggers: alcohol during cluster period. Patients often have higher smoking rates. Clinical Features Pain: Severe, unilateral, periorbital/temporal. Duration 30–90 minutes. Occurs 1–8 times/day. Often wakes the patient from sleep ($\rightarrow$ "alarm clock headache"). Autonomic Symptoms (ipsilateral): Tearing (lacrimation), nasal congestion/rhinorrhoea, conjunctival injection, ptosis + miosis (partial Horner syndrome), facial sweating. Behaviour: Patient is agitated, restless, may pace around (unlike migraine patients who prefer to lie still). Course: Occurs in clusters lasting weeks, followed by remission for months–years. Small group $\rightarrow$ chronic cluster headache. Management A. Acute Treatment (Abortive) 100% Oxygen inhalation: 100% O$_2$ at 12 L/min via non-rebreather mask. Often aborts attack within 10–15 minutes. Subcutaneous Sumatriptan: 6 mg SC $\rightarrow$ most effective. Onset within 5–10 mins. Nasal triptans less effective but may help. Note: Oral therapies (NSAIDs, oral triptans) are too slow for cluster headaches. B. Preventive Treatment (Prophylaxis) (Used during the cluster period) Verapamil (first-line): 120–240 mg/day, can be increased under ECG monitoring. Most effective long-term preventive therapy. Sodium Valproate: Useful in some patients. Short course of Oral Steroids: Prednisolone 40–60 mg/day, tapered over 2–3 weeks. Often rapidly breaks a cluster cycle. Lithium carbonate: Used in chronic cluster headache. Requires serum level monitoring. Trigeminal Neuralgia (Tic Douloureux) A condition causing recurrent, unilateral, brief, shock-like (lancinating) facial pain. Involves 2nd (maxillary) and/or 3rd (mandibular) branches of trigeminal nerve. Typically occurs in age $>50$ years. Often due to irritative compression of trigeminal root zone by an aberrant arterial loop. Clinical Features Pain Characteristics: Sudden, severe, stabbing, electric shock–like. Duration: seconds (very brief). Occurs in paroxysms with pain-free intervals. Triggers: Touch, shaving, brushing teeth, cold wind, eating or talking. Location: Unilateral, in V2 or V3 dermatomes. Physical signs: Usually absent. Patient may sit still with facial grimace during spasms ("tic douloureux"). Course: Remitting–relapsing over years. Rare variant: Cluster–Tic syndrome (features of cluster headache + trigeminal neuralgia). Parkinsonism Degenerative, progressive disease affecting the basal ganglia. Syndrome consisting of a variable combination of tremor, rigidity, bradykinesia, and a characteristic disturbance of gait and posture. Pathology Hallmark features of PD are degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc), reduced striatal dopamine, and intraneuronal proteinaceous inclusions in cell bodies and axons that stain for $\alpha$-synuclein (known as Lewy bodies and Lewy neurites; collectively as Lewy pathology). Clinical Features A. Motor Features Tremor: Resting, 3–4 Hz, “pill-rolling.” Asymmetric onset. Affects limbs, jaw, chin; never head. Bradykinesia: Fundamental feature. Slowness, reduced amplitude, fatigability. Micrographia. Difficulty initiating movement (gait ignition failure). Rigidity: Cogwheel rigidity (due to tremor + rigidity). Lead-pipe rigidity. Postural & Gait Abnormalities: Stooped posture. Loss of postural reflexes $\rightarrow$ falls. Festinant gait (short, rapid steps). Freezing in doorways. B. Non-Motor Features Cognitive impairment, dementia. Anxiety, depression, apathy. Hallucinations/psychosis. Sleep disturbance & hypersomnolence. Constipation, sexual dysfunction, drooling, weight loss. Autonomic symptoms. Investigations Diagnosis is clinical. A. Imaging: CT/MRI usually normal for age $\rightarrow$ rarely helpful. Used only to support suspected alternative causes (e.g., vascular parkinsonism). B. Functional imaging: SPECT/PET shows reduced dopaminergic activity early. Does not differentiate PD from atypical degenerative parkinsonism. C. Targeted tests in young patients: Wilson’s disease, Huntington’s, Genetic testing if family history. Management Diagnosis clinical [TRAP-tremor at rest, rigidity, akinesia, postural instability] $\rightarrow$ imaging if atypical. Start treatment when disability begins. Drug treatment for PD remains symptomatic rather than curative. Initial Choice $>60$ yrs / severe $\rightarrow$ Levodopa. $ Very mild $\rightarrow$ MAO-B inhibitor. If wearing-off $\rightarrow$ add Entacapone $\rightarrow$ DA agonist $\rightarrow$ MAO-B inhibitor. If dyskinesias $\rightarrow$ Amantadine. If tremor-dominant $\rightarrow$ Trihexyphenidyl (young only). Refractory symptoms $\rightarrow$ Deep Brain Stimulation. Non-motor symptoms $\rightarrow$ symptomatic management, Rivastigmine for dementia. Rehab: Physiotherapy, OT, Speech therapy. Never stop PD drugs abruptly. Step-by-Step Approach Confirm Diagnosis: Clinical diagnosis: bradykinesia + rigidity/tremor. Exclude atypical features (early falls $\rightarrow$ PSP, early autonomic failure $\rightarrow$ MSA). Imaging only if atypical/vascular cause suspected. Decide When to Start Treatment: Initiate treatment when symptoms impact everyday life. Choose Initial Drug: Age $>60$ OR prominent functional disability: Start LEVODOPA (most effective & best-tolerated). Combine with DDI (carbidopa/benserazide). Age $ Dopamine Agonist (Ropinirole / Pramipexole / Rotigotine). Mild early disease OR patient preference: MAO-B inhibitor (Selegiline / Rasagiline). If Symptoms Persist / Wearing-Off Occurs: Add COMT inhibitor (Entacapone) with each LD dose (improves motor fluctuations). Add Dopamine agonist (if patient started on levodopa only). Add MAO-B inhibitor (mild symptomatic extension). For Dyskinesias $\rightarrow$ Add Amantadine. Manage Specific Symptom Patterns: Tremor-dominant: Add anticholinergic (trihexyphenidyl, orphenadrine) $\rightarrow$ use only in young; avoid in elderly. Early morning akinesia / nocturnal symptoms: Controlled-release (CR) levodopa at night. Or dispersible Madopar for faster onset. Wearing-off during day: Increase dose frequency. Add entacapone, MAO-B inhibitor, or dopamine agonist. Treat Non-Motor Symptoms: Cognitive impairment/dementia: Rivastigmine (only drug licensed for PD dementia). Psychiatric symptoms: Reduce dopaminergic load. Avoid typical antipsychotics. Autonomic dysfunction: Constipation $\rightarrow$ laxatives. Drooling $\rightarrow$ speech therapy. Sleep problems: Sleep hygiene $\pm$ medication. Refer to Physiotherapy, OT, and Speech Therapy: Improves posture, rigidity, gait; helps dysphagia, communication. Medically Refractory Disease $\rightarrow$ DBS: Indications: Severe tremor, motor fluctuations, dyskinesias despite optimal drugs. Targets: Subthalamic nucleus, Globus pallidus, Thalamus. Ongoing Monitoring: Avoid abrupt withdrawal of PD drugs $\rightarrow$ risk of malignant hyperthermia-like syndrome. Movement Disorders Disorders of movement divide broadly into two categories: hypokinesias (slowed movements with increased tone - parkinsonism) and hyperkinesias (excessive involuntary movements). Chorea Irregular, semipurposeful, abrupt, rapid, brief, jerky and unsustained movements that flow randomly from one part of the body to another. These movements disappear during sleep. When choreic movements are more severe, assuming a flinging, sometimes violent, character, they are called ballism. Sydenham’s Chorea (St. Vitus Dance) Most common cause of chorea in children. Self-limiting, autoimmune complication of Group A $\beta$-hemolytic streptococcal (GABHS) pharyngitis. Appears 4–6 months after acute rheumatic fever (ARF). Course is variable; usually lasts weeks to months. Pathophysiology: Trigger: GAS pharyngitis $\rightarrow$ autoimmune response. Molecular mimicry: streptococcal antigens resemble CNS antigens. Leads to production of cross-reactive antibodies that target basal ganglia. Inflammation of caudate nucleus demonstrated. Clinical Features: Neurological: Chorea, muscle weakness & hypotonia, motor impersistence (inability to sustain motor acts), dysarthria, poor fine motor control. Worsens with stress, disappears during sleep. Psychiatric / Behavioral: Emotional lability, hyperactivity, distractibility, obsessions/compulsions, anxiety, irritability. Impact on ADL: Difficulty with eating, talking, writing, dressing, walking, learning and social interactions. Investigations: ASO titres and ESR often normal. Evaluation for valvular heart disease is mandatory. Treatment: Symptomatic Treatment of Chorea: First-line: Sodium Valproate (200–600 mg TID). If inadequate: Risperidone (1 mg BID, increase to 2 mg BID). Other options: Haloperidol, Pimozide, Carbamazepine, Clonidine, Phenobarbital. Secondary Prevention: Penicillin prophylaxis is essential. Prognosis: Generally self-limiting. Psychiatric symptoms may persist longer. Huntington’s Disease (HD) Autosomal dominant, trinucleotide repeat disorder. Etiology & Genetics: Caused by CAG trinucleotide repeat expansion in the Huntingtin (HTT) gene on chromosome 4. Shows anticipation. Clinical Features: HD has 3 major domains: Behavioural / Psychiatric: Irritability, impulsivity, depression, anxiety, personality change, social withdrawal. Psychosis may occur later. Motor Symptoms: Chorea, dystonia, gait abnormalities, motor impersistence. Juvenile onset ($ Cognitive Decline: Progressive cognitive impairment, executive dysfunction, eventually dementia. Investigations: Genetic testing: Definitive diagnosis (detects HTT gene CAG repeat expansion). Imaging: MRI/CT may show caudate nucleus atrophy (not diagnostic). Management: No cure $\rightarrow$ symptomatic and supportive. Motor symptoms (Chorea): Risperidone, Sulpiride, Tetrabenazine. Psychiatric symptoms: SSRIs for depression, anxiolytics for anxiety, atypical antipsychotics for psychosis. Cognitive decline: Supportive therapy, safety supervision, occupational therapy. Multidisciplinary care: Physiotherapy, OT, Speech therapy, Nutritional support, Social support and counselling. Family counselling: Essential due to autosomal dominant inheritance. Athetosis Slow, writhing, continuous, involuntary movements, usually affecting the distal limbs (fingers, hands, toes, feet). Often described as “snake-charmer” or serpentine” movements. Causes: Kernicterus, degenerative brain disorders (basal ganglia), cerebral palsy (athetoid CP), encephalitis, thalamic stroke. Treatment: Haloperidol, Tetrabenazine. Myoclonus A brief, rapid ($ Types: Spontaneous, action, reflex, physiologic (hypnagogic jerks), negative (asterixis). Treatment: Correction of underlying disease. Sodium valproate, Clonazepam. Tardive Dyskinesia (TD) Medication-induced hyperkinetic movement disorder. Caused by prolonged use of dopamine receptor–blocking agents (DRBAs). Movements are involuntary, may be choreiform, dystonic, or stereotyped, and can persist or even worsen after stopping the drug. Etiology / Causative Drugs: Antipsychotics (first-generation, second-generation), antiemetics (metoclopramide, prochlorperazine). Clinical Features: Chorea, athetosis, akathisia, stereotypies, dystonia, tics, respiratory dyskinesias. Orofacial Dyskinesias (Most Characteristic): Tongue protrusion or twisting, lip pouting/puckering/smacking, chewing movements, bruxism, blepharospasm. Worsen with stress, decrease during sleep. Course: Often persists after stopping the offending drug. May be irreversible. Treatment: VMAT2 inhibitors (first-line) $\rightarrow$ Tetrabenazine, Valbenazine, Deutetrabenazine. Motor Neuron Disease (MND) A neurodegenerative disorder characterised by progressive loss of upper motor neurons (UMN) in the motor cortex and lower motor neurons (LMN) in the brainstem and spinal cord. Peak onset after age 50. More common in males. 90% sporadic, 10% familial. Pathophysiology Degeneration of UMN ($\rightarrow$ corticospinal tract degeneration) and LMN ($\rightarrow$ anterior horn cells + cranial nerve motor nuclei). Produces combined UMN + LMN signs with no sensory deficit. Clinical Features Onset: Usually $>50$ years. Male predominance. Symptoms: Limb muscle weakness, cramps, fasciculations, dysarthria & dysphagia (bulbar involvement). No sensory symptoms. Behavioural/cognitive changes (FTD-like). Signs: Lower motor neuron signs: Muscle wasting, fasciculations, weakness (limbs, face, tongue, palate). Upper motor neuron signs: Spasticity, exaggerated tendon reflexes, extensor plantar responses. Other key points: Extraocular muscles and sphincters are usually spared. No objective sensory loss. Course: Starts focally $\rightarrow$ spreads relentlessly and progressively. Combination of UMN + LMN signs in same region is characteristic. Investigations Clinical diagnosis: Typical features (combined UMN + LMN signs, no sensory loss). Exclusion of mimics: Essential to rule out treatable alternatives (e.g., multifocal motor neuropathy, cervical myeloradiculopathy). EMG: Widespread denervation + reinnervation. Nerve conduction studies: Normal sensory conduction. Motor amplitude reduced (axonal loss). Creatine kinase: Mild/moderate elevation possible. Imaging: MRI spine/brain to exclude structural lesions. Genetic testing: Useful when family history present. Management Multidisciplinary Care is Essential (physiotherapy, speech therapy, etc.) A. Disease-Modifying Therapy: Riluzole (glutamate release antagonist) $\rightarrow$ prolongs survival by 2–3 months. B. Respiratory Support: Non-invasive ventilation (NIV) $\rightarrow$ most effective supportive treatment. C. Feeding Support: Percutaneous gastrostomy $\rightarrow$ improves nutrition. D. Symptom Management: Spasticity $\rightarrow$ baclofen, tizanidine. Sialorrhoea $\rightarrow$ glycopyrrolate, botulinum toxin. Cramps $\rightarrow$ quinine sulphate. Depression/anxiety $\rightarrow$ SSRIs. Pseudobulbar affect $\rightarrow$ dextromethorphan–quinidine. E. Palliative Care: Should be introduced early. Meningitis Acute infection of the meninges presents with a characteristic combination of pyrexia, headache and meningism. Meningism consists of headache, photophobia and stiffness of the neck, often accompanied by other signs of meningeal irritation, including Kernig’s sign and Brudzinski’s sign. Meningism is not specific to meningitis. Bacterial Meningitis / Pyogenic M. / ABM An inflammation of the leptomeninges (arachnoid and pia), and fluid residing in the space that it encloses and also that in the ventricles of the brain. In India $\rightarrow$ H. influenzae type B & Strep. pneumoniae most common. Pathogenesis: Nasopharyngeal invasion $\rightarrow$ bloodstream $\rightarrow$ meninges. Immune reaction $\rightarrow$ pia–arachnoid congested & infiltrated. Pus forms in layers, later forming adhesions. Adhesions cause: Obstruction of CSF flow $\rightarrow$ hydrocephalus, cranial nerve palsies, hearing loss. CSF: Rapidly $\uparrow$ pressure, $\uparrow$ protein, neutrophilic reaction. Leptomeningeal endarteritis $\rightarrow$ cerebral infarction. Pneumococcal meningitis $\rightarrow$ very purulent CSF, high mortality in elderly. Clinical Features: Typical: Headache, fever, neck stiffness, drowsiness, photophobia, vomiting. Severe infection: Coma, seizures, focal neurological deficits. Meningococcal meningitis: 90% have $\ge2$ of: Fever, neck stiffness, altered consciousness, rash (petechial/purpuric). Mortality doubles if presenting with sepsis. Pneumococcal and Haemophilus meningitis often coexist with otitis media. Listeria affects pregnant women, diabetics, alcoholics, immunosuppressed patients and neonates. Investigations: Lumbar puncture is essential but defer if signs of raised ICP. If LP deferred, blood cultures and empirical antibiotics started immediately. In bacterial meningitis CSF is cloudy with high neutrophils ($>1000 \times 10^6$/L), elevated protein, and low glucose; Gram stain, culture, and PCR help identify the pathogen. Management: Give parenteral benzylpenicillin immediately (IV route preferred). Immediate hospital admission AND Empirical therapy (Cefotaxime or ceftriaxone $\pm$ vancomycin $\pm$ ampicillin). Steroids reduce hearing loss and neurological sequelae. Meningococcal sepsis doubles mortality and may cause shock, DIC, ARDS. ICU care if needed. Poor prognosis: shock, rapidly spreading rash, DIC, multisystem failure, age $>60$. Prevention: Close contacts get rifampicin or ciprofloxacin. Vaccines available. TB Meningitis Tuberculosis (TB) is caused by infection with Mycobacterium tuberculosis (MTB). Pathophysiology: Typically appears shortly after primary infection in childhood OR as part of miliary tuberculosis. Local source of infection (caseous focus in meninges or brain tissue) $\rightarrow$ rupture releases bacilli into CSF. Meningeal pathology: greenish, gelatinous exudate (especially around brain base), small tubercles along meninges. Produces: cranial nerve palsies, hydrocephalus, cerebral infarcts due to arteritis. Investigations: Lumbar Puncture: CSF shows increased pressure, usually clear appearance, "spider-web" fine clot may form. Cells: Up to $500 \times 10^6$/L, mainly lymphocytes, may include neutrophils. Protein: Elevated. Glucose: Markedly low. Microscopy: AFB smear may show bacilli (negative does NOT exclude TBM). Culture: Should ALWAYS be done (takes up to 6 weeks). Brain imaging (CT/MRI): May show hydrocephalus, brisk meningeal enhancement, intracranial tuberculoma. Management: Start antituberculous chemotherapy AS SOON AS TBM is suspected (Do NOT wait for culture confirmation). Must include pyrazinamide. Glucocorticoids: Reduce mortality. Management of complications: Obstructive hydrocephalus $\rightarrow$ may require ventricular drainage. Skilled nursing care. Epilepsy Classification of Seizures A. Focal Seizures (= Focal onset; origin in one hemisphere) Focal onset – Awareness intact (= Former “simple partial”): Focal motor, focal sensory, non-motor (autonomic, emotional, sensory, experiential). Focal onset – Awareness impaired (= Former “complex partial”): Often temporal lobe. Automatisms: lip-smacking, picking, staring. Focal $\rightarrow$ Bilateral tonic–clonic (= Former “secondarily generalized”): Tonic, clonic, tonic–clonic. B. Generalized Seizures (Discharges begin simultaneously in both hemispheres) Generalized Motor Seizures: Tonic–clonic (Grand mal) Myoclonic group: Myoclonic, Myoclonic–atonic, Myoclonic–tonic, Myoclonic absence. Tonic Clonic Atonic ("Drop attacks") Epileptic spasms Generalized Non-Motor (Absence): Typical absence: Classic 3 Hz spike-and-wave. Atypical absence: Slow spike-and-wave; usually with structural brain disease. Absence with special features: Myoclonic absence, Eyelid myoclonia (Jeavons). C. Unknown Onset Seizures Used when onset cannot be determined. Epileptic spasms. Pathophysiology Epilepsy occurs due to an imbalance between neuronal excitation and inhibition. Intracellular recordings demonstrate a paroxysmal depolarisation shift (PDS), which is a sudden, prolonged depolarisation of the neuronal membrane that increases the likelihood of repetitive action potential firing. This results in bursts of hypersynchronous neuronal discharge. Clinical Features and Etiology A. Focal Onset Seizures Focal Aware Seizures (Simple Focal): Consciousness fully preserved. Motor: unilateral clonic jerks. Sensory: tingling, burning, electric sensations. Visual: coloured flashes, spots. Psychic: déjà vu, rising epigastric sensation. Autonomic: sweating, pallor. Patient remains aware. Jacksonian Seizure (Jacksonian March): Subtype of focal aware motor seizure. Begins with jerking in one small body area, “marches” sequentially along motor cortex. Followed by Todd’s paralysis. Focal Impaired Awareness Seizures (Temporal Lobe Epilepsy): Consciousness impaired. Patient stops, stares blankly. Automatisms: lip smacking, picking at clothes, chewing. Impaired memory, post-ictal confusion. Aura precedes: fear, déjà vu, nausea. Focal to Bilateral Tonic–Clonic Seizures: Often begins with aura. Evolves into tonic–clonic seizure. Post-ictal confusion and fatigue. B. Generalized Seizures Generalized Tonic–Clonic Seizures (GTC): Tonic phase (10–20 s): Loss of consciousness, ictal cry, cyanosis, apnea, jaw clenching, pupillary dilation. Clonic phase: Rhythmic jerking, autonomic storm. Post-ictal: Confusion, headache, amnesia, sore muscles. Absence Seizures (Typical): Start in childhood. Brief (seconds). Occur 20–30 times/day. Misinterpreted as daydreaming. Sudden behavioural arrest. No post-ictal confusion. Subtle automatisms. EEG: 3 Hz spike-and-wave. School performance decline. Investigations Detailed history and eyewitness account. Blood tests: metabolic derangements, secondary causes (electrolytes, glucose, calcium, infection markers). EEG: essential for detecting epileptiform activity (generalized spike-and-wave, focal spikes/sharp waves). MRI: detects structural causes of focal epilepsy (hippocampal sclerosis, cortical malformations, stroke, trauma, tumours, infections). Management Immediate care. Lifestyle advices: avoid triggers (sleep deprivation, alcohol withdrawal, missed doses, photic triggers). Counselling for stigma, work restrictions, driving regulations. Antiepileptic Drugs. Monitoring therapy. Epilepsy surgery: If two appropriate drugs fail $\rightarrow$ consider surgery, vagal nerve stimulation, deep brain stimulation. Neurostimulation: VNS, RNS, DBS (anterior thalamus). May withdraw after $>2$ years seizure-free, slowly over weeks–months. Status Epilepticus Seizure activity not resolving spontaneously, or recurrent seizure with no recovery of consciousness in between. Neurological emergency characterized by a seizure lasting $>5$ minutes, or recurrent seizures without recovery of consciousness between them. Two major types: A. Generalized Convulsive Status Epilepticus (GCSE): Persistent tonic–clonic movements. Coma + generalized electrographic seizure activity. B. Non-Convulsive Status Epilepticus (NCSE): Persistent absence or focal seizures. Altered consciousness, confusion. Minimal motor abnormalities. Often requires EEG for diagnosis. Etiology (Causes): Anticonvulsant withdrawal/noncompliance, metabolic disturbances, drug toxicity, CNS infection, neoplasia, stroke, refractory epilepsy, head trauma. Treatment: Emergent Stabilization (0–5 min): Airway, breathing, circulation. Oxygen, suction, recovery position. Check blood glucose, give IV dextrose if low. Establish IV access. Draw labs. Control hyperthermia. Jacksonian Epilepsy Focal motor seizure beginning in one small body part (e.g., fingers or face) with orderly, sequential spread (“Jacksonian march”) reflecting propagation of epileptic discharge across the motor cortex. Awareness is preserved initially. Focal seizures can spread to produce secondary generalized tonic–clonic seizures. Post-ictally, Todd’s paralysis may occur. Causes include focal cortical lesions—tumors, stroke, trauma, infections, cortical dysgenesis. Diagnosis is by focal discharges on ictal EEG and MRI for structural causes. Management follows focal epilepsy guidelines: lamotrigine or carbamazepine as first-line drugs, with alternatives such as levetiracetam. Drug-resistant cases may benefit from surgical resection or VNS/DBS. Todd’s Paralysis Transient focal neurological deficit occurring after focal motor seizures, especially Jacksonian epilepsy. Localized paresis for minutes to many hours following the seizure. Results from temporary post-ictal neuronal exhaustion after paroxysmal depolarisation. Weakness begins immediately after the seizure, corresponds to the body part involved, and fully resolves. Investigation is aimed at excluding stroke, using EEG and MRI. Management is supportive, with no specific therapy needed. Stroke A stroke, or cerebrovascular accident, is: “an abrupt onset of a neurologic deficit that is attributable to a vascular cause.” It is a clinical diagnosis. Symptoms occur because cerebral blood flow decreases long enough to cause brain infarction. If neurologic deficits last $>24$ hours or imaging shows infarction $\rightarrow$ stroke. I. Ischemic Stroke ($\sim85\%$): Large-artery atherosclerotic, Cardioembolic, Small-vessel (lacunar), Other determined causes, Cryptogenic. II. Hemorrhagic Stroke ($\sim15\%$): Intracerebral hemorrhage (hypertensive, CAA, anticoagulant-related, vascular malformations, tumor bleed), Subarachnoid hemorrhage (aneurysmal, traumatic, AVM), Intraventricular hemorrhage. I. Ischemic Stroke – Pathogenesis Arterial occlusion: Thrombus or embolus blocks cerebral artery. CBF decreases immediately. Formation of ischemic core: CBF $ Formation of ischemic penumbra: CBF 10–20 mL/100 g/min. Neurons are functionally silent but viable. Tissue salvageable $\rightarrow$ target of therapy. Energy failure: Lack of oxygen + glucose $\rightarrow \downarrow$ATP. Na$^+$/K$^+$ pump fails $\rightarrow$ membrane depolarization. Glutamate excitotoxicity: Excess glutamate released. NMDA/AMPA receptor activation $\rightarrow$ Ca$^{2+}$ overload. Intracellular Ca$^{2+}$ overload: Leads to activation of proteases, lipases, endonucleases, nitric oxide synthase $\rightarrow$ structural destruction. Free radical (ROS) production: From mitochondria + reperfusion. Causes lipid peroxidation + DNA damage. Inflammatory cascade: Microglial activation. Leukocyte recruitment. Cytokine release $\rightarrow$ secondary neuronal death. Spreading depolarizations: Propagating waves spreading from core. Worsen penumbral injury. Expand infarct territory. Outcome: Core: necrosis. Penumbra: apoptosis + inflammatory injury. Delay worsens infarct $\rightarrow$ "Time is Brain." II. Intracerebral Haemorrhage (ICH) – Pathogenesis Vessel rupture: Most commonly hypertensive small vessels. Bleeding occurs into deep brain structures. Hematoma forms: Blood rapidly accumulates in the parenchyma. Hematoma expansion: Occurs over 1–3 hours. Major cause of early neurological deterioration. Increased intracranial pressure: Hematoma exerts mass effect. Causes midline shift, herniation risk. Perihematomal injury: Surrounding brain is compressed, not infarcted. Toxic effects of blood breakdown products: Hemoglobin, iron, thrombin $\rightarrow$ oxidative injury. BBB disruption $\rightarrow$ edema. Inflammatory response: Microglial activation. Pro-inflammatory cytokines. ROS generation. Edema formation: Develops over several days. Major cause of late deterioration. Risk Factors Category Ischemic Stroke Risk Factors Hemorrhagic Stroke Risk Factors NON-MODIFIABLE Increasing age, Male sex, Family history of stroke, Prior stroke/TIA, Genetic disorders Age (esp. $>70$ yrs), Male sex, Cerebral amyloid angiopathy (CAA), Genetic vasculopathies MAJOR MODIFIABLE Hypertension (most important), Diabetes mellitus, Dyslipidemia, Smoking, Obesity, Physical inactivity, Unhealthy diet, Alcohol excess Hypertension (most important), Alcohol binge drinking, Smoking, Poorly controlled diabetes CARDIOVASCULAR Atrial fibrillation (major cause), Recent MI (LV thrombus), Cardiomyopathy, Valvular disease, Patent foramen ovale (PFO), Infective endocarditis Anticoagulant-associated bleeding, Prosthetic valves, INR elevation from warfarin/DOACs CEREBROVASCULAR / ARTERIAL Carotid atherosclerosis, Intracranial atherosclerosis, Small-vessel disease, Arterial dissection, Vasculitis, Moyamoya disease Ruptured aneurysms, Arteriovenous malformations (AVM), Cavernous malformations, Cerebral amyloid angiopathy (CAA) HEMATOLOGIC / HYPERCOAGULABLE Antiphospholipid syndrome, Protein C/S deficiency, Factor V Leiden, Prothrombin mutation, Malignancy, Pregnancy/OCP Coagulopathy (thrombocytopenia, DIC), Liver disease, Over-anticoagulation LIFESTYLE / DRUGS Smoking, Heavy alcohol consumption, Physical inactivity, High stress Cocaine use, Amphetamines, Heavy alcohol binge, Smoking OTHER CONDITIONS Chronic kidney disease, Sleep apnea, Hyperhomocysteinemia, Elevated CRP Tumors with bleeding tendency, Trauma Clinical Features Overall Onset: Sudden onset of focal neurological deficit; embolic = abrupt & maximal, thrombotic = stuttering/stepwise. Symptoms: Depend on territory (motor, sensory, visual, language, brainstem, cerebellar signs). Consciousness: Usually preserved in ischemia unless massive infarct; often impaired early in ICH/SAH. Associated symptoms: Headache, vomiting, seizures (more common in hemorrhagic strokes). Ischemic Stroke – Clinical Features Typical Onset: Sudden onset neurological deficit; embolic = “instant maximal”; thrombotic = fluctuating, stepwise. General Symptoms: Hemiparesis, hemisensory loss, aphasia, dysarthria, visual field deficits, vertigo, ataxia, facial droop. Consciousness: Usually normal; decreased only in large infarcts, basilar artery occlusion, or malignant MCA infarct. Headache: Less common than hemorrhagic. Seizures: Less common; may occur in cortical infarcts. Progression: Neurological deficit may worsen due to edema (peak 2–3 days). Based on Location Artery / Territory Clinical Features (Detailed) MCA – Middle Cerebral Artery Contralateral face $>$ arm $>$ leg weakness, contralateral hemisensory loss, aphasia (if dominant), neglect (if nondominant), homonymous hemianopia, gaze deviation toward lesion ACA – Anterior Cerebral Artery Contralateral leg $>$ arm weakness, abulia, apathy, urinary incontinence, primitive reflexes, personality change PCA – Posterior Cerebral Artery Contralateral homonymous hemianopia, visual agnosia, alexia without agraphia, thalamic pain syndrome Basilar Artery Quadriplegia, “Locked-in syndrome,” coma Vertebral Artery Vertigo, vomiting, nystagmus, ipsilateral facial loss + contralateral body loss (Wallenberg) Cerebellar Arteries Severe vertigo, ataxia, nausea, vomiting, dysmetria, risk of rapid edema $\rightarrow$ brainstem compression Hemorrhagic Stroke – Clinical Features Onset: Sudden; often during activity or acute rise in BP. Headache: Very common and often severe. Vomiting: Common at onset. Consciousness: Early impairment, depending on hematoma size & location. Seizures: More common than ischemic stroke (lobar ICH). Progression: Rapid deterioration due to hematoma expansion in first 3 hours, then progressive edema over days. Type / Location Clinical Features (Detailed) Deep ICH (basal ganglia, thalamus) Contralateral hemiparesis, hemisensory loss, gaze deviation, early altered consciousness Lobar Hemorrhage (CAA) Seizures, cortical deficits: aphasia, neglect, visual loss Pontine Hemorrhage Sudden coma, quadriplegia, pinpoint pupils, decerebrate posturing Cerebellar Hemorrhage Sudden vertigo, vomiting, ataxia, nystagmus, rapid brainstem compression $\rightarrow$ coma Thalamic Hemorrhage Sensory loss, gaze palsies, confusion/coma Ventricular Extension Acute hydrocephalus, reduced consciousness, severe headache Diagnosis Initial Assessment & Confirmation of Stroke History & onset: Determine time last seen normal, abrupt vs stuttering onset, risk factors, medications. Clinical exam: Focal deficits. Exclude mimics: Hypoglycemia, seizures, migraine, encephalopathy. Imaging – Cornerstone of Diagnosis Imaging Purpose Findings / Notes Non-contrast CT (NCT) – FIRST TEST Immediately distinguish ischemic vs hemorrhagic stroke. Detects acute ICH within minutes. Early ischemia may appear normal. CT Angiography (CTA) Detects large-vessel occlusion. Used for thrombectomy planning; shows absent vessel flow. CT Perfusion (CTP) Defines core infarct vs penumbra $\rightarrow$ guides reperfusion. Shows mismatch volumes; identifies salvageable tissue. MRI with DWI Most sensitive early ischemia detector (within minutes). Detects posterior fossa strokes and small infarcts better than CT. MR Angiography (MRA) Evaluates intracranial/extracranial vascular disease. Detects dissections, stenosis, aneurysms. DSA (Digital Subtraction Angiography) Gold standard for aneurysm/AVM detection. Used when small-vessel detail needed or intervention planned. Special Imaging for Hemorrhagic Stroke Test Purpose Key Findings CT head Identifies ICH and location. Hyperdense hematoma, mass effect. CTA for Spot Sign Predicts hematoma expansion. Contrast “spot sign” = active bleeding. MRI (GRE/SWI) Detect microbleeds, chronic hemorrhage. Useful for posterior fossa hemorrhage. 3. Laboratory Investigations Help identify mimics, risk factors, and eligibility for thrombolysis. Key tests: Glucose, CBC, Electrolytes, Coagulation profile (INR/PT/APTT), Renal & liver function tests, Cardiac enzymes if MI suspected, Toxicology screen. For long-term prevention: Lipid profile, HbA1c, ESR/CRP if vasculitis suspected. 4. Cardiac Evaluation (For Embolic Stroke) A. ECG: Detects Atrial fibrillation, Recent MI, Conduction abnormalities. B. Telemetry / Holter Monitoring: Identifies paroxysmal AF. C. Echocardiography: TTE (chamber size, EF, LV thrombus), TEE (valvular disease, aortic arch plaque, PFO, atrial thrombi). 5. Vascular Studies A. Carotid Doppler Ultrasound: Checks Carotid stenosis, Plaque morphology, Blood flow velocity. B. CTA / MRA Neck: Useful for Carotid/vertebral dissection, Intracranial stenosis, Complete occlusions. 6. Special Diagnostics for Hemorrhagic Strokes A. Intracerebral Hemorrhage (ICH): CT identifies hematoma size, location, mass effect. CTA spot sign predicts active bleeding. MRI (GRE/SWI) detects old microbleeds. B. Subarachnoid Hemorrhage (SAH): CT detects subarachnoid blood. If CT negative but high suspicion $\rightarrow$ Lumbar puncture for xanthochromia. CTA/MRA identifies aneurysm. Acute Ischemic Stroke — Management Management involves: Immediate stabilization, Rapid neuroimaging, Reperfusion therapy, Prevention of complications, Secondary prevention. 1. Pre-Hospital Care & Early Stabilization A. FAST Recognition: Face droop, Arm weakness, Speech difficulty, Time to call emergency. B. Airway, Breathing, Circulation (ABC): Ensure airway patency. Oxygen ONLY if SpO$_2 C. Positioning: Head end elevated $30^\circ$. D. Check Blood Glucose: Correct immediately if $ E. Immediate IV Access: Isotonic saline. 2. Emergency Room Acute Assessment A. Determine Time of Onset: Most important step $\rightarrow$ eligibility for IV thrombolysis ($\le4.5$ hours), Mechanical thrombectomy ($\le6-24$ hours). B. Perform NIHSS Score: Assesses stroke severity. C. Rule Out Stroke Mimics: Hypoglycemia, Post-ictal paralysis, Migraine, Infection, Tumor, Metabolic derangements. 3. Urgent Neuroimaging A. Non-Contrast CT (FIRST): Rule out intracerebral hemorrhage. Done within 20 minutes of arrival. B. CT Angiography (CTA): Detect large-vessel occlusions. Required for thrombectomy planning. C. CT Perfusion (CTP): Identify penumbra vs core. Mandatory in extended-window (6–24 hr) thrombectomy. D. MRI Brain with DWI: More sensitive early. Best for posterior fossa stroke. 4. Reperfusion Therapy A. Intravenous Thrombolysis — Alteplase (tPA): Time window: $\le4.5$ hours. Dose: 0.9 mg/kg (max 90 mg). 10% as bolus, 90% over 1 hour. Inclusion Criteria: Clinical diagnosis of ischemic stroke, Onset $ Must Control BP Before tPA: BP must be $ Contraindications (Major): ICH on CT, Recent surgery/trauma, INR $>1.7$, platelets $ 185/110$ unresponsive, Previous ICH, Active bleeding. B. Mechanical Thrombectomy: Indicated for: Large vessel occlusion (ICA, M1/M2, basilar), NIHSS $\ge6$, ASPECTS $\ge6$. Time: 0–6 hours (standard), 6–24 hours if perfusion mismatch. 5. Antithrombotic Management A. Antiplatelet Therapy: If NO tPA: give Aspirin 160–325 mg immediately. If tPA GIVEN: start after 24 hrs post-repeat CT. Dual antiplatelets (Aspirin + Clopidogrel) for 21 days in minor stroke, high-risk TIA. B. Anticoagulation: Not given acutely. For atrial fibrillation–related stroke: Start oral anticoagulation (DOACs or Warfarin). 6. Management of Cerebral Edema & Complications. 7. Secondary Prevention of Ischemic Stroke A. Antiplatelets: Aspirin, Clopidogrel, Aspirin + Dipyridamole. B. Anticoagulation for AF: DOACs preferred. C. Statins: High-intensity therapy (Atorvastatin 40–80 mg). Aim LDL $ D. Blood Pressure Control: Target $ E. Diabetes Management: HbA1c $ F. Lifestyle Modification: Stop smoking, weight loss, exercise, reduce alcohol, Mediterranean/DASH diet. G. Carotid Revascularization: For symptomatic 70–99% stenosis (CEA best). Management of Hemorrhagic Stroke A. Intracerebral Hemorrhage (ICH) Management ICH is a medical and neurosurgical emergency. Mortality is high, and early management focuses on preventing hematoma expansion, reducing intracranial pressure, correcting coagulopathies, and treating life-threatening complications. 1. Immediate Priorities: Stabilize Airway, Breathing, Circulation. Intubate if GCS $ 94\%$. Maintain adequate perfusion pressure. 2. Blood Pressure Control (KEY INTERVENTION): Targets: If SBP 150–220 mmHg $\rightarrow$ Lower rapidly to $\sim140$ mmHg. Avoid SBP $ Use IV agents: Nicardipine, Labetalol, Clevidipine. 3. Reversal of Anticoagulation: A. Warfarin-induced bleeding: 4-factor PCC (first line), IV Vitamin K. B. Dabigatran: Idarucizumab. C. Factor Xa inhibitors (Apixaban, Rivaroxaban): Andexanet alfa. D. Antiplatelet reversal: Consider desmopressin (DDAVP). 4. Control of Intracranial Pressure (ICP): A. Positioning: Head elevation $30^\circ$. B. Osmotic Therapy: Mannitol, Hypertonic saline. C. Ventricular Drainage: External Ventricular Drain (EVD). D. Sedation: Propofol. E. Avoid: Hypotonic fluids, Steroids. 5. Prevention of Hematoma Expansion: Rapid BP control, Reversal of anticoagulation, Avoid antiplatelets/anticoagulants/NSAIDs. Maintain normothermia/euglycemia. rFVIIa reduces expansion but not outcomes. 7. Metabolic & General Care: Temperature control, Glucose management, Seizure management, DVT prophylaxis, Nutrition & aspiration prevention. 8. Long-Term Management After ICH: Aggressive BP control lifelong. Avoid anticoagulation. Manage underlying cause. Rehab. B. Subarachnoid Hemorrhage (SAH) Management SAH is most commonly due to ruptured berry aneurysm. It has two main threats: 1. Rebleeding, 2. Delayed cerebral ischemia (vasospasm). Management is more protocolized and time-critical. 1. Immediate Management: A. Stabilization: Secure airway. BP control (target SBP $ B. Prevent Rebleeding (Highest priority): Definitive aneurysm treatment within 24–72 hours (Endovascular coiling preferred or Surgical clipping). 2. Prevention of Delayed Cerebral Ischemia (Vasospasm): NIMODIPINE – Only proven therapy (60 mg orally every 4 hours for 21 days). Monitoring for Vasospasm: Daily Transcranial Doppler (TCD). Clinical monitoring. If symptomatic vasospasm occurs: Maintain euvolemia, Induce hypertension, Endovascular (balloon angioplasty, intra-arterial vasodilators). 3. Management of Hydrocephalus: External Ventricular Drain (EVD). 4. Other Supportive Care: Seizure Management, Electrolyte Management (hyponatremia), Temperature Control, DVT Prevention, Ventilation and ICP, Nutrition. 5. Long-Term Management After SAH: Regular BP control. Avoid smoking, alcohol. Treat aneurysms in other sites. Cognitive and physical rehabilitation. Monitor for long-term complications (epilepsy, hydrocephalus). TIA (Transient Ischemic Attack) TIA is a brief episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia without acute infarction. It is a sudden, focal neurological deficit lasting less than 24 hours, usually resolving within minutes to 1 hour, and caused by temporary cerebral ischemia without permanent damage. Pathogenesis: TIA occurs due to transient focal ischemia from embolic, thrombotic, or low-flow mechanisms. Blood flow falls enough to cause neuronal dysfunction but is restored before irreversible neuronal injury. Infarction is absent on DWI MRI. Etiology: Same causes as ischemic stroke (emboli, large artery atherosclerosis, small-vessel disease, hemodynamic hypotension + carotid stenosis, dissection, hypercoagulable states, vasculitis, genetic vasculopathies). Symptoms: Depend on the vascular territory. Carotid TIA causes hemiparesis, hemisensory loss, aphasia, and amaurosis fugax. Vertebrobasilar TIA causes vertigo, diplopia, ataxia, dysarthria, and bilateral symptoms. Lacunar TIAs produce pure motor or pure sensory episodes. Neurological function returns completely after each episode. TIA Management Step Treatment Details Immediate antiplatelet Aspirin 160–325 mg First-line if no contraindication DAPT Aspirin + Clopidogrel 21 days in high-risk TIA/minor stroke Statins Atorvastatin 40–80 mg LDL $ Anticoagulation (if AF) DOACs or Warfarin Start once hemorrhage excluded Carotid intervention CEA (best) or CAS For symptomatic 70–99% stenosis; within 2 weeks BP control Target $ ACEI/ARB + thiazide $\pm$ CCB Diabetes control HbA1c $ SGLT2 inhibitors / metformin Lifestyle Stop smoking, exercise, diet Mediterranean/DASH diet Hospital admission ABCD2 $\ge4$ or unstable symptoms Crescendo TIAs = emergency Long-term prevention Single antiplatelet + statin Lifelong risk-factor control Guillain-Barré Syndrome (GBS) / Post-Infective Polyneuropathy / Acute Inflammatory Polyneuropathy / Acute Inflammatory Demyelinating Polyneuropathy (AIDP) A rapidly evolving, acute, frequently severe, immune-mediated polyradiculoneuropathy, characterized by areflexic weakness, usually beginning in the legs and ascending over hours to days, often following an infection and resulting from autoimmune attack on peripheral nerves or roots. Etiology / Precipitating Factors: Commonly post-infectious (1–4 weeks after): A. Infective Triggers: Campylobacter jejuni (strongest association), Cytomegalovirus, Epstein–Barr virus, Mycoplasma pneumoniae, Influenza, Zika virus, HIV seroconversion. B. Non-Infective Triggers: Recent vaccination (rare), Surgery, Trauma, Immune checkpoint inhibitors, Lymphoma or systemic immune activation. Pathogenesis: Autoimmune attack on the peripheral nervous system induced by molecular mimicry after infection. AIDP (Most common) — Demyelinating GBS: Autoreactive T cells and antibodies target Schwann-cell myelin. Complement deposition $\rightarrow$ segmental demyelination, conduction block. Macrophage-mediated stripping of myelin. Axonal GBS (AMAN/AMSAN): Antibodies (IgG) target gangliosides GM1, GD1a at nodes of Ranvier. Complement-mediated nodal disruption $\rightarrow$ primary axonal degeneration. Clinical Features: A. Motor Symptoms (Most prominent): Rapidly progressive, ascending symmetrical weakness: legs $\rightarrow$ arms $\rightarrow$ face $\rightarrow$ bulbar $\rightarrow$ respiratory muscles. Peaks within 2 weeks. Facial weakness in 50%. B. Reflexes: Generalized areflexia or hyporeflexia (hallmark). C. Sensory Symptoms: Distal paresthesias, mild sensory loss, deep aching pain. D. Cranial Nerve Involvement: Facial diplegia, bulbar palsy (dysphagia, nasal speech), ophthalmoplegia (Miller Fisher variant). E. Autonomic Dysfunction: Fluctuating BP, Tachycardia/bradycardia, Arrhythmias, Urinary retention, Ileus, constipation, sweating abnormalities. F. Respiratory Failure: Seen in $\sim30\%$. Reduced vital capacity $\rightarrow$ requires ventilation. G. Variants: AIDP, AMAN/AMSAN, Miller Fisher Syndrome (ophthalmoplegia + ataxia + areflexia), Pharyngeal–cervical–brachial variant. Management Two major pillars: Supportive & Intensive care (most important) and Immunotherapy (IVIg or Plasma Exchange). Supportive / ICU Management (Lifesaving Component) A. Respiratory Monitoring & Ventilatory Support: Early respiratory failure common. VC $ B. Autonomic Dysfunction Management (critical): Continuous cardiac monitoring. Avoid drugs that suppress heart rate. Treat hypertension with short-acting agents. Hypotension: fluids, vasopressors. Arrhythmias: may need pacemaker. C. Prevention of Complications: DVT/PE (LMWH, stockings), Pressure Ulcers, Aspiration Prevention (NG tube feeding), Pain Management (NSAIDs, gabapentin), Bladder/GI Care, Nutrition Support, Eye Care. Specific Immunotherapy (Disease-Modifying Treatment) A. Intravenous Immunoglobulin (IVIg): Dose: 0.4 g/kg/day $\times 5$ days (total 2 g/kg). Advantages: Easy to administer, works well in children/unstable patients, better for autonomic dysfunction. Indications: Unable to walk independently, rapid progression, respiratory/bulbar involvement, autonomic dysfunction, within first 2 weeks. B. Plasma Exchange (PLEX / Plasmapheresis): Course: 4–6 exchanges over 7–10 days. Mechanism: Removes circulating antibodies, complement, immune complexes. Benefits: Equivalent efficacy to IVIg, faster improvement in severe cases. Indications: Same as IVIg. Contraindications: Severe hemodynamic instability, sepsis, lack of vascular access. Give EITHER ONE only. Treatments Not Recommended: Corticosteroids, Interferons, cyclophosphamide, rituximab. Complications Respiratory failure, Aspiration pneumonia, Arrhythmias, BP lability, DVT/PE, Pressure sores, Neuropathic pain, Sepsis. Differential Diagnosis Condition How it Mimics GBS How to Distinguish From GBS Acute Transverse Myelitis Weakness $\pm$ sensory level UMN signs, hyperreflexia, Babinski; bladder early; MRI spine abnormal Poliomyelitis / Acute Flaccid Myelitis Acute flaccid paralysis Asymmetric; fever; CSF pleocytosis; viral PCR positive Myasthenia Gravis Bulbar weakness, respiratory failure Normal reflexes; fluctuating weakness; positive AChR antibodies Botulism Cranial palsy, autonomic signs Descending paralysis, dilated pupils, normal sensation Tick Paralysis Acute ascending paralysis No sensory loss; rapid reversal after tick removal Porphyria (AIP) Motor neuropathy Severe abdominal pain, psychiatric signs, dark urine; porphyrin $\uparrow$ Critical illness neuropathy Weakness in ICU Occurs in sepsis or multi-organ failure; NCS different Toxic Neuropathy Motor-sensory deficits Exposure history, GI symptoms, anemia Diphtheritic polyneuropathy Neuropathy following infection Follows pharyngitis; slow progression; cranial nerves early Peripheral Neuropathy Disorders of peripheral nerves involving motor, sensory, or autonomic fibers individually or in combination. Damage may occur at: Neuron cell body (neuronopathy/ganglionopathy), Axon (axonopathy), Myelin sheath (myelinopathy/demyelinating neuropathy). Classification Based on Pattern: Mononeuropathy: Entrapment (carpal tunnel), ulnar neuropathy. Mononeuritis multiplex: Vasculitis, diabetes, amyloidosis. Symmetrical polyneuropathy: Diabetes, toxic, nutritional, hereditary. Radiculopathy: Disc prolapse, compression. Plexopathy: Trauma, radiation, diabetes. Clinical Features: Depend on fiber type involved. A. Sensory Symptoms: Numbness, tingling, burning, lancinating pain (small fiber), loss of vibration/proprioception $\rightarrow$ sensory ataxia. B. Motor Symptoms: Distal $>$ proximal weakness, foot drop, muscle wasting, reduced/absent reflexes. C. Autonomic Symptoms: Postural hypotension, bladder dysfunction, erectile dysfunction, abnormal sweating. Diagnostic Approach: History, exam, electrodiagnostic studies, targeted tests. A. Nerve Conduction Studies / EMG: Axonal neuropathy: $\downarrow$ CMAP/SNAP amplitudes, Preserved conduction velocities, Fibrillations on EMG. Demyelinating neuropathy: Slowed conduction velocities, Prolonged distal latency, Conduction block, Temporal dispersion. B. Autonomic Testing: Heart rate variability, BP response to tilt table, QSART. C. Laboratory Tests: Blood sugar/HbA1c, B12, vitamin E, thyroid profile, ANA, ANCA, Serum electrophoresis. D. Nerve Biopsy: Indicated mainly for vasculitis, amyloidosis. E. Skin Biopsy: For small fiber neuropathy. Management: Focuses on correcting underlying causes, controlling neuropathic pain, and supportive rehabilitation. Cerebellar Ataxia Impaired coordination of voluntary movements due to dysfunction of the cerebellum or its afferent/efferent pathways. Causes disturbances of gait, balance, limb coordination, speech (scanning dysarthria), eye movements. Clinical Features: A. Gait & Posture Abnormalities: Wide-based, unsteady gait. Veering to affected side. Difficulty with tandem walking. Positive Romberg only if sensory loss coexists. B. Limb Incoordination: Dysmetria (overshooting/undershooting), Dysdiadochokinesia (impaired rapid alternating movements), Intention tremor. C. Eye Movement Abnormalities: Nystagmus (horizontal, vertical, gaze-evoked), Saccadic intrusions, Impaired smooth pursuit. D. Speech Disturbances: Scanning dysarthria (irregular rhythm), slurred, slow, explosive speech. E. Hypotonia: Reduced muscle tone, Pendular knee jerks. F. Cognitive/Affective Changes: Executive dysfunction, Spatial disorganization, Emotional blunting or disinhibition. Acute Onset Paraplegia Sudden weakness or paralysis of both lower limbs developing over minutes to hours (hyperacute) or hours to days (acute) due to lesion affecting the thoracic spinal cord or its pathways. Neurological emergency. Anatomical Basis: Lesions at any level from T1 to conus medullaris, or affecting LMN structures. UMN pattern $\rightarrow$ spinal cord lesions. LMN pattern $\rightarrow$ GBS, radiculopathy, metabolic causes. Causes: A. Spinal Cord Compression (NEUROLOGY EMERGENCY): Epidural abscess, Epidural hematoma, Vertebral fractures/trauma, Tumor compression, Tuberculosis spine (Pott’s disease). B. Non-compressive Spinal Cord Lesions: Acute Transverse Myelitis, Multiple sclerosis relapse, Neuromyelitis optica (AQP4)/MOGAD, Post-infectious or post-vaccination myelitis, Radiation myelopathy. C. Vascular Causes: Anterior spinal artery infarction, Aortic dissection, Post-aortic aneurysm surgery, Hypotensive spinal watershed infarction. D. Peripheral Nerve Disorders (LMN Paraplegia): Guillain–Barré syndrome (GBS), AMAN/AMSAN variants, Acute motor neuropathies. E. Metabolic & Toxic Causes: Hypokalemic periodic paralysis, Hyperkalemia, Hypophosphatemia, Hypomagnesemia, Thyrotoxic periodic paralysis, Organophosphate poisoning. F. Muscle Disorders (Acute Myopathy): Polymyositis/dermatomyositis, Rhabdomyolysis, Critical illness myopathy, Statin-induced myopathy. G. Functional (Psychogenic) Paralysis. Clinical Features: A. Symptoms: Sudden inability to walk/stand, Bilateral leg weakness, Tingling, numbness, Back pain, Bladder retention/incontinence, Saddle anesthesia. B. Signs: 1. UMN Paraplegia (Spinal cord lesion): Spasticity, Hyperreflexia, Positive Babinski, Sensory level present. 2. LMN Paraplegia (GBS, metabolic): Flaccid paralysis, Areflexia, No sensory level, Autonomic disturbance. 3. Spinal Shock (Early phase of cord injury): Flaccid limbs, Areflexia, No plantar response. Red Flag Features (Require IMMEDIATE MRI): Severe back pain, Rapid progression, Bladder/bowel involvement, Saddle anesthesia, Fever + back pain, Anticoagulation history, Trauma history, Suspicion of vascular catastrophe. Diagnostic Approach: A. Immediate Tests: MRI spine with contrast (first-line). If MRI unavailable $\rightarrow$ CT myelography. Serum electrolytes, Glucose, renal and liver function. B. If MRI Normal $\rightarrow$ Think LMN Causes: Nerve conduction study (NCS)/EMG. CSF examination. C. Autoimmune & Infectious Tests: ANA, anti-AQP4, anti-MOG, Viral serology, ESR/CRP, Thyroid function tests. D. Vascular Tests: CTA/MRA aorta, Coagulation profile. Management: Depends on cause; early intervention prevents permanent deficits. A. Spinal Cord Compression $\rightarrow$ URGENT: Epidural Abscess (IV antibiotics, Surgical decompression), Epidural Hematoma (Stop anticoagulants, Emergency decompression), Tumor compression (High-dose IV dexamethasone, Urgent surgery or radiotherapy). B. Non-compressive Myelopathies: Acute Transverse Myelitis (IV methylprednisolone, Plasma exchange), NMOSD/MOGAD (High-dose steroids, Plasma exchange). C. Vascular Myelopathy: Maintain blood pressure, Antiplatelets/anticoagulation, Manage aortic dissection. D. Peripheral Causes: Guillain–Barré Syndrome (IVIg OR Plasmapheresis). E. Metabolic Causes: Hypokalemic Paralysis (IV potassium chloride), Other electrolyte abnormalities (correct Mg$^{2+}$, PO$_4$, Ca$^{2+}$). F. Myopathic Causes: Treat underlying cause (Steroids/immunotherapy for polymyositis, Hydration + alkalinization for rhabdomyolysis). G. Functional Paralysis: Reassurance, Psychological therapy, Physiotherapy. Rehabilitation: Physiotherapy, Prevention of contractures, Bladder/bowel training, DVT prophylaxis, Pressure sore prevention, Gait training. Lumbar Puncture A sterile medical procedure performed by inserting a spinal needle between the L3–L4 or L4–L5 interspaces into the lumbar subarachnoid space to: Collect CSF, Measure opening pressure, Administer medications, Diagnose CNS infections, inflammatory/neoplastic diseases, and subarachnoid hemorrhage. The procedure accesses the CSF space below the termination of the spinal cord (conus medullaris), making it safe. Landmark: Tuffier’s line = line connecting iliac crests $\rightarrow$ L4 spinous process. Indications: Diagnostic: Meningitis (bacterial, viral, TB, fungal), Encephalitis, Subarachnoid hemorrhage, Multiple sclerosis, Guillain–Barré syndrome, Carcinomatous meningitis, Neurosyphilis, CJD, Autoimmune CNS diseases, Hydrocephalus evaluation, Metabolic/Genetic diseases. Therapeutic: Idiopathic intracranial hypertension, Normal-pressure hydrocephalus (diagnostic tap test), Intrathecal administration of drugs (chemotherapy, antibiotics, antivirals), Spinal anesthesia. Contraindications: Absolute: Signs of raised ICP due to mass effect (papilledema, focal deficits, altered consciousness), Coagulopathy, Local infection at puncture site, Spinal cord compression. Relative: Severe spinal deformity, Suspected epidural abscess, Hemodynamic instability, Uncooperative patient. The Procedure: A. Positioning: Lateral decubitus (preferred). Flex spine maximally. B. Equipment: Spinal needle (20G–22G, Quincke or Whitacre), Manometer, Sterile drapes, Local anesthetic, Tubes (4 tubes standard). C. Technique: Clean area, Identify L3–L4/L4–L5, Local anesthesia, Insert needle midline (bevel parallel to dural fibers), Feel first pop (ligamentum flavum), Advance millimeters $\rightarrow$ second pop (dura), Withdraw stylet $\rightarrow$ CSF flows, Attach manometer $\rightarrow$ measure opening pressure, Collect CSF in 4 tubes, Replace stylet $\rightarrow$ withdraw needle, Seal. Complications: A. Common: Post-LP headache, Back pain, Bloody tap. B. Serious: Brain herniation (MOST DANGEROUS), Spinal Epidural Hematoma, Infection (Epidural abscess, Meningitis), Subdural hygroma and hematoma. CSF Normal Values Parameter Normal Value Opening pressure 10–20 cm H$_2$O Appearance Clear, colorless Cells 0–5 lymphocytes/$\mu$L Protein 15–45 mg/dL Glucose 45–80 mg/dL (2/3 of blood glucose) Chloride 118–132 mEq/L Abnormal CSF Condition Opening Pressure Cells Protein Glucose Special Findings Normal 10–20 cm H$_2$O 0–5 lymphocytes 15–45 mg/dL 2/3 serum glucose – Bacterial meningitis $\uparrow\uparrow$ $\uparrow\uparrow$ PMNs $\uparrow\uparrow$ $\downarrow ( Gram stain+, culture+ Viral meningitis Often normal/$\uparrow$ $\uparrow$ lymphocytes Mild $\uparrow$ Normal PCR for HSV/enterovirus TB meningitis $\uparrow$ $\uparrow$ lymphocytes $\uparrow\uparrow$ $\downarrow$ Cobweb clot, ADA$\uparrow$ Fungal meningitis $\uparrow$ $\uparrow$ lymphocytes $\uparrow$ $\downarrow$ India ink+, cryptococcal antigen Subarachnoid hemorrhage $\uparrow$ RBCs in all tubes Mild $\uparrow$ Normal Xanthochromia GBS (AIDP) Normal Normal $\uparrow\uparrow$ (“albuminocytologic dissociation”) Normal Protein $>100$ after 1 week Multiple sclerosis Normal Mild lymphocytes Normal/mild $\uparrow$ Normal Oligoclonal bands Xanthochromia in CSF Yellow discoloration of the cerebrospinal fluid (CSF). Occurs due to bilirubin formation from breakdown of red blood cells in the subarachnoid space after hemorrhage. LP should be performed 12 hours after symptom onset to allow detection of xanthochromia. Helps confirm subarachnoid hemorrhage when CT is negative. Always pathological. Seen in: SAH, Jaundice, Excess protein in CSF, Carotene excess, Froin’s syndrome. Myasthenia Gravis Autoimmune disorder of the neuromuscular junction characterized by weakness and fatigability of skeletal muscles due to autoantibodies targeting postsynaptic acetylcholine receptors (AChRs) or associated proteins such as MuSK. Presents 15–50 yrs, female preponderance in younger; males more common in older. Etiology: Autoimmune, antibody mediated. Anti-AChR antibodies ($80\%$ cases), Anti-MuSK antibodies, Anti-LRP4, anti-agrin. MG causes decrease in functional AChRs + structural damage leading to failed neuromuscular transmission. Clinical Features: Weakness Pattern: Fatigable weakness (worsens with activity, improves with rest). No sensory loss. Ocular Symptoms (first in 60–70%): Ptosis, Diplopia (Cogan lid twitch sign). Bulbar Manifestations: Dysarthria, Nasal speech, Dysphagia, Fatigue while chewing. Limb Weakness: Proximal $>$ distal. Shoulder girdle common. Respiratory Weakness: May lead to myasthenic crisis. Ventilatory failure possible. Course: Relapsing–remitting. Fluctuating weakness throughout day. Management: A. Symptomatic Therapy: Pyridostigmine (first-line). B. Immunotherapy: Short-term: IVIg, Plasma exchange (PLEX) for MG crisis, pre-thymectomy, severe weakness. Intermediate-term: Glucocorticoids (prednisone), Cyclosporine/Tacrolimus, Rituximab. Long-term: Azathioprine, Mycophenolate mofetil. C. Thymectomy: Indications: Thymoma (always), Non-thymomatous generalized AChR-positive MG.