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CRANIAL NERVE LONG CASE - COMPLETE GUIDE

Mnemonics for the 12 cranial nerves: "Oh Oh Oh, To Touch And Feel Very Good Velvet, Ah Heaven" CN I-II-III-IV-V-VI-VII-VIII-IX-X-XI-XII Sensory/Motor/Both: "Some Say Marry Money But My Brother Says Big Brains Matter More" (S-S-M-M-B-M-B-S-B-B-M-B)

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PART 1: APPROACH TO THE PATIENT - BEFORE YOU EXAMINE

At the Door (Inspection from Distance)

• Facial asymmetry (drooping, wasting)
• Ptosis (CN III or Horner's)
• Squint / head tilt (CN III/IV/VI)
• Facial droop at rest (CN VII)
• Abnormal head position (torticollis - CN XI, nystagmus compensation)
• Atrophic tongue, dysarthria when speaking (CN XII, IX, X)
• Use of hearing aid (CN VIII)
• Any scars (post-surgical - parotid, mastoid, skull base)
• Skin changes: rash on ear/face (Ramsay Hunt - CN VII herpes zoster), neurofibromas (NF1/NF2)

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PART 2: HISTORY TAKING - What to Ask and Why

General Principles

Symptom-Based History Questions

Red Flag Questions

• Sudden onset? (Vascular - stroke, aneurysm)
• Severe headache? (SAH, raised ICP)
• Fever + neck stiffness? (Meningitis, encephalitis)
• Weight loss, night sweats? (Malignancy)
• Diabetes? (Mononeuropathy multiplex)
• Recent viral illness? (Bell's palsy, Ramsay Hunt, GBS)
• Any radiation to the head/neck? (Cranial nerve invasion by tumor)
• HIV/immunosuppression? (Cryptococcal meningitis, CMV)
• Trauma? (Skull base fractures)

Systemic History

• Past medical: DM, HTN, vasculitis, sarcoidosis, Lyme, MS
• Drugs: isoniazid (peripheral), phenytoin, aminoglycosides (CN VIII)
• Family history: hereditary neuropathies, NF1/NF2, Friedreich's
• Social: alcohol (thiamine - CN VI most sensitive), occupational toxins

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PART 3: THE EXAMINATION - Nerve by Nerve

Preparation

• Good lighting
• Patient seated comfortably facing you
• Have ready: pen torch, ophthalmoscope, Snellen chart, red pin, cotton wisp, orange stick/hat pin, tuning fork (128 Hz and 512 Hz), tongue blade, finger rubbing sound
• Start with hands (look for tar staining, tremor), face, then proceed systematically

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CN I - OLFACTORY NERVE

Anatomy & Course

• Type: Pure sensory
• Origin: Olfactory receptor cells in nasal mucosa (cribriform plate of ethmoid)
• Path: Olfactory filaments → cribriform plate → olfactory bulb → olfactory tract → primary olfactory cortex (uncus of temporal lobe, prepiriform cortex)
• No thalamic relay - only CN with direct cortical projection
• Memory hook: "The 1st CN goes straight to the primitive brain - no thalamus needed, like a direct hotline"

History Questions

• Loss of smell (anosmia) or distorted smell (parosmia / dysosmia)?
• One or both sides?
• Recent head trauma? Upper respiratory infection?
• Did it come on suddenly or gradually?
• Any change in taste? (Taste depends heavily on smell)

Examination

1. Ensure nasal passages are clear (blow nose)
2. Close one nostril, patient closes eyes
3. Present familiar non-pungent odors: coffee, vanilla, soap, cloves
4. Do NOT use ammonia/peppermint (trigeminal stimulants - will test CN V, not CN I)
5. Repeat other side

Positive Findings & Meaning

LMN vs UMN (not applicable for CN I - peripheral only)

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CN II - OPTIC NERVE

Anatomy & Course

• Type: Pure sensory (actually part of CNS - oligodendrocytes, not Schwann cells)
• Path: Retinal ganglion cells → optic nerve → optic chiasm → optic tract → lateral geniculate nucleus (thalamus) → optic radiation → primary visual cortex (calcarine sulcus, occipital lobe)
• At chiasm: Nasal fibers decussate; temporal fibers remain ipsilateral
• Memory hook: "The optic nerve is picky - it decussates ONLY the nasal (inner) fibers at the chiasm. Think: CROSS = NASAL"

History Questions

• Loss of vision: one eye or both? Central or peripheral?
• Sudden (vascular) or gradual (compressive, degenerative)?
• Pain on eye movement? (Optic neuritis - MS)
• Visual field defect? "Curtain coming down"? (Amaurosis fugax - TIA)
• Double vision? (Not optic nerve - that's CN III/IV/VI)
• Colour desaturation? (Optic neuritis classic - red seems washed out)
• Photopsia (flashing lights)? Floaters?

Examination

1. Visual acuity - Snellen chart, corrected; document as 6/6, 6/9, etc.; if worse, use finger counting → hand movements → light perception → no light perception
2. Colour vision - Ishihara plates; red desaturation test (compare red of pen cap in each eye)
3. Visual fields by confrontation:
   • Close your own eye, close patient's opposite eye
   • Bring white hat pin from periphery in 4 quadrants
   • Red pin detects subtle central/paracentral scotomas
4. Pupillary reactions:
   • Direct: shine light in eye → constriction
   • Consensual: light in one eye → opposite eye constricts
   • RAPD (Relative Afferent Pupillary Defect / Marcus Gunn pupil): Swinging flashlight test. Swing light rapidly from eye to eye (2 sec each). If affected eye DILATES when light shines on it = RAPD positive = optic nerve lesion that side. This is the most sensitive clinical sign of optic nerve disease.
5. Fundoscopy:
   • Optic disc: color (pale = atrophy; pink = normal; red = hyperemic in papillitis)
   • Disc margins: sharp or blurred (papilledema = blurred, elevated)
   • C:D ratio (normal <0.5)
   • Retinal vessels, hemorrhages, exudates
   • Macula: ask patient to look straight at light

Visual Field Defect Localization (MUST KNOW)

LMN vs UMN: Not applicable (optic nerve = CNS white matter tract, not a peripheral nerve)

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CN III - OCULOMOTOR NERVE

Anatomy & Course

• Type: Motor (somatic + parasympathetic)
• Origin: CN III nucleus in midbrain (at level of superior colliculus)
• Parasympathetic: Edinger-Westphal nucleus → ciliary ganglion → pupilloconstriction + accommodation
• Path: Exits ventral midbrain → runs between PCA and SCA → enters cavernous sinus (with CN IV, VI, V1, V2, sympathetics) → enters orbit through superior orbital fissure
• Muscles: Superior rectus, inferior rectus, medial rectus, inferior oblique, levator palpebrae
• Memory hook: "CN III does EVERYTHING for the eye - 4 out of 6 muscles + lid + pupil. Only SR4 and LR6 are independent" (SO4, LR6 - SO by CN IV, LR by CN VI)
• KEY CLINICAL POINT: Parasympathetic fibers run on the OUTSIDE of CN III - compressive lesions (aneurysm) hit pupil FIRST. Medical causes (diabetes) spare the pupil.

History

• Diplopia - worse in which direction?
• Ptosis?
• Headache (sudden + CN III = posterior communicating artery aneurysm until proven otherwise!)
• Diabetes?
• Head trauma?

Examination

1. Inspect pupil size and symmetry
2. Look for ptosis (levator palpebrae)
3. Test eye movements - H pattern; look for restriction
4. Pupillary light reflex: direct and consensual
5. Accommodation reflex: ask to fixate on distant then near object

CN III Palsy Signs

• Ptosis (complete or partial)
• Eye deviated "down and out" (unopposed SO and LR action)
• Diplopia in multiple directions
• Pupil-involved CN III palsy: Large fixed dilated pupil = SURGICAL emergency (PcomA aneurysm, transtentorial herniation)
• Pupil-sparing CN III palsy: Diabetes, HTN (microvascular - pupil spared because inner vascular fibers affected, outer parasympathetics spared)

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CN IV - TROCHLEAR NERVE

Anatomy & Course

• Type: Motor only
• Only CN to exit from the DORSAL aspect of the brainstem (posterior midbrain)
• Only CN to completely decussate before exiting
• Supplies: Superior oblique muscle → depresses, intorts, abducts
• Memory hook: "CN IV is the shy nerve - exits from the back, crosses completely, supplies only ONE muscle"
• Longest intracranial course → most vulnerable to trauma

Presentation

• Vertical diplopia - worse on looking down and in (e.g., going downstairs)
• Head tilt away from the affected side (to compensate)
• Bielschowsky head tilt test: Tilt head to affected side → vertical diplopia worsens

History

• Head trauma (most common cause)
• Congenital (presents in adult with old photos showing head tilt)
• Microvascular (diabetes)

Examination

• Test downward and inward gaze
• Look for hypertropia (affected eye higher)
• Head tilt test

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CN VI - ABDUCENS NERVE

Anatomy & Course

• Type: Motor only
• Origin: CN VI nucleus in the pons (floor of 4th ventricle)
• Longest intradural course → false localizing sign in raised ICP
• Supplies: Lateral rectus (abduction only)
• Memory hook: "LR6" - Lateral Rectus by CN Six

Presentation

• Horizontal diplopia - worse on ipsilateral gaze (can't abduct)
• Eye deviated medially at rest
• Patient turns head toward affected side to compensate

Examination

• Ask to look laterally to each side
• Note inability to abduct the eye
• Measure diplopia in all directions

Important Associations

• CN VI palsy + ipsilateral facial palsy (CN VII) = Millard-Gubler syndrome (pons lesion)
• CN VI palsy + ipsilateral gaze palsy = PPRF/CN VI nucleus lesion (can't look to that side at all)
• Bilateral CN VI palsies = raised ICP (false localizing sign)

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CN V - TRIGEMINAL NERVE

Anatomy & Course

• Type: Both (largest cranial nerve)
• Sensory: V1 (ophthalmic), V2 (maxillary), V3 (mandibular) - all converge to trigeminal ganglion (Gasserian ganglion, in Meckel's cave)
• Motor: V3 only → muscles of mastication (masseter, temporalis, pterygoids, mylohyoid, anterior belly of digastric)
• V1 → forehead, cornea, anterior scalp, upper nose → exits via superior orbital fissure
• V2 → cheek, upper lip, upper teeth, hard palate → exits via foramen rotundum
• V3 → lower face, lower teeth, tongue anterior 2/3 (touch, not taste), jaw → exits via foramen ovale
• Memory hook: "Standing Room Only" for exits - Superior orbital fissure, Rotundum, Ovale (V1, V2, V3)

History

• Facial numbness - exactly where? All 3 divisions or just one?
• Jaw deviation on opening?
• Pain: Is it electric-shock like, triggered by touch/eating/wind? (Trigeminal neuralgia - CN V sensory irritation)
• Corneal sensation reduced? (Dry eye, corneal ulcers)
• Hearing own voice loudly? (Tensor tympani CN V3 - normally dampens ossicles)

Examination

1. Sensory: Test light touch (cotton wisp) and pinprick in all 3 divisions bilaterally
2. Corneal reflex:
   • Afferent: CN V1 (corneal sensation) → bilateral efferent: CN VII (blink)
   • Approach from side (outside field of vision, avoid air current)
   • Normal = bilateral blink
   • If absent ipsilateral blink only = CN VII lesion; absent both blinks = CN V lesion
3. Motor:
   • Jaw clench: palpate masseter and temporalis - compare sides
   • Open mouth: jaw deviates to the side of the lesion (weak pterygoid)
4. Jaw jerk: Lower jaw tap with finger on chin → closure = brisk in UMN lesion (bilateral corticobulbar tract lesion - pseudobulbar palsy)

LMN vs UMN

• Pure CN V lesion = LMN (ipsilateral sensory loss, jaw deviation toward lesion side)
• Brisk jaw jerk + bilateral CN involvement + pseudobulbar symptoms = UMN (bilateral corticobulbar tract disease)

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CN VII - FACIAL NERVE

Anatomy & Course

• Type: Both (7 = SEVENS - Sensory, Efferent motor, Visceral motor, Efferent parasympathetic, Nerve to stapedius, Special taste)
• Motor: All muscles of facial expression + stapedius + stylohyoid + post belly digastric
• Parasympathetic: Lacrimal gland (greater petrosal nerve), submandibular and sublingual glands (chorda tympani → lingual nerve)
• Taste: Anterior 2/3 of tongue via chorda tympani
• Path: Pons nucleus → internal auditory meatus → facial canal (within petrous bone) → geniculate ganglion → exits stylomastoid foramen → parotid gland → 5 terminal branches (Temporal, Zygomatic, Buccal, Marginal mandibular, Cervical)
• Memory hook: "Ten Zebras Bit My Cat" for terminal branches

THE MOST IMPORTANT DISTINCTION IN CLINICAL NEUROLOGY:

UMN vs LMN Facial Palsy

History

• Sudden or gradual onset?
• Ear pain or vesicles in ear? (Ramsay Hunt = herpes zoster reactivation in geniculate ganglion)
• Taste loss? Hyperacusis? Dry eye? (Localizes level of lesion within facial canal)
• Recent parotid swelling or surgery?
• Viral prodrome? (Bell's palsy)
• Bilateral? (GBS, sarcoidosis, Lyme, bilateral Bell's)

Examination

1. Inspect face at rest - look for asymmetry, droop, nasolabial fold flattening
2. Raise eyebrows - wrinkle forehead (LMN: weak; UMN: preserved)
3. Close eyes tightly - try to open them (Bell's sign: eye rolls up in incomplete closure = LMN)
4. Bare teeth / Smile - lower face weakness visible in both
5. Puff cheeks - air escapes affected side
6. Whistle

Grading: House-Brackmann Scale (I = Normal, VI = Complete paralysis)

Localization of CN VII Lesion by Features

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CN VIII - VESTIBULOCOCHLEAR NERVE

Anatomy & Course

• Type: Pure sensory (2 divisions)
• Cochlear division: Organ of Corti → spiral ganglion → cochlear nucleus (pons) → superior olivary nucleus → lateral lemniscus → inferior colliculus → medial geniculate body → Heschl's gyrus (temporal lobe)
• Vestibular division: Semicircular canals + utricle/saccule → Scarpa's ganglion → vestibular nuclei (pons/medulla) → cerebellum, spinal cord, thalamus, cortex
• Memory hook: "8 = 2 ports - Hearing and Balance"

History

• Hearing loss: one or both ears? Sudden or gradual?
• Conductive vs sensorineural type? (Rinne/Weber)
• Tinnitus (ringing): unilateral? (Acoustic neuroma, Meniere's)
• Vertigo: room spinning? Positional? (BPPV vs Meniere's vs central)
• Associated facial palsy or trigeminal numbness? (CPA tumor)
• Ototoxic drugs? (Aminoglycosides, furosemide, cisplatin)

Examination

1. Whisper test: Rub fingers near each ear and compare; whispered numbers at 60 cm
2. Rinne test (512 Hz tuning fork):
   • Place on mastoid until no longer heard, then immediately in front of ear
   • Normal / Sensorineural: AC > BC (air conduction better than bone = Rinne positive)
   • Conductive hearing loss: BC > AC (Rinne negative = abnormal)
3. Weber test (512 Hz): Place on forehead/vertex
   • Normal: Heard equally both sides
   • Conductive loss: Lateralizes to AFFECTED (worse) ear
   • Sensorineural loss: Lateralizes to NORMAL (better) ear
4. Nystagmus assessment (vestibular component)
5. Romberg test, gait

Important Conditions

• Acoustic neuroma (vestibular schwannoma): Unilateral sensorineural deafness + tinnitus + vertigo; may compress CN V and VII at CPA angle
• Meniere's disease: Triad - fluctuating sensorineural hearing loss + episodic vertigo + tinnitus
• BPPV: Brief positional vertigo, no hearing loss (utricle otoconia)

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CN IX - GLOSSOPHARYNGEAL NERVE

Anatomy & Course

• Type: Both
• Motor: Stylopharyngeus (pharynx elevation during swallowing)
• Sensory: Posterior 1/3 tongue (taste + sensation), middle ear, tonsil, upper pharynx, carotid sinus and body (baroreceptors and chemoreceptors)
• Parasympathetic: Parotid gland via Jacobson's nerve → lesser petrosal nerve → otic ganglion → auriculotemporal nerve
• Path: Exits via jugular foramen (with CN X and XI)
• Memory hook: "CN 9 = NINE = NINE letters = posterior one-third tongue taste, gag reflex afferent"

History

• Difficulty swallowing (dysphagia)?
• Loss of taste at back of tongue?
• Ear pain (referred otalgia - Jacobson's nerve)?
• Unexplained syncope? (Glossopharyngeal neuralgia triggering carotid sinus hypersensitivity)
• Recurrent aspiration?

Examination

1. Gag reflex: Touch posterior pharyngeal wall with tongue blade
   • Afferent: CN IX → efferent: CN X
   • Absent bilaterally = CN X or IX problem
   • Absent on one side = that-side CN IX or X lesion
2. Taste testing: Sweet, sour, bitter, salty on posterior tongue (rarely tested clinically)

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CN X - VAGUS NERVE

Anatomy & Course

• Type: Both (widest distribution of any CN)
• Motor: Soft palate, pharynx, larynx (via recurrent and superior laryngeal nerves), upper esophagus
• Sensory: Pharynx, larynx, thoracic and abdominal viscera
• Parasympathetic: Heart (slows), lungs (bronchoconstriction), GI tract (peristalsis) to splenic flexure
• Path: Exits jugular foramen → recurrent laryngeal nerve loops around aorta (left) or subclavian (right)
• Memory hook: "VAGUS = VAGUE = goes everywhere = voice, airway, gut, heart"

History

• Hoarseness? (Recurrent laryngeal nerve)
• Dysphagia (liquids more than solids = neurogenic)?
• Nasal regurgitation? (Palate palsy)
• Bovine (non-explosive) cough?
• Features of aspiration: recurrent chest infections?
• Causes: mediastinal tumor (Pancoast, lymphoma), neck surgery (thyroid, carotid), aortic aneurysm, trauma

Examination

1. Inspect palate at rest: Uvula central?
2. Say "Ahh": Palate should rise symmetrically; uvula deviates AWAY from the lesion (toward normal side)
3. Phonation: Hoarseness, "hot potato voice"
4. Listen for bovine cough
5. Indirect laryngoscopy if available

CN X Palsy

• Unilateral: hoarseness + palate asymmetry, mild dysphagia
• Bilateral: severe dysphagia, aspiration, risk of respiratory compromise
• Bulbar palsy: LMN CN IX/X/XII lesion - flaccid palate, nasal voice, wasted fasciculating tongue
• Pseudobulbar palsy: UMN bilateral lesion - spastic palate, brisk jaw jerk, emotional lability, dysarthria (spastic quality), NO fasciculations

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CN XI - SPINAL ACCESSORY NERVE

Anatomy & Course

• Type: Pure motor
• Unique: Has both cranial and spinal roots
• Cranial root: Exits medulla (small contribution, joins vagus)
• Spinal root: C1-C5 anterior horn cells → spinal root ascends through foramen magnum → exits jugular foramen → supplies sternocleidomastoid (SCM) + trapezius
• Memory hook: "XI - Shrug and Turn - Trap and SCM"

History

• Difficulty turning head to one side?
• Weakness raising arm above horizontal? (Trapezius weakness → impaired scapular rotation)
• Shoulder drooping?
• Neck surgery or lymph node biopsy? (CN XI runs superficially in posterior triangle - vulnerable to surgery!)

Examination

1. Trapezius: Ask to shrug shoulders against resistance (examiner pushes down on shoulders)
   • Weak trapezius = shoulder drops, scapular winging possible
2. SCM: Ask to turn head to opposite side against resistance (examiner's hand on jaw)
   • SCM contracts on OPPOSITE side to head turn
   • Test right head turn to assess left SCM and vice versa

Key Points

• CN XI lesion = ipsilateral trapezius + SCM weakness
• Trapezius more important clinically (winging of scapula, inability to abduct arm above 90°)
• Posterior triangle iatrogenic injury is the commonest cause

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CN XII - HYPOGLOSSAL NERVE

Anatomy & Course

• Type: Pure motor
• Supplies: All intrinsic and extrinsic tongue muscles EXCEPT palatoglossus (CN X)
• Path: Hypoglossal canal (own canal in occipital bone) → passes through submandibular triangle
• Memory hook: "XII tongue, exits own canal, tongue deviates TO the lesion (LMN)"

History

• Slurred speech? (Dysarthria - lingual consonants l, t, d affected)
• Difficulty chewing or swallowing?
• Unilateral tongue wasting?
• Occipital bone or posterior fossa lesion? Carotid dissection? Neck surgery?

Examination

1. Inspect tongue at rest: Look for:
   • Wasting / atrophy (LMN)
   • Fasciculations (LMN - lower motor neuron disease)
2. Protrude tongue: Tongue deviates TOWARD the weak side (toward the lesion) in LMN
3. Strength: Push tongue into each cheek against examiner's finger externally
4. Rapid alternating movement: "la-la-la"

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PART 4: UMN vs LMN - THE CORE CONCEPT

Understanding the Two Systems

• Cell body: Motor cortex (precentral gyrus)
• Axon travels: Internal capsule → cerebral peduncle → decussates at medullary pyramids → lateral corticospinal tract
• Synapses on: anterior horn cell (spinal cord) or cranial nerve motor nuclei (brainstem)
• The UMN INHIBITS spinal reflexes. When UMN is lost → reflex arcs are released → SPASTICITY + HYPERREFLEXIA

• Cell body: Anterior horn cell (spinal) or cranial nerve nucleus (brainstem)
• Axon travels: Peripheral nerve → neuromuscular junction → muscle
• When lost → direct denervation → FLACCIDITY + AREFLEXIA + WASTING + FASCICULATIONS

Classic UMN vs LMN Comparison Table

Memory Hook: UMN = "SHAFT" - Spasticity, Hyperreflexia, Absence of wasting, Flexor posture arms/Extensor legs, Toes upgoing (Babinski)

LMN = "WFAR" - Wasting, Flaccidity, Areflexia, Really visible fasciculations

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PART 5: CLINICAL DIFFERENTIATION OF FACIAL PALSY (THE EXAM FAVOURITE)

Step-by-Step Approach at Bedside

1. Look at forehead: Can the patient raise eyebrows and wrinkle forehead?
   • YES (forehead spared) = UMN (stroke, tumor, MS)
   • NO (forehead involved) = LMN (Bell's palsy, Ramsay Hunt, parotid, CPA tumor)
2. Ask about taste loss: Absent = LMN (above chorda tympani)
3. Ask about ear pain / vesicles: Present = Ramsay Hunt syndrome
4. Ask about hyperacusis: Present = nerve to stapedius involved (within facial canal)
5. Ask about dry eye: Present = above geniculate ganglion (severe LMN)
6. Look for other CN involvement:
   • • CN VIII loss = CPA angle tumor (acoustic neuroma)
   • • CN VI palsy = pontine lesion
   • • Contralateral hemiplegia = brainstem stroke
7. Look for emotional vs voluntary dissociation:
   • UMN lesion → can smile spontaneously (emotional pathways intact from basal ganglia) but cannot smile on command
   • Basal ganglia lesion (Parkinson's) → cannot smile emotionally but can smile voluntarily

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PART 6: BULBAR vs PSEUDOBULBAR PALSY (HIGH-YIELD)

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PART 7: SYNDROMES YOU MUST KNOW

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PART 8: WHAT ELSE TO KNOW - EXTRAS THE EXAMINER MIGHT PROBE

Horner's Syndrome (Sympathetic Pathway - not a cranial nerve but always asked)

• Triad: Ptosis + Miosis + Anhidrosis (± enophthalmos apparent)
• Central Horner (1st order): Hypothalamus → ciliospinal center (C8-T2) - Lateral medullary stroke, syrinx
• Preganglionic (2nd order): C8-T2 → superior cervical ganglion - Pancoast tumor, cervical rib, neck dissection
• Postganglionic (3rd order): Superior cervical ganglion → orbit - Carotid dissection, cavernous sinus lesion, cluster headache
• Pharmacological testing: Cocaine drops (confirm Horner's), Hydroxyamphetamine (differentiate pre/postganglionic)

Internuclear Ophthalmoplegia (INO)

• Lesion in the medial longitudinal fasciculus (MLF)
• Impaired adduction ipsilateral to lesion + nystagmus of abducting eye
• One-and-a-half syndrome: MLF + PPRF lesion → ipsilateral gaze palsy + ipsilateral INO; only movement = contralateral abduction
• Most common cause: MS (bilateral INO), brainstem stroke (unilateral)

Argyll Robertson Pupil (Neurosyphilis)

• Small, irregular, unequal pupils
• Accommodate but do NOT react (ACCOMODATES BUT DOESN'T REACT = "Prostitute's pupil")
• Lesion: pretectal region

Light-Near Dissociation (pupil accommodates but not reactive to light)

• Argyll Robertson (neurosyphilis), dorsal midbrain syndrome (Parinaud), diabetic autonomic neuropathy, Adie's tonic pupil

Adie's Tonic Pupil

• Large pupil, reacts slowly to light, better accommodation
• Absent deep tendon reflexes (Holmes-Adie syndrome)
• Young women, benign, ciliary ganglion lesion

Nystagmus - Quick Guide

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PART 9: SUMMARY EXAMINATION SEQUENCE (For Long Case)

1. Inspection at rest: Asymmetry, ptosis, squint, droop, skin lesions
2. CN I: Olfaction (omit unless indicated)
3. CN II: Acuity, fields (confrontation), pupil (RAPD), fundoscopy
4. CN III/IV/VI: Pupils, ptosis, eye movements (H pattern), diplopia assessment
5. CN V: Facial sensation (3 divisions), corneal reflex, jaw clench, jaw opening (deviation?), jaw jerk
6. CN VII: Forehead wrinkle, eye closure, smile, puff cheeks, Bell's phenomenon
7. CN VIII: Finger rub, Rinne, Weber, nystagmus
8. CN IX/X: Palate at rest, "ahh" (uvula), gag reflex, voice quality, swallowing
9. CN XI: Shoulder shrug (trapezius), head rotation (SCM)
10. CN XII: Tongue at rest (wasting, fasciculations), protrusion, strength, rapid movements

• Motor (tone, power, reflexes, plantars)
• Sensory (if indicated)
• Cerebellar (if indicated)
• Gait

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PART 10: COMMON CAUSES QUICK REFERENCE

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