The Cranial Nerve Connection

The Cranial Nerve Connection The Cranial Nerve Connection The Cranial Nerve Connection The Cranial Nerve Connection

Leonid Skorin, Jr., OD, DO, MS, FAAO, FAOCOLeonid Skorin, Jr., OD, DO, MS, FAAO, FAOCO

Consultant, Department of SurgeryConsultant, Department of Surgery

Community Division of OphthalmologyCommunity Division of Ophthalmology

Mayo Clinic Health System in Albert LeaMayo Clinic Health System in Albert Lea

Assistant Professor OphthalmologyAssistant Professor OphthalmologyMayo Clinic College of MedicineMayo Clinic College of Medicine

Leonid Skorin, Jr., OD, DO, MS, FAAO, FAOCOLeonid Skorin, Jr., OD, DO, MS, FAAO, FAOCO

Consultant, Department of SurgeryConsultant, Department of Surgery

Community Division of OphthalmologyCommunity Division of Ophthalmology

Mayo Clinic Health System in Albert LeaMayo Clinic Health System in Albert Lea

Assistant Professor OphthalmologyAssistant Professor OphthalmologyMayo Clinic College of MedicineMayo Clinic College of Medicine

Cranial Nerve 1 Cranial Nerve 1 –– Olfactory NerveOlfactory NerveCranial Nerve 1 Cranial Nerve 1 –– Olfactory NerveOlfactory Nerve

1.1. Testing Testing –– patient shuts eyespatient shuts eyes

•• Examiner occludes one nostrilExaminer occludes one nostril

•• Test each nostril separatelyTest each nostril separately

•• Identify coffee, tobacco, peppermint, vanillaIdentify coffee, tobacco, peppermint, vanilla

•• Do not test noxious odors such as ammoniaDo not test noxious odors such as ammonia

•• Function of mucous membranes of nose Function of mucous membranes of nose NOT olfactory nerveNOT olfactory nerve

•• Unreliable test Unreliable test -- Rarely performedRarely performed

1.1. Testing Testing –– patient shuts eyespatient shuts eyes

•• Examiner occludes one nostrilExaminer occludes one nostril

•• Test each nostril separatelyTest each nostril separately

•• Identify coffee, tobacco, peppermint, vanillaIdentify coffee, tobacco, peppermint, vanilla

•• Do not test noxious odors such as ammoniaDo not test noxious odors such as ammonia

•• Function of mucous membranes of nose Function of mucous membranes of nose NOT olfactory nerveNOT olfactory nerve

•• Unreliable test Unreliable test -- Rarely performedRarely performed


2. 2. ResultsResults

•• AnosmiaAnosmia –– loss of sense of smellloss of sense of smell

•• Bilateral loss Bilateral loss –– agingaging

•• Unilateral loss Unilateral loss –– trauma to trauma to cribriformcribriform plateplate

a.a. blocked nasal passagesblocked nasal passages

b.b. FosterFoster--Kennedy syndromeKennedy syndrome

1)1) anosmiaanosmia

2)2) dementiadementia

3)3) unilateral optic atrophyunilateral optic atrophy

4)4) contralateralcontralateral disc edemadisc edema

5)5) etiology: etiology: subfrontalsubfrontal mass (olfactory groove mass (olfactory groove meningiomameningioma))

2. 2. ResultsResults

•• AnosmiaAnosmia –– loss of sense of smellloss of sense of smell

•• Bilateral loss Bilateral loss –– agingaging

•• Unilateral loss Unilateral loss –– trauma to trauma to cribriformcribriform plateplate

a.a. blocked nasal passagesblocked nasal passages

b.b. FosterFoster--Kennedy syndromeKennedy syndrome

1)1) anosmiaanosmia

2)2) dementiadementia

3)3) unilateral optic atrophyunilateral optic atrophy

4)4) contralateralcontralateral disc edemadisc edema

5)5) etiology: etiology: subfrontalsubfrontal mass (olfactory groove mass (olfactory groove meningiomameningioma))


Cranial Nerve 2 Cranial Nerve 2 –– Optic NerveOptic NerveCranial Nerve 2 Cranial Nerve 2 –– Optic NerveOptic Nerve

1.1. TestingTesting

•• Visual acuityVisual acuity

•• Visual fieldsVisual fields

•• Color visionColor vision

•• Pupil testingPupil testing

a)a) direct light reflexdirect light reflex

b)b) consensual light reflexconsensual light reflex

c)c) swinging flashlight testswinging flashlight test

d)d) near reflexnear reflex

1.1. TestingTesting

•• Visual acuityVisual acuity

•• Visual fieldsVisual fields

•• Color visionColor vision

•• Pupil testingPupil testing

a)a) direct light reflexdirect light reflex

b)b) consensual light reflexconsensual light reflex

c)c) swinging flashlight testswinging flashlight test

d)d) near reflexnear reflex


•• 64 64 y.oy.o. WF, optic nerve edema LT. WF, optic nerve edema LT

•• Blurred vision, grey inferior VF, LTBlurred vision, grey inferior VF, LT

•• Negative medical Negative medical HxHx, nonsmoker , nonsmoker

•• Family Family HxHx: CVA, HTN, fatal : CVA, HTN, fatal valvularvalvular heart heart dzdz

•• 20/2020/20--11 RT, 20/40RT, 20/40+2+2 LTLT

•• 0.3 log units LT RAPD0.3 log units LT RAPD

•• Red color saturation equalRed color saturation equal

•• External/SLE negativeExternal/SLE negative

•• BP: 158/95 mm HgBP: 158/95 mm Hg

•• All blood test negative except cholesterol: All blood test negative except cholesterol: 240 mg/240 mg/dLdL, HDL 73 mg/, HDL 73 mg/dLdL

•• 64 64 y.oy.o. WF, optic nerve edema LT. WF, optic nerve edema LT

•• Blurred vision, grey inferior VF, LTBlurred vision, grey inferior VF, LT

•• Negative medical Negative medical HxHx, nonsmoker , nonsmoker

•• Family Family HxHx: CVA, HTN, fatal : CVA, HTN, fatal valvularvalvular heart heart dzdz

•• 20/2020/20--11 RT, 20/40RT, 20/40+2+2 LTLT

•• 0.3 log units LT RAPD0.3 log units LT RAPD

•• Red color saturation equalRed color saturation equal

•• External/SLE negativeExternal/SLE negative

•• BP: 158/95 mm HgBP: 158/95 mm Hg

•• All blood test negative except cholesterol: All blood test negative except cholesterol: 240 mg/240 mg/dLdL, HDL 73 mg/, HDL 73 mg/dLdL


•• FundusFundus: crowded discs, LT superior : crowded discs, LT superior sectoralsectoral edema, edema, blurred superior disc marginsblurred superior disc margins

•• OCT: superior nerve fiber swelling LTOCT: superior nerve fiber swelling LT

•• FundusFundus: crowded discs, LT superior : crowded discs, LT superior sectoralsectoral edema, edema, blurred superior disc marginsblurred superior disc margins

•• OCT: superior nerve fiber swelling LTOCT: superior nerve fiber swelling LT


•• VF: absolute VF: absolute infranasalinfranasal altitudinal defectaltitudinal defect

•• CT of head/orbit:CT of head/orbit:negativenegative

•• VF: absolute VF: absolute infranasalinfranasal altitudinal defectaltitudinal defect

•• CT of head/orbit:CT of head/orbit:negativenegative


•• Seen by internist 1 week laterSeen by internist 1 week later

•• BP: 132/82BP: 132/82

•• Rx: 81 mg ASA dailyRx: 81 mg ASA daily

•• CarotidCarotid US US –– no no stenosisstenosis

•• Seen again at eye clinic 5 weeks laterSeen again at eye clinic 5 weeks later

•• RAPD and VF sameRAPD and VF same

•• BP: 140/82BP: 140/82

•• FundusFundus sectoralsectoral edema:edema:mostly resolvedmostly resolved

•• Seen by internist 1 week laterSeen by internist 1 week later

•• BP: 132/82BP: 132/82

•• Rx: 81 mg ASA dailyRx: 81 mg ASA daily

•• CarotidCarotid US US –– no no stenosisstenosis

•• Seen again at eye clinic 5 weeks laterSeen again at eye clinic 5 weeks later

•• RAPD and VF sameRAPD and VF same

•• BP: 140/82BP: 140/82

•• FundusFundus sectoralsectoral edema:edema:mostly resolvedmostly resolved


•• NAION: acute, unilateral, painless vision lossNAION: acute, unilateral, painless vision loss

•• Older than 50 years, CaucasianOlder than 50 years, Caucasian

•• Disc at riskDisc at risk

•• Inferior altitudinal VF defectInferior altitudinal VF defect

•• Risk factors:Risk factors:

a)a) hypertensionhypertension

b)b) nocturnal hypotensionnocturnal hypotension

c)c) hyperlipidemiahyperlipidemia

d)d) diabetesdiabetes

e)e) obstructive sleep apneaobstructive sleep apnea

f)f) smokingsmoking

g)g) PDEPDE--5 inhibitor use (Viagra, 5 inhibitor use (Viagra, CialisCialis, , LevitraLevitra))

•• NAION: acute, unilateral, painless vision lossNAION: acute, unilateral, painless vision loss

•• Older than 50 years, CaucasianOlder than 50 years, Caucasian

•• Disc at riskDisc at risk

•• Inferior altitudinal VF defectInferior altitudinal VF defect

•• Risk factors:Risk factors:

a)a) hypertensionhypertension

b)b) nocturnal hypotensionnocturnal hypotension

c)c) hyperlipidemiahyperlipidemia

d)d) diabetesdiabetes

e)e) obstructive sleep apneaobstructive sleep apnea

f)f) smokingsmoking

g)g) PDEPDE--5 inhibitor use (Viagra, 5 inhibitor use (Viagra, CialisCialis, , LevitraLevitra))


•• White coat HTN: inWhite coat HTN: in--office BP > 140/90office BP > 140/90

•• Masked HTN: inMasked HTN: in--office BP < 140/90 but office BP < 140/90 but elevated at homeelevated at home

•• Increased risk of developing sustained HTN Increased risk of developing sustained HTN over 10 yearsover 10 years

•• Additional family Additional family hxhx::

a)a) all siblings have HTNall siblings have HTN

b)b) one had NAIONone had NAION

c)c) one had CRAOone had CRAO

•• White coat HTN: inWhite coat HTN: in--office BP > 140/90office BP > 140/90

•• Masked HTN: inMasked HTN: in--office BP < 140/90 but office BP < 140/90 but elevated at homeelevated at home

•• Increased risk of developing sustained HTN Increased risk of developing sustained HTN over 10 yearsover 10 years

•• Additional family Additional family hxhx::

a)a) all siblings have HTNall siblings have HTN

b)b) one had NAIONone had NAION

c)c) one had CRAOone had CRAO

Hypertension definition Hypertension definition Joint National Committee 7Joint National Committee 7

Hypertension definition Hypertension definition Joint National Committee 7Joint National Committee 7

•• JNC7 defines normal JNC7 defines normal blood blood pressure as <120/<pressure as <120/<80 80 mmHgmmHg

•• PrePre--hypertensionhypertension: : 120120--139 systolic or 80139 systolic or 80--89 mmHg 89 mmHg diastolicdiastolic

•• Hypertension:Hypertension:•• Stage Stage 1: 1: 140140--159/90159/90--99 mmHg99 mmHg•• Stage Stage 2: 2: ≥160 systolic ≥160 systolic or or diastolic ≥diastolic ≥100 100 mmHgmmHg

**Requires screening measurement and average of **Requires screening measurement and average of two follow up measurements**two follow up measurements**

•• JNC7 defines normal JNC7 defines normal blood blood pressure as <120/<pressure as <120/<80 80 mmHgmmHg

•• PrePre--hypertensionhypertension: : 120120--139 systolic or 80139 systolic or 80--89 mmHg 89 mmHg diastolicdiastolic

•• Hypertension:Hypertension:•• Stage Stage 1: 1: 140140--159/90159/90--99 mmHg99 mmHg•• Stage Stage 2: 2: ≥160 systolic ≥160 systolic or or diastolic ≥diastolic ≥100 100 mmHgmmHg

**Requires screening measurement and average of **Requires screening measurement and average of two follow up measurements**two follow up measurements**

Joint National Committee 8Joint National Committee 8Joint National Committee 8Joint National Committee 8

•• Did not address HTN definitions…..preDid not address HTN definitions…..pre--HTN, HTN, stage 1, 2 etc….stage 1, 2 etc….

•• Focus now on Focus now on goals:goals:

•• ≥60 years old ≥60 years old –– treat if BP treat if BP ≥ 150/90≥ 150/90•• <60 years old <60 years old –– treat if BP treat if BP ≥ 140/90≥ 140/90•• DM or CKD DM or CKD –– treat if BP treat if BP ≥ 140/90≥ 140/90

•• Did not address HTN definitions…..preDid not address HTN definitions…..pre--HTN, HTN, stage 1, 2 etc….stage 1, 2 etc….

•• Focus now on Focus now on goals:goals:

•• ≥60 years old ≥60 years old –– treat if BP treat if BP ≥ 150/90≥ 150/90•• <60 years old <60 years old –– treat if BP treat if BP ≥ 140/90≥ 140/90•• DM or CKD DM or CKD –– treat if BP treat if BP ≥ 140/90≥ 140/90

JNC8.

Cranial Nerve 3 Cranial Nerve 3 –– OculomotorOculomotor Nerve Nerve Cranial Nerve 3 Cranial Nerve 3 –– OculomotorOculomotor Nerve Nerve

1.1. TestingTesting

A.A. Somatic motor controlsSomatic motor controls

•• Superior, inferior, medial rectus musclesSuperior, inferior, medial rectus muscles

•• Inferior oblique muscleInferior oblique muscle

•• Levator Levator palpebraepalpebrae superiorissuperioris musclemuscle

B. B. Parasympathetic motorParasympathetic motor

•• Innervates fibers that control Innervates fibers that control ciliaryciliary body body and iris sphincterand iris sphincter

1.1. TestingTesting

A.A. Somatic motor controlsSomatic motor controls

•• Superior, inferior, medial rectus musclesSuperior, inferior, medial rectus muscles

•• Inferior oblique muscleInferior oblique muscle

•• Levator Levator palpebraepalpebrae superiorissuperioris musclemuscle

B. B. Parasympathetic motorParasympathetic motor

•• Innervates fibers that control Innervates fibers that control ciliaryciliary body body and iris sphincterand iris sphincter

Cranial Nerve 3 Cranial Nerve 3 –– OculomotorOculomotor NerveNerveCranial Nerve 3 Cranial Nerve 3 –– OculomotorOculomotor NerveNerve

2.2. ResultsResults

•• HypodeviatedHypodeviated and and exotropicexotropic “down and “down and out”out”

•• PtosisPtosis

•• Difficulty accommodating Difficulty accommodating

2.2. ResultsResults

•• HypodeviatedHypodeviated and and exotropicexotropic “down and “down and out”out”

•• PtosisPtosis

•• Difficulty accommodating Difficulty accommodating


2.2. ResultsResults

•• Pupil dilationPupil dilation

a.a. benign ischemic infarctionbenign ischemic infarction

b.b. compression from enlarging aneurysm at compression from enlarging aneurysm at the junction of the carotid and posterior the junction of the carotid and posterior communicating arteriescommunicating arteries

2.2. ResultsResults

•• Pupil dilationPupil dilation

a.a. benign ischemic infarctionbenign ischemic infarction

b.b. compression from enlarging aneurysm at compression from enlarging aneurysm at the junction of the carotid and posterior the junction of the carotid and posterior communicating arteriescommunicating arteries


•• 65 65 y.oy.o. WF . WF –– acute, RT lid ptosis, binocular acute, RT lid ptosis, binocular diplopiadiplopia

•• Dull pain behind RT eye and upper lidDull pain behind RT eye and upper lid

•• Diabetic Type II, HTN, Diabetic Type II, HTN, hyperlipidemiahyperlipidemia, hypothyroid, hypothyroid

•• VA: 20/20VA: 20/20--11 RT, 20/15 LTRT, 20/15 LT

•• Pupil normal, no RAPDPupil normal, no RAPD

•• Motility Motility –– down and out with ptosisdown and out with ptosis

•• 65 65 y.oy.o. WF . WF –– acute, RT lid ptosis, binocular acute, RT lid ptosis, binocular diplopiadiplopia

•• Dull pain behind RT eye and upper lidDull pain behind RT eye and upper lid

•• Diabetic Type II, HTN, Diabetic Type II, HTN, hyperlipidemiahyperlipidemia, hypothyroid, hypothyroid

•• VA: 20/20VA: 20/20--11 RT, 20/15 LTRT, 20/15 LT

•• Pupil normal, no RAPDPupil normal, no RAPD

•• Motility Motility –– down and out with ptosisdown and out with ptosis


•• VF, color testing, sinus transillumination, SLE, VF, color testing, sinus transillumination, SLE, fundusfundus all normalall normal

•• HbA1C 6.2%, BS 103, CRP 10 mg/L, BP 139/71HbA1C 6.2%, BS 103, CRP 10 mg/L, BP 139/71

•• ICE test ICE test –– negativenegative

•• Temporal artery biopsy Temporal artery biopsy –– negativenegative

•• MRI and MRA of brain MRI and MRA of brain -- negativenegative

•• VF, color testing, sinus transillumination, SLE, VF, color testing, sinus transillumination, SLE, fundusfundus all normalall normal

•• HbA1C 6.2%, BS 103, CRP 10 mg/L, BP 139/71HbA1C 6.2%, BS 103, CRP 10 mg/L, BP 139/71

•• ICE test ICE test –– negativenegative

•• Temporal artery biopsy Temporal artery biopsy –– negativenegative

•• MRI and MRA of brain MRI and MRA of brain -- negativenegative


•• MicrovascularMicrovascular ischemic 3ischemic 3rdrd nerve palsynerve palsy

•• Our patient had multiple risk factorsOur patient had multiple risk factors

•• PeriorbitalPeriorbital pain common pain common –– due to hypoxiadue to hypoxia

•• Resolves in 8 Resolves in 8 –– 12 weeks12 weeks

•• Always monitor for later pupil involvementAlways monitor for later pupil involvement

•• MicrovascularMicrovascular ischemic 3ischemic 3rdrd nerve palsynerve palsy

•• Our patient had multiple risk factorsOur patient had multiple risk factors

•• PeriorbitalPeriorbital pain common pain common –– due to hypoxiadue to hypoxia

•• Resolves in 8 Resolves in 8 –– 12 weeks12 weeks

•• Always monitor for later pupil involvementAlways monitor for later pupil involvement

Cranial Nerve 4 Cranial Nerve 4 –– TrochlearTrochlear NerveNerveCranial Nerve 4 Cranial Nerve 4 –– TrochlearTrochlear NerveNerve

1.1. TestingTesting

A.A. Somatic controlSomatic control

•• Controls superior oblique muscleControls superior oblique muscle

ParksParks--BielschowskyBielschowsky 33--Step TestStep Test

double Maddox rod test for double Maddox rod test for cyclodeviationcyclodeviation

Maddox WingMaddox Wing

B.B. ResultsResults

•• DiplopiaDiplopia –– vertical, diagonal or vertical, diagonal or incyclotorsionalincyclotorsional, worse when reading, worse when reading

•• Head tilt to opposite sideHead tilt to opposite side

•• HyperdeviationHyperdeviation worse on worse on contralateralcontralateral gaze, gaze, down gaze and down gaze and ipsilateralipsilateral head tilthead tilt

1.1. TestingTesting

A.A. Somatic controlSomatic control

•• Controls superior oblique muscleControls superior oblique muscle

ParksParks--BielschowskyBielschowsky 33--Step TestStep Test

double Maddox rod test for double Maddox rod test for cyclodeviationcyclodeviation

Maddox WingMaddox Wing

B.B. ResultsResults

•• DiplopiaDiplopia –– vertical, diagonal or vertical, diagonal or incyclotorsionalincyclotorsional, worse when reading, worse when reading

•• Head tilt to opposite sideHead tilt to opposite side

•• HyperdeviationHyperdeviation worse on worse on contralateralcontralateral gaze, gaze, down gaze and down gaze and ipsilateralipsilateral head tilthead tilt

Cranial Nerve 4 Cranial Nerve 4 –– TrochlearTrochlear NerveNerve

On Straight Gaze: On Straight Gaze: hyperdeviationhyperdeviation of right eye of right eye On Adduction & Upgaze: On Adduction & Upgaze: overactionoveraction of I.O. of I.O.

On Adduction and Depression: On Adduction and Depression: underactionunderaction of S.O.of S.O.Head Tilt to the Opposite Side Head Tilt to the Opposite Side

Cranial Nerve 4 Cranial Nerve 4 –– TrochlearTrochlear NerveNerve

On Straight Gaze: On Straight Gaze: hyperdeviationhyperdeviation of right eye of right eye On Adduction & Upgaze: On Adduction & Upgaze: overactionoveraction of I.O. of I.O.

On Adduction and Depression: On Adduction and Depression: underactionunderaction of S.O.of S.O.Head Tilt to the Opposite Side Head Tilt to the Opposite Side

Cranial Nerve 4 Cranial Nerve 4 –– TrochlearTrochlear NerveNerveCranial Nerve 4 Cranial Nerve 4 –– TrochlearTrochlear NerveNerve Cranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal NerveCranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal Nerve

•• Sensory Sensory –– light touch, pain, pressure, temperaturelight touch, pain, pressure, temperature

•• Corneal reflex test Corneal reflex test –– sensory 5 & motor 7 lid closuresensory 5 & motor 7 lid closure

•• Ophthalmic, Maxillary, Ophthalmic, Maxillary, MandibularMandibular

•• Orbital floor blowout fracture: Orbital floor blowout fracture: infraorbitalinfraorbital nerve nerve hypesthesiahypesthesiaor anesthesia of or anesthesia of ipsilateralipsilateral cheek and upper lipcheek and upper lip

•• Sensory Sensory –– light touch, pain, pressure, temperaturelight touch, pain, pressure, temperature

•• Corneal reflex test Corneal reflex test –– sensory 5 & motor 7 lid closuresensory 5 & motor 7 lid closure

•• Ophthalmic, Maxillary, Ophthalmic, Maxillary, MandibularMandibular

•• Orbital floor blowout fracture: Orbital floor blowout fracture: infraorbitalinfraorbital nerve nerve hypesthesiahypesthesiaor anesthesia of or anesthesia of ipsilateralipsilateral cheek and upper lipcheek and upper lip

Cranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal NerveCranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal Nerve

•• Motor Motor –– temporal, masseter, pterygoid musclestemporal, masseter, pterygoid muscles

•• Jaw deviates toward side of weaknessJaw deviates toward side of weakness

•• Motor Motor –– temporal, masseter, pterygoid musclestemporal, masseter, pterygoid muscles

•• Jaw deviates toward side of weaknessJaw deviates toward side of weakness


1.1. Herpetic neuralgiaHerpetic neuralgia

•• Pain is severe, burning, achingPain is severe, burning, aching

•• Pain precedes rash by 4 Pain precedes rash by 4 –– 7 days7 days

•• Distribution of dermatome (HZO)Distribution of dermatome (HZO)

•• PseudodentritesPseudodentrites, , iridocyclitisiridocyclitis

•• Hutchinson’s sign Hutchinson’s sign ––nasociliarynasociliary branchbranch

•• Pain regresses 1 Pain regresses 1 –– 2 weeks2 weeks

•• PostPost--herpetic neuralgia herpetic neuralgia ––persists months to yearspersists months to years

1.1. Herpetic neuralgiaHerpetic neuralgia

•• Pain is severe, burning, achingPain is severe, burning, aching

•• Pain precedes rash by 4 Pain precedes rash by 4 –– 7 days7 days

•• Distribution of dermatome (HZO)Distribution of dermatome (HZO)

•• PseudodentritesPseudodentrites, , iridocyclitisiridocyclitis

•• Hutchinson’s sign Hutchinson’s sign ––nasociliarynasociliary branchbranch

•• Pain regresses 1 Pain regresses 1 –– 2 weeks2 weeks

•• PostPost--herpetic neuralgia herpetic neuralgia ––persists months to yearspersists months to years

Cranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal NerveCranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal Nerve Cranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal NerveCranial Nerve 5 Cranial Nerve 5 –– Trigeminal NerveTrigeminal Nerve

•• 50 50 y.oy.o. WM pain behind RT eye. WM pain behind RT eye

•• Pain in RT temple and Pain in RT temple and periocularperiocular regionregion

•• Mild blurring right eyeMild blurring right eye

•• Denies migraines or cluster headachesDenies migraines or cluster headaches

•• VA 20/20 RT/LTVA 20/20 RT/LT

•• Pupils: 1mm Pupils: 1mm anisocoriaanisocoria in light, ↑ to 2mm darkin light, ↑ to 2mm dark

•• Pupils: no RAPDPupils: no RAPD

•• 3mm ptosis RUL3mm ptosis RUL

•• 50 50 y.oy.o. WM pain behind RT eye. WM pain behind RT eye

•• Pain in RT temple and Pain in RT temple and periocularperiocular regionregion

•• Mild blurring right eyeMild blurring right eye

•• Denies migraines or cluster headachesDenies migraines or cluster headaches

•• VA 20/20 RT/LTVA 20/20 RT/LT

•• Pupils: 1mm Pupils: 1mm anisocoriaanisocoria in light, ↑ to 2mm darkin light, ↑ to 2mm dark

•• Pupils: no RAPDPupils: no RAPD

•• 3mm ptosis RUL3mm ptosis RUL


•• MRI/MRA/carotid US/CXR MRI/MRA/carotid US/CXR –– negativenegative

•• 1% 1% phenylephrinephenylephrine –– reduced ptosis by 2mm and reduced ptosis by 2mm and dilated pupil by 2mm; dilated pupil by 2mm; denervationdenervation hypersensitivity. hypersensitivity. 71% sensitive to 1% NS. Normal pupil does not 71% sensitive to 1% NS. Normal pupil does not dilate. Substitute for dilate. Substitute for hydroxyamphetaminehydroxyamphetamine 1%.1%.

•• Confirms postConfirms post--ganglionicganglionic (third order) Horner’s(third order) Horner’s

•• DxDx –– Raeder’s Raeder’s paratrigeminalparatrigeminal neuralgia: 5neuralgia: 5thth C.N. C.N. pain distribution with Horner’s syndromepain distribution with Horner’s syndrome

•• TxTx –– gabapentingabapentin, , tegretoltegretol, , baclofenbaclofen

•• MRI/MRA/carotid US/CXR MRI/MRA/carotid US/CXR –– negativenegative

•• 1% 1% phenylephrinephenylephrine –– reduced ptosis by 2mm and reduced ptosis by 2mm and dilated pupil by 2mm; dilated pupil by 2mm; denervationdenervation hypersensitivity. hypersensitivity. 71% sensitive to 1% NS. Normal pupil does not 71% sensitive to 1% NS. Normal pupil does not dilate. Substitute for dilate. Substitute for hydroxyamphetaminehydroxyamphetamine 1%.1%.

•• Confirms postConfirms post--ganglionicganglionic (third order) Horner’s(third order) Horner’s

•• DxDx –– Raeder’s Raeder’s paratrigeminalparatrigeminal neuralgia: 5neuralgia: 5thth C.N. C.N. pain distribution with Horner’s syndromepain distribution with Horner’s syndrome

•• TxTx –– gabapentingabapentin, , tegretoltegretol, , baclofenbaclofen

Cranial Nerve 6 Cranial Nerve 6 –– AbducensAbducens NerveNerveCranial Nerve 6 Cranial Nerve 6 –– AbducensAbducens NerveNerve

1.1. TestingTesting

A.A. Somatic motorSomatic motor

•• Controls lateral rectus muscleControls lateral rectus muscle

2.2. ResultsResults

A.A. DiplopiaDiplopia –– worse when looking laterally at distanceworse when looking laterally at distance

1.1. TestingTesting

A.A. Somatic motorSomatic motor

•• Controls lateral rectus muscleControls lateral rectus muscle

2.2. ResultsResults

A.A. DiplopiaDiplopia –– worse when looking laterally at distanceworse when looking laterally at distance

Cranial Nerve 6 Cranial Nerve 6 –– AbducensAbducens NerveNerveCranial Nerve 6 Cranial Nerve 6 –– AbducensAbducens NerveNerve

3.3. WorkWork--up and management (Nerves 3, 4, 6)up and management (Nerves 3, 4, 6)

A.A. Patients under 50Patients under 50

•• MRI/MRAMRI/MRA

•• Blood tests (FBS, ANA, RPR, Lyme titer, ESR)Blood tests (FBS, ANA, RPR, Lyme titer, ESR)

•• Lumbar punctureLumbar puncture

B.B. Patients over 50Patients over 50

•• Atherosclerosis evaluationAtherosclerosis evaluation

•• ESR, CRP, platelets for temporal arteritisESR, CRP, platelets for temporal arteritis

•• Consider MRI/MRAConsider MRI/MRA

C.C. Don’t forgetDon’t forget•• Myasthenia gravisMyasthenia gravis

•• Thyroid ophthalmopathyThyroid ophthalmopathy

3.3. WorkWork--up and management (Nerves 3, 4, 6)up and management (Nerves 3, 4, 6)

A.A. Patients under 50Patients under 50

•• MRI/MRAMRI/MRA

•• Blood tests (FBS, ANA, RPR, Lyme titer, ESR)Blood tests (FBS, ANA, RPR, Lyme titer, ESR)

•• Lumbar punctureLumbar puncture

B.B. Patients over 50Patients over 50

•• Atherosclerosis evaluationAtherosclerosis evaluation

•• ESR, CRP, platelets for temporal arteritisESR, CRP, platelets for temporal arteritis

•• Consider MRI/MRAConsider MRI/MRA

C.C. Don’t forgetDon’t forget•• Myasthenia gravisMyasthenia gravis

•• Thyroid ophthalmopathyThyroid ophthalmopathy

CranialCranial Nerve 6 Nerve 6 –– AbducensAbducens NerveNerveCranialCranial Nerve 6 Nerve 6 –– AbducensAbducens NerveNerve

•• 78 78 y.oy.o. WF: acute horizontal . WF: acute horizontal diplopiadiplopia

•• Vague Vague HxHx of episode of of episode of amaurosisamaurosis fugaxfugax

•• Generalized weakness, unintentional weight lossGeneralized weakness, unintentional weight loss

•• New onset diffuse headacheNew onset diffuse headache

•• Well controlled hypertensionWell controlled hypertension

•• VA: 20/20 RT/LTVA: 20/20 RT/LT

•• Pupils normal, no RAPDPupils normal, no RAPD

•• Motility Motility –– RT lateral rectus palsyRT lateral rectus palsy

•• 78 78 y.oy.o. WF: acute horizontal . WF: acute horizontal diplopiadiplopia

•• Vague Vague HxHx of episode of of episode of amaurosisamaurosis fugaxfugax

•• Generalized weakness, unintentional weight lossGeneralized weakness, unintentional weight loss

•• New onset diffuse headacheNew onset diffuse headache

•• Well controlled hypertensionWell controlled hypertension

•• VA: 20/20 RT/LTVA: 20/20 RT/LT

•• Pupils normal, no RAPDPupils normal, no RAPD

•• Motility Motility –– RT lateral rectus palsyRT lateral rectus palsy

Cranial Nerve 6 Cranial Nerve 6 –– AbducensAbducens NerveNerveCranial Nerve 6 Cranial Nerve 6 –– AbducensAbducens NerveNerve•• CBC CBC –– mild anemia 11.6 (14gms/mild anemia 11.6 (14gms/dLdL))

•• ESR ESR –– 61mm/hr ( 61mm/hr ( [age+10[age+10] = ] = 78+1078+10 = = 8888 = 44)= 44)22 2 2 22

•• CRP CRP –– 8mg/8mg/dLdL (<2.45)(<2.45)

•• Platelets Platelets –– 450,000 (150450,000 (150--450)450)

•• Temporal artery biopsy Temporal artery biopsy -- positivepositive

•• CBC CBC –– mild anemia 11.6 (14gms/mild anemia 11.6 (14gms/dLdL))

•• ESR ESR –– 61mm/hr ( 61mm/hr ( [age+10[age+10] = ] = 78+1078+10 = = 8888 = 44)= 44)22 2 2 22

•• CRP CRP –– 8mg/8mg/dLdL (<2.45)(<2.45)

•• Platelets Platelets –– 450,000 (150450,000 (150--450)450)

•• Temporal artery biopsy Temporal artery biopsy -- positivepositive

Cranial Nerve 7 Cranial Nerve 7 –– Facial NerveFacial NerveCranial Nerve 7 Cranial Nerve 7 –– Facial NerveFacial Nerve

•• Sensory Sensory –– taste to anterior 2/3 tonguetaste to anterior 2/3 tongue

•• Motor Motor –– muscles of facial expressionmuscles of facial expression

•• Sensory Sensory –– taste to anterior 2/3 tonguetaste to anterior 2/3 tongue

•• Motor Motor –– muscles of facial expressionmuscles of facial expression

Stroke vs. Bell’s PalsyStroke vs. Bell’s PalsyStroke vs. Bell’s PalsyStroke vs. Bell’s Palsy

•• Upper motor neuron lesionUpper motor neuron lesion

•• Contralateral loss of lower muscle functionContralateral loss of lower muscle function

•• Spares the foreheadSpares the forehead

•• Upper motor neuron lesionUpper motor neuron lesion

•• Contralateral loss of lower muscle functionContralateral loss of lower muscle function

•• Spares the foreheadSpares the forehead

Bell’s Palsy vs. StrokeBell’s Palsy vs. StrokeBell’s Palsy vs. StrokeBell’s Palsy vs. Stroke

•• Lower motor neuron lesionLower motor neuron lesion

•• Affects one entire side of faceAffects one entire side of face

•• Ipsilateral to the lesion Ipsilateral to the lesion

•• Lower motor neuron lesionLower motor neuron lesion

•• Affects one entire side of faceAffects one entire side of face

•• Ipsilateral to the lesion Ipsilateral to the lesion

Cranial Nerve 8 Cranial Nerve 8 –– Acoustic NerveAcoustic NerveCranial Nerve 8 Cranial Nerve 8 –– Acoustic NerveAcoustic Nerve

•• Auditory acuityAuditory acuity

•• SensorineuralSensorineural vsvs conduction deafnessconduction deafness

•• Weber test Weber test –– lateralizationlateralization

•• RinneRinne test test –– compare air and bone conductioncompare air and bone conduction

•• Auditory acuityAuditory acuity

•• SensorineuralSensorineural vsvs conduction deafnessconduction deafness

•• Weber test Weber test –– lateralizationlateralization

•• RinneRinne test test –– compare air and bone conductioncompare air and bone conduction

Cranial Nerve 8 Cranial Nerve 8 –– Acoustic NerveAcoustic NerveCranial Nerve 8 Cranial Nerve 8 –– Acoustic NerveAcoustic Nerve

•• All sensory no motor functionAll sensory no motor function

•• Weber Test Weber Test –– tuning fork: vertex of headtuning fork: vertex of head

-- if normal, equal both sidesif normal, equal both sides

-- neurosensoryneurosensory loss, best in normal earloss, best in normal ear

-- conduction loss, best in abnormal earconduction loss, best in abnormal ear

•• RinneRinne Test Test -- tuning fork: mastoid processtuning fork: mastoid process

-- normally, air transmission greater than normally, air transmission greater than bone conductionbone conduction

-- neurosensoryneurosensory loss, air greater than boneloss, air greater than bone

-- conduction loss, bone greater than airconduction loss, bone greater than air

•• All sensory no motor functionAll sensory no motor function

•• Weber Test Weber Test –– tuning fork: vertex of headtuning fork: vertex of head

-- if normal, equal both sidesif normal, equal both sides

-- neurosensoryneurosensory loss, best in normal earloss, best in normal ear

-- conduction loss, best in abnormal earconduction loss, best in abnormal ear

•• RinneRinne Test Test -- tuning fork: mastoid processtuning fork: mastoid process

-- normally, air transmission greater than normally, air transmission greater than bone conductionbone conduction

-- neurosensoryneurosensory loss, air greater than boneloss, air greater than bone

-- conduction loss, bone greater than airconduction loss, bone greater than air

Cranial Nerves 7 and 8Cranial Nerves 7 and 8Cranial Nerves 7 and 8Cranial Nerves 7 and 8

•• 85 85 y.oy.o. WF: recent onset facial muscle spasms. WF: recent onset facial muscle spasms

•• Periodic RT lid closing, elevation RT side of mouthPeriodic RT lid closing, elevation RT side of mouth

•• Started 3 months ago, occurs 1Started 3 months ago, occurs 1--5 times daily5 times daily

•• RT ear feels full of waterRT ear feels full of water

•• Past history of vertigo, RT sided hearing lossPast history of vertigo, RT sided hearing loss

•• VA: 20/25 RT/LTVA: 20/25 RT/LT

•• Pupils normal, No RAPDPupils normal, No RAPD

•• No facial spasm seenNo facial spasm seen

•• 85 85 y.oy.o. WF: recent onset facial muscle spasms. WF: recent onset facial muscle spasms

•• Periodic RT lid closing, elevation RT side of mouthPeriodic RT lid closing, elevation RT side of mouth

•• Started 3 months ago, occurs 1Started 3 months ago, occurs 1--5 times daily5 times daily

•• RT ear feels full of waterRT ear feels full of water

•• Past history of vertigo, RT sided hearing lossPast history of vertigo, RT sided hearing loss

•• VA: 20/25 RT/LTVA: 20/25 RT/LT

•• Pupils normal, No RAPDPupils normal, No RAPD

•• No facial spasm seenNo facial spasm seen

Cranial Nerve 7 Cranial Nerve 7 –– Facial NerveFacial NerveCranial Nerve 7 Cranial Nerve 7 –– Facial NerveFacial Nerve

•• Benign essential Benign essential blepharospasmblepharospasm

-- bilateral contractions of bilateral contractions of orbicularisorbicularis oculioculi, ,

procerusprocerus and and corrugatorcorrugator

-- idiopathic, benign, 50idiopathic, benign, 50--70 years old70 years old

•• MeigeMeige syndromesyndrome

-- BEB plus BEB plus orofacialorofacial muscle contractionmuscle contraction

•• Benign essential Benign essential blepharospasmblepharospasm

-- bilateral contractions of bilateral contractions of orbicularisorbicularis oculioculi, ,

procerusprocerus and and corrugatorcorrugator

-- idiopathic, benign, 50idiopathic, benign, 50--70 years old70 years old

•• MeigeMeige syndromesyndrome

-- BEB plus BEB plus orofacialorofacial muscle contractionmuscle contraction

Cranial Nerve 7 Cranial Nerve 7 –– Facial NerveFacial Nerve(cont.)(cont.)

Cranial Nerve 7 Cranial Nerve 7 –– Facial NerveFacial Nerve(cont.)(cont.)

•• HemifacialHemifacial spasmspasm

-- unilateral, intermittent facial muscle contractionsunilateral, intermittent facial muscle contractions

-- idiopathic, artery compressing 7idiopathic, artery compressing 7thth CN, aneurysm, CN, aneurysm, multiple sclerosis, multiple sclerosis, arteriovenousarteriovenous malformation, malformation,

brainstem or brainstem or cerebellopontinecerebellopontine angle tumorangle tumor

-- MRI to rule out brain pathologyMRI to rule out brain pathology

•• HemifacialHemifacial spasmspasm

-- unilateral, intermittent facial muscle contractionsunilateral, intermittent facial muscle contractions

-- idiopathic, artery compressing 7idiopathic, artery compressing 7thth CN, aneurysm, CN, aneurysm, multiple sclerosis, multiple sclerosis, arteriovenousarteriovenous malformation, malformation,

brainstem or brainstem or cerebellopontinecerebellopontine angle tumorangle tumor

-- MRI to rule out brain pathologyMRI to rule out brain pathology


•• MRI MRI –– 4x9 mm enhancing mass of RT internal auditory 4x9 mm enhancing mass of RT internal auditory canal extending into RT canal extending into RT cerebellopontinecerebellopontine angle angle impinging Cranial Nerves 7 and 8impinging Cranial Nerves 7 and 8

•• MRI MRI –– 4x9 mm enhancing mass of RT internal auditory 4x9 mm enhancing mass of RT internal auditory canal extending into RT canal extending into RT cerebellopontinecerebellopontine angle angle impinging Cranial Nerves 7 and 8impinging Cranial Nerves 7 and 8


•• Audiogram Audiogram –– confirmed confirmed sensorineuralsensorineural hearing losshearing loss

•• Vestibular Vestibular schwannomaschwannoma (acoustic (acoustic neuromaneuroma))

•• Benign, 80% of Benign, 80% of cerebellopontinecerebellopontine angle tumorsangle tumors

•• Surgery, radiation, Surgery, radiation, botulinumbotulinum toxin for facial spasmstoxin for facial spasms

•• Audiogram Audiogram –– confirmed confirmed sensorineuralsensorineural hearing losshearing loss

•• Vestibular Vestibular schwannomaschwannoma (acoustic (acoustic neuromaneuroma))

•• Benign, 80% of Benign, 80% of cerebellopontinecerebellopontine angle tumorsangle tumors

•• Surgery, radiation, Surgery, radiation, botulinumbotulinum toxin for facial spasmstoxin for facial spasms

Cranial Nerve 9 Cranial Nerve 9 –– GlossopharyngealGlossopharyngeal NerveNerveCranial Nerve 9 Cranial Nerve 9 –– GlossopharyngealGlossopharyngeal NerveNerve

•• Has sensory and motor fibersHas sensory and motor fibers

•• Innervates pharynx, posterior 1/3 tongueInnervates pharynx, posterior 1/3 tongue

•• Gag reflex tests both CN 9 and CN 10 Gag reflex tests both CN 9 and CN 10 –– VagusVagus

•• Uvula deviates to unaffected sideUvula deviates to unaffected side

•• Has sensory and motor fibersHas sensory and motor fibers

•• Innervates pharynx, posterior 1/3 tongueInnervates pharynx, posterior 1/3 tongue

•• Gag reflex tests both CN 9 and CN 10 Gag reflex tests both CN 9 and CN 10 –– VagusVagus

•• Uvula deviates to unaffected sideUvula deviates to unaffected side

Cranial Nerve 9 Cranial Nerve 9 –– GlossopharyngealGlossopharyngeal NerveNerveCranial Nerve 9 Cranial Nerve 9 –– GlossopharyngealGlossopharyngeal NerveNerve Cranial Nerve 11 Cranial Nerve 11 –– Accessory NerveAccessory NerveCranial Nerve 11 Cranial Nerve 11 –– Accessory NerveAccessory Nerve

•• Motor Motor –– elevation and upward rotation of scapulaelevation and upward rotation of scapula

•• TrapeziusTrapezius –– shoulder shrugshoulder shrug

•• Motor Motor –– elevation and upward rotation of scapulaelevation and upward rotation of scapula

•• TrapeziusTrapezius –– shoulder shrugshoulder shrug

Cranial Nerve 11 Cranial Nerve 11 –– Accessory NerveAccessory NerveCranial Nerve 11 Cranial Nerve 11 –– Accessory NerveAccessory Nerve

•• Motor Motor –– tilts face and elevates chin to opposite sidetilts face and elevates chin to opposite side

•• SternocleidomastoidSternocleidomastoid –– palpate against resistancepalpate against resistance

•• Motor Motor –– tilts face and elevates chin to opposite sidetilts face and elevates chin to opposite side

•• SternocleidomastoidSternocleidomastoid –– palpate against resistancepalpate against resistance

Cranial Nerve 12 Cranial Nerve 12 –– Hypoglossal NerveHypoglossal NerveCranial Nerve 12 Cranial Nerve 12 –– Hypoglossal NerveHypoglossal Nerve

•• Motor Motor innervationinnervation to tongueto tongue

•• Tongue deviates to side of Tongue deviates to side of weaknessweakness

•• Motor Motor innervationinnervation to tongueto tongue

•• Tongue deviates to side of Tongue deviates to side of weaknessweakness

Cranial Nerve 12 Cranial Nerve 12 –– Hypoglossal NerveHypoglossal NerveCranial Nerve 12 Cranial Nerve 12 –– Hypoglossal NerveHypoglossal Nerve

•• Have patient stick out their tongueHave patient stick out their tongue-- normal: no deviationnormal: no deviation-- abnormal: tongue deviates toward lesionabnormal: tongue deviates toward lesion

•• Have patient stick out their tongueHave patient stick out their tongue-- normal: no deviationnormal: no deviation-- abnormal: tongue deviates toward lesionabnormal: tongue deviates toward lesion

Motor SystemMotor SystemMotor SystemMotor System

•• Gait: walk across roomGait: walk across room

•• CerebellarCerebellar Disease: walk heelDisease: walk heel--toto--toe toe (tandem gait)(tandem gait)

•• Romberg Test: patient stands with his feet Romberg Test: patient stands with his feet together and with eyes closed. Tests for together and with eyes closed. Tests for cerebellarcerebellar ataxia. If Argyllataxia. If Argyll--Robertson pupils Robertson pupils present consider present consider tabestabes dorsalisdorsalis –– syphilis.syphilis.

•• Gait: walk across roomGait: walk across room

•• CerebellarCerebellar Disease: walk heelDisease: walk heel--toto--toe toe (tandem gait)(tandem gait)

•• Romberg Test: patient stands with his feet Romberg Test: patient stands with his feet together and with eyes closed. Tests for together and with eyes closed. Tests for cerebellarcerebellar ataxia. If Argyllataxia. If Argyll--Robertson pupils Robertson pupils present consider present consider tabestabes dorsalisdorsalis –– syphilis.syphilis.

Deep Tendon ReflexDeep Tendon ReflexDeep Tendon ReflexDeep Tendon Reflex

•• Knee reflex: with patient sitting, briskly tap the Knee reflex: with patient sitting, briskly tap the patellar tendon just below the patellapatellar tendon just below the patella

•• Adie syndrome: tonic pupil & Adie syndrome: tonic pupil & diminished deep diminished deep tendon reflexestendon reflexes

•• Knee reflex: with patient sitting, briskly tap the Knee reflex: with patient sitting, briskly tap the patellar tendon just below the patellapatellar tendon just below the patella

•• Adie syndrome: tonic pupil & Adie syndrome: tonic pupil & diminished deep diminished deep tendon reflexestendon reflexes

Adie Tonic PupilAdie Tonic PupilAdie Tonic PupilAdie Tonic Pupil

•• PostPost--ganglionicganglionic denervationdenervation of iris sphincter and of iris sphincter and ciliaryciliary bodybody

•• No response to light, consensual absentNo response to light, consensual absent

•• Sluggish near response with slow Sluggish near response with slow redilationredilation

•• More neural fibers controlling near than More neural fibers controlling near than pupillarypupillaryreflexreflex

•• LightLight--near dissociationnear dissociation

•• PostPost--ganglionicganglionic denervationdenervation of iris sphincter and of iris sphincter and ciliaryciliary bodybody

•• No response to light, consensual absentNo response to light, consensual absent

•• Sluggish near response with slow Sluggish near response with slow redilationredilation

•• More neural fibers controlling near than More neural fibers controlling near than pupillarypupillaryreflexreflex

•• LightLight--near dissociationnear dissociation

Adie Tonic PupilAdie Tonic Pupil(cont.)(cont.)

Adie Tonic PupilAdie Tonic Pupil(cont.)(cont.)

•• Vermiform pupil response Vermiform pupil response –– segmental constriction, segmental constriction, sectoralsectoral iris sphincter palsyiris sphincter palsy

•• Young women, 80% Young women, 80% -- 90% unilateral, bilateral 4%/year90% unilateral, bilateral 4%/year

•• Affected pupil slowly constricts over time becoming Affected pupil slowly constricts over time becoming smaller than unaffected pupilsmaller than unaffected pupil

•• Etiology Etiology –– idiopathic, trauma, viral affects idiopathic, trauma, viral affects ciliaryciliaryganglionganglion

•• DenervationDenervation hypersensitivity hypersensitivity –– 1/8% 1/8% pilocarpinepilocarpine ––constricts Adie pupilconstricts Adie pupil

•• Vermiform pupil response Vermiform pupil response –– segmental constriction, segmental constriction, sectoralsectoral iris sphincter palsyiris sphincter palsy

•• Young women, 80% Young women, 80% -- 90% unilateral, bilateral 4%/year90% unilateral, bilateral 4%/year

•• Affected pupil slowly constricts over time becoming Affected pupil slowly constricts over time becoming smaller than unaffected pupilsmaller than unaffected pupil

•• Etiology Etiology –– idiopathic, trauma, viral affects idiopathic, trauma, viral affects ciliaryciliaryganglionganglion

•• DenervationDenervation hypersensitivity hypersensitivity –– 1/8% 1/8% pilocarpinepilocarpine ––constricts Adie pupilconstricts Adie pupil

Thank You and QuestionsThank You and QuestionsThank You and QuestionsThank You and Questions

Documents

The Cranial Nerve Connection