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NEURO NEURO OPHTHALMOLOGYOPHTHALMOLOGY
Dr Geeta Lal Dr Geeta Lal
RCSIRCSI
NEURO OPHTHALMOLOGYNEURO OPHTHALMOLOGY
Topics covered in this lecture are:Topics covered in this lecture are:Pupillary disordersPupillary disordersNeuro motility disordersNeuro motility disordersOptic nerve diseaseOptic nerve diseaseVisual field defectsVisual field defects
PUPILLARY PATHWAYSPUPILLARY PATHWAYS
Anatomy and physiologyAnatomy and physiology The iris controls the size of the pupil. It contains The iris controls the size of the pupil. It contains
two groups of smooth muscle fibres:two groups of smooth muscle fibres: Sphincter pupillae innervated by the parasympathetic Sphincter pupillae innervated by the parasympathetic
nervous systemnervous system Dilator pupillae innervated by the sympathetic Dilator pupillae innervated by the sympathetic
nervous system nervous system
Pupil size (normal 2-6 mm) depends on the Pupil size (normal 2-6 mm) depends on the balance between sympathetic and balance between sympathetic and parasympathetic toneparasympathetic tone
PUPILLARY DISORDERSPUPILLARY DISORDERS
AnisocoriaAnisocoria = unequal pupils= unequal pupils A 1-2mm difference in pupil size can be physiologicalA 1-2mm difference in pupil size can be physiological Check in bright and dark room to ascertain which pupil is Check in bright and dark room to ascertain which pupil is
abnormalabnormal If one pupil is abnormally constricted the anisocoria will increase If one pupil is abnormally constricted the anisocoria will increase
when lights dimmedwhen lights dimmed If one pupil is abnormally dilated the anisocoria will decrease If one pupil is abnormally dilated the anisocoria will decrease
when lights dimmedwhen lights dimmed Physiological anisocoria will remain unchangedPhysiological anisocoria will remain unchanged
ANISOCORIAANISOCORIA
Dilated pupil
MydriasisMydriasis
= dilated pupil= dilated pupilCausesCauses
33rdrd nerve palsy nerve palsyAdies pupilAdies pupilPharmacologicalPharmacologicalTraumaTraumaAcute glaucomaAcute glaucoma
MiosisMiosis
= constricted pupil= constricted pupilCausesCauses
Horner’s syndromeHorner’s syndromePharmacologicalPharmacological Iris abnormalities (e.g. posterior synechiae) Iris abnormalities (e.g. posterior synechiae) Painful inflamed eye e.g. iritis, keratitisPainful inflamed eye e.g. iritis, keratitisArgyll Robertson pupilArgyll Robertson pupil
Horner’s syndromeHorner’s syndrome Lesion of the sympathetic pathway in head and Lesion of the sympathetic pathway in head and
neckneck Miosis, ptosis and anhidrosisMiosis, ptosis and anhidrosis Myriad of causes including Pancoast apical lung Myriad of causes including Pancoast apical lung
tumourtumour DiagnosisDiagnosis
Cocaine drops dilate normal pupil but not Horner’s Cocaine drops dilate normal pupil but not Horner’s pupilpupil
Hydroxyamphetamine drops locate the lesion as pre-Hydroxyamphetamine drops locate the lesion as pre-ganglionic (dilates pupil) or post-ganglionic (does not ganglionic (dilates pupil) or post-ganglionic (does not dilate)dilate)
Further investigations directed by history and examFurther investigations directed by history and exam
Relative afferent pupillary defectRelative afferent pupillary defect
Caused by optic nerve lesion or severe Caused by optic nerve lesion or severe retinal damage, i.e. a lesion anterior to retinal damage, i.e. a lesion anterior to optic chiasmoptic chiasm
Can be elicited by SWINGING FLASH Can be elicited by SWINGING FLASH LIGHT TESTLIGHT TEST If the light source is “swung” from eye to eye, If the light source is “swung” from eye to eye,
dwelling 2-3 secs on each, the affected pupil dwelling 2-3 secs on each, the affected pupil will paradoxically dilatewill paradoxically dilate
Adies pupilAdies pupil
Unilateral dilated pupilUnilateral dilated pupil Benign condition usually affecting young womenBenign condition usually affecting young women Onset is acute and may cause blurringOnset is acute and may cause blurring Absent light response; response to Absent light response; response to
accomodation slow but present = light near accomodation slow but present = light near dissociationdissociation
If associated with reduced or absent limb If associated with reduced or absent limb reflexes = Holmes Aides syndromereflexes = Holmes Aides syndrome
No known causeNo known cause
Pharmacological anisocoriaPharmacological anisocoria
Miosed pupilMiosed pupil PilocarpinePilocarpine OpiatesOpiates
Dilated pupilDilated pupil Atropine (systemic or eye drop)Atropine (systemic or eye drop) CyclopentolateCyclopentolate tropicamidetropicamide
Argyll Robertson pupilArgyll Robertson pupil
Pupils irregular, small and difficult to dilate with Pupils irregular, small and difficult to dilate with dropsdrops
Seen in neurosyphilisSeen in neurosyphilis Light near dissociation present Light near dissociation present
Near response present, light response absentNear response present, light response absent
NEUROMOTILITY DISORDESNEUROMOTILITY DISORDES
Related anatomy and physiologyRelated anatomy and physiology Six muscles control eye movements:Six muscles control eye movements: 1. Superior rectus1. Superior rectus 2. Medial rectus2. Medial rectus 3. Inferior rectus3. Inferior rectus 4. Inferior oblique4. Inferior oblique
(All the above muscles innervated by the 3(All the above muscles innervated by the 3rdrd nerve) nerve) 5. Superior oblique - innervated by 45. Superior oblique - innervated by 4thth nerve nerve 6. Lateral rectus - innervated by the 66. Lateral rectus - innervated by the 6thth nerve nerve The oblique muscles move the eye up (Inferior oblique) or down (superior The oblique muscles move the eye up (Inferior oblique) or down (superior
oblique) when it is turned inoblique) when it is turned in The superior and inferior recti move the eye up (SR) and down (IR)The superior and inferior recti move the eye up (SR) and down (IR) The lateral and medial recti abduct (move out) and adduct (move in) the eye The lateral and medial recti abduct (move out) and adduct (move in) the eye
respectivelyrespectively Eye movements are examined in the six different directions of gaze Eye movements are examined in the six different directions of gaze
representing individual muscle actionrepresenting individual muscle action
Third nerve palsyThird nerve palsy
Clinical features:Clinical features: Ptosis Ptosis Eye down and out Eye down and out Limited elevation, adduction and depressionLimited elevation, adduction and depression Pupil sparing or pupil involving (pupil fixed and Pupil sparing or pupil involving (pupil fixed and
dilated) dilated)
Pupil involving third nerve palsy = PCA Pupil involving third nerve palsy = PCA aneurysm until proven otherwise. Life aneurysm until proven otherwise. Life threatening neurosurgical emergencythreatening neurosurgical emergency
Third nerve palsyThird nerve palsy
CausesCauses
- Idiopathic - Idiopathic
- Microvascular disease (diabetes, - Microvascular disease (diabetes, hypertension) hypertension)
- Posterior communicating artery aneurysm- Posterior communicating artery aneurysm
- Head trauma - Head trauma
- Tumours- Tumours
SIXTH NERVE PALSYSIXTH NERVE PALSY
Clinical featuresClinical features Esotropia (convergent squint) in the primary Esotropia (convergent squint) in the primary
position, due to unopposed action of the medial position, due to unopposed action of the medial rectus musclerectus muscle
Marked limitation of abductionMarked limitation of abduction Horizontal diplopia (double vision)Horizontal diplopia (double vision)
SIXTH NERVE PALSYSIXTH NERVE PALSY
CausesCauses Microvascular disease (diabetes, hypertension)Microvascular disease (diabetes, hypertension) Raised intracranial pressure Raised intracranial pressure Acoustic neuroma (cerebellopontine angle Acoustic neuroma (cerebellopontine angle
tumour)tumour) Nasopharyngeal tumours Nasopharyngeal tumours Trauma (basal skull fracture)Trauma (basal skull fracture)
FOURTH NERVE PALSYFOURTH NERVE PALSY
Clinical features:Clinical features: Affected eye is hypertropic, i.e. at higher position Affected eye is hypertropic, i.e. at higher position
than the unaffected eyethan the unaffected eye Hypertropia increases on tilting the head to the Hypertropia increases on tilting the head to the
ipsilateral shoulder ipsilateral shoulder Vertical diplopiaVertical diplopia Patient adopts a compensatory head tilt to the Patient adopts a compensatory head tilt to the
opposite side to prevent diplopiaopposite side to prevent diplopia
FOURTH NERVE PALSYFOURTH NERVE PALSY
Causes:Causes: Congenital – may not develop until adult lifeCongenital – may not develop until adult life AcquiredAcquired
TraumaTrauma Microvascular diseaseMicrovascular disease Aneurysms and tumours rareAneurysms and tumours rare
Myasthenia gravisMyasthenia gravis
Autoimmune disorder of the Autoimmune disorder of the neuromuscular junctionneuromuscular junction
Systemic and ocular featuresSystemic and ocular featuresPtosis, ophthalmoloplegia and weak Ptosis, ophthalmoloplegia and weak
orbicularis muscleorbicularis muscleFatigable, asymmetrical, variableFatigable, asymmetrical, variable
Tensilon test confirms diagnosisTensilon test confirms diagnosis
OPTIC NERVE DISEASE (OPTIC OPTIC NERVE DISEASE (OPTIC NEUROPATHY)NEUROPATHY)
CONGENITALCONGENITAL ACQUIREDACQUIRED
Inflammatory (optic neuritis) Inflammatory (optic neuritis) Vascular (ischaemic) optic neuropathyVascular (ischaemic) optic neuropathy
Arteritic (Giant cell arteritis) or Non arteriticArteritic (Giant cell arteritis) or Non arteritic Compressive optic neuropathy (tumours)Compressive optic neuropathy (tumours) Infiltrative/granulomatous optic neuropathy (Sarcoidosis, Leukemia )Infiltrative/granulomatous optic neuropathy (Sarcoidosis, Leukemia ) TraumaTrauma Toxic optic neuropathy, e.g. methyl alcoholToxic optic neuropathy, e.g. methyl alcohol Nutritional, e.g. vitamin B12 deficiencyNutritional, e.g. vitamin B12 deficiency Drug induced, e.g. EthambutolDrug induced, e.g. Ethambutol Radiation optic neuropathy Radiation optic neuropathy Hereditary optic neuropathy (Lebers)Hereditary optic neuropathy (Lebers)
OPTIC NERVE DISEASEOPTIC NERVE DISEASE
Clinical signsClinical signs Reduced visual acuityReduced visual acuity Relative afferent pupillary defectRelative afferent pupillary defect Abnormal colour visionAbnormal colour vision
Red desaturationRed desaturation
Visual field defectVisual field defect
OPTIC NEURITISOPTIC NEURITIS
Inflammatory optic neuropathy commonly due to Inflammatory optic neuropathy commonly due to demyelination (i.e. multiple sclerosis)demyelination (i.e. multiple sclerosis)
Symptoms Symptoms - Sudden loss of vision with recovery over 6-12 weeks- Sudden loss of vision with recovery over 6-12 weeks - Painful eye movements- Painful eye movements
SignsSigns - Reduced visual acuity- Reduced visual acuity - Impaired colour vision - Impaired colour vision - RAPD- RAPD - Visual field defect – variable- Visual field defect – variable - Optic disc may be normal or swollen- Optic disc may be normal or swollen - Visually evoked responses show increased latency- Visually evoked responses show increased latency
OPTIC NEURITISOPTIC NEURITIS
Swollen disc
ANTERIOR ISCHAEMIC OPTIC ANTERIOR ISCHAEMIC OPTIC NEUROPATHYNEUROPATHY
1. Arteritic1. ArteriticGiant cell arteritis causes occlusion of Giant cell arteritis causes occlusion of
posterior ciliary arteries of optic nerveposterior ciliary arteries of optic nerveUntreated can cause sudden bilateral Untreated can cause sudden bilateral
blindnessblindnessNever miss this diagnosisNever miss this diagnosis
2. Non-arteritic2. Non-arteritic
Giant cell arteritisGiant cell arteritis
Occlusive vasculitis of ophthalmic artery and its branchesOcclusive vasculitis of ophthalmic artery and its branches ElderlyElderly SymptomsSymptoms
Bilateral irreversible visual loss if untreatedBilateral irreversible visual loss if untreated Temporal tendernessTemporal tenderness Jaw claudicationJaw claudication Scalp tendernessScalp tenderness HeadacheHeadache Constitutional symptoms, eg weight loss, anorexiaConstitutional symptoms, eg weight loss, anorexia
SignsSigns Variable visual acuity but often severe vision lossVariable visual acuity but often severe vision loss Pale optic disc with diffuse edema and haemorrhagesPale optic disc with diffuse edema and haemorrhages later optic atrophylater optic atrophy Thickened non pulsatile temporal arteryThickened non pulsatile temporal artery
Giant cell arteritisGiant cell arteritis
Investigations (urgent)Investigations (urgent) ESR raised > 60 mm/hr (normal = half the age for men ESR raised > 60 mm/hr (normal = half the age for men
and half the age plus 10 for women)and half the age plus 10 for women) C reactive protein (CRP) raisedC reactive protein (CRP) raised Temporal artery biopsy - histology confirms diagnosisTemporal artery biopsy - histology confirms diagnosis
TreatmentTreatment Aim is to prevent blindness in the fellow eyeAim is to prevent blindness in the fellow eye Initial treatment is with high dose intravenous Initial treatment is with high dose intravenous
methylprednisolone then oral prednisolone 60 mg methylprednisolone then oral prednisolone 60 mg daily.Taper oral steroids graduallydaily.Taper oral steroids gradually
Non arteritic anterior ischaemic Non arteritic anterior ischaemic anterior optic neuropathyanterior optic neuropathy
Clinical featuresClinical features - Age group affected usually is 45-65 yrs- Age group affected usually is 45-65 yrs - Altitudinal visual field defect- Altitudinal visual field defect - Visual loss of variable degree- Visual loss of variable degree - Swollen optic disc with edema /splinter haemorrhages- Swollen optic disc with edema /splinter haemorrhages - Normal ESR and CRP- Normal ESR and CRP - Hypertension - Hypertension
TreatmentTreatment- Treat underlying vascular disorders (Hypertension , Treat underlying vascular disorders (Hypertension ,
Diabetes,Hyperlipidemia )Diabetes,Hyperlipidemia )- Aspirin to prevent further vascular eventsAspirin to prevent further vascular events
PapilloedemaPapilloedema
Bilateral optic disc swelling due to Bilateral optic disc swelling due to raised intracranial pressureraised intracranial pressure
Clinical featuresClinical features - Visual acuity usually normal- Visual acuity usually normal - May be associated with transient visual loss- May be associated with transient visual loss - Enlargement of the blind spot - Enlargement of the blind spot - Swollen discs- Swollen discs - Optic atrophy if chronic- Optic atrophy if chronic
Acute papilloedemaAcute papilloedema
s
Flame shaped haemorrhages
Cotton wool spots
Engorged retinal veins
Chronic papilloedemaChronic papilloedema
Pale waxy disc
PAPILLOEDEMAPAPILLOEDEMA
CausesCauses -Intracranial space occupying lesions, e.g. tumour, -Intracranial space occupying lesions, e.g. tumour,
HaemotomaHaemotoma -Any lesion causing hydrocephalus in adults e.g.. -Any lesion causing hydrocephalus in adults e.g..
Meningitis and subarachnoid haemorrhageMeningitis and subarachnoid haemorrhage - Venous obstruction caused by thrombosis in the venous - Venous obstruction caused by thrombosis in the venous
sinusessinuses - Benign intra cranial hypertension- Benign intra cranial hypertension
Differential diagnosisDifferential diagnosis - Malignant hypertension (always check blood pressure)- Malignant hypertension (always check blood pressure)
OPTIC NERVE DISEASEOPTIC NERVE DISEASE
Optic atrophyOptic atrophy
- Caused by damage to the nerve fibres at - Caused by damage to the nerve fibres at any point between the ganglion cells of any point between the ganglion cells of the retina and lateral geniculate bodythe retina and lateral geniculate body
- Irreversible loss of vision- Irreversible loss of vision
OPTIC ATROPHYOPTIC ATROPHY
ppa
Pale disc and thinned retinal vessels
OPTIC ATROPHYOPTIC ATROPHYCausesCauses 1. Retinal1. Retinal
Central retinal artery occlusionCentral retinal artery occlusionRetinitis pigmentosaRetinitis pigmentosa
2. Optic nerve2. Optic nerve Anterior Ischaemic optic neuropathyAnterior Ischaemic optic neuropathy Optic neuritisOptic neuritis Glaucoma Glaucoma Chronic papilloedemaChronic papilloedema Toxic e.g. Methyl alcohol, ethyl alcohol, tobacco and ethambutol.Toxic e.g. Methyl alcohol, ethyl alcohol, tobacco and ethambutol.
Tumour e.g. optic nerve glioma or meningiomaTumour e.g. optic nerve glioma or meningioma TraumaTrauma Leber’s Hereditary optic neuropathyLeber’s Hereditary optic neuropathy
3. Chiasm3. Chiasm Any cause of chiasmal compression e.g. pituitary adenoma, craniopharyngiomaAny cause of chiasmal compression e.g. pituitary adenoma, craniopharyngioma
VISUAL FIELD DEFECTSVISUAL FIELD DEFECTS Central scotomaCentral scotoma
Characteristic of most optic nerve lesions, e.g. optic neuritisCharacteristic of most optic nerve lesions, e.g. optic neuritis
Arcuate scotomaArcuate scotoma The scotoma extends from the blind spot above or below fixation The scotoma extends from the blind spot above or below fixation
following the course of nerve fibres. Characteristically seen in glaucoma.following the course of nerve fibres. Characteristically seen in glaucoma.
Bitemporal hemianopiaBitemporal hemianopia Loss of temporal half of the visual field bilaterally. Seen in chiasmal Loss of temporal half of the visual field bilaterally. Seen in chiasmal
compression by tumours, e.g. pituitary adenomacompression by tumours, e.g. pituitary adenoma
Homonymous hemianopiaHomonymous hemianopia Any visual pathway lesion posterior to the optic chiasm, e.g. stroke, Any visual pathway lesion posterior to the optic chiasm, e.g. stroke,
tumourtumour
VISUAL FIELD DEFECTSVISUAL FIELD DEFECTS
Left homonomous hemianopia
Bitemporal hemianopia
Monocular blindness
Monocular constricted field e.g. retinitis pigmentosa
Right nasal field defect, usually due to retinal disease or glaucoma