Optic Disc Cupping
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Transcript of Optic Disc Cupping
NEURO-OPHTHALMOLOGY
Clinical Examination
• Visual Acuity• Colour Vision• Visual Fields• Pupils
Normal Eye and Optic Disc
Cupped disc
The swollen optic disc
•Papilloedema
•Papillitis
•Malignant hypertension
•Ischaemic optic neuropathy
•Diabetic optic neuropathy
•CRVO
•Intraocular inflammation
25 y.o. femaleReduced VAPain with eye movementColour desaturationRAPD
65 y.o. maleReduced VAPainless loss of visionEssential hypertensionSmoker
The pale optic disc •Congenital
•Secondary to
•raised ICP
•vascular retinal disease
•optic neuritis
•optic nerve compression
•trauma
•Glaucoma
Papilloedema• Disc swelling secondary to raised ICP• Headache
– Worse in the morning– Valsalva manouver
• Nausea and projectile vomiting• Horizontal diplopia (VI palsy)• Causes
– Space occupying lesion– Intracranial hypertension
• Idiopathic• Drugs • Endocrine
– Severe hypertension
Haemorrhages
CWS
Blurred optic disc margin
Small optic cup
Disc pallor
Vessel attenuation
Pupils
• First Order – Retina to Pretectal Nucleus in B/S (at level of Superior colliculus)• Second Order – Pretectal nucleus to E/W nucleus (bilateral innervation!)• Third Order – E/W nucleus to Ciliary Ganglion• Fourth Order – Ciliary Ganglion to Sphincter pupillae (via short ciliary nerves)
Pupil
• Constricted (mioisis)– Sympathetic
(pupillodilator) denervation
– Drugs• Pilocarpine• Morphine
• Dilated (mydriasis)– Parasympathetic
(pupilloconstrictor) denervation
– Lesion of the third CN– Drugs
• Atropine• Cocaine
Horner’s
• Oculosympathetic paresis
– Ptosis– Miosis– Ipsilateral anhidrosis– Does not dilate with
cocaine 4%
Sympathetic Pathway• First Order – Posterior Hypothalamus to Ciliospinal centre of Budge (C8-T2) (Uncrossed in Brainstem)• Second Order – Ciliospinal centre of Budge to Superior Cervical Ganaglion• Third Order – Superior Cervical Ganglion to dilator pupillae muscle. (Close to ICA and joins V1 intracranially)
Pancoast bronchogenic carcinoma
Otitis MediaTolosa-Hunt Sy.
CVATumour
Internal Carotid Dissection
Herpes Zoster
Causes of Horner’s pupil• Central – B/S lesions (tumours, vascular and MS) Syringomyelia, Lat. Med. Syn., S.C. ca.• Preganglionic – Pancoast tumour, Carotid & Aortic aneurysms, Neck lesions/trauma.• Postganglionic – Cluster headaches, Nasopharyngeal tumours, Otitis media, Cavernous sinus mass and ICA disease.• Miscellaneous – Congenital (brachial plexus injury) Idiopathic.
• Argyll-Robertson pupil– Small, irreg– Does not react to light – Reacts to
accommodation– Causes
• syphilis• diabetes
• Miotonic pupil (Adie’s syndrome)– Dilated– Poor response to light and
convergence.
• Constricts with weak Pilocarpine
• Holmes-Adie syndrome– Reduced tendon reflexes
(Knee, ankle)- Orthostatic hypotension
Afferent & efferent defects
Ocular motility abnormalities
• Third nerve palsy– Double vision– Eye turned down & out– Ptosis– Dilated pupil &
headache• Compressive lesion
• Sixth nerve palsy– Double vision – Eye turned in
Cranial Nerve PalsiesLooking straight ahead
Posterior communicating artery aneurysm
III CN
Posterior cerebral artery
Chiasma
Internuclear Ophthalmoplegia• Defective adduction of the
ipsilateral eye • Nystagmus of the contralateral
(abducting) eye • NORMAL CONVERGENCE• Causes
– Young patients• Bilateral • Demyelination
– Older patients• Unilateral• Vascular, tumours
Myasthenia Gravis
• Fatigability• Double vision• Lid twitch• Ptosis• Normal reflexes & sensation
INVESTIGATIONS MG
• Anti ACh receptor Ab’s• Electromyography• Tensilon test
– Edrophonium blocks acetyl-cholinesterase
– Beware of cholinergic cardiac effects. Use with Atropine 0.6mg
• Thoracic CT and MRI to rule out thymoma
Anti AChR Ab’s
AChR
ACh
Localising the lesion
• Monocular visual field defects indicate lesions anterior to the optic chiasm
• Bitemporal defects are the hallmark of chiasmal lesions
• Binocular homonymous hemianopia result from lesions in the contralateral postchiasmal region
• Binocular quadrantanopias reflect optic tract lesions