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The first 25 slides, exactly as they appear. The full deck has 55 content slides.
Ophthalmology
Electrodiagnostic Techniques in Neuro ophthalmology
Built from Khurana — Neuro-Ophthalmology
What’s inside
6 sections · 55 slides
Overview
- Why record electrical signals from the eye?
Visual-Evoked Potential (VEP)
Listening at the visual cortex
- VEP: what it actually is
- Why the VEP mostly reflects the central vision
- Two ways to stimulate the eye
- Getting the pattern stimulus right
- How the VEP is recorded
- Pattern-reversal VEP: right versus left eye
- Reading the waveform: the three things we measure
- Pattern VEP recording with a checkerboard stimulus
- Transient versus steady-state VEP
- What the VEP is used for
- Optic neuritis and MS: delayed conduction
- Prolonged-latency VEP in a demyelinating pattern
- Optic neuritis over time, and silent MS
- Cloudy eyes: seeing past a cataract
- Testing vision in babies who cannot tell us
- Sweep VEP: measuring acuity without words
- Tricky patients: motor disorders and nystagmus
- Non-organic (functional) visual loss
- Two more clues on the VEP
- Multifocal VEP: many fields at once
- What the multifocal VEP adds
Electroretinography (ERG)
Listening at the retina itself
- ERG: what it records
- Where the ERG waves come from
- How the ERG is recorded
- Rod, cone, and inner-retina responses
- Full-field flash ERG: the standard response set
- Describing the ERG waveform
- The flash ERG as a 'mass response'
- Pattern ERG (pERG): reading the ganglion cells
- Using the pERG to localise disease
- Photopic negative response (PhNR)
- Multifocal ERG (mfERG)
Electro-oculogram (EOG)
The eye as a battery
- EOG: the standing electrical battery of the eye
- Recording the EOG and the Arden ratio
- Electro-oculogram: saccade averages and the Arden ratio
- What the EOG is used for
Electromyography (EMG)
Listening at the muscle
- EMG and the fatigue signature of myasthenia
- Repetitive nerve stimulation of orbicularis oculi
- Single-fibre EMG, and telling muscle from nerve disease
Clinical scenarios
Choosing and reading the right test
- Is it the optic nerve or the macula?
- Is the visual loss real? (functional visual loss)
- Multifocal ERG topographic maps of the two eyes
- How good is the eye behind a cataract or haemorrhage?
- The big picture in three tests
- A patient recovered from optic neuritis now sees 6/6, yet the pattern VEP still shows a delayed P100. Why?
- References (1/2)
- References (2/2)
- Neuro-Ophthalmology