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The first 25 slides, exactly as they appear. The full deck has 41 content slides.
Ophthalmology
Ocular Myasthenia Gravis
Built from Khurana — Neuro-Ophthalmology
What’s inside
7 sections · 41 slides
Overview
- What this topic covers
Understanding the Disease
What myasthenia is, and why the eye is so often the first target
- What is myasthenia gravis?
- Why the eye is the giveaway
- Ocular myasthenia by the numbers
- Who gets it: age, sex and race
Pathophysiology
Why an autoimmune attack on one junction makes muscles fatigue
- The core defect: a jammed nerve-muscle switch
- The neuromuscular junction and where myasthenia strikes
- How the antibodies do the damage
- Where does it come from? Three causes
- What makes it worse, and what it travels with
Clinical Features
The bedside picture: fatiguable lids and wandering eye movements
- General considerations: read the pattern, not one sign
- Ptosis: the commonest sign, and how to unmask it
- Two classic eyelid tricks: Cogan and the Peek sign
- Hering's law signs: one lid affects the other
- Fatiguable eyelid signs in ocular myasthenia
- Diplopia and disordered eye movements
- Variable ptosis and defective ocular motility
- The rest of the picture
Diagnosis
Proving a shifting disease: bedside tests, blood and electrodiagnostics
- How the diagnosis is approached
- The Tensilon (edrophonium) test
- Bedside tests when Tensilon is not ideal
- Improvement in ptosis after a diagnostic test
- Blood tests: antibodies and thyroid
- Imaging and electrodiagnostics
Treatment
Restoring strength, preventing generalisation, minimising drug harm
- Aims of treatment
- First-line drugs: anticholinesterases
- Immunosuppression: steroids and steroid-sparing drugs
- Newer and rescue therapies
- Surgery and supportive measures
Prognosis
A fluctuating disease that generally does well
- Outlook and course
- Key takeaways
- How would you confirm ocular myasthenia in a man with evening-worse ptosis, and why is one negative test not enough?
- References
- Neuro-Ophthalmology