Fourth nerve palsy
Revision as of 10:50, 6 September 2015 by Neil.m.young (talk | contribs)
Background
- Trochlea innervates superior oblique muscle
- Intorts, depresses and abducts the globe
- Most common cause of vertical diplopia
- Vulnerable to head trauma [1]
- Practically never involved by aneurysm
- Herpes zoster opthalmicus can affect nerve
- Less commonly affected by diabetic infarction
- Palsies seen in lupus and Sjogren syndrome
- Unknown mechanism
Clinical Features
- Vertical diplopia[2]
- Worse on downward gaze and gaze away from affected muscle
- Head-tilt
- Tilt typically away from affected side
- May be easier to evaluate on old photos
Differential Diagnosis
Diagnostic Evaluation
- Rule out acute causes including CVA, trauma, herpes zoster
Management
- Address any acute causes
- May require surgical correction
Disposition
- Determined by etiology and clinical condition
See Also
External Links
http://emedicine.medscape.com/article/1200187-treatment