I was making some edits...thought I'd throw the reasons for those changes here, with my more aggressive thoughts for change only here for discussion:
1. Classification titles: the categories were incompletely described, as the article it references (Edlow Newman-Toker 2016) talks about Spontaneous episodic VS vs Triggered episodic VS vs Acute VS.
2. Central v Peripheral Table: firstly it's old and not the ideal way to approach these patients (Kattah et al "HINTS to diagnose stroke in AVS" Stroke 2009). Should use 'timing & triggers' method approach. Second hearing loss can be c/w an AICA stroke, so this should say variable/may occur ("Diagnosing stroke in acute vertigo: the HINTS family of eye movement tests and the future of the "eye ECG", Newman-Toker et al 2015, Seminal Neurology). And I'd say a stroke can be severe at onset so maybe change this too.
3. Imaging: I'd hazard CTA better than MRA for vessel imaging, wouldn't you?
4. Evaluation: Diagnostic algorithm: This algorithm is terrible in so many ways. Kattah 2009 as referenced in point #2 talks about patient description being inaccurate, so lead reader astray here. Then if you don't have CNS s/sx (does it consider HINTS in 'CNS' here?) then you move into only non-stroke causes. Also if hearing changes present it doesn't consider AICA stroke at all. Figure 2A of Edlow & Newman-Toker "Using the physical exam to diagnose patients with acute dizziness and vertigo" J Emerg Med 2016 I think would make a much more appropriate choice to replace this algorithm. First it forces the reader of this wikem page to know what "AVS" is. Second it forces them to preform the HIT, and if they cannot then it forces them to consider the worse stroke outcome. If used correctly it reduces the odds of stroke by '50-fold'.
- 1. Sits and stands independently
- 2. No cranial nerve or cerebellar signs
- 3. Unidirectional, horizontal nystagmus
- 4. Unilaterally abnormal head impulse
- 5. Normal vertical eye alignment (no skew)
5. HINTS Table: thought could be better defined. Should see 'corrective saccade' as abnormal finding, better to use the right term I think, and probably should say with which direction, e.g. "corrective saccade with HIT to the right" for better documentation. Then, never have I ever read that a lack of nystagmus is reassuring in an AVS patient. More likely I'd wonder if they are even suffering from AVS, if they have no current symptoms, if they received vestibular suppressive therapy already (e.g. valium) or if they have a peripheral cause with visual fixation causing suppression. I'd be more concerned with a lack of a reassuring unilat horiz nystag. And as to test of skew, maybe a little better said with lack of skew?
|HINTS Test||Reassuring Finding|
|Head Impulse Test||Abnormal (corrective saccade)|
|Test of Skew||No skew deviation|
7. Nystagmus Maybe better to say any other type of nystagmus is presumed abnormal (while there can be reassuring non-stroke causes (b/l peripheral lesions, therapeutic phenytoin level, alcohol intoxication, etc)
8. HINTS better than MRI: I think the reference for HINTS being more accurate than MRI should always carry the caveat that this is when the HINTS exam is preformed by neuro-opthalmologists. Maybe EM is just as good, and the article that give us hope is Vanni et al Emerg Med Australia 2015 "Can emergency physicians accurately and reliably assess acute vertigo in the emergency department?".