In working up vertigo, use the HINTS exam to help differentiate benign (peripheral) from worrisome (central) causes.  If the patient has sustained and prolonged vertigo over hours to days, and/or has spontaneous nystagmus on visual inspection, in the setting of an otherwise normal neurological exam, proceed with the HINTS exam.  The HINTS exam utilizes the Head Impulse test (HI), Nystagmus test (NT), and the test of Skew (S).  If the head impulse test is positive (with catchup saccade), the patient likely has a benign etiology such as vestibular neuritis, coupled with an otherwise normal neurologic exam.   If the head impulse test is normal, a cerebellar stroke or other central etiology such as brain stem cva, vertebrobasilar TIA, MS, etc, is still not ruled out.  In testing for nystagmus, If the nystagmus is unidirectional, the vertigo is likely benign.  If the vertigo is bidirectional or vertical, the etiology is likely central.  If the test of skew is abnormal, it suggests a central etiology of vertigo.  If the patient has a negative Head Impulse test, bidirectional or vertical nystagmus, and and/or a positive test of Skew, a stat MRI is indicated.  If the patient has vertigo that is not sustained, with no spontaneous nystagmus on visual inspection, and vertigo is related to head movement, especially turning over in bed, proceed with the Dix-Hallpike maneuver to assess for benign paroxysmal positional vertigo(bppv).