An Approach to the Patient with (Recent Onset) Spontaneous Episodic Vestibular Syndrome

𝗢𝗿𝗶𝗴𝗶𝗻𝗮𝗹 𝗗𝗲𝘀𝗰𝗿𝗶𝗽𝘁𝗶𝗼𝗻: A vascular etiology should always be on the differential diagnosis of the recent onset of the spontaneous (unprovoked) episodic vestibular syndrome (EVS), especially in the older population and when vascular risk factors are present. However, young patients can suffer from vascular events too - be especially concerned in patients with recent onset head/neck pain and vertigo. Unfortunately, the evaluation and management of this population is not one size fits all, but this flowchart offers a framework to the approach of the spontaneous EVS when the diagnosis is unknown and a vascular etiology is possible. First, are you seeing the patient in the midst of one of their typical attacks? If so and if spontaneous nystagmus is present during an episode (e.g., transient ischemic attack [TIA], Meniere's, vestibular migraine), the ‘HINTS Plus' exam can be applied (HIT=head impulse test; Bi/Vertical=bidirectional in lateral gaze or spontaneous vertical nystagmus; Uni=unidirectional nystagmus). However, seeing the pattern of a "peripheral" HINTS exam in the EVS is an uncommon situation and a comprehensive vestibular history and examination is necessary in this scenario (in addition to evaluating gait, stance, and coordination, cranial nerves, strength and sensation, and looking for peripheral (increased contralesional nystagmus) or central (reversal of horizontal nystagmus or "cross-coupling" where horizontal head-shaking causes vertical [usually downbeat] nystagmus) patterns of head-shaking-induced nystagmus. More often than not, the attack has subsided and the clinician is seeing the patient in the asymptomatic inter-ictal phase. Or, perhaps the patient is in the midst of an attack but there's no spontaneous nystagmus (e.g., ictally, there may or may not be nystagmus during a vestibular migraine attack). These two situations are common, and for each, the neurologic examination (especially evaluating gait, stance and coordination) and a thorough history are most important. Symptomatically, the presence of head motion intolerance, nausea and imbalance is suggestive of a vestibular etiology (although this by itself doesn't tell you whether you're dealing with a central disorder like a TIA, vestibular migraine, or a peripheral disorder like Meniere's) as compared to a non-vestibular etiology (e.g., cardiac arrhythmia, hypoglycemia). Be concerned by the Dangerous D's(1) or new sudden, sustained or severe head or neck pain (i.e., vertebral artery dissection until proven otherwise). If there are no clues in the neuro-vestibular history and examination, calculate the ABCD2 score next.(2, 3) While there is no specific benign/dangerous cut-off for this score, a score of 3-4 or more should be enough to initiate the TIA/stroke work-up expeditiously. However, a patient with a vestibular TIA can still have a score of 2 or less! Finally, don't forget about non-neurologic/non-vestibular etiologies, and be especially concerned by cardiorespiratory symptoms or transient loss of consciousness. A head CT scan is insufficient to evaluate for stroke unless there are focal findings on exam, a severe headache or change in mental status (e.g., posterior fossa hemorrhage), or if the patient is in a thrombolytic window. Brain MRI and MR angiogram head and neck (or MRI and CT angiogram) is preferable as the initial neuroimaging modality. 𝗡𝗲𝘂𝗿𝗼-𝗼𝗽𝗵𝘁𝗵𝗮𝗹𝗺𝗼𝗹𝗼𝗴𝘆 𝗮𝗻𝗱 𝗡𝗲𝘂𝗿𝗼-𝗼𝘁𝗼𝗹𝗼𝗴𝘆 𝗧𝗲𝘅𝘁𝗯𝗼𝗼𝗸 𝗟𝗲𝗴𝗲𝗻𝗱: A flowsheet approach to the patient with (recent onset) spontaneous episodic vestibular syndrome