Acute Vertigo Evaluation (HINTS Exam)

Algorithm Steps

1. ▶

   Start

   Acute Continuous Vertigo

   Vertigo/dizziness with nystagmus, ongoing >24h

   1. ●

      Action

      Confirm Acute Vestibular Syndrome (AVS)

      Criteria for HINTS application

      • Acute onset vertigo/dizziness
      • Continuous symptoms (not episodic)
      • Nystagmus present on examination
      • Nausea/vomiting, gait unsteadiness
      • Duration >24 hours typical
      1. ●

         Action

         Not AVS

         HINTS not applicable

         • Episodic vertigo → consider BPPV, Meniere's
         • No nystagmus → different workup
         • Chronic dizziness → vestibular clinic
         • Light-headedness → orthostatic, cardiac
      2. ●

         Action

         Assess Stroke Risk Factors

         Higher index of suspicion if present

         • Age >50
         • Vascular risk factors (HTN, DM, smoking)
         • History of stroke/TIA
         • Atrial fibrillation
         • Neck pain (dissection risk)
         1. ●

            Action

            Perform HINTS Exam

            Head Impulse, Nystagmus, Test of Skew

            • Requires training for accuracy
            • Sensitivity >95% for stroke if done correctly
            • More sensitive than early MRI
            • Best within 48h of symptom onset
            1. ◆

               Decision

               Head Impulse Test (HIT)

               Assess VOR

               • Turn head rapidly, watch for catch-up saccade
               • POSITIVE (abnormal): catch-up saccade = peripheral
               • NEGATIVE (normal): no saccade = concerning for central
               1. ◆

                  Decision

                  HINTS Interpretation

                  Central or Peripheral?

                  • PERIPHERAL: Abnormal HIT + unidirectional nystagmus + no skew
                  • CENTRAL: ANY dangerous sign present
                  • Dangerous: Normal HIT, direction-changing nystagmus, or skew
                  1. ●

                     Action

                     HINTS Peripheral

                     Likely vestibular neuritis

                     • All 3 components reassuring
                     • Abnormal HIT (catch-up saccade)
                     • Unidirectional nystagmus
                     • No skew deviation
                     • Also check hearing (AIDP variant)
                     1. ●

                        Action

                        Check Hearing (Finger Rub)

                        HINTS-Plus

                        • New unilateral hearing loss suggests AICA stroke
                        • Even if HINTS peripheral, hearing loss = MRI
                        • AICA supplies inner ear and brainstem
                        1. ●

                           Action

                           Treat Vestibular Neuritis

                           Symptomatic management

                           • Vestibular suppressants short-term (meclizine, dimenhydrinate)
                           • Antiemetics PRN
                           • Early vestibular rehabilitation
                           • Steroids controversial (may help)
                           • Recovery over weeks
                           1. ✓

                              Outcome

                              Discharge with Follow-up

                              Peripheral vertigo care

                              • ENT or neurology follow-up
                              • Vestibular PT referral
                              • Return if new symptoms
                        2. ●

                           Action

                           MRI with DWI

                           Posterior fossa protocol

                           • MRI more sensitive than CT for posterior stroke
                           • DWI may be falsely negative in first 24-48h
                           • Consider repeat MRI if high clinical suspicion
                           • MRA to evaluate vertebrobasilar system
                           1. ●

                              Action

                              Stroke Workup/Treatment

                              Acute stroke protocol

                              • Neurology consult
                              • Consider tPA if within window
                              • Thrombectomy if LVO
                              • Admit to stroke unit
                              • Secondary prevention workup
                              1. ✓

                                 Outcome

                                 Admit for Stroke Care

                                 Inpatient management

                  2. ⚠

                     Warning

                     ⚠️ HINTS Central / Dangerous

                     Any one dangerous sign = stroke suspected

                     • Normal head impulse test
                     • Direction-changing nystagmus
                     • Skew deviation present
                     • Suspect posterior circulation stroke
                     • MRI urgently indicated
            2. ◆

               Decision

               Nystagmus Pattern

               Direction-changing or unidirectional?

               • UNIDIRECTIONAL: beats same direction = peripheral
               • DIRECTION-CHANGING: changes with gaze = central
               • Pure vertical/torsional = central
            3. ◆

               Decision

               Test of Skew

               Alternate cover test

               • Cover/uncover each eye
               • Watch for vertical correction
               • PRESENT (abnormal): vertical realignment = central
               • ABSENT (normal): no vertical misalignment = peripheral