Triggered by specific head movements (eg, Dix-Hallpike maneuver). Initial imaging. Brief episodic vertigo triggered by specific head movements (eg, Dix-Hallpike maneuver) is referred to as triggered episodic vestibular syndrome (t-EVS) and is most commonly due to BPPV; however, more ominous central causes may clinically mimic BPPV and are collectively referred to as CPPV [1]. BPPV results from mobile debris (canaliths) in the vestibular labyrinth. The diagnostic criteria for BPPV are clinical and well established [18-20]. Imaging evaluation in BPPV with typical nystagmus on Dix-Hallpike testing is unnecessary. In contrast, patients with CPPV present with symptoms of t-EVS but negative or atypical Dix-Hallpike testing are at an increased risk of having an acute central cause of vertigo identified on imaging [6]. Potential causes of CPPV include mass lesions, hemorrhage, infarct, and demyelinating disease, among others [1]. Other specific t-EVS subgroups may also be at increased risk of incidental but potentially actionable findings on neuroimaging, including those with subjective symptoms but no objective signs, younger patients with post-traumatic onset of symptoms, elderly patients, those unresponsive to repositioning maneuvers, and those with short-term recurrence of symptoms [21]. Vestibular migraine may mimic a variety of causes of dizziness and vertigo, including t-EVS, but often has associated headache and other migrainous features (ie, photophobia, phonophobia, visual aura) [20,22]. Imaging is not required to Dizziness and Ataxia diagnose vestibular migraine. To summarize, most patients with t-EVS will not require imaging unless there are atypical features such as lack of nystagmus on provoking maneuvers (eg, Dix-Hallpike) or lack of response to treatment maneuvers (eg, Epley). CT Head With IV Contrast There is no relevant literature regarding the use of CT head with IV contrast in the evaluation of t-EVS.
Dizziness and Ataxia. Triggered by specific head movements (eg, Dix-Hallpike maneuver). Initial imaging. Brief episodic vertigo triggered by specific head movements (eg, Dix-Hallpike maneuver) is referred to as triggered episodic vestibular syndrome (t-EVS) and is most commonly due to BPPV; however, more ominous central causes may clinically mimic BPPV and are collectively referred to as CPPV [1]. BPPV results from mobile debris (canaliths) in the vestibular labyrinth. The diagnostic criteria for BPPV are clinical and well established [18-20]. Imaging evaluation in BPPV with typical nystagmus on Dix-Hallpike testing is unnecessary. In contrast, patients with CPPV present with symptoms of t-EVS but negative or atypical Dix-Hallpike testing are at an increased risk of having an acute central cause of vertigo identified on imaging [6]. Potential causes of CPPV include mass lesions, hemorrhage, infarct, and demyelinating disease, among others [1]. Other specific t-EVS subgroups may also be at increased risk of incidental but potentially actionable findings on neuroimaging, including those with subjective symptoms but no objective signs, younger patients with post-traumatic onset of symptoms, elderly patients, those unresponsive to repositioning maneuvers, and those with short-term recurrence of symptoms [21]. Vestibular migraine may mimic a variety of causes of dizziness and vertigo, including t-EVS, but often has associated headache and other migrainous features (ie, photophobia, phonophobia, visual aura) [20,22]. Imaging is not required to Dizziness and Ataxia diagnose vestibular migraine. To summarize, most patients with t-EVS will not require imaging unless there are atypical features such as lack of nystagmus on provoking maneuvers (eg, Dix-Hallpike) or lack of response to treatment maneuvers (eg, Epley). CT Head With IV Contrast There is no relevant literature regarding the use of CT head with IV contrast in the evaluation of t-EVS.