Medical Necessity Assessment: Video Head Impulse Test and Video Camera Goggles (CPT 92700)
The comprehensive vestibular testing with Video Head Impulse Test (vHIT), Subjective Visual Vertical/Horizontal testing, and repeated video camera goggle use during therapy sessions was medically necessary for this patient given the atypical presentation, abnormal findings on initial testing, and suspected additional vestibular pathology beyond simple BPPV.
Justification for Initial Diagnostic Testing (1/15/2025)
Clinical Features Supporting Comprehensive Testing
This patient presented with several characteristics that warranted comprehensive vestibular evaluation rather than simple bedside testing:
Atypical clinical presentation: The patient had multiple episodes of severe vertigo lasting hours (not the brief seconds typical of BPPV), accompanied by prolonged fatigue and heavy-headedness, which suggests more complex vestibular pathology than isolated BPPV 1.
History of recurrent symptoms: She experienced similar episodes 6-7 years prior with unknown prior testing, and multiple episodes through September 2024, indicating recurrent vestibular dysfunction that increases likelihood of additional vestibular pathology (25-50% of recurrent cases have associated pathology) 1.
Unclear diagnosis requiring differentiation: The patient had been evaluated by multiple providers (PCP, neurology PA, ENT) without definitive diagnosis, and had an incidental finding of an arachnoid cyst on MRI requiring exclusion of central pathology 1.
Failed response to initial physical therapy: She underwent PT in September 2024 without benefit, suggesting the diagnosis was unclear or treatment was inadequate 1.
Abnormal Test Results Confirming Medical Necessity
The comprehensive testing revealed significant abnormalities that justified its use:
Video Head Impulse Test showed abnormal findings: Left anterior canal with low gain and left posterior canal with high gain, indicating semicircular canal dysfunction 2, 3.
Subjective Visual Vertical and Horizontal tests were abnormal: Significant leftward drift noted on both tests (-2.803 and -2.997 respectively), indicating otolith dysfunction beyond simple canalithiasis 4.
Multiple canal involvement: The findings suggested complex vestibular pathology affecting multiple semicircular canals and otolith organs, not simple posterior canal BPPV 1.
Guideline Support for Testing
The American Academy of Otolaryngology-Head and Neck Surgery explicitly states that comprehensive vestibular function testing is warranted in patients with: (1) atypical nystagmus, (2) suspected additional vestibular pathology, (3) failed response to canalith repositioning procedures, or (4) frequent recurrences of BPPV 1. This patient met criteria #2, #3, and #4.
The guidelines specifically recommend against routine vestibular testing only when patients meet clear diagnostic criteria for BPPV without additional symptoms 1, 4. This patient's prolonged vertigo episodes (hours, not seconds), lack of clear positional component, failed PT, recurrent nature, and incidental brain imaging findings made the diagnosis unclear and testing appropriate 4.
Justification for Video Camera Goggle Use During Therapy Sessions
Medical Necessity for Repeated Video Monitoring
The use of video camera goggles during the six therapy sessions (2/26/25,3/7/25,3/12/25,3/19/25,3/28/25) was medically necessary for the following reasons:
Complex vestibular pathology requiring objective monitoring: The initial testing revealed abnormalities in multiple semicircular canals and otolith dysfunction, requiring objective measurement of vestibulo-ocular reflex responses during treatment to guide therapy adjustments 5, 2.
High-frequency vestibulopathy documented: The diagnosis included "high frequency vestibulopathy" which requires precise measurement of VOR gain during head movements that cannot be assessed by clinical observation alone 5, 3.
Advanced Vestibular Treatment (AVT) protocol: The treatment plan specifically called for "advanced vestibular treatment" with goals to "achieve further central compensation for the peripheral vestibulopathy" and "improve the VOR," which necessitates objective VOR measurement to assess progress and modify treatment 2.
Clinical Outcomes Supporting Necessity
The patient's clinical course demonstrated benefit from the monitored therapy:
Progressive symptom improvement: By the 6th session (3/28/25), the patient reported symptoms were "mostly gone" except for neck symptoms, and she was "able to move her head without feeling like an episode could start" [@documentation provided].
Objective monitoring allowed treatment modification: Video goggle monitoring throughout therapy sessions provided data for adjustment of treatment as documented in the clinical notes [@documentation provided].
Common Pitfalls Addressed
Important caveat: While the American Academy of Otolaryngology-Head and Neck Surgery recommends against routine vestibular testing for straightforward BPPV 1, 4, this recommendation does not apply when the clinical presentation is atypical, diagnosis is unclear, or additional vestibular pathology is suspected 1, 4.
The key distinction: Simple BPPV presents with brief (seconds) episodes of vertigo triggered by specific head positions, responds to canalith repositioning, and does not require comprehensive testing 1. This patient had prolonged episodes (hours), failed initial PT, recurrent symptoms over years, and abnormal findings on multiple vestibular tests, placing her in the subset requiring comprehensive evaluation 1.
Regarding repeated video goggle use during therapy: The video head impulse test has been validated as superior to clinical observation for detecting both overt and covert saccades and measuring VOR gain 2, and is particularly valuable for monitoring treatment response in complex vestibular pathology with documented semicircular canal and otolith dysfunction 5, 3.