Diagnosis of small vestibular schwannomas using constructive interference steady state sequence

Area of Science:

• Radiology
• Neuroimaging

Background:

• Vestibular schwannomas (VSs) are tumors that develop on the nerve connecting the inner ear to the brain.
• Accurate and early diagnosis is crucial for effective management and treatment planning.

Purpose of the Study:

• To evaluate the diagnostic accuracy of constructive interference steady state (CISS) sequencing compared to gadolinium-enhanced T1 (GdT1) magnetic resonance imaging (MRI) for screening small VSs.
• To assess neuroradiologists' diagnostic confidence using CISS imaging versus GdT1 MRI.

Main Methods:

• Retrospective chart review of VS/benign cerebellopontine angle tumors from 2011 to 2015.
• Two blinded, board-certified neuroradiologists independently reviewed axial CISS and GdT1 MRI sequences.
• Neuroradiologists completed questionnaires assessing diagnostic confidence for VS detection.

Main Results:

• CISS sequencing demonstrated an overall sensitivity of 93.5% for VS detection.
• High sensitivities were observed across most tumor locations, with lower sensitivity for intralabyrinthine locations (62.3%).
• Neuroradiologists reported high confidence in diagnosing VSs with CISS, comparable to GdT1 MRI.

Conclusions:

• CISS MRI is a viable alternative to GdT1 MRI for screening small vestibular schwannomas.
• Intralabyrinthine lesions and those measuring ≤3.0 mm are more challenging to detect with CISS.
• CISS imaging provides high sensitivity and specificity, with high diagnostic confidence for neuroradiologists.