Objectives: Although several datasets are available concerning the advantages of using vHIT to assess vestibular dysfunction, there have been few studies comparing vHIT in acute and compensated unilateral VN. In this study we investigate VOR gain and characterize the covert and overt catch-up saccades (CSs) according to the disease course to assess the diagnostic value of vHIT during follow-up of VN. Methods:Seventy patients, diagnosed with VN from June 2013 to June 2015, were included. vHIT in the lateral semicircular canal plane were performed at initial presentation and repeated at the follow-up visit (1 month). vHIT gain ≤0.8 or gain asymmetry (GA) ≥8% was considered pathologic, and the velocity of CSs of ≥100°/s or interaural CS difference (CSD) ≥40°/s was also considered pathologic. Result:Gain in acute phase (0.6±0.3) was lower than compensated phase (0.7±0.3), and GA (31±22%), velocity of CSs (236±86°/s), and CSD (198±99°/s) at acute phase was significantly decreased at compensated phase (GA: 19±20%, velocity of CSs: 162±100°/s, CSD: 128±108°/s). The abnormal rate of vHIT was 94% (gain in 79%, GA in 80%, velocity of CSs in 89%, and CSD in 91%) at acute phase and 83% (gain in 57%, GA in 60%, velocity of CSs in 70%, and CSD in 70%) in compensated VN. Sensitivity of CSs parameters (acute: 94%, chronic: 77%) in acute and compensated phase of VN is significantly higher than that of gain parameters (acute: 81%, chronic: 64%) (P<0.05). Conclusion:The vHIT gain parameters and CSs parameters could be normalized during recovery after the acute phase of VN. CSs parameters showed higher sensitivity in detecting vestibular dysfunction than vHIT gain parameters. The vHIT is a fast and convenient test to detect vestibular deficits in VN.