Caloric test assesses the function of

Ans. c (Lateral semicircular canal) (Ref. Bhargava 5th Ed, 36; Dhingra 4th ed., 43)CALORIE TEST (HALLPIKE TEST)# To test vestibular function by stimulating the Labyrinth by water of 30degC (cold) and 44degC (hot).# Position of patient: Head raised to 30deg from horizontal in supine position to bring horizontal semicircular canal in vertical position.# Inference: Nystagmus produced (COWS).WaterNystagmusCold (30degC)Opposite SideWarm (44degC)Same SideInterpretationa) Normal: Time taken from start of irrigation to end point of Nystagmus is taken and it is 80-120 seconds.b) Canal paresis:Duration of Nystagmus shortened, i.e., < 80 sec.Indicates depressed function of ipsilateral Labyrinth, vestibular nerve and vestibular nuclei.Seen in:1. Meniere's disease; 2. Acoustic neuroma; 3. Vestibular neuritis 4. Vestibular nerve section; 5. Postural vertigoDirectional preponderance: Duration of Nystagmus increases, i.e., > 120 sec.