<prompt> Thumb sign in lateral X- ray of neck seen in -EpiglottitisInternal haemorrhageSaccular cystCa epiglottis  <response>: In epiglottis: A plain lateral soft tissue radiograph of neck shows the following specific features:Thickening of the epiglottisthe thumb signAbsence of a deep well-defined valleculathe vallecula sign.ALSO KNOW Steeple sign i.e. narrowing of subglottic region is seen in chest X-ray of patients of laryngotracheobronchitis i.e. croup. 