Brown sign is seen in

Brown sign also called Pulsation sign is seen in glomus tumours. Glomus tumor is the most common benign neoplasm of middle ear; originating from the glomus bodies. It is extremely vascular. Thus, when ear canal pressure is raised with Siegel's speculum, the tumour pulsates vigorously and then blanches; reverse happens with the release of pressure. This is called Brown sign. Reference : page 109 Diseases of Ear, Nose and Throat & Head and Neck surgery - Dhingra 6th edition