<prompt> Hectic picket type of fever with rigor is important feature inCavernous sinus thrombosisLateral sinus thrombosisEthmoid sinusitisSphenoid sinusitis  <response>: B Lateral sinus thrombosis 84- Dhingra 6thLATERAL SINUS THROMBOSIS Inflammation of inner wall of lateral venous sinus with formation of an intrasinus thrombosis Complicatin of - Acute coalescent mastoiditis- Masked mastoiditis- CSOM- Cholesteatoma Clinical features1. Hectic picket. Fence type of fever with rigor. This is due to septicaemia2. Headache in early stage due to perisinus abscess3. Progressive anaemia and emaciation4. Griesingers sign- due to thrombosis of mastoid emissary vein.5. Papilloedema6. Tobey-Ayer test - record CSF pressure7. Crowe Beck test pressure on jugular vein of healthy side produces engorgement of retinal veinseen in ophthalmoscopy and supraorbital vein, Engorgement of vein subsides on release of pressure8. Tendemess along jugular veinCT MRI shows- Delta signTREATMENT1 Intravenous antibacterial therapy2 Mastoidectomy and exposure of sinus3 Ligation of internal jugular vein4 Anticoagulant therapy. 