###Rationale: Ans: A ( floor of the orbit) Ref: Basok Essentials of ophthalmology 5th edition, pg no 421: kanski 7th edition clinical ophthalmology, pg no 873- 874Explanation:Blow out fracture of orbit:Caused by a sudden increase in the orbital pressure by an impacting object of size > 5cm like tennis ball or fist.The fracture usually involves the floor of the orbit, along the thin bone covering the infra orbital canal.Two types:Pure Blow Out fracture does not involve the orbital rim or the other bonesImpure Form involves other bonesSymptoms:Diplopia - due to the entrapment of muscle into the fracture , intraorbital hemorrhage or injury to the muscle itselfDouble Diplopia - Diplopia in both upgaze & downgaze due to entrapment of both Inferior rectus (Depression) & inferior oblique (Elevation)Periocular ecchymosis & edemaEnophthalmosInfraorbital nerve anaesthesia Investigations: X-ray (WATER'S view) - kTear Drop Sign ' because of the protruding orbital tissue from the floor if the orbit into the maxillary antrum.Management:Conserv ative management with antibiotics & anti inflammatory drugsOrbital floor repair with bone graft, silicone plate within 2 weeksIndications:Fracture involving > one third of the floorPersisting diplopiaEnophthalmos > 2mmBlow-In Fracture:Sudden rise of pressure in the maxillary antrum due to trauma to the face with subsequent elevation of bone fragments into the orbit.

###Answer: OPTION A IS CORRECT.
###Question: Tear drop sign: (Repeat)
###Options:
A. floor of orbit
B. Retinoblastoma
C. Dry eyes
D. Congenital nasolacrimal duct obstruction
