What is the patterson external ethmoidectomy championed by Harrison?
It compose of removal of entire medial wall from the level of the ethimodal vessels inferiorly and across the floor as far as the infraorbital nerve and lateral to this if necessary.
It allows greater access and 4 mm -7 mm of decompression.
It also can combine with lateral orbitotomy.
Orbital margin is stronger than the orbital walls.
Compression of the orbital contents will produce “blow out”of the inferior and or medial wall