Orbital Traumatic Pathologies

Ultrasound is useful for exploring traumas; after suture of an open wound, without any pression and in a sterile environment. Evaluation of motility is crucial. Orbital cellulitis may be pre-septal (grade 1) or orbital, retroseptal (grade 2) or correspond to a subperiosteal abscess (grade 3). Grade 4 corresponds to the orbital abscess. In post-traumatic carotid cavernous fistula, B-mode shows a significant dilation of the superior ophthalmic vein with an average height of the peaks less than 40% at tissue sensitivity (T) in standardized A-mode. Doppler confirms the diagnosis by showing a high peak systolic velocity, between 50 and 70 cm/s, with a low resistive index, less than 0.60. Retrobulbar hematoma is rare. Ultrasound can be performed as an emergency procedure and can reveal a small lesion at the very beginning. A-mode allows for more precise analysis of the echotexture. One of its real contributions, in addition to diagnosis, is to allow evacuation of the hematoma under ultrasound guidance. Terson syndrome associates an intraocular hemorrhage, related to a subarachnoid hemorrhage. Before vitrectomy, ultrasound reveals a retro equatorial hemorrhage, and must look for retinal detachment, choroidal thickening and maculopathy. A-mode may note a slight increase in the size of the optic nerve, persistent in abduction. For muscle trauma (incarceration, disintegration, or laceration), ultrasound is useful, combining B- and A-modes. It may show an abnormality of volume or echotexture, particularly revealing a hematoma. For the optic nerve, ultrasound is useful for traumatic optic neuropathy and for avulsion of the optic nerve head.