CASE 46: Acute blowout fracture
Acute blowout fracture of the right orbit. A, Primary position; B, limited downgaze in right eye (reverse leash effect); C, severely limited upgaze of the right eye (leash effect). D, Coronal CT shows defect in right orbital floor with orbital contents prolapsed into the maxillary sinus.
This 6-year-old boy was struck in the right eye by the heel of a playmate’s shoe while wrestling at play 6 days ago. The right eye was moderately swollen immediately after the injury. The child saw double after he was struck, and he continues to see double at all times.
Visual acuity is OD 20/30 and OS 20/20. No significant refractive error is present. The eyes are straight in the primary position and 6/9 stereo dots (80 seconds) are seen. Depression of the right eye is moderately limited and elevation of this eye is severely limited. There is numbness over the medial aspect of the right inferior orbital rim. CT scan of the orbits shows a bony defect of the right orbital floor with prolapse into the maxillary sinus of the orbital contents, possibly including the right inferior rectus muscle.
Acute blowout fracture of right orbital floor.
Removal of orbital contents from the maxillary sinus and repair of the fracture defect with a splint.
Acute blowout fracture of the orbit wall (usually the floor) is now treated in most cases by the oculoplastic surgeon. The surgical approach to the orbital floor is through a subciliary incision made in the skin of the lower lid or through an inferior fornix incision. With either incision, inferior orbital rim periosteum is incised below the inferior orbital septum, and the periosteum is elevated to expose the orbital floor defect. Prolapsed orbital contents are carefully extracted from the maxillary sinus, and a thin plastic sheet, either preformed or cut and shaped to size, is placed over the defect. Unfortunately, adhesions in and around the orbital soft tissue, including the inferior rectus, can cause restricted eye movement even when freeing of the prolapsed material has been complete. If motility continues to be limited after surgical repair of a blowout fracture, appropriate eye muscle surgery, usually inferior rectus recession, on the involved side can be carried out. However, if paresis of the inferior rectus is present, freeing of restriction to elevation must be followed by an inferior rectus resection, or, if the inferior rectus is nonfunctioning, muscle transfer must be done by shifting the horizontal recti to the inferior rectus insertion.