[Types and treatments of blow-out fractures]

A total of ten cases of blow-out fractures of the orbit was investigated as to the signs and symptoms, image findings of conventional views of Caldwell and Waters' and of coronal CT. According to the locations of fractures, medial, floor and medial-floor types were classified. Fractured bone tips were classified to depressive and trapdoor types. Fractures often occur posterior to the eyeball, the inferior rectus muscle showed dislocation and cylinder-like hypertrophy. Contrary to the reports in the past, the inferior rectus muscle did not show entrapment in the herniated portion. Caldwell view is superior to Waters' view in demonstrating fractures at the medial orbital wall. As to the choice of treatment in the majority of cases, conservative methods are indicated. Images by CT are used in determining surgical methods, the depressive type without clinical improvement after two weeks is the indication for the surgical treatments.