Relationship between the extent of fracture and the degree of enophthalmosin isolated blowout fractures of the medial orbital wall

Purpose: This study investigated the relationship between the extent of fra cture and enophthalmos in blowout fractures of the medial orbital wall. Patients and Methods: Nine patients with isolated blowout fractures of the medial orbital wall, confirmed by computed tomography scans, were evaluated . The area of fracture and the volume of herniated orbital tissue were dete rmined from computed tomography scans using simple linear measurements, Eac h of the calculated values for area and volume were compared with the degre e of enophthalmos to determine whether there was any significant relationsh ip between them, Results: Enophthalmos increased proportionally as the area of fracture or t he volume of herniated orbital tissue increased (P <.05). The area of fract ure and the volume of herniated orbital tissue associated with 2 mm of enop hthalmos were 1.9 cm(2) and 0.9 mt, respectively, as calculated from the re gression curve, Conclusion: Enophthalmos of 2 mm or more, which is a frequent indication fo r surgery, can be expected when the area of fracture is 1.9 cm(2) or more, or the volume of herniated orbital tissue is 0.9 mt Or more. (C) 2000 Ameri can Association of Oral and Maxillofacial Surgeons.