J Oral Maxillofac Surg 70:1627-1632, 2012 Can Systematic Computed Tomographic Scan Assessment Predict Treatment Decision in Pure Orbital Floor Blowout Fractures? Thomas Schouman, MD, MSc,* Delphine S. Courvoisier, PhD,† Christopher Van Issum, MD,‡ Andrej Terzic, MD, DDS,§ and Paolo Scolozzi, MD, DDS Purpose: To describe and evaluate the reliability and the accuracy of a specific computed tomog- raphy-based assessment in predicting treatment decisions for pure orbital floor blowout fractures (BOFs). Materials and Methods: In this retrospective cohort study, the charts of all patients presenting with isolated BOFs from January 2009 through April 2011 at the University Hospital of Geneva were reviewed. The systematic computed tomographic assessment included the following 3 parameters: 1) ratio of the fractured orbital floor; 2) maximal height of periorbital tissue herniation, and 3) a 4-grade muscular subscore describing the position of the inferior rectus muscle relative to the level of the orbital floor. The parameters’ predictive value regarding the treatment decision (conservative vs surgical) was assessed by logistic regression and relative operating characteristic curves. Results: Forty-eight patients (24 male) were included. The patients’ mean age was 49.5 years. The ratio of the fractured orbital floor, the maximal height of periorbital tissue herniation, and the muscular subscore were significant predictors in univariate analysis (P = .02, P = .006, P = .001, respectively), whereas, in a multivariate analysis, only muscular subscore remained a significant predictor (P = .003) and reached a similar predictive ability as the 3 parameters together. Conclusions: The present study showed that the severity of inferior rectus muscle displacement is the most important independent predictive radiologic factor in the treatment decision-making process for pure BOFs. This systematic computed tomographic assessment is a valuable tool for a better understand- ing of BOF management overall. Further studies are needed to establish its clinical relevance. © 2012 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 70:1627-1632, 2012 The management of orbital floor fractures remains controversial. In the vast majority of cases, the oper- ative indication results from a personal in-house algo- rithm, which includes a wise mix of nonstandardized clinical/radiologic findings, including diplopia, en- ophthalmos, and the type (linear or comminuted) and size of the fracture. The defect area often has been advocated as one of the main independent criteria influencing the choice of treatment for surgery and even the choice of the specific implant material used. The following 2 area thresholds for the affected area have been proposed as the primary indicator for sur- gery: 1) larger than 1 cm 2 ; and 2) more than 50% of the entire orbital floor area. 1-3 Thus far, no consensual methods have been reported to evaluate the affected area accurately. Therefore, treatment decision-making recommendations are often based on vague and sub- jective interpretations of the fractured area on a com- Received from the University Hospital and Faculty of Medicine of Geneva, Geneva, Switzerland. *Service of Oral and Maxillofacial Surgery, Department of Surgery. †Biostatistician, Service of Clinical Epidemiology. ‡Service of Ophthalmology. §Service of Oral and Maxillofacial Surgery, Department of Surgery. Service of Oral and Maxillofacial Surgery, Department of Surgery. Address correspondence and reprint requests to Dr Schou- man: Service of Oral and Maxillofacial Surgery, Department of Surgery, University Hospital and Faculty of Medicine of Geneva, 1211 Geneva, Switzerland; e-mail: thomas.schouman@psl.aphp.fr © 2012 American Association of Oral and Maxillofacial Surgeons 0278-2391/12/7007-0$36.00/0 http://dx.doi.org/10.1016/j.joms.2012.03.006 1627