Frontobasilar fractures: Proposal for image reviewing algorithm Ulla Perheentupa a, * , Antti A. Mäkitie b, c , Jari O. Karhu d , Petri Koivunen e , Roberto Blanco Sequieros f , Ilpo Kinnunen a a Department of Otolaryngology e Head and Neck Surgery (Head: Prof. Reidar Grénman), Turku University Hospital and University of Turku, P.O. Box 52, FIe20521 Turku, Finland b Department of Otolaryngology e Head and Neck Surgery, Helsinki University Central Hospital and University of Helsinki, Finland c School of Science, Department of Industrial Engineering and Management, BIT Research Centre, Aalto University, Finland d Department of Radiology, Turku University Hospital and University of Turku, Finland e Department of Otolaryngology e Head and Neck Surgery, Oulu University Hospital and University of Oulu, Finland f Department of Radiology, Oulu University Hospital and University of Oulu, Finland article info Article history: Paper received 28 November 2012 Accepted 27 May 2013 Keywords: Maxillofacial surgery Trauma Computed tomography Algorithm abstract Objective: The aim of this study was to develop and test the utility of a novel systematic protocol to analyze CT images of patients with trauma in the anterior cranial base and upper midface. Material and Methods: The radiological data and primary reports of 27 consecutive patients with a frontal skull base fracture treated in two tertiary care hospitals from 2007 to 2011 were scrutinized. A novel algorithm for systematic image reviewing was used to assess the CT images and the findings were compared with the primary radiological reports. Results: The systematic review detected a substantial number of fractures and defects in anatomical structures that had not been systematically reported in the primary, on-call reports. Anterior skull base fracture was not initially reported in 32% of the patients; however, the algorithm detected this in 93% of them. The corresponding rates for fracture through cribriform plate were 28% and 72% and for fracture through the sella or hypophyseal area 22% and 78%. There were two fractures of the clivus and these were initially missed. Conclusions: Despite the failure to identify these fractures radiologically in the primary setting, all pa- tients were still considered to have received appropriate treatment, but, the use of an image-reviewing algorithm will enhance the specificity of CT in the diagnosis of frontobasilar fractures. Ó 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved. 1. Introduction Frontobasilar fractures are complex fractures of the skull, often associated with life-threatening head injuries (Burstein et al., 1997, Mithani et al., 2009, Schaller et al., 2012). Anatomically, the fron- tobasilar area consists of the upper midface and the anterior skull base, i.e., orbital roofs, posterior wall of frontal sinus, nasal ethmoidal complex and walls of sphenoid sinus. Injuries to this area are rare and mainly caused by high-energy trauma (Burstein et al., 1997, Perheentupa et al., 2010, Thoren et al., 2011, Calderoni et al., 2011, Naveen Shankar et al., 2012). Fractures of the cribriform area often lead to dural tearing, due to the dura lying in close proximity to the cribriform plate (Parmar et al., 2009). The dura tears in approximately one third of the patients who have sustained a fracture of the anterior skull base (Meco and Oberascher, 2004). Early evaluation of these fractures is essential for identifying and preventing complications, such as cerebrospinal fluid (CSF) leakage with a risk for meningitis, vascular injuries, compression of the optic or oculomotor nerves and defects of other cranial nerves (I, IVeVI). Fractures of this region are often complex and identification of the anatomical landmarks may be difficult. The diagnosis of frontobasilar fractures is based on clinical examination and imag- ing. Multidetector helical computed tomography (MDCT), direct coronal CT, CT cisternography with iodinated contrast medium, radionuclide cisternography and magnetic resonance (MR) imaging have been used to localize the osseous and dural defect and possible CSF leakage (La Fata et al., 2008). High-resolution multi- planar reformatted (MPR) images from thin collimation axial CT data detect CSF leakage effectively (La Fata et al., 2008, Parmar et al., 2009). Identification of CSF leakage improves with assessment of * Corresponding author. Tel.: þ358 2 313 0000; fax: þ358 2 313 3550. E-mail addresses: ulla.perheentupa@utu.fi, ulperh@utu.fi (U. Perheentupa). Contents lists available at SciVerse ScienceDirect Journal of Cranio-Maxillo-Facial Surgery journal homepage: www.jcmfs.com 1010-5182/$ e see front matter Ó 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jcms.2013.05.018 Journal of Cranio-Maxillo-Facial Surgery xxx (2013) 1e8 Please cite this article in press as: Perheentupa U, et al., Frontobasilar fractures: Proposal for image reviewing algorithm, Journal of Cranio- Maxillo-Facial Surgery (2013), http://dx.doi.org/10.1016/j.jcms.2013.05.018