[Coronal CT in the indication of the endoscopic surgery of the sinus]

In this paper the Authors affirm that Functional Endoscopic Sinus Surgery is the technique of choice for treatment of nonneoplastic pathologies of paranasal sinuses, particularly in chronic infective and polypoid sinusitis. Furthermore, they confirm CT scans are mandatory in preoperative planning in order to delineate precisely the structures surrounding the surgical field (the lamina papyracea and possible dehiscences, the brain, the lacrimal duct, the internal carotid artery and the optic nerve), and thereby avoid any possible damage during surgery. If endoscopic examination and clinical history suggest a massive involvement of ethmoid cavities, both axial and coronal CT scans are necessary. Inasmuch as the crucial point in the development of chronic sinus pathology is the ostio-meatal complex, the Authors indicate that this structure can be clearly identified and studied by means of coronal CT scans, since in this case it is not necessary to clarify the depth of the nasal fossae, but, instead, to reveal the exact situation and configuration of the two fundamental lamellae, the uncinate process and the bulla. These structures lie on a vertical plane and cannot be studied with axial CT scans without reviewing several series scans made in close proximity, which increases the patient's exposure to x-rays as well as the expense of the study. This paper is an attempt to shorten and rationalize routine radiologic procedures when a limited ethmoid involvement, previously detected by careful endoscopic examination, is under investigation.