Accessory fissures of the lung: evaluation with multiplanar reformation on 64-slice spiral CT

Abstract

Objective To classify the accessory fissures and assess the frequency of accessory fissures of the lung by 64-slice spiral CT (MSCT). Methods Of 2664 patients, 847 patients were included in this study excluding the patients with pulmonary parenchymal distortion, pleural disease or lobectomy. Allvolume raw data with a slice thickness of 0.6 mm were reformatted in sagittal and coronal orientations with 3 mm thickness and the accessory fissures were assessed. Results A total of 177 accessory fissures in 144 patients (17.0%) were detected. Most of the accessory fissures were incomplete except 10 fissures on the right lung (8.2%) and 2 fissures on the left lung (3.6%) were complete. The most common fissurewas the superior accessory fissure on the right low lobe (n = 112,13.2%) ,followed by the left minor fissure (n= 51,6.0%), the right inferior accessory fissure( n = 6,0. 7% ), the left superior accessory fissure ( n =4, 0.5%), the azygos fissure (n = 3,0.4%) and the accessory fissure on the right upper and middle lobe(n = 1,0.1%). Conclusion 64-slice CT is an efficient method to observe and classify the accessory fissures of the lung with MPR technique and can provide reliable and useful imaging information for the clinician. Key words: Lung; Anatomy,comparative; Tomography,X-ray computed