Accessory fissures of the lung: evaluation by high-resolution computed tomography

Abstract

This study was performed to classify and assess the frequency of accessory fissures of the lung by high-resolution CT (HRCT) scans. The HRCT scans of 443 patients were retrospectively reviewed. After exclusion of patients with pulmonary parenchymal distortion, pleural disease or those who had had lobectomy, 186 patients were included in the study. The HRCT scans consisted of 1.5-mm sections obtained at 10-mm intervals and reconstructed with a high-spatial-resolution algorithm. In 59 of 186 patients (32%), a total of 69 accessory fissures were detected. The most common fissure was the inferior accessory fissure ( n=40; 21%, 38 on the right, 2 on the left) followed by the left minor fissure ( n=17; 9%). Other accessory fissures observed were the right superior accessory fissure ( n=2; 1%), the azygos fissure ( n=1; 0.5%) and intersegmental fissures between the medial and lateral segments of the right middle lobe ( n=3; 2%), the superior and inferior segments of the lingula ( n=2; 1%), the anterobasal and laterobasal segments of both the right ( n=1; 0.5%) and the left ( n=3; 2%) lower lobe. In conclusion, the inferior accessory fissure and the left minor fissure were the most common accessory fissures seen on HRCT examinations.

Prevalence of an Azygos Lobe using Thoracic Computed Tomography

“…Despite many published reports regarding an azygous lobe, a limited number of studies have examined its prevalence, which is reported to be 1% in cadaveric specimens, 0.4% on plain chest X-rays, and 1.2% on high-resolution CT images (8)(9)(10). A PubMed search on the prevalence of an azygous lobe detected using thoracic CT images yielded a limited number of studies (10,11). Thoracic CT images examined in our study yielded a case prevalence higher than that previously reported.…”

Morphological Study of Lung Lobes and Fissures: Anatomical Basis of Surgical and Imaging Techniques

“…Pneumonia may spread to adjacent lobes via parenchymal continuation in case of incomplete fissures. Accessory fissures often are not detected on CT scans, because of incompleteness, thick sections and orientation in relation to particular plane [15] ( Table 3).…”

A human case of an azygos lobe: Determining an anatomical basis for its therapeutic postural drainage

“…The incidence of an azygos lobe has been reported to range from 0.2% to 1.2% (Boyden, 1952;Chiba et al, 1990;Ariyürek et al, 2001;Aziz et al, 2004). Generally, the azygos lobe has been detected by classical radiography and modern clinical imaging methods (Cohen and Dooneief, 1951;Kolbenstvedt et al, 1979;Speckman et al, 1981;Pomeranz and Proto, 1986;Agrawal et al, 1995;Kobayashi et al, 1995;Caceres et al, 1998;Arslan et al, 2000).…”