Evaluation of the oblique fissure on lateral chest radiographs in coal workers pneumoconiosis

Abstract

The oblique fissure separates the upper lobe from the lower lobe in the left lung and the upper lobe from the lower and middle lobes in the right lung. The aim of the present study was to compare the projection of the oblique fissure observed on lateral chest radiographs of retired coal mine workers who had coal worker's pneumoconiosis (CWP) with that of healthy men. The study included 120 men divided into three groups: retired coal miner patients diagnosed with CWP (group 1), men ≥38 years of age with no CWP (group 2, first control group), and men ≤37 years of age with no CWP (group 3, second control group). The projection of the oblique fissure observed on lateral chest radiographs (left side) were evaluated using geometric morphometrics. Geometric morphometric analysis of each sample was performed using 11 pre-specified landmarks designated on X-ray images, using tpsDig2 software. A text file containing the landmark coordinates of the 120 samples was created, and the data in the text file was statistically analyzed using Morpheus software. The projection of the oblique fissure differed significantly between the CWP patients and the control groups (p<0.05). We suggest that the difference in the projection of the oblique fissure between men with and without CWP was attributable to a protrusion in the fissure caused by nodules that developed in the lungs of coal miners after years of dust inhalation (Tab. 4, Fig. 4, Ref. 30).