Possibilities of visualisation of the diaphragm using computed tomography

Introduction . The diaphragm is the main respiratory muscle and performs many non-respiratory functions. Somatic dysfunction of the diaphragm, as identifi ed by osteopathic physicians, is associated with a variety of clinical symptoms: pain, abnormalities of breathing pattern, posture, venous outfl ow from the lower extremities, etc. There are very few computed tomography (CT) studies of the diaphragm, although the diaphragm is well visualised in CT studies of the thoracic and abdominal cavities. CT is an accessible diagnostic method with few limitations. The aim of the study : to investigate the structure and topography of the diaphragm using computed tomography in patients with and without a history of cancer. Materials and methods . The cross-sectional study was performed by a continuous sampling of patients who applied to the clinic of MC «Admiralty Shipyards» from May to August 2024. The patients were examined using a Toshiba Aquilion PRIME computed tomography scanner in the supine position, breath hold on deep inhalation. Visualisation of the diaphragm was performed on CT of the chest and abdomen in axial, coronal and sagittal planes — multiplanar reconstructions. All patients aged 25–90 years were included in the study and distributed according to nosological groups: 1st — 7 patients 26–49 years old who were referred for control examination; 2nd — 34 patients 50–90 years old with respiratory diseases; 3rd — 30 patients 50–83 years old with abdominal and retroperitoneal diseases; 4th — 87 patients 42–88 years old with verifi ed malignant neoplasm (MN) of various localisations in anamnesis; 5th — 18 patients 54–78 years old with suspected MN of various localisations who had not undergone surgical treatment. Inclusion criteria: operations on lungs, liver, oesophagus and stomach, anomalies of diaphragm development; injuries of diaphragmatic nerve. Disturbances of the structure and topography of the diaphragm and liver were evaluated in points: 2 points — pronounced changes; 1 point — weakly pronounced changes; 0 points — no changes. The presence or absence of partial loss of contact between the diaphragm and the liver was also evaluated. Results . All subjects of group 1 had no disorders of the structure and topography of the diaphragm and liver. Relaxation of the left dome of the diaphragm (70,6 %) was characteristic of patients with respiratory diseases and was statistically signifi cantly more frequent than in patients with abdominal diseases (40 %), p =0,026. Relaxation of the right dome of the diaphragm was most common in patients with suspected MN (78,2 %). There may be concomitant deformation of the contour of the adjacent part of the liver. A high degree of correlation ρ=0,8 ( p <0,001) was found between these pathological features. Deformation of the diaphragm in the form of its uneven thickening due to spasm of separate muscle fi bres was typical for patients with MN (87,3 %) and with suspected MN (94,4 %). Partial loss of connection of the diaphragm with the liver was most often observed in patients with suspected MN (72,2 %). The pathological signs observed were not related to the localisation of MN, suggesting that they were caused by the severe stress experienced by these patients. Conclusion . This study demonstrates a high frequency of detecting deformations of the diaphragm and liver contours, as well as abnormalities of their topography on CT in different groups of patients. These abnormalities are especially frequent in cancer patients and patients with suspected MN, which may be associated with a state of severe stress. It is recommended to include the description of the diaphragm in the CT protocol of the thoracic and abdominal cavities. This information can be used for diagnostics and control of treatment results in patients with various diseases, including confi rmation of the results of osteopathic correction of diaphragm dysfunction.