Introduction: X-ray imaging is the basic diagnostic method that is used to show the structures of the sacroiliac joints and ilium. The structures must be shown realistically, without any distortions. Purpose: The purpose of the graduation thesis is to show how different inclinations of the central beam and different positioning of the pelvis affect the images of anatomical structures in individual projections. Methods: In the graduation thesis the descriptive method was used with a review of domestic and international professional literature, as well as the experimental method. The latter was conducted in the radiology laboratory at the Faculty of Health Sciences in Ljubljana. Measurements were taken on the pelvis phantom, where we first lined the left side of the pelvis with Styrofoam panels and observed the structures of the ilium in anteroposterior and lateral projection, as well as the sacroiliac joint in the posterior semi-lateral projection. In the course of the imaging of both sacroiliac joints in anteroposterior axial projection, the inclination of the central beam was changed by 5 ° in the range of 0 ° - 45 ° in the cranial direction. The obtained images were evaluated using X-ray evaluation criteria from the literature. Results: The adjacent ilium was observed in anteroposterior projection, where the width of the iliac wing increased with the addition of panels. In the nonadjacent ilium, the width of the iliac wing decreased with the addition of panels in the lateral projection. Also, the nonadjacent sacroiliac joint in the posterior semi-lateral projection was opened in the distal part, then, with the addition of panels, it began to open towards the middle of the joint. The sacroiliac joints in anteroposterior axial projection were initially open only in the distal part, then with an increasing inclination of the central beam, they began to slowly open towards the proximal part. Discussion and conclusion: The ilium in anteroposterior projection is best shown in the 30 ° posterior semi-lateral position of the phantom, which is consistent with the cited literature. In the 20 ° posterior semi-lateral position of the phantom, the ilium is best shown in lateral projection. The position of the phantom is inconsistent with the cited literature. The individual sacroiliac joints are best shown in the 16 ° posterior semi-lateral position of the phantom, which is consistent with the cited literature. In anteroposterior axial projection, the sacroiliac joints were best shown with the central beam directed 20 ° in the cranial direction. This is consistent with the cited literature. It was found that the correct position of the patient and/or the correct inclination of the central beam is very important for a correct X-ray image of the ilium and sacroiliac joints.
|
