• Rotation • Medial ends of bilateral clavicles are equidistant from the midline or vertebral bodies
If spinous process appears closer to the right clavicle (red arrow), the patient is rotated toward their own left sideIf spinous process appears closer to the left clavicle (red arrow), the patient is rotated toward their own right side
• Penetration • Should see ribs through the heart • Barely see the spine through the heart • Should see pulmonary vessels nearly to the edges of the lungs
Overpenetrated Film• Lung fields darker thannormal—may obscuresubtle pathologies• See spine well beyond thediaphragms• Inadequate lung detail
Underpenetrated Film•Hemidiaphragms are obscured•Pulmonary markings more prominent than they actually are
• Inspiration 1 2 • Should be able to 3 count 9-10 posterior 4 ribs 5 6 • Heart shadow should 7 not be hidden by the diaphragm 8 9 10
• Angulation 1 2 • Clavicle should lay over 3 3rd rib
Apical lordotic Same patient, not lordoticA film which is apical lordotic (beam is angled up towardhead) will have an unusually shaped heart and the usually sharp border of the left hemidiaphragm will be absent
TRACHEA• 25 mm in males 21 mm in females.• Right paratracheal stripe• Widening occurs in Lymphadenopathy, tr acheal malignancy, mediasti nal tumours, mediastinitis, pleural effusion• Normal carinal angle 60-75 degees.
HEART & MEDIASTINUM• Cardio-thoracic ratio• Transverse cardiac diameter• Increase in transverse cardiac diameter by 1.5 cm in significant.• Normal in neonates and AP projection is 60 percent• Cardiac shadow measuring more than 5.5 cm to the right signifies right atrial enlargement
DIAPHRAGM• Position, sharpness of border• Difference should be less than 3 cm between both sides.• Subdiaphragmatic air
LUNG FIELDS: FISSURES• The fissures can also help you to determine the boundaries of pathology Major Oblique Fissure Separates the LUL from the LLL Separates the RUL/RML from Right Major Fissure the RLL Separates the RUL from the Right Minor Fissure RML
LUNG FIELDS: HIDDEN AREAS• Apices• Mediastinum and hila• Behind the diaphragm
HILA• Position (left 2.5 cm higher than right)• Equal density• Clearly defined lateral borders• Lower lobe pulmonary arteries and upper lobe pulmonary veins• Diameter of pulmonary arteries should measure 10-16 mm in males and 9 – 15 mm in females.• Upper lobe veins lie lateral to the arteries and lower lobe veins lie medial to the arteries.
BRONCHIAL ARTERIES• Usually not visualized• Branches of descending thoracic aorta at T5/6 level• 2 on left; 1 on right• When enlarged appear as multiple small nodules around hila• Enlarged in cyanotic heart disease like TOF, Pulmonary atresia• Other causes include bronchiectasis or bronchial carcinoma