Normal chest x ray- Radiology Basics

An approach to the normal chest xray and how to read them. Imaging for the resident and undergraduates.

1. Normal Chest X- Ray - Dr Sandeep Singh Awal Dept of Radiodiagnosis GRMC

2. The PA View Positioning : All radio-opaque objects on the patient to be removed Patient ,upright, faces the cassette chin up Shoulders rotated forward ,pressed in contact with the cassette side marker Centering at T5 at right angles Focus to Film Distance of 6 feet Exposure made on full inspiration

3. AP VIEW Positioning : Patient back against the cassette, with the upper edge of cassette above the lung apices . Shoulders are rotated laterally and supported by the side of the trunk Centering : middle of the cassette at right angle Side marker Exposure made on full inspiration

4. LATERAL VIEW Positioning : patient turned to bring the side under investigation in contact with the cassette Arms raised over the head Mid-axillary line - coincides with middle of the film Centering : middle of the cassette at right angles EXPOSURE done in full inspiration

5. Film Quality PA or AP view. Upright/Erect or Supine Breath : Inspiration or Expiration X-ray penetration : Under- or Over- Rotation

6. PA VIEW AP VIEW SCAPULA DO NOT OVERLAP THE LUNG FIELDS SCAPULA OVERLAPPING THE LUNG FIELDS CLAVICLES PROJECT On THE LUNG FIELDS CLAVICLES ARE ABOVE THE APICES OF LUNG NO CARDIAC MAGNIFICATION CARDIAC MAGNIFICATION

7. PA view AP view

8. Viewing the CHEST X RAY Patient details,history Technical aspects Bones Trachea and mediastinum Diaphragm and costophrenic angles Hila Lungs Soft tissues

9. TECHNICAL ASPECTS CENTERING/ROTATION : medial aspects of clavicles-equidistant from vertebral spinous processes

10. Spinous process is closer to right clavicle => left sided rotation seen L

11. ADEQUATE PENETRATION – Vertebral bodies and disc spaces should be just visible through the cardiac shadow. Underpenetration – miss an abnormality hidden by another structure Overpenetration – loss of visibility of low density lesions

12. ADEQUATE INSPIRATORY EFFORT Good inspiratory film : 6 complete Anterior ribs 10 complete Posterior ribs Poor Inspiratory film : Less than 6 anterior ribs seen

13. P oor inspiratory film 4 anterior ribs visible False postitive findings : cardiomegaly ( ctr 0.55) opacity adjacent to aortic knuckle inhomogenous opacification of bilateral lower lung fields

14. Bones Each rib - anomaly Clavicles Scapulae and b/l humerus if visible Lower cervical and thoracic spine LOOK FOR ANY FRACTURES OR LESIONS Bifid left 4 th rib

15. Fracture clavicle

16. Soft tissues Confirm presence or absence of breast shadows. Breast shadows may obscure lung bases or costophrenic angles Skin folds may mimic pneumothorax Lateral chest wall ( subcutaneous emphysema ) Left sided mastectomy

17. Trachea Trachea – midline translucency, slight inclination to right in its lower half If Trachea shifted- pneumothorax Collapse fibrosis

18. HEART Position Cardiothoracic ratio : ratio betn the max transverse diam of heart and max width of the thorax above the costophrenic angles CTr = A+B / C If >0.5(adults) and >0.6(children) in a good quality film => Cardiomegaly

19. A=3 B = 5 C = 12 A+B = 8 units CTr = A+B/C = 8/12 = 0.66 Imp - Cardiomegaly

20. RIGHT HEART BORDER SVC RIGHT ATRIUM IVC LEFT HEART BORDER AORTIC KNUCKLE PULMONARY TRUNK LEFT VENTRICLE svc RA IVC A P LV

21. HILAR REGIONS 97% of subjects- left hilum is higher than right. formed where superior pulmonary vein meets the lower pulmonary artery Clearly defined CONCAVE lateral borders Normal lymph nodes not visible

22. Lung There are 3 lobes in right lung and 2 in left . Right lung Upper lobe Middle lobe Lower lobe. Left lung : also contains the lingula,part of the upper lobe . Upper lobe; this contains the lingula Lower lobe.

23. LUNG On a PA VIEW , for descriptive purposes the lungs are divided into three zones separated by imaginary horizontal lines Upper zone - above the anterior end of the second ribs M idzone - between the second and fourth anterior ribs Lower zone - below the level of the fourth anterior rib.

24. Analyse each lung separately Identify any change in density Compare with opposite lung Compare upper, mid and lower zones B ronchovascular markings – prominent if present on more than 2/3rds of lung laterally Inferior markings are normally more prominent

25. Lobes Right upper lobe:

26. Right middle lobe:

27. Right lower lobe:

28. Left lower lobe:

29. Left upper lobe with Lingula:

30. Lingula:

31. Left upper lobe - upper division:

32. Oblique/major fissure – separates upper lobe from lower lobe seen on lateral view Extends from T4/T5 posteriorly to diaphragm anterioinferiorly . Horizonta /minor fissure – separates upper and middle lobes of Right lung. Can be s een on PA and lateral views Seen running from the hilum to sixth rib in axillary line in pa film. Posteriorly ends at the right major/oblique fissure

33. Accessory fissures Azygous fissure (0.4 % of pop) – comma shaped, mostly right sided in the apex of the lung Forms due to abnormal migration of azygous vein during development . invagination of the azygous vein through the apical portion of right upper lung .

34. Inferior accessory fissure – oblique line running from the cardiophrenic angle toward the hilum. separates medial basal from other basal segments. Commoner on right side. Superior accessory fissure –separates the right lower lobe into superior and basal segments. Inferior accessory fissure

35. Diaphragm Right hemidiaphragm is higher than the left. Assess curvature of b/l hemidiaphragms to identify diaphragmatic flattening or bulge Assess bilateral Costophernic angles- normally acute & well defined Rule out any free gas under hemidiaphragm

36. Thank you