Thorax-XRAY and CT

THORAX XRAY AND CT

1. THORAX Normal Anatomy of Thorax With X-Ray and CT DR . NITIN WADHWANI Prof . and H.O.D department of Radio-diagnosis, DY Patil medical college, hospital & research institute Kolhapur

2. (1) X-Ray

3. There are 3 types of chest films; Antero-Posterior (AP) Postero -Anterior (PA) Lateral X-ray Chest Introduction

4. Normal Chest X-Ray PA LAT

5. True Ribs

6. The mediastinum lies within the   thorax  and is enclosed on the right and left by  pleurae . It is surrounded by the chest wall in front, the  lungs  to the sides and the  spine  at the back Mediastinum It contains all the organs of the thorax except the lungs.

7. The mediastinum can be divided into an upper (or superior) and lower (or inferior) part: 1) The  superior mediastinum  starts at the  superior thoracic aperture  and ends at the  thoracic plane . 2) The  inferior mediastinum  from this level to the  diaphragm . This lower part is subdivided into three regions, all relative to the  pericardium  – the anterior mediastinum being in front of the pericardium, the  middle mediastinum  contains the pericardium and its contents, and the  posterior mediastinum  being behind the pericardium.

8. How To Interpret Chest X-ray

9. * Assessing The Image Quality, “RIPE” mnemonic is used; Rotation , Inspiration, Position, Exposure(Penetration). Check for rotation measure the distance from the medial end of each clavicle to the spinous process of the vertebra at the same level, which should be equal Check adequacy of inspiration Nine pairs of ribs should be seen posteriorly in order to consider a chest x-ray adequate in terms of inspiration Check penetration one should barely see the thoracic vertebrae behind the heart Check exposure One needs to be able to identify both costophrenic angles and lung apices * “RIPE”

10. Rotation : The clavicles should appear symmetrical and be seen as equal length. The distance between the thoracic spinal process and clavicular heads should be equal

11. 2) Inspiration : On good inspiration, the diaphragm should be seen at the level of the 8th – 10th posterior rib or 5th – 6th anterior rib .

12. 3)Position : PA, AP, or lateral view? The standard chest X-Rays consists of a PA and lateral chest X-Ray. The normal lateral chest x-ray view is obtained with the left chest against the cassette. If the x-ray is a true lateral, the right ribs are larger due to magnification and usually projected posteriorly to the left ribs (Figure-3).

13. 4) Exposure / Penetration : Ideally, you should be able to see the heart, the blood vessels, and the intervertebral spaces. Exposure should be adequate if you are able to see approximately T4 vertebra and spinal process. If the film is underexposed, you will not be able to see them . If the film is overexposed, details of bone structures will be lost .

14. Underexposed PA X-Ray film.You can not appreciate thoracic vertebras.

15. Figure-7: Overexposed PA X-Ray film. You are able to see all vertebral bodies with obvious intervertebral spaces.

16. The interpretation of a chest X-Ray should be approached systematically. For chest X-Rays, there is a classic schematic: “ABCDEF.” You should first check the patient’s name and date of the film. You should also check the side marker, and the film position (PA or AP). Finally, you should check patient’s position such as supine, erect or semi-erect. The analysis is ABCDEF: Airways Bones Cardiac Diaphragm Extra-thoracic tissues Fields and Fissures Interpretation of a chest X-Ray

17. Mnemonic Explanation Note A Airways The trachea should be central or slightly to the right. If it is deviated, check whether it is due to the patient's position or another pathological cause. B Bones and soft tissues Assess the bones visible in the image from top to bottom. The edges of the bones should be smooth, otherwise a fracture may be indicated. Also assess for bone density, oedema or metastatic lesion. C Cardiac On a PA image, the heart's width should be less than 50% of the chest width. On an AP image, it should be between 50-60% of the chest width. D Diaphragm The right diaphragm is normally higher than the left. The costophrenic and cardiophrenic angles should be clearly visible. The blunting of those angles may indicate effusion. E Edges of the Heart The edges of the heart should be clearly defined. Otherwise, there may be consolidation in the adjacent lung lobes. F Fields and Fissure Check for any absence of normal lung markings in both fields. Also check for opaque masses, consolidation, or fluid. G Great Vessels or Assess the aorta and pulmonary vessels. The aortic knob should be visible. Gastric bubbles A normal gastric bubble can be seen below the left diaphragm. H Hila The left hilum is normally higher than the right. Visible lymph nodes around the hila are an abnormal finding. Also check for masses or calcification around the hila .

18. Airways

19. Bones

20. Cardiac

21. E – EXTRATHORACIC TISSUES Mostly this means as the lung parenchyma. Lung fields can be divided into zones: upper, middle, and lower zones (Figure-12); Upper zone: from the apex to 2nd costal cartilage . Middle zone: between 2nd and 4th costal cartilage. Lower zone: between 4th and 6th costal cartilage

22. Fissures

23. (2) CT

24. CT at level of Aortic Arch

25. CT at level of Carina

26. THANKYOU - Prathamesh Kotawadekar (Radio JR1)