4 Densities The big two densities are: (1) WHITE - Bone (2) BLACK - Air The others are:(3) DARK GREY- Fat(4) GREY- Soft tissue/waterAnd if anything Man-made is on the film, it is:(5) BRIGHT WHITE - Man-made
5 Techniques - Projection P-A (relation of x-ray beam to patient)
10 Film Quality (cont) Was film taken under full inspiration? -10 posterior ribs should be visible.A really good film will show anterior ribs too, there shouldBe 6 to qualify as a good inspiratory film.
14 TECHNIQUE, cont. Rotation Determined by distance between spinous process & medial clavicleAffects heart size & shape, aortic tortuosity, density of lung fields
15 PenetrationIs the film over or under penetrated ? if under penetrated you will not be able to see the thoracic vertebrae. If overpenetrated you will see the thorasic vertebrae beyond the heart with details.
18 Lung Anatomy Right Lung Left Lung Superior lobe Middle lobe Inferior lobeLeft Lung
19 Lung Anatomy on Chest X-ray These lobes can be separated from one another by two fissures.The minor fissure separates the RUL from the RML, and thus represents the visceral pleural surfaces of both of these lobes.Oriented obliquely, the major fissure extends posteriorly and superiorly approximately to the level of the fourth vertebral body.Grossly, these lobes can be separated from one another by two fissures which anatomically correspond to the visceral pleural surfaces of those lobes from which they are formed. The minor fissure separates the RUL from the RML, and thus represents the visceral pleural surfaces of both of these lobes. The minor fissure is oriented horizontally, extending ventrally from the chest wall, and extending posteriorly to meet the major fissure. Generally, the location of the minor fissure is approximately at the level of the fourth vertebral body and crosses the right sixth rib in the midaxillary line. The right major fissure is more expansive in size than the minor fissure, separating the right upper and middle lobes from the larger right lower lobe. Oriented obliquely, the major fissure extends posteriorly and superiorly approximately to the level of the fourth vertebral body. The major fissure extends anteroinferiorly, intersecting the diaphragm at the anterior cardiophrenic angle
21 Lung Anatomy on Chest X-ray The right upper lobe (RUL) occupies the upper 1/3 of the right lung.The right upper lobe (RUL) occupies the upper 1/3 of the right lung. Posteriorly, the RUL is adjacent to the first three to five ribs. Anteriorly, the RUL extends inferiorly as far as the 4th right anterior rib.
23 Lung Anatomy on Chest X-ray The right middle lobe is typically the smallest of the three, and appears triangular in shape, being narrowest near the hilumThe right middle lobe is typically the smallest of the three, and appears triangular in shape, being narrowest near the hilum.
25 Lung Anatomy on Chest X-ray These two lobes are separated by a major fissure, identical to that seen on the right side.The portion of the left lung that corresponds anatomically to the right middle lobe is incorporated into the left upper lobe.These two lobes are separated by a major fissure, identical to that seen on the right side, although often slightly more inferior in location. The portion of the left lung that corresponds anatomically to the right middle lobe is incorporated into the left upper lobe.It is important to understand that in most individuals, interlobar fissures are usually not completely formed; in some individuals there may be complete absence of a fissure thus losing the demarcation between lobes on gross examination.In general, fissures are not readily identifiable on plain films, with only small portions typically visualized at best. This is because fissures which are composed of only two layers of visceral pleura, may not present a significant radiographic interface and will not produce a shadow. However, if there is fluid within the pleural space or if the visceral pleura is thickened, fissures may be seen in their entirety.
27 Left upper lobe with Lingula: Lobes (continued)Left upper lobe with Lingula:
28 Lung Anatomy on Chest X-ray The lobar architecture of the left lung is slightly different than the right.Because there is no defined left minor fissure, there are only two lobes on the leftThe lobar architecture of the left lung is slightly different than the right. Because there is no defined left minor fissure, there are only two lobes on the left; left upper
33 The Silhouette SignAn intra-thoracic radio-opacity, if in anatomic contact with a border of heart or aorta, will obscure that border. An intra-thoracic lesion not anatomically contiguous with a border or a normal structure will not obliterate that border.
35 Systematic Approach Bony Framework Soft Tissues Diaphragm and Pleural SpacesLung Fields and HilaMediastinum and HeartAbdomen and Neck
36 Systematic Approach Bony Fragments Ribs Sternum Spine Shoulder girdle ClaviclesFirst, inspect the BONY FRAMEWORK of the chest You should be able to count and number the ribs, inspect the capulae, humeri and shoulders, and clavicles, and seethe diaphragms overlying the posterior aspects of the 10th or 11th ribs (in a normal adult)> The spine and sternum are generally difficult to visualize in detail on standard PA films due to overlying shadows.
37 Systematic Approach Soft Tissues Mdiastinum Breast shadows Supraclavicular areasAxillaeMdiastinumNext, inspect the soft the SOFT TISSUES that overlie the thoracic cage Note the breast shadows,supraclavicular areas, axillae, and tissues along the sides of the chest.
50 Systematic Approach Diaphragm and Pleural Surfaces Diaphragm Dome-shapedCostophrenic anglesNormal pleural is not visibleInterlobar fissuresNext, examine the DIAPHRAGM and PLEURAL SURFACES Diaphragmatic images in the lung bases are dense, radiopaque shadows made principally by the liver on the left and the spleen on the right. The normal pleura is not visible on the chest x-ray, except where two layers come together to form the interlobar fissures.
51 Systematic Approach Abdomen and Neck Abdomen Neck Gastric bubble Air under diaphragmNeckSoft tissue massBone structure
57 Consolidation Lobar consolidation: Alveolar space filled with inflammatory exudateInterstitium and architecture remain intactThe airway is patentRadiologically:A density corresponding to a segment or lobeAirbronchogram, andNo significant loss of lung volumeConsolidation: In the lobar consolidation, a lobe is involved. The alveolar space is filled with inflammatory exudate made up of WBC, bacteria, plasma, and debris. In Pneumococcal pneumonia, the most common cause for lobar consolidation, the lobe goes through red hepatization and gray hepatization stage. In the stage of resolution, some secretions can be in the airway. The interstitium and architecture of the lung remain intact and complete recovery occurs. The lobe swells up initially and may shrink slightly later if there is significant secretions in the airway causing some obstruction. The airway is patent.Radiologically this transcribes to:1. a density corresponding to a segment or lobe2. airbronchogram, and3. no significant loss of lung volume.
58 Atelectasis Loss of air Obstructive atelectasis: No ventilation to the lobe beyond obstructionRadiologically:Density corresponding to a segment or lobeSignificant loss of volumeAtelectasis: Atelectasis means loss of air. In absorptive Atelectasis there is an obstructive lesion on the bronchus. There is no ventilation to the lobe beyond the obstruction. Gradually the air gets absorbed by pulmonary circulation. The involved lobe eventually is devoid of air and becomes atelectatic.Radiologic criteria for absorptive Atelectasis is1. a density corresponding to a segment or lobe,2. significant signs of loss of volume, and3. compensatory hyperinflation of normal lungs.
99 Pseudotumor: fluid has filled the minor fissure creating a density that resembles a tumor (arrow). Recall that fluid and soft tissue are indistinguishable on plain film. Further analysis, however, reveals a classic pleural effusion in the right pleura. Note the right lateral gutter is blunted and the right diaphram is obscurred.
101 Pneumonia:a large pneumonia consolidation in the right lower lobe Pneumonia:a large pneumonia consolidation in the right lower lobe. Knowledge of lobar and segmental anatomy is important in identifying the location of the infection