1、Signs in Thoracic ImagingKaruppasamy, K.1, Abhyankar-Gupta, M.1, Fewins, H.1, Curtis, J.21The Cardiothoracic Centre - Liverpool NHS Trust, 2Aintree University Hospitals NHS Foundation Trust, Liverpool, United KingdomKEY LEARNING OBJECTIVESSigns in radiology represent characteristic descriptive patte

2、rns of certain abnormalities. There are several such signs commonly associated with thoracic imaging. Clear understanding of what these signs mean helps the radiologists to interpret the images more effectively, provide a more precise prediction of an underlying pathology and avoid using lengthy des

3、criptions. We consider this poster to be useful as an educational tool for medical students, junior doctors and radiology trainees who can learn about the presence of these signs, understand what they stand for and register the images of those signs in their minds. It will also help to refresh the k

4、nowledge of radiologists.Thoracix Radiologic SignsThoracix Radiologic Signs1. Air bronchogram signAir bronchogram sign: Refers to the presence of air filled (patent) bronchi surrounded by air spaces filled with pus or fluid; simply indicates air space disease; e.g. pneumonia3. Bulging fissure signBu

5、lging fissure sign: Refers to the convex configuration a fissure takes to accommodate an adjacent swollen/enlarged lobe; e.g. Klebsiella pneumonia4. Comet tail signComet tail sign: Refers to an unusual form of focal lung collapse simulating a mass (body of the comet) with distorted vessels and bronc

6、hi (tail of the comet) radiating towards hilum; asbestos exposure in 70%6. Crazy paving signCrazy paving sign: Refers to the combination of ground glass attenuation superimposed on a network of interlobular septal thickening giving it an appearance of a surface paved with slabs of differing shapes;

7、e.g. alveolar proteinosis7. CT angiogram signCT angiogram sign: Refers to the conspicuous enhancing pulmonary vessels in a background of homogeneous low-attenuating consolidation relative to chest wall musculature; e.g. Bronchoalveolar cell carcinoma8. CT halo signCT halo sign: Refers to a zone of g

8、round-glass attenuation (the halo) surrounding a pulmonary nodule or mass; e.g. invasive aspergillosis10. Double density signDouble density sign: Refers to an abnormal density overlying right heart border; the normal right heart forms its usual density and the abnormality forms the other density; e.

9、g. left atrial enlargement11. Fallen lung signFallen lung sign: Refers to the collapse of lung away from the mediastinum when the normal central bronchial anchoring attachment of the lung is disrupted as in bronchial tear/fracture.13. Fissure signFissure sign: Normal separation of lobes by fissures

10、is not seen in perfusion scans due to low resolution; but, increased separation due to pleural thickening or effusion is seen as linear area of reduced uptake along the fissure referred as fissure sign14. Flat-waist signFlat-waist sign: Refers to the loss of concavity of the left heart border on a s

11、ymmetrical frontal CXR due to slight anterior oblique rotation of the heart seen in some cases of left lower lobe collapse.15. Fleischner signFleischner sign: Refers to the prominence of central pulmonary artery caused either by pulmonary hypertension that develops secondary to PE or by distension o

12、f the vessel by a large clot16. Gloved finger signGloved finger sign: Refers to the branching finger like opacities representing dilated bronchi filled with mucus (mucoid impaction) radiating from the hila towards the periphery; e.g. ABPA17. Golden S signGolden S sign: Refers to a reverse S shaped s

13、hadow caused by right upper lobe collapse forming the upper curve of the reverse S (concave infero-laterally) and a central mass causing the collapse forming the lower curve (convex infero-medially)18. Hampton hump signHampton hump sign: Refers to a homogeneous wedge-shaped consolidation in the lung

14、 periphery with a base contiguous to a visceral pleural surface and a rounded convex apex directed toward the hilum; associated with pulmonary infarct20. Hilar overlay signHilar overlay sign: Refers to the ability to see the hilar structures through the shadow of a mass superimposed on the hilum; in

15、dicates that the mass lies either in front or behind the hilum; e.g. anterior lymphoma or posterior neurofibroma21. Luftsichel signLuftsichel sign: Refers to the paraaortic crescentric lucency caused by the hyperexpanded superior segment of the left lower lobe in cases of left upper lobe collapse (G

16、erman = Luft- air; sichel- crescent)23. Ring around the artery signRing around the artery sign: Refers to the lucency caused by air around a vessel such as pulmonary artery; indicates pneumomediastinum24. Scimitar signScimitar sign: Refers to the curved vascular shadow (resembling a short, curved Tu

17、rkish sword called scimitar) representing an anomalous pulmonary vein draining the right lung that descends toward the diaphragm located to the right of the heart25. Signet/pearl ring signSignet/pearl ring sign: Refers to the combination of a small soft tissue attenuating circle (pulmonary artery- p

18、earl on a ring) abutting a larger soft tissue attenuating ring (wall of a bronchus- ring); ring surrounds a low-attenuating circle (air within bronchus); indicates bronchiectasis26. Silhouette signSilhouette sign: Refers to the inability to see the border of a normal structure such as heart or aorta

19、 masked by an opacity of similar density anatomically contiguous with this border; e.g. right middle lobe consolidation masking right heart border27. Split pleura signSplit pleura sign: Refers to the two layers (visceral and parietal) of enhancing pleura split by the presence of an pleural inflammat

20、ory process such as empyema28. Thymic sail signThymic sail sign: Refers to the outlining of normal thymus by air which also elevates the thymus giving it the configuration of a sail; indicates pneumomediastinum29. Tree-in-bud signTree-in-bud sign: Refers to the pattern of opacity seen in a HRCT; the

21、 terminal tufts of TIB represent inflammatory material filling respiratory bronchioles and alveolar ducts and the stalks of TIB represent filling within terminal bronchiole; e.g. Endobronchial TB30. Westermark signWestermark sign: Refers to an area of o!igemia with minimal change in lung volume dist

22、al to a large PE; this regional oligemia is caused either by mechanical obstruction to blood flow by the clot or by reflex vasoconstrictionCONCLUSIONWe hope that this pictorial review with description helps the viewers to remember and recall the signs during their practice. ACKNOWLEDGEMENTSWe would like to thank Dr John Reynolds (Heartlands Hospital