ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Thickened septal lines may occur from a variety of processes, including fibrosis, pigment deposition, and pulmonary hemosiderosis. Conclusion: Interlobular septal thickening (Kerley B lines) in the lung apex is a specific sign for pulmonary congestion, although not exclusive (since in ILD there may be apical reticulation). They are perpendicular to the pleural surface and extend out to it. Kerley B lines These are short parallel lines at the lung periphery. The originally described Kerley C lines are now designated as due to overlapping Kerley C lines. 2. Kerley lines are described as types A, B or C. 1. 3. This sign can be found in various viral pneumonias such as parainfluenza, Hantavirus, and SARS [ 9, 22 ]. The Kerley lines represent interlobular sheets of abnormally thickened or widened connective tissue that are tangential to the x-ray beam (Fig. The B lines in this case occur when ultrasound waves meet thickened, edematous interlobular septa. On the contrary, in antibiotic-induced pneumonitis, predominant radiographic findings were patchy ground-glass opacities with centrilobular opacities and interlobular septal lines. The first two of these are most easily recognized and have a limited differential diagnosis. This is an excellent example of Kerley B lines.These lines are created by interlobular septal thickening, typically created by fluid collecting within the pulmonary interstitium.Classically Kerley B lines are seen with cardiogenic pulmonary edema, where left ventricular failure causes increased intravascular hydrostatic pressure at the level of the pulmonary capillaries. These lines are best visualized in the subpleural and juxtadiaphragmatic regions of the lung, where they outline the anterior and posterior margins of secondary lobules. Kerley D lines are exactly the same as Kerley B lines, except that they are seen on lateral chest radiographs in the retrosternal air gap . Subpleural lines and interlobular septal thickening are shown in the right lung, and irregular lines were present in left lung. 5A and 5B) with or without intralobular lines superimposed on ground-glass opacity (crazy paving) [ 8] (Fig. Other causes of Kerley lines are listed in Table 3.2. The most common cause of interlobular septal thickening, producing Kerley A and B lines, is pulmonary edema, as a result of pulmonary venous hypertension and distension of the lymphatics (Figs. Sekar T, Swan KG, Vietrogoski RA. Interlobular Septal Lines (Kerley's Lines) Posted by Rathachai Kaewlai, M.D. Disease Interlobular Septa This image is a panoramic view of the lung showing almost rectangular secondary lobules surrounded by interlobular septa (cream borders) The distal bronchioles (teal) and pulmonary arteriole (royal blue are shown in the centre of a lobule in the right lower corner. These are 2-6 cm long oblique lines that are <1 mm thick and course towards the hila. not A lines). In combination with peribronchial cuffing and increased cardiothoracic ratio, it allows differentiation between cardia … Equivalents: septal thickening, septal lines. Kirchner J. Kerley Blines are small, horizontal, peripheral straight lines demonstrated at the lung bases that represent thickened interlobular septa on CXR. B-lines represent the interlobular and/or intralobular septal thickening, most associated with pulmonary edema and interstitial disorders. HRCT is the best modality for the demonstration of Kerley A lines. They represent edema of the interlobular septa and though n… On chest radiographs they are seen to cross normal vascular markings and extend radially from the hilum to the upper lobes. These are (a) interlobular septal thickening, (b) honeycombing, and (c) intralobular interstitial thickening, also described as intralobular lines by its HRCT appearance . Interlobular septal thickening on pulmonary HRCT. Septal thickening can be definied as being either smooth, nodular or irregular and each likely represents a different pathologic process. Kerley lines are named after Sir Peter James Kerley (1900-1979), a British radiologist who in addition to describing the interstitial lines now known as Kerley lines, was a co-founder of the Faculty of Radiology (later to become the Royal College of Radiologists), and also attended to King George VI 3,4. Interlobular septal thickening is commonly seen in patients with interstitial lung disease. Check for errors and try again. Interlobular septal lines and centrilobular opacities were observed more frequently in antibiotic agent-induced pneumonitis, and intralobular interstitial thickening was observed more frequently in antineoplastic agent-induced pneumonitis. [from HPO] Term Hierarchy. This may be because of lymphatic engorgement or oedema of the connective tissues of the interlobular septa. 6) and consolidation (Figs. These diseases are usually also located in the central network of lymphatics that surround the bronchovascular bundle. Case 1: Kerley A, B and C lines (arrowed). This is an excellent example of Kerley B lines.These lines are created by interlobular septal thickening, typically created by fluid collecting within the pulmonary interstitium.Classically Kerley B lines are seen with cardiogenic pulmonary edema, where left ventricular failure causes increased intravascular hydrostatic pressure at the level of the pulmonary capillaries. They usually occur when pulmonary capillary wedge pressure reaches 20-25 mmHg. sarcoid, lymphangitic carcinomatosis, pulmonary edema). This may be because of lymphatic engorgement or edema of the connective tissues of the interlobular septa. Interlobular septal thickening is a common sign on thin-slice chest CT; it may be seen in the presence of interstitial fluid, cellular infiltration, or fibrosis. They represent thickening of the interlobular septa that contain lymphatic connections between the perivenous and bronchoarterial lymphatics deep within the lung parenchyma. Interlobular septal thickening (Kerley B lines) in the lung apex is a specific sign for pulmonary congestion, although not exclusive (since in ILD there may be apical reticulation). They may be very subtle, but if seen in the context of clinical suspicion of heart failure, then septal lines are a strong indicator of interstitial oedema. GGO, vascular enlargement, interlobular septal thickening more frequently occurred in patients with COVID-19, which distribution features were peripheral, bilateral, involved lobes > 2. Kerley Alines are linear opacities extending from the periphery to the hila caused by distention of anastomotic channels between peripheral and central lymphatics 2. FIGURE 3-1 Linear and reticular opacities visible on HRCT. There are many causes of interlobular septal thickening, and this should be distinguished from intralobular septal thickening. 3 . Asbestosis (peripheral interlobular septal thickening, subpleural findings, parenchymal lines, pleural plaques) Peripheral. IPF; Collagen-vascular; Asbestos; EP; COP; DIP; Drug rxn; Cystic . Septal lines / Kerley B lines: visible horizontal interlobular septa caused by pulmonary edema; Prominent pulmonary vessels and perihilar alveolar edema (the hilar shadow has a butterfly or “ bat wing ” appearance) Basilar interstitial edema; Bilateral pleural effusions [12] Thieme Medical Pub. On HRCT, numerous clearly visible septal lines usually indicates the presence of some interstitial abnormality. 2011;196 (4): W375-9. This may be because of lymphatic engorgement or oedema of the connective tissues of the interlobular septa. This corresponds to the average size of a lobule. The average distance between two B-lines in the septal variant is roughly 6–7 mm. They represent thickened subpleural interlobular septa and are usually seen at the lung bases. They also have shown them to beabsent along fissural surfaces. Kerley C lines are short lines which do not reach the pleura (i.e. 5A and 5B) with or without intralobular lines superimposed on ground-glass opacity (crazy paving) and consolidation (Figs. ภาพที่ 1 แสดงให้เห็น Kerley's B lines ซึ่งเป็นเส้นตรงสั้นๆ ตั้งฉากกับ chest wall ที่ right lower lobe ในผู้ป่วยที่มี interstitial pulmonary edema With more advanced disease, septal lines (Figs. 3.2 and 3.3). not B or D lines) and do not course radially away from the hila (i.e. Septal lines, also known as Kerley lines, are seen when the interlobular septa in the pulmonary interstitium become prominent. Chest radiology, plain film patterns and differential diagnoses. (F) Chest CT scan of a 70-year-old male patient after 3 days of treatment. Classically Kerley B lines are seen with cardiogenic pulmonary edema, where left ventricular failure causes increased… 17-nov-2016 - History: 60 year old male with lower extremity edema and shortness of breath. ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. Kerley lines are named after Sir Peter James Kerley (1900-1979), an Irish radiologist who in addition to describing the interstitial lines now known as Kerley lines, was a co-founder of the Faculty of Radiology (later to become the Royal College of Radiologists), and also attended to King George VI 3,4. Classification Kerley A lines. These lines represent interlobular septa, which are usually less than 1 cm in length and parallel to one another at right angles to the pleura.They are located peripherally in contact with the pleura, … Chest Radiology: A Resident's Manual. 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