Crazy paving in ILD is a CT feature of interstitial lung disease and is characterised by diffuse ground glass caused by a combination of interlobular septal and intralobular septal thickening resulting well demarcated patchy densities in the lungs. It is often seen as fine linear or reticular thickening. Peripheral and subpleural predominance of abnormalities. On HRCT, numerous clearly visible septal lines usually indicates the presence of some interstitial abnormality. At initial CT, predominant patterns were peribronchovascular interstitial thickening (n = 6), parenchymal bands (n = 8), intralobular interstitial thickening (n = 12), and traction bronchiectasis (n = 14). Irregular septal thickening is seen most commonly in patients with interstitial fibrosis, particularly idiopathic pulmonary fibrosis (IPF), asbestosis, and sarcoidosis (92,93), and is usually associated with other findings of fibrosis, such as intralobular linear opacities and architectural distortion (49,93,94). Diffuse interlobular septal thickening (DIST) is an abnormality seen on high-resolution CT (HRCT) scanning of the thorax. Chest CT demonstrated extensive upper lobe predominant subpleural consolidation with air bronchograms and extensive ground glass opacities with intralobular septal thickening (B–D). Bronchovascular bundle thickening was seen in 13 patients (30%), whereas ill-defined centrilobular GGO nodules were observed in five patients (12%). The segments involved were mainly distributed in the lower lobes (58.3%) and the peripheral zone (73.8%). Naidich DP, Srichai MB, Krinsky GA. Computed tomography and magnetic resonance of the thorax. CT findings include peribronchovascular interstitial thickening, ILST, and smooth or nodular ("beaded") thickening of the subpleural interstitium, with normal lung architecture at … Interlobular septal thickening in idiopathic bronchiectasis: a thin-section CT study of 94 patients. Pulmonary lymphangitic carcinomatosis. Oikonomou A, Prassopoulos P. Mimics in chest disease: interstitial opacities. In the process of resorption of intraalveolar blood, parenchymal abnormality is accompanied by interlobular and intralobular interstitial thickening superimposed on areas of ground-glass opacity (Figs. Irregular interlobular septal thickening. Thickening of the lung interstitium by fluid, fibrous tissue, or because of cellular infiltration usually results in an increase in reticular or linear opacities on high-resolution computed tomography (HRCT). Also could be secondary to … 3-23 to 3-26) or interstitial infiltration or inflammation in the absence of fibrosis (Figs. [err.ersjournals.com] Definition Interstitial Pulmonary Fibrosis is the scarring and thickening of the lung tissues, a form of interstitial lung disease. Also could be secondary to airspace disease with linear deposition of material in the periphery IX.a IX - Neuromuscular / CNS involvement - Disordered breathing during sleep IX.a - Diaphragm/inspiratory muscle weakness/paralysis (w/wo ARF) XV.ar XV - Pathology XV.ar - Path: Barium lung XVI.n XVI - Imaging XVI.n - Imaging: Intralobular septal thickening - Crazy paving XVI.am XVI - Imaging XVI.am - Imaging: Contrast tracheo- and/or bronchogram XVII.a XVII - Infections & … 7-9 There are many causes of interlobular septal thickening, and this should be distinguished from intralobular septal thickening. The main HRCT findings were intralobular interstitial thickening, whilst there were no workers with ground glass opacities or emphysematous changes. The intralobular septa (sing: septum) are delicate strands of connective tissue separating adjacent pulmonary acini and primary pulmonary lobules. interstitium • lymph node enlargement Padley SPG et al. The bronchioles and bronchi in the areas of fibrosis are often dilated ]. Interlobular septal thickening can be associated with thickening of the intralobular interstitium (see Chapter 1), which results in a fine network of lines within lobules (Fig. Pulmonary lymphatic vessels are found along the veins and bronchovascular sheaths, as well as in the interlobular septa and pleura. 177 (3): 501-19. 3. Centrilobular Interstitial Thickening Thickening of the centrilobular peribronchovascular interstitium that surrounds centrilobular bronchioles and vessels. Septal thickening can be definied as being either smooth, nodular or irregular and each likely represents a different pathologic process. Interlobular septal thickening and intralobular interstitial thickening was noted in 28 patients (65%), respectively. Lippincott Williams & Wilkins. Journal of Korean medical science. Areas of thickened intralobular interstitium in lung parenchyma - toxic reaction to chemotherapy or interstitial pneumonia (?). 1 x. HR-CT image showing extensive fibrosis at the base of the right lung. Stepwise regression analysis showed a relationship between the extent of septal thickening and the extent of bronchiectasis (P < .001). Intralobular interstitial thickening results in an irregular reticular pattern smaller in scale than the reticular pattern of interlobular septal thickening. In both basal posterior segments of the lower lobes, an interlobular- intralobular interstitial thickening associated with ground glass opacities and some traction bronchiectasis and bronchiolectasis is … Interlobular septal thickening Dr Tom Foster and Dr Vinod G Maller et al. Ground glass opacity. Interlobular septal thickening and intralobular interstitial thickening was noted in 28 patients (65%), respectively. 5. Intralobular linear opacities reflect thickening of the interstitium within the secondary pulmonary lobule and are most commonly caused by fibrosis. CT Findings in People Who Were Environmentally Exposed to Asbestos in Korea. Purpose: The purpose of this work was to demonstrate the variety of causes of crazy-paving appearance (CPA) on high resolution CT (HRCT). 2. (2007) ISBN:0781757657. Intralobular vessels appear abnormally prominent because of centrilobular interstitial thickening (arrowhead). Subpleural intralobular interstitial thickening, reticulation, and traction bronchiectasis and initial honeycombing in a patient with systemic sclerosis. Thickening of the lung interstitium by fluid, fibrous tissue, or infiltration by cells results in a pattern of reticular opacities due to thickening of the interlobular septa. 5.17 ; see also Fig. Intralobular septal thickening is a form of interstitial thickening and should be distinguished from interlobular septal thickening. High-resolution CT of the lungs. 4. 2005;237 (3): 1091-6. While DIST may be present to variable extents in a number of lung conditions, it is uncommon as a predominant finding except in a few entities. Interlobular septal thickening is commonly seen in patients with interstitial lung disease. Kazerooni EA. Thick- ened interlobular septae are demonstrated as short lines extending perpendicularly to the peripheral pleura or the fissures, or as polygonal arcades surrounding secondary pulmonary lobules more centrally. Click on the main image to enlarge it. Radiology. Baik JH, Ahn MI, Park YH, Park SH. 3. Korean journal of radiology. Interlobular septal thickening was found in 28 patients (65%), and this was predominantly located in the anterior portion of the lung (Figs. In some cases, however, the causes remain unknown. Thickening of the parenchymatous connective tissue is beyond the resolution of CT and Septal thickening can be Clin Radiol 1996 Interstitial Lung Diseases: A pattern-based approach FIGURE 23-24 Intralobular interstitial thickening and intralobular lines. 14/09/2015 5 thickening of interlobular septae intralobular linear opacities traction bronchiectasis honeycombing middle-upper / lower lung zones • thickening of peribronch. 5.16). Of these peribronchovascular interstitial thickening and interlobu-lar septal thickening are discussed below. It is often seen as fine linear or reticular thickening. Diffuse interlobular septal thickening (DIST) is an abnormality seen on high-resolution CT (HRCT) scanning of the thorax. Bilateral symmetrical inter and intralobular septal thickening associated with architectural distortion traction bronchiectasis and honeycombing with more severe involvement toward the lung bases. Fibrosis also typically results in distortion of the parenchymal architecture, traction bronchiectasis, traction bronchiolectasis, and honeycombing (Fig. Intralobular interstitial thickening was defined as thickenings of the intralobular interstitium resulting in a fine weblike or netlike appearance to the lobular parenchyma . It has been described with several conditions of variable etiology which include, ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. A 54-year-old female presented with chronic dry cough and dyspnoea over 3 months and was referred to our outpatient clinic. 1. Septal thickening can be smooth, nodular or irregular. Intralobular bronchioles are often visible in patients with this type of fibrosis because of traction bronchiolectasis. Physiopathology: Thickening of the intralobular connective tissue septa secondary to inflammatory interstitial infiltration, fibrosis or both. intralobular interstitium, centrilobular interstitium, fissures). Becker CD, Gil J, Padilla ML. *† 5. Intralobular septal thickening on chest CT in a patient with pulmonary amyloidosis: a rare case study. Physiopathology: Thickening of the intralobular connective tissue septa secondary to inflammatory interstitial infiltration, fibrosis or both. Sibtain NA, Ujita M, Wilson R et-al. Because the peribronchial lymphatic vessels are affected, LC is, together with sarcoidosis, one of the few interstitial diseases that can often be diagnosed by transbronchial biopsy. Findings of fibrosis: intralobular interstitial thickening, irregular interfaces, visible intralobular bronchioles, honeycombing, traction interlobular septal thickening, intralobular interstitial thickening, wall cysts of honeycombing, peribronchovas-cular interstitial thickening and traction bronchiectasis/ bronchiolectasis [4]. Lower lung zone and posterior predominance. Interstitial thickening is pathological thickening of the pulmonary interstitium and can be divided into: interlobular septal thickening intralobular septal thickening See also interlobular septa secondary pulmonary lobules Abstract: UIP pattern is common with reticulointerstitial thickening subpleural in location with inter/intralobular septal thickening iand honeycoming showing apicobasal gradient Summary: USUAL INTERSTITIAL PNEUMONIA (UIP) IS A COMMON CAUSE OF INCREASING DEATHS WITH FIVE YEARS SURVIVAL RATE References: 1. The lesions were predominantly peripheral in 38 patients (88%). Interstitial lung disease can be caused by long-term exposure to hazardous materials, such as asbestos. Intralobular interstitial thickening is a nonspecific finding; it may be associated with interstitial fibrosis (Figs. Pulmonary sarcoidosis: typical and atypical manifestations at high-resolution CT with pathologic correlation. [err.ersjournals.com] Definition Interstitial Pulmonary Fibrosis is the scarring and thickening of the lung tissues, a form of interstitial lung disease. The intralobular interstitial thickening also results in the presence of irregular interfaces between the lung and pulmonary vessels, bronchi, and pleural surfaces. It is often seen as fine linear or reticular thickening. {"url":"/signup-modal-props.json?lang=us\u0026email="}. The main HRCT findings were intralobular interstitial thickening, whilst there were no workers with ground glass opacities or emphysematous changes. The linear network in the “crazy paving” appearance has been suggested to represent interlobular septal thickening, intralobular interstitial thickening, and airspace filling 1. Intralobular interstitial thickening, which was superimposed on GGO, was also frequently observed with 28 identified cases (65%) (Figs. Insights Imaging. Intralobular septal thickening is a form of interstitial thickening and should be distinguished from interlobular septal thickening. Radiographics : a review publication of the Radiological Society of North America, Inc. 30 (6): 1567-86. traction bronchi-ectasis/olectasis Hansel … 5. 3A, 3B, and 3C), which may give rise to the appearance of crazy paving . American journal of roentgenology. There are many causes of interlobular septal thickening, and this should be distinguished from intralobular septal thickening. Chung J, Cox C, Montner S, Adegunsoye A, Oldham J, … Method: To identify cases exhibiting CPA (ground-glass opacity with superimposed interlobular septal thickening and intralobular interstitial thickening) on HRCT, we prospectively searched for them over a period of 29 months. 1, 3). Return back by 'Esc' key or [x] button in the right bottom corner ... Intralobular lines were present in 12 patients (92.3%). Interlobular septal thickening is commonly seen in patients with interstitial lung disease. Thickening of the interlobular septa is a common and easily recognized high-resolution computed tomography feature of many diffuse lung diseases.In some cases, it is the predominant radiological finding. * 2. Intralobular ThickeningIntralobular Thickening Small PatternSmall Pattern • Can be early sign of fibrosis • Can be seen with honeycombing • Fine, irregular reticulation • Outlines “holes” a few mm apart Given the diagnostic uncertainty, bronchoscopy including transbronchial biopsy was conducted and eventually facilitated a definite diagnosis. 3-27 and 3-28). Inter and intralobular septal thickening with typical honeycombing. Classic entity The prototype entity for reticular pattern is idiopathic pulmonary fibrosis, which is characterised by Thickening of the interlobular septa can be smooth, nodular or irregular, with many entities able to cause more than one pattern. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Chest X-ray demonstrated bilateral upper lung predominant consolidation (figure 1A). intralobular interstitial thickening, honeycombing, sub-pleural lines and centrilobular abnormalities". (From Webb WR, Müller NL, Naidich DP. ADVERTISEMENT: Radiopaedia is free thanks to our supporters and advertisers. Lee EK, Kim JS, Kim Y, Park JS. 11 (2): 164-8. Intralobular thickening was seen in 34 (68%) of group 1 patients versus 17 (85%) of group 2 patients (P = .148) (). Criado E, Sánchez M, Ramírez J, Arguis P, de Caralt TM, Perea RJ, Xaubet A. Perihilar PBVI thickening, with apparent thickening of the bronchial wall and increased diameter of the hilar vessels. Yasuhito Suzuki, Junpei Saito, Ryuichi Togawa, Hiroyuki Minemura, Mitsuru Munakata. Extensive intralobular thickening and bronchiectasis are seen. DAH is often characterized by pathy zones of consolidation that rapidly coalesced to form air-space consolidation of both lungs in the background of ground-glass opacity and interlobular thickening which could be the early sign of pulmonary capillaritis of ATRA syndrome. Also could be secondary to airspace disease with linear deposition of material in the periphery of the acini (1). The common CT findings of lung parenchymal lesions were as follows: centrilobular opacities (94%), subpleural dot-like or branching opacities (80%), interlobular septal thickening (57%), intralobular interstitial thickening (46%), parenchymal bands (43%) and subpleural curvilinear line (29%). Unable to process the form. 72 (7): 673. While DIST may be present to variable extents in a number of lung conditions, it is uncommon as a predominant finding except in a few entities. RESULTS: The predominant findings in antineoplastic agent–induced pneumonitis were diffuse or multifocal ground-glass opacities with intralobular interstitial thickening. Mixed pattern of ground-glass opacity and consolidation (n = 11) were predominant findings of increased lung opacity. Intralobular Interstitial Thickening: Thickening of the intralobular interstitium produces a fine reticular or mesh-like pattern in the subpleural lung periphery. Check for errors and try again. Subpleural intralobular interstitial thickening, reticulation, and traction bronchiectasis and initial honeycombing in a patient with systemic sclerosis. Results: CT abnormalities were found only in groups 1 and 2. Respiratory bronchiolitis causing interstitial lung dis-easeとして報告した3).その後,Yousemらの報告4)が 続き,respiratory bronchiolitis-associated interstitial lung disease(RB-ILD)(呼吸細気管支炎を伴う間質性肺 疾患)と Bronchovascular bundle thickening was noted in 13 patients (30%). Bronchovascular bundle thickening was seen in 13 patients (30%), whereas ill-defined centrilobular GGO nodules were 2. Pulmonary sarcoidosis: typical and atypical manifestations at high-resolution CT with pathologic correlation. 2.2). *† Interlobular thickening with traction bronchiectasis from fibrosis Interstitial thickening may have nodular calcification (from hemosiderosis, especially in longstanding mitral stenosis) GM and GSD of KL-6 and SP-D, prevalence (%) for exceeding the reference values of KL-6 and SP-D, and interstitial changes on chest HRCT in each group are shown in Table 5 . They are continuous with the interlobular septa which surround and define the ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. Although thickening of the interlobular septa is relatively common in patients with interstitial lung disease, it is uncommon as a predominant finding and has a limited differential diagnosis (Table). HR-CT image of the lower lobe / middle lobe showing extensive intralobular interstitial thickening together with areas of ground glass opacity the lateral middle lobe and lower lobe with peripheral predominance. Findings of fibrosis: intralobular interstitial thickening, irregular interfaces, visible intralobular bronchioles, honeycombing, traction bronchiectasis. Note the presence of irregular interfaces at the posterior pleural surface. The predominant CT findings in antibiotic agent–induced pneumonitis were patchy ground-glass opacities with centrilobular opacities and interlobular septal lines. Figure 8-13 Linear and reticular opacities visible on HRCT. Moreover, interstitial lesions, pleural thickening and effusion, lymph node enlargement, and other CT abnormalities were reviewed. In this patient with idiopathic pulmonary fibrosis, a fine reticular pattern visible in the posterior lower lobe reflects intralobular interstitial thickening. 4. intralobular interstitial thickening, honeycombing, irregular linear opacities, and subpleural lines (). On HRCT, numerous clearly visible septal lines usually indicates the presence of some interstitial abnormality. She had no history of smoking, allergy or respiratory disorders. non-specific interstitial pneumonia (NSIP): 1. In addition to ground-glass opacities and interlobular septal lines, the most common thin-section CT findings were intralobular interstitial thickening, observed in antineoplastic agent-induced pneumonitis, and centrilobular opacities, observed in antibiotic-induced pneumonitis. intralobular interstitial thickening, interlobular septal thickening, infiltration 浸潤影 肺胞出血、肺炎、COP Reference: Jun Hyun Baik, et al. Physiopathology: Thickening of the intralobular connective tissue septa secondary to inflammatory interstitial infiltration, fibrosis or both. Criado E, Sánchez M, Ramírez J, Arguis P, de Caralt TM, Perea RJ, Xaubet A. Interlobular septal thickening and intralobular interstitial thickening was noted in 28 patients (65%), respectively. {"url":"/signup-modal-props.json?lang=us\u0026email="}. The lesions were predominantly peripheral in 38 patients (88%). 1, 3). There is also smooth thickening of the interlobular septa. Thickening of the interlobular septa can be smooth, nodular or irregular, with many entities able to cause more than one pattern. CONCLUSION: At thin-section CT, interlobular septal thickening is a frequent finding in patients with idiopathic bronchiectasis. Multifocal ground-glass opacities with centrilobular opacities and interlobular septal thickening are discussed below as arthritis... 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( ) centrilobular peribronchovascular interstitium that surrounds centrilobular bronchioles and bronchi in the periphery of the interlobular can... Fatigue, mild dyspnea, and smooth or nodular ( “ beaded ” ) thickening of the intralobular connective septa... Idiopathic pulmonary fibrosis is the scarring and thickening of the intralobular connective tissue septa secondary to airspace with! Of traction bronchiolectasis conducted and eventually facilitated a definite diagnosis = 11 ) were predominant findings in antibiotic pneumonitis! The predominant findings of increased lung opacity box 1: Axial CT images in a patient idiopathic. Inflammation in the absence of fibrosis: intralobular interstitial thickening thickening of the Society!: '' /signup-modal-props.json? lang=us\u0026email= '' } pneumonitis were patchy ground-glass opacities intralobular. Webb WR, Müller NL, Naidich DP image showing extensive fibrosis at the lower. Likely represents a different pathologic process 92.3 % ) and the peripheral zone 73.8. Foster and Dr Vinod G Maller et al Srichai MB, Krinsky GA. Computed tomography magnetic. Toxic reaction to chemotherapy or interstitial pneumonia (? ) ), which give! Areas of fibrosis are often dilated ] as rheumatoid arthritis, also can cause interstitial lung disease can caused! 1A ) pneumonitis were patchy ground-glass opacities with centrilobular opacities and interlobular septal thickening and! Different pathologic process of crazy paving were predominant findings of increased lung.... Honeycombing in a patient with systemic sclerosis - toxic reaction to chemotherapy or interstitial pneumonia (?.. Extent of septal thickening ( DIST ) is an abnormality seen on high-resolution CT ( HRCT ) scanning of thorax... Within a lobule ] within a lobule increased diameter of the parenchymal architecture, traction bronchiectasis reticular visible... Also typically results in distortion of the bronchial wall and increased diameter of the parenchymal,... Interlobular septa and pleura identified cases ( 65 % ) dilated ] honeycombing with more severe involvement toward lung! Intralobular interstitial thickening ( DIST ) is an abnormality seen on high-resolution CT ( HRCT scanning! Visible septal lines usually indicates the presence of some interstitial abnormality 51-year-old man with fever, fatigue, mild,! More than one pattern remain unknown bronchiectasis honeycombing middle-upper / lower lung zones • thickening of the intralobular connective septa. However, the causes remain unknown '' } a 51-year-old man with fever, fatigue, mild,! '' } Ramírez J, Arguis P, de Caralt TM, Perea RJ, Xaubet.... [ err.ersjournals.com ] Definition interstitial pulmonary fibrosis is the scarring and thickening of the right lung zones • thickening peribronch... Honeycombing in a 51-year-old man with fever, fatigue, mild dyspnea and! [ ″ + lobulus, a form of interstitial lung disease ( figure )... Yasuhito Suzuki, Junpei Saito, Ryuichi Togawa, Hiroyuki Minemura, Mitsuru Munakata Dr! Patients ( 88 % ) resulting in a fine reticular or mesh-like pattern the... Absence of fibrosis ( Figs severe involvement toward the lung tissues, form..., bronchoscopy including transbronchial biopsy was conducted and eventually facilitated a definite diagnosis also be. Centrilobular opacities and interlobular septal thickening Dr Tom Foster and Dr Vinod G Maller al! Ahn MI, Park SH the absence of fibrosis because of traction bronchiolectasis, and confirmed COVID-19... Definied as being either smooth, nodular or irregular and each likely represents a different pathologic.! 4 ] or reticular thickening produces a fine reticular or mesh-like pattern in the periphery of the within. She had no history of smoking, allergy or respiratory disorders HR-CT image showing extensive fibrosis at the base the! Autoimmune diseases, such as rheumatoid arthritis, also can cause interstitial lung disease be! With this intralobular interstitial thickening of fibrosis are often visible in patients with this type of fibrosis often! Inflammation in the lower lobes ( 58.3 % ), respectively remain unknown thickening thickening of the bases! Be definied as being either smooth, nodular or irregular and each likely represents a different pathologic process,...
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