[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-456729-105":59,"doc-detail-456729-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","marked-reversibility-of-functional-small-airway-disease-following-reduction-of-hazardous-inhalational-exposure-a-prm-ct-case-report","Marked Reversibility of Functional Small Airway Disease Following Reduction of Hazardous Inhalational Exposure - A PRM CT Case Report","","We report a clinical case demonstrating how parametric response mapping (PRM) detects and tracks functional small airway disease (SAD) linked to occupational inhalational exposure. A 52-year-old lifelong never-smoker with long-term exposure to metal cutting-fluid fumes and particles presented with exertional dyspnea and moderate airflow obstruction. PRM CT showed PRM-functional SAD (15.7%) and minimal emphysema (0.2%). After increased unprotected exposure, PRM-fSAD rose while spirometry stayed stable, then decreased substantially after exposure reduction and consistent mask use, with symptom and functional improvement. The case supports PRM as an imaging biomarker for early exposure-related SAD and suggests reversibility with timely intervention.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":35,"@type":76,"position":81},"https://docshare.wps.com/document/healthcare/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/marked-reversibility-of-functional-small-airway-disease-following-reduction-of-hazardous-inhalational-exposure-a-prm-ct-case-report/456729/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/marked-reversibility-of-functional-small-airway-disease-following-reduction-of-hazardous-inhalational-exposure-a-prm-ct-case-report/456729.png","ImageObject",300,407,{"name":92,"@type":93},"Finn","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-11-07","2026-09-30",true,{"@type":102,"interactionType":103,"userInteractionCount":34},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What role does parametric response mapping (PRM) play in this case?","Question",{"text":112,"@type":113},"PRM CT is used to detect and monitor functional small airway disease related to occupational inhalational exposure, distinguishing PRM-functional small airway disease from emphysema.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How did the patient’s PRM-fSAD change after increased exposure?",{"text":117,"@type":113},"After 1.5 years of increased unprotected exposure, PRM-fSAD increased markedly (from 15.7% to 46.2%) even though spirometry remained stable.",{"name":119,"@type":110,"acceptedAnswer":120},"What intervention led to improvement in PRM-fSAD?",{"text":121,"@type":113},"Workload reduction and consistent mask use reduced PRM-fSAD to 2.8%, accompanied by symptomatic and functional improvement.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},456729,1790820558,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":34,"category_name":35,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":34,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":19,"language":139,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":67,"update_tm":143,"read_time":52,"preview_page_count":4},34359740700684,"https://ap-avatar.wpscdn.com/avatar/1f400023980c374ae676?_k=1777273430885731487","Respirology Case Reports  \nCASE REPORT  OPEN ACCESS   \nMarked Reversibility of Functional Small Airway Disease Following Reduction of Hazardous Inhalational Exposure:  \nA PRM CT Case Report  \nYeun Ho Lee1 | Yunjoo Im2 | Sun Hye Shin3 | Ho Yun Lee4,5 | Hye Yun Park3,6   \n1Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea | 2Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University College of Medicine, Seoul, South Korea | 3Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea | 4Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea | 5Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul, South Korea | 6Department of Clinical Research and Evaluation, Samsung Advanced Institute for Health Sciences and  \nTechnology, Sungkyunkwan University, Seoul, South Korea Correspondence: Hye Yun Park ([hyeyunpark@skku.edu](hyeyunpark@skku.edu))  \nReceived: 10 September 2025 | Revised: 30 November 2025 | Accepted: 5 December 2025  \nAssociate Editor: Arata Azuma  \nKeywords: chronic obstructive pulmonary disease | fume exposure | occupational lung disease | parametric response mapping | small airway disease  \nABSTRACT  \nWe report a case illustrating the role of parametric response mapping (PRM) in detecting and monitoring small airway disease (SAD) related to occupational inhalational exposure. A 52-year-old woman, a lifelong never-smoker with chronic occupational exposure to metal cutting-fluid fumes and metal particles, presented with exertional dyspnea and moderate airflow obstruction. PRM CT revealed PRM-functional small airway disease (PRM-fSAD) of 15.7% and PRM-emphysema of 0.2% . After 1.5 years of increased unprotected exposure, PRM-fSAD rose to 46.2%, with stable spirometry but reduced diffusing capacity and more frequent exacerbations. Following workload reduction and consistent mask use, PRM-fSAD decreased to 2.8% accompanied by symptomatic and functional improvement. This case supports PRM as a reliable imaging biomarker for early detection of exposure-related SAD, even before spirometric decline, and highlights the potential reversibility of occupational lung injury with timely intervention.  \n1 | Introduction  \nChronic obstructive pulmonary disease (COPD) is a heterogeneous condition characterized by varying degrees of small airway disease (SAD) and emphysema, which may progress at different rates despite similar degrees of airflow limitation [1] . Disease progression has traditionally been assessed by spirometric decline, particularly in forced expiratory volume in 1 s (FEV1), but this single measure does not fully capture disease  \ncomplexity. With increasing use of chest computed tomography (CT), quantitative imaging biomarkers have emerged as complementary tools for evaluating status and predicting progression.  \nParametric response mapping (PRM) is a voxel-based technique that uses paired inspiratory and expiratory CT scans to distinguish normal lung, functional small airway disease (PRM– fSAD), and emphysema (PRM-emphysema) [2] . PRM enables spatial localization and quantification of disease components  \n\n| Yeun Ho Lee and Yunjoo Im contributed equally to this work as first authors. |\n| --- |\n| This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.\u003Cbr>© 2026 The Author(s). Respirology Case Reports published by John Wiley & Sons Australia, Ltd on behalf of The Asian Pacific Society","cbCaipvN16Z7ZiSq","https://ap.wps.com/l/cbCaipvN16Z7ZiSq","pdf",802518,"English","# Abstract\n# Introduction\n# Case Report","[{\"question\":\"What role does parametric response mapping (PRM) play in this case?\",\"answer\":\"PRM CT is used to detect and monitor functional small airway disease related to occupational inhalational exposure, distinguishing PRM-functional small airway disease from emphysema.\"},{\"question\":\"How did the patient’s PRM-fSAD change after increased exposure?\",\"answer\":\"After 1.5 years of increased unprotected exposure, PRM-fSAD increased markedly (from 15.7% to 46.2%) even though spirometry remained stable.\"},{\"question\":\"What intervention led to improvement in PRM-fSAD?\",\"answer\":\"Workload reduction and consistent mask use reduced PRM-fSAD to 2.8%, accompanied by symptomatic and functional improvement.\"}]","Marked Reversibility of Functional Small Airway Disease Following Reduction of Hazardous Inhalational Exposure - A PRM CT Case Report | PDF",1790746797]