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Portrait of Les R. Folio
Les R. Folio, DO, MPH, MSc (Rad), MAS

Senior Research Physician
Lead Radiologist, Computed Tomography

Radiology and Imaging Sciences

RT, Crozier Chester Medical Center
BSRT, Widener University
MPH, University of California, Berkeley
MSc (Rad), Osteopathic Medical Center of Philadelphia
MAS, Embry Riddle Aeronautical University
DO, Philadelphia College of Osteopathic Medicine

Clinical Professor (adjunct):
George Washington University School of Medicine and Health Sciences


Portrait of Les R. Folio
Les R. Folio, DO, MPH, MSc (Rad), MAS

Senior Research Physician
Lead Radiologist, Computed Tomography

Radiology and Imaging Sciences

RT, Crozier Chester Medical Center
BSRT, Widener University
MPH, University of California, Berkeley
MSc (Rad), Osteopathic Medical Center of Philadelphia
MAS, Embry Riddle Aeronautical University
DO, Philadelphia College of Osteopathic Medicine

Clinical Professor (adjunct):
George Washington University School of Medicine and Health Sciences


Dr. Les R. Folio is a Senior Research Physician and the lead radiologist for Computed Tomography (CT) in Radiology and Imaging Sciences at the NIH Clinical Center.

Dr. Folio is board certified in Diagnostic Radiology by the American Osteopathic Board of Radiology. He completed his MPH at University of California Berkeley. He is a Fellow of both the Society of Advanced Body Imaging (SABI) and the American Osteopathic College of Radiology (AOCR).

Dr. Folio is a retired Colonel with 20 years of military service in the United States Air Force. He served as chief of radiology departments and as commanding officer in military hospitals in the United States, Europe, South East Asia and the Middle East, including two tours of combat duty in Iraq. His assignments include Walter Reed Army Medical Center, Uniformed Services University (as billeted associate professor) and the Pentagon (as an innovative leader in science and technology). In addition to radiology, Dr. Folio trained and practiced in Occupational, Preventive and Aerospace Medicine, and served as a flight surgeon with over 25 combat and combat support missions. He was selected twice by the Air Force as an astronaut nominee and a recipient of the Defense Meritorious Service Medal upon retirement.

Dr. Folio joined NIH in 2009. During his first years as lead radiologist for CT, he oversaw the planning and workflow optimization of the CT department renovation; resulting in a modern, spacious CT section with drastically improved patient staging areas and efficient sight lines for optimal workflow. He also overhauled hundreds of technical CT protocols resulting in significantly reduced radiation exposures to patients to the point of a chest CT delivering a radiation exposure similar to a chest x-ray that he first presented in the US in 2015.

Dr. Folio ‘s clinical research interests range from interactive multimedia quantitative reporting in metastatic disease burden assessment to advanced artificial intelligence/machine learning approaches in oncologic and infectious disease imaging including TB and COVID pneumonia.

Dr. Folio is passionate about leveraging technology to advance medicine. He pioneered the clinical use of multimedia interactive content reporting in radiology that optimize radiologist report value, the quintessential component of diagnostic imaging. The resultant interactive reports have enriched content with three-fold improved concordance with oncologists’ records used to determine therapeutic response, while improving efficiency made possible by extraction of tumor measurement data; negating handwriting and duplicate efforts. Dr. Folio leveraged industry partnership with NIH through research agreements valued at over $1M to achieve this goal. His efforts earned him the NIH Clinical Directors awards for CT radiation exposure monitoring, dose reduction and CT workflow/policy development.

Dr. Folio has published over 120 articles in peer reviewed journals; most recently related to automated quantification in cancer trials including volumetric assessment and several recent publications related to artificial intelligence (AI) and pattern recognition on x-ray and CT. He authored five medical textbooks including an algorithmic approach to chest imaging that guide data scientists to improve machine learning training, and “Combat Radiology” sharing his experiences chairing a radiology department in one of the busiest military hospitals during combat. He holds two issued patents, a CT post-processing algorithm and an upright angle portable chest x-ray marker. He was a co-investigator with the National Library of Medicine leading to a Health and Human Services Ignite Award for Automatic X-Ray Screening for TB in Rural Areas. Dr. Folio is an internationally renowned presenter and keynote speaker at numerous national and international medical conferences. In 2017, AOCR awarded him the Dr. Floyd J. Trenery Memorial Medal for his outstanding service to the AOCR didactic educational program.

Dr. Folio is an Adjunct Clinical Professor of Radiology at the George Washington University School of Medicine and Health Sciences. He co-chairs the Society for Imaging Informatics in Medicine (SIIM) hackathon committee, and the international HIMSS (Healthcare Information and Management Systems Society)-SIIM multimedia interactive content reporting workgroup.  He also serves as the fellowship nomination committee chair for the Society of Advanced Body Imaging (SABI).

Visit Dr. Folio’s Bibliography.

Relating to tumor assessment informatics/imaging

Analyzing inter-reader variability affecting deep ensemble learning for COVID-19 detection in chest radiographs. Rajaraman S, Sornapudi S, Alderson PO, Folio LR, Antani SK (Nov 2020)  PLoS ONE 15(11): e0242301. External Link Icon

Iteratively Pruned Deep Learning Ensembles for COVID-19 Detection in Chest X-rays. Rajaraman S, Siegelman J, Alderson PO, Folio LS, Folio LR, Antani SK. IEEE Access. 2020;8:115041-115050. doi: 10.1109/access.2020.3003810. Epub 2020 Jun 19. PMID: 32742893

Web-based Conferencing: Tips, Tricks and Scenario-Based Best Practices for Clinicians During a Pandemic Crisis.  Catanzano TC, Sadhna S, Folio LR. 7/8 2020 - Volume 44 - Issue 4 - p 465-471 doi: 10.1097/RCT.0000000000001072

Cabozantinib in patients with platinum-refractory metastatic urothelial carcinoma: an open-label, single-centre, phase 2 trial. Apolo AB, Nadal R, Tomita Y, Davarpanah NN, Cordes LM, Steinberg SM, Cao L, Parnes HL, Costello R, Merino MJ, Folio LR, Lindenberg L, Raffeld M, Lin J, Lee MJ, Lee S, Alarcon SV, Yuno A, Dawson NA, Allette K, Roy A, De Silva D, Lee MM, Sissung TM, Figg WD, Agarwal PK, Wright JJ, Ning YM, Gulley JL, Dahut WL, Bottaro DP, Trepel JB. Lancet Oncol. 2020 Aug;21(8):1099-1109. Doi: 10.1016/S1470-2045(20)30202-3. Epub 2020 Jul 6. PMID: 32645282

Pulmonary Function in Patients With Multiple Endocrine Neoplasia 2B. Fuller S, Del Rivero J, Venzon D, Ilanchezhian M, Allen D, Folio L, Ling A, Widemann B, Fontana JR, Glod J. J Clin Endocrinol Metab. 2020 Sep 1;105(9):2919-28. doi: 10.1210/clinem/dgaa296. PMID: 32448901

Preparing Medical Imaging Data for Machine Learning. Willemink MJ, Koszek WA, Hardell C, Wu J, Fleischmann D, Harvey H, Folio LR, Summers RM, Rubin DL, Lungren MP. Radiology. 2020 Apr;295(1):4-15. doi: 10.1148/radiol.2020192224 Epub 2020 Feb 18. External Link Icon

Augmented Radiologist Workflow Improves Report Value and Saves Time: A Potential Model for Implementation of Artificial Intelligence. Do HM, Spear LG, Nikpanah M, Mirmomen SM, Machado LB, Toscano AP, Turkbey B, Bagheri MH, Gulley JL, Folio LR. Acad Radiol. 2020 Jan;27(1):96-105.

Defective glycosylation and multisystem abnormalities characterize the primary immunodeficiency XMEN disease. Ravell JC, Folio LR, Lenardo MJ.  J Clin Invest. 2020 Jan 2;130(1):507-522. doi: 10.1172/JCI131116. PubMed PMID: 31714901; PubMed Central PMCID: PMC6934229.

Multimedia-enhanced Radiology Reports: Concept, Components, and Challenges. Folio LR, Machado LB, Dwyer AJ. Radiographics. 2018 Mar-Apr;38(2):462-482. doi: 10.1148/rg.2017170047. Review. PubMed PMID: 29528822; PubMed Central PMCID: PMC5881644.

Radiology Reports With Hyperlinks Improve Target Lesion Selection and Measurement Concordance in Cancer Trials. Machado LB, Apolo AB, Steinberg SM, Folio LR. AJR. American journal of roentgenology. 2017; 208(2):W31-

ENABLE (Exportable Notation and Bookmark List Engine): an Interface to Manage Tumor Measurement Data from PACS to Cancer Databases. Goyal N, Apolo AB, Berman ED, Bagheri MH, Levine JE, Glod JW, Kaplan RN, Machado LB, Folio LR. Journal of digital imaging. 2017 Jan;W37.

Clinical Applications of a CT Window Blending Algorithm: RADIO (Relative Attenuation-Dependent Image Overlay). Mandell JC, Khurana B, Folio LR, Hyun H, Smith SE, Dunne RM, Andriole KP. Journal of digital imaging. 2017 Jan.

Quantitative Radiology Reporting and Tumor Metrics: Survey of Oncologists and Radiologists. L Folio, Nelson C, Benjamin M, Ran A, Englehard G, Bluemke D. American Journal of Roentgenology. 2015 Sep;205(3):W233-43.

Docetaxel Alone or in Combination with a Therapeutic Cancer Vaccine (PANVAC) in Patients With Metastatic Breast Cancer: A Randomized Clinical Trial. Heery CR, Ibrahim NK, Arlen PM, Mohebtash M, Murray JL, Koenig K, Madan RA, McMahon S, Marté JL, Steinberg SM, Donahue RN, Grenga I, Jochems C, Farsaci B, Folio LR, Schlom J, Gulley JL. JAMA Oncol. 2015 Nov 1;1(8):1087-95.

Viable tumor volume: Volume of interest within segmented metastatic lesions, a pilot study of proposed computed tomography response criteria for urothelial cancer. L.R. Folio, Turkbey E, Steinberg S, Apolo A. Eur J Radiol (2015).

Consistency and Efficiency of CT Analysis of Metastatic Disease: Semiautomated Lesion Management Application Within a PACS. Folio LR, Sandouk A, Huang J, Solomon JM, Apolo AB. AJR Am J Roentgenol. 2013 Sep;201(3):618-25.

Automated Registration, Segmentation and Measurement of Metastatic Melanoma Tumors in Serial CT Scans. Folio L, Choi M, Solomon J, Schaub NP. Acad Radiol. 2013 May;20(5):604-13.

Relating to infectious disease diagnosis, procedures and prevention

Radiology Preparedness in Ebola Virus Disease. Guidelines and Challenges for Disinfection of Medical Imaging Equipment for the Protection of Staff and Patients. Mollura D, Folio L, Palmore T, Bluemke D. Radiology 2015 Feb 5:142670.

Aspergillus tanneri sp. nov., a new pathogen that causes invasive disease refractory to antifungal therapy. Sugui JA, Peterson SW, Clark LP, Nardone G, Folio L, Riedlinger G, Zerbe CS, Shea Y, Henderson CM, Zelazny AM, Holland SM, Kwon-Chung KJ. J Clin Microbiol. 2012 Oct;50(10):3309-17.

Folio LR, Yao E. "US Military Smallpox Vaccination Program." J Am Osteopath Assoc. 2007 Dec;107(12):547-553

Hanson EH, Neimeyer DM, Folio LR, et al. "Potential Use of Microarray Technology For Rapid Identification of Central Nervous System Pathogens." Military Medicine. 2004 Aug;169(8):594-9.

Folio LR, Lahti RL, Cockrum DS, Bills S, Younker MR. "Initial Experience with Mass Immunization as a Bioterrorism Countermeasure." J Am Osteopath Assoc. 2004 Jun;104(6):240-3.

Relating to automation of TB in rural countries

Atlas-based Rib-bone detection in Chest X-rays. Candemir S, Folio L, Computerized Medical Imaging and Graphics. Available online 13 April 2016

Combination of texture and shape features to detect pulmonary abnormalities in digital chest X-rays. Karargyris A, Folio L, Thoma GR. Int J Comput Assist Radiol Surg. 2015 Jun 20.

Automatic tuberculosis screening using chest radiographs. Jaeger S, Karargyris A, Candemir S, Folio L, Siegelman J, Callaghan F, Zhiyun Xue, Palaniappan K, Singh RK, Antani S, Thoma G, Yi-Xiang Wang, Pu-Xuan Lu, McDonald CJ. IEEE Trans Med Imaging. 2014 Feb;33(2):233-45.

Automatic screening for tuberculosis in chest radiographs: a survey. Jaeger S, Karargyris A, Candemir S, Siegelman J, Folio L, Antani S, Thoma G. Quant Imaging Med Surg. 2013 Apr;3(2):89-99.

Relating to non-tuberculous mycobacteria disease

Mortality among patients with pulmonary non-tuberculous mycobacteria disease Fleshner M, Olivier KN, Shaw PA, Adjemian J, Strollo S, Claypool RJ, Folio L, Zelazny A, Holland SM, Prevots DR.. Int J Tuberc Lung Dis. 2016 May;20(5):582-7.

Inhaled amikacin for treatment of refractory pulmonary nontuberculous mycobacterial disease. Olivier KN, Shaw PA, Glaser TS, Bhattacharyya D, Fleshner M, Brewer CC, Zalewski CK, Folio LR, Siegelman JR, Shallom S, Park IK, Sampaio EP, Zelazny AM, Holland SM, Prevots DR.Ann Am Thorac Soc. 2014 Jan;11(1):30-5. doi: 10.1513/AnnalsATS.201307-231OC.

Lung manifestations in an autopsy-based series of pulmonary or disseminated nontuberculous mycobacterial disease. O'Connell ML, Birkenkamp KE, Kleiner DE, Folio LR, Holland SM, Olivier KN. Chest. 2012 May;141(5):1203-9.

Relating to imaging findings in genetically defined diseases

Immune dysregulation in human subjects with heterozygous germline mutations in CTLA4. Kuehn HS, et. al., Folio LR, Uzel G. Science. 2014 Sep 11.

Dominant-activating germline mutations in the gene encoding the PI(3)K catalytic subunit p110δ result in T cell senescence and human immunodeficiency. Lucas CL, Folio LR, Uzel G. Nat Immunol. 2014 Jan;15(1):88-97.

Natural history of Autoimmune Lymphoproliferative Syndrome associated with FAS gene mutations. Price S, Folio LR, Rao VK, Lenardo MJ. Blood. Blood. 2014 Jan 7.

Germline Mutation in Phosphoinoisitide 3-Kinase p110s Cause T Cell Senescence and Human Immunodeficiency. Lucas CL, et al. Folio LR, Uzel G. Dominant-Activating. Nature Oct 2013.

Other select publications

Opportunities to Reduce CT Radiation Exposure, Experience Over 5 Years at the NIH Clinical Center. Kovacs WC, Yao J, Bluemke DA, Folio LR. Radiation protection dosimetry. 2017 Jan.

Abdominal Imaging with Contrast-enhanced Photon-counting CT: First Human Experience. Pourmorteza A, Symons R, Sandfort V, Mallek M, Fuld MK, Henderson G, Jones EC, Malayeri AA, Folio LR, Bluemke DA. Radiology. 2016 Feb.

Segmentation and Image Analysis of Abnormal Lungs in Computed Tomography: Current Approaches, Challenges, and Future Trends. Mansoor A, Bagci U, Foster B, Xu Z, Papadakis GZ, Folio LR, Udupa JK, Mollura DJ. Radiographics. 2015 Jul-Aug;35(4):1056-76. Radiographics (Cover Article).

Ballistic Wound Path Identification and Trajectory Analysis on Anatomic Ballistic Computerized Tomography Phantoms. Folio L, Fischer T, Shogan P, Frew M, Bunger R, Provenzale J. Radiology. Mar;258(3):923-9. Epub 2011 Jan 11. Results of this article featured on Discovery Channel Canada in May 2011.

  • Health and Human Services Ignite Award for Automatic X-Ray Screening for Rural Areas, Co-investigator, 2015
  • Clinical Director Award for CT exposure monitoring, reduction and CT workflow/ policy development
  • Trenery Medal, one of the highest awards bestowed by his professional society, the American Osteopathic College of Radiology, 2017
  • Military awards include:
    • Defense Meritorious Service Medal
    • Meritorious Service Medals
    • Aerial Achievement Medals
    • Humanitarian Service Medal
    • Southwest Asia Service Medal
    • Korean service Medal
    • National Defense Medal
    • Army Commendation Medal
    • Air Force Commendation Medal
    • Air Force Achievement Medal
    • Expert Marksmanship
    • Air Force Outstanding Unit Award (with Valor)
  • Patents issued:
    • UpRite: A method and apparatus for measuring inclination of Portable Chest X-Rays. Patent # 9,541,822
    • Multigrayscale Overlay Window: Universal CT Window for CT Triage in combat trauma, mass casualty incidents and imaging cancer. Patent # 8,406,493

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This page last updated on 05/17/2021

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