title: Quantitative CT indexes are significantly associated with exercise oxygen desaturation in interstitial lung disease related to systemic sclerosis.
abstract: BACKGROUND
  Interstitial Lung Disease (ILD) is the first cause of death related to Systemic Sclerosis (SSc). The ILD severity can be assessed with clinical, functional and radiological outcome. Nevertheless none of them is completely validated in clinical practice. Recently a new radiological evaluation based on Quantitative Computed Tomography Indexes (QCTI) was proposed on the basis of voxel-wise quantitative analysis of chest CT.
  
  
  OBJECTIVE
  The main aim of this study is to verify if QCTI can identify SSc patients with significant oxygen desaturation during the 6 min walking test. The discrimination performance of QCTI and the other clinical, functional and radiological outcomes was also investigated.
  
  
  METHODS
  Sixty three SSc patients were enrolled and underwent clinical, functional and radiological assessment. Inspiratory chest CT of each patient was evaluated with both a visual score and a dedicated software for segmentation of the lung in order to obtained QCTI.
  
  
  RESULTS
  Patients with or without severe oxygen desaturation showed different QCTI, CT visual score and functional outcomes (P < 0.05). In particular, QCTI and functional outcomes showed almost the same discriminating ability.
  
  
  CONCLUSIONS
  QCTI detect SSc patients with a severe oxygen desaturation after exercise as well as functional and other radiological outcomes. It is remarkable that QCTI are the only outcome without intra- or inter-reader variability because they are obtained with an algorithm. These findings bring out the QCTI as a concrete tool in SSc-ILD assessment.
authors.affiliation: Department of Medicine, Internal Medicine and Rheumatology Unit, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy.
authors.forename: Alarico
authors.initials: A
authors.lastname: Ariani
authors.affiliation: Department of Clinical & Experimental Medicine, Respiratory Disease and Lung Function Unit, University of Parma, Parma, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Aiello
authors.affiliation: Department of Clinical Sciences, Section of Radiology, University of Parma, Parma, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Silva
authors.affiliation: Department of Clinical & Experimental Medicine, Respiratory Disease and Lung Function Unit, University of Parma, Parma, Italy.
authors.forename: Veronica
authors.initials: V
authors.lastname: Alfieri
authors.affiliation: Department of Clinical & Experimental Medicine, Respiratory Disease and Lung Function Unit, University of Parma, Parma, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Bonati
authors.affiliation: Department of Medicine, Internal Medicine and Rheumatology Unit, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Lumetti
authors.affiliation: Department of Medicine, Internal Medicine and Rheumatology Unit, Azienda Ospedaliero-Universitaria di Parma, Parma, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Delsante
authors.affiliation: Department of Clinical Sciences, Section of Radiology, University of Parma, Parma, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Sverzellati
authors.affiliation: Department of Clinical & Experimental Medicine, Respiratory Disease and Lung Function Unit, University of Parma, Parma, Italy.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Chetta
mesh_terms: D000368:Aged; D000465:Algorithms; D005260:Female; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D017563:Lung Diseases, Interstitial / Q000150:complications / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010100:Oxygen / Q000378:metabolism; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000295:instrumentation*; D012595:Scleroderma, Systemic / Q000150:complications / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000503:physiopathology; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*; D000070857:Walk Test / Q000379:methods
chemical_list: D010100:Oxygen
keywords: computer assisted radiographic image interpretation - interstitial lung disease - oxygen deficiency - systemic sclerosis