title: Phase-contrast MRI for detection of mild systemic hemodynamic response after segmental allergen challenge in asthmatic patients.
abstract: OBJECTIVE
  Detection of a systemic hemodynamic response in patients suffering from allergic asthma after segmental endobronchial allergen challenge using phase-contrast magnetic resonance imaging (MRI).
  
  
  METHODS
  Nine asthma patients and four healthy volunteers were examined using MRI (1.5T) before (0 hour), 6 hours, and 24 hours after segmental allergen challenge. Two-dimensional phase-contrast MRI measurements were performed in the aorta (AO) and in the pulmonary artery (PA). In addition, short-axis balanced steady state free precession cardiac cine MRI was performed. Maximum systolic flow, maximum flow acceleration, acceleration volume, acceleration time, distensibility, ejection fraction, stroke volume, end-systolic/diastolic volume, cardiac mass, heart rate (HR), and cardiac output (CO) were determined. Spirometry and bronchoalveolar lavage were also performed.
  
  
  RESULTS
  In patients with asthma, maximal systolic flow and maximal flow acceleration increased 6 hours after provocation in the AO (112.3% and 118.9%, respectively) and PA (113.9% and 116.0%, respectively) compared to baseline (100%, P < .05). HR and CO increased significantly at 6 hours (115% and 118%, respectively) compared to baseline (100%, P = .003). In healthy subjects, almost all MRI-derived hemodynamic parameters did not significantly change at 6 hours and were significantly lower than baseline values at 24 hours (P < .02). Twenty-four hours after allergen challenge, all MRI-derived flow parameters were significantly lower in the control group compared to the asthma group (P < .05). HR, CO, and cardiac function parameters measured at 24 hours showed no significant difference comparing the two groups (P > .05).
  
  
  CONCLUSIONS
  In asthmatic patients, MRI-derived hemodynamic parameters using phase-contrast MRI are slightly altered after segmental allergen provocation compared to normal controls indicating a mild systemic reaction to local allergen challenge.
authors.affiliation: Institute of Interventional Radiology, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, OE 8220, Carl-Neuberg-Str. 1, 30625 Hannover, Germany. Electronic address: hinrichs.jan@mh-hannover.de.
authors.forename: Jan
authors.initials: J
authors.lastname: Hinrichs
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Schaumann
authors.affiliation: Institute of Interventional Radiology, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, OE 8220, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Julius
authors.initials: J
authors.lastname: Renne
authors.affiliation: Institute of Interventional Radiology, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, OE 8220, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Schönfeld
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Faulenbach
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Winkler
authors.affiliation: Institute of Interventional Radiology, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, OE 8220, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Marcel
authors.initials: M
authors.lastname: Gutberlet
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Krug
authors.affiliation: Institute of Interventional Radiology, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, OE 8220, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Wacker
authors.affiliation: Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany; Department of Respiratory Medicine, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, Hannover, Germany.
authors.forename: Jens M
authors.initials: JM
authors.lastname: Hohlfeld
authors.affiliation: Institute of Interventional Radiology, Hannover Medical School, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research, OE 8220, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Vogel-Claussen
mesh_terms: D000328:Adult; D000465:Algorithms; D000485:Allergens; D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology*; D001783:Blood Flow Velocity; D001985:Bronchial Provocation Tests / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011652:Pulmonary Circulation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000485:Allergens
keywords: Phase-contrast MRI; asthma bronchiale; endobronchial allergen challenge