title: Ventilation distribution studies comparing Technegas and "Gallgas" using 68GaCl3 as the label.
abstract: Ventilation distribution can be assessed by SPECT with Technegas. This study was undertaken in piglets with different degrees of ventilation inhomogeneity to compare PET using (68)Ga-labeled pseudogas or "Gallgas" with Technegas.
  
  
  METHODS
  Twelve piglets were studied in 3 groups: control, lobar obstruction, and diffuse airway obstruction. Two more piglets were assessed for lung volume (functional residual capacity).
  
  
  RESULTS
  In controls, SPECT and PET images showed an even distribution of radioactivity. With lobar obstruction, the absence of ventilation of the obstructed lobe was visible with both techniques. In diffuse airway obstruction, SPECT images showed an even distribution of radioactivity, and PET images showed more varied radioactivity over the lung.
  
  
  CONCLUSIONS
  PET provides detailed ventilation distribution images and a better appreciation of ventilation heterogeneity. Gallgas with PET is a promising new diagnostic tool for the assessment of ventilation distribution.
authors.affiliation: Department of Medical Sciences, Clinical Physiology, Uppsala University, Uppsala, Sweden.
authors.forename: João Batista
authors.initials: JB
authors.lastname: Borges
authors.forename: Irina
authors.initials: I
authors.lastname: Velikyan
authors.forename: Bengt
authors.initials: B
authors.lastname: Långström
authors.forename: Jens
authors.initials: J
authors.lastname: Sörensen
authors.forename: Johan
authors.initials: J
authors.lastname: Ulin
authors.forename: Enn
authors.initials: E
authors.lastname: Maripuu
authors.forename: Mattias
authors.initials: M
authors.lastname: Sandström
authors.forename: Charles
authors.initials: C
authors.lastname: Widström
authors.forename: Göran
authors.initials: G
authors.lastname: Hedenstierna
mesh_terms: D000403:Airway Resistance / Q000502:physiology; D000818:Animals; D005708:Gallium; D005710:Gallium Radioisotopes; D008168:Lung / Q000000981:diagnostic imaging*; D008170:Lung Compliance / Q000502:physiology; D016210:Methacholine Chloride; D018721:Muscarinic Agonists; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D015656:Respiratory Mechanics / Q000502:physiology*; D013670:Sodium Pertechnetate Tc 99m; D013552:Swine; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D005710:Gallium Radioisotopes; D018721:Muscarinic Agonists; D019275:Radiopharmaceuticals; D016210:Methacholine Chloride; C056708:Technegas; C034163:gallium chloride; D013670:Sodium Pertechnetate Tc 99m; D005708:Gallium