title: Head to head comparison between the conventional balloon occlusion method and the non-occlusion method for optical coherence tomography.
abstract: BACKGROUND
  Optical coherence tomography (OCT) has been introduced as a high-resolution imaging modality for the coronary arteries. The current OCT system, however, has a serious limitation in that the image acquisition method requires a soft balloon occlusion to avoid signal scattering from red blood cells.
  
  
  OBJECTIVE
  The purpose of this study was to compare OCT images from the conventional balloon occlusion method and a non-occlusion image acquisition method, the continuous-flushing method, in the clinical setting.
  
  
  METHODS
  OCT was performed with the conventional balloon occlusion method and the continuous-flushing method sequentially in 23 patients with stable angina. The image quality and quantitative measurements of OCT images were directly compared between the two methods.
  
  
  RESULTS
  There were no adverse events related to the OCT procedure in any patients. There were no changes in systolic blood pressure and heart rate during the OCT procedure. ST-segment elevation (>2 mm) was recorded in 22 of 23 (96%) patients with the balloon occlusion method, but it was only observed in 1 of 23 (4%) patients with the continuous-flushing method (p<0.01). There were no differences in the visible length (the balloon occlusion method 28.6±2.3 mm vs. the continuous-flushing method 29.2±1.6 mm, p=0.49), image quality, or quantitative measurements between the two methods.
  
  
  CONCLUSIONS
  OCT imaging with the continuous-flushing method could be performed safely and obtained similar quality images compared with the balloon occlusion method. OCT can be used to observe the proximal site of coronary arteries with this new technique.
authors: Department of Cardiovascular Medicine, Wakayama Medical University, Wakayama, Japan.
authors: Hideaki
authors: H
authors: Kataiwa
authors: Atsushi
authors: A
authors: Tanaka
authors: Hironori
authors: H
authors: Kitabata
authors: Hiroki
authors: H
authors: Matsumoto
authors: Manabu
authors: M
authors: Kashiwagi
authors: Akio
authors: A
authors: Kuroi
authors: Hideyuki
authors: H
authors: Ikejima
authors: Hiroto
authors: H
authors: Tsujioka
authors: Keishi
authors: K
authors: Okochi
authors: Takashi
authors: T
authors: Tanimoto
authors: Takashi
authors: T
authors: Yamano
authors: Shigeho
authors: S
authors: Takarada
authors: Nobuo
authors: N
authors: Nakamura
authors: Takashi
authors: T
authors: Kubo
authors: Masato
authors: M
authors: Mizukoshi
authors: Kumiko
authors: K
authors: Hirata
authors: Toshio
authors: T
authors: Imanishi
authors: Takashi
authors: T
authors: Akasaka
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000473:pathology*; D021721:Balloon Occlusion / Q000009:adverse effects / Q000379:methods*; D001794:Blood Pressure; D057791:Cardiac Imaging Techniques / Q000009:adverse effects / Q000379:methods; D003331:Coronary Vessels / Q000473:pathology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D041623:Tomography, Optical Coherence / Q000009:adverse effects / Q000379:methods*