title: Validation of prone myocardial perfusion SPECT with a variable-focus collimator versus supine myocardial perfusion SPECT with or without computed tomography-derived attenuation correction.
abstract: OBJECTIVE
  The purpose of this study is to evaluate whether prone myocardial perfusion single-photon emission computed tomography (MPS) with thallium-201 acquired through a variable-focus collimator (IQ-SPECT) can correct for soft-tissue attenuation.
  
  
  METHODS
  Thirty-nine patients underwent thallium-201 stress MPS with IQ-SPECT. Delayed images acquired with the patients in the prone position were compared with delayed images obtained with the patients in the supine position with computed tomography-derived attenuation correction (CTAC) (S-CTAC images) or without CTAC (S-NCTAC images). Quantitative tracer uptake (QTU) and semi-quantitative defect scores were determined for the 17 standard myocardial segments. Segments were categorized into anterior-anteroseptal, lateral, inferior, and apex, and areas with defect decision were determined by using the defect scores.
  
  
  RESULTS
  Image quality in the prone images was similar to that of S-NCTAC and S-CTAC images. In male patients, QTU in prone images was equivalent to that in S-CTAC images in the anterior-anteroseptal area, but was significantly lower than that in S-CTAC images in the inferior area. In female patients, QTU in prone images was similar to that in S-CTAC images in the anterior-anteroseptal, lateral, and inferior areas. In male and in female patients, QTU in the apex was significantly greater in the prone images than that in the S-CTAC images. In the combined male and female patient group, the defect decision for prone images was similar to that for S-CTAC images in the anterior-anteroseptal, lateral, and inferior areas. Apical defects were observed more frequently in S-CTAC images than in prone or S-NCTAC images.
  
  
  CONCLUSIONS
  Fewer artificial defects were observed in the apex of images acquired by prone imaging than by S-CTAC imaging. Prone images improved attenuation and had similar defect decision as S-CTAC images in the anterior-anteroseptal, lateral, and inferior areas.
authors: Department of Cardiology, National Hospital Organization Sagamihara National Hospital, 18-1 Sakuradai, Minami-ku, Sagamihara City, Kanagawa, 252-0392, Japan.
authors: Tomoko
authors: T
authors: Takamura
authors: Department of Cardiology, National Hospital Organization Sagamihara National Hospital, 18-1 Sakuradai, Minami-ku, Sagamihara City, Kanagawa, 252-0392, Japan. dzq04361@nifty.com.
authors: Yoriko
authors: Y
authors: Horiguchi
authors: Department of Cardiology, National Hospital Organization Sagamihara National Hospital, 18-1 Sakuradai, Minami-ku, Sagamihara City, Kanagawa, 252-0392, Japan.
authors: Masahiko
authors: M
authors: Kanna
authors: Department of Cardiology, National Hospital Organization Sagamihara National Hospital, 18-1 Sakuradai, Minami-ku, Sagamihara City, Kanagawa, 252-0392, Japan.
authors: Hirooki
authors: H
authors: Matsushita
authors: Department of Cardiology, National Hospital Organization Sagamihara National Hospital, 18-1 Sakuradai, Minami-ku, Sagamihara City, Kanagawa, 252-0392, Japan.
authors: Yuta
authors: Y
authors: Sudo
authors: Department of Cardiology, National Hospital Organization Sagamihara National Hospital, 18-1 Sakuradai, Minami-ku, Sagamihara City, Kanagawa, 252-0392, Japan.
authors: Shinnosuke
authors: S
authors: Kikuchi
authors: Department of Radiology, National Hospital Organization Sagamihara National Hospital, Kanagawa, Japan.
authors: Tomohiro
authors: T
authors: Ueda
authors: Department of Radiology, National Hospital Organization Sagamihara National Hospital, Kanagawa, Japan.
authors: Ryo
authors: R
authors: Sasaki
authors: Department of Cardiology, National Hospital Organization Sagamihara National Hospital, 18-1 Sakuradai, Minami-ku, Sagamihara City, Kanagawa, 252-0392, Japan.
authors: Yukiko
authors: Y
authors: Morita
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001692:Biological Transport; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D055414:Myocardial Perfusion Imaging / Q000379:methods*; D016684:Prone Position; D016683:Supine Position; D013794:Thallium Radioisotopes / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed
chemical_list: D013794:Thallium Radioisotopes
keywords: CT-derived attenuation correction; IQ-SPECT; Multifocal collimator; Myocardial perfusion imaging; Prone imaging