A new collimator for I-123-IMP SPECT imaging of the brain

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:6919464

Oyamada, H; Fukukita, H; Tanaka, E; Shibahara, N; Kawai, H; Terui, S

At present, commercially available I-123-IMP is contaminated with I-124 and its concentration on the assay date is said to be approximately 5%. Therefore, the application of medium energy parallel hole collimator (MEPC) used in many places for SPECT results in deterioration of the image quality. Recently, the authors have developed a new collimator for I-123-IMP SPECT imaging comprised of 4 slat type units; ultrahigh resolution (UHR), high resolution (HR), high sensitivity (HS), and ultrahigh sensitivity (UHS). The slit width/septum thickness in mm for UHR, HR, HS, and UHS are 0.9/0.5, 1.5/0.85, 3.2/1.5, and 5.2/2.0, respectively. In practice, either UHR or HR is set to the detector (Shimadzu LFOV-E, modified type) together with either HS or UHS. The former is always set to the detector with the slit direction parallel to the rotation axis, and the latter is set with its slit direction at a right angle to the former. This is based on an idea that, upon sacrifice of resolution to some extent, sensitivity can be gained on the axial direction while the resolution on the transaxial slice will still be sufficiently preserved. Resolutions (transaxial direction/axial direction) in FWHM (mm) for each combination (UHR-HS, UHR-UHS, HR-HS, and HR-UHS) were 15.9/31.4, 15.9/36.5,23.2/33.3, and 23.9/40.7, respectively, whereas the resolution of MEPC was 28.7/29.5. On the other hand, relative sensitivities to MEPC were 0.57, 0.86, 0.80, and 1.16. The authors conclude that the combination of UHR and HS is best suited for clinical practice and, at present they are obtaining I-123-IMP SPECT images of good quality.

• Research Organization: National Cancer Center Hospital, Tokyo
• OSTI ID: 6919464
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

440101* -- Radiation Instrumentation-- General Detectors or Monitors & Radiometric Instruments
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
550601 -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
BETA DECAY RADIOISOTOPES
BODY
BRAIN
CENTRAL NERVOUS SYSTEM
COLLIMATORS
COMPUTERIZED TOMOGRAPHY
COUNTING TECHNIQUES
DESIGN
DIAGNOSTIC TECHNIQUES
ELECTRON CAPTURE RADIOISOTOPES
EMISSION COMPUTED TOMOGRAPHY
HOURS LIVING RADIOISOTOPES
IMAGES
INTERMEDIATE MASS NUCLEI
IODINE 123
IODINE ISOTOPES
ISOTOPES
NERVOUS SYSTEM
NUCLEI
ODD-EVEN NUCLEI
ORGANS
PERFORMANCE
RADIOISOTOPES
RESOLUTION
SENSITIVITY
SEQUENTIAL SCANNING
SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY
TOMOGRAPHY