Comparison of quality of multiplanar reconstructions and direct coronal multidetector CT scans of the lung.
OBJECTIVE
The purpose of this study was to compare the quality of coronal multiplanar reconstructions with the quality of direct coronal thin-section multidetector CT (MDCT) scans.


METHODS
Axial multidetector CT (MDCT) scans were obtained through the entire lung in 10 normal autopsy lung specimens using an MDCT scanner. Four protocols were used: 0.5-mm collimation with a 0.5-mm reconstruction interval; 0.5-mm collimation with a 0.3-mm reconstruction interval; 1-mm collimation with a 0.5-mm reconstruction interval; and 2-mm collimation with a 1-mm reconstruction interval. Multiplanar reconstruction images with 0.5-mm slice thickness were obtained from the four types of data sets. Direct coronal thin-section CT of the same 10 autopsy lung specimens was performed using 0.5-mm scan collimation, a 0.3-mm reconstruction interval, a 25.6-cm field of view, and a 512 x 512 matrix. Two independent observers compared the image quality of each of the four coronal multiplanar reconstruction sets with that of direct coronal thin-section CT scans. The observers analyzed visualization of anatomic features and artifacts.


RESULTS
The total image quality of the multiplanar reconstructions obtained from 0.5-mm collimation data with or without 0.3-mm overlapping reconstruction was equal to that of direct coronal thin-section CT scans in all 20 interpretations. The image quality of multiplanar reconstruction images from 0.5-mm collimation data either with or without overlapping reconstruction was superior to multiplanar reconstruction images obtained from 1- or 2-mm collimation scans (p < 0.01, Fisher's exact test). Stairstep artifacts in multiplanar reconstructions using 0.5-mm collimation without overlapping reconstruction were equal to those with overlapping reconstruction and were fewer than those on 1- or 2-mm collimation (p < 0.01, Mann-Whitney U test).


CONCLUSIONS
The image quality of coronal multiplanar reconstructions from isotropic voxel data obtained using 0.5-mm collimation, with or without overlapping reconstruction, is similar to that of direct coronal thin-section CT scans.
Honda
Osamu
O
Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
Johkoh
Takeshi
T
Yamamoto
Shuji
S
Koyama
Mitsuhiro
M
Tomiyama
Noriyuki
N
Kozuka
Takenori
T
Hamada
Seiki
S
Mihara
Naoki
N
Nakamura
Hironobu
H
Müller
Nestor L
NL
D000368:Aged; D016477:Artifacts; D006801:Humans; D007091:Image Processing, Computer-Assisted; D066298:In Vitro Techniques; D008168:Lung / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D008297:Male; D011856:Radiographic Image Enhancement; D014057:Tomography, X-Ray Computed / Q000379:methods*