Usefulness of Ultralow-Dose (Submillisievert) Chest CT Using Iterative Reconstruction for Initial Evaluation of Sharp Fish Bone Esophageal Foreign Body.
OBJECTIVE
The purpose of this article was to evaluate the usefulness of ultralow-dose chest CT as an initial imaging study for evaluation of sharp fish bone esophageal foreign body (FB).


METHODS
A total of 57 subjects who underwent ultralow-dose chest CT were included in this retrospective study. All subjects had a history of ingestion and symptoms of esophageal FB. All ultralow-dose chest CT data were reconstructed twice, once with filtered back projection (FBP) and once with iterative reconstruction, and three observers reviewed the images independently. ROC analysis was used to evaluate diagnostic performance of ultralow-dose chest CT. Intraclass correlation coefficient (ICC) was calculated for analysis of interobserver agreement.


RESULTS
Among 57 patients, 42 were confirmed as having esophageal FB. Significant objective noise reduction of mediastinum was achieved using an iterative reconstruction technique. Subjective image noise of iterative reconstruction was significantly better than that of FBP. Overall diagnostic performance of ultralow-dose chest CT for esophageal FB of iterative reconstruction (AUC = 0.999) was significantly better than that of FBP (AUC = 0.95) (p = 0.02). Interobserver agreement was greater for iterative reconstruction (ICC = 0.944) than for FBP (ICC = 0.778).


CONCLUSIONS
Ultralow-dose chest CT using iterative reconstruction provided satisfactory diagnostic image quality for identifying fish bone esophageal FB with reduced radiation dose and high observer accuracy. Therefore, ultralow-dose chest CT would be adequate as a first-line imaging modality for fish bone esophageal FB.
1 Department of Radiology, Ajou University School of Medicine, 164 Worldcup Rd, Yeongtong-gu, Suwon 443-721, Republic of Korea.
Eun Young
EY
Kim
2 Department of Emergency Medicine, Ajou University School of Medicine, Suwon, Republic of Korea.
Young Gi
YG
Min
3 Department of Radiology, B&B Hospital, Lalitpur, Nepal.
Anjali Basnyat
AB
Bista
1 Department of Radiology, Ajou University School of Medicine, 164 Worldcup Rd, Yeongtong-gu, Suwon 443-721, Republic of Korea.
Kyung Joo
KJ
Park
1 Department of Radiology, Ajou University School of Medicine, 164 Worldcup Rd, Yeongtong-gu, Suwon 443-721, Republic of Korea.
Doo Kyoung
DK
Kang
1 Department of Radiology, Ajou University School of Medicine, 164 Worldcup Rd, Yeongtong-gu, Suwon 443-721, Republic of Korea.
Joo Sung
JS
Sun
D000293:Adolescent; D000328:Adult; D000818:Animals; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D004636:Emergency Service, Hospital; D004947:Esophagus / Q000000981:diagnostic imaging*; D005260:Female; D005399:Fishes; D005547:Foreign Bodies / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted; D013902:Radiography, Thoracic; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
CT; esophagus; filtered back projection; foreign body ingestion; iterative reconstruction