Photomultiplier Tube Artifacts on 67Ga-Citrate Imaging Caused by Loss of Correction Floods Due to an Off-Peak Status of One Head of a Dual-Head γ-Camera

Journal of Nuclear Medicine Technology

Na Song¹  Ruth Lorenzo¹  Charito Love¹  Sridivya Jaini¹  Joseph E. Glaser¹ 

关键词: gamma camera;    scintigraphy;    quality control;    electronic off-peak;    artifact;    gallium;   

DOI  :  10.2967/jnmt.111.097246

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

γ-cameras use flood-field corrections to ensure image uniformity during clinical imaging. A loss or corruption of the correction data of one head of a dual-head camera can result in an off-peak artifactual appearance. We present our experience with the occurrence of such an incident on a 67Ga scan. Methods: A patient was referred for a whole-body 67Ga scan to evaluate for causes of neutropenic fever. Whole-body planar and static images of the head, chest, abdomen, pelvis, and lower extremities in multiple projections were obtained. Results: Whole-body images showed decreased image quality on the anterior view obtained with detector 1 and an unremarkable posterior image obtained with detector 2. A problem with detector 2 was suspected, and additional static images were obtained after rotation of the detector heads. The posterior images taken with detector 1 showed photomultiplier tube outlines. The anterior images taken with detector 2 showed improved count and image quality. It was later found that the uniformity map for detector 2 had been lost and that this software malfunction led to the resulting imaging problem. Conclusion: When artifacts with an off-peak appearance are seen on scintigraphic images, evaluation of possible causes should include not only isotope window settings but also an incorrect or corrupted uniformity map.

【 授权许可】

Unknown