| Title: | A New PET Scanner with Semiconductor Detectors Enables Better Identification of Intratumoral Inhomogeneity |
| Authors: | Shiga, Tohru Browse this author |
| Morimoto, Yuichi Browse this author |
| Kubo, Naoki Browse this author |
| Katoh, Noriko Browse this author |
| Katoh, Chietsugu Browse this author |
| Takeuchi, Wataru Browse this author |
| Usui, Reiko Browse this author |
| Hirata, Kenji Browse this author |
| Kojima, Shinichi Browse this author |
| Umegaki, Kikuo Browse this author |
| Shirato, Hiroki Browse this author |
| Tamaki, Nagara Browse this author |
| Keywords: | oncology |
| PET |
| semiconductor |
| intratumoral heterogeneity |
| Issue Date: | 2009 |
| Publisher: | Society of Nuclear Medicine |
| Journal Title: | Journal of Nuclear Medicine |
| Volume: | 50 |
| Issue: | 1 |
| Start Page: | 148 |
| End Page: | 155 |
| Publisher DOI: | 10.2967/jnumed.108.054833 |
| PMID: | 19091886 |
| Abstract: | An autoradiography method revealed intratumoral inhomogeneity in various solid tumors. It is becoming increasingly important to estimate intratumoral inhomogeneity. However, with low spatial resolution and high scatter noise, it is difficult to detect intratumoral inhomogeneity in clinical settings. We developed a new PET system with CdTe semiconductor detectors to provide images with high spatial resolution and low scatter noise. Both phantom images and patients’ images were analyzed to evaluate intratumoral inhomogeneity. Methods: This study was performed with a cold spot phantom that had 6-mm-diameter cold sphenoid defects, a dual-cylinder phantom with an adjusted concentration of 1:2, and an ''H''-shaped hot phantom. These were surrounded with water. Phantom images and 18F-FDG PET images of patients with nasopharyngeal cancer were compared with conventional bismuth germanate PET images. Profile curves for the phantoms were measured as peak-to-valley ratios to define contrast. Intratumoral inhomogeneity and tumor edge sharpness were evaluated on the images of the patients. Results: The contrast obtained with the semiconductor PET scanner (1.53) was 28% higher than that obtained with the conventional scanner (1.20) for the 6-mm-diameter cold sphenoid phantom. The contrast obtained with the semiconductor PET scanner (1.43) was 27% higher than that obtained with the conventional scanner (1.13) for the dual-cylinder phantom. Similarly, the 2-mm cold region between 1-mm hot rods was identified only by the new PET scanner and not by the conventional scanner. The new PET scanner identified intratumoral inhomogeneity in more detail than the conventional scanner in 6 of 10 patients. The tumor edge was sharper on the images obtained with the new PET scanner than on those obtained with the conventional scanner. Conclusion: These phantom and clinical studies suggested that this new PET scanner has the potential for better identification of intratumoral inhomogeneity, probably because of its high spatial resolution and low scatter noise. |
| Rights: | Reprinted by permission of the Society of Nuclear Medicine |
| Type: | article |
| URI: | http://hdl.handle.net/2115/46753 |
| Appears in Collections: | 医学院・医学研究院 (Graduate School of Medicine / Faculty of Medicine) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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