Lu-177 Dotatate SPECT/CT 검사에서 재구성 조건 변화에 따른 영상 질 평가에 관한 연구

• 영문명: A Study on the Evaluation of Image Quality According to Changes in Reconstruction Parameters in Lu-177 Dotatate SPECT/CT Imaging
• 발행기관: 대한핵의학기술학회
• 저자명: 박철홍(Cheolhong Park) 김태헌(Taeheon Kim) 고현수(Hyunsoo Ko)
• 간행물 정보: 『핵의학기술』Vol.29 No.1, 22~38쪽, 전체 17쪽
• 주제분류: 의약학 > 방사선과학
• 파일형태: PDF
• 발행일자: 2025.05.31

국문 초록

Purpose: Lu-177 Dotatate SPECT/CT imaging is important for diagnosing and monitoring neuroendocrine tumors. While reconstruction protocols are well-established for scans like Tc-99m and I-131 SPECT/CT, standardized reconstruction conditions for Lu-177 Dotatate remain limited. This study aimed to determine optimal reconstruction tendencies by analyzing phantom and clinical data using different combinations of Iteration (I), Subset (S), and Gaussian Filter (GF). Image quality was assessed using standardized uptake value (SUV), contrast, and qualitative visual evaluation. Materials and Methods: Phantom and clinical images were acquired using a Symbia Intevo 16 system with MELP collimator. ACR PET phantom was prepared at a 200 mCi Dose A level. Clinical data were collected from 10 patients who underwent Lu-177 Dotatate therapy under identical acquisition conditions. SUV and contrast were measured using VOIs; phantom analysis used a 25 mm cylinder, and clinical analysis used identifiable tumors. Twenty-seven reconstruction settings were evaluated (3 I × 3 S × 3 GF combinations), and images were ranked based on SUVmax and contrast. Pearson correlation and Friedman tests with post hoc analysis were used to analyze data. Results: Increasing GF while keeping I and S constant led to decreased SUVmax. Increasing S with fixed I and GF resulted in higher SUVmax, although this effect diminished at GF=16. Similarly, increasing I with constant S and GF led to higher SUVmax, but gains were minimal at higher GF. The results for contrast indicated a decreasing trend as a higher GF was applied. Rankings of phantom and patient images based on SUVmax and contrast showed consistent top-performing conditions across both datasets. The rankings of the phantom data images and the clinical patient data based on SUVmax and contrast conditions showed that the top 40% of ranked conditions were consistent between the two datasets. Pearson correlation revealed a strong correlation in SUVmax (r=0.937) and a strong correlation in contrast (r=0.692) between phantom and patient data. Friedman analysis showed that two conditions (I16/S1/GF16 and I16/S2/GF16) had significantly lower SUVmax values compared to others (p<0.05), while the remaining 25 conditions did not differ significantly (p>0.05). Conclusion: In this study, quantitative and qualitative evaluations of Lu-177 Dotatate SPECT/CT images were performed using various reconstruction conditions based on both phantom and clinical patient data. The analysis of SUVmax and contrast revealed numerical trends depending on the variation of Iteration, Subset, and Gaussian Filter, and a strong correlation was observed between the phantom and clinical data. Statistically significant differences were confirmed for certain conditions based on SUVmax, and appropriate reconstruction settings were selected through qualitative assessment by nuclear medicine physicians. Currently, our institution has adopted two reconstruction conditions, I16/S4/GF0 and I24/S2/GF8, based on the results of this study for clinical image provision, and these settings have demonstrated stable performance in terms of image quality and interpretability.

목차

서론

실험 대상 및 방법

결과

고찰 및 결론

REFERENCES

키워드

Lu-177 Dotatate SPECT/CT Reconstruction Parameter Iteration Subset Gaussian Filter SUV