The Korean Journal of Nuclear Medicine Technology (핵의학기술)
- Volume 16 Issue 2
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- Pages.18-24
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- 2012
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- 1229-9901(pISSN)
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- 2982-8406(eISSN)
The Study on Usefulness of LEAP Collimator in Lung Ventilation SPECT
Lung Ventilation SPECT에서 LEAP Collimator의 유용성에 관한 연구
- Kim, Jung Soo (Department of Nuclear Medicine, Seoul National University Hospital) ;
- Kim, Soo Mee (Department of Nuclear Medicine, Seoul National University College of Medicine) ;
- Kim, Jin Eui (Department of Nuclear Medicine, Seoul National University Hospital) ;
- Lee, Jae Sung (Department of Nuclear Medicine, Seoul National University Hospital) ;
- Lee, Dong Soo (Department of Nuclear Medicine, Seoul National University Hospital)
- 김정수 (서울대학교병원 핵의학과) ;
- 김수미 (서울대학교 의과대학 핵의학교실) ;
- 김진의 (서울대학교병원 핵의학과) ;
- 이재성 (서울대학교병원 핵의학과) ;
- 이동수 (서울대학교병원 핵의학과)
- Received : 2012.06.30
- Accepted : 2012.09.28
- Published : 2012.10.27
Abstract
Purpose : Although lung ventilation SPECT (LV-SPECT) has a good sensitivity in detection of deep lung lesions, it is difficult to apply the LV-SPECT to patients having breathing problems due to limited examination time. In this study, we evaluated the usefulness of LEAP collimator, which provides high detection sensitivity and tolerable resolution, for the LV-SPECT in terms of diagnostic accuracy and examination time. Materials and Methods : Four volunteers inhaled Technegas (370 MBq) and the lung ventilation planar scan (LVPS, 300 counts/view (cpv)) with LEHR collimator was performed using Siemens E.cam scanner as a reference test. LV-SPECT scans were performed with three collimators, LEHR, LEUHR, and LEAP, in low (7 kcpv) and high (70 kcpv) counting modes. The count ratios of left (LT) and right (RT) lung segments were calculated on the geometric mean view of anterior and posterior images for LVPS and on the summed coronal images of LV-SPECT, respectively. Comparing to LVPS, the usefulness of three different collimators for LV-SPECT was evaluated through statistical analysis (paired t-test), on count ratios of lung segments. Results : The average LT:RT ratio in LVPS was 47:53. For LV-SPECT, there were negligible difference of the LT:RT ratios (48:52 on average) among three different collimators in low and high counting modes. Comparing to standard LVPS with LEHR, all LV-SPECTs with different collimators resulted in similar diagnostic accuracy through paired t-test (p>0.05). The scan time in LVPS (6 views) was 17.3 min. For LV-SPECT (128 views) in low counting mode, it took 18.7 (LEUHR), 15.0 (LEHR), and 12.3 min (LEAP), respectively. Conclusion : Comparing to standard LVPS, the LV-SPECT with LEAP in low counting mode provided the comparable diagnostic accuracy in addition to shortened scan time.
Lung SPECT는 planar scan 보다 깊이 위치한 병변을 명확히 보여주며 보다 예민한 것으로 보고되고 있다. 그러나 ventilation SPECT는 정맥주사를 통해 방사성의약품을 주입하는 perfusion SPECT와 다르게 환자의 호흡을 통해 흡입시키므로, 원활한 호흡이 불가능한 환자의 경우 목적 장기에 방사성의약품의 섭취율이 저하되고 검사에 유효한 적정count/rate가 낮아지므로 필연적으로 검사시간이 길어지게 되어 이에 수반되는 여러 문제로 인하여 실제 임상에 적용하기 어려운 실정이다. 따라서 본 연구는 고감도(high sensitivity) 특성을 지닌 AP (All Purpose) 혹은 GP (General Purpose) collimator를 사용하여 low count/rate 환자의 검사시간을 단축시킴으로써 lung ventilation SPECT 임상적용 가능성과 유용성을 평가하였다. 정상 성인 남녀 4명(