Parraga Grace, Mathew Lindsay, Etemad-Rezai Roya, McCormack David G, Santyr Giles E
The Lawson Health Research Institute, London, ON, Canada.
Acad Radiol. 2008 Jun;15(6):776-85. doi: 10.1016/j.acra.2008.03.003.
Hyperpolarized (3)He magnetic resonance imaging ventilation defects have been observed in subjects with respiratory disorders. We quantified (3)He ventilation defects in elderly and middle-aged subjects who had no history of smoking, respiratory, or cardiovascular disorders.
Hyperpolarized (3)He magnetic resonance imaging ventilation defect volume (VDV) and ventilation defect score (VDS) were assessed in eight elderly healthy volunteers (mean 67+/-6 years) scanned twice within 7+/-2 minutes and again 7+/-2 days later. A younger cohort of 24 subjects (mean 44+/-10 years) was also scanned for direct comparison. Four observers blinded to scan timepoint and subject identity scored VDS and manually segmented VDV in all center coronal slices.
Center coronal slice ventilation defects were observed in six of eight elderly subjects (ages 63-74 years, 5 males) in all scans acquired and in no middle-aged subjects. At the scan timepoint, mean VDS was 2.7 (mean VDV 52+/-34 cm(3)), whereas for same-day rescan, mean VDS was 2.5 (mean VDV 53+/-35 cm(3)) and at 7-day rescan, mean VDS was 3.6 (mean VDV 48+/-39 cm(3)). Interscan coefficients of variation (COV) for mean VDV was 1.8% (same-day rescan) and 5.3% (7-day rescan) and interobserver COV ranged from 10-12%.
Elderly subjects have ventilation defects that are reproducible in same-day scanning and 7-day scanning visits. The observation of reproducible pulmonary ventilation defects in otherwise healthy elderly volunteers suggests caution must be used in interpreting results from (3)He studies of elderly subjects.
在患有呼吸系统疾病的受试者中观察到超极化（3）氦磁共振成像通气缺陷。我们对没有吸烟、呼吸或心血管疾病史的老年和中年受试者的（3）氦通气缺陷进行了量化。
对8名老年健康志愿者（平均年龄67±6岁）在7±2分钟内进行两次扫描，并在7±2天后再次扫描，评估超极化（3）氦磁共振成像通气缺陷体积（VDV）和通气缺陷评分（VDS）。还扫描了一组年龄较小的24名受试者（平均年龄44±10岁）进行直接比较。4名对扫描时间点和受试者身份不知情的观察者对所有中心冠状切片的VDS进行评分，并手动分割VDV。
在所有采集的扫描中，8名老年受试者（年龄63 - 74岁，5名男性）中有6名在中心冠状切片上观察到通气缺陷，而中年受试者未观察到。在扫描时间点，平均VDS为2.7（平均VDV 52±34 cm³），同日再次扫描时，平均VDS为2.5（平均VDV 53±35 cm³），7天再次扫描时，平均VDS为3.6（平均VDV 48±39 cm³）。平均VDV的扫描间变异系数（COV）为1.8%（同日再次扫描）和5.3%（7天再次扫描），观察者间COV范围为10 - 12%。
老年受试者的通气缺陷在同日扫描和7天扫描随访中具有可重复性。在其他方面健康的老年志愿者中观察到可重复的肺通气缺陷表明，在解释老年受试者的（3）氦研究结果时必须谨慎。
