Noma S, Moskowitz G W, Herman P G, Khan A, Rojas K A
Department of Radiology, Long Island Jewish Medical Center, Albert Einstein College of Medicine, New Hyde Park, New York 11042.
Invest Radiol. 1992 Jun;27(6):429-35. doi: 10.1097/00004424-199206000-00006.
The objective of this study is to evaluate the mild physiologic changes of elastase-induced pulmonary emphysema in the pig by radionuclide scintigraphy and to correlate these findings with high-resolution computed tomography (HRCT) and histologic examination.
Eight 7- to 12-week-old Yorkshire pigs were studied. Perfusion and ventilation studies were performed in six pigs at 1- or 2-week intervals after elastase instillation. HRCT was simultaneously performed for correlation with radionuclide scintigraphy. For the perfusion scans, technetium 99m (99mTc) macroaggregated albumin (MAA) was used, and both planar and single-photon emission CT (SPECT) images were obtained. Ventilation studies were performed with xenon-133 gas with dynamic sequential imaging.
Histopathologic findings demonstrated dilatation and destruction of the alveoli and were similar to those previously reported by the authors. The SPECT perfusion images showed significantly impaired perfusion of the involved segment of the lung, corresponding to the region where elastase was instilled. The planar xenon-133 ventilation scintigraphy did not show abnormal air trapping. The mild emphysema induced with elastase manifested as decreased and impaired perfusion with no detectable ventilation abnormalities. The sensitivity of SPECT perfusion studies for the detection of the mild changes of elastase-induced pulmonary emphysema were higher than that of HRCT.
The perfusion studies reflect functional or physiologic changes in contrast to structural changes seen on HRCT. This pig model was valuable to study the scintigraphic manifestation of elastase-induced pulmonary emphysema.
本研究的目的是通过放射性核素闪烁扫描评估猪弹性蛋白酶诱导的肺气肿的轻度生理变化，并将这些发现与高分辨率计算机断层扫描（HRCT）和组织学检查相关联。
对8只7至12周龄的约克夏猪进行研究。在弹性蛋白酶注入后1或2周的间隔时间，对6只猪进行灌注和通气研究。同时进行HRCT以与放射性核素闪烁扫描相关联。对于灌注扫描，使用锝99m（99mTc）标记的大颗粒白蛋白（MAA），并获得平面和单光子发射计算机断层扫描（SPECT）图像。通气研究使用氙-133气体进行动态序列成像。
组织病理学发现显示肺泡扩张和破坏，与作者先前报道的相似。SPECT灌注图像显示肺受累节段的灌注明显受损，对应于弹性蛋白酶注入的区域。平面氙-133通气闪烁扫描未显示异常气体潴留。弹性蛋白酶诱导的轻度肺气肿表现为灌注减少和受损，未检测到通气异常。SPECT灌注研究检测弹性蛋白酶诱导的肺气肿轻度变化的敏感性高于HRCT。
与HRCT上看到的结构变化相比，灌注研究反映了功能或生理变化。该猪模型对于研究弹性蛋白酶诱导的肺气肿的闪烁扫描表现具有重要价值。
