O'Connor M K, Oswald W M, Brown M L, Kamath P S, Phillips S F
Department of Radiology and Gastroenterology Research Unit Mayo Clinic, Rochester, MI 55905.
Eur J Nucl Med. 1988;14(11):562-4. doi: 10.1007/BF00286777.
We have developed a method for measurement of organ dimension based on the use of the full width half maximum (FWHM) of profiles taken through an organ. In vitro studies were performed using a large rectangular lucite box filled with water. Five circular lucite phantoms with internal diameters of 1.4-10.2 cm and 1 elliptical phantom with dimensions 9.6 x 4.0 cm were filled with 99mTc-pertechnetate at various concentrations. Phantoms were imaged on a gamma camera at a depth of 5-25 cm in water and the FWHM calculated from horizontal profiles taken across the cylinders. The FWHM showed no variation with 99mTc concentration in the same cylinder. Phantom profiles were deconvolved with a system line spread function measured under similar conditions of scatter and depth. The correction factor to convert the deconvolved profile FWHM to true diameter was independent of cylinder depth and diameter over a range of FWHM 3-10 cm and depth 5-25 cm. The mean value for the correction factor was 1.23 +/- 0.04 for circular phantoms and 1.14 +/- 0.02 for the elliptical phantom. This technique should allow an objective and reproducible estimate of organ dimensions from planar images that is relatively independent of the depth and size of an organ.
我们已经开发出一种基于测量穿过器官的轮廓的半高全宽（FWHM）来测量器官尺寸的方法。使用一个装满水的大型矩形有机玻璃箱进行了体外研究。五个内径为1.4 - 10.2厘米的圆形有机玻璃模型和一个尺寸为9.6×4.0厘米的椭圆形模型被填充了不同浓度的高锝[99mTc]酸盐。模型在水中5 - 25厘米深度处用伽马相机成像，并从横跨圆柱体获取的水平轮廓计算FWHM。在同一圆柱体中，FWHM随99mTc浓度没有变化。模型轮廓用在相似散射和深度条件下测量的系统线扩展函数进行反卷积。在FWHM为3 - 10厘米和深度为5 - 25厘米的范围内，将反卷积后的轮廓FWHM转换为真实直径的校正因子与圆柱体深度和直径无关。圆形模型校正因子的平均值为1.23±0.04，椭圆形模型为1.14±0.02。这项技术应能从平面图像对器官尺寸进行客观且可重复的估计，该估计相对独立于器官的深度和大小。
