探讨用现代CT技术将肾上腺结节定性为腺瘤的直方图分析方法是否受到噪声增加的影响,如果允许噪声校正的扩展将提高诊断性能。
这是符合HIPAA标准的,IRB批准的回顾性研究共58例患者。第一组29例患者有33个肾上腺病变,经病理证实为非腺瘤。根据既定的影像学标准,第二组有29例患者,其中33例经病理证实或推测为腺瘤。使用直方图方法评估结节,平均衰减法,以及基于高斯模型的算法,该算法没有(未校正的高斯算法)并且具有针对图像噪声的校正(校正的高斯算法)。灵敏度,特异性,并得出了识别腺瘤的准确性。
当使用直方图分析方法和未校正高斯算法时,在识别腺瘤和非腺瘤方面没有显着差异,两者的特异性都很低,分别为42.4%和47.0%,分别(p=0.30)。将噪声校正添加到高斯算法中,相对于直方图方法,特异性在统计上显着增加(86.4%vs.42.4%,p<0.001)。与平均衰减法相比,校正高斯算法提高了灵敏度(71.2%vs.54.5%,p<0.001),但特异性较低(86.4%vs.100%,p<0.001),和类似的总体准确性(78.8%与77.3%,p=0.74)。
采用现代低剂量CT技术,直方图法区分肾上腺腺瘤和非腺瘤的特异性评分低于之前的高剂量扫描.通过图像噪声校正,可以在数学上提高直方图等效方法的特异性和准确性,并且校正的高斯算法提高了对平均衰减的敏感性,尽管具有较低的特异性,但准确性相似。尽管这表明在肾上腺结节表征中直方图分析的实用性有限,我们的研究证明了其他噪声相关CT表征方法的潜在数学应用。
To investigate whether the histogram analysis method of characterizing adrenal nodules as adenomas is affected by increased noise with modern CT technique, and if an extension that allows for noise correction will improve diagnostic performance.
This is a HIPAA-compliant, IRB-approved retrospective study performed on 58 total patients. The first group of 29 patients had 33 adrenal lesions that were pathology-proven non-adenomas. The second group had 29 patients with 33 pathology-proven or presumed adenomas based on established imaging criteria. The nodules were evaluated using the histogram method, mean attenuation method, and a Gaussian model-based algorithm without (uncorrected Gaussian algorithm) and with correction (corrected Gaussian algorithm) for image noise. Sensitivity, specificity, and accuracy for identifying adenoma were derived.
There were no significant differences in identifying adenoma from non-adenoma when using the histogram analysis method and the uncorrected Gaussian algorithm, both of which had low specificities of 42.4% and 47.0%, respectively (p = 0.30). Adding noise correction to the Gaussian algorithm resulted in a statistically significant increase in specificity relative to the histogram method (86.4% vs. 42.4%, p < 0.001). The corrected Gaussian algorithm improved sensitivity compared to the mean attenuation method (71.2% vs. 54.5%, p < 0.001), but had lower specificity (86.4% vs. 100%, p < 0.001), and similar overall accuracy (78.8% vs. 77.3%, p = 0.74).
With modern low-dose CT technique, the specificity scores of the histogram method for discrimination of adrenal adenomas and non-adenomas are lower than with previous higher dose scans. The specificity and accuracy of a histogram-equivalent method can be increased mathematically through image noise correction, and the corrected Gaussian algorithm has improved sensitivity to the mean attenuation with similar accuracy albeit with lower specificity. Although this suggests limited utility for histogram analysis in adrenal nodule characterization, our study demonstrates the potential mathematical application for other noise-dependent CT characterization methods.