1. Evaluation of relative wash-in ratio of adrenal lesions at early biphasic CT.
- Author
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Foti G, Faccioli N, Manfredi R, Mantovani W, and Mucelli RP
- Subjects
- Adrenal Gland Neoplasms pathology, Adrenal Gland Neoplasms surgery, Adrenocortical Adenoma pathology, Adrenocortical Adenoma surgery, Adult, Aged, Aged, 80 and over, Algorithms, Biopsy, Chi-Square Distribution, Diagnosis, Differential, Female, Humans, Male, Middle Aged, Neoplasm Metastasis, Predictive Value of Tests, Radiographic Image Interpretation, Computer-Assisted, Retrospective Studies, Sensitivity and Specificity, Statistics, Nonparametric, Adrenal Gland Neoplasms diagnostic imaging, Adrenocortical Adenoma diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
Objective: The purpose of this study was to retrospectively evaluate the accuracy of unenhanced attenuation and relative percentage wash-in ratio in early, that is, arterial and portal venous phase, biphasic CT in differentiating adrenal adenomas from metastatic lesions., Materials and Methods: One hundred seven adrenal masses in 86 consecutively registered patients (45 men, 41 women; mean age, 56 years) were evaluated. Diagnosis was achieved with percutaneous biopsy (n = 6), surgery (n = 13), and at least 1 year of imaging follow-up (n = 88). Unenhanced, arterial phase, and portal phase scans were obtained. Diameter and absolute attenuation values in each phase of CT were measured in a region of interest covering one to two thirds of a lesion. Relative percentage wash-in ratio was calculated. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in differentiation of adenomas from metastatic lesions were calculated for unenhanced attenuation and for wash-in ratio. A value of p < 0.05 was considered significant., Results: The final diagnosis was metastasis in 51 cases and adenoma in 56 cases. A significant difference was found between benign and malignant lesions in regard to diameter (p = 0.001), unenhanced CT attenuation (p = 0.001), and relative percentage wash-in ratio from the arterial to the portal venous scan (p = 0.014). In the differentiation of benign from malignant lesions, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of unenhanced CT attenuation (at an 11-HU threshold) were 98%, 86%, 86%, 98%, and 92%, and those of relative percentage wash-in ratio from the arterial to the portal venous phase were 94%, 77%, 79%, 93%, and 85%., Conclusion: Relative percentage wash-in ratio may help in differentiating adenoma from metastasis and in guiding the decision to perform CT directed at the adrenal glands when unenhanced CT is not available.
- Published
- 2010
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