{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T18:13:43Z","timestamp":1779387223780,"version":"3.53.1"},"reference-count":25,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T00:00:00Z","timestamp":1778544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Tomography"],"abstract":"<jats:p>Background: Differentiating adrenal adenomas from non-adenomatous lesions remains a critical challenge in the management of adrenal incidentalomas. Conventional unenhanced CT relies on attenuation thresholds of 10 HU and 20 HU, which present trade-offs between sensitivity and specificity. Objectives: To evaluate the diagnostic performance of unenhanced Spectral CT using the attenuation difference between 40 keV and 140 keV virtual monoenergetic images for differentiating adrenal adenomas from non-adenomatous lesions. Methods: In this retrospective single-center study, 60 patients with adrenal lesions who underwent unenhanced dual-energy CT were included. Mean attenuation values were measured on conventional images and on virtual monoenergetic images at 40 keV and 140 keV. The spectral attenuation difference (\u039440\u2013140 keV) was calculated. ROC analysis was performed to determine the optimal threshold and diagnostic performance. Additional analyses included DeLong comparison of correlated ROC curves and bootstrap resampling to estimate 95% confidence intervals for the area under the curve. Results: Forty-nine lesions were adenomas and eleven were non-adenomatous. The optimal threshold for \u039440\u2013140 keV was \u221217 HU. When evaluated as a continuous variable, \u039440\u2013140 keV yielded an area under the curve of 0.940 (95% confidence interval: 0.851\u20131.000), compared with 0.939 (95% confidence interval: 0.870\u20130.992) for conventional unenhanced attenuation. DeLong comparison showed no statistically significant difference between the two curves (p = 0.980). Diagnostic performance was as follows: HU \u2264 10 (AUC 0.816, diagnostic accuracy 0.70), HU \u2264 20 (AUC 0.883, diagnostic accuracy 0.87), and \u039440\u2013140 keV \u2264 \u221217 HU (AUC 0.940, diagnostic accuracy 0.90). The spectral attenuation difference demonstrated the highest overall diagnostic accuracy. Conclusions: Unenhanced Spectral CT using \u039440\u2013140 keV improves discrimination between adrenal adenomas and non-adenomatous lesions compared with conventional attenuation thresholds. This technique may reduce indeterminate findings and limit the need for additional imaging.<\/jats:p>","DOI":"10.3390\/tomography12050068","type":"journal-article","created":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T16:46:18Z","timestamp":1779381978000},"page":"68","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Differentiation of Adrenal Adenomas from Non-Adenomatous Lesions: Diagnostic Value of Unenhanced Spectral CT"],"prefix":"10.3390","volume":"12","author":[{"given":"Tommasa","family":"Catania","sequence":"first","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grazia","family":"Morabito","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7014-0124","authenticated-orcid":false,"given":"Simone","family":"Barbera","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Massimo","family":"Venturini","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, Circolo Hospital, ASST dei Sette Laghi, University of Insubria, 21100 Varese, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3809-5696","authenticated-orcid":false,"given":"Federico","family":"Fontana","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, Circolo Hospital, ASST dei Sette Laghi, University of Insubria, 21100 Varese, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-9809-7372","authenticated-orcid":false,"given":"Eduardo","family":"Maccarrone","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grazia Maria","family":"Arillotta","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Velio","family":"Ascenti","sequence":"additional","affiliation":[{"name":"Department of Radiology, Policlinico Universitario, University of Milan, 20133 Milano, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvio","family":"Mazziotti","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5218-1075","authenticated-orcid":false,"given":"Thomas Joseph","family":"Vogl","sequence":"additional","affiliation":[{"name":"Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, 60590 Frankfurt am Main, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1426-2402","authenticated-orcid":false,"given":"Giovanni","family":"Foti","sequence":"additional","affiliation":[{"name":"Department of Radiology, IRCCS Sacred Heart Hospital Don Calabria, 37024 Negrar, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0004-6378","authenticated-orcid":false,"given":"Tommaso","family":"D\u2019Angelo","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giorgio","family":"Ascenti","sequence":"additional","affiliation":[{"name":"Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital \u201cPoliclinico G. Martino\u201d, 98124 Messina, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,12]]},"reference":[{"key":"ref_1","first-page":"952","article-title":"Lexicon for adrenal terms at CT and MRI: A consensus of the Society of Abdominal Radiology adrenal neoplasm disease-focused panel","volume":"48","author":"Glazer","year":"2023","journal-title":"Abdom. 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Oncol."}],"container-title":["Tomography"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2379-139X\/12\/5\/68\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T17:38:12Z","timestamp":1779385092000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2379-139X\/12\/5\/68"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,12]]},"references-count":25,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2026,5]]}},"alternative-id":["tomography12050068"],"URL":"https:\/\/doi.org\/10.3390\/tomography12050068","relation":{},"ISSN":["2379-139X"],"issn-type":[{"value":"2379-139X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,12]]}}}