{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:57:52Z","timestamp":1760057872893,"version":"build-2065373602"},"reference-count":50,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,2,25]],"date-time":"2025-02-25T00:00:00Z","timestamp":1740441600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The firmness of meningiomas is a critical factor that impacts the surgical approach recommended for patients. The conventional approaches that couple image processing techniques with radiologists\u2019 visual assessments of magnetic resonance imaging (MRI) proved to be time-consuming and subjective to the physician\u2019s judgment. Recently, machine learning-based methods have emerged to classify MRI instances into firm or soft categories. Typically, such solutions rely on hand-crafted attributes and\/or feature engineering techniques to encode the visual content of patient MRIs. This research introduces a novel adversarial feature learning approach to tackle meningioma firmness classification. Specifically, we present two key contributions: (i) an unsupervised feature extraction approach utilizing the Bidirectional Generative Adversarial Network (BiGAN) and (ii) a depth-wise separable deep learning model were designed to map the relevant MRI features with the predefined meningioma firmness classes. The experiments demonstrated that associating the BiGAN encoder, for unsupervised feature extraction, with a depth-wise separable deep learning model enhances the classification performance. Moreover, the proposed pre-trained BiGAN encoder-based model outperformed relevant state-of-the-art methods in meningioma firmness classification. It achieved an accuracy of 94.7% and a weighted F1-score of 95.0%. This showcases the proposed model\u2019s ability to extract discriminative features and accurately classify meningioma consistency.<\/jats:p>","DOI":"10.3390\/s25051397","type":"journal-article","created":{"date-parts":[[2025,2,25]],"date-time":"2025-02-25T06:13:18Z","timestamp":1740463998000},"page":"1397","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["MRI-Based Meningioma Firmness Classification Using an Adversarial Feature Learning Approach"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1784-9791","authenticated-orcid":false,"given":"Miada","family":"Murad","sequence":"first","affiliation":[{"name":"Computer Science Department, College of Computer and Information Sciences, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5145-6484","authenticated-orcid":false,"given":"Ameur","family":"Touir","sequence":"additional","affiliation":[{"name":"Computer Science Department, College of Computer and Information Sciences, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mohamed Maher","family":"Ben Ismail","sequence":"additional","affiliation":[{"name":"Computer Science Department, College of Computer and Information Sciences, King Saud University, Riyadh 11451, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,25]]},"reference":[{"key":"ref_1","first-page":"679","article-title":"Epidemiology of cancer in Saudi Arabia thru 2010\u20132019: A systematic review with constrained meta-analysis","volume":"7","author":"Alqahtani","year":"2020","journal-title":"AIMS Public Health"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Sahoo, A.K., and Parida, P. 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