# Integrated Multiparametric MRI Scoring System-Based Approach in Differentiating Adrenal Adenoma From Other Adrenal Lesions

## TL;DR

This study introduces a new MRI scoring system to accurately distinguish adrenal adenomas from other adrenal lesions using multiple imaging parameters.

## Contribution

A novel multiparametric MRI scoring system is proposed for improved differentiation of adrenal adenomas.

## Key findings

- The scoring system achieved 98.6% sensitivity and 93.8% specificity in diagnosing adrenal adenomas.
- Homogeneous T2-weighted signal intensity was identified as a highly specific feature of adrenal adenomas.

## Abstract

Introduction

Advancements in imaging technology have led to increased detection of adrenal lesions.Differentiating adrenal adenomas from other lesions is crucial for therapy guidance and avoiding unnecessary interventions. The study aims to develop and assess the diagnostic efficacy of a holistic multiparametric magnetic resonance imaging (mpMRI) scoring system in distinguishing adrenal adenomas from other lesions.

Methods

After obtaining ethical approval, a retrospective observational study was conducted at a single center. It included 77 patients who underwent adrenal MRI with confirmed diagnoses via pathology or typical computed tomography (CT)/MRI findings. A fellowship-trained body imaging radiologist reviewed the MRI examinations, assessing key characteristics including size, T2-weighted imaging (T2WI) signal intensity (SI), chemical shift imaging (CSI), and contrast washout at five minutes. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Accordingly, the scoring system was created, and a total score of 3 or more was considered diagnostic for adrenal adenoma.

Results

Using a score of 3 or higher as a diagnostic threshold for adrenal adenoma, the multiparametric MRI (mpMRI) scoring system demonstrated high diagnostic accuracy, yielding a sensitivity of 98.6%, specificity of 93.8%, PPV of 98.6%, and NPV of 93.8%. Interestingly, homogeneous T2-weighted signal intensity emerged as a highly specific and distinguishing characteristic of adrenal adenomas, reinforcing its diagnostic value in differentiating them from other adrenal lesions.

Conclusion

Implementing the mpMRI scoring system to differentiate adrenal adenomas from other adrenal lesions has significantly increased the diagnostic yield of adrenal MRI compared to the old approach that solely depended on the presence of microscopic fat. However, a key limitation of this study is the reliance on imaging findings rather than histopathological confirmation for most cases. This reflects real-world clinical practice but highlights the need for further prospective validation.