Diagnostic Accuracy of Dwi Versus Conventional Mri Sequences in Differentiating Brain Abscess From Necrotic Tumors

Background: Ring-enhancing intracranial lesions pose a frequent diagnostic dilemma on MRI, particularly in distinguishing brain abscesses from necrotic tumors, as these entities often share overlapping imaging features on conventional contrast-enhanced sequences. Accurate differentiation is essential because treatment strategies and prognoses differ markedly. Diffusion-weighted imaging (DWI) has been suggested to improve diagnostic confidence; however, its incremental value over conventional MRI sequences in routine practice remains to be clearly defined. Objective: To compare the diagnostic accuracy of diffusion-weighted imaging with conventional MRI sequences in differentiating brain abscesses from necrotic intracranial tumors. Methods: This retrospective diagnostic accuracy study will include patients with ring-enhancing intracranial lesions identified on brain MRI. Image interpretation will be performed in two stages: first using conventional MRI sequences alone (T1-weighted, T2-weighted, FLAIR, and post-contrast imaging), and subsequently with the addition of DWI and apparent diffusion coefficient (ADC) maps. Imaging diagnoses from both approaches will be compared with a reference standard established by histopathology, surgical findings, microbiological confirmation, or clinicoradiological follow-up. Sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy will be calculated and compared between the two imaging strategies. Conclusion: This study aims to determine whether DWI provides meaningful incremental diagnostic value beyond conventional MRI in evaluating ring-enhancing brain lesions, with potential implications for optimized imaging protocols and improved clinical decision-making.