JAN 20, 2023
Ocular Pathology/Oncology, Oculoplastics/Orbit
A systematic literature review was conducted to examine the clinical use of apparent diffusion coefficient (ADC) value as a diagnostic tool in differentiating benign from malignant orbital lesions.
Original articles that reported ADC values for orbital lesions were included in the analysis.
Malignant orbital tumors were found to have a lower mean ADC value than benign masses; as well, lymphoma has a lower ADC value than other malignant masses. A proposed ADC threshold for distinguishing lymphoma from other orbital neoplastic and non-neoplastic lesions is <0.775 × 10−3 mm2/s, and a proposed ADC threshold for distinguishing orbital lesions from lymphoma is >0.92 × 10−3 mm2/s.
Apparent diffusion coefficient values are subject to variability, which limits the ability to use them as a universal cutoff for diagnostic value. Additionally, ADC values can overlap for multiple pathologies, and so cannot be the only measurement for diagnosis.
Differentiating between lymphoma and idiopathic orbital inflammation currently lacks a straightforward, low-risk (nonsurgical) method of diagnosis. While the use of ADC should be limited to a supplementary tool, it can still play a role in guiding diagnosis in certain situations.
Financial Disclosures: Dr. Barmettler discloses no financial relationships.