Head and neck lesions: characterization with diffusion-weighted echo-planar MR imaging.

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Head and neck lesions require accurate characterization for effective diagnosis and treatment planning.
• Diffusion-weighted magnetic resonance (MR) imaging offers insights into tissue microstructure.

Purpose of the Study:

• To determine if apparent diffusion coefficients (ADCs) derived from diffusion-weighted echo-planar MR images can effectively characterize head and neck lesions.
• To assess the diagnostic performance of ADCs in distinguishing between different types of head and neck pathologies.

Main Methods:

• Diffusion-weighted echo-planar MR imaging was performed on 97 head and neck lesions in 97 patients using a 1.5-T MR unit.
• Apparent diffusion coefficients (ADCs) were calculated from images acquired with diffusion-weighting factors (b-values) of 0, 500, and 1,000 sec/mm(2).
• ADCs were measured for lesions, cerebrospinal fluid, and spinal cord to establish reference values.

Main Results:

• Diagnostic quality images for ADC measurement were obtained in 84% of patients.
• Significantly lower mean ADCs were observed for malignant lymphomas (0.66 x 10(-3) mm(2)/sec) and carcinomas (1.13 x 10(-3) mm(2)/sec) compared to benign solid tumors (1.56 x 10(-3) mm(2)/sec) and benign cystic lesions (2.05 x 10(-3) mm(2)/sec).
• Using an ADC threshold of 1.22 x 10(-3) mm(2)/sec to predict malignancy yielded an accuracy of 86%, with 84% sensitivity and 91% specificity.

Conclusions:

• Measurement of apparent diffusion coefficients (ADCs) is a valuable tool for characterizing head and neck lesions.
• ADC values can help differentiate between malignant and benign pathologies in the head and neck region.
• Diffusion-weighted MR imaging provides quantitative information that aids in the diagnostic workup of head and neck abnormalities.