الفهرس 
Orbital anatomyOnly 14 pages are availabe for public view
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Abstract
Orbital space-occupying lesions represent a broad spectrum of benign and malignant diseases, many of which are difficult to differentiate on the basis of clinical or radiologic criteria. Diffusion-weighted (DW) imaging is a promising magnetic resonance (MR) imaging technique that may help distinguish malignant lesions from benign mimics.
DW imaging is predominantly used to identify acute infarct, which has characteristic high signal intensity on DW images, with associated low signal intensity on apparent diffusion coefficient (ADC) maps. Increasing emphasis on quantitative measurement of ADC has led to an increasing role in the characterization of solid masses, with at least one prospectively validated algorithm that incorporates DW imaging in the characterization of indeterminate brain masses. Despite technical limitations related to the commonly used echo-planar imaging pulse sequences, DW imaging has also been increasingly used to help characterize lesions of the head and neck. Parallel imaging has helped decrease echo-planar imaging–related artifacts in the head and neck, likely by decreasing effective echo time. Some of the larger studies have proposed specific threshold ADC values that may differentiate benign from malignant lesions.
The aim of this study is to evaluate the role of diffusion weighted MRI in the adult non osseous orbital lesions.