Diffusion tensor magnetic resonance imaging of optic pathway in cases of suprasellar masses

Abstract

BackgroundDiffusion tensor imaging (DTI) is a novel MRI technique which can provide information of the compressed tissue’s microstructural properties. The evaluation of visual function is important for the clinical management of patients with suprasellar mass lesion. Compression of the optic nerve and chiasm due to pituitary mass lesions often leads to impaired visual function. The evaluation and prognosis of visual function are important for patient management. The aim of this work is to evaluate the feasibility of DTI in the evaluation of the optic pathway in patients with suprasellar masses. Fifty patients were included in the study, 24 cases with suprasellar masses and 26 cases without suprasellar masses as a control group. All patients underwent detailed history taking, MRI of the sella with coronal and sagittal T1, and coronal T2 sequences and DTI. The region of interests (ROIs) were set on the optic chiasm as well as the anterior and posterior optic tracts. For each ROI, axial diffusivity (AD), radial diffusivity (RD), fractional anisotropy (FA), and apparent diffusion coefficient (ADC) values were calculated. DTI parameters of cases group were compared with normal control group parameters.ResultsThe result of this study showed that in cases with suprasellar masses, there were significantly lower mean AD and ADC values and higher mean FA value than control group with no masses.ConclusionThe DTI is a useful technique in the assessment of optic pathway compression degree by suprasellar masses. This will provide the clinicians and surgeons with precise information about the degree of the visual field compromise in correlation with the clinical data.