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Rhino-orbito-cerebral mucormycosis is a potentially fatal disease requiring early magnetic resonance imaging (MRI) for disease evaluation and timely detection of intracranial complications. Angio-invasive nature leading to necrosis and infarction is the hallmark of mucormycosis. The disease follows a fulminant course extending from the paranasal sinuses to involve the orbit, deep neck spaces, skull base, facial bones, and intracranial compartment. Loss of vision either due to direct extension into the orbit or optic nerve infarction adds to disease morbidity. Prompt MRI using dedicated sequences can help in assessing the exact disease extent including early osseous and intracranial changes, which aid in precise disease management. [ABSTRACT FROM AUTHOR]

Background: Central nervous system (CNS) tuberculomas often mimic tumors on conventional imaging, differentiation of which may not be possible without invasive tissue sampling. Diffusion tensor imaging (DTI), owing to its unrivalled property of characterizing molecular diffusion, may help in better lesion characterization and tractography may help understand the pattern of white matter involvement by tuberculomas. Purpose: To estimate qualitative and quantitative diffusion tensor changes in brain tuberculomas and to evaluate patterns of white matter involvement using 3D tractography. Material and Methods: Thirty patients with brain tuberculomas were evaluated on a 3-T magnetic resonance scanner. Diffusion tensor images were acquired along 20 non-colinear encoding directions with two b-values (b = 0, b = 1000). Regions of interest (ROIs) were drawn on quantitative fractional anisotropy (FA) and apparent diffusion coefficient (ADC) maps in the center of the tuberculoma and perilesional area. Similar ROIs were placed in contralateral hemispheres for comparison. Tractography maps were also generated. Results: Mean FA in the center and perilesional area of tuberculomas were 0.098 ± 0.041 and 0.311 ± 0.135, respectively. ADC values in corresponding regions were 0.920 ± 0.272 ×10−3 mm2/s and 1.157 ± 0.277 ×10−3 mm2/s. These values were significantly different compared to contralateral similar brain parenchyma. Tractography revealed interruption of white fibers in the center with deviation of fibers at the periphery in the majority of tuberculomas with none showing infiltration of white matter described in tumors. Conclusion: Significant qualitative as well as quantitative DTI changes were seen in tuberculoma and perilesional areas compared to contralateral hemisphere with tractography showing a pattern different from that described in tumors. These findings may help to differentiate tuberculomas from infiltrating tumors. [ABSTRACT FROM AUTHOR]