Role of susceptibility weighted imaging (SWI) in assessment of intra axial brain neoplasms in adults

Abstract

Abstract Background Susceptibility weighted imaging (SWI) is a 3D gradient-echo MR technique that is based on blood oxygen level dependent (BOLD) induced phase effects between the venous blood and the surrounding brain parenchyma. SW-MR imaging allows for noninvasive visualization of small veins at submillimeter resolution and, therefore, is used to depict venous architecture in brain lesions. The extreme sensitivity of SWI for the detection of neovascularity (venous blood), haemorrhage, and calcification has been an indispensable tool for characterization of the internal architecture of brain tumours. Objectives Is to evaluate the role of Susceptibility weighted imaging in assessment of adults Intra axial brain Neoplasms, and its ability to characterize them into high and low grade lesions in comparison to histopathology which will be used as gold standard. Methods A cross sectional study including 31 patients suspecting intracranial brain neoplasm radiologically and clinically, conducted at Private center, the patients were investigated using Siemens machine Magnetom Skyra 3T, the period was between January 2018 till the end of June 2019 . Results Our study included 31 patients. Including 15 female and 16 male patients, with the patient’s age ranging from 20 to 68 years old with median 48 years old ranging from 35.75 (25% percentile) to 58.75 (75% percentile). Among total cases, there were 8 patients with grade 2 glioma, 10 patients with grade 3 glioma and 6 patients with grade 4 glioma, 2 patients with lymphoma and 5 patients with brain metastasis (1 lung cancer and 4 breast cancer). All the patients were evaluated with MRI including SWI sequence with special comment on the number of the intratumoral susceptibility signal (ITSS), the size of the ITSS, its morphology as well as the ratio of the ITSS to the tumor size, which were then correlated with the patient histopathological results obtained later. The study revealed that the best parameter to accurately grade the tumor is the number of ITSS within the lesion with P value 0.001, followed by the size of the ITSS with P value 0.002 and Pearson Chi-Square value equals 20.6, while the lowest one was the ratio of the ITSS to the tumor size with P value 0.002 Pearson Chi-Square value equals 17.3. Our study showed that the morphology alone was not able to accurately grade the tumor with P value 0.007 ( Not significant) Conclusion SWI using 3T MR system provides quite useful information for preoperative tumor grading. There seems to be a strong correlation between pathological grading and that assessed with SWI.