Ritu Manoj Kakkar MBBS, Presenter: Nothing to Disclose

Sameer Surendra Soneji DMRD, Abstract Co-Author: Nothing to Disclose

Vinayak Vishwanath Kabate MBBS, DMRD, Abstract Co-Author: Nothing to Disclose

Shrinivas Balaji Desai MD, Abstract Co-Author: Nothing to Disclose

Determine the benefit of using adjunctive HR-SWI for differentiating SEL of brain by assessing ITSSs compared with conventional imaging alone. Grade the gliomas depending upon the presence of ITSS Compare results with histopathology as the gold standard  

32 Patients (age 15-65) with SEL who met with the inclusion criteria for this study were retrospectively reviewed from our database. Conventional MR and HR-SWI sequences were analysed. ITSS was defined as low-signal-intensity fine linear or dot like structures, which are not obvious on conventional MR images, with or without conglomeration within a tumor as depicted on HR-SWIs. ITSS were graded as Grade 1, no ITSS Grade 2, 1–10 dotlike or fine linear and Grade 3, as ≥ 11 dotlike or fine linear ITSSs. Sensitivity, Specificity, PPV, NPV and diagnostic accuracy were calculated for both conventional imaging alone and with adjunctive HR- SWI imaging, comparing with histopathology as gold standard.

2 radiologists diagnosed accurate tumor pathology within 6 categories (GBM, anaplastic astrocytoma, metastatic tumor, lymphoma, tumefactive MS, and inflammatory granuloma) in 20 (62.5%) of 32 SELs on conventional MR images alone and in 26 (81.3%) of 32 SELs after reviewing both conventional MR images and HR-SWIs. The McNemar test showed statistically significant (P =0.031) difference in overall diagnostic accuracy of conventional MR imaging versus using adjunctive HR-SWI .ITSSs were seen in all 9 GBMs (100%), in 1 of 2 (50%) anaplastic astrocytomas, and in 8 (72.7%) of 11 metastatic tumors and were not identified in lymphomas and nontumorous lesions. Higher grade of ITSS (grade 3) are seen in 8 out 9 GBMs.

The use of ITSSs provides a benefit for the differential diagnosis of SELs compared with conventional imaging. Presence of ITSS reflects increased intratumoral neovascularity and is indicative of higher grade of malignancy .Lack of ITSS can be a specific sign in the imaging diagnosis of lymphomas or nontumorous lesions.

HR-SWI should be included in MR evaluation of SELs, to further validate its role in differential diagnosis.HR- SWI should be combined with proton spectroscopy and perfusion to accurately grade tumors non-invasively and provide accurate site of biopsy.

Kakkar, R, Soneji, S, Kabate, V, Desai, S, To Assess the Added Value and Diagnostic Performance of Intratumoral Susceptibility Signals (ITSS) on High Resolution Susceptibility Weighted MR Imaging (HR-SWI) in the Differential Diagnosis of Solitary Enhancing Brain Lesions (SEL).  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14013485.html