case_images: PMC5154202_01
case_images: Initial multimodal imaging after admission. (a) Cranial computed tomography without contrast. The image shows an approximately 3.5 cm measuring lesion thalamic lesion with compression of the right lateral ventricle and consecutive midline-shift of 4 mm. The lesion appears heterogeneous with peripheral enhancement and central hypodensity. No intense perifocal edema was present. (b) Cranial magnetic resonance imaging. Axial T1 sequences without contrast show a poorly demarcated, circumscribed mass in the right thalamic area having a space-consuming effect with compression of the right lateral ventricle. (c) T1 sequence with contrast reveals a heterogeneous pattern of avid enhancement (b, axial T1 with gadolinium) and focal hypertense margins surrounding a hypotense area (c, Axial MPRage). (d) An axial T2 sequence displays dispositions of irregular blood products as well as enlarged vessels draining the lesion at its rostral and caudal margins
case_images: SNI-7-883-g001.jpg
case_images: PMC5154202_01_SNI-7-883-g001.jpg
case_images: F1
case_images: A cranial computed tomography (CT) showed an approximately 3.5 cm nodular right-sided thalamic lesion with heterogeneous enhancement, a central hypodensity, and mild midline shift [Figure 1a]. The lesion showed avid heterogeneous contrast enhancement with highly prominent vasculature consisting of multiple feeders and enlarged venous channels [Figure 1b-d].
case_images: Multimodal angiography. (a) Cranial computed tomography angiography with axial sections displaying a highly vascularized lesion with posteriorly located hemorrhage and focal calcification. (b, c) Correlating coronal and sagittal images demonstrate the specific aspect of this lesion with dilated marginal vessels almost entirely surrounding and draining it. (d, e) Cerebral digital subtraction angiography confirms arteriovenous malformation-like morphology with sagittal and coronal images visualizing a vascular lesion with enlarged draining veins and multiple vessels feeding into a nidus at the posterior margin of the lesion (arrows)
case_images: SNI-7-883-g002.jpg
case_images: PMC5154202_01_SNI-7-883-g002.jpg
case_images: F2
case_images: Here, the mass was characterized by numerous dense calcifications, as well as by intrinsic hemorrhage posteriorly [Figure 2a]. Other significant findings included marked dilatation of clustered vessels along the medial, posterior, and superior margins of this lesion [Figure 2b and c]. AVM, resulting in high flow enlarged draining veins and hemorrhage versus an aggressive glioma with neovascularization [Figure 2c]. A cerebral digital subtraction angiography (DSA) confirmed extensive hypervascularity and was interpreted as displaying AVM-typical morphology [Figure 2d and e].
case_images: Multivoxel magnetic resonance spectroscopy reveals aberrant metabolic function. An increased creatinine/choline peak ratio of 2.41 ppm was found within the lesion, matching the metabolic signature of glioblastoma multiforme
case_images: SNI-7-883-g003.jpg
case_images: PMC5154202_01_SNI-7-883-g003.jpg
case_images: F3
case_images: Three-dimensional planning of a frame-based stereotactic biopsy. (a, b) The target point was set to the lateral posterior margin of the lesion with respect to the major vascular aggregations for limiting the bleeding risk. The procedure was planned in a CRW frame using the Stereocalc software (Radionics, Burlington, MA)
case_images: SNI-7-883-g004.jpg
case_images: PMC5154202_01_SNI-7-883-g004.jpg
case_images: F4
case_images: MR as well as CTA-images were fused to the intraoperative frame-based CT using the StereoCalc  and NeuroSight  Arc software (Radionics Inc., Burlington MA) allowing three-dimensional planning of coordinates. Meticulous attention was paid to the delineation of a suitable target area for the biopsy at the inferior margin of the hypervascular zone but avoiding any prominent vessels [Figure 4a and b].