Tompe Aparna P, Sargar Kiran M, Kazmi Syed A Jaffar, Shimony Nir
Research volunteer, Geisinger Medical Center, Danville, PA, USA.
Department of Radiology, Geisinger Medical Center, Danville, PA, USA.
Radiol Case Rep. 2020 Nov 16;16(1):180-184. doi: 10.1016/j.radcr.2020.11.004. eCollection 2021 Jan.
Subependymal giant cell astrocytomas (SEGAs) are the most common intracranial tumors in Tuberous Sclerosis Complex (TSC). Very few cases of solitary SEGA without a diagnosis of TSC have been described. Most of these previously reported solitary SEGAs were located near the caudothalamic groove or in close proximity to the lateral ventricles. Here, we describe a unique case of solitary extraventricular SEGA in a 17-year-old boy who presented with new-onset seizures in the absence of the clinical and genetic diagnosis of TSC. This extraventricular SEGA was involving white matter and cortex of the occipital lobe and was predominantly hypointense on T1 and T2-weighted images with a markedly hypointense signal on susceptibility-weighted images likely secondary to dense internal calcifications. Solitary SEGA can occur in the extraventricular location in patients without TSC and should be included in the differential diagnosis of a densely calcified supratentorial intra-axial tumor in children, especially during the second decade of life.
室管膜下巨细胞星形细胞瘤（SEGA）是结节性硬化症（TSC）中最常见的颅内肿瘤。很少有未诊断出TSC的孤立性SEGA病例被描述。这些先前报道的孤立性SEGA大多位于丘脑尾状沟附近或靠近侧脑室。在此，我们描述了一例独特的孤立性脑室外SEGA病例，该病例发生在一名17岁男孩身上，他在没有TSC临床和基因诊断的情况下出现了新发癫痫。这个脑室外SEGA累及枕叶的白质和皮质，在T1加权和T2加权图像上主要呈低信号，在磁敏感加权图像上呈明显低信号，可能继发于密集的内部钙化。孤立性SEGA可发生在无TSC患者的脑室外部位，在儿童尤其是青少年期的幕上轴内高密度钙化肿瘤的鉴别诊断中应考虑到。
