MRI and CT Diagnosis of Intracranial Primary Embryonal Carcinomas

Objective To analyze MRI and CT features of intracranial primary embryonal carcinomas so as to make a further understanding of its imaging characteristics,to improve its diagnostic accuracy and to provide clinicians with more useful information. Methods Of the 8 patients,the tumor was located at pineal area in 6 and at sella turcica region in 2. The lesions were manifested as a lobulated( n = 6) or round( n = 2) mass. Contrast-enhanced MRI scanning was performed in 3 patients,both contrast-enhanced MRI scanning and plain CT scanning were carried out in 3 patients and only plain CT scanning was employed in 2 patients. Plain MRI scanning showed that the lesion was iso- or slight low-signal on T1WI with patch high-signal within the tumor,while on T2WI the lesion showed mixed signal with high-signal as the main manifestation. Contrast-enhanced MRI scanning revealed that marked enhancement of the tumor's solid content was seen in 4 cases and moderate enhancement in 2 cases. On plain CT scans the lesions exhibited high density with calcification( n = 2) or cystic degeneration( n = 2). Six lesions had a sharp border and two lesions showed a blurred margin. Peritumoral edema,obvious( n = 2) or mild( n = 2),was seen in 4 cases. Coexisting hydrocephalus,obvious( n = 5) or mild( n = 2),was detected in 7 cases. Implanted metastasis occurred in one case. Conclusion Intracranial primary embryonal carcinomas carry certain MRI and CT features. Through comprehensive analysis the accuracy rate of diagnosis can be markedly improved.