[A case of glioblastoma in which early diagnosis was difficult by MRI]

The authors report a case of glioblastoma in which MR images with Gd-DTPA enhancement changed rapidly during the early stage. A 61 year-old male presented with sudden right facial spasm and dysarthria. However, both a plain and an enhanced CT failed to demonstrate any abnormal lesions. On the other hand, T2 weighted MR image revealed a well circumscribed high intensity lesion in the left frontal lobe without mass effect. This lesion could not be differentiated from cerebral infarction, since no contrast enhanced lesion was able to be observed in T1 weighted MR image with Gd-DTPA. His symptoms gradually became aggravated and at 3 months from the onset, MR image with Gd-DTPA disclosed a small enhanced lesion in the left frontal lobe near the cortical surface. After 6 months from the onset, he suffered from right hemiparesis and motor aphasia. The MR image with Gd-DTPA at this time showed a large enhanced lesion in the left frontal lobe with mass effect. He was admitted to our hospital, and subtotal removal of the tumor and intraoperative radiation was carried out. The patient did well postoperatively without additional neurological deficit, and then he received additional radiation therapy. It should be noted that Gd-DTPA enhanced MR image might fail to reveal the lesion of glioblastoma in its early stage, while T1 weighted image discloses only the gyral swelling.