
CASE
A 52 year-old male is admitted with sudden onset of weakness affecting the left arm. He has a background of grade III astrocytoma of the right parietal lobe which was resected. This was followed by radiotherapy which was completed around 12 months ago. Over the last 2 weeks, he has been getting daily throbbing headaches lasting around 2 hours and associated with nausea and photophobia. On examination, he has power 0/5 in all muscle groups of the left arm. Two days after hospital admission, he has 4 episodes of twitching over the left side of the face which progress to generalised tonic-clonic seizures. He is started on a loading dose of phenytoin with good effect. MRI FLAIR, T1 post-contrast and DWI do not show any acute abnormality compared to previous scans. However, the weakness persists and on day 7 of admission a repeat MRI is performed. FLAIR, T1 post-contrast and DWI sequences are shown below. What is the most likely diagnosis?

A. Hypoxic brain injury
B. MELAS
C. Tumour progression
D. Seizures secondary to acute stroke
E. SMART syndrome