This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Radiology
A patient with vestibular schwannoma is best investigated by which of the following: 
Select and explain. 
A. SPECT, B. Contrast enhanced CT scan, C. Gadolinum enhanced MRI, D. PET scan
C: Gadolinum enhanced MRI
Answer: C: Gadolinum enhanced MRI 
Explanation: Vestibular schwannoma usually arises in VIII cranial nerve of posterior cranial fossa. CT scan will not give clear picture of posterior cranial fossa tumour < 2cm. MRI scan is the investigation of choice in patient with posterior cranial fossa tumour. Ref: Philippe Demaerel, (2001), Chapter 18, "Imaging of Intracranial Abnormalities in Neurofibramatosis type 1 & 2", In the book, "Recent Advances in Diagnostic Neuroradiology", Springer Publications, USA, Page 283