In most of the cases the following investigations are done to confirm diagnosis of tumor.
1. CT Scan Brain (with contrast): This is a completeinvestigation in itself, but if the tumor is small or is present at the posterior of the brain or the type of the tumor cannot be confirmed on a CT Scan, MRI is required.
2. MRI (Magnetic Resonance Imaging) can be done forconfirmation and is in fact essential in some cases. For accurate diagnosis, sometimes angiography is also needed. If a person has a pace maker or a metal implant in the body MRI cannot be done and in such cases diagnosis has to be based only on CT Scan. Some patients find it difficult to sleep in the MRI chamber for 20 to 30 minutes (claustrophobia). In this condition as well as in small children a sedative or low dose of anesthesia is given and the investigation is carried out.
3. Lumbar puncture: Lumbar puncture is done for theinvestigation of the cerebrospinal fluid. But if the edema in the brain is high this investigation can be dangerous. Therefore in the cases of brain tumor, there is very little scope for this investigation. This investigation is very useful in the diagnosis of the infectious diseases of the brain like meningitis, encephalitis etc.