### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
age:25 height:185cm weight:69kg query:i have done ct scan of my brain.in the report it says that there is an abnormal hypodense cystic area in the posterior fossa with relative hypoplasia of left cerebellar hemisphere.what does this mean and how this can be treated?

### output:

Hi, I wouldn't worry about this reading for 2 reasons. 1. CT scans are not terribly sensitive imaging studies to look at the posterior fossa of the brain. In other words, a CT scan is not a great way to evaluate structures in that region of the brain which is essentially the back portion of the head where the spinal cord attaches to the base of the brain and brain stem which is then, attached to the cerebellum. An MRI of the brain is much more sensitive to that area of the brain. 2. Secondly, the cystic area which is hypodense in that region is probably something on the order of an arachnoid cyst which is generally believed to be congenital anatomic variations that are benign and need no further treatment. Because of the fluid-filled cavity contained in such a cyst then, the cerebellum in that area may not actually be suffering from any true abnormalities and the description of hyperplasia (immature development) of the cerebellum may be an artifact as a result of the cystic area obscuring a portion of the cerebellum.  All in all, I'd say that the scan is benign until proven otherwise (which means you have to wait till the radiologist gives you an official reading or your doctor who sent you decides to call you and let you know results) and that in all likelihood the findings need no treatment and no worry.  Hope I have answered your query. Let me know if I can assist you further.  