Brief Answer:
Large arachnoid cyst in specific location might cause symptoms

Detailed Answer:
Hi XXXXX,
Thanks for writing in to us.

I have read through your query in detail.
Please find my observations below.

1. In the last few years I have dealt with about 138 patients having arachnoid cysts in their head and none of them had a serious concern. Some of the patients did have occasional headaches and discomfort but all of them were managed by medications. Rarely symptoms are directly linked to the presence of arachnoid cyst.

Since your son has got an arachnoid cyst, it will help to know the exact location (in right frontal lobe) and details about size of the cyst. All arachnoid cysts are benign but should a cyst grow in a specific location then only it can be held responsible for the symptoms that your son is having.

An arachnoid cyst is not a tumor. It is fluid filled and the symptoms might be due to pressure inside the cyst. It does not carry any risk of tumor or cancer transformation. Please be assured about that.

Doing a non invasive investigation like an electroencephalography might also throw some light on the vision and and cognitive problems. This will map the electrical activity in the brain and tell us if it has anything to do with increased activity at or near to the arachnoid cyst.

2. It is good that you have appointments with Neurologist and Cardiologist soon. It is important to do a complete clinical examination as your son is having significant weight loss and chest pain. The weight loss might me has to be evaluated with blood tests (other than blood sugar) and investigations concerning heart function or any chronic medical condition including infection.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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