Arachnoid cysts?

[Allearia]

As part of a study my son was involved in (as a control subject), he had an MRI. The doctor called and sent an image showing an arachnoid cyst in his frontal lobe. She kept assuring me that it was benign, probably been there since before birth, that she was just telling me as a baseline in case he ever has a concussion. She is a neurologist at UCSF so I guess an expert. I did not ask about the size, I will probably call back so I can write that down, it looks big but I have no background. I asked a couple of times about how to tell if it was causing problems but she kept coming back to it being benign.

 

Okay, I figured posting here was better than googling it which was not reassuring. Should I follow up? Should I trust her and ignore it? Should I keep it in mind if I see changes or if there may be things happening that could be a symptom? Should I just forget about Google altogether?

[Aiden]

I would trust that the neurologist probably is right and it's nothing to worry about. However, for my own peace of mind, I'd probably make an appointment with the child's regular doctor to make sure it's in his files and to discuss it. I'd probably want to make an appointment to discuss it with the neurologist as well, if that's possible. I'd google it enough to go in with a list of questions to ask, but I wouldn't freak out about the horror stories--after all, it hasn't caused problems to this point, and you're making the doctor aware of it, so even if it caused problems later (unlikely, based on what the neurologist said), they should be caught early.

[Jean in Newcastle]

I would follow up.  Dd has a tumor in her eye.  We were told that it was probably benign but you can bet they checked it out to make sure.  It was benign.  But we still check it yearly because benign or not, if it grows it could impact her ability to see drastically.  Part of the checking it out involved an MRI but I would want to know in your case if that is all that is normally done or not.  And I would want to talk to a neurologist who is actually treating your son.

[MyHandsAreFull]

I would not worry about an arachnoid cyst. They are very common and usually cause no symptoms. Basically it's a little chunk of the meninges (skin that overlies the brain) with a little CSF (spinal fluid) entrapped in it. That's it. It's not growing tissue or neoplasm.

 

Very rarely they will exert pressure on the adjacent brain and cause some type of problem (depends on what part of the brain is involved a far as what symptoms would be associated). Neurologists like to joke that you only need ONE frontal lobe to be continent (of urine) and socially acceptable. That's not completely true but it seems unlikely an arachnoid cyst in the frontal region would cause many problems.

 

Somewhat unrelated, I know someone who had an arachnoid cyst in her middle cranial fossa and was convinced to have it resected. The surgery was complicated by a fairly large stroke.

 

I guess my point with all of that is: we see arachnoid cysts fairly commonly and off the top of my head I can't think of a case where I honestly believe it made significant problems for anybody AND complications from neurosurgical procedures are not unknown and I would avoid "elective" procedures as much as possible. (Sadly every now and then you see something get done and the only apparent reason is somebody figured they could bill an insurance company for it.)

 

HTH.