Hello, Thanks for posting in HCM. Arachnoid cyst usually appears as cystic lesion in MRI. It can be well distinguished from a cancerous lesion. This cyst is normally an incidental finding on MRI. Usually it is asymptomatic. Sometimes it can cause effects like increased intracranial pressure causing headaches and seizures. So keep a lookout if you have any severe headache or have an episode of seizures. Then you need to talk with your doctor about the problem. Usually these cysts are harmless and it will never manifest throughout your life. Only thing is keeping yourself mentally happy. Try to treat your anxiety and panic attack by natural methods with some support. The cyst won’t pose any threat as such. I hope I have answered your query well. If you have any more question kindly write back to me, will be happy to help you out. Thank you