Pituitary growth/vision

I have a 1cm Pituitary growth.  Thought to be either an adenoma or Rathes Cleft Cyst based on MRI studies.  The MRI shows it to be 1mm away from the optic chiasm. I actually saw the film and it looks to be a perfectly even, although small gap between the growth and the optic chiasm. That seems so close that I feel at any moment my vision could be in jepoardy, but the several doctors I have seen don't seem in a rush to decompress the growth. I understand the situation is complicated by hormones (awaiting those test results) and the pressure issue of a 1 cm growth in the small sella turcia area.  

Please comment on the closeness of the tumor to my vision center.
How risky is it to take a watch and see approach with serial MRIs.  The orig. film was taken early April 07.  Thanks in advance for your comments.

[John C Hagan III, MD, FACS, FAAO]

Your question has been answered by 'circumspect' a physician member of the American Academy of Ophthalmology. Sorry for the delay in getting a response back to you. Hopefully it will be worth the wait.

[circumspect]

I am a board certified ophthalmologist but not the forum physician. Tumors both benign and malignant near the optic nerves do not normally cause sudden loss of vision. Like a glacier they tend to encroach and press on the optic nerves slowly over a period of months, years sometimes even decades. Sudden pressure on the optic nerve or other nerves associated with vision usually come from rapidly dilating blood vessels (aneurysms).

In your case you need the advise and experience of a neurosurgeon that deals frequently with brain tumors. If they advise close observation and feel the risk are lower with observation than with neurosurgery then I would follow their advise.

JCH MD Board Certified Ophthalmologist