Blood Pressure problem

I am 72 year old female and having a problem with blurring vision with bad next pressure in the back of my neck.  During these episodes my blood pressure soars to 144/128 then 171/125 on 11/24/11.  Then 4 days later I had another episode with bp at 166/118 & 134/118.  Today 11/27/11 seemed as though another one was starting but not full blown, then I took my blood pressure and it is very low, 86/54 & 94/56.  I don't understand what could be wrong jumping from one extreme to another.  

Any advise you could give would be greatly appreciated.

[CCFCardio MD2]

There are a few reasons for blood pressure fluctuation like this, such as autonomic lability, kidney disease, or pheochromocytoma (a catecholamine secreting tumor).  It could also be related to medications you may be taking.  Discuss these symptoms with your physician as they should be evaluated.  Hope this helps.