I have a cavernous hemangioma in the cerebellum with evidence of previous bleeding. I have chronic headaches, slight dizziness, visual disturbances and some numbness along my left foot, hand and the side of my face. The doctors are unclear whether or not I have had a stroke. My symptoms appeared in my early 40s and I am now a 50 year old female. I have been diagnosed with fairly serious sleep apnea and have been using a CPAP machine (set to 15 as the pressure) for several weeks. While I have adapted to the machine, and sleep well with it, my headaches have been more intense lately. My understanding is that the CPAP machine will reduce pressure in my brain because my heart does not have to pump so much to circulate oxygen. My blood oxygen level dropped significantly at night (down to 60%) during my sleep study. The expectation is that my headaches will improve not get worse. Any idea if the CPAP machine is, in fact, causing my headaches to worsen? It is possible that I am just going through a rough patch. Thanks for you help. I will be seeing my family doctor shortly (as a regular appointment) and we may have to make a choice.