Deb ,
I am a 48 year old female who suffered hair loss in the back of my head after both open heart surgery and a stroke.Iwent to see a female dermatologist who did not blow off my concern,anxiety and embarrasment.She was very kind and informative.It is a condition known as Telagon Aflubia(spelling) and it is the body's response to severe pyhsical stressors such as the surgery/stroke etc.She started me on a regime of high doses of Predisone to slow down the loss,Started Rogaine topical,and also started Aldactone .The whole issue is the hair is going through a "shedding"phase that is excellerated by the body's response to the trauma.All the above meds slow that process down and allow the "normal cycle of shedding and growth to return.Now 2 years later with this regime I have a normal abundance of hair,it has all grown back.Find some one who will be sensitive to this issue and get treatment.
While alopecia related to stress has been well documented throughout the medical literature, I could not find anything regarding intraoperative positioning, brain tumor (in the absence of chemo and radiation), or neurosurgery and alopecia. Hair loss can certainly be stressful in itself, but many times it is only temporary and has been documented to be reversible when directly related to stress. FOr more info, consider seeing a dermatologist who specializes in alopecia as this is unlikely to be a primary neurologic problem.