Recent Brain MRI discovered whie matter scar tissue

In Nov. 2010, I was involved in an auto accident and I hit the upper, right side of my head against the frame of the sunroof.  It was very painful and I may have lost consciousness briefly as I cannot account for seconds to a couple of minutes.  Forwarding ... I had off-and-on again headaches since the accident, received some chiropratic treatment and was referred to receive a Brain MRI in July 2011.  Although there is no official diagnosis, I am being referred to a specialist and I was told that I have scar tissue in the white matter of my brain cosistent with individuals 20 - 30+ years older than me (I am 49).  

I was wondering how long does it take for scar tissue to develop?  I am also curious to know if this is a process that can be stopped, reversed, or even the progression slowed-down?

Please let me know and thanks in advance.

[Caryopteris]

The Human Brain - Watch Your Head
www.fi.edu/learn/brain/head.html - Cached After one brain injury, you have a three-times greater risk for a second ..... that is often followed by microswelling and the formation of scar tissue. ... A key factor in recovery time is the extent of damage to the white matter, ...


Brain Contusion Imaging
emedicine.medscape.com/article/337782-overview - CachedMay 25, 2011 – Surgical resection of the contused brain tissue is indicated when the patient ... immediately after a high-speed motor vehicle accident demonstrates a large, .... Incidental white matter changes are present in both hemispheres. ... hypointense scar from a prior intraventricular shunt (white arrow). ...