Can the width of the nasal bone be reduced with a rasp and not be broken? Asian rhinoplasty. (Photo)

Although you can rasp down the bones on the nasal sidewalls, this is unlikely to give you significant narrowing or your nose.  You share a common characteristic to many Asian patients who have very flat and wide nasal bones.  
I find that Asian patients rarely need osteotomies of their nasal bones if you augment the bridge of your nose with either a synthetic implant or an implant made from your tissue (diced cartilage fascia graft).  
The reason this is true is that once you augment the bridge, you are able to create new dorsal aesthetic lines that are narrower and are defined by the new implant rather than the nasal bones.  The low, wide nasal bones almost disappear as the optical focus shifts to the new nasal bridge.

In general, when we rasp someone's nasal bridge, it appears to take on a wider appearance. Bridge narrowing during rhinoplasty typically involves osteotomies. Thank you. Dr Joseph

To me your bridge doesn’t appear excessively wide. However trying to narrow the bridge with a rasp will get you nowhere. The bones have to be broken and moved inward.

Each patient needs to be individually evaluated from more than the front view. Also your surgeon needs to feel the nasal bones to determine size and shape. Patient care coordinators are not surgeons and can only guess what can be done. Most often Asian nasal bones are so small that shaving or narrowing them via osteotomy does very little to nothing. Adding a little to the bridge can make the nose appear narrower and your eyes appear closer together. 

To reduce the width of the nasal bones requires osteotomies placed in the nasal bones and resetting them itoa more narrow position. It is not possible to rasp the sidewalls

Let me start off with the observation that based on your photos, your dorsum doesn’t look particularly wide. The width of the nasal bones is about 1-2mm, do shaving the sides basically implies shaving almost all of the thickness of the bone and loosing nasal support. In many instances of shallow dorsum that also appears wide, a small dorsal onlay graft may bring the height of the dorsum up and create an illusion of dorsal narrowing. Or just going with the routine option of osteotomies and infracturing the nasal bones is another alternative.

Osteotomies are required to bring the nasal bones in, rasping is not the answer. With that said, Your nasal bones do not look overly wide and if you reduce them then the nasal tip will appear bulbous. The nose is a three dimensional structure and when you refine one area you can take the nose out of balance without addressing the entire nose. Best regards, Michael V. Elam, M.D.