These results are interesting. IS the work published yet? Or do you have a prepublication copy of the manuscript? I'd be very interested in reading the specifics of your findings before commenting. All the best,

Shawn

My thinking would be that in order to significantly compromise such strong muscles and bones as the maxofacial area, you are talking about huge energy impact and that is going to play havoc with the white matter tracts running to and from the temporal region (especially mesial temporal areas) and the orbital prefrontal to medial grey matter tracts.  You are at risk for all sorts of DAI leading to partial disconnection in those regions which could translate to memory and executive issues.  Diffusion tensor imaging would likely show you the tract damage better than MRI.  We have had several patients who went over the handlebars of motorcycles and had these facial injuries and were much more behaviorally impaired than "classically" cognitively impaired and could bluff their way through the memory issues much of the time (except in therapy).  So they hated therapy and just wanted to go home and not be bothered.  Send them home  and in a year they are divorced, unemployed and substance abusing (despite having been solid citizens before).  Sort of a modern Phineas Gage group but without the hole through the noggin to make others understand why.  Just my thoughts....

Dear Dr Shawn,

These findings were recently presented at the International Conference of Innovative Dentistry earlier this week as an oral presentation (which won the Best Presentation Award). The full manuscript for the purpose of publication is currently still being drafted

Would be happy to share once the manuscript is ready for publication. I would be happy to share with you a pdf copy of my presentation, if you'd like.

Aside to Dr Orden,

Thank you for the insights into the possible factors influencing the findings that we have. I do agree with you that the huge forces (energy) involved in high velocity impact as seen in motor vehicle accidents could play an important role in altering the white matter integrity.  While its known (at least through experimental studies) that the supraorbital and frontal bones would require greater forces to fracture (about 200 G or more), our findings of patients with both maxillofacial injury and intracranial abnormalities performing better in most neurocognitive assessment as opposed to those mTBI  patients with maxillofacial injury alone, is rather perplexing. This is further supported by the altered WM integrity in these groups, with lower FA values in among pure maxfac # group. Our postulation is that a unique interplay between the forces of the impact and the trajectories of the trauma might offer some valid explanation to this interesting findings.

Also the energy used in the process of breaking such hard bones is not available to go through to harm the underlying tissue (that's what a safety helmet does or a football helmet, for example - helmet is toast so the tissues underneath are not).  It is also why you have to replace a bike helmet every 3 years or after any accident - the lining materials are no longer useful as an energy trap and the energies of a blow go right through.  But the majority of the brain parenchyma is only loosely associated with the pia mater so it is the blood vessels (which run through the arachnoid and have to deal with entrances and exits through bones) and the white matter tracts (which are ultimately attached through the brain stem to the spinal cord and which run through longer spaces within the brain, connecting grey areas) that are vulnerable to the energies of an acceleration/deceleration injury.  The exception of course is the olfactory bulb and tract which run through bone and get sheared off leaving folks unable to smell in frontal injuries and accel/decel ones all the time.  Have you thought about doing a simple olfactory screen with your patients to document that kind of injury?

Dear Shawn K Acheson and Kathryn Oden ,

Here is the article that we published in 2016 after these discussion thread was concluded (Article Microstructural Change and Cognitive Alteration in Maxillofa...