There were 11 responses, of which 8.5 indicated they currently only do open
and closed, and 2.5 indicated they also do a dynamic or incremental
examination (0.5 because only one of the multiple sites associated with
that institution does incremental exams using 3 different mouth pieces).
I haven’t come across a reference specifically mentioning a difference in
treatment based on the point where the disc recaptures. But our ENT docs do
prefer an incremental examination so they can adjust their therapeutic
splint accordingly (as mentioned in my first email). It is certainly
possible that this varies based on institution and surgeon preferences.
Due to provider preference, our current protocol consists of incremental
mouth opening using an opening device. Each audible click of the device
corresponds to 1 mm. We image at closed, 5 clicks, 10 clicks, 15 clicks, 20
clicks, and 25 clicks. The literature does mention that “passive mouth
opening with a Burnet device might not reproduce the physiologic conditions
occurring during mouth opening given the possible role of the lateral
pterygoid muscle in disc stabilization during mouth opening ( http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4147437/ )” so this technique
isn’t perfect either. This obviously makes the exam longer, but need to do
what the provider wants when possible.
A few excerpts from your responses, very much appreciated:
“dynamic is also done though I have found them to often be of limited use
as the quality is often problematic. I’m also not sure how to quantify the
range of motion to disc displacement and recapture as the different phases
on the dynamic sequences seem to vary from study to study and even side to
side.”
“dynamic rapid acquisition during opening and closing, without any
calipers/opening device. Doing the gradual opening with an incremental
device does not give the same result as a continuous opening acquisition
anyway.”
“We just do open and closed. Good thoughts on providing more value to
determine the position where the disc engages, but I’m not sure if it’s
feasible depending on how much time it would add to the study.”
“I do a lot of TMJs and this is our protocol [open and closed only]. One
referring doc is all about reduction, recapture, locks but in all honesty
he wants me to be less descriptive about translation and recapture and
doesn’t even want me to use the word synovitis or describe mandibular
cartilage…”
“I haven’t had surgeons request multiple positions of opening and none said
that partial disc subluxation would be significant. Our techs have trouble
getting patients to keep any open position with the splint – they’d go
crazy doubling their efforts. I think high quality images help a lot
including documenting lateral or medial displacement on coronal scans.”
To prevent this email from becoming super long, I didn’t include exact
details of all the protocols – the main thing I was trying to survey was
how frequently folks are doing incremental or dynamic TMJ MRIs, as opposed
to just open and closed. Looks like open and closed won!
A few did mention talking to their referring clinicians about this – please
let me know what you find out!
Thanks for all your responses!
There were 11 responses, of which 8.5 indicated they currently only do open
and closed, and 2.5 indicated they also do a dynamic or incremental
examination (0.5 because only one of the multiple sites associated with
that institution does incremental exams using 3 different mouth pieces).
I haven’t come across a reference specifically mentioning a difference in
treatment based on the point where the disc recaptures. But our ENT docs do
prefer an incremental examination so they can adjust their therapeutic
splint accordingly (as mentioned in my first email). It is certainly
possible that this varies based on institution and surgeon preferences.
Due to provider preference, our current protocol consists of incremental
mouth opening using an opening device. Each audible click of the device
corresponds to 1 mm. We image at closed, 5 clicks, 10 clicks, 15 clicks, 20
clicks, and 25 clicks. The literature does mention that “passive mouth
opening with a Burnet device might not reproduce the physiologic conditions
occurring during mouth opening given the possible role of the lateral
pterygoid muscle in disc stabilization during mouth opening (
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4147437/ )” so this technique
isn’t perfect either. This obviously makes the exam longer, but need to do
what the provider wants when possible.
A few excerpts from your responses, very much appreciated:
“dynamic is also done though I have found them to often be of limited use
as the quality is often problematic. I’m also not sure how to quantify the
range of motion to disc displacement and recapture as the different phases
on the dynamic sequences seem to vary from study to study and even side to
side.”
“dynamic rapid acquisition during opening and closing, without any
calipers/opening device. Doing the gradual opening with an incremental
device does not give the same result as a continuous opening acquisition
anyway.”
“We just do open and closed. Good thoughts on providing more value to
determine the position where the disc engages, but I’m not sure if it’s
feasible depending on how much time it would add to the study.”
“I do a lot of TMJs and this is our protocol [open and closed only]. One
referring doc is all about reduction, recapture, locks but in all honesty
he wants me to be less descriptive about translation and recapture and
doesn’t even want me to use the word synovitis or describe mandibular
cartilage…”
“I haven’t had surgeons request multiple positions of opening and none said
that partial disc subluxation would be significant. Our techs have trouble
getting patients to keep any open position with the splint – they’d go
crazy doubling their efforts. I think high quality images help a lot
including documenting lateral or medial displacement on coronal scans.”
To prevent this email from becoming super long, I didn’t include exact
details of all the protocols – the main thing I was trying to survey was
how frequently folks are doing incremental or dynamic TMJ MRIs, as opposed
to just open and closed. Looks like open and closed won!
A few did mention talking to their referring clinicians about this – please
let me know what you find out!
Thanks again!
Emad