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THIRD
NATIONAL TRIGEMINAL NEURALGIA CONFERENCE CONFERENCE
SUMMARY Comments:
These
are notes I attempted to take from the sessions I attended. Videos were
taken of each session. To the best of my ability, I tried to take these
notes and put them into this summary as accurately as possible. In some
cases, I might have been able to take down everything that was said. In
other cases, I was only able to write down what I felt was the most
important part. I can only hope that I am not reporting any inaccurate
information. While I was not able to attend all of the sessions, the
following is a partial listing of the different sessions we could
attend:
Following
are some of the highlights from the sessions I attended.
*****************************
According
to Dr. Zak (Dr. Joanna Zakrzewska), before starting on a drug therapy it
is very important for the doctor to get an accurate diagnosis. In order
to make a correct diagnosis the doctor needs to listen to the patient
and ask questions. The doctor needs to take a pain history, which should
include asking questions regarding where the pain is located, the type
of pain, how often the pain occurs, and its duration. *****************************
Dr.
Casey said that for people that have constant pain, a pilot study using
IV drip lidocaine has been done. There is a pill form of this called
mexitril that has been used and initial results from this study have
been good. Dr.
Casey also stated that using compounded alternative medications are
showing as good, if not better, results. I did not write down the names
of these compounded alternative meds. ******************************* Dr.
Albert Rhoton showed a 2D video of an excursion through the brain.
Before he started the video he said that a physician's best ally in the
treatment of pain is a well-informed patient. This statement was
repeated by many of the doctors there.
The
video highlighted the various areas of the brain in relation to
Trigeminal Neuralgia. It showed where the nerve exits the brainstem,
what a compressed nerve looks like and the area where MVD's are
performed. Dr.
Rhoton explained that MVD's are performed over the 8th cranial nerve.
Since this nerve is for hearing and balance, this is the reason there is
a higher risk of these side effects when one has an MVD. ****************************** I
attended a session on the Medical, Dental and Surgical Aspects of TN. I
found this to be an exceptionally good session. In this symposium, we
heard that there have been no drug therapy studies specifically for TN
either in the past or at present. 2 new drugs have come out this year,
which are being used for TN, Keppra (sp?) and another. While I am sure
it wasn't trileptal that was mentioned, I did not get the name of this
other drug. Dr.
Steven Graff-Radford, DDS, stated that he doesn't believe dental work
causes TN. Rather, he believes the problem is already there but the
dental work is the proverbial straw that breaks the camel's back.
Therefore, the dental work causes the pain to occur but doesn't create
the problem. On
the other hand, dental work can cause some unfavorable results that
result in neurotrophic pain (pain following trauma to the nerve), which
is not the same as Trigeminal Neuralgia. Dr. Graff-Radford also stated
that there is no documentation that an amalgam filling either causes TN
or makes it worse. Since going to the dentist often results in increased pain, he suggested that we try some of the following possible solutions: take an increased dosage of medication the day before and the day after the dental work (please do this only by notifying your prescribing physician that you are doing so); take a drug such as valium before the appointment; and/or use an anesthetic or nitrous oxide during the visit. Before seeing a dentist, he suggested that a patient ask the dentist if he/she knows anything about Trigeminal Neuralgia and if he has/had any patients with TN. If the answer is no, find another dentist. Dr. Graff-Radford also stated that TN does not cause dental problems. SPECIAL
REQUEST FROM TNA TNA
often gets requests from patients for the name of a dentist that is
knowledgeable about TN in the area in which the patient lives.
Therefore, TNA is compiling a database of the names of dentists. If you
have a dentist you would like to recommend, ask your dentist if you can
have his/her name added to this database. If your dentist agrees, please
contact me or TNA with the your dentist's name, address and telephone
number. ****************************** The
following are my notes from the Glycerol Rhizotomy presentation: Glycerol
is injected with the purpose of damaging the nerve to stop the pain. The
cistern is the area that is targeted to inject the glycerol. The cistern
is the area just before the trigeminal nerve splits into the 3 divisions
when it exits from the ganglion. The
patient lays with their knees bent on a moveable x-ray table that has a
fluoroscope. Having their knees bent allows the patient to be able to
sit up easier after the treatment. The patient is asleep when the needle
is placed into the trigeminal valley. Once the needle is in place, the
patient is woken up and has an IV with contrast to determine how big the
cistern is in order to know how much glycerol should be used. After
this, the patient is moved to a bed and the glycerol is injected. After
the treatment, the patient must sit up for at least 2 hours. The
possible risks of this procedure include infection, sensory loss around
the lips, anesthesia dolorosa, which is usually mild and doesn't occur
often, and meningitis. There have been no reports of keratitis. While
TN can recur after a few years, the procedure can be repeated. This
procedure does not treat the cause of TN. It only blocks the pain. It
was interesting to note that one doctor explained there are 2 different
types of "dolorosa" - anesthesia dolorosa and dysesthesia
dolorosa. ****************************** Dr.
Kim Burchiel stated that TN usually becomes ATN for people who have TN
caused by MS. In addition, some people with MS have been successfully
treated by MVD. Dr.
Burchiel explained that there are differences between TN, ATN and
trigeminal neuropathy. While
ATN is more likely to have some sensory loss, classic TN doesn't.
Trigeminal neuropathy usually occurs after facial trauma, dental work or
sinus surgery. A
few of the characteristics of trigeminal neuropathy are pain in a branch
of the nerve, possibly episodic and constant and/or can feel aching or
burning. ****************************** During each session patients
were given the opportunity to ask questions to the panel members.
Following are some of the questions asked and the answers given: Q:
Why do anti-seizure meds work? A:
At one time TN was thought to be a form of epilepsy and so their use was
just sort of stumbled upon trying to correct the epilepsy Q:
Why do they stop working? A:
It's believed that one doesn't become immune to them. Rather, the pain
becomes greater than the current dosage can control. Q:
What if the pain comes back after a surgical procedure? Dr.
Casey: The data on what to do if it does is sparse at best. Regarding
any surgery, whether it is for the first time or for a repeat, the
patient must weigh the degree of invasiveness vs. the degree of
destruction. It's not only important to have an accurate diagnosis the
first time but the second also. It's important to determine whether the
procedure failed or the pain is something entirely new. Dr.
Apfelbaum: The first step is to go back on the meds. He feels they might
work better after a procedure because the nerve has been treated. He
stated that if it was an MVD that failed, his preference is to do a
repeat with one of the percutaneous procedures, preferably glycerol.
While this has a high recurrence rate, it can be repeated. Dr.
Tew: A repeat MVD is frequently unsuccessful. As with Balloon
Compression and Glycerol Rhizotomy, MVD has an increased risk of serious
side effects, which include AD. His preference for a second procedure if
it was an MVD or Glycerol that failed is to do a Percutaneous
Radiofrequency Rhizotomy. Q:
How many times can a procedure be repeated? A:
MVD, twice. Percutaneous procedures such as RF & Balloon, once.
Glycerol more often but the patient needs a good cistern for a repeat. ****************************** The
panel actually had differing opinions about the amount of times the
various procedures could be repeated especially with the number of times
Glycerol could be repeated. These
3 members of the panel didn't really mention GK as a viable option
either as a first time procedure or as a repeat. Then again, in my
humble opinion, most doctors based their opinions on the procedure that
they prefer to use almost exclusively. Most of the neurosurgeons there
do not perform GK so they rarely, if ever, had anything good to say
about GK and its effectiveness. ****************************** Another
member of the panel was Dr. Young. While Dr. Young has performed all of
the previously mentioned surgical options, he now pretty much does GK
exclusively (as do Dr. Brisman and Dr. Alksne). Dr.
Young: He stated that it is
ok to repeat a GK twice, and possibly three times, but only if a few
years have gone by. Dr.
Brown: If a patient comes back after what appears to be a
"failure," he uses the Magill Pain Questionnaire to correctly
assess the type of pain it is now. He counsels the patient on how and
what component of the pain can be treated. The
panel seemed to be in agreement that if a patient returns with what the
patient perceives to be a failure, it might in actuality not be a
failure at all. They said all characteristics of the original pain must
be the same for the procedure to be a failure. If the pain returns and
it is different in any way, it is something entirely new and not a
failure. If the pain returns in a different division or branch, constant
rather than episodic, aching or burning rather than like a lightning
bolt, to name a few, this is not the same problem that was treated so
the original procedure did not fail. ****************************** The
last day of the conference comprised of 2 sessions. They were:
My
sketchy notes do not do these sessions justice. During
the first session, Dr Zak (Dr. Joanna Zakrzewska), was on a panel of 3 doctors. Dr. Zak explained
she is currently doing research in the UK with hopes to also do research
in the US on what the patients' Quality of Life expectations are when
using drug therapy or with outcomes from a surgical procedure. She asked
us to give her 5 positive, but realistic, outcomes we want from drug
therapy and surgical procedures. She also asked us to give her 5
negative outcomes from drug therapy and surgical procedures we would ACCEPT. Unfortunately,
my notes do not include the active participation from the audience
responding to these questions and the conclusions Dr. Zak reached based
on our answers. The
second session had quite a few components to it but I'm only summarizing
2 of them. In
1999, Claire Patterson went to the National Institute of Health (NIH).
As a result of her meeting there, NIH promised grant money to scientists
for their doing research in different aspects of TN and facial pain
disorders. Cheryl Kitt, PhD from NIH outlined the specific areas in
which NIH has requested research. The NIH web site for this report is at
the end of this summary.
******************************
Patient
Registry: TNA is requesting all patients with TN and other Facial Pain
Disorders complete a Questionnaire prepared by TNA. Future research
might occur based on the answers patients give. Polly Potter reported on
various statistics that have been gathered from the 5,300+/-
questionnaires that have already been submitted. TNA currently has a
database of over 14,000 patients, yet only about 1/3 of patients
responded to the questionnaire. If you have not yet done so, it is
vitally important for all of us that you take a little bit of time and
do so. The survey is online and is located at: Trigeminal Neuralgia Association's International Registry If
you previously completed a survey but something has changed (i.e. meds,
had a surgery, surgery failed, had a repeat, etc.) be sure to file an
updated survey. If you don't remember your unique ID# (like me), they
can access your original one by your date of birth. Mark on your survey
that it is an update. ******************************
There
also was a session in which various doctors presented scientific
abstracts mainly based on statistics from current surgical methods and
drug therapies. Following is information on three of the abstracts. As printed in the program book: DIAGNOSTIC
AND TREATMENT ERRORS IN TYPICAL TRIGEMINAL NEURALGIA Mitesh
Patel (presenter), Anthony M. Kaufmann, MD., K. MacDougall, MD (Calgary,
Canada) Abstract: Methods:
We assessed a consecutive series of 100 patients with typical TN. Data
was collected by interview, pertaining to the details of TN onset,
diagnosis and course. Results:
These patients were referred to our Center
1 month to 40 years (9.3 +/- 9.1 years) following pain onset;
average age of onset was 55 +/- 15 years. Only 31 patients had been
accurately diagnosed by the first medical or dental professional. The
average number of practitioners seen to reach a correct diagnosis was
2.8 +/- (range 2 to 10), 40% of which were dentists/oral surgeons.
Incorrect diagnoses were initially applied to 49 patients. Misguided and
ineffective treatments were performed upon 41, mostly dental extractions
and root canals. Another 3 patients underwent additional dental
extractions for TN pain even after a diagnosis had been established.
There was an increased delay to reach diagnosis for patients initially
assessed by dental versus medical doctors (P=0.06). Furthermore, among
60 patients who saw at least one dentist or oral surgeon, treatment
errors occurred in 63%, compared to 5% who did not see a dental
professional (P<0.001). Conclusions:
Delayed and inaccurate diagnoses remain a common problem facing
individuals suffering from TN. Increased efforts to inform medical, and
especially dental professionals may reduce diagnostic delays and
treatment errors for patients with TN ******************************
Here
is a brief discussion of another abstract presented at the conference by
Dr. Alksne, which will be of vital interest to TNer's. With the advent of the new way of reading an MRI,
medical professionals can better tell if there's a compression and if
there is do an MVD - even for those people with multiple sclerosis. THIN
CUT MRI IMAGING OF TRIGEMINAL NERVE IN TRIGEMINAL NEURALGIA PATIENTS
PRIOR TO THERAPEUTIC DECISION MAKING. Although
most patients with Trigeminal Neuralgia (TGN) have a standard MRI scan
to rule out tumor or multiple sclerosis, the images are usually not
adequate to clearly visualize the trigeminal nerve and determine the
presence or absence of a compressing blood vessel at the root entry
zone. Current thin cut technology using 1 mm cuts without spacing,
however, makes this visualization possible and provides the patient with
the opportunity to know their situation before making a decision about
which therapy to select. ******************************
PREOPERATIVE DETECTION OF TRIGEMINAL
NEUROVASCULAR COMPRESSION BY MRI IMAGING IN PATIENTS
WITH TYPICAL AND ATYPICAL TRIGEMINAL Abstract: In a prospective trial, a sequential series of patients with trigeminal neuralgia (typical and atypical), underwent T2 and 3D-TOF MRI imaging (MRA source images) to determine the rate at which neurovascular compression (NVC) of the trigeminal nerve could be detected by pre-operative imaging. MRI studies were evaluated by a neuroradiologist who was unaware of either the nature or side of the patient's pain. Twenty-five patients had MRI imaging, and 21 of these patients had a retromastoid craniectomy for microsurgical exploration of the region of the trigeminal nerve. Of the four patients who did not have surgery, one had a positive MRI indication of NVC, but remains on medical management; one patient had prior MVD and no demonstrable NVC; one showed no NVC, but later proved to have a neurotropic nasopharyngeal tumor of the mandibular nerve root; and one is awaiting surgery. Twenty of the 21 patients who had a surgery proved to have NVC at time of surgical exploration. The one exception was a patient with occipital neuralgia with an element of facial pain, who had negative MRI imaging and a completely negative exploration of the trigeminal nerve (true negative rate = 1/1 = 100%). Of the patients that showed NVC at surgery, 13 showed arterial NVC, and 12 of these were detected by MRI (12/13 = 92% areterial NVC detection rate). Seven patients proved to have venous NVC at surgery. Six of these patients had preoperative MRI imaging (one patient had severe claustrophobia and the MRI study was aborted). A total of 2/6 were detected by MRI preoperatively (2/6 = 33% venous NVC detection rate). Thus, of the 19 patients with surgically proven NVC who also had preoperative imaging, 14 instances of NVC were detected preoperatively by MRI (true positive rate == 14/19 = 74%). 5/19 patients had surgically-proven NVC and negative MRI imaging (false negative rate = 26%), and in 4/5 cases the NVC was found to be venous in origin. 9/11 (82%) patients with typical TN were found to have NVC by MRI (9/12 patients proved to have had arterial NVC at exploration. 4/6 (66%) P Patients with atypical TN were found to have NVC by MRI (4/6 had venous NVC at surgery). The two patients with MS were both found to have NVC, and the NVC was confirmed at surgery in both cases. This preliminary study demonstrates that trigeminal NVC may be reliably imaged in patients with trigeminal neuralgia. This technique may not only aid in decision making in patients with typical TN, but also in cases of typical TN and symptomatic TN secondary to MS. *****************************
Following
is information and web site url's (if available) for the doctors
mentioned in this summary: Dr.
John F. Alksne
Dr.
Ronald Brisman: Dr.
Jeffrey Brown: Dr.
Kim Burchiel: Dr.
Kenneth Casey: Polly
Croak: Dr.
Steven Graff-Radford, DDS: Dr.
Peter Jannetta: Mitesh
Patel: Cheryl
A. Kitt, PHD: Dr.
Albert Rhoton Jr. Dr.
John Tew Dr.
Ronald Young Dr.
Joanna Zakrzewska |