Transcript Bipolar

Good Vibrations:
Management of Deep Brain
Stimulation for ET and PD
Michael Pourfar, MD
Co-Director Center for Neuromodulation
NYU Langone Medical Center
New York, NY
Deep Brain Stimulation
Precise placement of stimulating
electrodes into various brain
structures - (thalamus, subthalamic
nucleus, globus pallidus)
Indications
FDA approved:
– Essential Tremor (Vim thal)
– Parkinson’s Disease (STN, GPi, Vim)
FDA HDE:
– Dystonia (GPi, STN)
– OCD (AlIC)
Possible future indications:
–
–
–
–
–
Tourette’s (CM thal, GPi)
Depression (ACC )
Cluster headache (posterior hypothalamus)
Epilepsy (medial temp, ant thal)
Chorea (HD, neuroacanthocytosis, etc)
How DBS works (?)
In movement disorders, there are specific
altered firing patterns, increased neuronal
synchronization and low-frequency
rhythmic oscillation of neurons within the
basal ganglia and thalamus.
DBS may override the altered patterns and
low-frequency oscillations by replacing it
with tonic high-frequency output.
How DBS really works…
Regardless of how DBS theoretically
works, it only ACTUALLY works when a
well positioned lead in a well selected
patient is well programmed!
A great DBS surgeon who doesn’t
program effectively or a proficient
programmer working with misplaced leads
will result in an unhappy patient!
Goals of DBS
Programming
Suppress/improve symptoms
Minimize adverse effects
Reduce battery drain
Programming Basics
Know your target and what it treats
Select contact with the best efficacy and
largest therapeutic window
Decide whether monopolar or bipolar
preferable based on efficacy/tolerability
Select voltage that suppresses symptoms
maximally without inducing SEs
Select pulse width & frequency similarly,
changing one variable at a time
Stimulation Parameters
Pulse Width
(sec)
duration of each stimulus
Amplitude
(Volts)
intensity of stimulation
Rate
(Hertz)
number of pulses
per second
DBS Lead Electrode Selection
* The negative electrode exerts the therapeutic effect
Contact Selection
Generally start with monopolar and shift to
bipolar if limited by side effects at low thresholds
since bipolar reduces volume of stim (assuming
parity of other settings) and is thus generally
better tolerated but a little weaker.
If significant limitations even in bipolar, consider
assessing lead location with imaging
Familiarize yourself with where neurosurgeon
generally implants the base
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3
2
1
-
0
+
3
2
-
1
0
3
2
1
+
-
+
0
3
2
1
0
-
+
+
-
3
-
2
1
0
+
Amplitude
Effective voltage usually between 1-3.5V
If you you’re above 3.6v, consider increasing
PW or adding an adjacent contact to reduce
voltage if possible
In rare cases you may need to go into 4-5v
range even after increasing PW
Avoid the urge to “turn up the juice” each visit.
Higher settings do not equal greater efficacy.
Pulse Width
60ms works for the majority of cases
For severe tremor patients, 90ms (and
occasionally 120ms) may be necessary to avoid
using a high voltage. Rarely require > 120
PD patients with significant dyskinesias and/or
dystonia may also benefit from higher PW but
would start with 60 and re-evaluate patient
ON/ON before increasing
Frequency
Frequency of 130Hz or higher is generally felt to
be most effective for the cardinal motor features.
The benefits of going > 130Hz are often minor
but increases represent an opportunity for
further tweaking when approaching high V/PW
Some evidence that lower F (e.g. 60Hz) may
benefit gait in PD and DYT1 dystonia. Can be
considered when lack of efficacy or side effects
using higher F
Typical Stimulation Parameters
Parameter
STN
GPi
VIM
Amplitude
1.0 – 3.6 V
2.0 – 3.6 V
1.5 – 3.6 V
Pulse Width
60-90 µsec
90-120 µsec
90-120 µsec
Rate
135 – 185 Hz
135 – 185 Hz
135 – 185 Hz
Electrode
Configuration
Unipolar: single
electrode or 2
adjacent electrodes
Bipolar: 2 adjacent
electrodes
Unipolar: single
electrode or 2
adjacent electrodes
Bipolar: 2 adjacent
electrodes
Unipolar: single
electrode or 2
adjacent electrodes
Bipolar: 2 adjacent
electrodes
Pre-Surgical Considerations
Patient Selection
Lead Location
Pre-Operative Assessments
Defining the team roles
Closing the loop with referral source
Patient Selection
Regardless of the indication, the
importance of optimal patient selection
cannot be overemphasized!
– Screen for appropriate diagnosis
– Screen for appropriate medication trials
– Screen for responsiveness of sx to DBS
– Screen for red flags and contraindications
– Screen for realistic expectations
– Screen for understanding and support
How can DBS Therapy help me
Achieve Daily Victories?
DBS for ET
Della Flora, Mov Dis 2010
Patient Selection: ET
Establish/confirm diagnosis
Review medication trials
Assess/document severity and impairment
Review expectations
Essential Tremor: Diagnosis
Confirm the diagnosis
– Pure action tremor or mixed action/rest
– What body parts involved/troublesome
– Any other parkinsonian features
– Any evident ataxic component
– Assess tandem gait, balance, speech
– Establish what positions bring out maximal
tremor and what tasks most impacted
– Imaging for evidence of secondary cause
Essential Tremor: Medications
Beta-blockers and primidone are mainstays.
Both should have been tried at reasonable
doses with documentation of max tolerated
dose or reasons contraindicated.
– Primidone can be > 750mg in divided doses
– No specific beta-blocker but max tolerated within
usual effective range for given choice
– Combo of both if high doses not tolerated
Trials of gabapentin, topirimate, benzo and
sodium oxybate can be considered
Botulinum for head tremors
Essential Tremor: Severity
When is a tremor severe enough?
– Does the patient consider it mild, moderate or
severe and why?
– What ADLs are impacted and to what extent?
Eat with spoon, cutting, with assist
Drink with straw, two hands, half filled
Writing at all legible, typing impacted
Other specific ADLs that are impacted and whether
they are important to work, social function
– What is the social impact?
Avoidance of activities, embarrassment in social or
work events
Essential Tremor: Rating
Video tape position that brings out tremor
maximally and specific impaired tasks
Fahn-Tolosa, TETRAS or other rating scale
Spiral and simple sentence (upper tremor)
Cup to mouth or cup transfer documenting
rough % spill with standard cup size
Sustained “eeee” or other for voice
Video Front/profile for head
Tremor Scale
Tremor Scale
Description
0
Absent (no tremor or writing
impairment)
1
Slight and infrequently present (mild
tremor, writing, and drawing of spiral
minimally impaired)
2
Moderate; bothersome to most
patients (writing and drawing of spiral
moderately impaired)
3
Severe tremor (writing and drawing
severely impaired; interferes with
many activities such as drinking
liquids)
4
Marked tremor (interferes with most
activities)
Available at http://www.wemove.org/et/et_ts.html. Accessed June 3, 2012.
ET Tremor
ET-Intraoperative considerations
MER utilized or not? Sensory followed by
Motor or straight to motor nucleus (VIM)?
– If MER performed, was face, hand, footspecific responsiveness identified?
Any tremor-response in OR and if so was
it clear if lower or higher contacts best?
Any stim-related side effects elicited and if
so, what were thresholds?
Any post-operative issues or imaging?
VIM Lead Placement for tremor
VIM Mapping
MER-guided multiple trajectory approach
•Posterior-Anterior Progression:
•Multiple trajectories
•VC (posterior) - VIM
(anterior)
•Somatotopy preserved
Axial View
ET Initial Programming
Ideally off medications but often not a major
factor given ltd efficacy in most
Standard tasks that do not overly fatigue
(e.g., spirals, finger-nose, sustention)
Start with standard PW (60 or 90) and F
(130-185) and march slowly up voltages by
0.5v increments starting with C+0- up to C+3even if effective with C+0Try to be consistent, especially in labeling:
Specify L VIM, L IPG or R body in notes
ET Initial Programming Cont
Document benefit and side effect thresholds
for each contact
If side effects, wait to see if abate before
abandoning the contact (especially if vague
or sensory in nature unless severe)
If effective, observe for breakthrough and
less evident side effects like speech/balance
ET PROGRAMMING MOVIE
See Video
Initial Programming Notes, Case 1
L IPG
PW 60
F145
– C+0-: Reduced tremor 2.5, persistent paresthesias 3.5
– C+1-: Reduced at 1.5, best at 2.5 well tol to 3.5**
– C+2-: Less effective but well tolerated to 3.5
– C+3-: Vague SE at 3.5, no clear impact on tremor
Initial Programming Notes, Case 1
L IPG
PW 60
F145
– C+0-: Reduced tremor 2.5, persistent paresthesias 3.5
– C+1-: Reduced at 1.5, best at 2.5 well tol to 3.5**
– C+2-: Less effective but well tolerated to 3.5
– C+3-: Vague SE at 3.5, no clear impact on tremor
Final Impression: C+0- and 1- best with
preference for 1- given tolerability
Initial Programming Notes, case 2
L IPG
– C+0– C+1– C+2– C+3-
PW 60
F 145
well tolerated but no benefit at 4v
similar to 0speech trouble at 3v, no benefit
speech trouble at 2.5-3v, no benefit
Initial Programming Notes, case 2
L IPG
–
–
–
–
C+0C+1C+2C+3-
PW 60
F 145
well tolerated but no benefit at 4v
similar to 0speech trouble at 3v, no benefit
speech trouble at 2.5-3v, no benefit
Tried C+0- and 1- with PW90: some benefit
(1->0-) but speech at 3.5
0+1- improved tremor at 3.5/90/185, well
tolerated
Initial Programming Notes, case 2
L IPG
–
–
–
–
C+0C+1C+2C+3-
PW 60
F 145
well tolerated but no benefit at 4v
similar to 0speech trouble at 3v, no benefit
speech trouble at 2.5-3v, no benefit
Tried C+0- and 1- with PW90: some benefit (1->0-)
but speech at 3.5
0+1- improved tremor at 3.5/90/185, well tolerated
Final Impression: Lower leads better but limiting
side effects in monopolar, decent with 0+1-
Programming for ET:
Troubleshooting
ET programming is usually straightforward
but you can hit limitations due to speech or
balance even with a well-positioned lead
and especially with bilateral stim
– DBS is approved for unilateral stim but often
used for bilateral
Identify whether the problem is stimulation
or disease-related (e.g., observe stim off)
Assess whether higher, lower or no stim
makes problem better or worse if not clear
Advanced Programming for ET 1:
Poor Tremor Control
When monopolar is not effective despite
going up to 90ms, try 120ms. If still not
effective by 150ms despite F up to 185,
higher PW are rarely the answer:
– Consider two adjacent contacts or even 3 or 4
– If then limited by side effects but some
efficacy, can try using 2 or 3 electrodes in
bipolar mode (e.g., 3+0-1-) or interleaving
Advanced Programming for ET 2:
Poor Tolerability
If not well tolerated in monopolar and
ineffective in simple bipolar consider:
– Multiple electrodes in bipolar (3+0- or 2+0-1-)
– Interleaving sometimes allows use of
monopolar if split with bipolar
L VIM1 C+0- 2.5/60/125
L VIM2 2+1- 3.5/90/125
If not well tolerated in simple bipolar:
– Consider sandwiching most effective contact
0+1-2+ may allow for higher settings
DBS for non-ET Tremor
DBS has been performed for a number of
non-ET tremor disorders
– MS tremor
– Holmes/post-stroke tremor
– Dystonic and myoclonic tremor
– Metabolic/genetic tremor syndromes
– Orthostatic tremor
Non-ET Tremor
The programming approach is similar to
that of ET but the results tend to be less
uniform and significantly impacted by nontremor pathology that may continue to
impair ADLs.
– In MS, for example, ataxia often overwhelms
the benefit accrued from reduction of tremor
– Proximal tremors may be harder to control
than distally predominant tremors
Differentiating between tremor
reduction and functional improvement
Matthieu, 2007
DBS for MS: Short term results
5 MS patients, mean duration MS 6 yrs,
received VIM DBS.
3 mos follow-up demonstrated 40% reduced
tremor using modified Fahn
scale/spirography
18% improvement in ADLs
No adverse outcomes
Small, lacking long term results but
demonstrates safety and potential for benefit
when tremor is predominant issue.
Mandat, Neurol Neurochir Pol, 2010
Long term results: MS Tremor
12 yr follow-up 9 patients (6 lesion, 3 DBS)
Tremor recurred in all except 2 within 3
months but those 2 (both in the DBS cohort)
remained tremor free for 5y
At yr 12, 5 patients had died (median 5.8y
post surgery) and the 4 survivors were
extremely disabled (EDSS 8-8.5).
Suggests potential for sustained benefit with
DBS but ultimately, disease course may
overwhelm benefit.
Hassan, Eur J Neurol, 2012
Specific Concerns: DBS and MS
Potential increased risk of perioperative
seizures (2 reported in Johnson, Br J NS 2010)
Potential for progressive disease/burden of
hemiparesis or ataxia (assess rate of change)
No clearly reported cases of DBS-induced
MS exacerbations but focal demyelination
may be induced at site of stim (observe postmortem in one case, Moore, MS, 2009)
DBS for MS Tremor
DBS for abeta-lipoproteinemia
DBS for Parkinson’s
60 y.o. gentleman
with 20 years of
Parkinson’s, motor
fluctuations and
tremors that did not
respond well to
levodopa.
“Ideal” PD DBS Candidate
§Age: 40-70
§Symptomatic for 5-10 years or more
§Initial Good Response to L-DOPA
§Marked ‘on/off’ phenomena
§Dyskinesias
§No ON Freezing/Gait Disturbance
§Cognitively Intact
PATIENT SELECTION: PD
Best LD response helps determine benefit
Generally 5 year history to exclude atypicals
No significant neuropsychiatric co-morbidity
No absolute age cut-off but younger is better
Ability to tolerate surgery
Access to follow-up
What are patient expectations?
What improves with DBS?
Depends on site of stim but the following generally
improve to varying degrees:
Tremor (resting and action)
Rigidity
Bradykinesia
Dyskinesias
Active > fixed dystonia
Motor fluctuations
What doesn’t always improve?
Gait may or may not depending on the nature
Freezing seldom improves though OFF may
Symptoms present when ON meds
Balance/Falls
Autonomic symptoms (sweating, orthostasis)
Fixed dystonia/posture
Mood (though OFF anxiety may)
What may worsen?
Speech
(often partly reversible)
Balance/ataxia (reversible)
Mood (reversible but prescreen for SI)
Weight
(common)
Dystonia (uncommon)
The in-between candidate
Try to outline for patients which of their
symptoms are likely to persist
Be wary when complaints include gait and
balance unless ON very different from OFF
– OFF freezing typically segues to ON
– Positive pull test will likely lead to gait limitations
Be wary of very anxious or depressed
patients even if you think it’s PD-related
Be wary of hallucinations even if iatrogenic
N=96 STN, 36=GPi
NEMJ 2001;345:956-963
The Pre-DBS Talk
Review patient expectations clearly
– What do you consider your biggest troubles
– The following should/may/likely won’t improve
– Would you be happy if x improved and y didn’t
– Document this along with avg ON time per day
The Pre-DBS talk
Review anticipated timeline
– Explain it’s not a “light switch” and can take
months to achieve optimal settings
– Explain possible microlesion effect and that it
may wane over days to weeks
– Explain that reducing meds is often possible
but is not the goal of surgery…improving and
extending ON time is the goal
Out-patient follow-up:
Initial programming visit
Review of all contacts for tolerability & efficacy
– If available, preview intraoperative macrostimulation results
or discuss impression with neurosurgeon
Takes about 45m for one side, 90m for bilateral +
time to observe following medications
Select contacts with optimal effect at lowest settings.
Adjustment of medications if/when possible
Tools of the Trade
DBS Settings
Date: _____________
Left
Right
Serial N. _____________
Serial N. _____________
V: 0 PW: 210 F : 30
V: 0 PW: 210 F : 30
Contacts: 3+, 0-
Contacts: 3+, 0-
Usage ____/____=____ Reset 
Usage ____/____=____ Reset 
Impedance Check
O-, C+ Imp. ____  Batt. V ____ Current ____ O-, C+ Imp. ____  Batt. V ____
Current ____
1-, C+ Imp. ____  Batt. V ____ Current ____ 1-, C+ Imp. ____  Batt. V ____
Current ____
2-, C+ Imp. ____  Batt. V ____ Current ____ 2-, C+ Imp. ____  Batt. V ____
Current ____ 3-, C+ Imp. ____  Batt. V ____ Current ____ 3-, C+ Imp. ____ 
Batt. V ____ Current ____
Initial Programming
Left
PW: ___ F: ____
Contact
Amp
0-, C+
0.5
Right PW: ___ F: ____
Comments
Contact
Amp
0-, C+
0.5
1.0
1.0
1.5
1.5
2.0
2.0
2.5
2.5
3.0
3.0
3.5
3.5
4.0
4.0
CONTACT 0 IMPRESSION:
Comments
Lead Location Directly
Influences Programming: STN
dorsal
lateral
medial
Thalamus
ventral
GPi
Paresthesias &
other sensory
phenomena
diplopia,other
oculomotor
disturbances,
mydriasis
STN
affective changes
Substantia
nigra
muscular contractions,
dysarthria
Reduction of rigidity, tremor,
akinesia/bradykinesia,
inductin of dyskinesia
Basic topography
Sensory complaints: posterior or medial
Motor complaints: anterior or lateral
Remember that,
assuming typical angle
of approach, contacts
become increasingly
lateral as you go up.
Proper STN Lead Placement
STN LEAD PLACEMENT
Average Settings
For Parkinson’s
– Voltages from 1 to 3.6
– Pulse width from 60-90ms (occas 120)
– Frequency from 130-185 Hz
With Soletra, will double current drain above
3.6v so try to maintain below if possible. This
is not the case with Kinetra, new PC or
rechargeable but higher V still drains faster
PROGRAMMING BASICS: I
Know the disease and DBS target for
which you’re stimulating!
– Vim works mainly for tremors
– STN and GPi work for tremors, rigidity,
bradykinesia, +/- gait and +/- dystonia
Make sure you and patient are talking
same language
– Right symptom versus Right IPG
– Tremor versus dyskinesias
PROGRAMMING BASICS: II
Have a good sense of the baseline symptom
severity off medications before programming.
– Use rating scales and/or notes
Pick one or two of most evident DBS-responsive
symptoms to track
– Rigidity & tremor usually most reliable. Bradykinesia
& gait can be prone to patient fatigue and variability
PROGRAMMING BASICS:III
As you go through each contact, try to be
systematic and change only one variable
at a time to avoid confusion.
Spend time creating a “programming
map.” It will save time in the long-run.
Identify side effect thresholds and try to
create an image in your mind about lead
placement or at least tolerable limits.
PD PROGRAMMING VIDEO
See Video 2
Programming around capsular side effects
Initial Programming Summary
C+0C+1C+2C+3-
2.5/60/145
3.5/60/145
3.5/60/145
3.5/60/145
chin pulling
mild pull, no change
subtle pull, no change
no change, well tol.
----------------------------------------------------------------------
C+2C+31+20+1-2-
2.5/90/145
3.5/90/145
3.5/90/145
3.0/90/145
chin pulling, no change
no change, well tol
mild improvement, well tol
tremor improved, well tol
Before sending your patient home
Observe patient ON stim and have them take
their highest scheduled dose of medications.
Observe for 45-60m. Patient can return if dose
failure or can’t wait.
Generally reduce initial setting (e.g., >1v below
any side effects) to gauge effect over time
Go over Patient Programmer and med plan
Consider how many options to allow patient
Double check which program they’re leaving on
When to return after initial
programming?
Generally 2-4 weeks for 2nd follow-up
unless using multiple groups
After that, depending on symptom and
programming complexity, every 1-3
months until optimized. Avg 4 visits in 6m
Once stable, routine follow-up generally
every 4 months or every 6-12 months if
receiving additional care elsewhere
SAMPLE CASE
67 year-old gentleman with approximately 17
years of Parkinson’s. He has moderate motor
fluctuations and dyskinesias. Off time with
marked left > right tremors, moderate left > right
bradykinesia and rigidity, slow gait.
Meds: carbidopa/levodopa 25/100 CR tid,
10/100 tid, comtan tid, mirapex 1 bid,
amantadine bid
INITIAL PROGRAMMING
Left IPG (PW60/F145)
C+0good tremor/rigidity reduction by 2.5
C+1good tremor/rigidity reduction by 1.5-2
C+2slightly less improvement but good at 2
C+3no SE, improved tremor> rig
Right IPG (PW60/F145)
C+0little baseline sx w/o much change, good tol
C+1same
C+2perhaps improvement of mild rig at 2
C+3little change, well tol to 3.5
INITIAL PROGRAMMING
Left IPG (PW60/F145)
C+0good tremor/rigidity reduction by 2.5
C+1good tremor/rigidity reduction by 1.5-2
C+2slightly less improvement but good at 2
C+3no SE, improved tremor> rig
Right IPG (PW60/F145)
C+0little baseline sx w/o much change, good tol
C+1same
C+2perhaps improvement of mild rig at 2
C+3little change, well tol to 3.5
INITIAL SETTINGS
INITIAL SETTINGS:
L: C+1- 1.5/60/145
R: C+2- 1.5/60/145
Observe ON meds/ON stim for 45min.
Looked good with mild dyskinesias.
Medication plan:
carbidopa/levodopa 25/100 CR tid, 10/100 tid,
comtan tid, mirapex 1 bid, amantadine bid
Drop comtan. If still dyskinetic or feeling
better after 1 week, can try dropping mirapex
to daily then off.
FIRST FOLLOW-UP: One month
done well, occasional off day, some OFF chin
tremor and mild ON dyskinesias but otherwise
has been very happy and has reduced his meds.
– 25/100CR + 10/100 bid-tid and +/- Mpx 1 PRN
Exam off meds looks very good w/ only chin
tremor and mild LLE rigidity.
Bumped up R IPG voltage from 1.5 to 2v which
helped chin tremor but when observed ON/ON,
he was clearly more dyskinetic so set slightly
lower (1.8) and instructed to hold mirapex and
cut 10/100’s to ½ if possible or if dyskinetic.
L: C+1- 1.5/60/145
R: C+2- 1.8/60/145
Second Follow-up: 1 mo. later
Feels improved though lowering meds more led
to increased OFF time and still somewhat
bothered by ON dyskinesias. ON/ON exam very
good but mild right arm rigidity, mild dyskinesias.
Meds: 25/100 CR + 10/100 AM and PM w/ ½ of
both at noon, rare Mirapex 1 qD,
Increased L IPG voltage to 2.1, which improved
rigidity but worsened dyskinesias so tried adding
a higher contact, with lower V and did well.
Try new setting and see if balance any better by
re-increasing midday 10/100 at noon if balance
and gait continue to feel worse than before.
L: C+1-3- 1.2/60/145
R: C+2- 2.1/60/145
OK, that sounds nice…but…
What to do when no contact seems
evidently helpful?
– Pick a contact based on side effect profile
– Does seem best tolerated dorsal? ventral?
– If still unsure, start with low traditional settings
(e.g., C+1- or 2- 1.5/60/145), assess in 2 wks
– Consider ON med exam if dyskinesitic patient
– Don’t despair (yet)!
Follow-up Visits: General
Check DBS parameters and batteries
– # of activations
– impedance
– battery usage
Development of stimulation or medication
related side-effects
Development of psychiatric and/or
cognitive changes
Use of Patient Parameters
With new single and dual channel IPGs can
allow patient to increase either V/PW/F (only
one component)
Make sure you set limits and patient is
capable of understanding.
Helpful in allowing them to slowly ramp up
from a sub-therapeutic start point
Helpful for fine tuning when maximal control
of symptoms leads to some side effects (e.g.,
tremor/speech)
Patient Parameter example
Ideal symptom control at 3v but you note
dyskinesias ON/ON
Can send patient out at 1v and have them
build up to 2v over next week, reducing
medications if possible and monitoring
dyskinesias or other side effects.
After 1-2 weeks can call with report and
then go up to 3v if needed.
Use of Groups
Changing groups is a little harder for the
patient than changing voltages so make sure
patient or caregiver understand/can
Can use A, B, C and D but I advise against >
2 unless compelling reasons
Employ different groups when you’re not
sure which electrode is preferable or different
sx respond to different electrodes.
Helpful when you don’t have a great handle
on optimal settings or limited follow-up
Use of Group Example 1
Group A: C+1- 2.4/60/145
– Seems to help rigidity and tremor but not gait
Group B: 2+0-1- 3.0/90/185
– Higher V with 1- not well tolerated but ok in
bipolar and bring in 0- to see if helps gait
Group C: C+1-2- 1.8/60/130
– If A and B not helpful, can try addition of 2-
Use of Group Example 2
Group A: C+2- 3.0/60/145
– Patient came in with this, happy but some
residual OFF rigidity and ON dyskinesias
Group B: 0-1+2- 3.6/60/145
– See if introduction of 0- helps added off time
and change to bipolar causes less ON LID
Group C: Interleave C+2- 3.2/60/125 and
1+3- 2.0/90/125
– See if higher V helps residual OFF but
addition of 3- offsets possible worsening LID
The challenging case…
Limiting side effects from stimulation
– Misplaced or sub-optimally placed lead?
– Can be compensated for with programming?
– Consider MRI or discussion with surgeon
Limiting side effects
What can’t be programmed around?
– Pulling at low settings is very limiting. Can try
bipolar but if still pulling, change contact
– Strong paresthesias that don’t abate > 5m
– Evident speech impairment
What can you wait out?
– Mild-moderate paresthesias
– Funny but vague light-headed, whoozy
Is the side effect truly stimulator-related?
– Assess OFF stim condition if unsure
More Creative Programming
When getting limiting side effects with
monopolar and not getting adequate control with
bipolar (despite high V and PW), consider
sandwiching two electrodes or using wider
bipolar field:
– 0+1-2-3+
– 0-3+ or 0+3-
When higher electrodes improve one symptom
and lower ones another, can try:
– 0-1+3-
The Challenging case
OFF symptoms better but remains dyskinetic
– Assess possibility of further med reductions
– Eval ON/ON and program specifically for dyskinesia.
– Turn off stim and assess underlying dyskinesias. Is
stim exacerbating or simply not helping dyskinesias?
If stim exacerbating or causing dyskinesias,
consider different contact, bipolar or lower setting
If stim simply not helping, consider raising settings
or alternate contact
Persistent dyskinesias
Is DBS improving or exacerbating dyskinesias?
Turn DBS OFF in the ON
med state and see impact
If unclear, push
parameters and see if
improves or worsens
If worsening it, consider
lower settings, bipolar or
different contact (in
addition or in place)
Stim-driven dyskinesias
Interleaving
See interleaving graphic
Interleaving
Interleaving involves the rapid alternating
between two different settings for the
same lead.
You cannot use the same active contacts
for program1 and program2
You must use the same frequency (which
will be reduced as a result) but can vary
the voltage and pulse width
When to use Interleaving
You will likely not frequently need it
Consider when one contact seems best
but has some side effect limitations when
used exclusively
Consider it when two very different
symptoms that respond to different
electrodes (e.g., tremor/dyskinesias) but
when both electrodes are not well
tolerated when used simultaneously
Interleaving sample
Setting A: ventral stim
Setting C: dorsal stim
Stim-related? Stim-responsive?
Ask yourself is the complaint likely to improve with programming?
• When in doubt review best med ON exam and consider pushing
dose to establish potential for further improvement.
• If you suspect something may be caused by DBS, you can always
check the symptom with DBS OFF
The challenging case…
Lack of improvement despite good tolerability
–
–
–
–
Are the symptoms normally DBS-responsive?
Optimal lead position and adequate stimulation?
Unrealistic expectations?
Consider significant programming change, e.g. if
stimulating C+1-, try C+3– If still no luck, consider consult with major DBS center
The challenging case…
Sudden loss of efficacy
– Check IPG’s both ON, not end of battery life?
– Hardware malfunction?
– Change in underlying condition?
The Impedance Test
Usual
range
Current
Impedance
Short
circuit
25-150
> 250
microamps microamps
500-1500
< 50 ohms
Open
circuit
<7
microamps
> 2000
ohms
If unsure, can contact Medtronic technical support: 800-707-0933
Images of lead fracture
Garg et al, 2010
Some Final Thoughts
Programming remains more art than science but
having a scientific approach makes the art easier.
It’s hard to do harm programming if you keep
within therapeutic parameters so don’t be timid in
experimenting with different settings.
Be patient and encourage your patients to be the
same even if initial programmings are difficult.
Don’t change or increase settings just for the sake
of it or to try and achieve perfection. Don’t try new
settings for things that don’t typically respond to
changes. At the same time, don’t avoid trying new
settings if a patient’s status changes.
The Rewards of Programming
Getting comfortable with programming is
no walk in the park…but once you’ve got
a handle on it, you’ll help others walk
through the park with greater ease!
Suggested Readings
Volkmann et al. Basic algorithms for the
programming of deep brain stimulation in
Parkinson's disease. Mov Disord 2006; 21 Suppl
14:S284-9
Okun et al. A case-based review of
troubleshooting deep brain stimulator issues in
movement and neuropsychiatric disorders.
Parkinsonism Relat Disord 2008; 14 (7): 532-8
Special Thanks
NYU: Dr. Mogilner, Maria Gillego
Medtronic: Joe Pagano, Annette Carlson,
Andrea Larson, John Bailey, Kirk Finnis
NANS Team: Peter Hurwitz, Elise Reaves,
Chris Weber
Co-Presenters: Drs. Charles, Gudesblatt,
Agrawal, Labar, Saper, Rosenow, Oh
Thank You!
Feel free to follow-up with emails:
[email protected]
Please remember to leave feedback on how
we can improve for future sessions.
Happy Programming!