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Good Vibrations : Management of Deep Brain Stimulation for ET and PD Michael Pourfar, MD Co-Director Center for Neuromodulation NYU Langone Medical Center.

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Presentation on theme: "Good Vibrations : Management of Deep Brain Stimulation for ET and PD Michael Pourfar, MD Co-Director Center for Neuromodulation NYU Langone Medical Center."— Presentation transcript:

1 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

2 Deep Brain Stimulation Precise placement of stimulating electrodes into various brain structures - (thalamus, subthalamic nucleus, globus pallidus)

3 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)

4 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.

5 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!

6 Goals of DBS Programming Suppress/improve symptoms Minimize adverse effects Reduce battery drain

7 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

8 Stimulation Parameters Rate (Hertz) number of pulses per second Pulse Width (  sec) duration of each stimulus Amplitude (Volts) intensity of stimulation

9 DBS Lead Electrode Selection * The negative electrode exerts the therapeutic effect

10 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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16 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.

17 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

18 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

19 Typical Stimulation Parameters ParameterSTNGPiVIM Amplitude1.0 – 3.6 V2.0 – 3.6 V1.5 – 3.6 V Pulse Width60-90 µsec90-120 µsec Rate135 – 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

20 Pre-Surgical Considerations Patient Selection Lead Location Pre-Operative Assessments Defining the team roles Closing the loop with referral source

21 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

22 Non-Surgical Imperatives of DBS Confirm the diagnosis (e.g., rule out atypical disorders, medications response) Assess if medications have been optimized Visualize the patient’s best and worst Assess whether main complaints would benefit Explore patient’s understanding and neuropsych Follow-up programming and med adjustments Communicate with neurosurgeon and follow-up programming/medication team

23 How can DBS Therapy help me Achieve Daily Victories?

24 DBS for ET Della Flora, Mov Dis 2010

25 Patient Selection: ET Establish/confirm diagnosis Review medication trials Assess/document severity and impairment Review expectations

26 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

27 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

28 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

29 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

30 Tremor Scale Description 0Absent (no tremor or writing impairment) 1Slight and infrequently present (mild tremor, writing, and drawing of spiral minimally impaired) 2Moderate; bothersome to most patients (writing and drawing of spiral moderately impaired) 3Severe tremor (writing and drawing severely impaired; interferes with many activities such as drinking liquids) 4Marked tremor (interferes with most activities) Available at http://www.wemove.org/et/et_ts.html. Accessed June 3, 2012.http://www.wemove.org/et/et_ts.html

31 ET Tremor

32 ET-Intraoperative considerations MER utilized or not? Sensory followed by Motor or straight to motor nucleus (VIM)? –If MER performed, was face, hand, foot- specific 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?

33 VIM Lead Placement for tremor

34 VIM Mapping

35 MER-guided multiple trajectory approach Axial View Posterior-Anterior Progression: Multiple trajectories VC (posterior) - VIM (anterior) Somatotopy preserved

36 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+3- even if effective with C+0- Try to be consistent, especially in labeling: Specify L VIM, L IPG or R body in notes

37 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

38 ET PROGRAMMING MOVIE See Video

39 Initial Programming Notes, Case 1 L IPGPW 60F145 –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

40 Initial Programming Notes, Case 1 L IPGPW 60F145 –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

41 Initial Programming Notes, case 2 L IPGPW 60F 145 –C+0-well tolerated but no benefit at 4v –C+1-similar to 0- –C+2-speech trouble at 3v, no benefit –C+3-speech trouble at 2.5-3v, no benefit

42 Initial Programming Notes, case 2 L IPGPW 60F 145 –C+0-well tolerated but no benefit at 4v –C+1-similar to 0- –C+2-speech trouble at 3v, no benefit –C+3-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

43 Initial Programming Notes, case 2 L IPGPW 60F 145 –C+0-well tolerated but no benefit at 4v –C+1-similar to 0- –C+2-speech trouble at 3v, no benefit –C+3-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-

44 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

45 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

46 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

47 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

48 Non-ET Tremor The programming approach is similar to that of ET but the results tend to be less uniform and significantly impacted by non- tremor 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

49 Differentiating between tremor reduction and functional improvement Matthieu, 2007

50 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

51 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

52 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 post- mortem in one case, Moore, MS, 2009)

53 DBS for MS Tremor

54 DBS for abeta-lipoproteinemia

55 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.

56 “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

57 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?

58 What improves with DBS? Depends on site of stim but the following generally improve to varying degrees: Tremor (resting and action) RigidityBradykinesiaDyskinesias Active > fixed dystonia Motor fluctuations

59 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)

60 What may worsen? Speech (often partly reversible) Balance/ataxia(reversible) Mood (reversible but prescreen for SI) Weight(common) Dystonia (uncommon)

61 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

62 N=96 STN, 36=GPi NEMJ 2001;345:956-963

63 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

64 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

65 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

66 Tools of the Trade

67 Lead Location Directly Influences Programming: STN Thalamus Substantia nigra dorsal lateral medial ventral Paresthesias & other sensory phenomena diplopia,other oculomotor disturbances, mydriasis affective changes muscular contractions, dysarthria Reduction of rigidity, tremor, akinesia/bradykinesia, inductin of dyskinesia STN GPi

68 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.

69 Proper STN Lead Placement

70 STN LEAD PLACEMENT

71 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

72 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

73 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

74 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.

75 PD PROGRAMMING VIDEO See Video 2

76 Programming around capsular side effects

77 Initial Programming Summary C+0-2.5/60/145 chin pulling C+1-3.5/60/145 mild pull, no change C+2-3.5/60/145 subtle pull, no change C+3-3.5/60/145 no change, well tol. ---------------------------------------------------------------------- C+2- 2.5/90/145 chin pulling, no change C+3- 3.5/90/145 no change, well tol 1+2-3.5/90/145 mild improvement, well tol 0+1-2-3.0/90/145tremor improved, well tol

78 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

79 When to return after initial programming? Generally 2-4 weeks for 2 nd 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

80 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

81 INITIAL PROGRAMMING Left IPG (PW60/F145) C+0-good tremor/rigidity reduction by 2.5 C+1-good tremor/rigidity reduction by 1.5-2 C+2-slightly less improvement but good at 2 C+3-no SE, improved tremor> rig Right IPG (PW60/F145) C+0- little baseline sx w/o much change, good tol C+1-same C+2-perhaps improvement of mild rig at 2 C+3-little change, well tol to 3.5

82 INITIAL PROGRAMMING Left IPG (PW60/F145) C+0-good tremor/rigidity reduction by 2.5 C+1-good tremor/rigidity reduction by 1.5-2 C+2-slightly less improvement but good at 2 C+3-no SE, improved tremor> rig Right IPG (PW60/F145) C+0- little baseline sx w/o much change, good tol C+1-same C+2-perhaps improvement of mild rig at 2 C+3-little change, well tol to 3.5

83 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.

84 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

85 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- 1.2/60/145R: C+2- 2.1/60/145

86 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)!

87 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

88 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)

89 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.

90 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

91 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-

92 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

93 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

94 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

95 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-

96 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

97 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

98 Interleaving See interleaving graphic

99 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

100 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

101 Interleaving sample Setting A: ventral stim Setting C: dorsal stim

102 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

103 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

104 The challenging case… Sudden loss of efficacy –Check IPG’s both ON, not end of battery life? –Hardware malfunction? –Change in underlying condition?

105 The Impedance Test Usual range Short circuit Open circuit Current 25-150 microamps > 250 microamps <7 microamps Impedance500-1500 < 50 ohms > 2000 ohms If unsure, can contact Medtronic technical support: 800-707-0933

106 Images of lead fracture Garg et al, 2010

107 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.

108 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!

109 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

110 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

111 Thank You! Feel free to follow-up with emails: Michael.Pourfar@NYUMC.org Please remember to leave feedback on how we can improve for future sessions. Happy Programming! Happy Programming!


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