High-frequency repetitive navigated transcranial magnetic stimulation in the treatment of

central post-stroke pain

A.V. Chervyakov, A.G. Poydasheva, N.A. Suponeva, L.A. Chernikova, M.A. Piradov

Berlin, 12.10.2022

Research Centre of Neurology Russian Academy of Medical Science

IntroductionCentral post-stroke pain (CPSP) is a syndrome that appears after lesions in central parts of the somatosensory system.

A total of 10% of post-stroke patients experience CPSP, and pharmacological treatment often remains insufficient.

Aim

to assess the efficacy of high-frequency repetitive transcranial magnetic

stimulation (rTMS) and the neurophysiological

characteristics of cortical excitability before and after stimulation in patients with

CPSP

DesignRandomized blind sham-controlled study

Inclusion Criteria:

Exclusion Criteria:

•Ischemic or hemorrhagic stroke. • Drug resistance CPSP.

implanted pacemaker, intracardiac catheters, electronic pumps, pregnancy or possibility of pregnancy in women of childbearing age (before menopause), according to a pregnancy test; presence of metallic elements or implants in the head region, located closer than 20 cm from the edge of the surface coil magnetic stimulator, with the exception of the mouth; epilepsy or seizures in history, epileptic discharges on EEG.

DesignResearch groups

Group 1 (experimental).High frequency stimulation: 10

Hz, 80% MT, 2 seconds - stimulation, 58 seconds – rest; affected hemisphere (M1, APB).

Group 2 (control).Sham stimulation

n=12; mean age – 56,06±8,84, 20,07±33,49 mouths after stroke

MA – 59,80±8,40 y., Duration of CPSP – 71.9 ± 46.0 m.

MA – 52,30±7,10 y., Duration of CPSP – 69,00 ± 45.00 m.

N=7 n=5

10 times - 10 min

10 Hz, 80 % MT

200 stimulus

2 sec 58 sec Sham - stimulation

For nTMS used NBS eXimia Nexstim and Magstim Rapid2. Clinical condition of patients was assessed with a sets of scales

before and after stimulation.

10 times - 10 min

200 stimulus

Design

Clinical scaleVisual analogue scale - pain: 0 (no pain) to 10 (extreme pain)

Neurophysiological measured

Motor evoked potential (MEP) amplitude

MEP latency

Motor threshold

Magnetic field strength

Motor cortical area

Results (VAS)

Sham 10 Hz

-6-4-20246810

78

6

3

-1

-5

Before After Diff

*

Responders Nonresponders0123456789

78

2

7

Before After

*

p = 0.03

28%

Results (Neurophysiological measures)

Motor treshold Magnetic field strength

01020304050607080

46

62.550

78.5

Before After

Before After0

200400600800

10001200140016001800

1573.5

614.5

MEP Amplitude

Results

Decrease of the cortical area square

VAS 8

10 rTMS sessions

VAS 1

3 weeks

VAS 3

VAS 8

3 months

VAS 8

Post-stroke pain

Stroke 20.08.2003

Pharmacological treatment

Hospitalization 25.07.2012

10 rTMS sessions

Hospitalization 02.04.2013

Case 1. Patient K, 59 years old, subcortical

VAS 5

10 rTMS sessions

VAS 2

4 months

VAS 8

VAS 2

Post-stroke pain

09.2003

Stroke 28.03.2003

Pharmacological treatment

Hospitalization 16.02.2013

10 rTMS sessions + stop drug treatment

04.07.2013 - Ambulence

Case 2. Patient A, 41 years old, cortical

ConclusionHigh-frequency M1 rTMS could be used in the treatment of CPSP syndrome;

The mechanisms underlying the observed changes in cortical excitability remain unclear and possibly indicate the presence of a pathological pain system;

One of the important goals for future studies is to reveal the neurophysiological predictors of the therapeutic insufficiency of rTMS in patients with CPSP. 

Thanks a lot for your attention!

Acknowledgments

Michail Piradov

Ludmila Chernikova

Victor Gnezditsky

Natalia Savitskaya

Pavel Fedin

Rodion Konovalov

Maria Nazarova

Sofia Kulikova

Alexandra Poydasheva

Konstantin Latyshev

Research Center of Neurology Russian Academy of Medical Science

www.neurology.ruwww.brain-stim.ru