ACCELEROMETRY DURING ACCELEROMETRY DURING ABLATIVE THALAMIC SURGERY FOR ABLATIVE THALAMIC SURGERY FOR

PARKINSONIAN TREMORPARKINSONIAN TREMOR

Authors:

J. Ciurea V. Nestianu*, Ileana Simoca, Dept. of Neurosurgery, University Hospital “ Bagdasar

Arseni”, Bucharest, Romania* Dept. of Neurophysiology, University of Medicine

Craiova, Romania

OBJECTIVEOBJECTIVE

• Tremor assessment during thalamotomy for Parkinson disease under the effects of electrical stimulation

• Comparison accelerometer vs. neurologist assessment

PATIENTS AND METHODPATIENTS AND METHOD

• Total number of patients: 8• Stereotactic target

– Vim

• Gender: 5 men and 3 women. • Age

– The mean age was 52 years – Range between 32 to 68 years. All patients exhausted drug therapy or did not

respond or tolerate it.

PATIENTS AND METHODPATIENTS AND METHOD

• The following parameters were recorded during electrical stimulation of the target :

• Frequency (Hz) • Amplitude• Occurrence of tremor • Comparison with neurological direct observation. • The lowest stimulation tremor suppression electrical

threshold was used to select the optimal lesion site.

RESULTSRESULTS

• Improvement:– United Parkinsonian Disease Rating Scale– Schwalb & England Scale – Hohen & Yahr Score.

Tremor:

Rest

Positional

Intention

DEEP BRAIN ELECTRICAL STIMULATIONDEEP BRAIN ELECTRICAL STIMULATION AND TREMOR AND TREMOR

• Monitoring:– EMG

• + standardized clinical tool• - only groups of muscle and movements can affect the position of the

electrode– Acceleromerter

• + vectorial components of movement• - the amplitude is a derivate and depends of frequency

– Optical – photocouple - diode and receiver • +simple • - only frequency, interference with other sources

– Piezo• +sensitive• -frequency response dependent on “crystal resonance”

– Video+ state of art-three simultaneous cameras and a analysis soft, retrospective

DEEP BRAIN ELECTRICAL STIMULATIONDEEP BRAIN ELECTRICAL STIMULATION AND TREMOR AND TREMOR

• The 2 - 100 Hz stimulation

EFFECT OF STIMULATIONEFFECT OF STIMULATION

WATERFALL PRESENTATION OF WATERFALL PRESENTATION OF ELECTRICAL STIMULATION EFFECTSELECTRICAL STIMULATION EFFECTS

REST TREM OR +LOAD

0

20

40

60

80

100

120

1 77 153 229 305 381 457 533 609 685 761 837 913 989 1065 1141 1217 1293 1369 1445 1521 1597 1673

t (1=0.03 sec.)

AU Ampl.

Accelerometer vs. ObserverAccelerometer vs. Observer

Accelerometer sy. identification - earlier than Accelerometer sy. identification - earlier than clinical observerclinical observer

CONCLUSIONCONCLUSION

– IS TREMOR MONITORING NECESSARY?– IS TREMOR MONITORING USEFUL?

• TREMOR MONITORING IS AN OBJECTIVE AND

EFFICIENT METHOD.