Boston Scientific Vercise DBS Mode D'emploi page 81

4. Determine the area with the largest amplitude.
Largest amplitude = __________ mA
5. Look up the battery-longevity projection in the table using the Total Rate,
TWPW, and largest amplitude. (Interpolation may be used for improved
accuracy.) The battery-longevity projection is given in years and represents the
longevity of a typical rechargeable Stimulator battery when used continuously.
If the rechargeable Stimulator battery is not used continuously, the battery-
longevity should be greater than the value given.
Multiple-Area Battery Longevity Worksheet Example 1
In this example two stimulation areas are used with the following settings:
Area 1:
Amplitude = 3.0 mA, Rate = 130 Hz, PW = 60 µs
Area 2:
Amplitude = 3.0 mA, Rate = 185 Hz, PW = 90 µs
1. Calculate the TOTAL RATE (TR) of the stimulation frequencies by adding
together the rate from each area that is used:
TOTAL RATE = Rate 1 130 Hz + Rate 2 185 Hz
TOTAL RATE = 315 Hz
2. Calculate the Rate Weighted Pulse Width (RWPW) for each area used by
multiplying the pulse width value for each area used by the Rate of that area and
then dividing the result by the TOTAL RATE that was previously calculated.
RWPW1 = PW1 x Rate 1/ TOTAL RATE
= (60 x 130)/315 = 24.76
RWPW2 = PW2 x Rate 2/ TOTAL RATE
= (90 x 185)/315 = 52.85
3. Calculate the Total-Weighted Pulse Width (TWPW) by adding the rate weighted
pulse widths.
TWPW = RWPW 24.76 + RWPW2 52.85
TWPW = 77.61 µs
Appendix
Physician Manual
91098825-07 Rev A 77 of 333