Evoke
®
SCS System Clinical Manual
CLIN-UMAN-005175
Revision: 9.00
Page 31 of 101
Table 6.1: Guidelines for setting appropriate limits and increments for stimulation current
and ECAP target.
Parameter
Guideline
Maximum Current
Limit (mA)
(see Section 8.1)
Set to the first available value
!
1.5 x stimulation current at the
Maximum activation plot level, measured while the patient is in the
sitting posture (see Section 7.6).
ECAP Target
Maximum (µV)
(see Section 8.2)
Set to the first available value such that the ECAP Target Maximum
> Maximum/1.5 and ECAP Target Maximum > , (where
Maximum and refer to the activation plot levels measured
while the patient is in the sitting posture, see Section 7.6).
ECAP Minimum (µV)
(see Section 8.6)
Set to the highest value such that the ECAP Minimum ≤ minimum
ECAP amplitude recorded during collection of the activation plot
and posture testing (see Section 7.6).
ECAP Target
Minimum (µV)
(see Section 8.6)
Link to ECAP Minimum, or if necessary, de-link and set to the
highest value such that the ECAP Target Minimum ≤ ECAP amplitude
at the ECAP threshold (see Section 7.6).
Current Increment
(mA)
(see Section 8.1)
Set between 0.1 and 0.3 mA, depending on the current range
between Threshold and Maximum activation plot levels in the
sitting posture (see Section 7.6). Increase the increment if each step
has no noticeable change in intensity for the patient, and decrease
the increment if there is too large a change in intensity.
ECAP Target
Increment (µV)
(see Section 8.2)
Set to the value closest to /10 (where refers to
the activation plot level measured while the patient is in the sitting
posture, see Section 7.6).
6.13
Enable closed-loop stimulation
Once all the settings for the program have been set up and the criteria for the activation plot
have been met (see Section 6.11), you may evaluate closed-loop operation. It is important to
test the effectiveness of the closed-loop control with the patient in various postures.
1. Start stimulation and set the current to a comfortable level.
2. Touch the
CL
icon
to enable closed-loop stimulation (see ECAP amplitude bar in
Figure 6.2).
3. When closed-loop is enabled, the rolling plot will display with an orange background and
the current will vary over time (Figure 6.20). The ECAP amplitude will vary around the
target level (Figure 6.22). If the ECAP variability is increased after closed-loop is enabled:
a. You may increase the Patient Sensitivity setting (see Section 8.2) to reduce this
