Understanding the Charge Density Warnings
The Clinician Programmer software provides several warnings when the charge density at a
contact may exceed 30 microcoulombs/cm
damage above this level. The graph below displays the recommended maximum charge density of
30 microCoulombs/cm
for different combinations of current amplitude (mA) and pulse width (µs)
2
for Boston Scientific DBS Leads.
The Clinician Programmer software provides a warning when the charge density at a contact is
about to be programmed to exceed 30 microcoulombs/cm
Clinician Programmer allows the stimulation to continue above this level. The warning reads:
"CAUTION: Charge density limit reached. Continue programming at your discretion."
Note: A charge density limit warning will be displayed on the Programming screen while
any area is above the charge density limit and will clear when all areas are below it.
A warning is also displayed when the amplitude range of a program exceeds charge density limits.
The warning reads:
"Caution: With present settings, the patient could exceed the charge density limit with
the remote control. Continue programming at your discretion."
Another warning is displayed when a program that is capable of exceeding the charge density limit
is saved to a program slot in the patient's Remote Control. The warning reads:
"Caution: Charge density limit may be reached with the current Max mA set. Do you
want to continue?"
per stimulation phase, as there is evidence of tissue
2
30 uC/cm
2
Pulsewidths (usec)
per stimulation phase. However, the
2
Programming the Patient
Vercise™ DBS Programming Manual
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