It was reported the physician has a patient with dystonia who is experiencing intermittent out of regulation (oor) error messages on his patient programmer (pp).The patient is also seeing his implantable neurostimulator (ins) voltage go up and down by several 10ths of a volt, which suggests that his therapeutic impedance is fluctuating, resulting in variable therapeutic current draw.The patient was seen in clinic yesterday and it was observed that in some situations, sometimes by placing the ins under downward traction, they could induce a high impedance at contacts 2 and 3 as follows: dbs settings are c+ 1-3-, 90 s, 130 hz.Normal therapy impedance 680 ohms, 3.9 ma and normal monopolar and bipolar electrode impedances.At times the impedances are elevated: c-2: 2629 ohms, 1-2: 6086 ohms and c-1: 2600, c-2: 3000 the physician inquired about what specific circumstances trigger an oor error message on the pp.They want to make sure they have identified the problem before discussing whether surgical repair is necessary.The patient's ins is programmed in constant voltage mode and does not think that impedance increasing to 2700 ohms would cause an oor.They have observed previous patient's with lead fractures that even a full interruption of the circuit would not trigger oor in constant voltage mode.It was reviewed that if the patient is programmed in constant voltage, then shorts or low impedance causes oors.
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