Little is known regarding the safety of electroconvulsive therapy (ECT) in the presence of cranial metallic objects (cMO) such as medical devices or metallic foreign bodies. The presence of cMO raises 3 theoretical concerns toward the safety of ECT: (1) cMO may significantly alter the ECT-induced electric field distribution in the brain regarding field strength and focality, (2) vascular complications at the location of the cMO due to the ECT-induced hyperdynamic state may occur, and (3) possible development of a prolonged seizure/status epilepticus during ECT as a consequence of a device-induced symptomatic epilepsy. In the light of missing systematic approaches, we intended to assess the safety of ECT in the presence of cMO with particular regard to the concerns as specified previously.
A systematic review of previously published cases of ECT in patients with cMO was conducted.
We identified 23 publications reporting 24 cases of ECT in the presence of cMO (cerebral clipping systems, 8 cases; cerebral coils, 2 cases; deep brain stimulator, 4 cases; osteosynthesis materials or other metallic medical devices, 7 cases; foreign bodies, 3 cases). Modified placement of ECT-electrodes was reported in 10 cases (42%). No ECT-related complications with regard to the proposed theoretical concerns were reported.
The absence of cMO-related complications during ECT in the reported cases implies that cMO might not represent an absolute contraindication for the performance of ECT. However, the indication for ECT should be put in place thoroughly in patients with cMO. Further research is necessary for an adequate safety assessment.