Deep transcranial magnetic stimulation in patients with intracranial aneurysm clips: A case report and guidelines for clinicians

While some experts consider intracranial aneurysm clips a contraindication to TMS [1], others view such clips as potentially surmountable obstacles to treatment IF the clips are constructed of non-ferromagnetic titanium [2]. We present a case of severe treatment-resistant major depression successfully treated with deep TMS, followed by conventional TMS, in a patient status-post a ruptured cerebral aneurysm treated with a titanium aneurysm clip. We summarize guidelines from the MRI literature supporting the use of TMS in patients with titanium aneurysm clips. Although caution is warranted, an absolute contraindication surrounding aneurysm clips in TMS patients may cause more harm than good by pre-empting access to TMS by patients who might otherwise benefit from TMS treatment. Saxby Pridmore and Fiona Lawson demonstrated that non-ferromagnetic aneurysm clips do not significantly move when subjected to pulses from a figure8 coil, even held at unrealistically close distances [3]. We performed an analogous trial with a Brainsway H-1 coil device with similar results. Additionally, patients with nonferromagnetic intracranial aneurysm clips have been undergoing MRI’s safely for decades. With the field strength of even deep TMS coils being roughly equivalent to current MRI machines, TMS should be safe in patients with non-ferromagnetic aneurysm clips. We treated a 73-year-old womanwho suffered a ruptured aneurysm at the age of 53 that was treated with a titanium aneurysm clip. Persisting balance, memory, and executive function impairment, as well as a treatment-resistant depression, followed her aneurysm. Previous unsuccessful medication trials included 5 SSRI’s and 2 TCA’s augmented with 4 atypical antipsychotics, triiodothyronine, buspirone, lithium, bupropion, lamotrigine, pramipexole, methylphenidate, mixed amphetamine salts, atomoxetine, dextroamphetamine, amantadine, and trials with two MAOI’s. She underwent 30 sessions of deep TMS with a Brainsway device using 1 Hz slow stimulation to the right dorsolateral prefrontal cortex (DLPFC) followed by intermittent theta burst stimulation (iTBS) to the midline prefrontal cortex. She also underwent an additional 34 treatments at another TMS treatment center using a Neurostar figure8 coil with fast 10 Hz stimulation over the left DLPFC and slow 1 Hz stimulation over the right DLPFC. The patient tolerated deep TMS without complications (her longstanding migraine headaches worsened initially but then markedly improved by week 4 of deep TMS). Her BDI-II score dropped from 39 to 16, her PHQ-9 score dropped from 27 to 13, and her Beck Anxiety Inventory (BAI) score dropped from 20 to 7. The patient showed additional improvement on the PHQ-9 after 34