Deep transcranial magnetic stimulation in the treatment of OCD: Comparison of treatment with Double-Cone and H7 coil
M. Jakubec, O. Laskov, N.-A. Böhmová, N. Biačková, A. Čechová, T. Novák, M. KlírováIntroduction
Obsessive–compulsive disorder (OCD) is a chronic neuropsychiatric illness characterized by intrusive thoughts (obsessions) and repetitive acts (compulsions). Hyperactivity within the medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC) , structures in the cortico-striato-thalamo-cortical (CSTC) loop that affect inhibitory control , has been implicated in its pathophysiology (Zhang et al. Front Psychiatry 2019; 10 522). Deep transcranial magnetic stimulation (dTMS) is a modern variation on non-invasive brain-stimulation (NIBS) that, unlike other NIBS approaches, targets deeper cortical structures to alleviate OCD symptomatology (Laskov & Klírová Neurosci Lett 2021; 755 135906). Its efficacy has been proven in several RCTs and meta-analyses (Trevizol et al. J ECT 2016; 32 262-266; Cruz et al. Psychiatry Res 2022; 317 114869; Carmi et al. Am J Psychiatry 2019; 176 931-938).
Objectives
Two dTMS coils cleared by the US FDA for OCD are available – The BrainsWay H7 coil and the MagVenture Cool D-B80 Double-Cone coil . The Double-Cone coil, approved in 2020 for adjunctive treatment, is electromagnetically less potent in OCD-associated brain structures stimulation than H7 (Tzirini et al. PLoS One 2022; 17 e0263145). We compared the clinical performance of these two coils in a preliminary analysis of an ongoing randomised, sham (placebo)-controlled study designed to identify neurobiological predictors of dTMS response.
Methods
Twenty DSM-5-diagnosed OCD patients underwent six weeks of dTMS. Ten received the Double-Cone stimulation [active n = 8, sham n = 2] and ten the H7 stimulation [active n = 8, sham n = 2] ( Figure 1 ). Treatment response was defined as ≥ 35% reduction on the Yale–Brown Obsessive Compulsive Scale (Y-BOCS).
Results
The
highest responder rate
occurred with
active H7 stimulation
(4/8;
50%
), followed by active Double-Cone stimulation (1/8; 12.5%); no sham-treated patient responded (
Figure 2
). χ² tests showed no significant differences between coils (χ² = 2.50, p = 0.114) or between active and sham stimulation (χ² = 2.78, p = 0.095).
Mean reduction in Y-BOCS
(indicates improvement) was greatest in
H7-active
(
19.5%
), followed by H7-sham (16.2%), Double-Cone-sham (12.2%), and Double-Cone-active (4.7%).
Figure 3
shows boxplots of percentage Y-BOCS reduction by study group. Logistic regression identified
shorter OCD duration
as a significant
predictor of response
(B = −0.12, p = 0.048).
Younger age
also favoured response (p = 0.071). Although type of stimulation and coil both favoured the H7 coil, these effects did not reach significance (p = 0.086 and p = 0.059, respectively).