Figure 2. The helmet sign is named after Prussian helmet shown in the image [24]

From

Helmet Sign on EKG: A Rare Indicator of Poor Prognosis in Critically Ill Patients

Fatai Oluyadi, Pramod Theetha Kariyanna, Apoorva Jayarangaiah, Jessica Celenza-Salvatore, Isabel M. McFarlane

American Journal of Medical Case Reports. 2019, 7(10), 260-263 doi:10.12691/ajmcr-7-10-9