Atlas Stim Headbox (NK) (31-0601-0077); Atlas Stim Headbox (Touchproof) (31-0601-0089); Atlas Stim Headbox (HD) (31-0601-0132); ASHB FIBER OPTIC DUPLEX CONN 2m (31-0204-0001); ASHB FIBER OPTIC DUPLEX CONN 7m (31-0204-0002); ATLAS Stim Headbox Software (36-0301-0006); Atlas Headbox Interface Cable (NK) (31-0204-003); Atlas Headbox Interface Cable (Touchproof) (31-0204-004); Atlas Headbox Interface Cable (HD) (31-0204-005); Atlas Headbox Expansion Panel (31-0607-0014)

The ATLAS Stim Headbox is a low-power, constant current or voltage bi-phasic stimulator designed for cortical or intracranial electrical stimulation during stereoEEG examinations. It works with third-party electrodes to apply stimulation to the brain and record resulting neural potentials. The device operates as an accessory to the ATLAS Neurophysiology System and requires connection to the Pegasus software; it cannot function as a standalone stimulator.

The subject device supports 32 simultaneous stimulation channels (versus 2 for the primary predicate and 16 for the secondary), with a maximum charge of 20µC per phase and pulse duration up to 5000µs. It includes a software-based safety rule requiring zero net current across all channels at any instant, limiting total current to less than 25mA. The device also features impedance checking (100Ω to 5MΩ) and operates in constant current mode with ±12.5V compliance in two ranges (±10mA and ±200µA).

IEC 60601-1:2005 ed.3+A1;C1:2014 (electrical safety), IEC 60601-1-2:2014 (EMC), IEC 60601-1-6:2010+AMD1:2013 (safety), IEC 62304:2006 (software lifecycle), IEC 62366:2007 (usability), IEC 80601-2-26:2019 (evoked response stimulators), and IEC 60601-2-40:2016 (particular standard for electroencephalography). Testing included electrical safety, mechanical integrity, evoked response, electroencephalograph, and software regression testing.

The device is substantially equivalent because it shares the same fundamental indications for use (cortical/intracranial stimulation during stereoEEG), serves the same patient population, and operates on identical scientific principles as the predicates. Although the subject device offers increased channel capacity and longer pulse durations, these differences do not raise safety concerns because the charge-limiting safety rule (20µC per phase maximum) ensures equivalent or greater safety margins than the predicates. Verification and validation testing demonstrated performance parity with predicates across electrical safety, mechanical integrity, and evoked response parameters.