Following the work carried out between Micromed SW engineers and Meyer researchers, a first release of the program HFO Annotation Tool (HAT) was released at the beginning of June 2014. It interacts with MICROMED SystemPlus (from which it is launched) in order to analyses a selected EEG file. After the release some requests were done by the Meyer research team:

• synchronized split-screen, i.e. the possibility to review the EEG trace with the same derivations in two windows tiled horizontally or vertically and with different base-times and filters; in one window longer base-time (10 sec) and "standard" filtering (for example IIR 0.16 - 70Hz for all traces) and in the other shorter base-time (1.5 sec) and HFO filtering (FIR 100 - 200 Hz, 250 - 500 Hz, etc.); navigation must be kept synchronized between the two windows;
• possibility to insert a new kind of events, the "GAMMA" events (FIR 40 - 80 Hz) together with Spike, HFO Ripple, HFO FastRipple, that are already present;
• add the base-time of 1.5 sec;
• manage multi-user interface: possibility to show/hide the events inserted by a user;
• management of derivations like SystemPlus: the user can select a pull of lines to keep among the whole montage; possibility to reload the montage in a click;
• possibility to view a panoramic of the events inserted in the horizontal scrollbar used for the navigation.