The methods to detect the fusion pore

According to my knowledge there are at least 3 ways to detect the fusion pore.

1) Amperometry method (foot signal before the main spike) to detect the transmitter leaking from the fusion pore. 
2) Patch-clamp measurement to detect the fusion pore formation by tracking the conductance
change of the fusion pore.
3) Image. Electro-microscope image and AFM were used to image the fusion pore.