No deformation was observed at Fuego (detection threshold 5.1 cm/yr) during an ALOS survey of Central American volcanoes (Ebmeier et al., 2013). Lack of deformation despite continuous eruption over this period is explained by Fuego having an open conduit system which doesn’t pressurise over long time periods.
Broadband seismometers have been used to detect inflation and deflation associated with strombolian explosions (Lyons et al., 2012). The tilt is interpreted to show inflation beginning 20-30 minutes before the explosions, followed by deflation a few minutes prior to the explosions. The best fitting model source for the deformation is a point source  40 m below the surface and 120 m west of the summit.