My ex-wife suffered from this on a Delta 727-200 DEN-DFW a few years back. She had a sinus infection that she didn't even know about, but when we were on final to DFW she tapped me on the shoulder and had the most horrible look on her face. I didn't know what to do except push the call button, and fortunately the Delta FA knew exactly what to do: she climbed over me and held her thumbs tight against my ex's forehead until we were on the ground. For the rest of the day my ex said she felt like she'd been hit with a hammer. Daze