Table 2.

Recording of symptoms after triggering with GTN

A	B
Time points after GTN infusion initiation	Symptoms queried at each time point
-5	Headache details – side, site, type
0	Nausea
5	Photophobia
10	Phonophobia
15	Tiredness
20	Neck Stiffness
25	Yawning
30	Mood Changes
35	Urination
40	Cravings
50	Thirst

Recording of symptoms was continued at 10–15 minute intervals until all scans were complete.