Objective Although a lot of people have recently reported headaches provoked after watching 3-D videos, the clinical features of the so-called "3-D headache" have not been clarified. In this study, we investigated the clinical features of headaches provoked after watching 3-D videos.
Methods We conducted a questionnaire survey by email to cases who described headaches caused by watching 3-D videos on a Weblog. We established the diagnostic criteria for 3-D headaches, which are as follows for a definite 3-D headache: A) Provoked after watching 3-D videos, but was never provoked by 2-D videos, B) Never experienced previously, C) Unclassifiable by the ICHD-II. A possible 3-D headache was one that met the criteria of A) and B) the same as above, C) Classified as a "probable" subform by the International Classification of Headache Disorders-2nd Edition (ICHD-II).
Results We received answers from 16 cases (5 males, 11 females, average age of 35.8 years old). Eleven of the 16 cases had experienced an entirely new type of headache after watching 3-D videos. Of these 11 cases, 5 were diagnosed as having a definite "3-D headache". The other 6 cases were diagnosed as having possible 3-D headaches. The remaining 5 of 16 cases were suspected to be attacks of primary headaches that the cases were accustomed to having experienced. The common characteristics of the 5 definite 3-D headaches were that they were bilateral and non-pulsating, and the duration was from 10 minutes to 24 hours. The intensity of the 3-D headache was as follows; severe in 2 cases, moderate in 2 cases, and mild is one case. Three of the 4 cases with moderate to severe headache had nausea.
Conclusion The headaches provoked after watching 3-D videos include not only the attacks of primary headaches but also the headache attacks unclassifiable by the ICHD-II.
2012 by The Japanese Society of Internal Medicine