Dear Sir The article by Peres et al. (1) attempted to reproduce the studies done by Anthony in 1984 (2) to study the effect of greater occipital nerve block on cluster headache. Unfortunately neither of these studies used controls. The only definite way of proving that it was the blockade of greater occipital nerve and not the therapeutic effect of steroids that produced the reduction in headache frequency will be to give the control subjects injections of the same dose of steroids in a location other than the greater occipital nerve.
Anthony's patients had a better response probably because he used a different type and dose of steroids, namely 120 mg of prednisolone instead of the 40 mg triamcinolone used by the present authors.
N. Vijayan, University of California Headache Clinic, Department of Neurology, 4860 Y Street, #3700, Sacramento, CA 95817, USA.
References
1.
PeresMFPStilesMASiowHCRozenTDYoungWBSilbersteinSD.Greater occipital nerve blockade for cluster headache. Cephalalgia2002; 22: 520–2.
2.
AnthonyM.Arrest of attacks of cluster headache by local steroid injection of the occipital nerve. In:RoseC, editor. Migraine.Proceedings of the 5th Int. Migraine Symposium, London 1984. : Krager, 1985: 169–73.
