H. Angusleppan et al., CONVERGENCE OF OCCIPITAL NERVE AND SUPERIOR SAGITTAL SINUS INPUT IN THE CERVICAL SPINAL-CORD OF THE CAT, Cephalalgia, 17(6), 1997, pp. 625-630
Co-existence of facial and occipital pain may occur in occipital neura
lgia, migraine and cluster headache; suggesting convergence of trigemi
nal and cervical afferents. Such convergence has been shown in humans
and other animals, but the site and extent of this are uncertain. In a
naesthetized adult cats, the superior sagittal sinus and occipital ner
ve were stimulated electrically and extracellular recordings made in t
he dorsolateral area of the upper cervical cord using glass-coated tun
gsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the
superior sagittal sinus and the occipital nerve. Thirteen (27%) had su
perior sagittal sinus input and 3 (6%) had occipital nerve input. Conv
ergent receptive fields were identified mechanically in 7 units. These
experiments in cats show convergent input from occipital nerve and su
perior sagittal sinus on dorsolateral area units in two-thirds of case
s studied. This experimental site of trigeminocervical convergence may
relate to referral of pain in occipital neuralgia and other headaches
.