The gross anatomy of the cranial cervical ganglion in the guinea pig (Cavia porcellus).

The right and left cranial cervical ganglia in the heads of 10 adult guinea pigs (5 male, 5 female) were dissected in detail. The cranial cervical ganglion (CCG) was located on the caudo-ventral aspect of the distal ganglion of the vagus nerve, and medial to the digastric and styloglossal muscles. It was present also ventral to the tympanic bulla, ventro-lateral to the longus capitis muscle, and between the ascending pharyngeal and the internal carotid arteries. The branches of the CCG included the internal and external carotid nerves, the jugular nerve and connecting branches to the pharynx, vagus, glossopharyngeal, accessory, cranial laryngeal, first and second cervical nerves, and vessels in the carotid body region. The number of nerves ramifying from the CCG of the guinea pig varied among cases. Compared to other species, there are also differences in the number of nerve branches and the course patterns. No sex differences are present as far as the guinea pig CCG is concerned.