Arterial supply of the trigeminal ganglion, a micromorphological study

BACKGROUND: In this study, we explored the specific microanatomical properties of the trigeminal ganglion (TG) blood supply and its close neurovascular relationships with the surrounding vessels. Possible clinical implications have been discussed. MATERIALS AND METHODS: The internal carotid and maxillary arteries of 25 adult and 4 foetal heads were injected with a 10% mixture of India ink and gelatin, and their TGs subsequently underwent microdissection, observation and morphometry under a stereoscopic microscope. RESULTS: The number of trigeminal arteries varied between 3 and 5 (mean 3.34), originating from 2 or 3 of the following sources: the inferolateral trunk (ILT) (100%), the meningohypophyseal trunk (MHT) (100%), and from the middle meningeal artery (MMA) (92%). In total, the mean diameter of the trigeminal branches was 0.222 mm. The trigeminal branch of the ILT supplied medial and middle parts of the TG, the branch of the MHT supplied the medial part of the TG, and the branch of the MMA supplied the lateral part of the TG. Additional arteries for the TG emerged from the dural vascular plexus and the vascular network of the plexal segment of the trigeminal nerve. Uniform and specific intraganglionicdense capillary network was observed for each sensory trigeminal neuron. CONCLUSIONS: The reported features of the TG vasculature could be implied in a safer setting for surgical approach to the skull base, in relation to the surrounding structures. The morphometric data on TG vasculature provide anatomical basis for better understanding the complex TG blood supply from the internal and external carotid arteries.