Insufficient blood supply from vertebral arteries. The vertebral arteries mostly originate from the posterior superior wall of the subclavian artery, enter the transverse foramen of the bilateral cervical vertebrae upward, and merge into the basilar artery after exiting the transverse foramen of the first cervical vertebra into the skull. The vertebrobasilar artery accounts for 2/3 of the cerebral blood circulation and mainly supplies blood circulation to the brainstem and occipital visual area. The vertebral artery curves backward after exiting the first cervical transverse foramen, wraps around the neck, cuts above the lateral mass and posterior arch, and then enters the foramen magnum. Here the vertebral artery bends more and is prone to trauma. Misalignment of the cervical joints predisposes the vertebral artery to traction, stimulation, spasm or compression, resulting in inadequate blood supply to the vertebral artery and ocular symptoms in patients. Involvement and stimulation of the superior cervical sympathetic ganglion or the trigeminal spinal tract. The posterior fibers emanating from the superior cervical sympathetic ganglion are distributed in the eye and carotid plexus. It regulates the ocular circulation and pupillary dilator muscle, the eyelid muscle. The superior cervical sympathetic ganglion is located in front of the transverse processes of the cervical vertebrae l to 3. When the superior cervical vertebrae are misaligned, the transverse processes are also shifted, which can involve and stimulate the superior cervical sympathetic ganglion, thus causing symptoms in the eyes and the five senses. The trigeminal spinal cord bundle in the cervical medulla can also be stimulated by atlanto-occipital joint misalignment, causing periocular neuralgia or prefrontal pain. Insufficient blood supply to the vertebral artery is the main cause of damage to the visual center or cerebral nerves.