Cranial Neuralgias – Symptoms of pain, smell, vision, hearing, taste and talking
Ross Hauser, MD.
This article is a companion article to the many articles on our website that focus on Cranial Neuralgias.
- Patients diagnosed with cranial neuralgias have a sharp, stabbing pain about the face and head. These pains are caused by a malfunction or dysfunction of the cranial nerves and the face. These pains are often called “paroxysms” or sudden pain attacks.
- The most common of these cranial neuralgias are: Trigeminal neuralgia, Glossopharyngeal neuralgia, Occipital neuralgia. As we will see in the discussion and research below compressive forces on the nerves through the cervical spine region may be the cause of symptoms in many people.
Our 5 senses connect our nervous system to the outside world. Vision allows us to navigate the outside world and as such, 30% of the cerebral cortex is devoted primarily to vision, whereas 8% is for touch and 3% for hearing. Cranial neuralgias can be characterized by cervical spine instability -induced sensory hypersensitivity, where normal sensory stimuli cause irritating symptoms such as hyperosmia (smell), photophobia (light/vision), hyperacusis (hearing), dysgeusia (taste) and talking/chewing (trigeminal neuralgia).1
In this article I want to expand on other articles on this website which discuss vagopathy or vagus nerve dysfunction and resultant symptoms from excessive cranial nerve outputs. That is a distortion in the messages that the nerves send and receive.
Causes of cranial neuralgia
Any of the nerves that innervate the scalp or structures in the face, head or upper cervical vertebrae or soft tissue structures can be a cause of cranial neuralgia. Cranial neuralgias are paroxysmal painful disorders of the head, mouth, face, eyes, ears and even the teeth and tongue, characterized by some shared features such as the unilaterality of symptoms, transience and recurrence of attacks, superficial and “shock-like” quality of pain, and the presence of triggering factors. The pain can be excruciating, it can come on in waves, and it can be associated with migraine headaches. On physical examination, there is evidence of allodynia and hyperalgesia. This occurs because of neurogenic inflammation and can effect not just the nerve involved but also distant nerves. The skin is often very hypersensitive to any sort of pressure. It is important to find out if the person has any previous or current neck symptoms such as pain, tightness, clicking or grinding, and if the severe head or face pain is worsened with any type of neck motion or when the neck bent over texting, reading or typing. If there is an association with the neck, then consideration has to be made that the cranial neuralgia is from upper cervical or temporomandibular instability.
What are we seeing in this image? How upper cervical instability can impact the brainstem.
The vast array of neurologic-like, vascular, and cardiovascular-like symptoms suffered by patients with suspected cervical spine instability can be explained by examining the position of the brain stem in the cervical spine and how instability at the C1 or C2 levels can cause these bones to start wandering around and compressing nerves, arteries, and veins.
Below is a list of the cranial nerves which, when impacted by cervical spine instability, can produce symptoms:
- Cranial Nerve I (Olfactory) dysfunction can produce hyperosmia – a heightened sense of smell.
- Cranial Nerve II (Optic) dysfunction can produce blurry vision, pupil dilation (light sensitivity), difficulty was gaze and visual tracking (oscillopsia), and double vision (diplopia).
- Cranial Nerve III (Occulomotor) dysfunction can produce diplopia, poor eye tracking.
- Cranial Nerve IV (Trochlear) dysfunction can produce double vision (diplopia), eye drifts upward
- Cranial Nerve V (Trigeminal) dysfunction can produce migraine headache, decreased hearing, ear fullness, dizziness (eustachian tube dysfunction), trigeminal neuralgia, severe face pain, diplopia. Trigeminal neuralgia is generally characterized by lancinating, unilateral, paroxysmal pain occurring in the distribution of the fifth cranial nerve.
- Cranial Nerve VI (Abducens) dysfunction can produce double vision (diplopia), eye drifts medial (towards the center).
- Cranial Nerve VII (Facial) dysfunction can produce sensitivity to sounds (hyperacusis), metallic taste, change in taste (hypogeusia).
- Cranial Nerve VIII (Vestibulocochlear) dysfunction can produce dizziness, sound sensitivity, vertigo.
- Cranial Nerve IX (Glossopharyngeal) dysfunction can produce Glossopharyngeal neuralgia causing paroxysms of stabbing or lancinating pain in the base of the tongue and facial region on one side and is provoked by swallowing, talking (vocal cord dysfunction) and coughing. The person gives a history of electric shock-like sensations, occurring spontaneously or evoked or worsened by innocuous stimuli (one that does not cause pain itself – like heat or a pin prick) There can be a change in taste, dizziness (dysautonomia), severe throat pain.
- Cranial Nerve X (Vagus) dysfunction can produce Postural Orthostatic Tachycardia Syndrome (POTS), dystonia, gastroparesis, dysautonomia, mast cell activation syndrome,
- Cranial Nerve XI (Spinal accessory nerve) dysfunction can produce sternocleidomastoid muscle torticollis, trapezius tension, neck tension / pain
- Cranial Nerve XII (Hypoglossal) dysfunction can produce tongue pain, tongue fasciculations.
While there are many causes of cranial neuralgias, the most commonly seen at our center are compression in the cranial nerve from:
- Cerebrospinal fluid stasis (statis being a blockage or slowdown).
- A paper published in the journal Alternative therapies in health and medicine (2) hypothesized that stasis of the cerebrospinal fluid (CSF) occurs commonly and impacts health.
- Physiologic factors affecting the normal circulation of Cerebrospinal fluid include cardiovascular, respiratory, and vasomotor influences.
- Cerebrospinal fluid appears to be particularly prone to stasis within the spinal canal.
- Cerebrospinal fluid stasis may be associated with adverse mechanical cord tension, vertebral subluxation syndrome, reduced cranial rhythmic impulse, and restricted respiratory function. Increased sympathetic tone (anxiety, stress, increased heart rate), facilitated spinal segments (hyperactive response to normal stimulation, “oversensitive nerves”), dural tension, and decreased CSF flow have been described as closely related aspects of an overall pattern of structural and energetic dysfunction in the axial skeleton and central nervous system.
- A paper published in the journal Alternative therapies in health and medicine (2) hypothesized that stasis of the cerebrospinal fluid (CSF) occurs commonly and impacts health.
Cerebrospinal fluid stasis is normally from an increase in venous pressure (venous hypertension) because of compression of the internal jugular vein. When fluid cannot properly drain from the brain, it will go to the path of least resistance, which is sometimes the cranial nerves. The inclination of the atlas (C1 vertebrae) acts a fulcrum to kink various structures, including the carotid sheath contents and vertebral artery. The constant stretching of the vertebral artery can lead to dolichoectasia, whereby the vertebral artery and its branches become distended and tortuous, with some of them encroaching on vital neurovascular structures, causing nerve compression syndromes in the posterior fossa.
- Any cranial nerve can be encroached upon by an artery or a vein at the place of the nerve’s entry or exit from the brainstem, the most common being the trigeminal, vestibulocochlear, and glossopharyngeal nerves, causing trigeminal neuralgia, vestibular paroxysmia, and glossopharyngeal neuralgia, respectively. Any cranial nerve can be encroached upon by an artery or a vein at the place of the nerve’s entry or exit from the brainstem, the most common being the trigeminal, vestibulocochlear, and glossopharyngeal nerves, causing trigeminal neuralgia, vestibular paroxysmia, and glossopharyngeal neuralgia, respectively.
The cardinal symptoms of cranial neuralgia depend largely on what structures they innervate. When pain is involved, it is often excruciating. Glossopharyngeal neuralgia, for instance, is characterized by vicious attacks of pain originating from the tonsils, tongue, or pharynx and radiating to the ear and the mandible. There can also be a loss of the gag reflex. These symptoms can be provoked by swallowing, especially cold liquids, but chewing, laughing, coughing, sneezing, and touching the ear lobe can also trigger pain. Trigeminal neuralgia has similar aggravating triggers, and its pain is described as unilateral attacks of stabbing, sheering, and lancinating from deep within the back of the throat into the face, causing a hemifacial spasm. The trigeminal nerve originates in the pons and connects with the upper 2 cervical spinal nerve roots in the trigeminocervical nucleus—in the upper spinal cord—and then travels all the way down to the C3 level.
The impact of surgery and other treatments on Trigeminal neuralgia, Glossopharyngeal neuralgia, Occipital neuralgia
These neurolgias can be caused by many different medical problems including brain lesions, progressive neurological disorder, malformation of blood vessels. In this article our focus will be on compression of the nerves and blood vessels, specifically, compression caused by cervical spine instability.
In January 2022 Dr. Jeremy C Ganz of the Department of Neurosurgery, Haukeland University Hospital, Bergen, Norway wrote in the journal Progress in brain research (9) :
“Spontaneous Trigeminal Neuralgia is a painful condition of the face which may require interventional treatment if medicines fail to control the pain. These include microvascular decompression (surgery to relieve symptoms caused by compression of a nerve by an artery or vein) and Gamma Knife® surgery is a treatment that uses radiation and computer mapping to treat brain tumors, vascular malformations and other brain abnormalities. Microvascular decompression is moderately more effective but Gamma Knife® surgery has become accepted both as an alternative to Microvascular decompression or (to be used in tandum). Like all treatments of the condition, it is successful in a majority of patients but by no means all. Repeat treatments are possible.”
Whether one is diagnosed with trigeminal, occipital or one of the cranial neuralgias, there is a variety of medication and invasive procedures such as chemoneurolysis or chemodenervations or chemical neurolysis?, radiofrequency lesioning, percutaneous ablative procedures, stereotactic radiosurgery, and open rhizotomy and microvascular decompression surgeries that are used to reduce the pain of the condition. It should be noted that some of the surgical procedures used to treat cranial neuralgias are performed in the cervical spinal cord or nerve roots, including placements of cervical and cervicomedullary spinal cord stimulation, which speaks to a cervical cause of the condition. The response of manual therapies, including manipulation in the neck in the relief of trigeminal pain, also speaks to a cervical cause.
This last point is extremely important. Any unusual painful disorder that is made worse or better with a specific kind of head or neck movement, in my opinion, is caused by cervical instability unless proven otherwise. Cervical instability affects so many structures including multiple nerves. This is why there is so much overlap in the symptoms various neck conditions cause. Consider one disorder, carotidynia that simulates the symptoms of trigeminal neuralgia. Carotidynia can cause a dull, throbbing, continuous localized pain over the carotid artery in the front of the neck but radiates pain to the ipsilateral mandible, cheek, eye or ear. The symptoms are frequently aggravated by swallowing, chewing, and contralateral head movements. The cardinal physical finding is tenderness on palpation of the carotid bulb (in the throat) and sometimes throbbing of the carotid pulse. Almost all of these patients present with head, neck or face pain. Vasoconstrictor (migraine-type) medicines work to control symptoms, but again a better option, especially if the person has neck symptoms and the primary pain is aggravated by neck movement, would be an evaluation for cervical instability. As we have discussed, upper cervical instability can stimulate the trigeminovascular system causing dilation of cerebral/facial blood vessels, resulting in pain and headache.
Cervical Spine Instability, Vein blockage, fluid build-up, and intracranial hypertension.
Pain in the head and neck is mediated by sensory (afferent) nerve fibers in the trigeminal nerve, glossopharyngeal and vagus nerves, and the upper cervical roots via the occipital nerves. Stimulation of these nerves by compression, distortion, exposure to excessive heat or cold, or other forms of irritation or by a space-occupying lesion (a tumor or mass) in the central nervous system may give rise to stabbing or constant pain felt in the area innervated. The cause can clearly be internal such as a herpes zoster infection or space occupying lesion such as a tumor, but many times the neuralgic pain is from upper cervical instability. However, the diagnosis goes missing.
Blurry vision, eye pain, eye pressure, light sensitivity and other vision problems, along with symptoms above among the more troubling and disabling symptoms that are often due to cervical spine instability. An summary and explanatory notes of this video can be found here at: Blurry vision, light sensitivity, brain fog, increased ocular pressure and cervical Instability.
Neuralgias of these nerves are rarely isolated.
Because of the proximity as they exit (or enter) the brain in the jugular foramen and travel together in the carotid sheath just millimeters from the lateral mass of C1, neuralgias of these nerves are rarely isolated. Once the Glossopharyngeal, Vagus, Spinal accessory nerve and the internal jugular vein exit the brain cavity through the jugular foramen, they pass through a narrow space for several centimeters between the transverse process of C1 and the styloid process, with the facial nerve also nearby.(3,4,5) In the anterior neck, the parasympathetic nervous system (via the vagus nerve) sends off neural branches to the Superior Cervical Sympathetic Ganglion, as well as most of the cranial nerves.(6)
Specifically, after it exits the jugular foramen, the spinal accessory nerve passes through a space between the transverse process of C1 and the styloid process, where it receives connections with the C1 nerve to innervate the sternocleidomastoid muscle. This is one explanation why spastic torticollis or cervical dystonia is commonly caused by atlantoaxial instability or C1 nerve root irritation. Other nerves have neural connections with cranial nerves through the cervical plexus, ansa cervicalis, and trigeminocervical nucleus in the upper cervical cord, such as the hypoglossal nerve (CN XII). Cervical spine instability caused by cervical liagemnt weakenss and the neural connections between the ansa cervicalis and the hypoglossal neve also explain conditions such as burning mouth syndrome, hypoglossal nerve palsy, and neck-tongue syndrome; the latter condition is assumed with neck pain and tongue numbness following quick rotations of the neck. (7,8)
Of the 300 different types of headaches and facial pains, it is agreed that dysfunction of the trigeminal nerve (CN V) is often the common denominator for many of these conditions. The trigeminal nerve is the largest of the cranial nerves and is responsible for the sensory and motor functions in the face, teeth, oral and nasal cavity, muscles of mastication, and parts of the scalp. Stimulation of the trigeminocervical nucleus (an area of the upper cervical spinal cord where sensory nerve fibers of the trigeminal nerve may interact with sensory fibers from the upper cervical roots) is thought to be the main inciting event in headache pain, including tension and migraines, as the meninges and cranial blood vessels are richly innervated by nociceptors (sensory receptors) from the first division of the trigeminal nerve. Likewise, stimulating the trigeminal nerve via chewing or other means could aggravate or cause occipital neuralgia.
Please see my article Cluster headache treatment – cervical ligament instability and the trigeminal and vagus nerves for more information on the trigeminal nerve.
The enormous neural connections of the trigeminal nerve with the sympathetic, parasympathetic, upper cervical nerves, and lower cranial nerves is why talking, chewing, and laughing can cause symptoms not attributed to the distribution of the trigeminal nerve, such as dizziness, low blood pressure, heart palpitations, and occipital headaches. The neurology of headache gets even more interesting as the distal branch of the C2 nerve—the greater occipital nerve—has neural connections with the trigeminal nerve.
Cervical instability irritates the C2 ganglion
The caption of the illustration below reads: The superior cervical sympathetic ganglion’s close proximity to the vagus nerve. The superior cervical sympathetic ganglion sits right in from of the C2 vertebral body and can be affected by upper cervical spine instability.
Cervical spine instability can easily irritate the C2 ganglion, as it occupies 76% of the foramen between the arch of C1 and the lamina of C2, or it can irritate the C2 nerve itself when the C2 nerve space is narrowed. By compressing the C2 nerve, cervical spine instability can cause trigeminal neuralgia and migraine headaches. Stimulation of any of the upper cervical nerves (C1-C3) can also give headaches. Periorbital headache pain often comes from irritation of the C1 nerve root. A different kind of occipital headache can also be caused by the trigeminal nerve, C1, and C2 nerves because they each innervate part of the posterior dura, along with the superior cervical ganglion, hypoglossal nerve, and recurrent branches of the vagus nerve as they follow the posterior meningeal artery to provide innervation to the posterior cranial fossa dura mater. Stimulation of the greater occipital nerve is felt in the dura. It is these upper cervical nerve-cranial nerve connections that account for many types of headaches when cervical instability is present.
Ross Hauser, MD. Cause of occipital neuralgia and migraines seen on DMX and resolved with Prolotherapy
In this video, Ross Hauser, MD offers a brief introduction to causes and diagnosis of occipital neuralgia and migraines and treated with the aid of DMX (Digital Motion X-Ray and simple dextrose Prolotherapy cervical spine injections.
While there are absolutely times when surgical intervention is needed, as when there is a space occupying lesion such as a tumor or vascular bundle compressing a nerve, surgery should be reserved if possible as a last result. Doctors do see the surgical failures and sometimes the surgery just makes things worse. To avoid surgery for craniofacial neuralgias it is recommended a person consider this question: Is the neck a potential cause of the pain? Is the underlying true diagnosis missing: upper cervical or even temporomandibular joint instability? If it is, then treatment of this missing diagnosis should be done with Prolotherapy.
We hope you found this article informative and it helped answer many of the questions you may have surrounding Cranial Neuralgias in your complicated neck pain case. Just like you, we want to make sure you are a good fit for our clinic prior to accepting your case. While our mission is to help as many people with chronic pain as we can, sadly, we cannot accept all cases. We have a multi-step process so our team can really get to know you and your case to ensure that it sounds like you are a good fit for the unique testing and treatments that we offer here.
- Vagus nerve compression in the neck: Symptoms and treatments
- Neurologic-like symptoms and conditions of Cervical Spine Instability
- Symptoms of Dysautonomias – Cervical Sympathetic Syndromes
- Neurologic, digestive, cardiac, and bladder disorders: Some of the symptoms of Autonomic nervous system dysfunction and treatment options.
- Symptoms and conditions of cervical spine compression causing internal jugular vein stenosis
- Symptoms and conditions of Craniocervical and Cervical Instability
- Upper cervical instability and Atlantoaxial instability – Compression of the brainstem
- Symptoms and treatments of spinal curvature problems
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