The pterygopalatine ganglion (aka Meckel's ganglion, nasal ganglion, or sphenopalatine ganglion) is a

parasympathetic ganglion Parasympathetic ganglia are the autonomic ganglia of the parasympathetic nervous system. Most are small terminal ganglia or intramural ganglia, so named because they lie near or within (respectively) the organs they innervate. The exceptions are t ...

found in the

pterygopalatine fossa In human anatomy, the pterygopalatine fossa (sphenopalatine fossa) is a fossa in the skull. A human skull contains two pterygopalatine fossae—one on the left side, and another on the right side. Each fossa is a cone-shaped paired depression deep ...

. It is largely innervated by the

greater petrosal nerve The greater petrosal nerve (or greater superficial petrosal nerve) is a nerve in the skull that branches from the facial nerve; it forms part of a chain of nerves that innervate the lacrimal gland. The preganglionic parasympathetic axons of this ne ...

(a branch of the facial nerve); and its postsinaptic axons project to the lacrimal glands and nasal mucosa. The flow of blood to the

nasal mucosa The nasal mucosa lines the nasal cavity. It is part of the respiratory mucosa, the mucous membrane lining the respiratory tract. The nasal mucosa is intimately adherent to the periosteum or perichondrium of the nasal conchae. It is continuous wit ...

, in particular the venous plexus of the conchae, is regulated by the pterygopalatine ganglion and heats or cools the air in the

nose A nose is a protuberance in vertebrates that houses the nostrils, or nares, which receive and expel air for respiration alongside the mouth. Behind the nose are the olfactory mucosa and the sinuses. Behind the nasal cavity, air next passes th ...

. It is one of four parasympathetic ganglia of the head and neck, the others being the

submandibular ganglion The submandibular ganglion (or submaxillary ganglion in older texts) is part of the human autonomic nervous system. It is one of four parasympathetic ganglia of the head and neck. (The others are the otic ganglion, pterygopalatine ganglion, and cil ...

otic ganglion The otic ganglion is a small parasympathetic ganglion located immediately below the foramen ovale in the infratemporal fossa and on the medial surface of the mandibular nerve. It is functionally associated with the glossopharyngeal nerve and in ...

, and

ciliary ganglion The ciliary ganglion is a bundle of nerve parasympathetic ganglion located just behind the eye in the posterior orbit. It is 1–2 mm in diameter and in humans contains approximately 2,500 neurons. The ganglion contains postganglionic parasympath ...

Structure

The pterygopalatine ganglion (of Meckel), the largest of the parasympathetic ganglia associated with the branches of the

maxillary nerve In neuroanatomy, the maxillary nerve (V) is one of the three branches or divisions of the trigeminal nerve, the fifth (CN V) cranial nerve. It comprises the principal functions of sensation from the maxilla, nasal cavity, sinuses, the palate a ...

, is deeply placed in the

, close to the

sphenopalatine foramen The sphenopalatine foramen is a foramen in the skull that connects the nasal cavity with the pterygopalatine fossa. Structure The processes of the superior border of the palatine bone are separated by the ''sphenopalatine notch'', which is convert ...

. It is triangular or heart-shaped, of a reddish-gray color, and is situated just below the maxillary nerve as it crosses the fossa. The pterygopalatine ganglion supplies the

lacrimal gland The lacrimal glands are paired exocrine glands, one for each eye, found in most terrestrial vertebrates and some marine mammals, that secrete the aqueous layer of the tear film. In humans, they are situated in the upper lateral region of each or ...

paranasal sinuses Paranasal sinuses are a group of four paired air-filled spaces that surround the nasal cavity. The maxillary sinuses are located under the eyes; the frontal sinuses are above the eyes; the ethmoidal sinuses are between the eyes and the sphenoid ...

, glands of the mucosa of the

nasal cavity The nasal cavity is a large, air-filled space above and behind the nose in the middle of the face. The nasal septum divides the cavity into two cavities, also known as fossae. Each cavity is the continuation of one of the two nostrils. The nasal c ...

and

pharynx The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...

, the

gingiva The gums or gingiva (plural: ''gingivae'') consist of the mucosal tissue that lies over the mandible and maxilla inside the mouth. Gum health and disease can have an effect on general health. Structure The gums are part of the soft tissue lini ...

, and the mucous membrane and

gland In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure De ...

s of the

hard palate The hard palate is a thin horizontal bony plate made up of two bones of the facial skeleton, located in the roof of the mouth. The bones are the palatine process of the maxilla and the horizontal plate of palatine bone. The hard palate spans ...

. It communicates anteriorly with the

nasopalatine nerve The nasopalatine nerve (long sphenopalatine nerve) is a nerve of the head. It is a branch of the pterygopalatine ganglion, a continuation from the maxillary nerve (V2). It supplies parts of the palate and nasal septum. Structure The nasopalati ...

Roots

It receives a sensory, a parasympathetic, and a sympathetic root.

Sensory root

Its sensory root is derived from two

sphenopalatine Sphenopalatine may refer to: * sphenopalatine artery, an artery of the head, commonly known as the artery of epistaxis * sphenopalatine ganglion (or "pterygopalatine ganglion") * sphenopalatine nerves * sphenopalatine foramen The sphenopalatine for ...

branches of the

; their fibers, for the most part, pass directly into the

palatine nerves The palatine nerves (descending branches) are distributed to the roof of the mouth, soft palate, tonsil, and lining membrane of the nasal cavity. Most of their fibers are derived from the sphenopalatine branches of the maxillary nerve. In older t ...

; a few, however, enter the ganglion, constituting its sensory root.

Parasympathetic root

Its parasympathetic root is derived from the

nervus intermedius The intermediate nerve, nervus intermedius, nerve of Wrisberg or Glossopalatine nerve, is the part of the facial nerve (cranial nerve VII) located between the motor component of the facial nerve and the vestibulocochlear nerve (cranial nerve VIII) ...

(a part of the

facial nerve The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of tas ...

) through the

. In the pterygopalatine ganglion, the preganglionic parasympathetic fibers from the greater petrosal branch of the facial nerve synapse with neurons whose postganglionic axons, vasodilator, and secretory fibers are distributed with the deep branches of the

trigeminal nerve In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and chewin ...

to the mucous membrane of the

soft palate The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. ...

tonsils The tonsils are a set of lymphoid organs facing into the aerodigestive tract, which is known as Waldeyer's tonsillar ring and consists of the adenoid tonsil, two tubal tonsils, two palatine tonsils, and the lingual tonsils. These organs play an ...

uvula The palatine uvula, usually referred to as simply the uvula, is a conic projection from the back edge of the middle of the soft palate, composed of connective tissue containing a number of racemose glands, and some muscular fibers. It also conta ...

, roof of the mouth, upper lip and gums, and upper part of the

. It also sends postganglionic parasympathetic fibers to the

lacrimal nerve The lacrimal nerve is the smallest branch of the ophthalmic nerve (V1), itself a branch of the trigeminal nerve (CN V). The other branches of the ophthalmic nerve are the frontal nerve and nasociliary nerve. Structure The lacrimal nerve branche ...

(a branch of the

ophthalmic nerve The ophthalmic nerve (V1) is a sensory nerve of the face. It is one of three divisions of the trigeminal nerve (CN V). It has three branches that provide sensory innervation to the eye, the skin of the upper face, and the skin of the anterior sca ...

, also part of the trigeminal nerve) via the

zygomatic nerve The zygomatic nerve is a branch of the maxillary nerve, itself a branch of the trigeminal nerve (CN V). It travels through the orbit and divides into the zygomaticotemporal and the zygomaticofacial nerve. It provides sensory supply to skin over ...

, a branch of the

(from the trigeminal nerve), which then arrives at the lacrimal gland. The

nasal glands The nasal glands are the seromucous glands in the respiratory The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and plan ...

are innervated with secretomotor fibers from the nasal branches. Likewise, the

palatine glands The palatine glands form a continuous layer on the posterior surface of the mucous membrane of the soft palate and around the uvula The palatine uvula, usually referred to as simply the uvula, is a conic projection from the back edge of the midd ...

are innervated by the

nasopalatine The nasopalatine nerve (long sphenopalatine nerve) is a nerve of the head. It is a branch of the pterygopalatine ganglion, a continuation from the maxillary nerve (V2). It supplies parts of the palate and nasal septum. Structure The nasopalatin ...

greater palatine nerve The greater palatine nerve is a branch of the pterygopalatine ganglion. This nerve is also referred to as the anterior palatine nerve, due to its location anterior to the lesser palatine nerve. It carries both general sensory fibres from the maxi ...

and lesser palatine nerves. The

pharyngeal nerve The pharyngeal nerve is a small branch of the maxillary nerve, arising from the posterior part of the pterygopalatine ganglion. It passes through the palatovaginal canal with the pharyngeal branch of the maxillary artery, and is distributed to th ...

innervates pharyngeal glands. These are all branches of

Sympathetic root

The ganglion also consists of sympathetic efferent (postganglionic) fibers from the

superior cervical ganglion The superior cervical ganglion (SCG) is part of the autonomic nervous system (ANS); more specifically, it is part of the sympathetic nervous system, a division of the ANS most commonly associated with the fight or flight response. The ANS is comp ...

. These fibers, from the superior cervical ganglion, travel through the carotid plexus, and then through the

deep petrosal nerve The deep petrosal nerve is a branch of the internal carotid plexus which runs through the carotid canal lateral to the internal carotid artery. It enters the cartilaginous substance which fills the foramen lacerum, and joins with the greater petros ...

. The deep petrosal nerve (carrying postganglionic sympathetics) joins with the

(carrying preganglionic parasympathetics) to form the

nerve of the pterygoid canal The nerve of the pterygoid canal (Vidian nerve) is formed by the junction of the greater petrosal nerve and deep petrosal nerve, which passes from the foramen lacerum to the pterygopalatine fossa through the pterygoid canal. Structure The nerve ...

, which passes through the pterygoid canal before entering the ganglion. The stellate ganglion is at the bottom of the cervical sympathetic chain. Fibers from the stellate ganglion pass up the chain to the superior cervical sympathetic ganglion and into and through the sphenopalatine ganglion.

Branches

* Orbital branches *

Nasopalatine nerve The nasopalatine nerve (long sphenopalatine nerve) is a nerve of the head. It is a branch of the pterygopalatine ganglion, a continuation from the maxillary nerve (V2). It supplies parts of the palate and nasal septum. Structure The nasopalati ...

Greater palatine nerve The greater palatine nerve is a branch of the pterygopalatine ganglion. This nerve is also referred to as the anterior palatine nerve, due to its location anterior to the lesser palatine nerve. It carries both general sensory fibres from the maxi ...

Lesser palatine nerve The lesser palatine nerves (posterior palatine nerve) are branches of the maxillary nerve (CN V2). They descends through the greater palatine canal alongside the greater palatine nerve, and emerge (separately) through the lesser palatine foramen to ...

* Posterior superior lateral nasal branches * Pharyngeal branch of maxillary nerve

Blockade and neuromodulation of the pterygopalatine (sphenopalatine) ganglion

Blockade of the ganglion with local anesthetic, clinically referred to as a ‘sphenopalatine ganglion block’ may be performed transcutaneously with a small needle, or topically via the nose with local anesthetic soaked swabs. The topical sphenopalatine ganglion block is used fo
treatment of persistent migraines and cluster headaches
demonstrating relief within 10–20 minutes. Sphenopalatine ganglion block has been used to treat

post-dural-puncture headache Post-dural-puncture headache (PDPH) is a complication of puncture of the dura mater (one of the membranes around the brain and spinal cord). The headache is severe and described as "searing and spreading like hot metal", involving the back and fro ...

, though a 2020 trial comparing local anaesthetic sphenopalatine ganglion block to sham injection with saline failed to show difference in pain scores for those receiving local anaesthetic vs placebo, suggesting any efficacy is unrelated to local anaesthetic blockade. Self-administration of sphenopalatine ganglion blocks with cotton-tipped catheters and continual capillary feed is the most cost-effective method of treatment and has the benefit of allowing patients to avoid visits to physicians and emergency rooms. After initial visit self-administered sphenopalatine ganglion blocks are less than $1.00 per application. Frequent repeated administration of sphenopalatine ganglion blocks seems to increase effectiveness initially, after which decreased frequency is required. Self-administered sphenopalatine ganglion blocks can be used to treat acute pain symptoms, and prophylactically to reduce the onset of painful conditions and anxiety.

Self-administration of sphenopalatine ganglion blocks

Self-administered sphenopalatine ganglion blocks are extremely helpful for treatment of migraines, chronic daily headaches, anxiety and temporomandibular joint disorders

They are also effective in about of cases of essential hypertensio

The sphenopalatine ganglion block has been called "The Miracle Block" after publication of Albert Bengamin Gerber's book ''Miracles on Park Avenue'', the story of octogenerian otorhinolargyngologist Dr. Milton Reder, whose entire medical practice was based on that procedure. There are multiple new devices utilized for neuromodulation of the sphenopalatine ganglion. There is one non-invasive device, a myomonitor, an ultra low frequency transcutaneous electrical nerve stimulation that has been utilized safely for more than 50 years by neuromuscular dentists in the diagnosis and treatment of temporomandibular joint disorders and orofacial pain conditions. Spenopalatine ganglion neuromodulation (possibly via the vagal nerve) is a secondary effect making it extremely effective for TM

Additional images

File:Gray788.png, Plan of the facial and intermediate nerves and their communication with other nerves. File:Gray838.png, The right sympathetic chain and its connections with the thoracic, abdominal, and pelvic plexuses. File:Gray839.png, Diagram of efferent sympathetic nervous system. File:Gray841.png, Sympathetic connections of the sphenopalatine and superior cervical ganglia. File:Gray844.png, Diagram of the cervical sympathetic. File:Maxillary example system.svg, An illustration of the path of the Maxillary nerve.

References

External links

* * (, ) {{Authority control Parasympathetic ganglia Autonomic ganglia of the head and neck Maxillary nerve Facial nerve