A persistent stapedial artery (PSA) is a rare anomaly in

human anatomy Human anatomy (gr. ἀνατομία, "dissection", from ἀνά, "up", and τέμνειν, "cut") is primarily the scientific study of the morphology of the human body. Anatomy is subdivided into gross anatomy and microscopic anatomy. Gross ...

where the stapedial branch of posterior auricular artery, or simply stapedial artery, remains within the

ear In vertebrates, an ear is the organ that enables hearing and (in mammals) body balance using the vestibular system. In humans, the ear is described as having three parts: the outer ear, the middle ear and the inner ear. The outer ear co ...

of a

fetus A fetus or foetus (; : fetuses, foetuses, rarely feti or foeti) is the unborn offspring of a viviparous animal that develops from an embryo. Following the embryonic development, embryonic stage, the fetal stage of development takes place. Pren ...

after the first ten weeks of

pregnancy Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Conception (biology), Conception usually occurs ...

. Whilst not problematic for the majority of people with the anomaly, it can cause difficulties with

hearing Hearing, or auditory perception, is the ability to perceive sounds through an organ, such as an ear, by detecting vibrations as periodic changes in the pressure of a surrounding medium. The academic field concerned with hearing is auditory sci ...

Signs and symptoms

Most cases of PSA cases remain

asymptomatic Asymptomatic (or clinically silent) is an adjective categorising the medical conditions (i.e., injuries or diseases) that patients carry but without experiencing their symptoms, despite an explicit diagnosis (e.g., a positive medical test). P ...

for a person's life; however, symptoms can include

vertigo Vertigo is a condition in which a person has the sensation that they are moving, or that objects around them are moving, when they are not. Often it feels like a spinning or swaying movement. It may be associated with nausea, vomiting, perspira ...

pulsatile tinnitus Tinnitus is a condition when a person hears a ringing sound or a different variety of sound when no corresponding external sound is present and other people cannot hear it. Nearly everyone experiences faint "normal tinnitus" in a completely ...

conductive hearing loss Conductive hearing loss (CHL) is a type of hearing impairment that occurs when sound waves are unable to efficiently travel through the outer ear, tympanic membrane (eardrum), or middle ear structures such as the ossicles. This blockage or dysfun ...

sensorineural hearing loss Sensorineural hearing loss (SNHL) is a type of hearing loss in which the root cause lies in the inner ear, sensory organ (cochlea and associated structures), or the vestibulocochlear nerve (Cranial nerves, cranial nerve VIII). SNHL accounts for a ...

via bone erosion of the otic capsule in rare cases. Hearing loss in

children A child () is a human being between the stages of childbirth, birth and puberty, or between the Development of the human body, developmental period of infancy and puberty. The term may also refer to an unborn human being. In English-speaking ...

can also cause developmental delays.

Cause

During

, the stapedial artery originates as a branch of the hyoid artery in the dorsal branch of the second

aortic arch The aortic arch, arch of the aorta, or transverse aortic arch () is the part of the aorta between the ascending and descending aorta. The arch travels backward, so that it ultimately runs to the left of the trachea. Structure The aorta begins ...

, which is in turn connected to the

internal carotid artery The internal carotid artery is an artery in the neck which supplies the anterior cerebral artery, anterior and middle cerebral artery, middle cerebral circulation. In human anatomy, the internal and external carotid artery, external carotid ari ...

. The stapedial artery after passing through the

stapes The ''stapes'' or stirrup is a bone in the middle ear of humans and other tetrapods which is involved in the conduction of sound vibrations to the inner ear. This bone is connected to the oval window by its annular ligament, which allows the f ...

splits into two vessels, the supraorbital branch and the maxillomandibular branch, the latter of which has a smaller mandibular branch. The former later

anastomose An anastomosis (, : anastomoses) is a connection or opening between two things (especially cavities or passages) that are normally diverging or branching, such as between blood vessels, leaf veins, or streams. Such a connection may be normal (su ...

s with the

ophthalmic artery The ophthalmic artery (OA) is an artery of the head. It is the first branch of the internal carotid artery distal to the cavernous sinus. Branches of the ophthalmic artery supply all the structures in the orbit around the eye, as well as some ...

and becomes the

middle meningeal artery The middle meningeal artery (') is typically the third branch of the maxillary artery#First portion, first portion of the maxillary artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum t ...

, the latter anastomoses with the internal maxillary branch of the

external carotid artery The external carotid artery is the major artery of the head and upper neck. It arises from the common carotid artery. It terminates by splitting into the superficial temporal and maxillary artery within the parotid gland. Structure Origin T ...

, becoming the inferior alveolar artery and

infraorbital artery The infraorbital artery is a small artery in the head that arises from the maxillary artery and passes through the inferior orbital fissure to enter the orbit, then passes forward along the floor of the orbit, finally exiting the orbit through the ...

, respectively.

Diagnosis

Since most cases of PSA do not present with symptoms, it is usually discovered incidentally upon

middle ear The middle ear is the portion of the ear medial to the eardrum, and distal to the oval window of the cochlea (of the inner ear). The mammalian middle ear contains three ossicles (malleus, incus, and stapes), which transfer the vibrations ...

surgery Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...

, or during postmortem

temporal bone The temporal bone is a paired bone situated at the sides and base of the skull, lateral to the temporal lobe of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples where four of the cranial bone ...

dissection Dissection (from Latin ' "to cut to pieces"; also called anatomization) is the dismembering of the body of a deceased animal or plant to study its anatomical structure. Autopsy is used in pathology and forensic medicine to determine the cause of ...

s. The absence of the

foramen spinosum The foramen spinosum is a Foramen, small open hole in the greater wing of the sphenoid bone that gives passage to the middle meningeal artery and vein, and the meningeal branch of the mandibular nerve (sometimes it passes through the Foramen ova ...

is sometimes associated with a PSA, although the

prevalence In epidemiology, prevalence is the proportion of a particular population found to be affected by a medical condition (typically a disease or a risk factor such as smoking or seatbelt use) at a specific time. It is derived by comparing the number o ...

of a missing foramen spinosum is much higher than the prevalence of a PSA. On the other hand, a foramen spinosum may be present if the maxillomandibular artery originates from the stapedial artery. A

differential diagnosis In healthcare, a differential diagnosis (DDx) is a method of analysis that distinguishes a particular disease or condition from others that present with similar clinical features. Differential diagnostic procedures are used by clinicians to di ...

can help eliminate other possible conditions such as glomus tumour of the tympanicum, facial nerve schwannoma, and aberrant

(ICA) based on results of high-resolution computed tomograms,

angiogram Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. Modern angiography is perform ...

s, or magnetic resonance angiograms. An aberrant ICA refers to when

agenesis In medicine, agenesis () refers to the failure of an organ to develop during embryonic growth and development due to the absence of primordial tissue. Many forms of agenesis are referred to by individual names, depending on the organ affected: ...

of the cervical portion of the ICA occurs, causing the inferior tympanic artery to

with the caroticotympanic artery. This causes the internal carotid artery to enter the

through the same canal as the

tympanic nerve The tympanic nerve ( Jacobson's nerve) is a branch of the glossopharyngeal nerve passing through the petrous part of the temporal bone to reach the middle ear. It provides sensory innervation for the middle ear, the Eustachian tube, the parotid ...

, rather than the normal carotid canal. Aberrant internal carotid arteries are often found alongside a PSA, although both anomalies can occur independent of each other.

Treatment

Treatment of PSA usually involves some form of

coagulation Coagulation, also known as clotting, is the process by which blood changes from a liquid to a gel, forming a thrombus, blood clot. It results in hemostasis, the cessation of blood loss from a damaged vessel, followed by repair. The process of co ...

, either laser coagulation or

electrocoagulation Electrocoagulation (EC) is a technique used for wastewater treatment, wash water treatment, industrially processed water, and medical treatment. Electrocoagulation has become a rapidly growing area of wastewater treatment due to its ability to remo ...

Palliative care Palliative care (from Latin root "to cloak") is an interdisciplinary medical care-giving approach aimed at optimizing quality of life and mitigating or reducing suffering among people with serious, complex, and often terminal illnesses. Man ...

such as the installation of

hearing aid A hearing aid is a device designed to improve hearing by making sound audible to a person with hearing loss. Hearing aids are classified as medical devices in most countries, and regulated by the respective regulations. Small audio amplifiers ...

s can help resolve

hearing loss Hearing loss is a partial or total inability to hear. Hearing loss may be present at birth or acquired at any time afterwards. Hearing loss may occur in one or both ears. In children, hearing problems can affect the ability to acquire spo ...

caused by a PSA; conversely, the PSA may prevent the insertion of

cochlear implant A cochlear implant (CI) is a surgically implanted Neuroprosthetics, neuroprosthesis that provides a person who has moderate-to-profound sensorineural hearing loss with sound perception. With the help of therapy, cochlear implants may allow for imp ...

s meant to alleviate the hearing loss.

Ablation Ablation ( – removal) is the removal or destruction of something from an object by vaporization, chipping, erosion, erosive processes, or by other means. Examples of ablative materials are described below, including spacecraft material for as ...

of the PSA is also an option, although this treatment carries the risk of potential

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 ta ...

damage and

haemorrhage Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...

. The central hospital of the

University of Porto The University of Porto (''Universidade do Porto'') is a Portuguese public research university located in Porto, and founded on 22 March 1911. It is the second largest Portuguese university by number of enrolled students, after the University ...

reported in 2016 the first successful implementation of a bone-anchored hearing aid in an 8-year-old patient without complications, successfully resolving their hearing loss. Further successful insertions of cochlear implants to resolve hearing loss have also been reported.

Epidemiology

The

of persistent stapedial arteries is thought to be somewhere between 0.02 and 0.48% of the general population; a study in the '' American Journal of Radiology'' in 2000 stated that only fifty-six cases of PSA had been reported since the first report of PSA was published in 1836 by Austrian anatomist Josef Hyrtl.

Notes

References

{{medical resources , ICD11={{ICD11, LA22.3 , ICD10={{ICD10, Q16.3 Ear Arteries of the head and neck Congenital disorders of eye, ear, face and neck