Epistaxis (nosebleed) is very common and has a broad differential diagnosis in clinical practice. In clinical practice, anterior epistaxis are mainly located in Kiesselbach's plexus and posterior epistaxis (5% of all epistaxis) in Woodruff's plexus.
Epistaxis is very common, with ...
Ethmocephaly refers to a rare type of midline cranio-facial anomaly that is characterised by the presence of extreme hypotelorism, arrhinia and a midline proboscis.
holoprosencephaly 1-2: particularly alobar holoprosencephaly
The ethmoidal air cells (or less commonly, the ethmoidal sinuses) form one of the four pairs of paranasal sinuses. They are located within the single, midline ethmoid bone. They are present at birth, and they develop rapidly from 0-4-year-old; they further mature from 8-12-year-old during pubert...
The ethmoid bone is a single midline facial bone that separates the nasal cavity from the brain and is located at the roof of the nose and between the two orbits. It is a cubical shape and is relatively lightweight because of its spongy construction. It contributes to the anterior cranial fossa....
The Eustachian tube is the channel through which the tympanic cavity communicates with the nasopharynx. It is approximately 36 mm in length and is directed downward, forward, and medially, forming an angle of about 45 degrees with the sagittal plane and one of 30 to 40 degrees with the horizonta...
Eustachian tube dysfunction (ETD) is considered by many to be the underlying cause of chronic otomastoiditis, although both the exact pathogenesis and role of ETD in chronic middle ear infections is unclear.
ETD is estimated to be present in ~1% of the adult population.
External auditory canal atresia (EACA) is characterised by complete or incomplete bony atresia of the external auditory canal (EAC) and, especially when seen in the setting of an associated syndrome, a dysplastic auricle and an abnormal middle ear cavity.
The incidence is 1 in 10,...
External auditory canal cholesteatomas are an uncommon locations for cholesteatomas, which are usually in the middle ear or petrous apex. When they occur lateral to the tympanic membrane, they are referred to as external auditory canal cholesteatomas.
The external acoustic cana...
Exostosis of the external auditory canal (also known as surfer's ear), is a benign bony overgrowth of the bony external auditory canal brought about by exposure to cold wind and water combined.
broad-based or more focal circumferential bony overgrowth of the osseous exter...
External auditory canal osteoma is a rare focal pedunculated bony overgrowth of the osseous external auditory canal.
solitary pedunculated bony overgrowth of the external auditory canal usually at the bony cartilaginous junction
large lesions may be associate...
The external carotid artery (ECA) is one of the two terminal branches of the common carotid artery. The other terminal branch is the internal carotid (ICA), which is somewhat larger than the ECA.
origin: bifurcation of the common carotid artery
course: under the submandibular gland an...
The external ear comprises the auricle (or pinna), the external auditory meatus, and the tympanum (eardrum). The pinna concentrates and amplifies sound waves and funnels them through the outer acoustic pore into the external auditory meatus, which carries them to the tympanic membrane.
The external jugular vein (EJV) drains the head, face and part of the pectoral region.
Origin and course
The posterior division of the retromandibular vein and posterior auricular vein unite to form the external jugular vein at the angle of the mandible. It courses inferiorly in...
The extraconal orbital compartment or extraconal space is the space within the orbit outside the musculofascial cone. The base of which is anterior and is formed by the orbital septum that surrounds the equator of the globe. The external sides are formed by the bones of the orbit and their perio...
Extraconal orbital lesions include lesions which arise from structures within the extraconal orbital space and those extending from adjacent structures into the orbits.
dermoid cyst: most common lesion in paediatrics
lacrimial gland lesions
Extracranial meningiomas, also known as primary extradural meningiomas or ectopic meningioma, are a rare location-specific type of meningioma that arise outside the dural covering of the brain and spinal cord. They are essentially extracranial tumours, most often occurring in the head and neck, ...
Extramedullary plasmacytoma (EMP) is an uncommon plasma cell tumour that is composed of monoclonal plasma cells arranged in clusters or sheets. The rate of progression to multiple myeloma (MM) varies from 10% to 30%.
EMP occurs most commonly during the fourth through to seventh de...
An extramural air cell is one that is not contained within its named parent bone. So, the infraorbital ethmoidal air cells that lie within the maxilla rather than the ethmoidal bone are an example of extramural air cells.
A mnemonic to remember the order in which extraocular muscles are involved in thyroid-associated orbitopathy (TAO) is:
I: inferior rectus
M: medial rectus
S: superior rectus
L: lateral rectus
There is some debate about this however. Some claim superior rectu...
The extra-ocular muscles are the six muscles that insert onto the eye and hence control eye movements:
superior rectus: elevation
superior oblique: intorsion
medial rectus: adduction
lateral rectus: abduction
inferior oblique: extorsion
inferior rectus: depression
The extrinsic muscles of the tongue are a group of 4 muscles of the tongue. They all arise outside the tongue, which is in comparison to the intrinsic muscles of the tongue which are entirely within the tongue with no external attachments. They act to alter the position of the tongue where as th...
The extrinsic muscles of the tongue can be remembered with the following mnemonic:
Paris St Germain's Hour
Paris St. Germain's Hour
Exudative retinitis (also known as retinal telangiectasis or Coats disease) is a rare congenital disease affecting the eyes and is a cause of leukocoria.
The exact aetiology is unknown and the disease is a non hereditary disorder. It occurs predominantly in young males, with the ...
Eye movements are a complex set of movements of the globe that are performed by the extra-ocular muscles that are grouped by the muscles that perform particular movements:
ocular internal rotators
ocular external rotators
Facial angiofibroma, also known as fibrous papule, is a fairly common skin lesion seen in males and females after puberty.
They represents a focal vascular and collagen growth.
This lesion is usually solitary and located on the nose skin, measuring 1-5 mm.
There is no hereditary p...
The facial artery is one of the branches of the external carotid artery and supplies blood to the structures of the face.
origin: branch of the external carotid artery a little above the level of the lingual artery
course: ascends anteriorly through the cheek with a tortuous route tow...
The facial bones comprise a set of bones that make up the face:
inferior nasal concha
zygoma (zygomatic bone)
Where these bones join each other, sutures occur.
The facial-cavernous anastomoses are the communications of the facial and deep facial veins with the cavernous sinus.
At the medial canthus of the eye there is a communication with the ophthalmic veins, which drain into the cavernous sinus. Blood from the frontal scalp normally f...
Facial clefts comprise of a wide spectrum of pathologies which result from failure of fusion in the facial region during the embryonic - early fetal period. This results is gap in the fetal face. These clefts can affect the lip, philtrum, alveolus and hard and soft palate to varying degrees.
Facial fractures are commonly caused by blunt or penetrating trauma sustained during motor vehicle accidents, assaults, and falls. The facial bones are thin and relatively fragile making them susceptible to injury.
Males are affected more commonly than females and facial fractures...
The facial muscles enable facial expression and serve as sphincters and dilators of the orifices of the face. These muscles differ from those of other regions in the body as there is no fascia deep to the skin of the face; many of the facial muscles insert directly into the skin 1.
The facial nerve is one of the key cranial nerves with a complex and broad range of functions.
Although at first glance it is the motor nerve of facial expression which begins as a trunk and emerges from the parotid gland as five branches (see facial nerve branches mnemonic), it has taste and p...
There are many mnemonics to recall the branches of the facial nerve (superior to inferior) as they exit the anterior border of the parotid gland. Examples include:
Tall Zulus Bear Many Children
Two Zulus Bit My Cat
Two Zebras Bit My Coccyx
Ten Zebras Buggered My Car
To Zanzibar By Motor Car...
Facial palsy refers to the neurological syndrome of facial paralysis. It can result from a broad range of physiological insults to the facial nerve or its central nervous system origins. The most common causes of this is Bell palsy.
While facial palsy refers to the clinical presen...
The facial vein (previously known as the anterior facial vein) is the continuation of the angular vein and joins the anterior branch of the retromandibular vein to form the common facial vein 1-3.
At the level of the lower margin of the orbit, the angular vein becomes the facial ...
Factitious hyperthyroidism or thyrotoxicosis factitia refers to precipitation of thyrotoxicosis due to exogenous ingestion of thyroid hormone (e.g. levothyroxine). It has been rarely associated with myocardial ischaemia 2.
The hypervascularity which is seen wi...
The falciform crescent (or crista falciformis) is a horizontal ridge that divides the internal acoustic meatus into superior and inferior portions.
The facial nerve and superior vestibular nerve (SVN) travel in the superior portion of the IAM with the facial nerve anterior to the SVN ...
The Fallopian (facial) canal refers to a bony canal through which the facial nerve traverses the petrous temporal bone, from the internal acoustic meatus to the stylomastoid foramen.
It is, for those of you fond of trivia, the longest bony canal through which a nerve passes. It is also responsi...
The false vocal cords (vestibular folds, ventricular folds) are paired shelf-like structures located within the supraglottic larynx that divide the vestibule above from the ventricle below.
The vestibular ligaments are the ligamentous component of the false vocal cords and const...
Fatty nodal metaplasia in the neck occurs as a result of chronic inflammation or radiotherapy 3. The normal fatty nodal hilum enlarges, such that the lymph node appears cystic. However, its center is of fatty density. There is no surrounding stranding, and the node otherwise looks normal.
Faulty fetal packing, also known as congenital vault depression, is a congenital concave depression of the skull in a newborn.
Occurs in 1 in 10,000 births 1.
This appearance is due to external compression on the skull from 1,2:
fetal limb or twin
Febrile infection-related epilepsy syndrome (FIRES) is a severe postinfectious neurological disorder that presents with status epilepticus in a previously normal child (or less commonly adult) after a febrile illness.
FIRES has received several names in the literature:
A fetal goitre is an enlargement of the thyroid gland in utero. It can occur with either hyper or hypothyroidism (and in isolated cases of euthyroidism 8).
The mechanism is different depending on whether the underlying cause is hyper or hypothyroidism.
First branchial cleft cysts are a type of branchial cleft anomaly. They are uncommon and represent only ~7% of all branchial cleft cysts.
They are usually diagnosed in middle-aged women 3-4.
Their presentation can in the form of 3:
asymptomatic, e.g. inci...
The fissula ante fenestram (FAF), also known as the cochlear cleft, is a small connective tissue-filled cleft located where the tendon of the tensor tympani muscle turns laterally toward the malleus. It is situated immediately anterior to the oval window, and posterior to the cochleariform proce...
The fistula test is used when examining a patient with recurrent vertigo.
A finger is abruptly applied to the external meatus which causes a pulse of air-transmitted pressure. If nystagmus is induced in association with vertigo, it indicates bony destruction within the inner ear e.g. cholesteat...
Floating teeth is the description given to the appearances on imaging of teeth 'hanging in the wind' as a result of alveolar bone destruction around the root of the teeth.
They are uncommonly encountered, with a wide differential diagnosis - albeit that the underlying c...
The floor of mouth is an oral cavity subsite and is a common location of oral cavity squamous cell carcinoma.
The floor of mouth is a U-shaped space extends (and includes) from the oral cavity mucosa superiorly, and the mylohyoid muscle sling 2,3.
superiorly: oral ...
Focal calvarial thinning can result from a number of causes. They include:
bilateral thinning of the parietal bones (normal variant) most common
mega cisterna magna
peripherally located tumors (e.g. oligodendroglioma)
Follicular thyroid adenoma is a commonly found benign neoplasm of the thyroid consisting of differentiated follicular cells. It can not be differentiated from follicular carcinoma on cytologic, sonographic or clinical features alone 1.
Follicular thyroid adenoma is more commonly f...
Follicular thyroid carcinoma (FTC) is the second most frequent malignancy of the thyroid gland after papillary cancer and accounts for ≈10-20% of all thyroid neoplasms.
It typically occurs in women and in an older age group than papillary (i.e. 40-60 years of age).
The foramen caecum is located in the anterior cranial fossa, anterior to the cribriform plate of the ethmoid bone and posterior to the frontal bone, within the frontoethmoidal suture. It lies at a variable distance from the crista galli.
The foramen caecum is frequently found in infants, uncomm...
Foramen caecum can refer to a number of different anatomical structures:
foramen caecum (tongue)
foramen caecum (anterior cranial fossa)
The foramen lacerum is a triangular opening located in the middle cranial fossa anterior to the petrous apex, which forms its posterior border. Its anterior border is formed by the body of the sphenoid bone at the junction of greater wing and pterygoid process and medial border is formed by the ...
A mnemonic to remember foramen ovale contents is:
O: otic ganglion (inferior)
V: V3 cranial nerve (mandibular division of the trigeminal nerve)
A: accessory meningeal artery
L: lesser petrosal nerve
E: emissary veins
Foramen ovale is an oval shaped opening in the middle cranial fossa located at the posterior base of the greater wing of the sphenoid bone, lateral to the lingula. It transmits the mandibular division of the trigeminal nerve (CN Vc), accessory meningeal artery, emissary veins between the caverno...
The foramen rotundum is located in the middle cranial fossa, inferomedial to the superior orbital fissure at the base of greater wing of the sphenoid bone. Its medial border is formed by lateral wall of sphenoid sinus. It runs downwards and laterally in an oblique path and joins the middle crani...
The foramen tympanicum (also known as foramen of Huschke) is an anatomical variation in the external acoustic canal (EAC), where a bony defect connects the EAC to the temporomandibular joint (TMJ).
Various studies have reported on the occurrence of a foramen tympanicum in the asym...
The foramen Vesalii, also know as the foramen of Vesalius, sphenoidal emissary foramen, foramen venosus or canaliculus sphenoidal, is a tiny variably present foramen in the greater wing of the sphenoid bone, located between the foramen ovale and scaphoid fossa. It transmits a sphenoidal emissary...
Fourth branchial cleft cysts are very rare, and parallel the course of the recurrent laryngeal nerve. They are most commonly on the left side (80%) and usually form a sinus which extends from the apex of the piriform sinus, as do third branchial cleft sinuses, but passes inferiorly rather than s...
The fovea ethmoidalis is a portion of the ethmoid bone and represents its superior portion (part of the ethmoid roof) which is seen as a continuation of the superior orbital roof to the cribriform plate.
A foveola pharyngica recess is one of the variants of the inferior median clival canal, thought to represent a remnant of the notocord. It represents a blind ending recess in the anteroinferior surface (nasopharyngeal) surface of the clivus 1,2.
The frontal bone is a skull bone that contributes to the cranial vault. It contributes to form part of the anterior cranial fossa.
The frontal bone has two portions:
vertical portion (squama): has external/internal surfaces
horizontal portion (orbital): has superior/inferior su...
Frontal bossing is a calvarial radiographic feature where the front of the skull appears protruding anteriorly. It is best appreciated on a sagittal or lateral image.
This feature can be seen in many conditions (in alphabetical order):
The frontal nerve is a largest and main branch of the ophthalmic division of the trigeminal nerve. It divides off the ophthalmic division just before entering the orbit through the superior orbital fissure outside and superolateral to the tendinous ring, where it lies between the lacrimal nerve ...
The frontal sinuses are the paranasal sinuses within the frontal bone. They are lined with mucosa and are most often two in number.
location: anterior frontal bones on either side of the midline behind the brow ridges
blood supply: supratrochlear, supraorbital and anterior ethmoidal a...
The frontoethmoidal suture is a short cranial suture located in the anterior cranial fossa, between the orbital process of frontal and orbital plate of ethmoid bones. It forms part of the medial wall of the orbit.
The anterior and posterior ethmoidal foramina are seen just superior to it, throu...
The frontolacimal suture is the cranial suture between the frontal and lacrimal bones.
The frontomaxillary suture is the site where the nasal process of frontal bone meets the frontal process of the maxilla.
Frontonasal dysplasia is a rare disorder involving the face and often the central nervous system:
median cleft lip
absence of the nasal tip
central nervous system
cranium bifidum occultum
agenesis of the corpus callosum
The frontonasal suture is the cranial suture between the frontal bone and the two nasal bones. This suture meets the internasal suture at the nasion.
The frontozygomatic suture (or zygomaticofrontal suture) is between the frontal process of the zygomatic bone and the zygomatic process of the frontal bone.
Functional endoscopic sinus surgery (FESS) is performed intranasally using a rigid endoscope. Its primary objective is to restore physiological ventilation and mucociliary transport 1.
Sinus imaging is crucial in preoperative planning and is increasingly being used intraoperatively.
Fungal sinusitis is a collective term referring to a number of entities, which can be divided into two groups, depending on the presence of fungal hyphae within or beyond the mucosa 1:
non-invasive: hyphae do not invade mucosa
allergic fungal sinusitis
sinus fungal mycetoma
invasive: hyphae ...
The galea aponeurotica (also called the Galeal or epicranial aponeurosis or the aponeurosis epicranialis) is a tough fibrous sheet of connective tissue that extends over the cranium, forming the middle (third) layer of the scalp.
Garrington sign is thickening of the periodontal ligament/membrane space of involved teeth in the setting of gnathic osteosarcoma. Symmetrical widening of the space can be seen early in the disease process due to infiltration of tumour cells.
The genioglossus muscle is a fan-shaped extrinsic muscles of the tongue which makes up the bulk of the tongue.
origin: superior mental spine of the symphysis menti (posterior surface of midline mandible)
insertion: entire tongue mass and body of the hyoid bone
nerve supply: hypogloss...
The geniohyoid muscle is one of the suprahyoid muscles of the neck that is innervated by the ventral ramus of C1. Geniohyoid draws the hyoid bone up and forward during mastication and assists the opening of the mandible.
origin: inferior mental spine of the mandible also known as the g...
Genioplasty or in more simple terms chin augmentation refers to a surgical procedure performed to improve facial balance and/or rejuvenate the lower facial third - mandible. An osseous genioplasty refers to surgery which is performed by creating an osteotomy and then mobilising an inferior segme...
A geographic skull is a radiographic appearance which is seen in eosinophilic granuloma (EG) and characterised by destructive lytic bone lesions, the edges of which may be bevelled, scalloped or confluent.
The glabella is the smooth midline bony prominence between the supraciliary arches of the frontal bone, representing the most anterior part of the forehead when standing erect and look straight ahead. The metopic suture traverses the glabella, between the two frontal bones. Just below it is the ...
The globes or simply, the eyes are paired spherical sensory organs, located anteriorly on the face within the orbits, which house the visual apparatus.
The globe is suspended by the bulbar sheath in the anterior third of the bony orbit.
Each globe is an approxim...
Globe rupture is an ophthalmologic emergency. A ruptured globe or an open-globe injury must be assessed in any patient who has suffered orbital trauma because open-globe injuries are a major cause of blindness.
In a blunt trauma, ruptures are most common at the insertions of the intraocular mus...
Globus pharyngeus is the subjective feeling of a lump in the throat which can have a variety of causes. In modern practice globus is often evaluated by flexible nasoendoscopy in the first instance since many patients present to otolaryngology services. If no cause is identified or if nasoendosco...
Glomus jugulare paraganglioma is a paraganglioma of the head and neck that is confined to the jugular fossa. While it is a rare tumour, it is the most common of the jugular fossa tumours.
The relative prevalence of glomus jugulare with respect to other head and neck paraganglioma ...
Glomus tympanicum paragangliomas (chemodectomas) are the most common middle ear tumour.
There is a female predominance (M:F = 1:3); presentation is most common when patients are more than 40 years old 1,2.
May be incidental but symptomatic masses produce ...
Glomus vagale tumours are glomus tumours that occur along the path of the vagus nerve (CN X). They are a subset of extra-adrenal neuroendocrine tumours that are derived from the nonchromaffin paraganglion cells.
Typically presents as a painless mass behind the carotid ar...
The glossopharyngeal nerve is the ninth (IX) of the twelve pairs of cranial nerves. It exits the brainstem out from the sides of the upper medulla, just rostral to the vagus nerve and has sensory, motor, and autonomic components.
The sensory ganglion cells lie in the supe...
Glossopharyngeal neuralgia is due to irritation of the glossopharyngeal nerve and presents with repeated episodes of severe pain in the tongue, throat, ear, and tonsils, which can last from a few seconds to a few minutes. It is far less common than trigeminal neuralgia.
Goitre refers to enlargement of the thyroid gland. It can occur from multiple conditions.
The definition of a goitre depends on age and sex; below are the upper limits of normal for thyroid gland volume 1:
adult males: 25 mL
adult females: 18 mL
13-14 years: 8-10 mL
3-4 years: 3 mL
Goldenhar syndrome (also known as oculo-auriculo-vertebral spectrum (OAVS), Goldenhar-Gorlin syndrome or facio-auriculo-vertebral dysplasia) is a complex congenital anomaly characterised by abnormalities of the ears, eyes and vertebrae.
The estimated incidence is at 1 in 3000-500...
Gorlin-Goltz syndrome, also known as the basal cell naevus syndrome, is a rare phakomatosis characterised by multiple odontogenic keratocysts (KOT), multiple basal cell carcinomas (BCC), and other abnormalities.
The condition is thought to occur in ~1 in 60,000 live births while 0...
Gradenigo syndrome consists of the triad of:
abducens nerve palsy, secondary to involvement of the nerve as it passes through Dorello canal
retro-orbital pain, or pain in the cutaneous distribution of the frontal and maxillary divisions of the trigeminal nerve, due to extensi...