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Vulva

The vulva (plurals: vulvas or vulvae), also known as the pudendum, (plural: pudenda) is the collective term given to the female external genitalia. The vulva consists of the: mons pubis labia majora labia minora clitoris bulbs of the vestibule vestibule of the vulva vaginal opening hyme...

Bulbourethral glands

The bulbourethral glands, a.k.a. Cowper glands, are paired small pea-sized glands of the male reproductive tract, homologous to the female Bartholin glands. Gross anatomy The bulbourethral glands are located in the deep perineal pouch posterolateral to the membranous portion of the male urethr...

Lesser sciatic foramen contents (mnemonic)

A mnemonic to remember the structures passing through the lesser sciatic foramen is: PINTO Mnemonic P: pudendal nerve I: internal pudendal artery and vein N: nerve to obturator internus TO: tendon of obturator internus

Infrapiriform foramen (mnemonic)

A mnemonic to remember the structures passing below the piriformis muscle in the greater sciatic foramen is: PIN PINS or SNIP NIP Mnemonic P: posterior cutaneous nerve of thigh I: inferior gluteal artery, vein and nerve N: nerve to quadratus femoris P: pudendal nerve I: internal pudendal ...

Perineal membrane

The perineal membrane is a thin triangular horizontal layer of dense tough fascia in the perineum which divides the urogenital triangle into superficial (inferior) and deep (superior) perineal pouches. It attaches to the inferior margins of the ischiopubic rami, enclosing the anterior portion o...

Endometrium

The endometrium refers to the inner lining of the uterine lumen, composed of endometrial glands surrounded by loose highly cellular connective tissue. Gross anatomy Layers In women of reproductive age, the endometrium is composed of two layers: stratum basale (basal layer): describes the de...

Celiacomesenteric trunk

The celiacomesenteric trunk (CMT) represents an uncommon vascular anatomical variant where both the celiac trunk and the superior mesenteric artery (SMA) have a common origin from the abdominal aorta as a single trunk. Its frequency has been reported to occur in about 1.5% of the population 1,2....

Transverse pancreatic artery

The transverse pancreatic artery, also known as the inferior pancreatic artery, is a branch of the splenic artery that supplies the pancreatic tail and body. It arises from the proximal splenic artery and descends a short distance to run to the left along the posterior margin of the pancreas ne...

Dorsal pancreatic artery

The dorsal pancreatic artery is a branch of the splenic artery that supplies the pancreas. It arises from the proximal splenic artery and descends a short distance to run along the posterior margin of the pancreas where it divides in to left and right branches. the right branches pass either an...

Greater pancreatic artery

The greater pancreatic artery, also known as the pancreatica magna artery, is a branch of the splenic artery that supplies the pancreatic tail and body. It arises approximately two thirds the way along the splenic artery and descends a short distance to run to the left along the posterior margi...

AICA-PICA dominance

AICA-PICA dominance refers to the principle that the cerebellar vascular territory supplied by the anterior inferior cerebellar artery and posterior inferior cerebellar artery have a reciprocal arrangement. That is the size of the AICA and the subsequent territory it supplies is inversely propor...

Inferior hypophyseal artery

The inferior hypophyseal artery is a branch from the meningohypophyseal trunk, a branch of the C4 segment of the internal carotid artery. It is usually single on each side and divides into superior and inferior branches, anastomoses with its counterparts from the opposite, contributing to the in...

Left ventricular false tendon

Left ventricular false tendons, also known as left ventricular muscular bands, are fibromuscular structures that arise from the inner trabeculated myocardial layer of the left ventricle. They may have different lengths and thicknesses. Epidemiology The incidence of false tendons ranges from 18...

Common femoral vein

The common femoral vein (CFV) forms from the confluence of the femoral vein and the deep femoral vein, and continues as the external iliac vein at the inguinal ligament. It accompanies the common femoral artery. Terminology "Common femoral vein" is not listed in Terminologia Anatomica, however...

Killian dehiscence

The Killian dehiscence is a triangular-shaped area of weakness in the muscular wall of the pharynx, between the transverse and oblique bundles of the inferior pharyngeal constrictor 1. It is the most common site of pharyngeal diverticula 5. Gross anatomy It is located in the posterior wall of ...

Rostral sulcus

The rostral sulcus is located medially in the frontal lobe. It is the sulcus which divides the gyrus rectus (or straight gyrus) inferiorly from the inferior portion of the rostral gyrus superiorly1.

Prepatellar bursa

The prepatellar bursa is one of the knee bursae. It is situated anterior to the patella, in the subcutaneous tissue. It is often trilaminar or bilaminar 2. It may communicate with the superficial infrapatellar bursa, the deep infrapatellar bursa, and in some cases the articular space 1. Related...

Pneumocele

Pneumocele refers to focal or diffuse enlargement of an aerated paranasal sinus with thinning of its bony walls. The latter allows differentiation from pneumosinus dilatans in which the walls of the involved paranasal sinus remain intact.

Laryngeal vestibule

The laryngeal vestibule is the part of the laryngeal cavity lying between the laryngeal inlet and vocal folds. Gross anatomy It is found within the supraglottis. It has a wedge-shaped cross-section, its base lying anteriorly, with its apex tapering posteriorly. Relations anterior: tubercle ...

Vestibule (disambiguation)

A vestibule is an anatomical term and refers to a small cavity at the proximal end of a tube. It may refer to: vestibule (aorta) vestibule (ear) vestibule (larynx) vestibule (mouth) vestibule (nose) vestibule (esophagus) vestibule (vulva) History and etymology Vestibule derives ultimate...

Accessory phrenic nerve

The accessory phrenic nerve is an anatomical variant seen in a little over one third of patients (36%). It most commonly arises from the ansa cervicalis, or slightly less commonly, the subclavian nerve. It is unknown as to how much the accessory phrenic nerve contributes to diaphragmatic functio...

Deep cerebral veins

The deep cerebral veins drain the deep white matter and grey matter that surround the basal cisterns and ventricular system. The deep veins are responsible for the outflow of approximately the inner 80% of the hemisphere. They provide useful landmarks for skull base and intraventricular surgery ...

Eyelid

The eyelids cover the eyes, with an upper and lower eyelid on each side, and are covered in front with loose skin and behind with adherent conjunctiva. The lower lids possess very little mobility; lids are closed gently by levator palpebrae superioris muscle fibers and forcefully by the orbicula...

Tarsal plate

The tarsal plates of the eye are formed by dense fibrous tissue representing thickened extensions of the orbital septum, molded to the curvature of the eyeball. Each eye has a superior tarsal plate and an inferior tarsal plate. The plates anchor the roots of the eyelashes and contain tarsal (M...

Conjunctiva

The conjunctiva (plural: conjunctivas or conjunctivae) is a transparent membrane is attached at the margins of the cornea. It is loosely attached to the sclera and thence reflected over the inner surface of the eyelids. It is firmly attached to the tarsal plates and blends with the skin at the m...

Tunica (disambiguation)

Tunica is a word used in anatomy to refer to a type of covering. tunica adventitia (also known as tunica externa) tunica albuginea tunica albuginea (clitoris) tunica albuginea (ovary) tunica albuginea (penis) tunica albuginea (testis) tunica intima tunica media tunica vaginalis tunica...

Tunica albuginea (testis)

The tunica albuginea (TA) forms the fibrous covering of the testis and is itself covered by the serous layer, the tunica vaginalis. The covering is total, except for at the point of attachment of the epididymis, and a small defect posteriorly where the spermatic cord vessels enter and leave the ...

Tunica vaginalis (testis)

The tunica vaginalis (TV) represents the investing serosal covering of the testis. It forms as the embryological testis descends and passes out through the superficial inguinal ring carrying its abdominal peritoneal covering with it. The tunica vaginalis is said to consist of two layers, the pa...

Sural nerve

The sural nerve ( in Latin Sura means Calf) is a sensory nerve of the lower limb formed by the union of sural branch of the tibial nerve and the communicating sural branch of the common fibular nerve supplying sensation to the lower lateral aspect of the calf and foot. Gross anatomy It travel...

Stapediovestibular joint

The stapediovestibular joint is the fully-functional articulation between the stapes and the oval window. It has a key role in the transmission of sound vibrations in the middle ear to the fluid in the vestibule, and thence in the cochlea 2. Gross anatomy The annular ligament of the stapes, a...

Interphalangeal joint of the foot

The interphalangeal joints of the foot are the articulations between adjacent phalanges 1. Each foot has nine interphalangeal joints. The hallux has one interphalangeal joint whilst the lesser digits each have a proximal and a distal interphalangeal joint. Gross anatomy The joint is formed by ...

Oval window

The oval window (or fenestra vestibuli) is a kidney-shaped aperture in the medial wall of the mesotympanum of the middle ear, providing communication with the vestibule of the inner ear. The footplate of the stapes is attached to its rim by the annular ligament 1. The variability of the size o...

Prostatic venous plexus

The prostatic venous plexus (also known as Santorini's plexus) is a network of veins around the anterolateral aspect of the prostate and anterior to the bladder. Tributaries include: deep dorsal vein of the penis anterior vesical rami prostatic rami The receipt of blood from the vesical and ...

Left perihepatic space

The left perihepatic space (also known as the left subhepatic space) is a potential space located between the stomach and the visceral surface of left lobe of the liver. Gross anatomy The left perihepatic space can be further subdivided into anterior and posterior spaces. It is a subcompartmen...

Right supramesocolic space

The right supramesocolic space is an arbitrary subdivision of the supramesocolic space, which lies between the diaphragm and the transverse colon. Gross anatomy The right supramesocolic space is separated from the left supramesocolic space by the falciform ligament, and can be divided into thr...

Uncinate process of the cervical spine

The uncinate process of the cervical spine is a hook-shaped process found bilaterally on the superolateral margin of the cervical vertebral bodies of C3-C7. The uncinate processes are more anteriorly positioned in the upper cervical spine and more posteriorly located in the lower cervical spine...

Thoracoepigastric vein

The thoracoepigastric vein provides a communication between the superficial epigastric vein and the lateral thoracic vein as it ascends superficially on the anterolateral chest and abdominal wall. It, therefore, drains into both the superior vena cava (SVC) via the axillary vein and the inferior...

Subparietal sulcus

The subparietal sulcus is a sulcus on the medial surface of the parietal lobe that separates the precuneus from the posterior aspect of the cingulate gyrus. It is considered a posterior continuation of the cingulate sulcus even if these sulci are most commonly discontinuous.

Superior occipital sulcus

The superior occipital sulcus is a sulcus of the occipital lobe that separates the superior from the middle occipital gyri. It is usually seen as a posterior continuation of the intraparietal sulcus.

Septal nuclei

The septal nuclei are an area of the brain adjacent to the septum pellucidum, anterior to the lamina terminalis and below the rostrum of the corpus callosum. It consists of a subset of four nuclei involved in emotional functioning: dorsal, ventral medial and caudal.

Postcentral sulcus

The postcentral sulcus is a sulcus of the parietal lobe that separates the postcentral gyrus from the remainder of the parietal lobe, thus dividing the primary somatosensory cortex from the secondary somatosensory cortex. It runs parallel and posterior to the central sulcus.

Lateral occipital sulcus

The lateral occipital sulcus is a sulcus of the lateral surface of the occipital lobe that runs horizontally and separates the superior from the inferior occipital gyri.

Primary auditory cortex

The primary auditory cortex (Brodmann area 41, 42) is the part of the temporal lobe that is responsible for the conscious perception of sound. It is located in Heschl's gyrus. It receives inputs from the medial geniculate nucleus.

Medial geniculate body

The medial geniculate body, also known as the medial geniculate nucleus, is one of the thalamic nuclei. It acts as the principal relay nucleus for the auditory system between the inferior colliculus and auditory cortex. Together with the lateral geniculate body, it forms the metathalamus.

Lateral geniculate body

The lateral geniculate body, also known as the lateral geniculate nucleus, is one of the thalamic nuclei. It acts as the principal relay nucleus for the visual system and, as such, it is conveniently located at the termination of the optic tract. Together with the medial geniculate body, it for...

Metathalamus

The metathalamus is a region of the thalamencephalon formed by the medial and lateral geniculate bodies bilaterally. It serves as an important relay nucleus in both the auditory and visual pathways.

Thalamencephalon

The thalamencephalon is an anatomic region that includes the thalamus, metathalamus and epithalamus. It is one of the components that form the diencephalon.

Superior salivary nucleus

The superior salivatory (or salivary) nucleus of the facial nerve is a visceromotor parasympathetic cranial nerve nucleus located in the pontine tegmentum. Gross anatomy The superior salivatory nucleus is located just cranial to the inferior salivatory nucleus within the dorsal aspect of the p...

Nucleus of tractus solitarius

The nucleus of tractus solitarius, also known as the nucleus of the solitary tract or simply the solitary nucleus, is a purely sensory nucleus located in the dorsolateral medulla oblongata and lower pons. It receives many sensory inputs including taste information and sensory information from th...

Spinal canal

The spinal canal, also known as the vertebral canal, is the cavity within the vertebral column that contains the thecal sac and spinal cord. The canal consists of a series of vertebral foramina (the holes at the center of the vertebra) linked with discoligamentous structures. Gross anatomy The...

Planum temporale

The planum temporale is a part of the temporal lobe. Gross anatomy It is located at the upper and posterior aspect of the temporal lobe. It is bordered: anteriorly by Heschl's gyrus posteriorly and laterally by the Sylvian fissure It is usually larger on the left than on the right; this mi...

Recessus terminalis

Recessus terminalis is the name given to a blind-ending ethmoid infundibulum. It is an anatomical variant that occurs when the uncinate process inserts more laterally than usual onto the lamina papyracea. Practical points sinonasal disease extending into the recess terminalis may displace the ...

Frontal ostium

The frontal ostium is an opening of the frontal sinus below the frontal infundibulum that drains into the frontal recess. Together with the frontal infundibulum and recess, it forms the frontal sinus outflow tract.

Frontal sinus outflow tract

The frontal sinus outflow tract, also known as the frontal sinus drainage pathway, are the structures through which mucus from the frontal sinus flow normally. Terminology Depending on the references, the term is used variably, including synonymously with frontal recess a combination of the ...

Frontal infundibulum

The frontal infundibulum is a term that refers to the funnel-shaped inferior narrowing of the frontal sinus. Together with the frontal ostium and frontal recess, it forms the frontal sinus outflow tract.

Frontal bullar cells

The frontal bullar cells are a subset of variably present frontal recess cells located above the ethmoid bulla. Terminology They are nearly identical to suprabullar cells. The distinguishing features with the latter are that the frontal bullar cells are located above the frontal ostium and ext...

Spinal pia mater

The spinal pia mater (or pia mater spinalis) is the innermost layer of the spinal meninges. In congruence to the cranial pia being closely related to the surface of the brain, the spinal pia is closely related to the surface of the spinal cord. Gross anatomy The spinal pia mater is continuou...

Lateral lamella

The lateral lamella (also known as the lamina lateralis) is the name given to the lateral boundary of the cribriform plate of the ethmoid bone. It runs vertically and joins the fovea ethmoidalis inferomedially. It is the thinnest part of the cribriform plate. Practical points The lateral lamel...

Supreme nasal concha

The supreme nasal concha or turbinate is one of the conchae in the nose and is a bony projection, arising from the medial surface of the labyrinth of the ethmoid above the superior nasal concha. Its presence is variable and has been reported in up to 52% of subjects 1. The air passage between t...

Supreme meatus

The supreme meatus is an air passage of the lateral nasal cavity located between the supreme nasal concha and lateral nasal wall. The ostium of a posterior ethmoidal air cell may be seen in the supreme meatus. Terminology The plural of meatus is meatus (Latin noun of the fourth declension) or ...

Superior meatus

The superior meatus is an air passage of the lateral nasal cavity located between the superior nasal concha and lateral nasal wall. The posterior ethmoid air cells and sphenoid sinuses drain into the superior meatus. See also nasal meatus

Inferior meatus

The inferior meatus (plural: meatus) is an air passage of the lateral nasal cavity located between the inferior nasal concha and lateral nasal wall. The nasolacrimal duct drains into the inferior meatus, and Woodruff plexus is located posteriorly.

Middle meatus

The middle meatus is an air passage of the lateral nasal cavity located between the middle nasal concha and lateral nasal wall. The anterior ethmoid air cells, maxillary and frontal sinuses all drain into the middle meatus. See also nasal meatus

Uncinate process

The uncinate process of the ethmoid bone is a thin hook-like osseous structure of the wall of the lateral nasal cavity. Gross anatomy Together with the ethmoid bulla, it forms the boundaries of the hiatus semilunaris and ethmoid infundibulum. The course of the free edge of the uncinate proces...

Nasal meatus

The nasal meatuses are distinct air passages of the lateral nasal cavity located inferior to each nasal conchae. Terminology The plural of meatus is meatus (Latin noun of the fourth declension) or meatuses. Meati is incorrect. Gross anatomy There are three main nasal meatuses: superior mea...

Basal lamella

The basal lamella, also known as basal lamella of the middle turbinate, is an osseous lamella that separates the anterior from the posterior ethmoid sinuses 1. Terminology Internal anterior to posterior partitions of the ethmoid sinuses are called basal lamellae. According to a concept propose...

Lamina papyracea

The lamina papyracea, also known as the orbital lamina of the ethmoid bone, is the principal component of the medial wall of the orbit, and also the lateral surface of the ethmoid air cells. Gross anatomy It articulates: superiorly with the orbital plate of the frontal bone inferiorly with t...

Retrobullar recess

The retrobullar recess is a small potential opening (cleft) rather than an actual air cell located superior and posterior to the ethmoid bulla, separating it from the skull base and basal lamella. The ethmoid bulla usually opens posteriorly in the retrobullar recess. Gross anatomy Boundaries ...

Suprabullar cells

The suprabullar cells are a subset of variably present frontal recess cells located above the ethmoid bulla. Terminology They are nearly identical to frontal bullar cells. The distinguishing features with the latter are that the suprabullar cells are located entirely below the frontal ostium a...

Sinus lateralis

Sinus lateralis is a general term used to described a space behind and/or superior to the ethmoid bulla. As it actually refers to both the suprabullar and retrobullar recesses, the use of these more specific terms is preferred.

Suprabullar recess

The suprabullar recess is a potential opening (cleft) between the bulla lamella and skull base located along the posterior margin of the frontal recess with which it may communicate directly. It is present when the bulla lamella is incomplete superiorly. Terminology The term sinus lateralis i...

Torus ethmoidalis

Torus ethmoidalis, also known as torus lateralis, is the term given when there is no air cell in the ethmoid bulla (failure of pneumatization). It is encountered in 8% of subjects.

Ethmoid bulla

The ethmoid bulla, also known as bulla ethmoidalis, is the largest and most consistent air cell of the anterior ethmoid air cells. Gross anatomy It is located posterior to the frontal recess and enclosed laterally by the lamina papyracea. It forms the roof of the middle meatus. It can be clas...

Bulla lamella

The bulla lamella is a structure that, when intact, forms the posterior boundary of the frontal recess. When pneumatized, it forms the ethmoid bulla. Gross anatomy It is frequently incomplete and often does not reach the roof of the ethmoid at the skull base. Under these circumstances, the fro...

Frontal recess

The frontal recess is an opening in the inferior aspect of the frontal sinuses that allows drainage of the sinus. Terminology The frontal recess is also known as the nasofrontal duct. However, since it does not have bony walls of its own, it is more appropriately referred to as a recess rather...

Lateroconal fascia

The lateroconal fascia is the peritoneal thickening which extends anterolaterally from the adjoining merging lateral borders of the anterior and posterior perirenal fasciae. Gross anatomy It increases progressively in length as it ranges distally. It traverses laterally in a transverse plane a...

Detrusor muscle

The detrusor muscle (or detrusor urinae muscle)is the smooth muscle component of the urinary bladder and facilitates contraction of the bladder wall during micturition. Gross anatomy Forms the smooth muscle component of the bladder wall. The urothelial lining overlies it within the bladder cav...

Asymmetry of the lateral ventricles

The lateral ventricles occasionally show small side to side differences in size on CT or MRI of the brain. This asymmetry of the lateral ventricles (ALV) is an anatomic variant in most cases. Epidemiology The prevalence of asymmetry in lateral ventricle size in those without evidence of underl...

Frontal intersinus septal cells

Frontal intersinus septal cells, also known as interfrontal sinus septal cells, are a subtype of medial frontal recess cells. Gross anatomy The frontal intersinus septal cells lie within the intersinus septum between the frontal sinuses. They usually drain in the medial aspect of the frontal r...

Frontal recess cells

Frontal recess cells are anterior ethmoid air cells that pneumatize the frontal recess. Their clinical relevance lies in their potential to obstruct the frontal recess outflow. As such, they should be reported by the radiologist preoperatively, especially in cases of frontal sinusitis. Named fr...

Frontal cells

Frontal cells are anterior ethmoid air cells located along the anterior aspect of the frontal recess. They are a subset of frontal recess cells and are classified into four types according to Kuhn's classification. They are seen on CT in 20-33% of patients 1. See also functional endoscopic si...

Fishtail pancreas

Fishtail pancreas (also known as pancreas bifidum or bifid tail of the pancreas) is a rare anatomical variant of the pancreas produced by a branching anomaly during its development. It is named as such due to the fishtail-like appearance of the pancreas. Epidemiology It is a rare anatomical an...

Circumventricular organs (CNS)

The circumventricular organs are neuroendocrine anatomical structures localized around the ventricles of the brain. They are characterized by a rich vasculature and fenestrated (permeable) capillaries. As such, with the exception of the subcomissural organ, they are also characterized by the abs...

Gastric bubble

The gastric bubble is a radiolucent rounded area generally nestled under the left hemidiaphragm representing gas in the fundus of the stomach. On a lateral radiograph, the gastric bubble is usually located between the abdominal wall and spine. It can be seen on chest or abdominal plain films. I...

Olive

The olive is the ventral oval prominence in the medulla oblongata which contains the inferior olivary nucleus, implicated in motor co-ordination. Gross anatomy The olive is a smooth ovoid prominence just below the pons. It is located in the superior medulla, lateral to the pyramid and ventrola...

Central base of skull

The central base of skull is a region of the skull base centered on the pituitary fossa and includes surrounding structures. Despite no single universally accepted definition of this region, it is frequently used clinically and is conceptually useful particularly when considering tumors of the ...

Sphenoidal ridge

The sphenoidal ridge, or sphenoid ridge, is the sharp curving bony edge at the posterior aspect of the lesser wing of the sphenoid bone. It separates the horizontal floor of the anterior cranial fossa in front from the vertical anterior wall of the middle cranial fossa behind 1. Related patholo...

Habenular commissure

The habenular commissure is a white matter tract connecting the two habenular nuclei and the internal medullary laminae 1. Whilst the exact role of the habenular commissure is unknown, the habenular nuclei play an important role in influencing how the brain responds to a variety of stimuli, incl...

Accessory semimembranosus muscle

The accessory semimembranosus muscle is a rare accessory muscle of the posterior compartment of the thigh. It arises from the distal aspect of the semimembranosus muscle belly and courses through the popliteal fossa between it and the semitendinosus muscle medially and the biceps femoris lateral...

Ear

The ear refers to the entire vestibulocochlear organ and is divided anatomically into: external ear middle ear inner ear

Posterior auricular vein

The posterior auricular vein is tributary of the external jugular vein or retromandibular vein. Gross anatomy Origin and course It arises over the mastoid process of the temporal bone draining the skin behind the ear and courses anteriorly into the parotid gland, draining into the external ju...

Nucleus accumbens

The nucleus accumbens (plural: nuclei accumbentes) (colloquially known as the pleasure center) is a small region in the forebrain involved in the reward pathway and is therefore involved in impulse control disorders. It is considered part of the corpus striatum ventrale (ventral striatum). Summ...

Supraorbital air cells

Supraorbital air cells are an anatomical variant of the paranasal sinuses. They consist of cells originating from the anterior ethmoid air cells extending posteriorly and superiorly over the orbit from the frontal recess. They may mimic septated frontal sinuses as their posterior wall is the sku...

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