The paired sublingual glands are major salivary glands in the mouth. They are the smallest, most diffuse, and the only unencapsulated major salivary glands. They provide only 3-5% of the total salivary volume. The gland receives its blood supply from the sublingual and submental arteries. The sublingual artery is a branch of the lingual artery, thus damage to the lingual artery will decrease the blood flow to the sublingual gland.

Patients with a Quinsy or peritonsillar abscess (PTA) typically present with a history of acute pharyngitis accompanied by tonsillitis and worsening unilateral pharyngeal discomfort. Patients also may experience malaise, fatigue, and headaches. They often present with a fever and asymmetric throat fullness. Associated halitosis, odynophagia, dysphagia, and a hot potato–sounding voice occurs.The presentation may range from acute tonsillitis with unilateral pharyngeal asymmetry to dehydration and sepsis. Most patients have severe pain. Examination of the oral cavity reveals marked erythema, asymmetry of the soft palate, tonsillar exudation, and contralateral displacement of the uvula.Indications for considering the diagnosis of a PTA include the following:Unilateral swelling of the peritonsillar areaUnilateral swelling of the soft palate, with anterior displacement of the ipsilateral tonsilNonresolution of acute tonsillitis, with persistent unilateral tonsillar enlargementA PTA ordinarily is unilateral and located at the superior pole of the affected tonsil, in the supratonsillar fossa. At the level of the supratonsillar fold, the mucosa may appear pale and even show a small pimple. Palpation of the soft palate often reveals an area of fluctuance. Flexible nasopharyngoscopy and laryngoscopy are recommended in patients experiencing airway distress. The laryngoscopy is key to ruling out epiglottitis and supraglottitis, as well as vocal cord pathology.

A lumbar puncture, also known as a spinal tap, is a procedure that involves inserting a needle into the lower back’s lumbar region. A needle is inserted into the space between the arachnoid mater and the pia mater, also known as the subarachnoid space, to remove a sample of cerebrospinal fluid.

The middle cerebral artery is a part of the circle of Willis system of anastomosis within the brain, and the most often affected by brain pathology. The primary function of the middle cerebral artery is providing oxygenated blood to related regions of the brain. It achieves this by giving off different branches to supply different brain regions, namely: The cortical branches: which supplies the primary motor and somatosensory cortical areas of some parts of the face, trunk and upper limbs. The small central branches: which supply the basal ganglia and internal capsule via the lenticulostriate vessels. The superior division: which supplies the lateral inferior frontal lobe, including the Broca area which is responsible for production of speech, language comprehension, and writing. The inferior division: which supplies the superior temporal gyrus, including Wernicke’s area which controls speech comprehension and language development.

The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains: Muscles: thyrohyoid, sternothyroid, sternohyoid muscles Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerve The posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle. Contents: Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus

The tip of the shoulder is formed by the acromion of the scapula. This part is moved by the trapezius muscle which is innervated by the accessory nerve. Damage to this nerve therefore will prevent the patient from lifting the tip of the shoulder.

The following structures arise from each branchial pouch: 1st pouch – eustachian tube, middle ear, mastoid, and inner layer of the tympanic membrane2nd pouch – middle ear, palatine tonsils3rd pouch – inferior parathyroid glands, thymus 4th pouch – superior parathyroid glands, ultimobranchial body which forms the parafollicular C-cells of the thyroid gland, musculature and cartilage of larynx (along with the sixth pharyngeal pouch)5th pouch – rudimentary structure6th pouch – along with the fourth pouch, contributes to the formation of the musculature and cartilage of the larynx.

The spinal cord starts at the foramen magnum, where it is continuous with the medulla oblongata, which is the most caudal portion of the brainstem. It then extends inferiorly through the vertebral canal. In adults, it usually ends at the level of the first or second lumbar vertebra.

The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains: Muscles: thyrohyoid, sternothyroid, sternohyoid muscles Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerve The posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle. Contents: Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus

Cough is an important defensive reflex that helps clear secretions and particulates from the airways. A complex reflex arc generates each cough. The cough reflex begins with irritation of the cough receptors present in the epithelium of the trachea, main carina, branching points of large airways, and more distal smaller airways. These receptors are responsive to both mechanical and chemical stimuli. Afferent pathway: Impulses from stimulated receptors are transmitted via sensory nerve fibres of the vagus nerve (mainly) and glossopharyngeal nerve and travel to the medulla diffusely. CN 5 is also thought to contribute to the afferent limb. However, the vagus is the main nerve. Central pathway: The cough centre is located in the upper brain stem and pons Efferent pathway: Impulses from the centre travel via the vagus, phrenic nerve, and spinal motor nerves to the diaphragm, abdominal wall, and muscles.

Branchial cleft cysts are congenital anomalies that usually arise from second cleft/pouch, with remnants of the third and fourth pouch are rare. Children are typically born with these congenital lesions; however, they may not be evident for weeks, months, or possibly years. The lesions present as fistulae, cyst, sinus tracts, or cartilaginous remnants due to incomplete obliteration during embryogenesis.They are often asymptomatic, but can often become tender, enlarged, or inflamed with possible abscess formation during episodes of upper respiratory tract infections. The patient can present with purulent drainage of the sinus to skin or pharynx from spontaneous rupture of branchial cleft cyst abscess. The most concerning symptoms include dysphagia, dyspnoea, and stridor due to cyst compression of the upper airway.The physical examination will differ depending on the location of the branchial cleft cyst:- A primary branchial cleft cyst is typically smooth, non-tender, fluctuant mass found between the external auditory canal and submandibular area. It is usually with the parotid gland and facial nerve. Two types of lesions exist. Type 1 is rare and characterized as duplication of the membranous external auditory canal. Type 2 lesions contain both ectoderm and mesoderm elements including cartilage. The patient usually presents with soft tissue mass or draining sinus located on the angle of the mandible or otorrhea, making an otologic exam critical in these cases.- A secondary branchial cleft cyst is located between the lower anterior border of the sternocleidomastoid and the tonsillar fossa of the pharynx. It can be in proximity to the glossopharyngeal and hypoglossal nerve as well as carotid vessels. Compared to the primary branchial cleft cysts, secondary cysts are tender if secondarily inflamed or infected. If it is associated with a sinus tract, a mucoid or purulent discharge may be present on the skin or into the pharynx.The treatment of a branchial cleft cyst is typically elective excision due to the risk of infection or present infection, further enlargement, or malignancy.- Carotid Body Tumour: Painless oropharyngeal or upper anterior triangle of the neck; pulsatile, compressible with a bruit or thrill, mobile from medial to lateral direction.- Bartonella henselae infection is Isolated, mobile, fluctuant, tender, warm, erythematous, > 2 cm near the site of inoculation.- Thyroglossal duct cyst: In the Midline, adjacent to the hyoid bone; rises with deglutition.

The parotid duct or Stensen duct is a duct and the route that saliva takes from the major salivary gland, the parotid gland into the mouth. The parotid duct is formed when several interlobular ducts—the largest ducts inside the parotid gland join. It emerges from the gland and runs forward along the lateral side of the masseter muscle. In this course, the duct is surrounded by the buccal fat pad. It takes a steep turn at the border of the masseter and passes through the buccinator muscle, opening into the vestibule of the mouth, between the cheek and the gums, at the parotid papilla, which lies across the second superior molar tooth.

The external carotid artery is a major artery of the head and neck. It arises from the common carotid artery when it splits into the external and internal carotid artery. It supplies blood to the face and neck. The external carotid artery begins opposite the upper border of the thyroid cartilage and, taking a slightly curved course, passes upward and forward and then inclines backward to the space behind the neck of the mandible, where it divides into the superficial temporal and internal maxillary arteries. It rapidly diminishes in size in its course up the neck, owing to the number and large size of the branches given off from it. At its origin, this artery is more superficial and placed nearer the midline than the internal carotid and is contained within the carotid triangle. The external carotid artery is covered by the skin, superficial fascia, platysma, deep fascia and anterior margin of the sternocleidomastoid. It is crossed by the hypoglossal nerve, by the lingual, ranine, common facial and superior thyroid veins; and by the digastric and stylohyoid; higher up it passes deeply into the substance of the parotid gland, where it lies deep to the facial nerve and the junction of the temporal and internal maxillary veins. It is here that it is in danger during surgery of the parotid gland.

The ventricular system of the brain is made up of four ventricles namely; two lateral and a third and forth ventricle. The ventricles are the site of the development of the cerebrospinal fluid. The left and right lateral ventricles are located in each of the brain’s hemispheres. The roof of the lateral ventricles are made up of the fibres of the corpus callosum. This is the structure that would be compressed by the a tumour on the roof of the lateral ventricles.

The pterygoid hamulus is a hook-like process at the lower extremity of the medial pterygoid plate of the sphenoid bone around which the tendon of the tensor veli palatini passes.

The facial muscles generally originate from the facial bones and attach to the skin, in the same plane as the platysma muscle. They are all innervated by cranial nerve VII (the facial nerve). The occipitofrontalis muscle consists of two parts: The occipital belly, near the occipital bone, and the frontal belly, near the frontal bone.

The combined effort of the lateral pterygoid muscles results in the protrusion of the mandible. The lateral pterygoid muscle is a muscle of mastication located superiorly to the medial pterygoid muscle and has two heads. The superior head originates on the infratemporal surface and infratemporal crest of the greater wing of the sphenoid bone, and the inferior head on the lateral surface of the lateral pterygoid plate. The insertion of this muscle is on the front margin of the articular disc of the temporomandibular joint. The unilateral contraction of the pterygoid muscle results in the laterotrusion of the mandible. It is important to note that the lateral pterygoid muscle is the only muscle of mastication that can open the jaw.

Ligamentum venosum is an anterior relation of the liver: The ligamentum venosum, the fibrous remnant of the ductus venosus of the fetal circulation, lies posterior to the liver. It lies in the fossa for ductus venosus that separates the caudate lobe and the left lobe of the liver. The portal triad contains three important tubes: 1. Proper hepatic artery 2. Hepatic portal vein 3. Bile ductules It also contains lymphatic vessels and a branch of the vagus nerve. The bare area of the liver is a large triangular area that is devoid of any peritoneal covering. The bare area is attached directly to the diaphragm by loose connective tissue. This nonperitoneal area is created by a wide separation between the coronary ligaments. The porta hepatis is a fissure in the inferior surface of the liver. All the neurovascular structures (except the hepatic veins) and hepatic ducts enter or leave the liver via the porta hepatis. It contains the sympathetic branch to the liver and gallbladder and the parasympathetic, hepatic branch of the vagus nerve. The caudate lobe (segment I) lies in the lesser sac on the inferior surface of the liver between the IVC on the right, the ligamentum venosum on the left, and the porta hepatis in front

In adults, the spinal cord typically ends between L1/L2 whereas the subarachnoid space extends to approximately the lower border of vertebra S2. Lumbar puncture is performed in the intervertebral space L4/L5 or L3/L4.

The maxillary sinuses usually develop symmetrically. The maxillary sinus ostium drains into the infundibulum which joins the hiatus semilunaris and drains into the middle meatus.

A posterolateral herniation of the disc at the L4 – L5 level would be most likely to damage the fifth lumbar nerve root, not the fourth lumbar nerve root, due to more oblique descending of the fifth lumbar nerve root within the subarachnoid space.

The middle meningeal artery is typically the third branch of the first part of the maxillary artery, one of the two terminal branches of the external carotid artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater and the calvaria. The middle meningeal artery is the largest of the three (paired) arteries that supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery. The anterior branch of the middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an epidural hematoma. An injured middle meningeal artery is the most common cause of an epidural hematoma.

The inferior thyroid artery is an artery in the neck. It arises from the thyrocervical trunk and passes upward, in front of the vertebral artery and longus colli muscle.

The 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 cavernous sinuses and pterygoid plexus, otic ganglion, and occasionally the nervus spinosus and lesser petrosal nerve.

The optic foramen is the opening to the optic canal. The canal is located in the sphenoid bone; it is bounded medially by the body of the sphenoid and laterally by the lesser wing of the sphenoid. The superior surface of the sphenoid bone is bounded behind by a ridge, which forms the anterior border of a narrow, transverse groove, the chiasmatic groove (optic groove). The groove ends on either side in the optic foramen, which transmits the optic nerve and ophthalmic artery into the orbital cavity. Compared to the optic nerve, the ophthalmic artery is located inferolaterally within the canal.

The second pharyngeal arch or hyoid arch, is the second of six pharyngeal arches that develops in fetal life during the fourth week of development and assists in forming the side and front of the neck. Derivatives: Skeletal – From the cartilage of the second arch arises: Stapes, Temporal styloid process, Stylohyoid ligament, and Lesser cornu of the hyoid bone.Muscles: Muscles of face Occipitofrontalis muscle Platysma Stylohyoid muscle Posterior belly of Digastric Stapedius muscle Auricular musclesNerve supply: Facial nerve

Sensory innervation to the external ear is supplied by both cranial and spinal nerves. Branches of the trigeminal, facial, and vagus nerves (CN V, VII, X) are the cranial nerve components, while the lesser occipital (C2, C3) and greater auricular (C2, C3) nerves are the spinal nerve components involved. The lateral surface of the tympanic membrane, the external auditory canal, and the external acoustic meatus are all innervated by nervus intermedius (a branch of CN VII), the auriculotemporal nerve (CN V3), and the auricular branch of the vagus nerve. The concha receives split innervation from nervus intermedius, the auricular branch of the vagus nerve, and the greater auricular (spinal) nerve. Beyond the concha, the anteromedial and anterosuperior parts of the pinna are innervated by the auriculotemporal nerve, and a portion of the lateral helix by the lesser occipital nerve. The greater auricular nerve provides innervation to the area of the pinna inferolateral to the lobule.

The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains: Muscles: thyrohyoid, sternothyroid, sternohyoid muscles Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerve The posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle. Contents: Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus Of the muscles listed in the options, only the anterior scalene is situated within the posterior triangle of the neck.

Infrahyoid muscles are also known as “strap muscles” which connect the hyoid, sternum, clavicle and scapula. They are located below the hyoid bone on the anterolateral surface of the thyroid gland and are involved in movements of the hyoid bone and thyroid cartilage during vocalization, swallowing and mastication. They are composed of four paired muscles, organized into two layers. Superficial layer consists of the sternohyoid and omohyoid Deep layer consists of the sternothyroid and thyrohyoid.

Congenital neck masses are developmental anomalies typically seen in infants or children. Common conditions include thyroglossal duct cysts, branchial cleft cysts, and cystic hygromas. These malformations present as painless neck masses, which can cause dysphagia, respiratory distress, and neck pain due to compression of surrounding structures. The location of the mass depends on the embryological structure the cysts arise from. Diagnosis is made based on clinical findings and imaging results (ultrasound, CT, MRI), which also help in surgical planning. Treatment consists of complete surgical resection to prevent recurrence and complications such as infection or abscess formation. The thyroglossal cyst is present from birth and usually detected during early childhood. It presents as a painless, firm midline neck mass, usually near the hyoid bone, which elevates with swallowing and tongue protrusion. May cause dysphagia or neck/throat pain if the cyst enlarges.