Anatomy of Lymphatics in Face

Anatomy

• Krause's glands are accessory lacrimal glands located underneath the eyelid.
• Submandibular nodes are located deep to the investing layer of deep cervical fascia in the submandibular triangle, between the deep fascia and submandibular gland.
• These nodes receive afferents from the centre of the forehead, anterior part of the nasal cavity, frontal, maxillary, and ethmoidal air sinuses, inner canthus, whole of upper lip, and anterior part of the cheek.
• Submandibular nodes also receive efferents of submental nodes and drain into upper and lower deep cervical nodes.

Pharynx

• Killian's dehiscence is a potential gap between the two parts of the inferior constrictor muscle, thyropharyngeous and cricopharyngeous, and is also known as the gateway to tear.
• It is the site for herniation of pharyngeal mucosa in case of pharyngeal pouch.

Middle Ear

• Fossa incudis contains the short process of the incus.
• Head of malleus is attached to epitympanum by the ligament of the head of malleus.
• Long process of incus is attached to the head of the stapes.
• Footplate of stapes lies over the oval window.

Laryngeal Cartilage

• Chorda tympani arises from the intratemporal part of the facial nerve and carries preganglionic secretomotor fibers to the submandibular and sublingual glands.
• It joins the lingual nerve in the infratemporal fossa and carries taste sensations from the anterior 2/3 of the tongue.

Nerve

• Vidian nerve is formed by the union of the greater petrosal nerve and the deep petrosal nerve.

Nasal Cavity

• Woodruff's area is located on the posteriorinferior part of the lateral nasal wall, under the posterior end of the inferior turbinate.
• Sphenopalatine artery anastomoses with the posterior pharyngeal artery in this area.

Inner Ear

• The inner ear consists of a membranous labyrinth enclosed in a bony labyrinth.
• The bony labyrinth consists of the cochlea, vestibule, and semicircular canals.
• The membranous labyrinth consists of the cochlear duct, utricle, saccules, three semicircular ducts, and the endolymphatic duct and sac.

Lymphatic Drainage

• Lymphatic drainage of the thyroid gland is mainly through the Meissner's plexus.

Thymus

• Hassall's corpuscles are found in the medulla of the thymus and are onion-like structures with an intensely eosinophilic core of dead material.

Kidney

• Ducts of Bellini are present in the kidney and are also known as papillary ducts.

Breast

• The breast is a modified sweat gland, specifically an apocrine type of sweat gland.

Respiratory System

• The respiratory rhythm is established in the medulla and can be spoilt by a strong inspiratory drive originating in the apneustic centers.
• The pneumotaxic center of the upper pons and the influence from stretch receptors in the lung via the vagus inhibit inspiratory activity.

Ventilation and Perfusion

• Alveolar ventilation is the amount of inspired air entering the gas-exchange areas (alveoli) per minute during quiet breathing.
• An increase in alveolar ventilation rate decreases the partial pressure of CO2 in alveoli.
• Mismatch of ventilation/perfusion ratio is seen in both the apex and base of the lung.

Cardiovascular System

• The normal electrical axis of the heart lies between -30° and +100°.
• If the axis is more negative than -30°, it is called left axis deviation, whereas if the axis is more positive than +100°, it is called right axis deviation.

Other

• Herring Breuer reflex is an increase in the duration of inspiration.
• Isocapnic exercise is breathing of increased volume of ventilation for a long period.
• Pulmonary vasodilation is caused by histamine.
• Infusion of hypotonic saline increases both ICF and ECF.