Nose & Para nasal sinuses Dr. Ashraf Hussain Had Cleopatra's nose been shorter, the whole face of the world would have changed. (Blaise Pascal (1623 - 1662) French philosopher, mathematician, and physicist) NOSE • • • • • • • External nose Bones Nasal cavity Mucous membrane Olfactory portion Respiratory portion Communications of nasal cavity • • • • Floor Roof Lateral wall Medial wall Olfactory membrane Located on the roof of the nasal cavity. Contains cells/receptors which are in contact with the Olfactory bulb and nerve to provide sense of smell. (5% of nasal cavity area) Relations of nasal cavity Important in the spread of infection Direct continuity with (i) the anterior cranial fossa (via the cribriform plate of the ethmoid bone) (ii) the nasopharynx and, through the pharyngotympanic tube, the middle ear (iii) the paranasal air sinuses (iv) the lacrimal apparatus and conjunctiva. Nasal Mucosa Cross section of nasal mucosal layer. Cilia is beating Functions of Nose • • • • • Olfaction Respiration Filtration of dust Humidification Elimination of secretions from paranasal sinuses and nasolacrimal ducts Arteries supplying the Nose • External Carotid Artery • -Sphenopalatine artery • -Greater palatine artery • -Ascending pharyngeal artery • -Posterior nasal artery • -Superior Labial artery • Internal Carotid Artery • -Anterior Ethmoid artery • -Posterior Ethmoid artery Blood supply • The upper part of the nasal cavity receives its arterial supply from the ethmoidal branches of the ophthalmic artery, a branch of the internal carotid. • The sphenopalatine branch of the maxillary artery, a terminal of the external carotid, supplies the lower part of the cavity. • Just within the vestibule of the nose, on the anteroinferior part of the septum, it links with a septal branch of the facial artery and it is from this zone, Little’s area, that 90% of nosebleeds occur. BLOOD SUPPLY OF MEDIAL WALL OF NOSE BLOOD SUPPLY OF LATERAL WALL OF NOSE Kesselbach’s Plexus/Little’s Area: -Anterior Ethmoid (Opth) -Superior Labial A (Facial) -Sphenopalatine A (IMAX) -Greater Palatine (IMAX) Woodruff’s Plexus: -Pharyngeal & Post. Nasal AA of Sphenopalatine A (IMAX) Epistaxis venous drainage • Veins accompany the arteries • The veins drain downwards into the facial vein and upwards to the ethmoidal tributaries of the ophthalmic veins. Innervation • Sense of smell is via the olfactory nerve, which sends microscopic fibers from the olfactory bulb through the cribiform plate to reach the top of the nasal cavity. • General sensory innervation is by branches of the • Trigeminal nerve (V1 & V2) • Nasociliary nerve (V1) • Nasopalatine nerve (V2) • Posterior nasal branches of Maxillary nerve (V2) • The entire nasal cavity is innervated by autonomic fibers. • Sympathetic innervation to the blood vessels of the mucosa causes them to constrict, while the control of secretion by the mucous glands is carried on postganglionic parasympathetic nerve fibers originating from the facial nerve. Lymphatics • Lymph from anterior regions of the nasal cavities drains forward onto the face by passing around the margins of the nares. These lymphatics ultimately connect with the submandibular nodes. • Lymph from posterior regions of the nasal cavity and the paranasal sinuses drains into upper deep cervical nodes. Some of this lymph passes first through the retropharyngeal nodes. Clinical features • • • • • • Nasal Fractures Epistaxis Rhinitis Deviated nasal septum Nasal polyps Boil on nose Danger area of the face The skin of the external nose and its surrounds contains many sebaceous glands and hair follicles which may become blocked and infected Facial veins, which may become secondarily infected, communicate directly with the ophthalmic veins and hence with the cavernous sinus. For this reason, this zone is often known as the ‘danger area of the face’. Deviated Nasal Septum • The septum is frequently deviated to one or other side, interfering both with inspiration and with drainage of the nose and accessory sinuses. Pathology • Deviation – Usually in cartilagenous part – Different shapes • C shaped • S shaped • Spur – At junction of cartilage and bone Symptoms • Nasal obstruction • Nasal deformity • Sense of smell and taste are disturbed • Recurrent epistaxis Nasal Polyp – Smooth glistening grape like masses • Pale but Protruding polyp may appear pink • Insensitive to probing • Do not bleed on touch – Multiple and bilateral – Broadening of nose – Increased intercanthal distance Paranasal air sinuses • • • • • Air filled spaces in bones Frontal Ethmoidal Sphenoidal Maxillary Sinuses Functions of sinuses • Warm and humidify inspired air • Resonance of voice • Reduce the weight of skull Guess what? Guess what?