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The scalp and superficial temporal region together cover the vault and upper part of the lateral aspect of the skull.
It extends from the eyebrows in front to the superior nuchal lines behind.
Laterally, it extends to the zygomatic arch.
Functionally, it protects the cranial vault and houses superficial arteries and veins important in head and neck surgery.
The highest point on the skull when the head is in anatomical position.
Lies midway between glabella and external occipital protuberance.
Meeting point of coronal and sagittal sutures.
Corresponds to the anterior fontanelle in infants.
Junction of sagittal and lambdoid sutures.
Represents the posterior fontanelle of infancy.
H-shaped junction of frontal, parietal, sphenoid (greater wing), and temporal bones.
Lies 4 cm above the midpoint of the zygomatic arch.
Clinical importance: Related to the anterior branch of the middle meningeal artery.
Junction of parietal, occipital, and mastoid parts of temporal bone.
Overlies transverse–sigmoid sinus junction.
Midline projection at the back of skull; palpable landmark for neck muscle attachments.
Curved ridge extending laterally from the external occipital protuberance.
Provides attachment to trapezius and sternocleidomastoid.
Arching ridge on parietal bone marking the attachment of temporalis fascia and muscle.
Upper line → fascia; lower line → muscle.
Bony bridge connecting zygomatic and temporal bones.
Lies opposite the lower part of the external auditory meatus.
Landmark for middle meningeal artery (crosses 1 inch above it).
Anteriorly: Up to supraorbital margins.
Posteriorly: To superior nuchal lines.
Laterally: Up to zygomatic arches.
S – Skin
Thick, hair-bearing, and richly supplied with sebaceous glands.
Contains sweat glands and hair follicles → prone to infection.
C – Connective Tissue (Superficial fascia)
Dense fibrofatty tissue with vessels and nerves tightly bound by fibrous septa.
Injury causes profuse bleeding due to inability of vessel walls to retract.
A – Aponeurosis (Epicranial aponeurosis)
Strong tendinous sheet connecting frontalis and occipitalis muscles.
Also called galea aponeurotica.
Provides mobility and expression (raising eyebrows).
L – Loose Areolar Tissue
“Danger area” of scalp — allows movement of scalp over pericranium.
Contains emissary veins connecting superficial veins → intracranial sinuses → infection risk.
P – Pericranium
Periosteum of skull bones.
Loosely attached except at sutures (where it continues as sutural ligaments).
Arteries:
From external carotid: Superficial temporal, posterior auricular, occipital.
From internal carotid: Supraorbital, supratrochlear (branches of ophthalmic).
Veins: Follow arteries; communicate via emissary veins with dural sinuses.
Anterior region:
Supratrochlear and Supraorbital (branches of ophthalmic division of trigeminal nerve).
Lateral region:
Zygomaticotemporal (maxillary division), Auriculotemporal (mandibular division).
Posterior region:
Greater occipital (C2), Third occipital (C3), Lesser occipital (C2).
Anterior scalp: Pre-auricular and parotid nodes.
Posterior scalp: Occipital and posterior auricular nodes.
Lateral scalp: Parotid nodes.
Incision: Coronal incision across vertex behind hairline, extend downward in midline.
Reflect skin and superficial fascia together with vessels and nerves.
Note:
The dense connective tissue retains cut arteries open → profuse bleeding.
The epicranial aponeurosis glides over the loose areolar tissue.
The danger area (loose tissue layer) communicates with intracranial sinuses via emissary veins.
Above: Temporal line.
Below: Zygomatic arch.
In front: Frontal process of zygomatic bone.
Behind: Auricle.
Temporalis fascia and superficial temporal vessels and nerve.
Auriculotemporal nerve (branch of mandibular nerve).
Superficial temporal artery – one of the terminal branches of external carotid artery.
Vein – joins maxillary vein → forms retromandibular vein.
Lymphatics – drain to preauricular nodes.
Scalp wounds bleed profusely → dense connective tissue prevents vasoconstriction.
Infection spread:
From loose areolar tissue (danger area) → emissary veins → intracranial venous sinuses → meningitis.
Black eye (periorbital ecchymosis):
Due to collection of blood under loose areolar tissue tracking forward into eyelids.
Sebaceous cysts – common on scalp due to blocked ducts of sebaceous glands.
Scalp avulsion – in accidents, entire scalp can be torn at the loose areolar layer; prompt reattachment possible.
Temporal artery biopsy – for diagnosing giant cell arteritis.
Temporal pulse – felt just above the zygomatic arch, anterior to ear.
Extends from hairline above to chin and base of mandible below.
Laterally up to the auricle.
The forehead belongs to both face and scalp.
Make an incision along the midline of the face, from forehead to chin.
Make horizontal incisions across zygomatic arch and mandible.
Reflect skin laterally with care to preserve:
Facial artery and vein
Parotid duct
Branches of the facial nerve
Highly vascular → facial wounds bleed profusely but heal rapidly.
Rich in sebaceous and sweat glands → causes oily texture and acne.
Skin is thick and elastic due to muscle insertions; wounds gape widely.
Lax in most parts → edema spreads easily, especially in renal disease (starts in eyelids).
Fixed over cartilages (nose, ear) → boils are painful.
Contains:
Facial muscles (inserted into skin).
Vessels and nerves supplying muscles and skin.
Variable fat — abundant in cheeks (buccal pads) for sucking in infants.
Deep fascia: Absent except:
Over parotid gland (forms parotid fascia).
Over buccinator muscle (forms buccopharyngeal fascia).
Subcutaneous muscles responsible for facial expressions.
Develop from second branchial arch mesoderm → supplied by facial nerve (VII cranial).
Represent remnants of panniculus carnosus (muscle sheet in lower animals).
Act as sphincters and dilators around three facial openings:
Palpebral fissure: orbicularis oculi (sphincter), frontalis (dilator).
Oral fissure: orbicularis oris (sphincter); other muscles act as dilators.
Nostrils: dilator naris, compressor naris, depressor septi.
1. Muscles of the Scalp
Occipitofrontalis – elevates eyebrows, wrinkles forehead.
2. Muscles around Auricle
Auricularis anterior, superior, posterior – vestigial, move auricle slightly.
3. Muscles of Eyelids and Orbit
Orbicularis oculi: sphincter; closes eyelids.
Corrugator supercilii: produces vertical wrinkles over nose.
Levator palpebrae superioris: elevates upper eyelid (not a facial muscle).
4. Muscles of the Nose
Procerus, Compressor naris, Dilator naris, Depressor septi.
5. Muscles around Mouth
Orbicularis oris: sphincter; closes lips.
Buccinator: aids in blowing and chewing; pierced by parotid duct.
Levator labii superioris, Zygomaticus major/minor, Levator anguli oris: elevate mouth angle/lip.
Depressor anguli oris, Depressor labii inferioris, Mentalis: depress lip.
Risorius: retracts mouth angle (smile).
Platysma: tenses skin of neck, depresses mandible in fright.
6. Modiolus (corner of mouth)
Fibromuscular node 1.25 cm lateral to mouth angle.
Formed by interlacing of 5 muscles:
Zygomaticus major, Buccinator, Levator anguli oris, Risorius, Depressor anguli oris.
Facial nerve (VII cranial) divides within the parotid gland into five terminal branches:
Temporal → Frontalis, orbicularis oculi (upper part).
Zygomatic → Orbicularis oculi (lower eyelid).
Buccal → Muscles of upper lip, cheek.
Marginal mandibular → Lower lip muscles.
Cervical → Platysma.
(Mnemonic: To Zanzibar By Motor Car)
Test: Place wrist on ear, spread fingers over face—each finger represents a branch.
Derived from Trigeminal nerve (V cranial):
Ophthalmic division (V1): Supraorbital, supratrochlear, infratrochlear, external nasal.
Maxillary division (V2): Infraorbital, zygomaticofacial, zygomaticotemporal.
Mandibular division (V3): Buccal, auriculotemporal, mental nerves.
Facial wounds:
Bleed freely but heal well due to rich blood supply.
Facial nerve palsy (Bell’s palsy):
Paralysis of muscles of expression → face deviates to opposite side; inability to close eyelid, drooping of mouth, loss of nasolabial fold.
Parotid gland injury:
May affect terminal branches of facial nerve within the gland.
Buccinator function:
Paralysis causes food to accumulate between cheek and gums.
Infection and edema:
Spread rapidly due to loose areolar tissue and rich blood supply.
Angular vein (danger area):
Communication between facial vein and cavernous sinus → risk of intracranial spread of infection.
“Black eye”:
Blood from scalp injury tracks to eyelids through loose tissue of face.
Plastic surgery:
Excellent healing and minimal scarring due to vascularity and elasticity of skin.
The face is richly vascular, ensuring rapid healing and excellent results in plastic surgery.
Blood supply is mainly from branches of the external carotid artery, assisted by branches of ophthalmic artery (internal carotid).
Facial artery – chief artery of the face.
Transverse facial artery – branch of superficial temporal artery.
Small branches – accompany cutaneous nerves (from ophthalmic, maxillary, and superficial temporal arteries).
Identify facial artery at the lower border of the mandible, anterior to the masseter muscle — known as “Anaesthetist’s artery” (palpable point).
Trace its tortuous course upwards and medially across the face:
Crosses body of mandible → angle of mouth → side of nose → medial angle of eye.
Deep to zygomaticus major and levator labii superioris, but superficial to buccinator.
From external carotid artery, just above the greater cornu of hyoid bone.
Cervical part → through submandibular region, enters face by winding around mandible.
Facial part → passes obliquely across face up to medial angle of eye.
Cervical branches:
Ascending palatine, tonsillar, submental, glandular branches.
Facial branches:
Inferior labial
Superior labial
Lateral nasal
Angular (terminal branch).
Supplies lips, nose, cheek, and lower eyelid.
Formation: Union of supratrochlear and supraorbital veins near medial angle of eye.
Continuation of angular vein down the face.
Runs behind the facial artery, straight and superficial.
Termination: Drains into internal jugular vein.
Correspond to branches of the facial artery.
Important communications:
Angular vein ↔ superior ophthalmic vein ↔ cavernous sinus.
Deep facial vein ↔ pterygoid venous plexus.
Danger area of the face:
Bounded by nose and upper lip triangle.
Infection can spread from facial vein → angular vein → cavernous sinus → cavernous sinus thrombosis (fatal).
Anaesthetist’s artery:
Facial artery palpable where it crosses mandible.
Facial vein injuries:
No valves → spread of infection possible in both directions.
Facial bleeding:
Profuse due to rich anastomoses; easily controlled by pressure.
→ Pre-auricular (parotid) lymph nodes.
→ Submandibular lymph nodes.
→ Submental lymph nodes.
→ Deep cervical nodes.
Clinical note:
In carcinoma of lower lip, metastasis occurs to submental nodes;
In upper lip, to submandibular nodes.
Two movable folds guarding the palpebral fissure.
Skin: Thin, delicate, hairless.
Superficial fascia: Very loose → rapid swelling in edema or inflammation.
Orbicularis oculi: Closes eyelids.
Tarsal plates: Dense fibrous plates giving shape and firmness.
Tarsal glands (Meibomian glands):
Modified sebaceous glands opening at lid margins; prevent tear overflow.
Conjunctiva: Thin mucous membrane lining inner surface of lids.
Motor:
Orbicularis oculi → Facial nerve (VII).
Levator palpebrae superioris → Oculomotor nerve (III).
Superior tarsal (Müller’s) muscle → Sympathetic fibers.
Sensory:
Upper lid → Supraorbital, supratrochlear, lacrimal, infratrochlear (V1).
Lower lid → Infraorbital (V2).
Arteries: Ophthalmic artery (from internal carotid).
Veins: Ophthalmic veins → cavernous sinus.
Stye: Acute infection of eyelash follicle or gland of Zeis.
Chalazion: Chronic inflammation of Meibomian gland.
Ptosis: Drooping of upper eyelid due to paralysis of:
Oculomotor nerve (complete ptosis) or
Sympathetic fibers (partial ptosis).
Blepharospasm: Involuntary eyelid closure from facial nerve irritation.
Black eye: Blood spreads to eyelid from scalp injury (loose areolar tissue).
Conjunctivitis: Redness due to dilated conjunctival vessels.
The lacrimal apparatus maintains the tear film and drainage system of the eye.
Its main function is lubrication, protection from dust, and nutrition of cornea and conjunctiva.
Lacrimal gland – secretes tears.
Lacrimal ducts – convey tears to the conjunctival sac.
Conjunctival sac – space between eyeball and eyelid.
Lacrimal canaliculi – small ducts draining tears from puncta.
Lacrimal sac – tear reservoir at medial angle of eye.
Nasolacrimal duct – drains tears into inferior meatus of the nose.
Position:
Lies in the lacrimal fossa of the frontal bone in the superolateral angle of orbit.
Size: ~20 mm × 12 mm × 5 mm.
Parts:
Orbital part: Large, above the aponeurosis of levator palpebrae superioris.
Palpebral part: Small, below the aponeurosis.
Separated by levator aponeurosis, but connected by ducts.
Ducts:
About 10–12 small ducts open into the superior fornix of conjunctiva.
Sensory: Lacrimal nerve (from ophthalmic division, V₁).
Parasympathetic (secretomotor):
From lacrimal nucleus (facial nerve) → greater petrosal nerve → nerve of pterygoid canal → pterygopalatine ganglion → zygomatic branch of V₂ → lacrimal nerve → gland.
Sympathetic: From internal carotid plexus via deep petrosal nerve → same route.
Lacrimal artery (branch of ophthalmic artery).
Vein: Drains into superior ophthalmic vein.
Reflect the upper eyelid laterally to expose the superolateral part of orbit.
Locate the lacrimal gland in the lacrimal fossa of frontal bone.
Identify ducts entering superior fornix.
Follow medial drainage route:
Lacrimal puncta → canaliculi → sac → nasolacrimal duct → inferior meatus.
Epiphora:
Overflow of tears due to blockage in nasolacrimal duct (common in elderly).
Dacryocystitis:
Infection of lacrimal sac → swelling at medial canthus; may form abscess or fistula.
Dry eye (keratoconjunctivitis sicca):
Due to lacrimal gland hyposecretion or facial nerve lesion.
Neonatal dacryocystitis:
Congenital blockage of nasolacrimal duct at valve of Hasner.
Crocodile tears syndrome:
Misrouted parasympathetic fibers after facial nerve injury → lacrimation during eating.
Lacrimal gland tumors:
Cause proptosis and inferomedial displacement of eyeball.
Develops mainly between 4th and 10th weeks of intrauterine life.
Derived from frontonasal prominence and first pharyngeal arch components.
Frontonasal process:
Forms forehead, bridge of nose, and medial and lateral nasal prominences.
Maxillary processes (from first arch):
Form cheeks, lateral part of upper lip, and upper jaw.
Mandibular processes (from first arch):
Fuse to form lower lip and lower jaw.
Nasal placodes appear on frontonasal process → become nasal pits.
Medial nasal prominences fuse → form intermaxillary segment → gives rise to:
Philtrum of upper lip
Premaxilla
Primary palate
Lateral nasal prominences → form sides (alae) of nose.
Maxillary processes grow medially → fuse with medial nasal prominences forming:
Upper lip (excluding philtrum)
Upper jaw
Secondary palate
Upper lip: Fusion of two maxillary and two medial nasal prominences.
Lower lip and jaw: From two mandibular prominences.
Cheeks: Maxillary processes.
Nose:
Bridge → frontonasal process.
Dorsum and sides → lateral nasal processes.
Tip and nasal septum → medial nasal processes.
Alae → lateral nasal processes.
Cleft lip: Non-fusion of medial nasal and maxillary processes.
Oblique facial cleft: Failure of fusion between lateral nasal and maxillary processes.
Median cleft lip: Non-fusion of two medial nasal processes.
Macrostomia: Incomplete fusion of maxillary and mandibular processes (large mouth).
Microstomia: Excessive fusion → small mouth.
Cleft lower lip: Rare, due to failure of mandibular fusion.
Facial development guided by interplay of gene expression gradients and signaling pathways.
Key molecular factors:
SHH (Sonic hedgehog): Controls midline fusion and frontonasal process outgrowth.
FGFs (Fibroblast growth factors): Regulate proliferation in facial prominences.
BMPs (Bone morphogenetic proteins): Induce nasal placode formation.
TGF-β and MSX genes: Govern epithelial–mesenchymal interactions.
Retinoic acid gradients: Critical for symmetry; imbalance causes craniofacial anomalies.
Homeobox genes (DLX, HOX): Determine regional identity of facial arches.
Clinical correlation:
Mutations in SHH → holoprosencephaly (single midline structure).
Mutations in FGF or BMP signaling → cleft lip/palate or craniofacial dysmorphia.
Mnemonic — “Giant Cats Can Sing Naturally”
G → Gland (lacrimal gland)
C → Canaliculi (superior and inferior)
C → Conjunctival sac
S → Sac (lacrimal)
N → Nasolacrimal duct
Mnemonic — “Face Loves Pretty Tears”
F → Facial nerve (parasympathetic source)
L → Lacrimal nucleus → greater petrosal nerve
P → Pterygopalatine ganglion (relay station)
T → Terminal lacrimal nerve (branch of V₁)
Mnemonic — “Five Prominent Parts Make Faces”
F → Frontonasal process
P → Paired maxillary processes
P → Paired mandibular processes
Mnemonic — “Phil Prepares Palate”
Phil → Philtrum of upper lip
Prepares → Premaxilla
Palate → Primary palate
Mnemonic — “Lateral → Lateral walls of Nose”
Form the alae (sides) of nose.
Mnemonic — “Upper Lip and Tip”
Area between nose and upper lip — infections here spread to cavernous sinus via angular vein.
Lacrimal gland lies in the lacrimal fossa of the frontal bone, with orbital and palpebral parts.
Parasympathetic fibers to the lacrimal gland originate from the facial nerve, relaying in the pterygopalatine ganglion.
Tears drain through the puncta → canaliculi → sac → nasolacrimal duct → inferior meatus of nose.
Valve of Hasner guards the opening of the nasolacrimal duct; failure to open causes neonatal dacryocystitis.
Epiphora = overflow of tears; dacryocystitis = inflammation of lacrimal sac.
Development of face begins in the 4th week from five prominences — one frontonasal and paired maxillary and mandibular.
Medial nasal processes form philtrum, premaxilla, and primary palate.
Lateral nasal processes form the sides (alae) of nose.
Maxillary processes fuse with medial nasal to form upper lip and secondary palate.
Mandibular processes fuse in the midline to form lower lip and mandible.
Cleft lip results from non-fusion of maxillary and medial nasal processes.
Cleft palate occurs due to failure of fusion of palatine shelves.
Craniofacial anomalies often result from disruption of SHH, FGF, BMP, or retinoic acid signaling.
The nasolacrimal duct develops from a solid cord of ectoderm in the naso-optic groove that later canalizes.
The nasal placodes invaginate to form nasal pits, which later become the nostrils.
Face develops faster than brain; therefore, malformations often have both cranial and facial involvement.
Medial nasal fusion failure → median cleft lip; lateral nasal fusion failure → oblique facial cleft.
The facial artery forms the chief arterial supply to face; facial vein communicates with cavernous sinus via angular vein.
Lacrimal secretion increases by parasympathetic stimulation (crying, emotion, irritation).
Tears contain lysozyme, which destroys bacterial cell walls, providing antimicrobial defense.
Cause:
Blockage in nasolacrimal duct or puncta prevents tear drainage.
Symptoms:
Constant tearing and wetness at medial canthus.
Skin excoriation from chronic moisture.
Anatomical Basis:
Tears accumulate in conjunctival sac → cannot drain via lacrimal passages.
Treatment:
Dacryocystorhinostomy (DCR) — surgical creation of new passage between lacrimal sac and nasal cavity.
Cause:
Infection due to stasis of tears in obstructed sac.
Clinical Features:
Painful swelling at medial canthus of eye.
Tenderness, redness, pus discharge on pressure over sac.
Complication:
May burst → lacrimal fistula discharging tears on cheek.
Treatment:
Drainage and antibiotics; chronic cases → DCR surgery.
Mechanism:
Misrouted regeneration of facial nerve fibers after injury.
Effect:
Parasympathetic fibers to lacrimal gland are wrongly connected to salivary fibers.
Clinical Feature:
Lacrimation during eating (“gustatory lacrimation”).
Relevance:
Occurs after Bell’s palsy or facial nerve trauma.
Cause:
Failure of canalization of nasolacrimal duct at valve of Hasner in newborns.
Clinical Feature:
Mucopurulent discharge from eyes since birth.
Treatment:
Massage of lacrimal sac; if persistent → probing to open the duct.
Cause:
Non-fusion of maxillary process with medial nasal process.
Types:
Unilateral or bilateral; complete or incomplete.
Effect:
Gap in upper lip, may extend to nostril.
Functional Problems:
Difficulty in sucking and speech.
Treatment:
Surgical correction (cheiloplasty) after 3 months of age.
Cause:
Failure of fusion of palatine shelves (maxillary processes).
Clinical Feature:
Communication between oral and nasal cavities.
Regurgitation of fluids through nose.
Nasal tone of voice.
Treatment:
Surgical closure (palatoplasty) between 9–18 months.
Cause:
Failure of fusion between lateral nasal and maxillary processes.
Appearance:
Cleft extending from upper lip to medial angle of eye.
Accompanied by:
Defective formation of nasolacrimal duct.
Clinical Note:
Rare; often associated with severe craniofacial anomalies.
Cause:
Failure of fusion between two medial nasal processes.
Feature:
Midline cleft in upper lip, sometimes extending into nasal septum.
Association:
May accompany holoprosencephaly (defective forebrain division).
Macrostomia: Incomplete fusion of maxillary and mandibular processes → abnormally large mouth.
Microstomia: Excessive fusion of same processes → abnormally small mouth.
Clinical Significance: Both may coexist with facial clefts or mandibular anomalies.
Cause:
Mutation in Sonic hedgehog (SHH) gene → failure of midline patterning.
Clinical Spectrum:
Single central incisor → cyclopia (severe).
May include median cleft face, hypotelorism, and agenesis of corpus callosum.
Cause:
Unequal development or hypoplasia of one side of face.
Common after first arch syndromes (e.g., Treacher Collins).
Effect:
Distorted oral commissure and jaw alignment.
Deficiency of aqueous layer: due to lacrimal gland dysfunction.
Deficiency of lipid layer: due to meibomian gland dysfunction.
Deficiency of mucin layer: due to conjunctival goblet cell loss.
Effect:
Dry eye syndrome, corneal ulceration, irritation.
It is the system of structures that produce, secrete, and drain tears from the eye.
Components: Lacrimal gland, ducts, canaliculi, lacrimal sac, and nasolacrimal duct.
In the lacrimal fossa of the frontal bone, at the superolateral angle of the orbit.
Orbital part: Large, lies above levator palpebrae aponeurosis.
Palpebral part: Small, lies below the aponeurosis.
Through 10–12 small ducts from the palpebral part of the lacrimal gland, opening into the superior conjunctival fornix.
Sensory: Lacrimal branch of ophthalmic nerve (V₁).
Parasympathetic (secretomotor):
From facial nerve (VII) → greater petrosal nerve → nerve of pterygoid canal → pterygopalatine ganglion → zygomatic branch (V₂) → lacrimal nerve → gland.
Sympathetic: From internal carotid plexus.
By the lacrimal branch of ophthalmic artery (from internal carotid).
Into the inferior meatus of the nose, guarded by the valve of Hasner.
Lubricate and clean the eyeball.
Nourish the cornea and conjunctiva.
Contain lysozyme — antibacterial enzyme.
Blockage of the nasolacrimal duct or lacrimal puncta.
Inflammation of the lacrimal sac, often due to nasolacrimal duct obstruction.
The upper lip and lower part of the nose.
Infections here can spread via angular vein → superior ophthalmic vein → cavernous sinus, leading to cavernous sinus thrombosis.
From five facial prominences:
Frontonasal process
Paired maxillary processes
Paired mandibular processes
Nasal placodes are ectodermal thickenings on the frontonasal process.
Invaginate to form nasal pits, which develop into nostrils and nasal cavities.
From two medial nasal and two maxillary processes.
Philtrum from medial nasal processes.
Rest of upper lip from maxillary processes.
By fusion of two mandibular processes.
By maxillary processes on either side.
Philtrum of upper lip
Premaxilla
Primary palate
Nasal septum
Alae (sides) of the nose
Lateral walls of nasal cavities
Failure of fusion between medial nasal and maxillary processes.
Failure of fusion of the palatine shelves from maxillary processes.
A cleft extending from upper lip to medial angle of eye, due to failure of fusion between lateral nasal and maxillary processes.
Failure of fusion between two medial nasal processes, producing a midline defect.
Macrostomia: Incomplete fusion of maxillary and mandibular processes → large mouth.
Microstomia: Excessive fusion → small mouth.
Sonic Hedgehog (SHH) gene — regulates frontonasal process fusion and midline patterning.
It regulates the anterior-posterior axis; imbalance causes cleft lip/palate and other anomalies.
Prevents regurgitation of nasal contents into the nasolacrimal duct.
It relays parasympathetic fibers to lacrimal gland, nasal glands, and palatine glands.
Lipid layer – from Meibomian glands (prevents evaporation).
Aqueous layer – from lacrimal gland (provides nutrients).
Mucin layer – from goblet cells (spreads tears evenly).
Failure of canalization of nasolacrimal duct at the valve of Hasner.
Cause feeding and speech difficulties.
Associated with nasal and maxillary maldevelopment.
Require surgical correction early in life.
1. The lacrimal gland is located in the:
a) Sphenoid bone
b) Ethmoid bone
✅ c) Frontal bone
d) Maxilla
2. The nasolacrimal duct opens into the:
a) Middle meatus of nose
b) Superior meatus of nose
✅ c) Inferior meatus of nose
d) Common meatus
3. Parasympathetic fibers to lacrimal gland relay in the:
a) Otic ganglion
✅ b) Pterygopalatine ganglion
c) Submandibular ganglion
d) Ciliary ganglion
4. The valve guarding the opening of nasolacrimal duct is:
✅ a) Valve of Hasner
b) Valve of Krause
c) Valve of Bochdalek
d) Valve of Kerckring
5. The facial nerve supplies secretomotor fibers to:
✅ a) Lacrimal gland
b) Parotid gland
c) Sublingual gland
d) Thyroid gland
6. The nerve carrying secretomotor fibers to lacrimal gland is:
✅ a) Lacrimal nerve
b) Auriculotemporal nerve
c) Zygomaticotemporal nerve
d) Infraorbital nerve
7. The lacrimal gland drains into the:
a) Inferior fornix
✅ b) Superior fornix of conjunctiva
c) Caruncle
d) Nasal cavity
8. The nasolacrimal duct develops from:
✅ a) Ectodermal cord in naso-optic groove
b) Endodermal pouch
c) Mesodermal condensation
d) Neural crest
9. Cleft lip results from failure of fusion between:
✅ a) Maxillary and medial nasal processes
b) Medial and lateral nasal processes
c) Two maxillary processes
d) Mandibular processes
10. Cleft palate results from failure of fusion of:
✅ a) Palatine shelves
b) Medial nasal processes
c) Lateral nasal processes
d) Mandibular arches
11. The upper lip is formed by:
✅ a) Maxillary and medial nasal processes
b) Lateral nasal processes only
c) Mandibular processes
d) Frontonasal process alone
12. The lower lip develops from:
✅ a) Fusion of mandibular processes
b) Maxillary and medial nasal processes
c) Lateral nasal processes
d) Frontal process
13. The alae (sides) of nose are derived from:
✅ a) Lateral nasal processes
b) Medial nasal processes
c) Maxillary processes
d) Mandibular processes
14. The philtrum of upper lip is derived from:
✅ a) Medial nasal processes
b) Maxillary processes
c) Mandibular processes
d) Lateral nasal processes
15. The premaxilla is derived from:
✅ a) Intermaxillary segment (medial nasal fusion)
b) Maxillary process
c) Lateral nasal process
d) Mandibular process
16. The frontonasal process gives rise to:
✅ a) Forehead and bridge of nose
b) Philtrum
c) Upper jaw
d) Mandible
17. The oblique facial cleft results from failure of fusion between:
✅ a) Lateral nasal and maxillary processes
b) Medial nasal and maxillary processes
c) Mandibular and maxillary processes
d) Two medial nasal processes
18. The median cleft lip results from failure of fusion between:
✅ a) Two medial nasal processes
b) Medial and maxillary processes
c) Lateral nasal and maxillary processes
d) Two maxillary processes
19. The palatine shelves are derivatives of which embryonic structure?
✅ a) Maxillary process
b) Mandibular process
c) Medial nasal process
d) Frontonasal process
20. The most common cause of congenital dacryocystitis is:
✅ a) Failure of canalization at valve of Hasner
b) Infection of lacrimal gland
c) Facial nerve lesion
d) Overproduction of tears
21. Crocodile tears (Bogorad syndrome) occur due to:
✅ a) Misrouting of facial nerve fibers
b) Damage to glossopharyngeal nerve
c) Lacrimal gland tumor
d) Pterygopalatine ganglion lesion
22. Which molecular signal regulates midline facial fusion?
✅ a) SHH (Sonic Hedgehog)
b) BMP
c) FGF
d) Retinoic acid
23. Which gene regulates the patterning of the first pharyngeal arch?
✅ a) DLX genes
b) SHH
c) HOX A5
d) MSX-1
24. Which bone develops from the frontonasal process?
✅ a) Frontal bone
b) Maxilla
c) Mandible
d) Palatine bone
25. Failure of development of nasal placodes leads to:
✅ a) Absence of external nose (arhinia)
b) Hypertelorism
c) Cleft palate
d) Cleft lip
Lacrimal gland
Lacrimal ducts
Lacrimal canaliculi
Lacrimal sac
Nasolacrimal duct
In the lacrimal fossa of the frontal bone, at the superolateral angle of the orbit.
Orbital part (large)
Palpebral part (small)
Into the superior conjunctival fornix.
Sensory: Lacrimal nerve (V₁)
Secretomotor: Facial nerve (via greater petrosal → pterygopalatine ganglion → zygomatic → lacrimal)
Sympathetic: From internal carotid plexus
To secrete tears that lubricate, cleanse, and protect the eyeball.
Lacrimal gland → ducts → conjunctival sac → puncta → canaliculi → sac → nasolacrimal duct → inferior meatus.
The valve of Hasner, at the lower end of the duct.
Obstruction of the nasolacrimal duct or lacrimal punctum.
Inflammation of the lacrimal sac, often due to nasolacrimal duct obstruction.
From an ectodermal cord in the naso-optic groove, between maxillary and lateral nasal processes.
During the 4th week of intrauterine life.
Frontonasal process
Paired maxillary processes
Paired mandibular processes
Ectodermal thickenings on frontonasal process.
Form nasal pits, which later become nostrils and nasal cavities.
Fusion of two medial nasal and two maxillary processes.
Fusion of two mandibular processes.
Philtrum of upper lip
Premaxilla
Primary palate
Nasal septum
Alae (sides) of nose
Lateral walls of nasal cavity
Failure of fusion between medial nasal and maxillary processes.
Failure of palatine shelves (from maxillary processes) to fuse in midline.
Failure of fusion between lateral nasal and maxillary processes.
Failure of fusion between two medial nasal processes.
Macrostomia: Incomplete fusion of maxillary and mandibular processes.
Microstomia: Excessive fusion of the same processes.
Sonic Hedgehog (SHH) gene.
FGF, BMP, and TGF-β signaling pathways.
Results in holoprosencephaly, with midline facial defects such as single central incisor or cyclopia.
It regulates anterior–posterior patterning; imbalance causes cleft lip/palate.
Relay station for parasympathetic fibers to lacrimal, nasal, and palatine glands.
The lacrimal part of orbicularis oculi — acts as a “tear pump.”
Cleft lip
Cleft palate
Oblique facial cleft
Median cleft lip
Macrostomia
Microstomia
Hypotelorism
Arhinia
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