Head Flashcards
Orbicularis oculi
O: Medial orbital margin, medial palpebral ligament, lacrimal bone.
I: Skin around orbit, superior & inferior tarsal plates.
N: temporal and zygomatic branches of parotid plexus.
Corrugator supercilli
O: medial end of superciliary arch.
I: skin superior to supraorbital margin and superciliary arch.
N: temporal branch of parotid plexus.
Orbicularis oris
O: Maxillae and mandible, modiolus.
I: mucous membrane of lips.
N: Buccal branch of parotid plexus.
Levator labii superioris
O: Infra-orbital margin (maxilla).
I: skin of upper lip.
N: Buccal branch of parotid plexus.
Zygomaticus minor
O: zygomatic bone.
I: skin of upper lip.
N: Buccal branch of parotid plexus.
Zygomaticus major
O: zygomatic bone.
I: modiolus.
N: Buccal branch of parotid plexus.
Buccinator
O: maxilla and mandible (alveolar processes), pterygomandibular raphe.
I: modiolus, orbicularis oris.
N: Buccal branch of parotid plexus.
Muscles contributing to modiolus (their distal attachment)
Buccinator, Zygomaticus major, Levator anguli oris, Risorius, Depressor anguli oris.
Occipitofrontalis
Frontal belly: O: epicranial aponeurosis - I: skin and sc tissue of eyebrows and forehead. N: temporal branch of parotid plexus.
Occipital belly: O: Lateral 2/3 of superior nuchal line - I: epicranial aponeurosis. N: Posterior auricular branch of parotid plexus.
Platysma
O: sc tissue of infraclavicular and supraclavicular regions.
I: mandible, modiolus.
N: cervical branch of CNVII (via parotid plexus)
CNV gives sensory respectively motor Innervation to what?
Sensory via pseudounipolar neurons in trigeminal ganglion to the face, bypassed by motor root via multipolar axons to muscles of mastication.
Main cutaneous branch of nasocilliary nerve
Infratrochlear nerve
Innervation of lacrimal gland
Lacrimal nerve, smallest branch of CNV1, receiving secretomotor fibers from zygomaticotemporal nerve (CNV2).
Innervation of parotid gland
Preganglionic parasympathetic secretomotor fibers (from the glossopharyngeal, tympanic, and lesser petrosal nerves) synapse in the otic ganglion. Postganglionic fibers travel with the auriculotemporal nerve and so reach the gland.
LR6 SO4 AO3
Lateral rectus CNVI, Superior oblique CNIV, All others CNIII.
Innervation of superior rectus and levator palpabrae superioris
Superior division of CNIII.
Innervation of medial and inferior rectus and inferior oblique.
Inferior division of CNIII
Boundaries of parotid region
Superiorly: Zygomatic arch.
Posteriorly: Sternocleidomastoid, external ear.
Medially: Ramus of mandible.
Anteriorly: Masseter.
Inferiorly: Inferior border and angle of mandible.
Contents of parotid region
Parotid gland and duct, parotid plexus, retromandibular vein, external carotid artery, m. Masseter.
Arterial supply to nose
- Anterior and posterior ethmoidal aa. - ophthalmic artery.
- Sphenopalatine a. - maxillary artery.
- Greater palatine a. - maxillary artery.
- Septal branch of superior labial a. - facial artery.
What encloses the parotid gland and from what is it derived from?
Parotid sheath, derived from investing layer of deep cervical fascia.
Where does the parotid duct enter the oral cavity?
It pierces the buccinator and enters the oral cavity through a small orifice opposite to the 2nd maxillary molar tooth.
Innervation of parotid gland and sheath
Parotid sheath: Great auricular nerve (C2. C3) and auriculotemporal nerve. Also innervates overlying skin.
Parotid gland:
Parasympathetic: CNIX supplies presynaptic secretory fibers to otic ganglion. Postsynaptic parasympathetic fibers are conveyed from otic ganglion to gland by auriculotemporal nerve. Stimulation produces thin watery saliva.
Sympathetic: Derived from cervical ganglia through external carotid nerve plexus. Vasomotor, reduces secretion of gland.
Sensory fibers by great auricular and auriculotemporal nerves.
Boundaries of temporal fossa
Posteriorly and superiorly: Temporal lines.
Anteriorly: Frontal and zygomatic bones.
Laterally: Zygomatic arch.
Inferiorly: Infratemporal crest.
Boundaries of infratemporal fossa
Laterally: ramus of mandible.
Medially: lateral pterygoid plate.
Anteriorly: posterior aspect of maxilla.
Posteriorly: tympanic plate and mostoid and styloid processes of temporal bone.
Superiorly: inferior surface of greater wing of sphenoid.
Inferiorly: Where medial pterygoid m. attaches to mandible.
Contents of infratemporal fossa
Inferior part of temporalis m. Lateral and medial pterygoid muscles. Maxillary a. Pterygoid venous plexus. Mandibular, inferior alveolar, lingual, buccal, and chorda tympani nerves. Otic ganglion.
Temporomandibular joint
Hinge type of synovial joint, permits gliding and pivoting.
Has an articular disc creating superior and inferior articular cavities.
Pharyngotympanic tube and tensor tympani enters on which wall of middle ear?
Anterior wall.
Pharyngotympanic tube
Connects middle ear with nasopharynx. Consists of a bony part (1/3 nearest to middle ear) and a cartilaginous part (remaining 2/3). Receives innervation from tympanic plexus and tympanic branch of CNIX.
Malleus has which bony features?
Incus articulation, Head of malleus, Neck of malleus, Anterior process, Lateral process, Handle of malleus.
Incus has which features?
Body of incus, Malleus articulation, Short limb, Long limb.
Stapes has which features?
Base of stapes, Anterior limb, Posterior limb, Head of stapes.
Tensor tympani
O: Cartilaginous part of pharyngotympanic tube, greater wing of sphenoid.
I: Handle of Malleus.
N: Mandibular nerve (CNV3).
-Pulls handle of malleus medially which tenses the tympanic membrane, reducing amplitude of oscillations.
Stapedius
O: Inside of pyramidal eminence.
I: Neck of stapes.
N: Nerve to stapedius (CNVII).
-Pulls stapes posteriorly which tightens anular ligament and reducing oscillatory range.
Extrinsics of tongue
Genioglossus, Hyoglossus, Styloglossus: Hypoglossal n. (CNXII), Palatoglossus: Vagus n. (CNX).
Intrinsics of tongue
Superior longitudinal, Inferior longitudinal, Transverse, Vertical.
Kiesselbach area
Area rich in arterial anastomoses in anterior 1/3 of nasal septum - common area of epistaxis.
Innervation of nasal cavity
Posteroinferior portion: Nasal septum: nasopalatine nerve (maxillary n.). Lateral wall: posterior lateral nasal and inferior Iateral nasal branches of greater palatine nerve.
Anterosuperior portion: anterior and posterior ethmoidal nerve, branches of nasocilliary nerve (CNV1).
External nose: external nasal branch of anterior ethmoidal nerve, Infratrochlear nerve, algae of nose supplied by nasal branches of infra-orbital nerve (CNV2).
Which muscle of tongue is not innervated by hypoglossal nerve (CNXII)?
Palatoglossus, innervated by vagus.
Muscles of soft palate
Tensor veli palatini, Levator palatini, Palatoglossus, Palatopharyngeus, Musculus uvulae.
Pharyngeal branch of vagus innervates all but one muscle of the soft palate, which one?
Tensor veli palatini (medial pterygoid nerve, branch of CNV3 via otic ganglion)
Which muscles of the soft palate attaches to the cartilage of pharyngotympanic tube?
Tensor veli palatini, Levator veli palatini.
Blood supply to palate
Greater and lesser palatine arteries from descending palatine artery.
Lesser palatine artery anastomoses with ascending palatine artery (from facial artery).
