Notes for Dr. Manions Face and Scalp lecture:

The boundaries of the face are from the chin to the hairline and anterior to the ear. The frontalis and occipitalis muscle are connected to each other by the galea aponeurotica and are responsible for movement of the scalp. The orbicularis oculi is responsible for closing the eyelids tightly. (Part is on the skull and part is on the eyelid. The orbicularis oris is responsible for purching the lips and closing the mouth. The platysma muscle is responsible for tensing the neck.Note: ALL OF THE MUSCLES PREVIOUSLY MENTIONED ARE INNERVATED BY THE FACIAL NERVE. The buccinator muscle is responsible for compressing the cheeks and is pierced by the parotid duct. (The parotid duct leaves the parotid gland and runs along the massetter muscle, when it reaches the anterior border of the massetter muscle it turns about 90 degrees to pierce the buccinator muscle.) NOTE: THE PAROTID DUCT DOES NOT OPEN DIRECTLY INTO THE ORAL CAVITY, IT OPENS INTO THE BUCCAL CAVITY WHICH IS LOCATED BETWEEN THE CHEEKS AND TEETH. THE PAROTID GLAND IS THE BIGGEST SALIVERY GLAND! Where the upper and lower eyelids meet each other is called the canthus (medial and lateral canthus). There are two types of conjunctiva. The bulbar conjunctiva is located on the eye ball itself and is innervated by the ophthalmic nerve. The palpebral conjuctiva is the part of the conjunctiva located behind the eyelids and is innervated by the ophthalmic nerve (upper lid) and the infraorbital nerve (lower lid). (NOTE: THE INFRAORBITAL NERVE IS A BRANCH OF THE MAXILLARY NERVE WHICH IS A BRANCH OF THE TRIGEMINAL NERVE). When the bulbar conjunctiva crosses the cornea, the epithelium changes and it has NO BLOOD VESSELS but it does have lots of naked nerve endings. The bulbar conjunctiva is HIGHLY VASCULARIZED. The palpebral conjunctiva is continuous with the bulbar conjuctiva at the superior and inferior fornix! THE MAJOR SKELETAL MUSCLE THAT IS RESPONSIBLE FOR RAISING THE EYELID IS THE LEVATOR PALPEBRAE SUPERIORIS WHICH IS INNERVATED BY THE OCULOMOTOR NERVE. THE MAJOR SMOOTH MUSCLE RESPONSIBLE FOR KEEPING THE EYELIDS OPEN AS THE DAY PROGRESSES IS THE SUPERIOR TARSAL MUSCLE WHICH IS INNERVATED BY SYMPATHEITC NERVES FROM THE SUPERIOR CERVICAL GANGLION!!!) The orbital portion and palpebral portion of the orbicularis oculi meet at the medial palpebral ligament which attaches to a bone in the orbit. Within the tarsal plate of the eye lids, one would find sebaceous glands! The orbital septum attaches from the rim of the orbit to the tarsal plate. The tarsal plate is anchored medially and laterally to the orbit by the medial and lateral palpebral ligaments. The medial palpebral ligmament splits and surrounds the lacrimal sac. As the eyelids open and close, the split ligament squeezes on the lacrimal sac which is important for lubrication of the eyes. The lacrimal gland is actually split by the tendon of the superior tarsal muscle giving an orbital portion and a palpebral portion. The palpebral portion is actually built into the eyelid. (FOUND IN THE UPPER LATERAL PORTION OF THE EYE) THE DRAINAGE OF TEARS IS AS FOLLOWS: TEARS DRAIN IN TO THE SUPERIOR AND INFERIOR LACRIMAL PUNCTA WHICH DRAINS INTO THE SUPERIOR AND INFERIOR LACRIMAL CANALICULI. THE LACRIMAL CANALICULI DRAINS INTO THE LACRIMAL SAC WHICH CONTINUES AS THE NASOLACRIMAL DUCT WITH THE NASOLACRIMAL CANAL. THE TEARS EVENTUALLY REACH THE INFERIOR NASAL CONCHA WHERE IT DRAINS INTO THE INFERIOR NASAL MEATUS. The lacrimal gland itself drains through ducts located within the superior fornix of the conjunctiva. COMPONENTS OF A TEAR DROP: MOST OF THE TEAR IS AN AQUEOUS MATERIAL PRODUCED BY THE LACRIMAL GLAND. THERE IS A MUCOUS PORTION PRODUCED BY CONJUNCTIVAL GOBLET CELLS. LASTLY THERE IS A SMALL LIPID PORTION PRODUCED BY MEIBOMIAN GLANDS WHICH ARE THOSE SEBACOUS GLANDS LOCATED WITHIN THE TARSAL PLATE! Because the lipid portion is HYDROPHOBIC, when the eyelids close it helps push the aqueous portion toward the medial portion of the eye to be picked up by the lacrimal puncta. When referring to the nose, the nasal bones form the bridge of the nose. The nasal septum is broken up into a cartilaginous septum and a bony portion. The bony portion is the vomer bone and the perpendicular plate of the ethmoid bone. The cartilaginous portion fills a little gap between the perpendicular plate of the ethmoid bone and the vomer bone. (A small portion of the palatine bone also makes a vertical portion of the nasal septum). SCALP also stands for Skin, dense Connective tissue, Aponeurosis, Loose connective tissue, and Pericranium. (THE APONEUROSIS IS THE GALEA APONEUROTICA AND THE PERICRANIUM IS SIMPLY THE PERIOSTEUM OF THE SKULL). The facial artery supplies the entire anterior portion of the face. It gives off an inferior mental branch, inferior labial, superior labial, lateral nasal, and angular artery. (named from inferior to superior) It is highly coiled because it allows for the mouth to open and close without itself being damaged. Another portion of the head is supplied by branches of the external carotid artery. The external carotid artery gives off the occipital artery, posterior auricular artery, maxillary artery, and superior temporal artery. (of course there are more branches of the external carotid artery but they are found in the neck region). NOTE THAT THE TRANSVERSE FACIAL ARTERY IS NOT PART OF THE FACIAL ARTERY. THE TRANSVERSE FACIAL ARTERY IS ACTUALLY A BRANCH OF THE SUPERFICAL TEMPORAL ARTERY WHEREAS THE FACIAL ARTERY IS A DIRECT BRANCH OF THE EXTERNAL CAROTID ARTERY. Other sources of supply to the head are: the infraorbital artery which comes out of the infraorbital foramen is a branch of the maxillary artery, the supraorbital and supratrochlear artery which comes out of the orbit as branches of the internal carotid artery. The supraorbital, supratrochlear, superficial temporal, posterior auricular, and occipital artery anastamose in the scalp!!!! The part of the facial nerve that comes out of the stylomastoid foramen is PURELY MOTOR!!! The sensory sensation of the face is provided by the trigeminal nerve by its ophthalmic, maxillary, and mandibular branches. The posterior portion of the scalp is innervated by the greater and lesser occipital nerves and the auriculotemporal nerve which is a branch of the maxillary nerve, a branch of the trigeminal nerve. On the slide with the guy that has the lower half of the right side of his face paralyzed, it is a CNS defect. If it were a PNS defect, the ENTIRE half of his face would have been paralyzed because the facial nerve is the only nerve that supplies the motor function of the face. Branches of the facial nerve appear to be sprouting out of the parotid gland. Within the parotid gland, the maxillary and superficial temporal veins join to form the retromandibular vein which is the start of the external jugular vein. (IT BECOMES THE EXTERNAL JUGULAR VEIN WHEN IT PICKS UP THE POSTERIOR AURICULAR VEIN!!!) Also within the parotid gland, one would find where the external carotid artery divides into its last two branches, maxillary and superficial temporal arteries. (NOTE THE MAXILLARY ARTERY GOES INTO THE INFRATEMPORAL FOSSA). NOTE THAT THE MAXILLARY ARTERY GIVES RISE TO THE MIDDLE MENINGEAL ARTERY WHICH IS THE ARTERY COMMONLY RUPTURED DURING EPIDURAL HEMATOMAS WHEN IT GETS LACERATED AT THE PTERION!