Boards Prep: Ocular Anatomy: Book Flashcards
(168 cards)
Define the following:
- Telecanthus
- Poliosis
- Madarosis
a. Most common causes (3)
b. Most Dangerous cause? - Trichiasis
- Phthiriasis Palpebrarum
- Increased distance b/w Medial Canthi
- Whitening of Eyelashes
- Loss of eyelashes
a. Bad MGD, Dry Eye, Posterior Blepharitis
b. Sebaceous Gland Carcinoma
4. Eyelashes turn inward (usually secondary to Entropion)
5. Infection of Eyelashes: Due to Phthiriasis Pubis
- Why is the Skin layer of the Eyelid so unique? (what is different from it and the skin of the rest of the body)
- What is the Subcutaneous Layer?
- Orbicularis Layer?
- THINNEST…(no fat…)
- Loose CT b/w outer skin and orbicularis. This layer on UPPER LID contains the LEVATOR APONEUROSIS as it travels to insert on the UPPER TARSAL PLATE
- Location of PALPEBRAL PORTION of ORBICULARIS OCULI
- What happens to the Eyelids if the Orbicularis Oculi is Paralyzed?
- The Lower eyelid will droop away from the Globe –> ECTROPION
Orbicularis Oculi
- Orbital Portion: Function?
- Palpebral Portion: Function
a. What 2 parts does it contain?
- FORCED CLOSURE of EYELIDS (underneath eyebrow…attaches to orbital margins)
- SPONTANEOUS and REFLEX BLINKING
a. Muscle of RIOLAN (Pars Ciliaris) and Muscle of Horner (Pars Lacrimalis)
Orbicularis Oculi
- Muscle of Riolan (Pars Ciliaris)
a. Superficial part of this muscle: What does it do?
b. The most anterior portion of the muscle of Riolan is the GRAY LINE: Purpose? - Muscle of Horner (Pars Lacrimalis)
a. Think “H”…what does “H”orner’s muscle “H”elp do?
b. Where is it found?
- a. Keeps LID MARGIN tightly applied to the GLOBE during eye movements.
b. Found b/w meibomian glands and eyelashes. Divides lid into Ant and Post Portions. It’s a Landmark during SURGERY for lid repairs. - a. “H”elps DRAIN TEARS into Lacrimal Sac.
b. Around the Canaliculi
What are the Layers of the Eyelid? (8)
**Try and Tell the “story of each layer and what makes each layer unique/what their purpose(s) is/are!
- Skin Layer
- Subcutaneous Areolar Layer
- Orbicularis Layer
- Submuscular Areolar Layer
- Orbital Septum
- Posterior Muscular System
- Tarsal Plate
- Palpebral Conjunctiva
Eyelids: Submucsular Areolar Layer
- What is it?
- The upper lid submuscular areolar layer contains what 2 things?
- What 2 things are present in this layer in both upper and lower eyelids?
- another thin loose CT layer b/w Orbicularis and Orbital Septum
- Levator Aponeurosis and Palpebral portion of the main lacrimal gland
- Peripheral and Margin Arcades
Eyelid: Orbital Septum
- What is its PURPOSE?
- What is it?
- Periorbita: What does it cover?
a. Projects Anteriorly to become what?
b. Projects Posteriorly to become what? - Orbital Septum: Continuous with what 2 things of the skull?
a. Where does it attach medially?
b. Does the Lacrimal Sac get protected as well?
c. The Superior Orbital Septum is an Insertion site for what MUSCLE?
- BARRIER to INFECTION and FAT (prevents Orbital Fat Prolapse)
- Dense, Irregular, CT
- Orbital Bones
a. Orbital Septum
b. it fuses w/the DURA of the ON - Periorbita and Periosteum of the Skull
a. Posterior Lacrimal Crest
b. No. It’s anterior to this.
c. Levator Aponeurosis
Eyelid: Posterior Muscular System
- What 3 muscles does this refer to?
- Superior Levator Palpebrae
- Superior Tarsal Muscle (Muller’s)
- Inferior Tarsal Muscle
Eyelid: Posterior Muscular System
- Superior Palpebral Levator Muscle
a. From what bony structure does it ORIGINATE?
b. Purpose? (mm?)
c. Whitnall’s Ligament: Purpose
d. When this muscle hits Whitnall’s Ligament, what it extends to the eyelid as what?
e. How is the SUPERIOR PALPEBRAL FURROW Formed?
f. How is the INFERIOR PALPEBRAL FURROW formed?
g. What do these furrows separate?
- a. Lesser wing of Sphenoid at Orbital Apex
b. Main RETRACTOR of UPPER EYELID (15 mm)
c. Acts as a Fulcrum: Changes muscle course from Ant-Post to Sup-Inf so it can function.
d. a Fan-Shaped Tendon (LEVATOR APONEUROSIS).
e. via Insertion of the Levator Aponeurosis into the skin of the UPPER EYELID.
f. thru INDIRECT Attachment of the IR into the skin of the lower eyelid.
g. Tarsal and Orbital Portions of the Eyelid.
Eyelid: Posterior Muscular System
- Both are SNS innervated
1. Muscle of Muller (INVOLUNTARY)
a. Type of Muscle?
b. Receptors at this muscle?
c. What can block these receptors?
d. Purpose?
e. Called the MINOR RETRACTOR? How much does it widen the palpebral fissure?
f. Originates from what?
- Inferior Levator Muscle: Purpose
a. Originates from?
- a. Smooth
b. a2 receptors
c. Aproclonidine (Iopidine) and Brimonidine (Alphagan)
d. (MAINTAINS EYE BEING OPEN) Widens palpebral fissure
e. 1-3 mm of the upper eyelid lift.
f. on Levator. Extends into Tarsal Plate.
- Minor lower lid retraction
a. Fascial Sheath of IR. Extends into tarsal plate
Eyelids:
- Horner’s: Lack of Sympathetic Inn to Muller and Inf Tarsal muscle: What happens?
- CN 3 Palsy: due to No Parasympathetic inn to LEVATOR: Causes what?
- TED: “stare appearance” due to what?
- Normal Interpalpebral Fissure DISTANCE in ADULTS?
- MILD UPPER LID PTOSIS; REVERSE PTOSIS of LOWER EYELID
- BIG UPPER PTOSIS
- RETRACTION of MUSCLE OF MULLER
- 10-12 mm
Eyelid: Tarsal Plate
- What is it?
a. What does it surround? - Upper and Lower Tarsal Plates combine MEDIALLY and LATERALLY to form what?
a. What does each attach to?
- Dense, Irregular CT…RIGIDITY to EYELIDS
a. Meibomian Glands (Horiz and Vert Collagen Fibrils) - Medial and Lateral PALPEBRAL LIGAMENTS
a. Medial Ligament: Maxillary Bone; Lateral: Whitnall’s Ligament
Eyelid: Palpebral Conjunctiva (inner lining of eyelids that contain 2 layers)
- Epithelial Layer
a. What is it?
b. Contains what CELLS? Found mainly where? - Stroma
a. Type of CT?
b. Made up of 2 layers of what?
- a. Stratified protective layer (into Fornices and onto the Bulbar Conjunctiva)
b. GOBLET CELLS (make Mucin); found mainly in Inferonasal Fornix and Bulbar Conj (most concentrated TEMPORALLY) - a. Loose Vascularized CT
b. Superficial Lymphoid Layer (IMMUNOLOGICALLY ACTIVE: IgA, Macrophages, Mast Cells, PMNs, Eosinophils)
and Deep Fibrous Layer (Connects Conj to internal structures. Has ACCESSORY LACRIMAL GLANDS, Nerves, and BVs of eyelids. Gets continuous w/Dense CT of Tarsal Plate)
Glands of Eyelid and Conjunctiva
- Meibomian Glands
a. How many are there on the upper eyelid?
b. Lower Eyelid? - Glands of Zeis
a. What are they?
b. How many around each eyelash? - Glands of Moll
a. What are they?
b. Purpose? - ALG: What does it stand for?
a. Glands of Krause: Where found and what do they do?
b. Glands of Wolfring: Location: Purpose?
- a. ~25
b. ~20 - a. Modified Sebaceous Glands
b. 2. Lubricate them…prevent them from getting brittle - a. Modified Apocrine Glands (Near LID MARGIN)
b. Dump stuff onto eyelash follicles, Zeis Glands, and Lid Margin - Accessory Lacrimal Glands
a. FORNICES of the CONJ. (Merocrine glands. Secrete same stuff as Lacrimal Gland)
b. Larger…More numerous than the others. Found in TARSAL CONJUNCTIVA.
Tear Summary
- Lipid: 3 types of glands?
- Aqueous (REM)
a. MLG (RE)
b. ALG (M) - Mucous: What glands?
- Meibomian Glands, Zeiss and Moll
- a. Reflexive and Emotional
b. Maintenance - Goblet Cells
- What 2 glands are HOLOCRINE GLANDS? (Whole cell secretion)
- What 2 glands are APOCRINE GLANDS? (Part of Plasma Membrane buds off cell and goes into lumen)
- What glands are MEROCRINE GLANDS? (secretes content via exocytosis…whole cell intact)
- Meibomian Glands and Glands of Zeis
- Glands of Moll and Goblet Cells
- Accessory Lacrimal Glands
Nerves of the Eyelids
- Nerve that innervates the Orbicularis Oculi?
a. Voluntary/Involuntary Motor? - What innervates the Muscle of Muller?
a. Voluntary/Involuntary Motor? - Upper Eyelid
a. V1: (NFL): What branches of each?
b. NFL = ? - Lower Eyelid
a. V2: Innervated by what Branches?
- Zygomatic Branch of FACIAL NERVE
a. Voluntary - SNS
a. Involuntary - a. Lacrimal (Lacrimal Gland); Frontal (Supraorbital and Supratrochlear Nerves); Nasociliary (Infratrochlear Nerve)
b. Nasociliary, Frontal, and Lacrimal Nerves - a. Infraorbital and Zygomatic Nerves
Arterial Supply to Eyelids
- Where are the Palpebral Arcades located in the upper and lower Eyelids?
a. What are they formed by? - The MEDIAL Palpebral Artery is a branch off of what artery?
- What about the LATERAL Palpebral Artery?
- What do the Arcades supply?
- What Palpebral Arcades are located CLOSEST to the Eyelid Margin?
- What arteries supply the FORNICES and Posterior Conjunctiva?
a. What do they connect to (and what do these arteries supply)?
- in Submucosal Areolar Layer
a. Medial and Lateral Palpebral Arteries - Ophthalmic Artery
- Lacrimal Artery
- Deep Eyelid Structures
- MARGINAL Palpebral Arcades
- PALPEBRAL Palpebral Arcades
a. Anterior Ciliary Arteries (Anterior part of the CONJ…Bulbar Conj and Ciliary Body…Reason why Pts w/UVEITIS can experience Circumlimbal Injection and Decreased Aq. Humor Production in that eye)
Veins of the Eyelids
- They parallel the Arteries and drain into what 2 veins?
- Lateral Lymphatics drain into what?
- Medial Lymphatics drain into what?
- Palpebral and Ophthalmic Veins
- Parotid (Preauricular) Lymph Nodes
- Submandibular Lymph Nodes
Eyebrows
- Purpose (2)
- Frontalis: Purpose?
a. Origin?
b. Insertion?
c. Usually used to compensate for what?
d. How do fibers run? - Corrugator: Purpose?
a. How do fibers run?
b. What does it do? (“C”) (Facial expression type?)
c. Origin?
d. Insertion? - “PRO”cerus: Purpose? (PRO Football Player)
a. Origin?
b. Insertion?
c. What does it do?
d. Facial Expression (PRO Football Player…) - Orbicularis Oculi: Purpose?
- Protection and Facial Expression
- Main Elevator of eyebrows and forehead
a. High on Scalp
b. Near Superior Orbital Rim
c. Ptosis
d. Vertically - MEDIAL DEPRESSOR of the eyebrow (Helps protect from sun glare)
a. Oblique
b. Concentration/Sorrow
c. Frontal Bone
d. Skin above Medial Eyebrows - MEDIAL DEPRESSOR of eyebrow
a. Nasal Bone (Nose bridge)
b. Frontalis Muscle b/w Eyebrows on each side of the midline
c. Makes Horizontal FURROWS over the bridge of the nose
d. MENACE/AGGRESSION - Primary LATERAL DEPRESSOR of the Eyebrow
- Lacrimal Gland
a. Location?
b. Divided into Orbital and Palpebral Portion by the tendon of what muscle?
c. Releases Product thru what Secretion type?
d. Innervation type from what nerve?
e. Artery/Vein that supplies it?
f. Dz: ACUTE DACRYOADENITIS: What is it?
- a. Fossa of Frontal Bone
b. Superior Levator Palpebrae Muscle
c. Merocrine Secretion
d. PSNS Inn via LACRIMAL NERVE of CN7 via Pterygopalatine Ganglion
e. Lacrimal Artery/Vein and contains the ONLY Lymph vessels of the orbit (drains to Parotid Lymph Nodes)
f. Infection/Inflammation of Lacrimal Gland: causes Acute Swelling and pain in upper lateral eyelid
- Nasolacrimal Drainage System
a. Lacrimal Puncta: What is responsible for keeping the Puncta open?
b. Length of Canaliculi?
c. What muscle surrounds the canaliculi?
d. Lacrimal Sac: Length? Lined by what cells?
d. 10-12 mm; Double Epithelium (Superficial Columnar and Deep Basal Layers), Microvilli, Goblet Cells.
e. Is the Lacrimal Sac protected by the Orbital septum?f. How does the Lacrimal Sac get divided?
g. Dz: Dacryocystitis: What is it?
h. Nasolacrimal Duct: Lies Adjacent to what? Length? Lined with what? Duct terminates into what?
i. Valve of Hasner: What does it do?
j. NLDO: Adults (2)
k. NLDO: Kids (1)
- a. LACRIMAL PAPILLA
b. 10 mm. 2 mm vertical then 8 mm horizontal
c. Muscle of HORNER (Helps drain TEARS)
d. 10-12 mm; Double Epithelium (Superficial Columnar and Deep Basal Layers), Microvilli, Goblet Cells.
e. NO! the septum is Posterior to the sac.
f. Medial Palpebral Ligament (medial upper and lower tarsal plates)…divides into 2 sections in front of and behind the sac. Muscle of Horner surrounds the Lacrimal Sac, divides it into upper and lower sections
g. Infection of Lacrimal Sac. Usually due to Nasolacrimal Duct Obstruction (Involutional = Old)
h. to MAXILLARY SINUS; 15 mm; Double Epithelium, microvilli, goblet cells; Into Inferior meatus of Nasal Cavity
i. Prevents back flow of nasal fluids into the lacrimal drainage system
j. Stenosis and Sinusitis
k. Valve of Hasner (1/3 born w/o opening)
Orbit
- a. Contents (5)
b. Fat: Intraconal
c. Fat: Extraconal
d. EOMs: Better in every way than Skeletal muscles
e. EOM: SR: Origin? Insertion? Sheath on SR connects to sheaths of what?
f. EOM: LR: Origin? Insertion? What does the Lateral Check Ligament do?
a. Globe, EOMs, ON and smaller nerves, CT, Fat
b. w/in muscle cone of 4 recti muscles. Separates them from ON.
c. Outside muscle cone, b/w EOMs and Orbit Walls
d. Denser Blood supply, Nerve supply; Faster, More fatigue resistant
e. CTR Ant to Sup Orbital Fissure; 7.7 mm from limbus; to that of Superior Levator Palpebrae muscle and CT of Sup Conjunctival Fornix
f. CTR at Spina Recti Lateralis; 6.9 mm from limbus; Anchors LR to Whitnall’s Tubercule on Zygomatic Bone of the orbit.