Anatomy of Skin and Glands

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Questions and Answers

What is the primary function of the meibomian glands?

To provide structural support

To produce keratin

To release sweat

To secrete a lipid-rich fluid (correct)

Which layer of the eyelid contains connective tissue, blood vessels, and nerve fibers?

Orbital septum

Mucocutaneous junction

Epidermis

Dermis (correct)

Where do the glands of Zeis and Moll open?

Into the conjunctival sac

Into the eyebrow hairs

Into the lash follicles (correct)

Into the dermis layer

What is the main retractor muscle of the eyelid?

Levator muscle Signup and view all the answers

What is the role of the orbital septum?

It separates the eyelid and orbit Signup and view all the answers

Which structure is located behind the grey line?

Meibomian glands Signup and view all the answers

What type of glands are the glands of Moll?

Apocrine sweat glands Signup and view all the answers

What happens at the mucocutaneous junction?

Conjunctival mucous membrane merges with keratinized epithelium Signup and view all the answers

What is a characteristic feature of trichotillomania?

Intense impulses to pull out one's hair Signup and view all the answers

Which condition is associated with premature localized whitening of hair?

Poliosis Signup and view all the answers

Which syndrome is characterized by ocular manifestations and can lead to poliosis?

Chronic anterior blepharitis Signup and view all the answers

What is one psychological factor associated with trichotillomania?

Schizophrenia Signup and view all the answers

What condition is characterized by increased distance between the medial canthi?

Telecanthus Signup and view all the answers

What is the normal inner canthal distance (ICD)?

30 mm Signup and view all the answers

Which syndrome is associated with a mutation in the FOXL2 gene?

Blepharophimosis Syndrome Signup and view all the answers

What is the primary treatment approach for Telecanthus?

Surgical correction of medial canthal tendons Signup and view all the answers

Which of the following is NOT a feature of Blepharophimosis-Ptosis-Epicanthus Inversus Syndrome (BPES)?

Prolonged palpebral fissure Signup and view all the answers

What commonly accompanies telecanthus in some cases?

Blepharophimosis Signup and view all the answers

What is a defining characteristic of Turner Syndrome?

Underdeveloped ovaries in females Signup and view all the answers

What is the palpebral fissure length range in Blepharophimosis syndrome?

20-22 mm Signup and view all the answers

Blepharophimosis syndrome is classified as which type of genetic inheritance?

Autosomal dominant Signup and view all the answers

What anatomical structure is specifically elongated in telecanthus?

Medial canthal tendons Signup and view all the answers

Which structure is primarily responsible for closing the eyelids?

Orbicularis oculi Signup and view all the answers

Which type of epicantal fold is most common among children and may disappear within a few years?

Palpebralis folds Signup and view all the answers

Which of the following options describes pseudoesotropia?

Optical illusion of misalignment due to epicanthic folds Signup and view all the answers

What is the approximate vertical distance of the palpebral fissure?

10 mm Signup and view all the answers

Which type of epicantal fold originates in the medial aspect of the upper lids and extends medially?

Tarsalis folds Signup and view all the answers

What is the role of the orbicularis oculi in relation to the lacrimal pump?

Facilitates the closure of the eyelids Signup and view all the answers

Which medical intervention is typically used for correcting epicantal folds?

V-Y or Z-plasty Signup and view all the answers

What condition is associated with inversus folds of the eyelids?

Blepharophimosis Signup and view all the answers

Which cranial nerve innervates the orbicularis oculi muscle?

CN VII Signup and view all the answers

Which type of epicantal fold is most common in Asian ethnicity?

Tarsalis folds Signup and view all the answers

What is the main characteristic of cryptophthalmos?

Absence of the eyelids Signup and view all the answers

What condition is characterized by slanted palpebral apertures?

Coloboma Signup and view all the answers

Which syndrome is associated with both cryptophthalmos and syndactyly?

Fraser Syndrome Signup and view all the answers

What is the likely outcome of congenital upper lid eversion?

Typically resolves spontaneously Signup and view all the answers

What is the primary treatment for ablepharon?

Reconstructive skin grafting Signup and view all the answers

Euryblepharon is associated with which specific eyelid condition?

Horizontal enlargement of the palpebral fissure Signup and view all the answers

Which of these conditions often occurs alongside anophthalmos?

Microblepharon Signup and view all the answers

What condition is indicated by the presence of lagophthalmos and exposure keratopathy?

Euryblepharon Signup and view all the answers

What defines microblepharon?

Small eyelids Signup and view all the answers

What is the most common treatment method for anklyoblepharon filiforme adnatum?

Transection with scissors Signup and view all the answers

Study Notes

Anatomy of the Eyelid

Epidermis: Comprised of a keratin layer providing protection.
Dermis: Contains connective tissue, blood vessels, lymphatics, nerve fibers, fibroblasts, macrophages, and mast cells.
Sebaceous Glands: Located in the caruncle and within eyebrow hairs; produce oils for skin and hair.
Meibomian Glands: Modified sebaceous glands within the tarsal plates, crucial for tear film stability.
Glands of Zeis: Modified sebaceous glands associated with eyelash follicles, secreting a lubricating substance.
Glands of Moll: Modified apocrine sweat glands that open into lash follicles, helping with moisture.
Pilosebaceous Units: Comprises hair follicles along with their sebaceous glands.
Eyelashes (Cilia): Structural features important for eye protection.
Grey Line: Delineates anterior from posterior eyelid layers; meibomian gland orifices lie behind it.
Anterior Layers: Include the muscle of Riolan, gland of Moll, lash follicle, gland of Zeis, and orbicularis oculi muscle.
Posterior Layers: Consist of meibomian gland orifices, mucocutaneous junction, meibomian gland, and conjunctiva.
Mucocutaneous Junction: Where keratinized epithelium of the skin merges with the conjunctival mucous membrane.
Orbital Septum: Multilayer fascia serving as a barrier separating eyelid and orbit.
Levator Muscle: Main eyelid retractor, approximately 15 mm long; inserts into tarsal plate and varies in position among ethnicities.
Muller Muscle: Minor retractor of eyelid, retracting ~3 mm; aids in elevating upper eyelid.
Orbital Fat: Functions as a protective cushion for the eyelids, divided into superior and inferior pads.
Orbicularis Oculi: Main muscle responsible for closing the eyelids; innervated by CN VII; essential for blinking and lacrimal pump function.
Palpebral Fissure Dimensions: Vertical measurement of 10 mm and horizontal measurement of 30 mm.

Congenital Malformations

Epicanthic Folds: Bilateral vertical skin folds extending towards the medial canthi, common in children and absent in adults; normal in some ethnicities.
Pseudoesotropia: Appearance of strabismus due to epicanthic folds.
Epicantal Fold Types:
- Palpebralis: Symmetrical distribution; common in Caucasians.
- Tarsalis: Medially extending folds common in Asians.
- Inversus: Folds starting in the lower lids extending upwards; associated with blepharophimosis.
- Supercilia ris: Folds arising above the brow, extending downward toward the nose.
Telecanthus: Increased distance between medial canthi; may occur with blepharophimosis, Waardenburg syndrome, Mobius syndrome, Teacher Collins syndrome, or Turner syndrome.
Normal Values:
- Inner Canthal Distance (ICD): 30 mm
- Interpupillary Distance (IPD): 61-64 mm
- Outer Canthal Distance (OCD): 85 mm
- Palpebral Fissure Length (PFL): 28-30 mm
Blepharophimosis Syndrome: Autosomal dominant syndrome caused by mutations in the FOXL2 gene; features telecanthus, epicanthus inversus, ptosis, and narrowed palpebral fissures.
Cryptophthalmos: Rare congenital absence of eyelids; may include incomplete forms and features of Fraser Syndrome.
Euryblepharon: Horizontal enlargement of palpebral fissure with ectropion; treatment may involve tarsorrhaphy.
Microblepharon: Exceptionally small eyelids; often linked with anophthalmos.
Ablepharon: Lack of anterior eyelid tissue, necessitating reconstructive surgery; associated with Abelpharon-marostomia Syndrome characterized by multiple anomalies.
Congenital Upper Lid Eversion: Typically bilateral; observed in specific ethnicities; may resolve spontaneously or require surgical intervention.
Ankyloblepharon Filiforme Adnatum: Condition where eyelids are joined by thin tags, usually treatable by surgery.

Skin Disorders and Systemic Diseases

Generalized Alopecia: Loss of hair affecting scalp and eyebrows.
Psoriasis: Chronic skin condition that can influence eyelid skin.
Systemic Diseases:
- Myxoedema,
- Systemic lupus erythematosus,
- Acquired syphilis,
- Lepromatous leprosy.
Trichotillomania: Psychological disorder leading to hair pulling; requires psychological support.
Poliosis: Premature localized whitening of hair; associated conditions include chronic blepharitis, sympathetic ophthalmia, and Vogt-Koyanagi-Harada Syndrome.
Vitiligo and Marfan Syndrome: Skin and connective tissue disorders that may affect the eyelids.

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Description

This quiz covers the anatomy of the skin, focusing on the epidermis, dermis, and various associated glands. Key components such as sebaceous glands and their modifications are explored. Test your knowledge on the structure and function of these critical anatomical features.