NBEO PART 1 OCULAR ANATOMY ANT SEG EXAM QUESTIONS ANSWERED CORRECTLY LATEST
UPDATE 2026
__________ is an abnormally increased distance between the medial canthi of the eyelids. - Answers
Telecanthus
____________ is whitening of the eyelashes. - Answers Poliosis
____________ is a loss of eyelashes. - Answers Madarosis
_____________ is a turning inward of eyelashes, often secondary to entroprion. - Answers Trichiasis
What makes the skin layer of the eyelid unique compared to the rest of the body? (Choose 2)
A) It is the thickest layer in the body
B) It is the thinnest in the body
C) It contains no protein
D) It contains no fat - Answers B and D
What cranial nerve is responsible for innervating the orbicularis oculi? - Answers CN 7
Which portion of the orbicularis oculi is responsible for forced closure of the eyelids? - Answers
Orbital portion
Which portion of the orbicularis oculi is responsible for spontaneous and reflex blinking? - Answers
Palpebral portion
The Muscle of Riolan is also often referred to as the ______________. - Answers pars ciliaris
What muscle is the most superficial portion of the orbicularis oculi? - Answers Muscle of Riolan
The __________ is the most anterior portion of the muscle of Riolan which divides the lid into
anterior and posterior portions. - Answers gray line
Is the gray line of the muscle of Riolan located on the most anterior or posterior portion of the muscle
of Riolan? - Answers anterior
Which portion of the orbicularis oculi is responsible for keeping the lid margin tightly applied to the
globe during eye movements? - Answers Muscle of Riolan
Paralysis of the orbicularis oculi will cause the lower eyelid to droop away from the globe resulting in
______________. - Answers ectropion
The Muscle of Horner is also referred to as the _________________. - Answers pars lacrimalis
What are the two main muscles that make up the palpebral portion of the orbicularis oculi? - Answers
Muscle of Riolan and Muscle of Horner
The _____________ is a component of the palpebral portion of the orbicularis oculi and encircles
canaliculi in order to help drain tears into the lacrimal sac. - Answers Muscle of Horner
The ____________ acts as a barrier and prevents anterior eyelid infections from entering the orbit. -
Answers orbital septum
True or false? The orbital septum protects the lacrimal sac from infection based on its anatomical
location. - Answers False
The superior orbital septum serves as the insertion site for the _________________. - Answers
levator aponeurosis
What muscle is considered the major retractor of the upper eyelid (~15 mm)? - Answers Superior
palpebral levator muscle
The superior palpebral levator muscle is innervated by which Cranial Nerve? - Answers CN III
____________ ligament on the zygomatic bone serves as fulcrum for the superior palpebral levator
muscle. - Answers Whitnall's ligament
Shortly after reaching Whitnall's ligament, the levator muscle extends into the eyelid as a fan shaped
tendon known as the __________________. - Answers levator aponeurosis
The _____________ palpebral furrow is formed by the insertion of the levator aponeurosis into the
skin of the upper eyelid. - Answers superior
The ___________ palpebral furrow is formed by the indirect attachment of the inferior rectus muscle
into the skin of the lower eyelid. - Answers inferior
The eyelid furrows separate which two portions of the eyelid? (Choose 2)
A) Palpebral
B) Tarsal
C) Orbital
D) Lacrimal - Answers B and C
Is the muscle of muller considered striated or smooth muscle? - Answers smooth muscle
What kind of receptors innervates the Muscle of Muller?
,A) alpha 1
B) alpha 2
C) beta 1
D) beta 2 - Answers B) alpha 2
Is the Muscle of Muller primarily innervated by the sympathetic or parasympathetic ANS? - Answers
sympathetic
The Muscle of Muller provides approximately _______ to _______mm of upper eyelid retraction. -
Answers 1 to 3mm
The Muscle of Muller originates from which eyelid structure? - Answers Levator
True or false? The lower lid provides minor lid retraction and is partially innervated by the
sympathetic system. - Answers True
What ocular condition is known to cause a minor upper lid ptosis due to a lack of sympathetic
innervation to the Muscle of Muller? - Answers Horner's syndrome
What eyelid muscle is primarily affected by Horner's syndrome? - Answers Muscle of Muller
Which of the following ocular conditions can cause an excess retraction of the Muscle of Muller which
leads to a "stare-like" appearance?
A) Horner's syndrome
B) Thyroid eye disease
C) CN III palsy
D) CN VI palsy - Answers B) Thyroid eye disease
The normal interpalpebral fissure of an adult is about ___________ to __________ mm. - Answers 10
to 12mm
_______________ are large sebaceous glands that are located posterior to the eyelash follicles within
the tarsal plate. - Answers Meibomian glands
What does the medial palpebral ligament attach to? - Answers maxillary bone
What does the lateral palpebral ligament attach to? - Answers Whitnall's ligament
Which layer of the palpebral conjunctiva contains goblet cells? - Answers Epithelial layer
Which layer of the palpebral conjunctiva is responsible for producing the mucin layer of the tear film?
- Answers Epithelial layer
Which of the following is NOT equivalent to the stroma layer of the palpebral conjunctiva?
A) Substantia propria
B) Substantia nigra
C) Submucosa - Answers B) Substantia nigra
Which layer of the palpebral conjunctiva is very immunologically active and contains the accessory
lacrimal glands? - Answers Stroma
What are the 2 main layers of the palpebral conjunctiva? - Answers Epithelial and Stroma (substantia
propria)
Which of the following is NOT regarding the substantia propria of the palpebral conjunctiva?
A) It also referred to as the submucosa
B) It primarily houses the goblet cells
C) It contains the accessory lacrimal glands
D) It is a very immunologically active layer - Answers B (Epithelial layer)
What are the two main accessory lacrimal glands? - Answers Krause and Wolfring
Are there more meibomian glands located on the upper lid or lower lid typically? - Answers upper lid
The meibomian glands are primarily responsible for forming which layer of the tear film? - Answers
Lipid layer
Which of the following eyelid glands are considered modified apocrine glands?
A) Glands of Wolfring
B) Glands of Krause
C) Glands of Zeiss
D) Glands of Moll - Answers D) Glands of Moll
Which eyelid gland is considered a modified apocrine gland and primarily empties its contents onto
eyelash follicles, Zeis glands, and the lid margin? - Answers Glands of Moll
Which of the following are considered sebaceous glands? (Choose 2)
A) Glands of Zeis
B) Glands of Moll
C) Glands of Krause
, D) Meibomian glands - Answers A and D
What palpebral conjunctiva structure is considered a type of apocrine gland? - Answers goblet cell
What type of gland are the accessory lacrimal glands considered?
A) Holocrine
B) Apocrine
C) Merocrine - Answers C) Merocrine
Which branch of the facial nerve innervates the orbicular oculi? - Answers zygomatic
What is the main innervation of the superior temporal portion of the eyelid? (Be specific) - Answers
lacrimal branch of CN V1
What is the main innervation of the superior central portion of the eyelid? - Answers Supraorbital
branch of CN V1
What is the main innervation of the superior nasal portion of the eyelid? (Choose 2) - Answers
Supratrochlear and Infratrochlear branch of CN V1
The supraorbital and supratrochlear nerves are terminal branches of which main subdivision of CN
V1? - Answers Frontal
Which region of the inferior eyelid is NOT innervated by CN V2?
A) inferior temporal
B) inferior central
C) inferior nasal - Answers C (Infratrochlear of CN V1)
What is the main innervation of the inferior nasal portion of the eyelid? - Answers Infratrochlear
branch of CN V1
What is the main innervation of the inferior central portion of the eyelid? - Answers Infraorbital nerve
of CN V2
What is the main innervation of the inferior temporal portion of the eyelid? - Answers
Zygomaticofacial nerve of CN V2
A patient presents with a loss of corneal sensation. Which part of their eyelid would you MOST LIKELY
assume to also have decreased sensation?
A) Superior temporal
B) Superior central
C) Inferior temporal
D) Inferior nasal - Answers D) Inferior nasal (Nasociliary of CN V1)
The inferior nasal eyelid is innervated by the infratrochlear nerve which is a terminal branch of which
main subdivision of CN V1? - Answers Nasociliary
Which of the following eyelid nerves is NOT a branch of CN V1?
A) Lacrimal nerve
B) Infraorbital nerve
C) Supraorbital nerve
D) Infratrochlear nerve - Answers B) Infraorbital nerve
Which terminal nerve is known to innervate the medial aspect of the upper AND lower eyelids? -
Answers Infratrochlear nerve
The lateral and medial palpebral arteries are known to supply the deeper eyelid tissue and are
branches of which main artery? - Answers Ophthalmic artery
Which arteries primarily provide circulation to the bulbar conjunctiva and the ciliary body? - Answers
anterior ciliary arteries
The lateral lymphatics of the eyelid drains to what lymph nodes? - Answers Parotid (preauricular)
The medial lymphatics of the eyelid drains to what lymph nodes? - Answers Submandibular
Which condition is MOST likely to present with both preauricular and submandibular
lymphadenopathy?
A) EKC
B) Gonococcal conjunctivitis
C) Parinaud's oculoglandular syndrome
D) Adult inclusion conjunctivitis - Answers C) Parinaud's oculoglandular syndrome
Which of the following is NOT known to cause preauricular lymphadenopathy?
A) EKC
B) PCF
C) Gonococcal conjunctivitis
D) Parinaud's oculoglandular syndrome - Answers B) PCF
UPDATE 2026
__________ is an abnormally increased distance between the medial canthi of the eyelids. - Answers
Telecanthus
____________ is whitening of the eyelashes. - Answers Poliosis
____________ is a loss of eyelashes. - Answers Madarosis
_____________ is a turning inward of eyelashes, often secondary to entroprion. - Answers Trichiasis
What makes the skin layer of the eyelid unique compared to the rest of the body? (Choose 2)
A) It is the thickest layer in the body
B) It is the thinnest in the body
C) It contains no protein
D) It contains no fat - Answers B and D
What cranial nerve is responsible for innervating the orbicularis oculi? - Answers CN 7
Which portion of the orbicularis oculi is responsible for forced closure of the eyelids? - Answers
Orbital portion
Which portion of the orbicularis oculi is responsible for spontaneous and reflex blinking? - Answers
Palpebral portion
The Muscle of Riolan is also often referred to as the ______________. - Answers pars ciliaris
What muscle is the most superficial portion of the orbicularis oculi? - Answers Muscle of Riolan
The __________ is the most anterior portion of the muscle of Riolan which divides the lid into
anterior and posterior portions. - Answers gray line
Is the gray line of the muscle of Riolan located on the most anterior or posterior portion of the muscle
of Riolan? - Answers anterior
Which portion of the orbicularis oculi is responsible for keeping the lid margin tightly applied to the
globe during eye movements? - Answers Muscle of Riolan
Paralysis of the orbicularis oculi will cause the lower eyelid to droop away from the globe resulting in
______________. - Answers ectropion
The Muscle of Horner is also referred to as the _________________. - Answers pars lacrimalis
What are the two main muscles that make up the palpebral portion of the orbicularis oculi? - Answers
Muscle of Riolan and Muscle of Horner
The _____________ is a component of the palpebral portion of the orbicularis oculi and encircles
canaliculi in order to help drain tears into the lacrimal sac. - Answers Muscle of Horner
The ____________ acts as a barrier and prevents anterior eyelid infections from entering the orbit. -
Answers orbital septum
True or false? The orbital septum protects the lacrimal sac from infection based on its anatomical
location. - Answers False
The superior orbital septum serves as the insertion site for the _________________. - Answers
levator aponeurosis
What muscle is considered the major retractor of the upper eyelid (~15 mm)? - Answers Superior
palpebral levator muscle
The superior palpebral levator muscle is innervated by which Cranial Nerve? - Answers CN III
____________ ligament on the zygomatic bone serves as fulcrum for the superior palpebral levator
muscle. - Answers Whitnall's ligament
Shortly after reaching Whitnall's ligament, the levator muscle extends into the eyelid as a fan shaped
tendon known as the __________________. - Answers levator aponeurosis
The _____________ palpebral furrow is formed by the insertion of the levator aponeurosis into the
skin of the upper eyelid. - Answers superior
The ___________ palpebral furrow is formed by the indirect attachment of the inferior rectus muscle
into the skin of the lower eyelid. - Answers inferior
The eyelid furrows separate which two portions of the eyelid? (Choose 2)
A) Palpebral
B) Tarsal
C) Orbital
D) Lacrimal - Answers B and C
Is the muscle of muller considered striated or smooth muscle? - Answers smooth muscle
What kind of receptors innervates the Muscle of Muller?
,A) alpha 1
B) alpha 2
C) beta 1
D) beta 2 - Answers B) alpha 2
Is the Muscle of Muller primarily innervated by the sympathetic or parasympathetic ANS? - Answers
sympathetic
The Muscle of Muller provides approximately _______ to _______mm of upper eyelid retraction. -
Answers 1 to 3mm
The Muscle of Muller originates from which eyelid structure? - Answers Levator
True or false? The lower lid provides minor lid retraction and is partially innervated by the
sympathetic system. - Answers True
What ocular condition is known to cause a minor upper lid ptosis due to a lack of sympathetic
innervation to the Muscle of Muller? - Answers Horner's syndrome
What eyelid muscle is primarily affected by Horner's syndrome? - Answers Muscle of Muller
Which of the following ocular conditions can cause an excess retraction of the Muscle of Muller which
leads to a "stare-like" appearance?
A) Horner's syndrome
B) Thyroid eye disease
C) CN III palsy
D) CN VI palsy - Answers B) Thyroid eye disease
The normal interpalpebral fissure of an adult is about ___________ to __________ mm. - Answers 10
to 12mm
_______________ are large sebaceous glands that are located posterior to the eyelash follicles within
the tarsal plate. - Answers Meibomian glands
What does the medial palpebral ligament attach to? - Answers maxillary bone
What does the lateral palpebral ligament attach to? - Answers Whitnall's ligament
Which layer of the palpebral conjunctiva contains goblet cells? - Answers Epithelial layer
Which layer of the palpebral conjunctiva is responsible for producing the mucin layer of the tear film?
- Answers Epithelial layer
Which of the following is NOT equivalent to the stroma layer of the palpebral conjunctiva?
A) Substantia propria
B) Substantia nigra
C) Submucosa - Answers B) Substantia nigra
Which layer of the palpebral conjunctiva is very immunologically active and contains the accessory
lacrimal glands? - Answers Stroma
What are the 2 main layers of the palpebral conjunctiva? - Answers Epithelial and Stroma (substantia
propria)
Which of the following is NOT regarding the substantia propria of the palpebral conjunctiva?
A) It also referred to as the submucosa
B) It primarily houses the goblet cells
C) It contains the accessory lacrimal glands
D) It is a very immunologically active layer - Answers B (Epithelial layer)
What are the two main accessory lacrimal glands? - Answers Krause and Wolfring
Are there more meibomian glands located on the upper lid or lower lid typically? - Answers upper lid
The meibomian glands are primarily responsible for forming which layer of the tear film? - Answers
Lipid layer
Which of the following eyelid glands are considered modified apocrine glands?
A) Glands of Wolfring
B) Glands of Krause
C) Glands of Zeiss
D) Glands of Moll - Answers D) Glands of Moll
Which eyelid gland is considered a modified apocrine gland and primarily empties its contents onto
eyelash follicles, Zeis glands, and the lid margin? - Answers Glands of Moll
Which of the following are considered sebaceous glands? (Choose 2)
A) Glands of Zeis
B) Glands of Moll
C) Glands of Krause
, D) Meibomian glands - Answers A and D
What palpebral conjunctiva structure is considered a type of apocrine gland? - Answers goblet cell
What type of gland are the accessory lacrimal glands considered?
A) Holocrine
B) Apocrine
C) Merocrine - Answers C) Merocrine
Which branch of the facial nerve innervates the orbicular oculi? - Answers zygomatic
What is the main innervation of the superior temporal portion of the eyelid? (Be specific) - Answers
lacrimal branch of CN V1
What is the main innervation of the superior central portion of the eyelid? - Answers Supraorbital
branch of CN V1
What is the main innervation of the superior nasal portion of the eyelid? (Choose 2) - Answers
Supratrochlear and Infratrochlear branch of CN V1
The supraorbital and supratrochlear nerves are terminal branches of which main subdivision of CN
V1? - Answers Frontal
Which region of the inferior eyelid is NOT innervated by CN V2?
A) inferior temporal
B) inferior central
C) inferior nasal - Answers C (Infratrochlear of CN V1)
What is the main innervation of the inferior nasal portion of the eyelid? - Answers Infratrochlear
branch of CN V1
What is the main innervation of the inferior central portion of the eyelid? - Answers Infraorbital nerve
of CN V2
What is the main innervation of the inferior temporal portion of the eyelid? - Answers
Zygomaticofacial nerve of CN V2
A patient presents with a loss of corneal sensation. Which part of their eyelid would you MOST LIKELY
assume to also have decreased sensation?
A) Superior temporal
B) Superior central
C) Inferior temporal
D) Inferior nasal - Answers D) Inferior nasal (Nasociliary of CN V1)
The inferior nasal eyelid is innervated by the infratrochlear nerve which is a terminal branch of which
main subdivision of CN V1? - Answers Nasociliary
Which of the following eyelid nerves is NOT a branch of CN V1?
A) Lacrimal nerve
B) Infraorbital nerve
C) Supraorbital nerve
D) Infratrochlear nerve - Answers B) Infraorbital nerve
Which terminal nerve is known to innervate the medial aspect of the upper AND lower eyelids? -
Answers Infratrochlear nerve
The lateral and medial palpebral arteries are known to supply the deeper eyelid tissue and are
branches of which main artery? - Answers Ophthalmic artery
Which arteries primarily provide circulation to the bulbar conjunctiva and the ciliary body? - Answers
anterior ciliary arteries
The lateral lymphatics of the eyelid drains to what lymph nodes? - Answers Parotid (preauricular)
The medial lymphatics of the eyelid drains to what lymph nodes? - Answers Submandibular
Which condition is MOST likely to present with both preauricular and submandibular
lymphadenopathy?
A) EKC
B) Gonococcal conjunctivitis
C) Parinaud's oculoglandular syndrome
D) Adult inclusion conjunctivitis - Answers C) Parinaud's oculoglandular syndrome
Which of the following is NOT known to cause preauricular lymphadenopathy?
A) EKC
B) PCF
C) Gonococcal conjunctivitis
D) Parinaud's oculoglandular syndrome - Answers B) PCF
