3: Anatomy - orbital autonomics

Question 1

Which two bones of the bony orbit is the suspensory ligament attached to?

Answer 1

Lacrimal (medially)

Zygoma (laterally)

Question 2

If the zygoma is fractured, what happens to the suspensory ligament and the eye?

What symptom does this cause?

Answer 2

Suspensory ligament ruptures and eye drops

Diplopia (double vision)

Question 3

Which cranial nerve is response for the sensation of the face?

Answer 3

CN V

(Trigeminal nerve)

Question 4

Which nerves are responsible for sensation of

a) mandible and TMJ
b) maxilla
c) angle of mandible
d) cornea, conjunctiva and bridge of nose

Answer 4

a) CN V3

b) CN V2

c) C2 and C3

d) CN V1

Question 5

What are the names of

a) CN V1
b) CN V2
c) CN V3?

Answer 5

a) Ophthalmic divison of trigeminal nerve

b) Maxillary division of “” ““

c) Mandibular division of “” ““

Question 6

Which cranial nerves are responsible for the

a) sensory
b) motor

parts of the blink reflex?

Answer 6

a) CN V1

b) CN VII

Question 7

Which cranial nerve supplies the orbicularis oculi?

Answer 7

CN VII (Facial nerve)

Question 8

Which part of the orbicularis oculi is responsible for blinking?

Answer 8

Palpebral part

Question 9

Which nerves pass through the

a) supraorbital notch / foramen
b) infraorbital notch

and which cranial nerves do they belong to?

Answer 9

a) Supraorbital nerve from CN V1

b) Infraorbital nerve from CN V2

Question 10

Which fluid nourishes the cornea and washes away debris?

Answer 10

Lacrimal fluid

Question 11

Which structures control

a) pupil diameter
b) lens shape?

Answer 11

a) Iris

b) Ciliary body

Question 12

Where do sympathetic nerves originate?

Answer 12

Autonomic centres in the brain

Question 13

At which levels do sympathetic nerves exit the spinal cord?

Answer 13

T1 - L2

Question 14

Sympathetic nerves exit the spinal cord from __ - __.

Answer 14

T1 - L2

Question 15

After exiting the spinal cord, where do sympathetic nerves go?

Answer 15

Sympathetic chain

Question 16

How do sympathetic nerves reach somatic areas e.g the skin from the sympathetic chain?

Answer 16

Alongside spinal nerves

Question 17

How do sympathetic nerves reach visceral areas i.e the organs?

Answer 17

In splanchnic nerves:

cardiopulmonary splanchnic nerves

abdominopelvic splanchnic nerves

Question 18

How do sympathetic nerves reach

a) organs
b) the skin?

Answer 18

a) Splanchnic nerves

b) Spinal nerves

Question 19

At which spinal level do sympathetic nerves exit the spinal cord to supply the head and neck?

Answer 19

T1

Question 20

The sympathetic nervous system travels in the ___ outflow before reaching the sympathetic chains.

Answer 20

thoracolumbar outflow

T1 to L2

Question 21

Where do sympathetic nerves synapse in the head and neck?

Answer 21

Superior, middle and inferior cervical ganglia

Question 22

Sympathetic nerves for the head and neck exit the spinal cord at __ and travel in the sympathetic chains before synapsing where?

Answer 22

T1

Superior, middle and inferior cervical ganglia

Question 23

After they synapse at the cervical ganglia, which structures do sympathetic nerves travel alongside?

Answer 23

Arteries

In peri-arterial plexuses

Question 24

Which artery transports post-synaptic sympathetic nerves to the orbit?

Answer 24

Ophthalmic artery

Question 25

Which **cranial nerves** do **parasympathetic nerves** come from?

Answer 25

**CN III** (Oculomotor) **CN VII** (Facial) **CN IX** (Glossopharyngeal) **CN X** (Vagus)

Question 26

**CN III, VII, IX** and **X** all transmit **(sympathetic / parasympathetic)** fibres.

Answer 26

**parasympathetic**

Question 27

Apart from cranial nerves, which area transmits **parasympathetic** fibres?

Answer 27

**Sacrum**

Question 28

The **parasympathetic** nervous system has a ___ outflow - why?

Answer 28

**craniosacral** Parasympathetic nerves originate from **CN III, VII, IX** and **X** plus the **sacral spinal nerves** Where as the sympathetic nervous system has a **thoracolumbar outflow** because its nerves come from **T1 - L2 spinal nerves** only

Question 29

The **(sympathetic / parasympathetic)** nervous system supplies the body wall.

Answer 29

**sympathetic**

Question 30

Which **internal organs** are supplied by parasympathetic fibres of a) **CN III** b) **CN VII** c) **CN IX** d) **CN X** e) **Sacral spinal nerves?**

Answer 30

a) **Eye** b) **Submandibular, sublingual and lacrimal glands** c) **Parotid glands** d) **Neck, chest and abdominal organs** up to midgut e) **Hindgut, pelvic and perineal organs**

Question 31

Through which hole in the bony orbit does **CN III** exit?

Answer 31

**Superior orbital fissure**

Question 32

Which extraocular muscles are supplied by **CN III**?

Answer 32

**Medial rectus** **Superior rectus** **Inferior rectus** **Inferior oblique** **Levator palpebrae superioris**

Question 33

**CN III's** (sympathetic / parasympathetic) fibres control muscles of the ___ and synapse at which ganglion?

Answer 33

parasympathetic fibres ## Footnote **eye** **ciliary ganglion**

Question 34

**CN III** splits into **superior** and **inferior** ___ to supply muscles of the eye.

Answer 34

**divisions**

Question 35

Which extraocular muscles are supplied by the a) **superior division** b) **inferior division** of CN III?

Answer 35

**a) Superior rectus, Levator palpebrae superioris** **b) Medial rectus, Inferior rectus, Inferior oblique**

Question 36

Which nerves supply **sympathetic** and **parasympathetic** fibres to **control the diameter of the iris** and the **shape of the lens**?

Answer 36

**Long ciliary nerve** (superior) **Short ciliary nerve** (inferior)

Question 37

The eyes have a lot of involuntary __ in response to different stimuli.

Answer 37

**reflexes**

Question 38

Sympathetic fibres... **(open / close)** the eyes get **(more / less)** light into the eyes focus on **(near / far)** objects produce lacrimal fluid in response to **(debris / emotions)**

Answer 38

**OPEN the eyes** **get MORE light in** **focus on FAR objects** **produce lacrimal fluid in response to EMOTIONS**

Question 39

Parasympathetic fibres... get **(more / less)** light into the eyes focus on **(near / far)** objects

Answer 39

**LESS light into the eyes** **focus on NEAR objects**

Question 40

Which muscle **opens** the upper eyelid? Which cranial nerve supplies it? Which type of autonomic fibres cause it to open in a reflex?

Answer 40

**Levator palpebrae superioris** **CN III** **Sympathetic**

Question 41

What structure is the levator palpebrae superioris attached to?

Answer 41

**Superior tarsus**

Question 42

Which autonomic fibres **dilate** the pupils?

Answer 42

**Sympathetic fibres**

Question 43

A **non-physiologically** **dilated** **pupil** is called a ___ pupil.

Answer 43

**mydriatic**

Question 44

Which muscle **dilates** the pupil?

Answer 44

**Dilator pupillae**

Question 45

Which autonomic fibres **constrict** the pupils?

Answer 45

**Parasympathetic fibres**

Question 46

Which muscle **constricts** the pupils?

Answer 46

**Sphincter pupillae**

Question 47

In which light conditions does the pupil a) constrict b) dilate?

Answer 47

**a) Bright light** **b) Low light**

Question 48

A non-physiologically **constricted** pupil is called a ___ pupil.

Answer 48

**miotic pupil**

Question 49

**Mydriatic pupils** are abnormally \_\_\_. **Miotic pupils** are abnormally \_\_\_.

Answer 49

**dilated** **constricted**

Question 50

Which syndrome, caused by reduced sympathetic impulses to the head and neck, causes **miotic pupils**?

Answer 50

**Horner's syndrome**

Question 51

Which drugs cause **miosis**?

Answer 51

**Opiates**

Question 52

A **fixed-dilated** pupil is a sign of problems with which cranial nerve?

Answer 52

**CN III**

Question 53

What is the **pupillary light reflex**?

Answer 53

**Pupils BILATERALLY constrict into response to bright light**

Question 54

Is the pupillary light reflex **unilateral** or **bilateral**?

Answer 54

**Bilateral**

Question 55

Which nerves control the a) sensory b) motor parts of the pupillary light reflex?

Answer 55

**a) CN II** **b) CN III**

Question 56

The **pupillary light reflex** is a _ neurone chain.

Answer 56

**4 neurone chain**

Question 57

Which ganglia do impulses from the optic nerve travel through?

Answer 57

**Retinal ganglia**

Question 58

Which part of the midbrain do impulses **synapse** at in the pupillary light reflex?

Answer 58

**Pretectal ganglia**

Question 59

Which specific part of the **pretectal nucleus** do nerve impulses synapse at in the pupillary light reflex?

Answer 59

**Edinger-Westphal nucleus**

Question 60

Which cranial nerve has parasympathetic fibres in the Edinger-Westphal nucleus?

Answer 60

**CN III** Oculomotor nerve

Question 61

After synapsing at the EW nucleus, parasympathetic nerves then synapse in ___ ganglia before travelling along which nerve to the sphincter pupillae muscles?

Answer 61

**ciliary** **short ciliary nerves**

Question 62

Which structures are responsible for the shape of the **lens**?

Answer 62

**Suspensory ligament** **Ciliary muscles**

Question 63

What do ciliary muscles do to **focus the lens** on near objects? Which autonomic nerves control this?

Answer 63

**Contract** **Parasympathetics**

Question 64

What do ciliary muscles do to focus the lens on **far objects**? Which autonomic nerves control this?

Answer 64

**Relax** **Sympathetic**

Question 65

When the ciliary muscles **contract**, the lens **(flattens / becomes spherical)** to focus on **(near / far)** objects.

Answer 65

**contraction** **becomes spherical** **near objects**

Question 66

When the ciliary muscles **relax**, the lens **(flattens / becomes spherical)** to focus on **(near / far)** objects.

Answer 66

**relaxation** **flattens** **far objects**

Question 67

Which cranial nerve controls the **ciliary** **muscles**?

Answer 67

**CN III** Oculomotor nerve

Question 68

What is the **accomodation reflex**?

Answer 68

**Focusing of eyes on object coming towards you in the midline**

Question 69

In the **accommodation reflex**, CN III controls **three** different actions. What are they?

Answer 69

**1. Bilateral pupillary constriction** by sphincter papillae muscles **2. Adduction of eyes towards midline** by medial rectus muscles **3.** **Focusing of lens on near object** by ciliary muscles

Question 70

Which fluid **nourishes the cornea?**

Answer 70

**Lacrimal fluid**

Question 71

Lacrimal fluid is also known as what?

Answer 71

**Tears**

Question 72

Which cranial nerves control the a) sensory b) motor components of the **reflex production of lacrimal fluid**?

Answer 72

**a) CN V1** - ophthalmic division of trigeminal nerve **b)** **CN VII** - facial nerve (which supplies lacrimal glands)

Question 73

With regard to the eyes and face, what are the functions of **CN VII?**

Answer 73

**Glands:** lacrimal, submandibular, sublingual **Muscles:** orbicularis oculi (and other muscles of facial expression)

Question 74

What are the symptoms of **Horner's syndrome**?

Answer 74

**Miosis** (constricted pupil unilaterally) **Ptosis** (droopy eyelid ipsilaterally) **Reduced sweating** (anhydrosis) **Increased warmth and redness**