Anatomy of the Optic Canal
122 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

The optic canal connects the orbit to which structure?

  • Anterior cranial fossa
  • Middle cranial fossa (correct)
  • Posterior cranial fossa
  • Nasal cavity

    • Which of the following nerves is transmitted through the superior orbital fissure? A) Optic nerve B) Oculomotor nerve (III) C) Facial nerve (VII) D) Mandibular nerve (V3)

  • Optic nerve
  • Oculomotor nerve (III) (correct)
  • Facial nerve (VII)
  • Mandibular nerve (V3)

    • Which structure passes through the inferior orbital fissure?

  • Optic nerve
  • Inferior ophthalmic vein (correct)
  • Abducens nerve (VI)
  • Zygomatic branch of the maxillary nerve

    • The nasolacrimal canal connects the orbit to which part of the nasal cavity?

    <p>Inferior nasal meatus</p> Signup and view all the answers

    The inferior orbital fissure connects to all of the following except:

    <p>Middle cranial fossa</p> Signup and view all the answers

    Which of the following structures does NOT pass through the superior orbital fissure?

    <p>Trigeminal nerve (V2)</p> Signup and view all the answers

    The inferior orbital fissure transmits all of the following EXCEPT:

    <p>Superior ophthalmic vein</p> Signup and view all the answers

    Which of the following is true regarding the nasolacrimal canal? A) It allows for the passage of the optic nerve. B) It connects the orbit to the superior nasal meatus. C) It drains tears into the inferior nasal meatus. D) It transmits the ophthalmic artery.

    <p>It drains tears into the inferior nasal meatus.</p> Signup and view all the answers

    The optic canal transmits which of the following structures?

    <p>Optic nerve</p> Signup and view all the answers

    Which opening connects the orbit to the infratemporal fossa?

    <p>Inferior orbital fissure</p> Signup and view all the answers

    The zygomatic branch of the maxillary nerve exits the orbit through which opening?

    <p>Inferior orbital fissure</p> Signup and view all the answers

    The superior ophthalmic vein exits the orbit through which opening?

    <p>Superior orbital fissure</p> Signup and view all the answers

    The abducens nerve (VI) exits the orbit through which structure?

    <p>Superior orbital fissure</p> Signup and view all the answers

    The ophthalmic artery exits the orbit through which opening?

    <p>Optic canal</p> Signup and view all the answers

    Which of the following structures exits the orbit through the inferior orbital fissure?

    <p>Infraorbital nerve</p> Signup and view all the answers

    The nasolacrimal duct drains tears from the orbit and exits into which part of the nasal cavity?

    <p>Inferior nasal meatus</p> Signup and view all the answers

    The Orbicularis oculi muscle is responsible for which of the following? A) Raising the eyelid B) Closing the eyelid C) Moving the eye laterally D) Adjusting pupil size

    <p>Closing the eyelid</p> Signup and view all the answers

    The motor innervation of the Orbicularis oculi muscle is provided by which cranial nerve? A) Trigeminal nerve (CN V) B) Facial nerve (CN VII) C) Oculomotor nerve (CN III) D) Optic nerve (CN II)

    <p>Facial nerve (CN VII)</p> Signup and view all the answers

    Which part of the Orbicularis oculi muscle closes the eyelids gently?

    <p>Palpebral part</p> Signup and view all the answers

    The levator palpebrae superioris muscle is responsible for which of the following? A) Closing the eyelid B) Raising the eyelid C) Blinking D) Secretion of tears

    <p>Raising the eyelid</p> Signup and view all the answers

    The sensory innervation of the eyelid is via which cranial nerve?

    <p>Trigeminal nerve (CN V1)</p> Signup and view all the answers

    What is the name of the membrane behind each eyelid that, when inflamed, causes conjunctivitis?

    <p>Conjunctiva</p> Signup and view all the answers

    The glands in the eyelid that secrete lipid to prevent tear evaporation are called:

    <p>Meibomian glands</p> Signup and view all the answers

    When the Meibomian glands are inflamed, it is referred to as:

    <p>Chalazion/Meibomian cyst</p> Signup and view all the answers

    What condition is caused by the inflammation of the sebaceous or sweat glands in the eyelash? A) Conjunctivitis B) Hordeolum (Stye) C) Meibomian cyst D) Lacrimal duct obstruction

    <p>Hordeolum (Stye)</p> Signup and view all the answers

    The superior tarsus contains which muscle that helps open the eyelid?

    <p>Levator palpebrae superioris</p> Signup and view all the answers

    What is the primary function of the levator palpebrae superioris muscle?

    <p>To raise the eyelid</p> Signup and view all the answers

    The condition chalazion is caused by the inflammation of which type of gland?

    <p>Meibomian gland</p> Signup and view all the answers

    A stye (hordeolum) results from the inflammation of which structure?

    <p>Sebaceous glands or sweat glands in the eyelash follicle</p> Signup and view all the answers

    The superior tarsus is primarily responsible for:

    <p>Raising the eyelid</p> Signup and view all the answers

    The tarsus is a structure found in the eyelid. What is its main function? A) To support the levator palpebrae superioris muscle B) To maintain the shape and structure of the eyelid C) To control the movement of the eye D) To secrete tears and moisture

    <p>To maintain the shape and structure of the eyelid</p> Signup and view all the answers

    The superior tarsus contains which of the following muscles?

    <p>Levator palpebrae superioris</p> Signup and view all the answers

    The inferior tarsus is located in the lower eyelid and contains glands that help produce: A) Lipid secretion to prevent tear evaporation B) Tears to lubricate the eye C) Sweat to cool the eye D) Sebum to nourish the eyelashes

    <p>Lipid secretion to prevent tear evaporation</p> Signup and view all the answers

    Which of the following glands is NOT located in the tarsus?

    <p>Lacrimal glands</p> Signup and view all the answers

    The levator palpebrae superioris muscle, which raises the upper eyelid, is innervated by which nerve?

    <p>Oculomotor nerve (CN III)</p> Signup and view all the answers

    The lacrimal gland is located in which part of the orbit?

    <p>Superior-lateral part of the orbit</p> Signup and view all the answers

    Which of the following structures is involved in the drainage of tears from the lacrimal gland?

    <p>Lacrimal canaliculi</p> Signup and view all the answers

    Tears flow from the lacrimal sac into the nasolacrimal duct and ultimately empty into which part of the nasal cavity?

    <p>Inferior nasal meatus</p> Signup and view all the answers

    The lacrimal puncta are located at the inner corner of the eyelids and serve to collect tears. What is their function? A) To secrete tears B) To drain tears into the lacrimal canaliculi C) To evaporate tears D) To store tears

    <p>To drain tears into the lacrimal canaliculi</p> Signup and view all the answers

    The flow of tears from the lacrimal gland to the nasal cavity follows which order?

    <p>Lacrimal gland → Lacrimal sac → Nasolacrimal duct → Inferior nasal meatus</p> Signup and view all the answers

    The lacrimal canaliculi connect the lacrimal puncta to the:

    <p>Lacrimal sac</p> Signup and view all the answers

    The parasympathetic innervation of the lacrimal gland originates from which nucleus in the pons?

    <p>Superior salivatory nucleus</p> Signup and view all the answers

    The parasympathetic fibers for lacrimal gland secretion travel via the greater petrosal nerve, which is a branch of which cranial nerve?

    <p>Facial nerve (CN VII)</p> Signup and view all the answers

    The greater petrosal nerve carries parasympathetic fibers to the pterygopalatine ganglion, which then sends fibers to the lacrimal gland via which branch of the trigeminal nerve?

    <p>Zygomatic branch of V2</p> Signup and view all the answers

    The sympathetic innervation of the lacrimal gland originates from the superior cervical ganglion and travels via which structure?

    <p>Internal carotid artery</p> Signup and view all the answers

    Which nerve is responsible for the sensory innervation of the lacrimal gland?

    <p>Trigeminal nerve (CN V1)</p> Signup and view all the answers

    In facial nerve palsy, the lacrimal gland function is impaired because the parasympathetic fibers travel through which nerve?

    <p>Facial nerve (CN VII)</p> Signup and view all the answers

    Which of the following is NOT a consequence of facial nerve palsy?

    <p>Paralysis of the diaphragm</p> Signup and view all the answers

    The parasympathetic pathway to the lacrimal gland involves which of the following structures in correct order?

    <p>Superior salivatory nucleus → Greater petrosal nerve → Pterygopalatine ganglion → Zygomatic nerve → Lacrimal nerve</p> Signup and view all the answers

    In facial nerve palsy, which muscle of the eyelids is particularly affected, leading to difficulty in closing the eye?

    <p>Orbicularis oculi</p> Signup and view all the answers

    The trochlear nerve (CN IV) is responsible for the motor innervation of which muscle?

    <p>Superior oblique</p> Signup and view all the answers

    The supratrochlear nerve is a branch of which nerve?

    <p>Ophthalmic nerve (V1)</p> Signup and view all the answers

    The superficial temporal artery is a branch of which larger artery?

    <p>External carotid artery</p> Signup and view all the answers

    Which artery supplies blood to the lacrimal gland?

    <p>Lacrimal artery</p> Signup and view all the answers

    The infra-orbital nerve is a branch of which division of the trigeminal nerve?

    <p>Maxillary (V2)</p> Signup and view all the answers

    The supra-orbital artery is a branch of which larger artery?

    <p>Ophthalmic artery</p> Signup and view all the answers

    Which nerve provides sensory innervation to the skin of the forehead and scalp?

    <p>Supra-orbital nerve</p> Signup and view all the answers

    The angular artery is a continuation of which artery?

    <p>Facial artery</p> Signup and view all the answers

    The lacrimal artery is a branch of which main artery?

    <p>Ophthalmic artery</p> Signup and view all the answers

    Which of the following is the correct order of branches for the ophthalmic nerve (V1)?

    <p>Frontal → Nasociliary → Lacrimal</p> Signup and view all the answers

    The maxillary nerve (V2) gives rise to which of the following branches in the eye region?

    <p>Zygomatic → Infra-orbital</p> Signup and view all the answers

    The ophthalmic artery branches into which of the following vessels in the eye region?

    <p>Lacrimal → Nasociliary → Supra-orbital</p> Signup and view all the answers

    Which of the following is the correct order of branches from the facial nerve (CN VII) that contribute to the eye region?

    <p>Temporal → Zygomatic → Buccal → Marginal mandibular</p> Signup and view all the answers

    The lacrimal nerve (a branch of V1) gives rise to which of the following secondary branches?

    <p>Nasociliary nerve</p> Signup and view all the answers

    The supra-orbital artery is a branch of which artery?

    <p>Ophthalmic artery</p> Signup and view all the answers

    Which of the following arteries is a branch of the internal carotid artery that supplies the eye region?

    <p>Lacrimal artery</p> Signup and view all the answers

    Which nerve branch from the trigeminal nerve (CN V) is responsible for sensory innervation to the lower eyelid and cheek?

    <p>Infra-orbital nerve</p> Signup and view all the answers

    Which nerve supplies the lateral rectus muscle?

    <p>Abducens (VI)</p> Signup and view all the answers

    Which extrinsic eye muscle is innervated by the trochlear nerve (IV)?

    <p>Superior oblique</p> Signup and view all the answers

    All of the following extrinsic eye muscles are supplied by the oculomotor nerve (III) EXCEPT:

    <p>Lateral rectus</p> Signup and view all the answers

    Which cranial nerve innervates most of the extrinsic eye muscles?

    <p>Oculomotor (III)</p> Signup and view all the answers

    A patient presents with strabismus and an inability to abduct their right eye. Which nerve is most likely affected?

    <p>Abducens (VI)</p> Signup and view all the answers

    Which muscle is responsible for depressing the eye while also rotating it medially?

    <p>Superior oblique</p> Signup and view all the answers

    The oculomotor nerve (III) innervates which of the following muscles?

    <p>Inferior oblique and superior rectus</p> Signup and view all the answers

    A lesion in the trochlear nerve (IV) would result in difficulty with which movement?

    <p>Depression of the eye when looking medially</p> Signup and view all the answers

    What condition results from asymmetry in the movement of the extrinsic eye muscles?

    <p>Strabismus (Squint)</p> Signup and view all the answers

    Which extrinsic eye muscle is primarily responsible for elevating the eye?

    <p>Superior rectus</p> Signup and view all the answers

    Which eye muscle is responsible for adduction of the eye?

    <p>Medial rectus</p> Signup and view all the answers

    What is the primary action of the lateral rectus muscle?

    <p>Abduction of the eye</p> Signup and view all the answers

    Which of the following muscles moves the eye down and out?

    <p>Inferior rectus</p> Signup and view all the answers

    The superior rectus muscle moves the eye in which direction?

    <p>Up and in</p> Signup and view all the answers

    Which eye muscle is primarily responsible for elevation when the eye is adducted?

    <p>Inferior oblique</p> Signup and view all the answers

    During clinical examination, which movement is used to isolate the superior and inferior rectus muscles?

    <p>Abduction of the eye</p> Signup and view all the answers

    To test the superior and inferior oblique muscles during a clinical examination, what action is performed first?

    <p>Adduction of the eye</p> Signup and view all the answers

    A patient is unable to look down and out. Which cranial nerve is likely affected?

    <p>Trochlear (IV)</p> Signup and view all the answers

    What is the action of the inferior rectus muscle when the eye is abducted?

    <p>Depresses the eye</p> Signup and view all the answers

    What is the most common cause of strabismus?

    <p>Poor vision in one eye</p> Signup and view all the answers

    Which of the following describes inward deviation of the eye?

    <p>Esotropia</p> Signup and view all the answers

    What is the term used for outward deviation of the eye in strabismus?

    <p>Exotropia</p> Signup and view all the answers

    Which condition refers to downward deviation of the eye in strabismus?

    <p>Hypotropia</p> Signup and view all the answers

    Which of the following is NOT a cause of strabismus?

    <p>Increased intraocular pressure</p> Signup and view all the answers

    A patient has esotropia due to a cranial nerve palsy. Which cranial nerve is most likely affected?

    <p>Abducens nerve (VI)</p> Signup and view all the answers

    What is a possible cause of an eye being physically "stuck" in a particular position?

    <p>Post-traumatic physical restriction</p> Signup and view all the answers

    Which cranial nerve palsy is associated with the inability to abduct the eye?

    <p>Abducens nerve (VI)</p> Signup and view all the answers

    What is the primary cell type responsible for taking the initial visual stimulus from photoreceptors in the retina?

    <p>Bipolar cells</p> Signup and view all the answers

    Which layer of the retina is attached to the choroid?

    <p>Pigment layer</p> Signup and view all the answers

    What occurs at the optic chiasm in terms of visual pathway decussation?

    <p>Partial decussation</p> Signup and view all the answers

    What is the structure in the retina where the optic nerve exits and contains no photoreceptors?

    <p>Optic disc</p> Signup and view all the answers

    Which artery radiates outward from the optic disc?

    <p>Central retinal artery</p> Signup and view all the answers

    Which part of the retina has the highest concentration of cones and greatest photoreceptor sensitivity?

    <p>Fovea centralis</p> Signup and view all the answers

    What separates the neural layer of the retina from the pigment layer in cases of retinal detachment?

    <p>Subretinal space</p> Signup and view all the answers

    Which statement is true about the macula lutea?

    <p>It contains the fovea centralis.</p> Signup and view all the answers

    Which photoreceptor type predominates in the fovea centralis?

    <p>Cones</p> Signup and view all the answers

    Retinal detachment commonly involves which retinal layer?

    <p>Neural layer</p> Signup and view all the answers

    What is the source of the sympathetic innervation to the dilator pupillae muscle?

    <p>Superior cervical ganglion via the internal carotid artery</p> Signup and view all the answers

    Which nucleus is involved in the parasympathetic innervation of the sphincter pupillae muscle?

    <p>Edinger-Westphal nucleus</p> Signup and view all the answers

    What is the function of the ciliary muscle?

    <p>Adjusts the lens for near vision (accommodation)</p> Signup and view all the answers

    Which structure is primarily responsible for producing aqueous humour?

    <p>Cells lining the ciliary body</p> Signup and view all the answers

    What condition results from increased intraocular pressure due to restricted drainage of aqueous humour?

    <p>Glaucoma</p> Signup and view all the answers

    What structure is responsible for draining aqueous humour?

    <p>Trabecular meshwork</p> Signup and view all the answers

    In glaucoma, which structure is damaged due to increased intraocular pressure?

    <p>Optic nerve</p> Signup and view all the answers

    Which type of glaucoma is characterized by partial blockage of the trabecular meshwork?

    <p>Open-angle glaucoma</p> Signup and view all the answers

    What is the primary role of the sphincter pupillae muscle?

    <p>Constricts the pupil in response to light</p> Signup and view all the answers

    Which of the following best describes the role of the dilator pupillae muscle?

    <p>Dilates the pupil in response to dim light or sympathetic activation</p> Signup and view all the answers

    What is the primary consequence of increased intraocular pressure in glaucoma?

    <p>Damage to the optic nerve</p> Signup and view all the answers

    Which of the following can lead to retinal detachment? (Select all that apply)

    <p>All of the above</p> Signup and view all the answers

    Which condition is characterized by leakage from damaged retinal blood vessels due to chronic hyperglycemia?

    <p>Diabetic retinopathy</p> Signup and view all the answers

    Which of the following describes the mechanism of retinal detachment?

    <p>Separation of the neural layer from the pigment layer of the retina</p> Signup and view all the answers

    What is the hallmark of proliferative diabetic retinopathy?

    <p>Formation of new blood vessels on the retina</p> Signup and view all the answers

    What is the first clinical sign of diabetic retinopathy?

    <p>Microaneurysms in retinal vessels</p> Signup and view all the answers

    In glaucoma, blockage of which structure leads to increased intraocular pressure?

    <p>Trabecular meshwork</p> Signup and view all the answers

    What is the treatment for diabetic retinopathy to reduce neovascularization?

    <p>Retinal laser photocoagulation</p> Signup and view all the answers

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser