Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Question - Mosaiced.org
Transcript
Head and Neck – Session 5 1 Max. Mark What bones make up the roof of the orbit? Frontal and Sphenoidal (x1) Actual Mark 1 2 Max. Mark What bones make up the floor of the orbit? Maxilla, Zygomatic & Palatine (x1) Actual Mark 1 3 Max. Mark What bones make up the medial side of the orbit? Ethmoid, Maxilla and Lacrimal (x1) Actual Mark 1 4 Max. Mark What bones make up the lateral side of the orbit? Zygomatic and Sphenoid (x1) Actual Mark 1 5 Max. Mark Where do fractures of the orbit usually occur? Usually at bony sutures (x1) Actual Mark 1 6 Max. Mark 3 What areas of the orbit are the most vulnerable and why? What sinuses can be involved? Medial and Lateral walls because they are thin (x1) Medial wall fractures can involve ethmoidal and sphenoidal sinuses (x1) Lateral wall fractures can involve the maxillary sinus (x1) Actual Mark 7 Max. Mark What is a ‘Blow Out’ fracture and describe some signs/symptoms/conditions that a ‘Blow Out’ fracture can cause Fracture that displaces orbital walls and contents (x1) Muscle entrapment (x1) Diplopia (x1) Infection (x1) Actual Mark 4 8 What is enophthalmos? What may happen to reverse it? Max. Mark Depression of the eye/opposite of exophthalmos (x1) Infraorbital bleeding may push the eye back out (x1) Actual Mark 2 9 Max. Mark Describe the contents of the optic canal Optic nerve (x1) Actual Mark 1 10 Max. Mark Describe the contents of the Superior Orbital Fissure from medial to lateral Sympathetic Nerves Ophthalmic Veins Abducens Nerve (CN VI) Inferior branch of Oculomotor Nerve (CN III) Nasociliary Nerve Superior branch of Oculomotor Nerve (CN III) Trochlear Nerve (CN IV) Frontal Nerve Lacrimal Nerve (x1 for every two correct answers. If 9 correct answers, reward self with congratulatory pat on the back) 4 Actual Mark 11 Max. Mark Describe the covering of the Optic Nerve and the clinical relevance of this. What can be found in the centra of the Optic Nerve? Coverings of pia, arachnoid and dura mata of meninges (x1) Continuous with the brain (x1) Infection of the orbit can spread, tracking backwards along the meninges causing meningitis (x1) Central artery and vein (x1) Actual Mark 4 12 Max. Mark Give the name and actions of the 4 recti muscles that move the eyeball Superior – Looks up (x1) Inferior – Looks down (x1) Medial – Looks medial (x1) Lateral – Looks lateral (x1) Actual Mark 4 13 Max. Mark Give the name and actions of the 2 oblique muscles that move the eyeball Superior – Look down (x1) Inferior – Look up (x1) Actual Mark 2 14 Max. Mark What muscle lifts the upper eyelid? Levator Palpebrae Superioris (x1) Actual Mark 1 15 Max. Mark 3 Describe the innervation of the muscles that move the eye and upper eyelid Lateral Rectus – Innervated by the Abducens (CN VI) (x1) Superior Oblique – Innervated by the Trochlear (CN IV) (x1) Everything Else – Innervated by Oculomotor (CN III) (x1) Actual Mark 16 What nerve palsy is this? Explain why it presents like this. Explain how it can be caused Max. Mark Actual Mark Abducens Nerve Palsy (x1) Loss of innervation to the lateral recuts (x1) Unable to move eye laterally (x1) Pupil is fully adducted due to unopposed pull of medial sinus (x1) Caused by fracture involving orbit or cavernous sinus (x1) 5 17 What nerve palsy is this? Explain why it presents like this. Explain how it can be caused Max. Mark Actual Mark Trochlear Nerve Palsy (x1) Loss of innervation to Superior Oblique (x1) Unable to look down when eye is adducted (x1) Caused by orbital fractures or stretching of the nerve during its course around the brainstem (x1) 4 18 What nerve palsy is this? Explain why it presents like this. Explain how it can be caused Max. Mark Actual Mark Oculomotor Nerve Palsy (x1) Superior eyelid droops (x1) – Ptosis, due to loss of innervation to Levator Palpebrae Superioris and unopposed activity or Orbicularis Oris (x1) Pupil is fully dilated and non reactive (x1) – Loss of innervation to Sphincter pupillae and unopposed action of Dilator pupillae(x1) Eye has moved down and out (x1) – Unopposed action of lateral rectus and superior oblique (x1) Caused by fractures involving the cavernous sinus or aneurysms (x1) 8 19 Max. Mark 5 Describe the arterial bloody supply to the Eye and from what vessels they branch. Describe what happens in an obstruction of these arteries. Ophthalmic artery (x1) – Branch of the Internal Carotid Artery (x1) Central Artery of the Retina (x1) – Branch of the Ophthalmic Artery (x1) Obstruction results in instant and total blindness (x1) Actual Mark 20 Max. Mark Describe the venous drainage of the eye and where they drain. Describe what happens in an occlusion of these veins and any other clinical relevance Superior and Inferior Ophthalmic Veins (x1) – Exit via the Superior Orbital Fissure and drain into the cavernous sinus (x1) Actual Mark Central Vein of the Retina - Drains into the cavernous sinus, either directly or via Ophthalmic veins (x1) Occlusion results in slow, painless loss of vision (x1) Infections may also spread by this route from the eye to the brain (x1) 6 21 Max. Mark What is the function of the Eyelids and how is this function performed? Protect cornea and eyeball from injury and keep cornea moist by covering it in Lacrimal Fluid (x1) Eye blinks when cornea becomes dry and eyelids carry a film of fluid over the cornea (x1) Dust and other foreign material is also swept across the medial angle of the eye and removed (x1) Actual Mark 3 22 Max. Mark How are the eyelids strengthened? What do the structures that strengthen the eyelids also contain? Eyelids are strengthened by dense bands of connective tissue known as Tarsal plates (x1) Contain Tarsal glands, which produce secretions that lubricate the edges of the eyelids and prevent them from sticking together when they close (x1) Actual Mark 2 23 Max. Mark 5 Describe the Lacrimal Gland’s function and location Secretes Lacrimal fluid (x1) which contains bacteriocidal lysozyme enzymes, (x1) moistens and lubricates the surface of the conjunctiva and cornea (x1) and provides some nutrients and dissolved oxygen to the cornea (x1) Lies in a fossa on the superolateral part of the orbit (x1) Actual Mark 24 Max. Mark What is the function of the Lacrimal Ducts? Conduct lacrimal fluid from the gland to the conjunctival sac (x1) Actual Mark 1 25 Where do the Lacrimal Canaliculi commence? Max. Mark Commence at the medial angle of the eye where lacrimal fluid is drained from the lacrimal lake to the lacrimal sac (x1) Actual Mark 1 26 Max. Mark What is the function of the Nasolacrimal duct? Conveys lacrimal fluid to the inferior nasal meatus (x1) Actual Mark 1 27 Max. Mark Collectively, what are the Lacrimal Ducts, Canaliculi, Gland and Nasolacrimal Duct known as? The Lacrimal Apparatus (x1) Actual Mark 1 28 Max. Mark Describe what muscles are involved in opening of the eyelids. What is their innervation? What syndrome affects these muscles? Levator Palpebrae Superioris (x1) – Oculomotor Nerve (CN III) (x1) Superior Tarsal Muscles (x1) – Sympathetic Nervous System (x1) Horners Syndrome (x1) Actual Mark 5 29 Max. Mark 3 Describe what muscles are involved in closing of the eyelids. What is their innervation? What palsy affects these muscles? Orbicularis Oris (x1) – Innervated by the Facial Nerve (CN VII) (x1) Bells Palsy (x1) Actual Mark 30 Max. Mark Describe the consequences if the eyelids are prevented from closing properly Cornea becomes dry and left unprotected from dust and other particulate material (x1) Irritation of the eyeball results in excessive tear formation (x1) Actual Mark 2 31 Max. Mark How many layers does the eyeball have? 3 (x1) Actual Mark 1 32 Max. Mark Describe the outermost layer of the eye Outer Protective Layer (x1) which is made up of the Sclera (x1) – Fibrous and provides attachment for Extraocular muscles. Relatively avascular (x1) Cornea (x1) – Transparent and avascular (x1) Actual Mark 5 33 Max. Mark Describe the middle layer of the eye Middle Vascular Layer (x1) which is made up of the Choroid (x1) – Red of eye, continuous anteriorly as the Ciliary Body (x1) Ciliary Body (x1) – Anterior muscle thickening, attaches and focuses the lens (x1) Iris (x1) – Thin diaphragm, aperture is pupil. PSNS contracts the Sphincter pupillae, SNS contracts the Dilator Pupillae (x1) Actual Mark 7 34 Describe the innermost layer of the eye Max. Mark Inner Retina Layer (x1) which is made up of the Optic Part (x1) – Photosensitive, Neural and Pigmented layer (x1) Non-Visual part (x1) – Anterior (x1) 5 Actual Mark 35 Describe what can be found in the Retina of the eye Max. Mark Fundus (x1) – Posterior of the eye Macula (aka macula lutea) (x1) – Contains the fovea centralis Optic Disc (x1) – Convergence of sensory fibres Actual Mark 3 36 What is myopia? Where is the image focused? Max. Mark Short or near-sighted (x1) Image focused in front of the retina (x1) Actual Mark 2 37 Max. Mark What is Hyperopia/Hypermetropia? Where is the image focused? Long or far sighted (x1) Image focused behind the retina (x1) Actual Mark 2 38 Max. Mark What is Presbyopia? Far sighted due to age-related change of the lens (x1) Actual Mark 1 39 Max. Mark 3 What is responsible for the intraocular pressure of the eye? Where is it produced? Where does it drain? Aqueous Humour (x1) Produced by Ciliary Process (x1) Drains into the scleral venous sinus via the trabecular meshwork (x1) Actual Mark 40 Max. Mark What does raised intraocular pressure cause? How is intraocular pressure raised? Glaucoma (x1) Outflow of aqueous humor blocked (x1) Actual Mark 2 41 Max. Mark Name the process by which the eye changes optical power to maintain a clear image or focus on an object as the distance varies Accomodation (x1) Actual Mark 1 42 Max. Mark When an object is near, describe the changes to the lens of the eye Parasympathetic activity in CN III (x1) Sphincter like contraction of Ciliary muscles (x1) Lens more globelike/fatter (x1) Actual Mark 3 43 Max. Mark When an object is far, describe the changes to the lens of the eye No parasympathetic activity to ciliary muscles (x1) Lens becomes stretched and flatter (x1) Actual Mark 2 44 Max. Mark What is the function of Vitreous Humor? Holds the retina in place (x1) Actual Mark 1 45 Max. Mark 2 Describe what is in the retina that helps us see and which type of vision each one gives (I’m sorry this is terrible phrased) Rods – Low light, black and white (x1) Cones – Bright light, colour vision (x1) Actual Mark 46 Max. Mark In regards to the corneal reflex, what nerve do the afferent fibres belong to? Ophthalmic branch of the Trigeminal Nerve (CN V1) (x1) Actual Mark 1 47 Max. Mark In regards to the corneal reflex, what nerve do the efferent fibres belong to? Temporal and zygomatic branches (x1) of the facial nerve (CN VII) (x1) Actual Mark 2 48 Max. Mark In the corneal reflex, what muscle is involved and what action occurs? Contraction of the orbicularis oris (x1) causing eye to blink (x1) Actual Mark 2 49 Max. Mark What are possible consequences of loss of the corneal reflex? Dirt and other particles cause abrasions that cause sudden pain and excessive tears (x1) Injury to the nerves remove this reflex, rendering the cornea vulnerable to foreign particles as they will not be felt (x1) Loss of corneal reflex leads to corneal ulceration (x1) Actual Mark 3 50 Max. Mark What may people with scarred or opaque cornea receive? Corneal transplants (x1) Actual Mark 1 51 Max. Mark 2 What is Mydriasis? What is it more commonly known as? Dilation of the pupil (x1) ‘Blown Pupil’ (x1) Actual Mark 52 Max. Mark What can cause Mydriasis? Under activity of the PSNS leads to lack of innervation to Sphincter Pupillae (x1) Over activity of SNS leads to increased innervation to Dilator Pupillae (x1) Raised intracranial pressure also a possible cause (x1) Actual Mark 3 53 In raised intraocular pressure, how is blindness caused? Max. Mark Compression of the inner layer of the eyeball and central artery of the retina (x1) Actual Mark 1 54 What is Presbyopia? Max. Mark As people age, their lenses become harder and more flattened (x1) This gradually reduces the focusing power of the lens (x1) Actual Mark 2 55 What are Cataracts? Max. Mark Loss of transparency (cloudiness) of the lens from area of opaqueness (x1) Actual Mark 1 56 Max. Mark 2 When is the Intraretinal space present? What happens to it? Space separating layers of the retina in the developing embryo (x1) During the early foetal period, layers fuse and obliterate this space (x1) Actual Mark 57 Max. Mark Describe why retinal detachment can happen and what patients will complain of Pigment cell layer of retina become firmly fixed to the choroid during obliteration of Intraretinal space, however its attachment to the neural layer isn’t firm (x1) Blow to the eye may cause detachment, perhaps days or weeks after the event (x1) Complaints of flashes or specks floating in front of the eye (x1) 58 What is Coloboma? How may it occur? Max. Mark Absence of section of the iris (x1) May result from a birth defect, penetrating or non-penetrating injuries to the eyeball or a surgical iridectomy (x1) Actual Mark Actual Mark 2 59 Max. Mark What is Hyphema? How may it occur? How successful is recovery? Haemorrhage within the anterior chamber of the eye (x1) Blunt force trauma to the eyeball (x1) Anterior chamber tinged red, blood soon accumulates (x1) Recovery is good (x1) Actual Mark 4 60 Max. Mark 3 What is Exophthalmos? If it is bilateral, what has caused it? If it is unilateral, what has caused it? Protrusion of the eye, causing eyelids to part more than normal so that whites of the sclera are visible all around the cornea and iris (x1) Bilateral – Graves’ Disease (x1) Unilateral – Aneurysm or Haematoma (x1) Actual Mark 61 What may cause red ye? What may worsen it? Max. Mark Trauma, infection, allergy or increased eye pressure (x1) Severe coughing spells or recurrent vomiting may cause a patient to have a conjunctival haemorrhage (x1) Actual Mark 2 62 Max. Mark What is a Meibomian Cyst? Blocked Tarsal Gland (x1) Actual Mark 1 63 Max. Mark 1 What is a stye? Infection of sebaceous gland at eyelash base (x1) Actual Mark
