Surg 104--Chapter 26 Flashcards
1
Q
What is the goal of ophthalmic surgery?
A
To restore vision lost as a result of disease, injury, or congenital defect.
2
Q
How many separate bones come together to form the orbit?
A
7
3
Q
What are the bones that form the orbit?
A
- frontal
- lacrimal
- sphenoid
- ethmoid
- maxillary
- zygomatic
- palatine
4
Q
How does the optic nerve enter the posterior orbital cavity?
A
Through the optic foramen.
5
Q
What does the term palpebral refer to?
A
eyelids
6
Q
Located along the lid margin and in the lacrimal carnucle, what secretes a waxy oil that seals the eyelids when they are closed?
A
sebaceous glands
7
Q
What are the two spaces of the anterior cavity of the globe?
A
The anterior chamber and the posterior chamber.
8
Q
What are the six muscles of the eye?
A
- Superior rectus
- Inferior rectus
- Lateral rectus
- Medial rectus
- Superior oblique
- Inferior oblique
9
Q
What is a thin, transparent mucous membrane that lines each eyelid and covers the sclera?
A
conjunctiva
10
Q
What is a clear tissue layer overlying the front of the eyeball?
A
cornea
11
Q
Light enter the eyeball through the _____ and is refracted (bent).
A
cornea
12
Q
The cornea and sclera come together at the _____.
A
limbus
13
Q
During cataract surgery, where is the initial incision made?
A
In the limbus.
14
Q
A thick, white, fibrous tissue that encloses about three fourths of the eyeball and acts as the external supporting layer.
A
sclera
15
Q
Highly vascular, pigmented layer that lies directly behind the sclera. The primary function is to prevent reflection of light within the eyeball.
A
choroid layer
16
Q
An extension of the choroid layer, located at the periphery of the anterior choroid; composed of smooth muscle to which suspensory ligaments are attached.
A
ciliary body
17
Q
Pigmented membrane composed mainly of muscle tissue that surrounds the pupil.
A
iris
18
Q
Innermost layer of the posterior globe; the photo-receptive layer of the eye.
A
retina
19
Q
Receives and transmits images to the brain via the optic nerve.
A
retina
20
Q
Two types of photo-receptive cells:
A
- transmit black and white
2. enable color perception
21
Q
Distinct area of acute vision that lies near the optic nerve.
A
macula
22
Q
What is the center of the macula?
A
fovea centralis
23
Q
A clear, biconcave disk contained in a transparent capsule; lies directly behind the iris in the anterior chamber.
A
lens
24
Q
What ligaments hold the lens in place?
A
zonules
25
The anterior pace of the eye is divided into two separate chambers by the _____ and the _____.
lens and the iris
26
The anterior space in front of the lens and iris is called the _____.
anterior chamber
27
Immediately behind the lens and iris is another space called the _____.
posterior chamber
28
A clear fluid produced by the ciliary epithelium, called the _____, fills the anterior chamber.
aqueous humor
29
The _____ lies between the posterior lens and the retina.
posterior chamber
30
The posterior chamber is filled with _____.
vitreous humor
31
A gel-like substance that fills the posterior chamber and nourishes the inner tissue layers.
vitreous humor
32
Gives shape to the posterior globe and acts as a refractive medium for light.
vitreous humor
33
What produces tears?
lacrimal apparatus
34
The lacrimal ducts extend from the _____ to the _____.
inner canthus to the lacrimal sac
35
The opening of each lacrimal duct is called the _____.
lacrimal punctum
36
Tears are composed of many chemicals including:
- proteins
- mucus
- sodium chloride
- glucose
- enzymes
37
Capable of breaking down the cell membrane of bacteria.
tears
38
The bending of light rays through a transparent medium.
refraction
39
The light rays are refracted as they pass through the _____, _____, _____, and _____, and the rays converge at the focal point.
cornea, aqueous humor, lens, and vitreous
40
A complex process in which the lens continually changes shape to keep the image focused on the fovea.
accommodation
41
Used to examine the anterior chamber of the eye?
slit lamp
42
Used to stain the cornea and highlight irregularities of the epithelial surface.
fluorescein
43
Used to measure intraocular pressure.
tonometer
44
Direct examination of the eyes is performed with an _____.
ophthalmoscope
45
Used extensively in the diagnosis and evaluation of retinal and choroid diseases.
fluorescein angiography
46
Used to measure the density of eye tissues and detect abnormalities.
Ophthalmic ultrasonography
47
Produces and image of the target tissue that shows as a series of spots, the brightness of which corresponds to tissue density.
B-scan ultrasound
48
Depicts tissue density as amplitude on two axes.
A-scan ultrasound
49
During a fluorescein angiography fluorescein dye is injected _____.
intravenously
50
- An opaque lens.
- Aging is the most common cause.
- Other factors may include genetics, trauma, toxins, systemic disease, and certain medications.
cataract
51
- Inversion of the eyelid that occurs in the lower lid.
| - Causes the eyelashes to rub on the cornea.
entropian
52
-Drooping or eversion of the lid.
ectropian
53
- A disease characterized by optic nerve and visual field damage.
- Usually caused by inadequate drainage of aqueous humor.
- Unrelieved pressure damages the optic nerve and may result in progressive blindness.
glaucoma
54
- Degeneration of the rod and cone photo-receptor cells of the retina
- Results in central vision blindness
macular degeneration
55
Most common cause of blindness in people over age 65
Age-related macular degeneration
56
- A separation or tear that allows vitreous to seep between the layers and delaminate them
- Results of trauma of shrinking of the vitreous, which normally occurs with age
retinal detachment
57
- The inability to coordinate the extraocular muscles, which prevents binocular vision
- Caused by weakness or paralysis of the muscles
- May be congenital or acquired
strabismus
58
Anxiety can result in increased _____ and _____.
hemorrhage and intraocular pressure
59
True or False: The ST shares responsibility for errors in lens implants.
True
60
IO implants must be verified _____.
before insertion
61
Lens implants are treated in much the same way as a drug distributed _____.
to the field
62
Ophthalmic surgery is performed with the patient in the _____ with the head stabilized on a circular headrest (doughnut)
supine position
63
Shifting the patient immediately after surgery may result in increased _____ and _____.
IOP and eye injury
64
Antiseptics used for eye prep include _____ (5% or as directed by the surgeon) and _____.
dilute povidone-iodine and hexachlorophene
65
The prep area includes:
- eyelid and margins
- inner and outer canthus
- brows
- face (ending usually at the chin)
66
What is used to irrigate the eye before the skin prep.
BSS or a mild antiseptic of the surgeons shoice
67
Where is the skin prep started?
eyelid
68
True or False: The canthus is considered a contaminated area.
True
69
Most ophthalmic surgery is performed using a anesthetic with monitored sedation.
regional
70
Pediatric patients receive a _____ anesthetic.
general
71
Drugs that dilate the pupil but permit focusing.
mydriatics
72
Drug used for objective examination of the retina, testing of refraction, and easier removal of lenses; may be used alone or with a cycloplegic drug.
Phenylephrine 2.5%, 10% (mydriatics)
73
Drugs that paralyze accomodation and inhibit focusing.
cycloplegics
74
Dilates the pupil, inhibits focusing; anticholinergic, potent, and has a long duration of action (7 to 14 days)
atropine 1% (cycloplegic)
75
Dilates the pupil, added to bottles of balanced salt solution (BSS) for irrigation to maintain pupil dilation during cataract surgery or virectomy
epinephrine (1:1000) (cycloplegic)
76
Potent cholinergic; constricts the pupil, used intraocularly during anterior segment surgery.
Carbachol (Miostat), 0.01%
77
Cholinergic; rapidly constricts the pupil used intraocularly during anterior segment surgery; reconstitute immediately before using
Acetylcholine chloride (Miochol-E), 1%
78
Topical anesthetic: onset 5-20 seconds; duration 10-20 minutes
Tetracaine hydrochloride (Pontocaine), 0.05%
79
Injectible anesthetic: onset 4-6 minutes; duration 40-60 minutes; 120 minutes with epi
Lidocaine (Xylocaine), 1%, 2%, 4%
80
Injectible anesthetic: onset 5-11 minutes; duration 8-12 hours with epi; often used with lidocaine for blocks
Bupivacaine (Marcaine, Sensorcaine), 0.25%, 0.50%, 0.75%
81
Injectible anesthetic: onset 3-5 minutes; duration 2 hours (longer with epi)
Mepivacaine (Carbocaine), 1%, 2%
82
Additives: combined with injectible local anesthetics to prolong anesthesia and reduce bleeding.
Epinephrine
83
Lubricant and support; maintains separation between tissues to protect the endothelium and maintain the anterior chamber ; should be refrigerated; allow 30 minutes to warm to room temp.
Sodium hyaluronate (Healon)
84
Maintains deep chamber for anterior segment procedures, protects epithelium or cornea, and improves visualization; may be used to coat intraocular lens before implantation; should be refrigerated.
Sodium chondroitin-sodium hyaluronate (Viscoat)
85
Used to keep the cornea moist during surgery; also used as an internal irrigant in the anterior or posterior segment.
BSS (Endosol)
86
IV osmotic diuretic; increases the osmolarity of the plasma, causing the osmotic gradient to pull free fluid from the eye into the plasma, thereby reducing the IOP
Mannitol (Osmitrol)
87
Used topically only, never injected; used on cornea to loosen epithelium before debridement and on nasal packing to reduce congection of mucosa
Cocaine
88
IV diagnostic aid: used in fluorescein angiography to diagnose retinal disorders
Fluorescein
89
What are the two types of electrosurgical systems are commonly used in eye surgery?
The single use, battery-powered cautery and the bipolar unit
90
Made of lint-free cellulose or similar material.
eye sponges
91
True or False: The sponge is never used on the cornea.
True
92
The sponge absorbs fluid by _____.
wicking
93
True or False: Only lint-free miscrosurgical wipes are used on instruments.
True
94
In _____, nodal tissue arising from a sebaceous gland is excised from the tarsal plate.
excision of a chalazion
95
An inflammatory, benign growth that originates in a sebaceous gland of the eyelid.
chalazion
96
A chalazion is not _____, but a granuloma develops, which can enlarge and rupture.
infectious
97
An abnormal inversion of the lower eyelid; the goal of surgery is to restore the eyelid to correct anatomical position by resection.
repair of an entropian
98
An inwardly turned eyelid, which causes the eyelashes to rub on the cornea. Occurs primarily in older individuals, caused by weakness and imbalance, almost always affects the lower, rather than the upper eyelids.
entropian
99
Before repair on an entropian, the circulator instills _____ drops into the operative eye.
tetracaine ophthalmic
100
Drooping of the lower eyelid, creates an overflow of tears and exposes the conjunctiva, which becomes dry and irritated.
repair of an ectropian
101
Outwardly turned eyelid, most often associated with with age may also occur congenitally.
ectropian
102
The pterygium membrane is surgically removed to prevent loss of vision.
excision of a pterygium
103
A patch of degenerative elastic tissue that proliferates from the conjunctiva in response to chronic irritation, appears as a white or yellowish vascular mass.
pterygium
104
The creation of a permanent opening in the tear duct for the drainage of tears.
Dacryocystorhinostomy
105
An inflammation on the lacrimal sac, causing pain, redness, and swelling at the site of the medial canthus; appears as a red mass in the septo-orbital area.
dacryosystitis
106
This condition arises from an obstruction or stricture of the nasolacrimal duct.
dacryosystitis
107
Nasal sinus may be packed with gauze impregnated with a topical anesthetic.
dacryosystitis
108
The lacrimal duct is opened and an obstruction is removed.
lacrimal duct probing
109
What is the most common sign of abnormality of the lacrimal system?
constant tearing
110
Performed to correct deviation of the eye caused by strabismus, affected muscles are removed and reattached to the proper location.
muscle resection and muscle recession
111
A condition in which the eyes are unable to focus on point because the muscles lack coordination.
strabismus
112
A portion of the muscle is excised and the severed end in reattached at the original site of insertion.
lateral rectus resection
113
The muscle is detached from its insertion, moved posteriorly, and reattached.
medial rectus recession
114
During muscle resection and recession traction on the muscles can cause a _____, which can result in bradycardia.
vagal response
115
Full-thickness transplantation of a donor cornea to restore vision.
penetrating keratoplasty (corneal transplantation)
116
What are the most common causes of corneal opacification?
- Chemical and thermal burns
- infection
- degenerative disease
117
What are the two types of corneal transplantation?
- lamellar (partial penetrating) keratoplasty
| - penetrating (full-thickness) keratoplasty
118
Anterior chamber is not entered, about one half to two thirds of the cornea is transplanted
partial penetrating
119
The anterior chamber is entered and a full-thickness corneal graft is transplanted.
penetrating technique
120
During a keratoplasty, the donor tissue is placed in _____ or the surgeon's choice or preservative and protected from contamination or injury.
saline
121
Performed to shape the curvature of the cornea and correct a refractory problem; performed with the excimer laser.
LASIK
122
If the anterior-posterior distance of the globe is too short, images that are close are blurred because the focal point is behind the retina; this is called _____.
hyperopia (farsightedness)
123
If the anterior-posterior distance is too long, the focal point lies in front of the retina, resulting in blurred vision of distant objects; this is called _____.
myopia (nearsightedness)
124
Results from an uneven curvature of the refractive medium caused by defects of the cornea, lens, or retina.
astigmatism
125
The fragmentation of tissue by ultrasonic vibration; most common form of cataract removal.
Phacoemulsification (extracapsular cataract extraction)
126
opacity of the lens
cataract
127
what are the most common type of cataract?
age-related
128
The removal of the lens only, leaving the lens capsule intact; most often performed cataract extraction.
extracapsular cataract extraction (ECCE)
129
During prep of ECCE, several drops of _____ are instilled into the eye for antibacterial effect?
Betadine 10%
130
Performed to remove the vitrous from the anterior chamber.
anterior vitrectomy
131
One or more bony sections of the orbital cavity are removed to reduce pressure on the optic nerve.
orbital decompression
132
Complete removal of the eyeball.
enucleation
133
Procedure in which the contents of the eye are removed, but the outer shell of the sclera and the muscle attachments are left intact.
evisceration
134
The removal of the entire eye and orbital contents, including the eyelids, ocular muscles, and orbital fat.
orbital exenteration
