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1. A 17-year-old girl develops a painful vesicular rash around her left eye. This is followed by blurry vision that occurs only when both eyes are open. She is diagnosed with varicella zoster ophthalmicus. Which of the following ocular motor nerves is most likely to be affected?

A. Long ciliary

B. Superior division of the third

C. Inferior division of the third

D. Fourth (trochlear)

E. Sixth (abducens)

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เฉลยเฉลยข้�อ ข้�อ D.D. Fourth (trochlear) Varicella zoster, previously known as herpes zoster, spreads to the face along the trigeminal nerve. The fourth nerve is presumably involved because it shares its nerve sheath with the ophthalmic division of the trigeminal nerve. The third and sixth nerves may also be involved with varicella zoster, but this occurs much less frequently than involvement of the fourth nerve.


2.2. . . A 5-year-old girl sustains a cut on her face from broken glass. Initially, the A 5-year-old girl sustains a cut on her face from broken glass. Initially, the injury appears superficial except for a small area of deeper penetration just injury appears superficial except for a small area of deeper penetration just above the right eyebrow. Within 4 days, the child complains of periorbital above the right eyebrow. Within 4 days, the child complains of periorbital pain and double vision. The tissues about the eye are erythematous, and the pain and double vision. The tissues about the eye are erythematous, and the eye appears to bulge slightly. The optic disc is sharp, and no afferent eye appears to bulge slightly. The optic disc is sharp, and no afferent pupillary defect is apparent. Visual acuity in the affected eye is preserved. pupillary defect is apparent. Visual acuity in the affected eye is preserved. This child probably has which of the following?This child probably has which of the following?

A.A. Orbital cellulitisOrbital cellulitis

B.B. Cavernous sinus thrombosisCavernous sinus thrombosis

C.C. Transverse sinus thrombosisTransverse sinus thrombosis

D.D. Optic neuritisOptic neuritis

E.E. Diphtheritic polyneuropathyDiphtheritic polyneuropathy

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แบบทดสอบต�ว LicenseEyes .Eyes .

เฉลยเฉลยข้�อ ข้�อ A.A. Orbital cellulitisOrbital cellulitis

The fact that vision is preserved excludes optic neuritis and The fact that vision is preserved excludes optic neuritis and cavernous sinus thrombosis. Optic neuritis will produce pain in the affected cavernous sinus thrombosis. Optic neuritis will produce pain in the affected eye and may be associated with a normal optic disc, but visual acuity should eye and may be associated with a normal optic disc, but visual acuity should be deficient and an afferent pupillary defect should be apparent. Cavernous be deficient and an afferent pupillary defect should be apparent. Cavernous sinus thrombosis usually produces proptosis and pain, but impaired venous sinus thrombosis usually produces proptosis and pain, but impaired venous drainage from the eye should interfere with acuity, and the retina should drainage from the eye should interfere with acuity, and the retina should appear profoundly disturbed. With a diphtheritic polyneuropathy, an appear profoundly disturbed. With a diphtheritic polyneuropathy, an ophthalmoplegia may develop, but this would not be limited to one eye and is ophthalmoplegia may develop, but this would not be limited to one eye and is not usually associated with facial trauma. Transverse sinus thrombosis may not usually associated with facial trauma. Transverse sinus thrombosis may produce cerebrocortical dysfunction or stroke, but ophthalmoplegia would produce cerebrocortical dysfunction or stroke, but ophthalmoplegia would not be a manifestation of this problemnot be a manifestation of this problem


3. A 58-year-old man with type 2 diabetes presents with the acute onset of double vision. Examination reveals a deficit of the third cranial nerve. A third-nerve palsy associated with diabetes mellitus is usually characterized by

which of the following? A. Poor pupillodilation B. Poor pupilloconstriction

C. Sparing of pupillary function

D. Inversion of the affected eye

E. Upward deviation of the affected eye


เฉลยเฉลย

ข้�อ ข้�อ C.C. Sparing of pupillary function The vessel usually obstructed with diabetic third-nerve injury is deep in the third nerve. The superficial fibers to the iris are supplied by a separate set of vessels, and these are usually spared with diabetes mellitus. The affected person may complain of pain in and about the eye with the damaged third nerve.


4. 4. A 23-year-old HIV-infected woman presents with visual loss. After testing, A 23-year-old HIV-infected woman presents with visual loss. After testing, the diagnosis of retinitis caused by cytomegalovirus (CMV) is made. Which the diagnosis of retinitis caused by cytomegalovirus (CMV) is made. Which

of the following should be used to treat this patient?of the following should be used to treat this patient?

A. Cytarabine

B. Vidarabine

C. Ribavirin

D. Interferon

E. Ganciclovir


เฉลยเฉลย ข้�อ ข้�อ E.E. Ganciclovir

All the drugs listed have anti-viral activity with effects on CMV in vitro. Ganciclovir is the only one with demonstrable clinical effects on CMV infection. This drug is a 2-deoxyguanosine analogue and has been used for CMV pneumonia and gastroenteritis as well as chorioretinitis..


55 . . 25-year-old mother develops an illness during 25-year-old mother develops an illness during pregnancy. A diagnosis of cytomegalovirus (CMV) pregnancy. A diagnosis of cytomegalovirus (CMV) infection is made by serology. Prenatal CMV infections infection is made by serology. Prenatal CMV infections

may produce which retinal disturbance?may produce which retinal disturbance?

A. Hemorrhage

B. Cherry red spot

C. Microaneurysms

D. Hypervascularity

E. Chorioretinitis


เฉลยเฉลย ข้�อ ข้�อ E.E. Chorioretinitis Microaneurysms and hypervascularity are Microaneurysms and hypervascularity are typically seen with diabetic retinopathy rather typically seen with diabetic retinopathy rather than developmental disease. Hemorrhages in the than developmental disease. Hemorrhages in the retina would be more typical of hypertensive retina would be more typical of hypertensive encephalopathy or a coagulopathy. Neurologic encephalopathy or a coagulopathy. Neurologic problems that develop in the infant with a problems that develop in the infant with a prenatal CMV infection include retardation, prenatal CMV infection include retardation, microcephaly, seizures, and hearing deficits. The microcephaly, seizures, and hearing deficits. The virus often causes cho-rioretinitis, optic atrophy, virus often causes cho-rioretinitis, optic atrophy, and architectural changes throughout the brainand architectural changes throughout the brain


6 . A newborn child is being examined. During ophthalmologic evaluation, it is noticed that the red reflex is absent. Which of the following could this indicate?

A. Chorioretinitis

B. Retinitis pigmentosa

C. Optic atrophy

D. Congenital cataracts

E. Holoprosencephaly


เฉลยเฉลยข้�อ ข้�อ D.D. Congenital cataracts On shining a light through the pupil of the normal newborn, the normal color of the retina is perceived as an orange-red reflection of the light. Failure to perceive that reflection usually indicates opacification of the pathway of light transmission. Several types of intrauterine infections, including rubella and CMV infection, may produce congenital cataracts and impair light transmission in this way. The presence of a distinctive white reflex usually indicates disease behind the lens, such as a scar from retinopathy of prematurity or a retinoblastoma


7. 7. A 74-year-old man presents with no visual symptoms. On A 74-year-old man presents with no visual symptoms. On funduscopic examination, the cup/disc ratio is greater than 0.5 in funduscopic examination, the cup/disc ratio is greater than 0.5 in the left eye but normal in the right eye. Flame hemorrhages are the left eye but normal in the right eye. Flame hemorrhages are visible at the disc edge. Which of the following is the most likely visible at the disc edge. Which of the following is the most likely

diagnosis?diagnosis?

A. Macular degeneration

B. Cataracts

C. Pterygium

D. Chemosis

E. Glaucoma งานแพทยศาสตรศ�กษา คณะแพทยศาสตร� มศว


เฉลยเฉลย ข้�อ ข้�อ E.E. Glaucoma Glaucoma may occur without visual symptoms, and patients at risk for the disease should be screened carefully. Patients at risk include the elderly, African Americans, those with a family history of glaucoma, and those with a history of hypertension, diabetes mellitus, or myopia. Signs of glaucoma include asymmetry of the cupdisc ratios (even if normal), cup/disc ratio > 0.5, and flame hemorrhages at the edge of the disc. The disc of glaucoma is pale, not hyperemic. Macular degeneration, etiology unknown, is the leading cause of blindness in older persons. Patients complain of a progressive loss of central vision, and funduscopic exam reveals small, yellow-white drusen deposits around the macula and posterior pole of the eye. Cataracts are opacities of the lens; patients often complain of glare and the inability to see well in reduced light (contrast sensitivity). Eye examination reveals a reduced red reflex. A pterygium is an abnormal triangular fold of membrane extending from the conjunctiva to the cornea that occurs because of irritation secondary to sand, dust, or ultraviolet light. Chemosis is conjunctival edema


8 . A 71-year-old woman presents with the chief complaint of distorted central vision. Funduscopic examination reveals the presence of subretinal neovascularization, and there are depigmented areas in the macula. Distinct yellow-white lesions are seen in the posterior pole surrounding the macula. The patient reports wavy lines during Amsler grid testing. Which of the following is the most likely diagnosis?

A. Cataract formation

B. Open-angle glaucoma

C. Macular degeneration

D. Angle-closure glaucoma

E. Narrow-angle glaucoma


เฉลยเฉลย ข้�อ ข้�อ C.C. Macular degeneration

Macular changes include the formation of drusen, subretinal neovascularization, and degenerative changes (depigmentation and atrophy) of the retinal epithelium. Drusen are hyaline nodules or colloid bodies deposited in Bruch's membrane. Amsler grid testing is a method of evaluating the function of the entire macula. The patient looks at a square grid pattern; if he or she sees irregularities in the grid in the form of wavy or fuzzy lines, this indicates macular involvement. Open-angle glaucoma is an insidious form of glaucoma in which the chamber angle remains open. Acute angle-closure glaucoma (also called narrow-angle glaucoma) is an ocular emergency in which the trabeculum suddenly becomes completely occluded by iris tissue. Patients complain of severe eye pain, nausea, and the presence of halos or rainbows around light. The pupil may be fixed and dilated secondary to the abrupt rise in intraocular pressure.


9. 9. A 71-year-old man complains of difficulty in seeing street signs when driving and some difficulty with vision when reading. The patient's vision is 20/100 in his right eye and 20/80 in his left eye. The vision in either eye does not improve with the pinhole test. There is dullness of the red reflex bilaterally; fundi are difficult to visualize with the funduscope. Intraocular pressure is measured to be 15 mmHg in both eyes. Which of the following is the most likely diagnosis?

A.A. CataractCataract B.B. GlaucomaGlaucoma

C.C. Macular degenerationMacular degeneration

D.D. PresbyopiaPresbyopia

E.E. Arcus senilisArcus senilis



เฉลยเฉลยข้�อ ข้�อ A.A. CataractCataract A cataract is opacity of the lens; patients often present complaining of a disturbance in vision. When the lens has a cataract, the red reflex is diminished and it becomes difficult to see the fundus through the opacity. Patients with macular degeneration present with central vision loss, and drusen bodies (yellow-white lesions), retinal atrophy, and neovascularization are often found on funduscopic examination. Presbyopia is a decreased ability to focus on near objects (because of loss of accommodation) that occurs with aging. Glaucoma is an insidious disease, and symptoms occur late in the disease. Patients complain of peripheral vision loss (central vision is spared until late in the disease) and scotomas. Intraocular pressure may be elevated.

10 . Funduscopic examination of a 13-year-old girl shows general and focal arteriolar narrowing. A hemorrhage is observed in the left retina, and sclerosis is present. Her blood pressure is 180/110 mmHg. This girl would be likely to exhibit which of the following symptoms or signs? ?

A. Multiple cranial nerve palsy

B. Hyporeflexia

C. Headache

D. Increased urine output

E. Right ventricular hypertrophy



ข้�อ ข้�อ C. C. Headache Hypertension is usually asymptomatic, but with marked hypertension, children can develop headache, dizziness, visual disturbances, irritability, and nocturnal wakening. Hypertensive encephalopathy can be preceded or accompanied by vomiting, hyperreflexia, ataxia, and focal or generalized seizures. Facial nerve palsy can be the sole manifestation of severe hypertension. Isolated left ventricular hypertrophy, decreased urine output, and abdominal bruits may be possible. When marked fundal changes are present or when there are signs of vascular compromise, emergency treatment of the accompanying hypertension is warranted. Such hypertensive persons require immediate hospitalization for diagnosis and therapy.


1111 . . A 21-year-old woman is seronegative for rubella. You A 21-year-old woman is seronegative for rubella. You caution her against exposure to rubella early in caution her against exposure to rubella early in pregnancy because it can result in an infant with which pregnancy because it can result in an infant with which of the following?of the following?

A. Thrombocytosis

B. Wide-set eyes

C. Duodenal atresia

D. Tetralogy of Fallot

E. Glaucoma


เฉลยเฉลย ข้�อ ข้�อ E.E. Glaucoma When German measles (rubella) occurs during the first 2 When German measles (rubella) occurs during the first 2 months of pregnancy, it has a severe effect on the fetus, months of pregnancy, it has a severe effect on the fetus, including cardiac defects, cataracts, and glaucoma. The including cardiac defects, cataracts, and glaucoma. The most common cardiac defects are patent ductus most common cardiac defects are patent ductus arteriosus, which can be accompanied by peripheral arteriosus, which can be accompanied by peripheral pulmonary artery stenosis, and atrial and ventricular pulmonary artery stenosis, and atrial and ventricular septal defects. A myriad of other complications vary in septal defects. A myriad of other complications vary in incidence with the timing of the infection during incidence with the timing of the infection during pregnancy, including thrombocytopenia, pregnancy, including thrombocytopenia, hepatosplenomegaly, hepatitis, hemolytic anemia, hepatosplenomegaly, hepatitis, hemolytic anemia, microcephaly, and a higher risk of developing insulin-microcephaly, and a higher risk of developing insulin-

dependent diabetes mellitusdependent diabetes mellitus..


12 . A 42-year-old man has horizontal nystagmus in primary gaze and while looking to both the left and the right. The only other examination finding is a slight gait ataxia. The most likely cause of this patient's induced nystagmus is which of the following?

A.A. HysteriaHysteria

B.B. Drug intoxicationDrug intoxication

C. C. EyestrainEyestrain

D. D. MyopiaMyopia

E. E. Hypermetropia


เฉลยเฉลยข้�อ ข้�อ B. B. Drug intoxicationDrug intoxication Alcohol and barbiturates are the drugs that most often cause nystagmus. A variety of hypnotic and antiepileptic drugs are also often implicated because they are widely used by the general population. Although the severity of nystagmus in the two eyes may be unequal, it is invariably worse in the horizontal plane of gaze when the nystagmus is an adverse effect of drug use.


13. A 66-year-old woman presents for her annual eye examination. She has been seeing floaters recently but has no other complaints. Intraocular pressure measurement by Schiotz tonometry is 21 mmHg. Red reflex is visible and normal. Pupils are equal and reactive to light; extraocular muscles are intact. Examination of the fundi reveals the presence of white, indistinct opaque areas in the superficial retina. They occasionally obscure nearby vessels.

There is a positive and normal light reflex. There are no hard exudates, hemorrhages, bony spicule formation, or microaneurysms. The optic cup constitutes 30% of the optic disc, and there is no papilledema. Which of the following is the most likely diagnosis?

A. Glaucoma

B. Early cataract C. Macular degeneration

D. Hypertensive retinopathy

E. Retinitis pigmentosa

เฉลยเฉลยข้�อ ข้�อ D.D. Hypertensive retinopathy Normal intraocular pressure (IOP) is in the range of 10 to 21.5 mmHg. IOP is determined by the outflow of aqueous humor from the eye; the greater the resistance to outflow, the higher the IOP. IOP is important in the diagnosis of glaucoma. A Schiotz tonometer is used to measure IOP. The red reflex represents the light reflected from the retina; it means that all of the light-transmitting media of the eye will be transparent and visible. Cataracts and retinal detachment obscure the presence of a red reflex. The light reflex is emitted from the retinal arterioles; their walls are transparent and the bright light occupies approximately 25% of the diameter of the arterial column of blood. Changes in the light reflex occur with hypertension or with aging (walls thicken and more light is reflected, resembling copper wires). Cotton-wool spots (these are misnamed soft exudates) are white, indistinct, opaque areas of the inner or superficial retina.


They represent microinfarctions and are due to hypertension, diabetes mellitus, infections, collagen vascular diseases, AIDS, and severe anemia. Hard exudates are yellowish, well-demarcated, deep retinal lesions. They are the result of leaky and damaged vessels, not of microinfarcts; they are most commonly due to hypertension and diabetes. Drusen bodies are yellow, deep epithelial pigment deposits located in the macula; they are the earliest sign of macular degeneration. The optic cup is enlarged to >30% of the disc in glaucoma. Retinal hemorrhages are due to leaky and damaged retinal capillaries. Depending on their retinal layer location, they may be blot-and-dot (due to diabetes and hypertension), flame-and-splinter (due to intracranial hemorrhage, papilledema, and glaucoma), or white-centered (Roth spots seen in endocarditis, leukemia, and diabetes). Microaneurysms are outpouchings of the retinal capillaries and are almost always associated with diabetes mellitus. In retinitis pigmentosa, the fundi are covered with a bony spicule formation.

14.14. Routine funduscopic examination of a 52-year-old man reveals small, discrete red dots located in largest numbers in the paracentral region. Such retinal microaneurysms most

often occur with which of the following? A.A. Diabetes mellitusDiabetes mellitus

B.B. SarcoidosisSarcoidosis C.C. Chronic hypertensionChronic hypertension

D.D. Anterior communicating aneurysmsAnterior communicating aneurysms

E.E. ChorioretinitisChorioretinitis


เฉลยเฉลยข้�อ ข้�อ A.A. Diabetes mellitusDiabetes mellitus

These aneurysms appear as small red dots These aneurysms appear as small red dots on the surface of the retina. They may appear as on the surface of the retina. They may appear as one of the first manifestations of diabetes one of the first manifestations of diabetes mellitus and are rarely larger than 90 m across. mellitus and are rarely larger than 90 m across. They may be more obvious in green light. A They may be more obvious in green light. A proliferative retinopathy may occur along with proliferative retinopathy may occur along with these microaneurysms in the patient with these microaneurysms in the patient with diabetes mellitusdiabetes mellitus


15 . A 64-year-old man who has had hypertension for over 30 years is being examined. The most obvious changes seen during retinal exam would

include which of the following? A. Retinal tears

B. Optic atrophy

C. Segmental narrowing of arterioles

D. Drusen

E. Telangiectasias



ข้�อ ข้�อ C.C. Segmental narrowing of arterioles

The vessels apparent on funduscopic examination of the retina are arterioles and venules. In addition to segmental narrowing of arterioles, the retina may exhibit arteriolar straightening and arteriolar-venular compression. The thickened arteriolar wall compresses the venule at the point where they cross, a pattern often referred to as nicking.


16. 16. A 32-year-old woman has an MRI done because of a first seizure. A 32-year-old woman has an MRI done because of a first seizure. No etiology for the seizure is found, but there is the incidental No etiology for the seizure is found, but there is the incidental finding of an aneurysm. The aneurysm is 5 mm and affects the finding of an aneurysm. The aneurysm is 5 mm and affects the posterior communicating artery. It is very close to the third cranial posterior communicating artery. It is very close to the third cranial nerve. Impairment of which of the following is usually the initial nerve. Impairment of which of the following is usually the initial

sign of pressure on the third nerve?sign of pressure on the third nerve?

A. Adduction

B. Abduction

C. Depression

D. Elevation

E. Pupillary constriction



เฉลยเฉลย ข้�อ ข้�อ E.E. Pupillary constriction The pupilloconstrictor fibers of the third nerve lie superficially on the nerve. Lesions compressing the nerve impinge on these fibers before they disturb the ocular motor fibers. The third nerve is not involved in abduction of the globe; this is accomplished by the abducens nerve, which controls the lateral rectus muscle.


1717 . . The newborn pictured was born at home and has puffy, tense eyelids; red The newborn pictured was born at home and has puffy, tense eyelids; red conjunctivae; a copious amount of purulent ocular discharge; and conjunctivae; a copious amount of purulent ocular discharge; and chemosis 2 days after birth. Which of the following is the most likely chemosis 2 days after birth. Which of the following is the most likely diagnosis? diagnosis?

A. Dacryocystitis B. Chemical conjunctivitis C. Pneumococcal ophthalmia D. Chlamydial conjunctivitis

E. Gonococcal ophthalmia


เฉลยเฉลย ข้�อ ข้�อ E.E. Gonococcal ophthalmia The time of onset of symptoms is somewhat helpful in the diagnosis of The time of onset of symptoms is somewhat helpful in the diagnosis of ophthalmia neonatorum. Chemical conjunctivitis is a self-limited condition ophthalmia neonatorum. Chemical conjunctivitis is a self-limited condition that presents within 6 to 12 h of birth as a consequence of silver nitrate or that presents within 6 to 12 h of birth as a consequence of silver nitrate or erythromycin prophylaxis. Silver nitrate is no longer made for ocular erythromycin prophylaxis. Silver nitrate is no longer made for ocular prophylaxis in the United States. Gonococcal conjunctivitis has its onset prophylaxis in the United States. Gonococcal conjunctivitis has its onset within 2 to 5 days after birth and is the most serious of the bacterial within 2 to 5 days after birth and is the most serious of the bacterial infections. Prompt and aggressive topical treatment and systemic antibiotics infections. Prompt and aggressive topical treatment and systemic antibiotics are indicated to prevent serious complications such as corneal ulceration, are indicated to prevent serious complications such as corneal ulceration, perforation, and resulting blindness. Parents should be treated to avoid the perforation, and resulting blindness. Parents should be treated to avoid the risk to the child of reinfection. Silver nitrate is believed by some to be risk to the child of reinfection. Silver nitrate is believed by some to be ineffective prophylaxis against chlamydial conjunctivitis, which occurs 5 to ineffective prophylaxis against chlamydial conjunctivitis, which occurs 5 to 14 days after birth. To avoid the risk of chlamydial pneumonia, treatment with 14 days after birth. To avoid the risk of chlamydial pneumonia, treatment with systemic antibiotics is indicated for the infant as well as both parents in systemic antibiotics is indicated for the infant as well as both parents in cases of chlamydial conjunctivitis.cases of chlamydial conjunctivitis.


18 . . A 25-year-old male is being evaluated. Rhythmic jerk nystagmus is elicited by having the patient look at a rotating drum with stripes

on it. This finding suggests which of the following? A. Drug toxicity

B. Brainstem ischemia

C. Parinaud syndrome

D. No pathologic lesion in the brain

E. Unilateral parietal lobe damage


เฉลยเฉลยข้�อ ข้�อ D.D. No pathologic lesion in the brain

This type of nystagmus is called optokinetic nystagmus. It is a pattern of eye movements that should be elicitable with the normal patient. If the nystagmus is less obvious on rotating the drum in a given direction, the patient may have a parietal lesion responsible for the asymmetric response.


19. A 14-year-old boy presents to your office after being hit in the face by a soccer ball. He complains of left eye pain, and on physical examination you see blood in the anterior chamber. Pupils are equal and reactive to light, and extraocular muscles are intact. Which of the following is the most likely diagnosis?

A. Strabismus

B. Subconjunctival hemorrhage

C. Amblyopia

D. Hyphema

E. Esotropia

เฉลยเฉลยข้�อ ข้�อ D.D. HyphemaA common sequela of blunt trauma to the eye is a hyphema (blood in the anterior chamber). This is caused by rupture of the small blood vessels lying close to the cornea. Strabismus is a misalignment of the eyes. Esotropia is a kind of strabismus in which one eye is deviated inward. Amblyopia (lazy eye) is loss of visual acuity in an otherwise healthy eye. This happens because the healthy eye closes to compensate for the deviating eye to avoid the discomfort of diplopia. This is treatable if discovered early. A subconjunctival hemorrhage (between the conjunctiva and sclera) causes the sudden appearance of a bright red spot.

.


20 . A 48-year-old man presents complaining of bilateral vision loss. He has noticed that his vision has been deteriorating over the last several months. His pupils are equal and reactive to light and accommodation. Extraocular muscle movements and visual field examinations are intact. He has decreased visual acuity as determined by a Snellen chart. Funduscopic examination is normal. Which of the following is the most appropriate next

step in diagnosis?

A. Pinhole test

B. Slit-lamp examination

C. Pseudochromatic plate test

D. Schiotz tonometry

E. Amsler grid test


เฉลยเฉลยข้�อ ข้�อ A.A. Pinhole test

A pinhole test allows only paraxial parallel light rays through and A pinhole test allows only paraxial parallel light rays through and improves visual acuity if refractory errors are present (most improves visual acuity if refractory errors are present (most commonly myopia). The slit-lamp examination is a direct visualization commonly myopia). The slit-lamp examination is a direct visualization of the eye and its components. The pseudochromatic plate test of the eye and its components. The pseudochromatic plate test detects color blindness, and Schiotz tonometry measures intraocular detects color blindness, and Schiotz tonometry measures intraocular pressure. Visual field testing determines if the patient has any blind pressure. Visual field testing determines if the patient has any blind spots. The Amsler grid test screens for macular degeneration. spots. The Amsler grid test screens for macular degeneration. Fluorescein staining is used to detect abrasions of the cornea. A Fluorescein staining is used to detect abrasions of the cornea. A cobalt blue light is used to detect foreign bodies after the fluorescein cobalt blue light is used to detect foreign bodies after the fluorescein is instilled into the affected eye.is instilled into the affected eye.


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