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Question 1
Incorrect
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You evaluate the pupillary light reflex in a patient with a cranial nerve impairment. When the light is directed into the left eye, there is no alteration in pupil size in either the left or right eye. However, when the light is directed into the right eye, both the left and right pupils constrict.
What is the location of the lesion in this scenario?Your Answer: Left oculomotor nerve
Correct Answer: Left optic nerve
Explanation:The pupillary light reflex is a reflex that regulates the size of the pupil in response to the intensity of light that reaches the retina. It consists of two separate pathways, the afferent pathway and the efferent pathway.
The afferent pathway begins with light entering the pupil and stimulating the retinal ganglion cells in the retina. These cells then transmit the light signal to the optic nerve. At the optic chiasm, the nasal retinal fibers cross to the opposite optic tract, while the temporal retinal fibers remain in the same optic tract. The fibers from the optic tracts then project and synapse in the pretectal nuclei in the dorsal midbrain. From there, the pretectal nuclei send fibers to the ipsilateral Edinger-Westphal nucleus via the posterior commissure.
On the other hand, the efferent pathway starts with the Edinger-Westphal nucleus projecting preganglionic parasympathetic fibers. These fibers exit the midbrain and travel along the oculomotor nerve. They then synapse on post-ganglionic parasympathetic fibers in the ciliary ganglion. The post-ganglionic fibers, known as the short ciliary nerves, innervate the sphincter muscle of the pupils, causing them to constrict.
The result of these pathways is that when light is shone in one eye, both the direct pupillary light reflex (ipsilateral eye) and the consensual pupillary light reflex (contralateral eye) occur.
Lesions affecting the pupillary light reflex can be identified by comparing the direct and consensual reactions to light in both eyes. If the optic nerve of the first eye is damaged, both the direct and consensual reflexes in the second eye will be lost. However, when light is shone into the second eye, the pupil of the first eye will still constrict. If the optic nerve of the second eye is damaged, the second eye will constrict consensually when light is shone into the unaffected first eye. If the oculomotor nerve of the first eye is damaged, the first eye will have no direct light reflex, but the second eye will still constrict consensually. Finally, if the oculomotor nerve of the second eye is damaged, there will be no consensual constriction of the second eye when light is shone into the unaffected first eye.
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This question is part of the following fields:
- Ophthalmology
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Question 2
Correct
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A 42-year-old male patient comes in with a pituitary tumor that has resulted in a visual field defect.
What type of visual field defect is he most likely experiencing?Your Answer: Bitemporal hemianopia
Explanation:The optic chiasm is situated just below the hypothalamus and is in close proximity to the pituitary gland. When the pituitary gland enlarges, it can impact the functioning of the optic nerve at this location. Specifically, the fibres from the nasal half of the retina cross over at the optic chiasm to form the optic tracts. Compression at the optic chiasm primarily affects these fibres, resulting in a visual defect that affects peripheral vision in both eyes, known as bitemporal hemianopia. There are several causes of optic chiasm lesions, with the most common being a pituitary tumor. Other causes include craniopharyngioma, meningioma, optic glioma, and internal carotid artery aneurysm. The diagram below provides a summary of the different visual field defects that can occur at various points in the visual pathway.
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This question is part of the following fields:
- Ophthalmology
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Question 3
Correct
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A 42-year-old woman comes in with a suddenly painful right eye and sensitivity to light. She describes her eye as feeling gritty and it is noticeably watery. The patient has been experiencing a mild cold for the past few days. You administer fluorescein drops to her eye, which reveal the presence of a dendritic ulcer.
What is the most suitable treatment for this patient?Your Answer: Acyclovir ointment
Explanation:There are two types of infectious agents that can lead to the development of a dendritic ulcer. The majority of cases (80%) are caused by the herpes simplex virus (type I), while the remaining cases (20%) are caused by the herpes zoster virus. To effectively treat this condition, the patient should follow a specific treatment plan. This includes applying acyclovir ointment topically five times a day for a duration of 10 days. Additionally, prednisolone 0.5% drops should be used 2-4 times daily. It is also recommended to take oral high dose vitamin C, as it has been shown to reduce the healing time of dendritic ulcers.
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This question is part of the following fields:
- Ophthalmology
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Question 4
Incorrect
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A 12-year-old boy presents with double vision. He is holding his head tilted to the left-hand side. On examination of his eye movements, you note that both eyes can look normally to the right, but on looking to the left, his left eye cannot turn outwards past the midline. The right eye is unaffected when looking to the left.
What is the SINGLE most likely nerve to be involved in this case?Your Answer: Left oculomotor nerve
Correct Answer: Right abducens nerve
Explanation:This patient is experiencing a condition called right-sided abducens nerve palsy, which means that their sixth cranial nerve is paralyzed. As a result, the lateral rectus muscle, which is responsible for moving the eye outward, is also paralyzed. This means that the patient’s right eye is unable to turn outward. This can lead to a condition called convergent strabismus, where the eyes are not aligned properly, and diplopia, which is double vision. To compensate for the double vision, patients often tilt their head towards the side of the paralyzed muscle.
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This question is part of the following fields:
- Ophthalmology
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Question 5
Incorrect
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A 60-year-old man comes in with decreased visual acuity and 'floaters' in his right eye. Upon conducting fundoscopy, you observe a sheet of sensory retina bulging towards the center of the eye.
What is the MOST LIKELY diagnosis?Your Answer: Age-related macular degeneration
Correct Answer: Retinal detachment
Explanation:Retinal detachment is a condition where the retina separates from the retinal pigment epithelium, resulting in a fluid-filled space between them. This case presents a classic description of retinal detachment. Several risk factors increase the likelihood of developing this condition, including myopia, being male, having a family history of retinal detachment, previous episodes of retinal detachment, blunt ocular trauma, previous cataract surgery, diabetes mellitus (especially if proliferative retinopathy is present), glaucoma, and cataracts.
The clinical features commonly associated with retinal detachment include flashes of light, particularly at the edges of vision (known as photopsia), a dense shadow in the peripheral vision that spreads towards the center, a sensation of a curtain drawing across the eye, and central visual loss. Fundoscopy, a procedure to examine the back of the eye, reveals a sheet of sensory retina billowing towards the center of the eye. Additionally, a positive Amsler grid test, where straight lines appear curved or wavy, may indicate retinal detachment.
Other possible causes of floaters include posterior vitreous detachment, retinal tears, vitreous hemorrhage, and migraine with aura. However, in this case, the retinal appearance described is consistent with retinal detachment.
It is crucial to arrange an urgent same-day ophthalmology referral for this patient. Fortunately, approximately 90% of retinal detachments can be successfully repaired with one operation, and an additional 6% can be salvaged with subsequent procedures. If the retina remains fixed six months after surgery, the likelihood of it becoming detached again is low.
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This question is part of the following fields:
- Ophthalmology
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Question 6
Incorrect
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A 60-year-old man comes in with decreased vision and floaters in his right eye. Upon fundoscopy, you observe a section of sensory retina protruding towards the center of the eye. A diagnosis of retinal detachment is confirmed.
Which of the following statements about retinal detachment is correct?Your Answer:
Correct Answer: A retina which remains fixed at six months post-surgical repair is unlikely to become detached again
Explanation:Retinal detachment is a condition where the retina separates from the retinal pigment epithelium, resulting in a fluid-filled space between them. This case presents a classic description of retinal detachment. Several risk factors increase the likelihood of developing this condition, including myopia, being male, having a family history of retinal detachment, previous episodes of retinal detachment, blunt ocular trauma, previous cataract surgery, diabetes mellitus (especially if proliferative retinopathy is present), glaucoma, and cataracts.
The clinical features commonly associated with retinal detachment include flashes of light, particularly at the edges of vision (known as photopsia), a dense shadow in the peripheral vision that spreads towards the center, a sensation of a curtain drawing across the eye, and central visual loss. Fundoscopy, a procedure to examine the back of the eye, reveals a sheet of sensory retina billowing towards the center of the eye. Additionally, a positive Amsler grid test, where straight lines appear curved or wavy, may indicate retinal detachment.
Other possible causes of floaters include posterior vitreous detachment, retinal tears, vitreous hemorrhage, and migraine with aura. However, in this case, the retinal appearance described is consistent with retinal detachment.
It is crucial to arrange an urgent same-day ophthalmology referral for this patient. Fortunately, approximately 90% of retinal detachments can be successfully repaired with one operation, and an additional 6% can be salvaged with subsequent procedures. If the retina remains fixed six months after surgery, the likelihood of it becoming detached again is low.
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This question is part of the following fields:
- Ophthalmology
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Question 7
Incorrect
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A 32-year-old woman comes in with a painful, red left eye. She is also experiencing bilateral knee discomfort. Her medical history includes frequent and recurring mouth and genital ulcers. Upon examination of her eye, there is circumlimbal redness and a hypopyon is visible. Her left pupil has a poor reaction to light.
What is the SINGLE most probable diagnosis?Your Answer:
Correct Answer: Behçet’s syndrome
Explanation:Behçet’s syndrome is a systemic vasculitis that is mediated by the immune system. It is characterized by various symptoms, including polyarthritis, which primarily affects large joints. Additionally, patients with Behçet’s syndrome often experience recurrent oral and genital ulcers. Ocular disease is also common, with manifestations such as uveitis, hypopyon, and iridocyclitis. Furthermore, neurological involvement can occur, leading to demyelination, parkinsonism, and dementia. In this particular case, the patient’s eye examination reveals features consistent with anterior uveitis and the presence of a hypopyon. While several conditions can cause anterior uveitis, the patient’s history of joint pain in large joints and recurrent oral and genital ulcers strongly suggest Behçet’s syndrome as the most likely diagnosis.
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This question is part of the following fields:
- Ophthalmology
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Question 8
Incorrect
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A 42-year-old woman presents with right eye pain and sensitivity to light. She reports that the eye pain worsens when she reads or uses her computer. Her eye is excessively watery. During the examination, her right pupil is constricted, and there is noticeable redness around the iris. Her visual acuity is measured and found to be 6/6. She has a history of ankylosing spondylitis and takes a non-steroidal anti-inflammatory medication.
What is the MOST LIKELY diagnosis for this patient?Your Answer:
Correct Answer: Anterior uveitis
Explanation:Anterior uveitis refers to the inflammation of the middle layer of the eye, which includes the iris and the ciliary body. If left untreated, it can lead to permanent damage and vision loss due to the development of conditions like glaucoma, cataract, or retinal edema.
There are various causes of anterior uveitis, including eye trauma from being hit or having a foreign object in the eye. It can also be associated with inflammatory disorders such as ankylosing spondylitis.
The clinical features of anterior uveitis are characterized by a red and sore eye, accompanied by pain that worsens when the ciliary muscles contract. Other symptoms include watering of the eye, blurred vision, sensitivity to light (photophobia), and a constricted or distorted pupil. The visual acuity may be normal or reduced.
Overall, anterior uveitis is a condition that requires prompt attention and treatment to prevent further complications and preserve vision.
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This question is part of the following fields:
- Ophthalmology
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Question 9
Incorrect
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A 65-year-old man comes in with a chief complaint of sudden vision loss in his right eye over the past couple of hours. During fundoscopic examination, you observe engorgement of the retinal veins and notice multiple flame-shaped hemorrhages and cotton wool spots scattered throughout the entire retina.
What is the SINGLE most probable diagnosis?Your Answer:
Correct Answer: Central retinal vein occlusion
Explanation:Central retinal vein occlusion (CRVO) is a condition that usually leads to painless, one-sided vision loss. When examining the retina, it may appear similar to a ‘pizza thrown against a wall’, with swollen retinal veins, swelling of the optic disc, numerous flame-shaped hemorrhages, and cotton wool spots. Hypertension is present in about 65% of CRVO cases and is more common in individuals aged 65 and above.
On the other hand, branch retinal vein occlusion (BRVO) typically affects only one section of the retina, resulting in visual field deficits in that specific quadrant rather than complete vision loss.
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This question is part of the following fields:
- Ophthalmology
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Question 10
Incorrect
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A 45-year-old woman comes in with a painful red eye accompanied by sensitivity to light, excessive tearing, and reduced vision. The on-call ophthalmology team is consulted, and they diagnose her with anterior uveitis.
Which of the following is the SINGLE LEAST probable underlying cause?Your Answer:
Correct Answer: Lymphoma
Explanation:Anterior uveitis refers to the inflammation of the iris and is characterized by a painful and red eye. It is often accompanied by symptoms such as sensitivity to light, excessive tearing, and a decrease in visual clarity. In less than 10% of cases, the inflammation may extend to the posterior chamber. The condition can also lead to the formation of adhesions between the iris and the lens or cornea, resulting in an irregularly shaped pupil known as synechia. In severe cases, pus may accumulate in the front part of the eye, specifically the anterior chamber, causing a condition called hypopyon.
There are various factors that can cause anterior uveitis, including idiopathic cases where no specific cause can be identified. Other causes include trauma, chronic joint diseases like spondyloarthropathies and juvenile chronic arthritis, ankylosing spondylitis, inflammatory bowel disease, psoriasis, sarcoidosis, and infections such as Lyme disease, tuberculosis, leptospirosis, herpes simplex virus (HSV), and varicella-zoster virus (VZV). It is worth noting that approximately 50% of patients with anterior uveitis have a strong association with the HLA-B27 genotype.
Complications that can arise from uveitis include the development of cataracts, glaucoma, band keratopathy (a condition where calcium deposits form on the cornea), and even blindness.
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This question is part of the following fields:
- Ophthalmology
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Question 11
Incorrect
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A 70-year-old man experiences a sudden loss of vision in his left eye. He is later diagnosed with central retinal artery occlusion (CRAO).
Which ONE statement about this condition is accurate?Your Answer:
Correct Answer: The pupil on the affected side is usually poorly reactive to light with a normal consensual light reaction
Explanation:Central retinal artery occlusion (CRAO) is characterized by sudden and painless loss of vision in the affected eye. It can occur due to emboli from atheromatous carotid arteries, thrombosis caused by arteriosclerosis or hypertension, or vasospasm resulting from giant cell arteritis. The pupil on the affected side typically shows poor reactivity to light, but the consensual light reaction remains normal. The typical retinal findings in CRAO include a pale retina due to edema, narrowed blood vessels, segmentation of blood columns in arteries (resembling cattle-trucking), and a cherry red spot indicating sparing of the macular center supplied by the underlying choroid. Over several weeks, optic atrophy may develop. Immediate referral to an eye specialist is necessary as CRAO is an ophthalmological emergency.
On the other hand, central retinal vein occlusion (CRVO) leads to painless and unilateral visual loss. The retina in CRVO has a distinct appearance likened to a pizza thrown against a wall. Fundoscopic examination reveals engorged retinal veins, disc edema, multiple flame-shaped hemorrhages, and cotton wool spots.
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This question is part of the following fields:
- Ophthalmology
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Question 12
Incorrect
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A 42-year-old woman comes in with a painful, red left eye and sensitivity to light. She also reports seeing floaters and experiencing a dull, throbbing headache. She is currently being evaluated by the rheumatology team for persistent pain and stiffness in her upper back and discomfort in her buttocks and thighs. Her eye appears red, and a hypopyon is visible.
What is the SINGLE most probable diagnosis?Your Answer:
Correct Answer: Anterior uveitis
Explanation:The most probable diagnosis in this case is anterior uveitis, which refers to inflammation of the iris. It typically presents with symptoms such as a painful and red eye, sensitivity to light, excessive tearing, and decreased visual clarity. The photo above shows a possible indication of this condition, with the presence of pus in the front chamber of the eye, known as hypopyon.
Anterior uveitis can have various causes, including idiopathic cases where no specific cause is identified. Other potential triggers include trauma, chronic joint diseases like spondyloarthropathies and juvenile chronic arthritis, inflammatory bowel disease, psoriasis, sarcoidosis, and infections such as Lyme disease, tuberculosis, leptospirosis, herpes simplex virus (HSV), and varicella-zoster virus (VZV). Additionally, certain malignancies like non-Hodgkin lymphoma, ocular melanoma, and retinoblastoma can be associated with anterior uveitis.
It is worth noting that there is a strong link between the HLA-B27 genotype and anterior uveitis, with approximately 50% of patients having this genetic marker. In this particular case, the likely underlying diagnosis is ankylosing spondylitis, a condition characterized by chronic pain and stiffness in the mid-spine area and sacroiliitis. It is important to mention that around 30% of men with unilateral uveitis will be found to have ankylosing spondylitis.
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This question is part of the following fields:
- Ophthalmology
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Question 13
Incorrect
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A 7-year-old girl presents with a 4-day history of blurred vision in her left eye. She is also experiencing eye pain and fatigue. On examination, her temperature is 38.0°C, but her other vital signs are normal. There is significant redness in the conjunctiva, and a collection of pus (hypopyon) is present in her left eye. Her visual acuity in that eye is reduced to counting fingers. She recently received a kitten as a pet from her parents.
What is the SINGLE most likely causative organism?Your Answer:
Correct Answer: Toxocara canis
Explanation:Toxocariasis is a rare infection caused by the parasitic roundworm Toxocara canis. The main way it spreads to humans is through contact with dog feces. However, practicing good hand hygiene can help prevent transmission. While most people who come into contact with Toxocara canis don’t show any symptoms, a small number may experience a mild flu-like illness.
The most common presentation of toxocariasis is in children, who may experience unilateral visual loss. This loss of vision is typically caused by conditions such as vitritis, macular edema, and tractional retinal detachment. It is believed that these lesions occur due to a toxic or immunoallergic reaction to the larval antigens.
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This question is part of the following fields:
- Ophthalmology
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Question 14
Incorrect
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A 40-year-old woman comes in with bitemporal hemianopia resulting from a meningioma.
Where in the visual pathway has this lesion occurred?Your Answer:
Correct Answer: Optic chiasm
Explanation:The optic chiasm is situated just below the hypothalamus and is in close proximity to the pituitary gland. When the pituitary gland enlarges, it can impact the functioning of the optic nerve at this location. Specifically, the fibres from the nasal half of the retina cross over at the optic chiasm to form the optic tracts. Compression at the optic chiasm primarily affects these fibres, resulting in a visual defect that affects peripheral vision in both eyes, known as bitemporal hemianopia. There are several causes of optic chiasm lesions, with the most common being a pituitary tumor. Other causes include craniopharyngioma, meningioma, optic glioma, and internal carotid artery aneurysm. The diagram below provides a summary of the different visual field defects that can occur at various points in the visual pathway.
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This question is part of the following fields:
- Ophthalmology
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Question 15
Incorrect
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A 60-year-old woman with uncontrolled hypertension experiences a sudden loss of vision in her left eye. The visual acuity in her left eye is reduced to hand movements only, while her right eye has a visual acuity of 6/6. Upon examining her fundi, you observe engorged retinal veins, disc edema, numerous flame-shaped hemorrhages, and cotton wool spots scattered throughout the entire retina.
What is the SINGLE most probable diagnosis?Your Answer:
Correct Answer: Central retinal vein occlusion
Explanation:Central retinal vein occlusion (CRVO) typically results in painless, one-sided vision loss. On fundoscopic examination, the retina displays a distinct appearance resembling a ‘pizza thrown against a wall’. This includes engorged retinal veins, swelling of the optic disc, multiple flame-shaped hemorrhages, and cotton wool spots. Hypertension is present in about 65% of CRVO patients, and it is more common in individuals over 65 years old.
In contrast, central retinal artery occlusion (CRAO) also causes sudden, painless, one-sided vision loss. However, the retina’s appearance in CRAO is different from CRVO. It appears pale, with narrowed blood vessels. A notable feature is the presence of a ‘cherry-red spot’ at the center of the macula, which is supplied by the underlying choroid. Examination often reveals an afferent pupillary defect.
Vitreous hemorrhage occurs when there is bleeding into the middle chamber of the eye, known as the vitreous. This can be caused by conditions such as proliferative diabetic retinopathy, trauma, or retinal detachment. The appearance of vitreous hemorrhage is described as ‘blood within a bloodless gel’, resulting in a diffuse red appearance of the retina. Unlike CRVO, there are no focal flame-shaped hemorrhages.
Diabetic maculopathy refers to the presence of diabetic eye disease within a one-disc diameter of the macula.
Wet age-related macular degeneration (ARMD) causes vision loss due to choroidal neovascularization, which leads to leakage of blood and protein beneath the macula. While there may be hemorrhages visible on the retina, the overall appearance does not match the description provided in the question.
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This question is part of the following fields:
- Ophthalmology
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Question 16
Incorrect
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A 65-year-old man has experienced a stroke affecting the blood vessels in his brain. Testing of his visual field reveals that he has a quadrantanopia in the lower left side of his vision.
Where in the visual pathway has this injury occurred?Your Answer:
Correct Answer: Upper optic radiation
Explanation:Homonymous quadrantanopia occur when there are lesions in the optic radiation. The optic tract passes through the posterolateral angle of the optic chiasm, running alongside the cerebral peduncle and inside the uncus of the temporal lobe. Eventually, it reaches the lateral geniculate body (LGN) in the thalamus. Acting as a relay center, the LGN sends axons through the optic radiation to the primary visual cortex in the occipital lobe. The upper optic radiation carries fibers from the superior retinal quadrants (which corresponds to the lower half of the visual field) and travels through the parietal lobe. On the other hand, the lower optic radiation carries fibers from the inferior retinal quadrants (which corresponds to the upper half of the visual field) and travels through the temporal lobe. Consequently, lesions in the temporal lobe can lead to superior homonymous quadrantanopia, while lesions in the parietal lobe can cause inferior homonymous quadrantanopia. The diagram below provides a summary of the different visual field defects resulting from lesions at various points in the visual pathway.
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This question is part of the following fields:
- Ophthalmology
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Question 17
Incorrect
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A 60-year-old woman comes in with intense left eye pain and vision loss in the left eye. She has experienced multiple episodes of vomiting. During the examination, there is noticeable redness around the left side of the cornea, and the left pupil is dilated and does not react to light.
What is the SINGLE most probable diagnosis?Your Answer:
Correct Answer: Closed-angle glaucoma
Explanation:Acute closed-angle glaucoma is a serious eye condition that requires immediate medical attention. It occurs when the iris pushes forward and blocks the fluid from reaching the trabecular meshwork, which is responsible for draining the eye. This blockage leads to increased pressure inside the eye and can cause damage to the optic nerve.
The main symptoms of acute closed-angle glaucoma include severe eye pain, vision loss or decreased visual acuity, redness and congestion around the cornea, swelling of the cornea, a fixed semi-dilated pupil, and nausea and vomiting. Some individuals may also experience episodes of blurred vision or seeing haloes before the onset of these symptoms.
On the other hand, chronic open-angle glaucoma is a more common form of the condition. It affects about 1 in 50 people over the age of 40 and 1 in 10 people over the age of 75. In this type of glaucoma, there is a partial blockage in the trabecular meshwork, which gradually restricts the drainage of fluid from the eye. As a result, the pressure inside the eye gradually increases, leading to optic nerve damage. Unlike acute closed-angle glaucoma, chronic open-angle glaucoma does not cause eye pain or redness. Instead, it presents slowly with a gradual loss of peripheral vision, while central vision is relatively preserved.
It is important to seek medical attention if you experience any symptoms of glaucoma, as early diagnosis and treatment can help prevent further vision loss.
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This question is part of the following fields:
- Ophthalmology
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Question 18
Incorrect
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A 12-year-old boy presents to the eye clinic with a sudden onset of acute follicular conjunctivitis in his right eye. He complains of severe eye pain and has blurred vision with a lot of watery discharge. During the examination, pseudomembrane formation is observed in his eye, and he has preauricular lymphadenopathy on the right side. The doctor informs him that he has been diagnosed with 'epidemic keratoconjunctivitis'.
What is the SINGLE most likely causative organism in this case?Your Answer:
Correct Answer: Adenovirus
Explanation:Epidemic keratoconjunctivitis is a type of viral conjunctivitis that is primarily caused by adenoviruses. This highly contagious condition tends to occur in outbreaks. It is a common cause of acute conjunctivitis and has distinct clinical features. These include the sudden onset of acute follicular conjunctivitis, severe pain in the affected eye, a significant amount of watery discharge, the presence of subconjunctival hemorrhages, potential visual changes, hyperemia and chemosis, and the possibility of membranes and pseudomembranes forming. Additionally, ipsilateral preauricular lymphadenopathy may be observed.
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This question is part of the following fields:
- Ophthalmology
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Question 19
Incorrect
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A 6-year-old boy is brought in by his father with an itchy, red and watery right eye. On examination, there is mild erythema of palpebral conjunctiva, and follicles are visible on eversion of the eyelid. Lid oedema is evident, and you can also see a few petechial subconjunctival haemorrhages. The eye appears watery, and there is no purulent discharge. He has recently recovered from a mild upper respiratory tract infection. You make a diagnosis of viral conjunctivitis.
How long does Public Health England recommend that he should be excluded from school?Your Answer:
Correct Answer: No school exclusion is necessary
Explanation:According to Public Health England, there is no recommended exclusion period for viral or bacterial conjunctivitis from school, nursery, or childminders, unless there is an outbreak or cluster of cases.
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This question is part of the following fields:
- Ophthalmology
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Question 20
Incorrect
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A 22-year-old individual comes in with a painful, itchy, red left eye. During the examination, there is noticeable redness in the conjunctiva, and follicles are observed on the inner eyelid when it is turned inside out. The patient recently had a mild and brief upper respiratory tract infection, but there are no other significant medical history details.
What is the MOST LIKELY organism responsible for this condition?Your Answer:
Correct Answer: Adenovirus
Explanation:Conjunctivitis is the most common reason for red eyes, accounting for about 35% of all eye problems seen in general practice. It occurs when the conjunctiva, the thin layer covering the white part of the eye, becomes inflamed. Conjunctivitis can be caused by an infection or an allergic reaction.
Infective conjunctivitis is inflammation of the conjunctiva caused by a viral, bacterial, or parasitic infection. The most common type of infective conjunctivitis is viral, with adenoviruses being the main culprits. Bacterial conjunctivitis is also common and is usually caused by Streptococcus pneumoniae, Staphylococcus aureus, or Haemophilus influenzae.
The symptoms of infective conjunctivitis include sudden redness of the conjunctiva, discomfort described as a gritty or burning sensation, watering of the eyes, and discharge that may temporarily blurry vision. It can be challenging to differentiate between viral and bacterial conjunctivitis based on symptoms alone.
Here are some key features that can help distinguish between viral and bacterial conjunctivitis:
Features suggestive of viral conjunctivitis:
– Mild to moderate redness of the conjunctiva
– Presence of follicles on the inner surface of the eyelids
– Swelling of the eyelids
– Small, pinpoint bleeding under the conjunctiva
– Pseudomembranes (thin layers of tissue) may form on the inner surface of the eyelids in severe cases, often caused by adenovirus
– Less discharge (usually watery) compared to bacterial conjunctivitis
– Mild to moderate itching
– Symptoms of upper respiratory tract infection and swollen lymph nodes in front of the earsFeatures suggestive of bacterial conjunctivitis:
– Purulent or mucopurulent discharge with crusting of the eyelids, which may cause them to stick together upon waking
– Mild or no itching
– Swollen lymph nodes in front of the ears, which are often present in severe bacterial conjunctivitis
– If the discharge is copious and mucopurulent, infection with Neisseria gonorrhoeae should be considered.By considering these distinguishing features, healthcare professionals can better diagnose and manage cases of conjunctivitis.
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This question is part of the following fields:
- Ophthalmology
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Question 21
Incorrect
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A 45-year-old woman has been diagnosed with a brain tumor. Visual field testing shows that she has a left-sided superior homonymous quadrantanopia.
Where in the visual pathway has this lesion occurred?Your Answer:
Correct Answer: Lower optic radiation
Explanation:Homonymous quadrantanopias occur when there are lesions in the optic radiation. The optic tract passes through the posterolateral angle of the optic chiasm, running alongside the cerebral peduncle and inside the uncus of the temporal lobe. Eventually, it reaches the lateral geniculate body (LGN) in the thalamus. Acting as a relay center, the LGN sends axons through the optic radiation to the primary visual cortex in the occipital lobe. The upper optic radiation carries fibers from the superior retinal quadrants (which corresponds to the lower half of the visual field) and travels through the parietal lobe. On the other hand, the lower optic radiation carries fibers from the inferior retinal quadrants (which corresponds to the upper half of the visual field) and travels through the temporal lobe. Consequently, lesions in the temporal lobe can lead to superior homonymous quadrantanopias, while lesions in the parietal lobe can cause inferior homonymous quadrantanopias. The diagram below provides a summary of the different visual field defects resulting from lesions at various points in the visual pathway.
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This question is part of the following fields:
- Ophthalmology
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Question 22
Incorrect
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A 35-year-old traveler returns from a trip to Thailand with a painful, red right eye. The eye has been bothering him for the past two and a half weeks, and the onset of the irritation has been gradual. There has been mild mucopurulent discharge present in the eye for the past two weeks, and he states that he has to clean the eye regularly. On examination, you note the presence of right-sided, nontender pre-auricular lymphadenopathy. On further questioning, he admits to visiting a sex worker during his visit to Thailand.
Which of the following antibiotics would be most appropriate to prescribe for this patient?Your Answer:
Correct Answer: Doxycycline
Explanation:Sexually transmitted eye infections can be quite severe and are often characterized by prolonged mucopurulent discharge. The two main causes of these infections are Chlamydia trachomatis and Neisseria gonorrhoea. Differentiating between the two can be done by considering certain features.
Chlamydia trachomatis infection typically presents with chronic low-grade irritation and mucous discharge that lasts for more than two weeks in sexually active individuals. Pre-auricular lymphadenopathy, or swelling of the lymph nodes in front of the ear, may also be present. Most cases of this infection are unilateral, affecting only one eye, but there is a possibility of it being bilateral, affecting both eyes.
On the other hand, Neisseria gonorrhoea infection tends to develop rapidly, usually within 12 to 24 hours. It is characterized by copious mucopurulent discharge, swelling of the eyelids, and tender preauricular lymphadenopathy. This type of infection carries a higher risk of complications, such as uveitis, severe keratitis, and corneal perforation.
Based on the patient’s symptoms, it appears that they are more consistent with a Chlamydia trachomatis infection, especially considering the slower and more gradual onset of their symptoms.
There is ongoing debate regarding the most effective antibiotic treatment for these infections. Some options include topical tetracycline ointment to be applied four times a day for six weeks, oral doxycycline to be taken twice a day for one to two weeks, oral azithromycin with a single dose of 1 gram followed by 500 mg orally for two days, or oral erythromycin to be taken four times a day for one week.
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This question is part of the following fields:
- Ophthalmology
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Question 23
Incorrect
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A 30-year-old construction worker comes in with intense pain in his left eye following an incident at the job site where a significant amount of cement dust entered his left eye.
Which of the following long-term complications is the LEAST probable to develop?Your Answer:
Correct Answer: Open-angle glaucoma
Explanation:Cement contains lime, which is a powerful alkali, and this can cause a serious eye emergency that requires immediate treatment. Alkaline chemicals, such as oven cleaner, ammonia, household bleach, drain cleaner, oven cleaner, and plaster, can also cause damage to the eyes. They lead to colliquative necrosis, which is a type of tissue death that results in liquefaction. On the other hand, acids cause damage through coagulative necrosis. Common acids that can harm the eyes include toilet cleaners, certain household cleaning products, and battery fluid.
The initial management of a patient with cement or alkali exposure to the eyes should be as follows:
1. Irrigate the eye with a large amount of normal saline for 20-30 minutes.
2. Administer local anaesthetic drops every 5 minutes to help keep the eye open and alleviate pain.
3. Monitor the pH every 5 minutes until a neutral pH (7.0-7.5) is achieved. Briefly pause irrigation to test the fluid from the forniceal space using litmus paper.After the initial management, a thorough examination should be conducted, which includes the following steps:
1. Examine the eye directly and with a slit lamp.
2. Remove any remaining cement debris from the surface of the eye.
3. Evert the eyelids to check for hidden cement debris.
4. Administer fluorescein drops and check for corneal abrasion.
5. Assess visual acuity, which may be reduced.
6. Perform fundoscopy to check for retinal necrosis if the alkali has penetrated the sclera.
7. Measure intraocular pressure through tonometry to detect secondary glaucoma.Once the eye’s pH has returned to normal, irrigation can be stopped, and the patient should be promptly referred to an ophthalmology specialist for further evaluation.
Potential long-term complications of cement or alkali exposure to the eyes include closed-angle glaucoma, cataract formation, entropion, keratitis sicca, and permanent vision loss.
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This question is part of the following fields:
- Ophthalmology
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Question 24
Incorrect
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A 12-year-old boy comes in with complaints of double vision. He is holding his head tilted to the left-hand side. During the examination of his eye movements, it is observed that both eyes can look normally to the right, but on looking to the left, his left eye cannot turn outwards past the midline. The right eye is unaffected when looking to the left.
Which muscle is the MOST likely to be involved in this case?Your Answer:
Correct Answer: Lateral rectus
Explanation:This patient is experiencing a condition called right-sided abducens nerve palsy, which means that their sixth cranial nerve is paralyzed. As a result, the lateral rectus muscle, which is responsible for moving the eye outward, is also paralyzed. This means that the patient’s right eye is unable to turn outward. This can lead to a condition called convergent strabismus, where the eyes are not aligned properly, and diplopia, which is double vision. To compensate for the double vision, patients often tilt their head towards the side of the paralyzed muscle.
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This question is part of the following fields:
- Ophthalmology
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Question 25
Incorrect
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A 25-year-old patient comes in with a painful and red left eye. Upon examination, you observe conjunctival erythema and the presence of mucopurulent discharge and lid crusting. Based on these findings, you diagnose the patient with bacterial conjunctivitis. However, the patient cannot use the first-line treatment due to a previous reaction. According to the current NICE guidance, what is the recommended second-line antibiotic for managing bacterial conjunctivitis?
Your Answer:
Correct Answer: Fusidic acid 1% drops
Explanation:When it comes to managing bacterial conjunctivitis, NICE provides some helpful guidance. It is important to inform the patient that most cases of bacterial conjunctivitis will resolve on their own within 5-7 days without any treatment. However, in severe cases or situations where a quick resolution is necessary, topical antibiotics may be necessary. In some cases, it may be appropriate to delay treatment and advise the patient to start using topical antibiotics if their symptoms have not improved within 3 days.
There are a few options for topical antibiotics that can be used. One option is Chloramphenicol 0.5% drops, which should be applied every 2 hours for 2 days and then 4 times daily for 5 days. Another option is Chloramphenicol 1% ointment, which should be applied four times daily for 2 days and then twice daily for 5 days. Fusidic acid 1% eye drops can also be used as a second-line treatment and should be applied twice daily for 7 days.
By following these guidelines, healthcare professionals can effectively manage bacterial conjunctivitis and provide appropriate treatment options for their patients.
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This question is part of the following fields:
- Ophthalmology
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Question 26
Incorrect
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A 42-year-old woman comes in with a painful, red left eye and sensitivity to light. She also reports seeing floaters and experiencing a dull, throbbing headache. She is currently being evaluated by the rheumatology team for persistent pain and stiffness in her upper back and discomfort in her buttocks and thighs. Her eye appears red, and a hypopyon is visible.
What is the SINGLE most probable UNDERLYING diagnosis?Your Answer:
Correct Answer: Ankylosing spondylitis
Explanation:The most probable diagnosis in this case is anterior uveitis. Anterior uveitis refers to the inflammation of the iris and typically manifests as a painful and red eye. It is often accompanied by symptoms such as sensitivity to light, excessive tearing, and decreased visual clarity. In some instances, there may be the presence of pus in the front part of the eye known as hypopyon.
Anterior uveitis can have various causes, including idiopathic (no known cause), trauma, chronic joint diseases like spondyloarthropathies and juvenile chronic arthritis, inflammatory bowel disease, psoriasis, sarcoidosis, and infections such as Lyme disease, tuberculosis, leptospirosis, herpes simplex virus (HSV), and varicella-zoster virus (VZV). Additionally, certain malignancies like non-Hodgkin lymphoma, ocular melanoma, and retinoblastoma can also be associated with anterior uveitis.
A significant association has been observed between the HLA-B27 genotype and anterior uveitis, with approximately 50% of patients having this genetic marker. In this particular case, the likely underlying diagnosis is ankylosing spondylitis, a condition characterized by chronic pain and stiffness in the middle spine area and sacroiliitis. It is worth noting that around 30% of men with unilateral uveitis will be found to have ankylosing spondylitis.
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This question is part of the following fields:
- Ophthalmology
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Question 27
Incorrect
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A 35-year-old woman comes in with a painful, red right eye. She has a history of ankylosing spondylitis (AS).
What is the MOST frequently occurring eye complication associated with AS?Your Answer:
Correct Answer: Uveitis
Explanation:Uveitis is the most prevalent eye complication that arises in individuals with ankylosing spondylitis (AS). Approximately one out of every three patients with AS will experience uveitis at some stage. The symptoms of uveitis include a red and painful eye, along with photophobia and blurred vision. Additionally, patients may notice the presence of floaters. The primary treatment for uveitis involves the use of corticosteroids, and it is crucial for patients to seek immediate attention from an ophthalmologist.
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This question is part of the following fields:
- Ophthalmology
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Question 28
Incorrect
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A 35-year-old woman comes in after being hit in the eye by a piece of metal at her workplace. She has a deep cut on her upper eyelid and is experiencing intense eye pain and decreased vision.
What would be the most useful approach for initially assessing this patient?Your Answer:
Correct Answer: The Seidel test
Explanation:The Seidel test is a method used to assess ocular trauma. The procedure involves applying a 10% fluorescein strip to the affected area and examining it using a cobalt blue filter. If there is a corneal laceration with leakage of aqueous fluid, the dye will be diluted by the fluid, resulting in a visible stream.
In addition to the Seidel test, there are several other important steps to be taken during an eye examination for trauma. These include inspecting the overall appearance of the eye, examining the lids and peri-orbital bones, assessing visual acuity in both eyes, testing visual fields by confrontation, evaluating eye movements, measuring pupil size and response to light and accommodation, checking for foreign bodies using a slit lamp, performing fundoscopy and assessing the red reflex.
The Amsler grid test is a useful tool for detecting central visual field defects and aiding in the diagnosis of age-related macular degeneration. A positive Amsler test is indicated by the appearance of curved or wavy lines on the grid.
Tonometry is a technique used to measure intraocular pressure (IOP), which is helpful in diagnosing glaucoma.
Retinal photography is a sophisticated imaging process that involves using a digital camera to capture detailed pictures of the retina. It is primarily used to document the health of various structures in the eye, such as the optic nerve, posterior pole, macula, retina, and its blood vessels. However, it is not typically used as part of the initial evaluation for trauma.
Eye pH measurement is a valuable tool in evaluating chemical eye injuries.
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This question is part of the following fields:
- Ophthalmology
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Question 29
Incorrect
-
A 30-year-old construction worker comes in with intense pain in his left eye following an incident at the job site where a significant amount of cement dust blew into his eye.
What should be utilized as an irrigation solution for the affected eye?Your Answer:
Correct Answer: 0.9% normal saline
Explanation:Cement contains lime, which is a powerful alkali, and this can cause a serious eye emergency that requires immediate treatment. Alkaline chemicals, such as oven cleaner, ammonia, household bleach, drain cleaner, oven cleaner, and plaster, can also cause damage to the eyes. They lead to colliquative necrosis, which is a type of tissue death that results in liquefaction. On the other hand, acids cause damage through coagulative necrosis. Common acids that can harm the eyes include toilet cleaners, certain household cleaning products, and battery fluid.
The initial management of a patient with cement or alkali exposure to the eyes should be as follows:
1. Irrigate the eye with a large amount of normal saline for 20-30 minutes.
2. Administer local anaesthetic drops every 5 minutes to help keep the eye open and alleviate pain.
3. Monitor the pH every 5 minutes until a neutral pH (7.0-7.5) is achieved. Briefly pause irrigation to test the fluid from the forniceal space using litmus paper.After the initial management, a thorough examination should be conducted, which includes the following steps:
1. Examine the eye directly and with a slit lamp.
2. Remove any remaining cement debris from the surface of the eye.
3. Evert the eyelids to check for hidden cement debris.
4. Administer fluorescein drops and check for corneal abrasion.
5. Assess visual acuity, which may be reduced.
6. Perform fundoscopy to check for retinal necrosis if the alkali has penetrated the sclera.
7. Measure intraocular pressure through tonometry to detect secondary glaucoma.Once the eye’s pH has returned to normal, irrigation can be stopped, and the patient should be promptly referred to an ophthalmology specialist for further evaluation.
Potential long-term complications of cement or alkali exposure to the eyes include closed-angle glaucoma, cataract formation, entropion, keratitis sicca, and permanent vision loss.
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This question is part of the following fields:
- Ophthalmology
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Question 30
Incorrect
-
A 30-year-old construction worker comes in with intense pain in his right eye following an incident at the job site where a significant amount of cement dust entered his right eye.
What is the potential pathological condition that this patient's eye may be susceptible to?Your Answer:
Correct Answer: Colliquative necrosis
Explanation:Cement contains lime, which is a powerful alkali, and this can cause a serious eye emergency that requires immediate treatment. Alkaline chemicals, such as oven cleaner, ammonia, household bleach, drain cleaner, oven cleaner, and plaster, can also cause damage to the eyes. They lead to colliquative necrosis, which is a type of tissue death that results in liquefaction. On the other hand, acids cause damage through coagulative necrosis. Common acids that can harm the eyes include toilet cleaners, certain household cleaning products, and battery fluid.
The initial management of a patient with cement or alkali exposure to the eyes should be as follows:
1. Irrigate the eye with a large amount of normal saline for 20-30 minutes.
2. Administer local anaesthetic drops every 5 minutes to help keep the eye open and alleviate pain.
3. Monitor the pH every 5 minutes until a neutral pH (7.0-7.5) is achieved. Briefly pause irrigation to test the fluid from the forniceal space using litmus paper.After the initial management, a thorough examination should be conducted, which includes the following steps:
1. Examine the eye directly and with a slit lamp.
2. Remove any remaining cement debris from the surface of the eye.
3. Evert the eyelids to check for hidden cement debris.
4. Administer fluorescein drops and check for corneal abrasion.
5. Assess visual acuity, which may be reduced.
6. Perform fundoscopy to check for retinal necrosis if the alkali has penetrated the sclera.
7. Measure intraocular pressure through tonometry to detect secondary glaucoma.Once the eye’s pH has returned to normal, irrigation can be stopped, and the patient should be promptly referred to an ophthalmology specialist for further evaluation.
Potential long-term complications of cement or alkali exposure to the eyes include closed-angle glaucoma, cataract formation, entropion, keratitis sicca, and permanent vision loss.
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This question is part of the following fields:
- Ophthalmology
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