Eyes - clinical questions
The mother of a 2-year-old boy complains about her son's eye. Physical examination reveals two small red bumps and localized swelling on the outside of the patient's top right eyelid. Acute inflammation of which of the following structures most likely caused the stye observed in this patient? (A) Conjunctiva (B) Dermis (C) Lacrimal gland (D) Sebaceous gland of Zeis (E) Tarsus
Sebaceous gland of Zeis
A 39-year-old woman afflicted with corneal perforation receives a corneal transplant. Her vision is restored. The corneal graft is well tolerated and becomes fully integrated with the patient's other ocular tissues. Which of the following structural features provides the best explanation for why the corneal graft is not rejected by the recipient? (A) Basal cells of the corneal epithelium are able to regenerate. (B) The Bowman membrane protects against the spread of infections. (C) Collagen fibers are regularly packed. (D) Cornea is avascular and lacks lymphatic drainage. (E) Regeneration of the Descemet membrane assists wound healing.
(D) Cornea is avascular and lacks lymphatic drainage.
A 14-year-old girl with a 4-year history of type 1 diabetes presents with blurred vision. Ophthalmic examination reveals "snowflake" cataracts. Which of the following abnormalities accounts for the pathogenesis of cataracts in this patient? (A) Accumulation of sorbitol in the lens (B) Increased anteroposterior diameter of the eye (C) Increased intraocular pressure (D) Macular degeneration (E) Retinitis pigmentosa
Accumulation of sorbitol in the lens
A 72-year-old woman with a history of coronary heart disease complains of blurred vision in her left eye. Funduscopic examination reveals a cherry-red spot. Which of the following abnormalities underlies this pathologic finding? (A) Cataract (B) Central retinal artery occlusion (C) Central retinal vein occlusion (D) Melanoma (E) Retinal detachment
Central retinal artery occlusion
A 28-year-old man presents with pain, tearing, and the sense of a foreign object in his left eye. A tiny dust particle is observed and carefully removed. Minor corneal abrasions caused by the dust particle are also noted. After a few days, the scratches on the cornea have completely disappeared. Stem cells that populate the basal layer of the corneal epithelium and facilitate the healing of corneal abrasions originate from which of the following locations? (A) Blood vessels in the sclera (B) Bowman membrane (C) Corneal stroma (D) Corneoscleral limbus (E) Descemet membrane
Corneoscleral limbus
A 37-year-old woman complains that her right pupil is smaller than her left pupil. Physical examination confirms this observation and further reveals that the patient's right hand is atrophic, warm, and dry. A subsequent neurological examination demonstrates an interruption of the patient's right cervical sympathetic trunk. Which of the following mechanisms of disease explains constriction of the patient's right pupil? (A) Increased tension of the zonular fibers (B) Paralysis of the ciliary muscle (C) Paralysis of the dilator pupillae (D) Tonic contraction of the ciliary muscle (E) Tonic contraction of the sphincter pupillae
Paralysis of the dilator pupillae
A 48-year-old man loses vision in his right eye after an automobile accident. Funduscopy reveals intraocular hemorrhage and detachment of the retina. Retinal detachment occurs between which of the following paired tissue layers? (A) Bipolar cell layer and ganglion cell layer (B) Bruch membrane and retinal pigmented epithelium (C) Choroid and Bruch membrane (D) Outer nuclear layer and inner nuclear layer (E) Retinal pigmented epithelium and retinal photoreceptor layer
Retinal pigmented epithelium and retinal photoreceptor layer
An 18-year-old man is color-blind and fails his physical examination for military pilot training. Deficiency in which of the following cells accounts for his color blindness? (A) Bipolar (B) Cone (C) Ganglion (D) Müller (E) Rod
cone
A 45-year-old Asian woman complains itching and irritation in both eyes. Physical examination reveals photophobia and fibrovascular opacity in the superior cornea (shown in the image). Histological examination of a conjunctival scraping exhibits cytoplasmic inclusion bodies. Which of the following best describes these clinicopathologic findings? (A) Conjunctivitis (B) Corneal ulceration (C) Iritis (D) Keratitis (E) Scleritis
conjunctivitis
A 29-year-old man with myopia inquires about the benefits of LASIK (laser-assisted in situ keratomileusis) surgery to correct and improve vision. You explain to him that LASIK surgery reshapes which of the following components of the eye? (A) Cornea (B) Iris (C) Lens (D) Retina (E) Vitreous body
cornea
A 7-year-old girl complains of pain, excessive tearing, and decreased vision in her left eye. She was diagnosed with a herpes simplex virus infection 6 months ago. Physical examination reveals multiple, minute corneal ulcers. Which of the following structures is primarily affected in this superficial punctate keratopathy? (A) Corneal endothelium (B) Corneal epithelium (C) Iris (D) Lacrimal gland (E) Lens
corneal epithelium
A 23-year-old man who wears contact lenses complains of severe pain, foreign body sensation, and photophobia in his right eye. Physical examination reveals localized roughening of the corneal epithelium. The patient is subsequently diagnosed with recurrent corneal erosion. Separation between which of the following pairs of structures underlies this patient's condition? (A) Bowman membrane and corneal stroma (B) Corneal epithelium and Bowman membrane (C) Corneal stroma and Descemet membrane (D) Descemet membrane and corneal endothelium (E) Neighboring epithelial cells
corneal epithelium and bowman membrane
When reading, detailed patterns of letters on the printed page are detected primarily in which of the following areas of the retina? (A) Fovea (B) Lamina cribrosa (C) Macula lutea (D) Optic disc (E) Optic papilla
fovea
A 56-year-old woman complains of decreased vision in her left eye of 4 years' duration. White discoloration of her left pupil is noted on physical examination (shown in the image). The white appearance of the pupil in this patient represents a pathologic change affecting which of the following components of the eye? (A) Conjunctiva (B) Cornea (C) Iris (D) Lens (E) Vitreous body
lens
A 72-year-old man complains that he has had poor vision for 3 years. Ophthalmic examination reveals a loss of central vision, although the patient's peripheral vision remains unaffected. Which of the following structures is most likely affected? (A) Cornea (B) Iris (C) Lens (D) Macula lutea (E) Optic nerve
macula lutea
In the image described in Questions 27 and 28, the inner limiting membrane indicated by the arrowhead is produced by which of the following cells? (A) Amacrine (B) Bipolar (C) Cone and rod (D) Ganglion (E) Müller
muller
Corneal epithelium is composed of which of the following types of tissue? (A) Keratinized stratified squamous epithelium (B) Nonkeratinized stratified squamous epithelium (C) Pseudostratified epithelium (D) Stratified columnar epithelium (E) Stratified cuboidal epithelium
non-keratinized stratified squamous epithelium
A 39-year-old woman complains of double vision. During the physical examination, you notice that the patient is unable to abduct her left eye, suggesting paralysis of the lateral rectus muscle. The patient is subsequently diagnosed with abducent nerve palsy. The lateral rectus muscle inserts to which of the following components of the eye? (A) Conjunctiva (B) Lens (C) Retina (D) Sclera (E) Uvea
sclera
You are looking in the mirror and examining your eye. You notice that your pupils are black. Which of the following structures gives a black appearance to the pupils? (A) Aqueous humor (B) Iris (C) Lens (D) Uvea (E) Vitreous body
uvea
The primary visual cortex that processes and interprets the visual image captured by the retina is located in which of the following parts of the central nervous system? (A) Frontal lobe (B) Occipital lobe (C) Parietal lobe (D) Temporal lobe (E) Thalamus
Occipital lobe
A 54-year-old woman complains blurry vision when reading. Her vision of distant objects is fine. Which of the following age-related changes underlies presbyopia in this patient? (A) Dilated pupil (B) Flattened lens (C) Opacity of the lens (D) Relaxed zonular fibers (E) Rounded lens
Flattened lens
A 68-year-old woman complains of gradual vision loss over the past year. Ophthalmic examination reveals elevated intraocular pressure. Funduscopic examination reveals optic cupping. The patient is subsequently diagnosed with open-angle glaucoma. Which of the following mechanisms of disease is associated with this patient's medical condition? (A) Corneal abrasion (B) Degeneration of the choroid (C) Degeneration of the lens (D) Increased resistance to the outflow of the aqueous humor (E) Retinal ischemia
Increased resistance to the outflow of the aqueous humor
A 62-year-old man presents with persistent headaches and gradual visual field loss in his right eye. Ophthalmic examination demonstrates high intraocular pressure. The patient is subsequently diagnosed with closed-angle glaucoma, caused by inadequate drainage of aqueous humor. Which of the following structures in the eye produces aqueous humor? (A) Choroid (B) Corneal endothelial cells (C) Corneal epithelial cells (D) Nonpigmented epithelial cells of the ciliary process (E) Pigment epithelial cells of ciliary process
Nonpigmented epithelial cells of the ciliary process
