OPHTHALMIC SURGICAL ASSISTANT EXAM 2026
SECTION 1: ANATOMY AND PHYSIOLOGY
1. Which layer of the eye contains the photoreceptor cells?
A. Cornea
B. Sclera
C. Retina
D. Choroid
Correct Answer: C. Retina
Rationale: The retina contains rods and cones, the specialized photoreceptor cells responsible for
converting light into electrical impulses that are transmitted to the brain through the optic nerve. The
cornea and sclera are protective structures, while the choroid supplies blood to the retina.
2. Which muscle constricts the pupil?
A. Dilator pupillae
B. Sphincter pupillae
C. Superior rectus
D. Lateral rectus
Correct Answer: B. Sphincter pupillae
Rationale: The sphincter pupillae muscle is controlled by the parasympathetic nervous system and
causes pupillary constriction (miosis). The dilator pupillae enlarges the pupil.
3. The transparent structure responsible for most of the eye's refractive power is:
A. Lens
B. Iris
C. Cornea
D. Retina
Correct Answer: C. Cornea
Rationale: The cornea contributes approximately two-thirds of the eye's refractive power because of
its curved surface and transparent nature.
4. Aqueous humor is produced by the:
A. Retina
B. Ciliary body
C. Optic nerve
D. Lens
,Correct Answer: B. Ciliary Body
Rationale: The ciliary processes of the ciliary body continuously produce aqueous humor, which
nourishes the cornea and lens while maintaining intraocular pressure.
5. Which cranial nerve controls most extraocular muscles?
A. CN II
B. CN III
C. CN VII
D. CN VIII
Correct Answer: B. CN III (Oculomotor Nerve)
Rationale: The oculomotor nerve innervates the superior rectus, inferior rectus, medial rectus, and
inferior oblique muscles, as well as the levator palpebrae superioris.
6. The optic disc is also known as the:
A. Macula
B. Blind spot
C. Fovea
D. Ora serrata
Correct Answer: B. Blind Spot
Rationale: The optic disc lacks photoreceptors because it is the site where the optic nerve exits the
eye, creating the physiologic blind spot.
7. The fovea is responsible for:
A. Peripheral vision
B. Color vision and sharp central vision
C. Night vision only
D. Tear production
Correct Answer: B
Rationale: The fovea contains the highest concentration of cone photoreceptors, providing the
sharpest visual acuity and color discrimination.
8. Which structure separates the anterior and posterior chambers?
A. Retina
B. Lens
C. Iris
D. Cornea
Correct Answer: C. Iris
, Rationale: The iris divides the aqueous-filled anterior segment into anterior and posterior chambers.
9. Rod photoreceptors are primarily responsible for:
A. Color vision
B. Daylight vision
C. Night vision
D. Accommodation
Correct Answer: C
Rationale: Rods function in dim illumination and are highly sensitive to light but do not detect color.
10. The normal intraocular pressure range is:
A. 1–5 mmHg
B. 5–10 mmHg
C. 10–21 mmHg
D. 25–40 mmHg
Correct Answer: C
Rationale: Normal intraocular pressure is generally considered to be between 10 and 21 mmHg.
Values outside this range may indicate ocular pathology such as glaucoma.
SECTION 2: CATARACT SURGERY
11. The most common cataract surgery technique is:
A. ECCE
B. ICCE
C. Phacoemulsification
D. Keratoplasty
Correct Answer: C
Rationale: Phacoemulsification uses ultrasound energy to break up and remove the cataract through
a small incision, allowing faster recovery and fewer complications.
12. During cataract surgery, the cloudy natural lens is replaced with a:
A. Corneal graft
B. Vitreous substitute
C. Intraocular lens (IOL)
D. Contact lens
Correct Answer: C
Rationale: An intraocular lens restores focusing power after removal of the cataractous lens.
SECTION 1: ANATOMY AND PHYSIOLOGY
1. Which layer of the eye contains the photoreceptor cells?
A. Cornea
B. Sclera
C. Retina
D. Choroid
Correct Answer: C. Retina
Rationale: The retina contains rods and cones, the specialized photoreceptor cells responsible for
converting light into electrical impulses that are transmitted to the brain through the optic nerve. The
cornea and sclera are protective structures, while the choroid supplies blood to the retina.
2. Which muscle constricts the pupil?
A. Dilator pupillae
B. Sphincter pupillae
C. Superior rectus
D. Lateral rectus
Correct Answer: B. Sphincter pupillae
Rationale: The sphincter pupillae muscle is controlled by the parasympathetic nervous system and
causes pupillary constriction (miosis). The dilator pupillae enlarges the pupil.
3. The transparent structure responsible for most of the eye's refractive power is:
A. Lens
B. Iris
C. Cornea
D. Retina
Correct Answer: C. Cornea
Rationale: The cornea contributes approximately two-thirds of the eye's refractive power because of
its curved surface and transparent nature.
4. Aqueous humor is produced by the:
A. Retina
B. Ciliary body
C. Optic nerve
D. Lens
,Correct Answer: B. Ciliary Body
Rationale: The ciliary processes of the ciliary body continuously produce aqueous humor, which
nourishes the cornea and lens while maintaining intraocular pressure.
5. Which cranial nerve controls most extraocular muscles?
A. CN II
B. CN III
C. CN VII
D. CN VIII
Correct Answer: B. CN III (Oculomotor Nerve)
Rationale: The oculomotor nerve innervates the superior rectus, inferior rectus, medial rectus, and
inferior oblique muscles, as well as the levator palpebrae superioris.
6. The optic disc is also known as the:
A. Macula
B. Blind spot
C. Fovea
D. Ora serrata
Correct Answer: B. Blind Spot
Rationale: The optic disc lacks photoreceptors because it is the site where the optic nerve exits the
eye, creating the physiologic blind spot.
7. The fovea is responsible for:
A. Peripheral vision
B. Color vision and sharp central vision
C. Night vision only
D. Tear production
Correct Answer: B
Rationale: The fovea contains the highest concentration of cone photoreceptors, providing the
sharpest visual acuity and color discrimination.
8. Which structure separates the anterior and posterior chambers?
A. Retina
B. Lens
C. Iris
D. Cornea
Correct Answer: C. Iris
, Rationale: The iris divides the aqueous-filled anterior segment into anterior and posterior chambers.
9. Rod photoreceptors are primarily responsible for:
A. Color vision
B. Daylight vision
C. Night vision
D. Accommodation
Correct Answer: C
Rationale: Rods function in dim illumination and are highly sensitive to light but do not detect color.
10. The normal intraocular pressure range is:
A. 1–5 mmHg
B. 5–10 mmHg
C. 10–21 mmHg
D. 25–40 mmHg
Correct Answer: C
Rationale: Normal intraocular pressure is generally considered to be between 10 and 21 mmHg.
Values outside this range may indicate ocular pathology such as glaucoma.
SECTION 2: CATARACT SURGERY
11. The most common cataract surgery technique is:
A. ECCE
B. ICCE
C. Phacoemulsification
D. Keratoplasty
Correct Answer: C
Rationale: Phacoemulsification uses ultrasound energy to break up and remove the cataract through
a small incision, allowing faster recovery and fewer complications.
12. During cataract surgery, the cloudy natural lens is replaced with a:
A. Corneal graft
B. Vitreous substitute
C. Intraocular lens (IOL)
D. Contact lens
Correct Answer: C
Rationale: An intraocular lens restores focusing power after removal of the cataractous lens.
