Iris Abnormalities

Question 1

What is anisocoria?

How can it be caused? (Pathological, Drugs)

Answer 1

• unequal pupil sizes
• could be defect in efferent nerve pathway or physical lesions
• Caused by Pilocarpine, cocaine, tropicamide, scopolamine

Question 2

How do you distinguish which pupil is abnormal in anisocoria and what pathway (sympathetic or parasympathetic) is affect?
Also, which one Horner’s and oculomotor nerve palsy?
(Between smaller and larger pupil)

Answer 2

• Smaller: will not dilate in dim light, sympathetic damage (i.e. Horner’s)
• Larger: will not contract in response to light, parasympathetic damage, (i.e. oculomotor nerve palsy)

Question 3

If you have anisocoria and the presence of decreased mental status, confusion or severe headache what pathology sign could that indicate (also, what treatment is required?)

Answer 3

• May indicate, bloor or tumor pressing on critical nerves.

- Treatment: neurosurgical emergency

Question 4

What is a coloboma?

Describe the defect on the iris, is it bilateral, where on the iris is it?

Answer 4

• tissue cleft from incomplete fusion of fetal fissure
• bilateral
• inferior nasal

Question 5

What is the impact of coloboma in VA/accomodation, possible subluxation and treatment?

Answer 5

• No impact on VA/accomodation
• May lead to lens subluxation
• No Tx:may use contact lens

Question 6

What is corectopia and pseudopolycoria?

Answer 6

• Corectopia: displacement of the pupil from its normal central location
• Pseudopolycoria: more than one opening in the iris

Question 7

What is Axenfeld’s anomoly?

Hint: Peripheral anterior segment defect

Answer 7

:posterior embryotoxon (thickened anterior schwalbe’s line) and peripheral anterior synechaie

Question 8

What is Reiger’s anomoly and how is it different than Reiger’s syndrome?

Answer 8

• Reiger’s Anomoly: Axenfeld’s anomoly with iris and pupil abnormalities (corectopia)
• Reiger’s Sydrome: Ocular anomalies and systemic developmental defects (dental, craniofacial and skeletal)

Question 9

What are 4 signs of Axenfeld-Reiger’s and what ocular disease should you check for?

Answer 9

• Bilateral posterior embyrotoxon with iris strands attached
• Peripheral anterior synechiae and hypoplasia of anterior stroma or the iris
• Iris atrophy and misshapen pupil (discoria)
• Dental, craniofacial and skeletal abnormalities
• Check for glaucoma

Question 10

Describe aniridia

Is it bilateral/genetic?, what structures are changed, what 4 ocular signs

Answer 10

• absence of iris tissue
• bilateral, genetic
• corneal, lenticular, fundus changes
• photophobia, nystagmus, decreased vision, strabismus

Question 11

What are the signs of each type of aniridia?

A. AN-1 (isolated)
B. AN-2 (Miller’s syndrome)
C. AN-3 (Gillespie Syndrome)

Answer 11

• AN-1: most common
• AN-2: associated with Wilm’s tumor, genitourinary anomolies
• AN-3: mental handicap and cerebellar ataxia

Question 12

Which is not an anterior segment signs of aniridia?

A. corneal opacities
B. microcornea
C. Corneal inflammation
D. Sclerocornea
E. dermoids (enlarged cornea)

Answer 12

C. Corneal inflammation

Question 13

Which is not a lenticular sign of aniridia?

A. Subluxation
B. Aphakia
C. Opacity (Cataract)
D. Absence
E. PPM

Answer 13

B. Aphakia

Question 14

Which is not a fundus sign of aniridia?

A. Foveal hypoplasia
B. Optic Nerve hypoplasia
C. Choroidal colobomas
D. Macular hypoplasia

Answer 14

D. Macular hypoplasia

Question 15

Which are other signs of aniridia?

A. Nystagmus
B. Mental Retardation
C. Secondary Glaucoma
D. Primary Glaucoma

Answer 15

D. Primary Glaucoma

Question 16

Describe ectropian uvea (Congenital and rare)

Answer 16

• Congenital: rare, non-progressive. Pigmented posterior iris extends over anterior iris
• follows glaucoma, could be bilateral