Non-Strabismic Anomalies of Heterophorias

Question 1

Exo at near is greater than exo at far
Receded NPC
Low MEM
Low BO
Low NRA
Low AC/A ratio
Myope: full correct with Base in prism Hyperope: under correct Base in prism

Answer 1

Convergence insufficiency/weakness Exo

Question 2

• Exophoria at far & at near are the same
• Normal NPC
• Low MEM
• Low BO at far & near
• Low NRA
• NormalAc/Aratio
• Tx: over-minus at distance & near

Answer 2

Basic Exophoria

Question 3

• Exophoria at far is greater than exophoria at near
• Normal NPC
• Normal MEM
• Low BO at far & low BI at near
• Normal NRA & PRA
• High AC/A ratio
• Tx: over minus at distance, maybe bifocals
• Hyperope - undercorrect

Answer 3

Divergence Excess Exophoria

Question 4

• Esophoria at far is greater than esophoria at near
• Normal NPC
• Normal MEM
• Low BI at far
• Normal NRA
• Low AC/A ratio
• Tx: maximum plus at distance

Answer 4

Divergence Insufficiency / Weakness Esophoria

Question 5

• Esophoria at far & near are the same
• Normal NPC
• High MEM
• Low BI at far & near
• Low PRA
• Normal AC/A ratio
• Tx: maximum plus, bifocals/PAL may help at near

Answer 5

Basic Esophoria

Question 6

• Esophoria at near is greater than esophoria at far
• Normal NPC
• High MEM
• Low BI
• Low PRA
• High AC/A ratio
• Tx: bifocals

Answer 6

Convergence Excess Esophoria