LOW AC/A VERGENCE DISORDERS

Question 1

define CI

Answer 1

Insufficient convergence at near that leads to a Greater XP at near than distance (>8PD).

Question 2

symptoms of CI

Answer 2

• Asthenopia // HA intermittent diplopia w/ near task.
• Symptoms worsen thru the day.

Question 3

what are the signs of CI?

Answer 3

Primary Test:
* CT: greater XP at near than distance (>8PD)
* NPC: reduced (non-acc target)
* PFV (NBO): reduced
* PFV (DBO): normal
* Vergence Fac: difficulty w/ BO

Secondary Test:
* NRA: reduced
* PRA: normal
* BAF: difficulty w/ + lenses
* MAF: normal

Tertiary Test:
* BCC/MEM: plano/lead

Question 4

tx for CI

Answer 4

Primary – SRx
* Hyperopes –> + lenses can make XP worse, thus can do full or partial SRx & check if symptoms improve.
* Near ADD will not help.
* Myopes –> full SRx

Secondary – SRx + VT
* Best option for kids.

Tertiary – SRx + BI prism
* Best option for adults
* Rx to neutralize

Question 5

define divergence insufficiency (DI)

Answer 5

Insufficient divergence at distance that leads to a greater EP at distance than near (>8PD).

Question 6

symptoms of DI

Answer 6

• Asthenopia w/ distance task.
• Intermittent diplopia at distance.
• Symptoms worse towards the end of day.

Question 7

signs of DI?

Answer 7

Primary Test:
* CT: greater EP at distance than near (>8PD).
* NPC: normal
* NFV (NBI): normal
* NFV (DBI): reduced
* Vergence Fac: normal

Secondary Test:
* NRA: normal
* PRA: normal
* BAF: normal
* MAF: normal

Tertiary Test:
* BCC/MEM: normal

Question 8

tx for DI

Answer 8

Primary – SRx
* minus lenses may make it worse.
* Rx full plus

Secondary – SRx + prism
* BO prism – alleviate

Tertiary – SRx + VT
* Last tx – use BI prisms & minus lenses.

Question 9

what is pseudo-convergence insufficiency

Answer 9

A condition in which the primary problem is accommodative Insufficiency.

Question 10

signs for pseudo-convergence insufficiency

Answer 10

Primary Test:
* NPC: reduced (acc target) but normal w/ non-acc target.
* PFV (NBO): reduced
* PFV (DBO): normal
* Vergence Fac: difficulty w/ BO

Secondary Test:
* NRA: normal
* PRA: reduced
* BAF: reduced, hard w/ - lenses.
* MAF: reduced, hard w/ - lenses

Tertiary Test:
* BCC/MEM: large lag

Question 11

tx for pseudo-convergence insufficiency?

Answer 11

Primary – SRx
* Hyperopes: (+) lenses will help b/c it is an acc issue.
* Myopes: (-) lenses will make it difficult.

Secondary – SRx + near ADD
* Will help w/ accommodation.

Tertiary – SRx + VT
* High success

Prism will not help b/c it is not a convergence issue.