Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
convergence_insufficency [2025/02/15 17:39] Scott Larsonconvergence_insufficency [2025/06/14 04:44] (current) – [Convergence Insufficiency Symptom Survey] Scott Larson
Line 29: Line 29:
     * Before reaching the break point, the patient may note a point where the image blurs, the patient can no longer use fusional convergence and resorts to accommodative convergence which may improve convergence but causes a blurred image due to over-convergence      * Before reaching the break point, the patient may note a point where the image blurs, the patient can no longer use fusional convergence and resorts to accommodative convergence which may improve convergence but causes a blurred image due to over-convergence 
     * Reduce the base out prism until the patient recovers single vision, this is the **recovery point**.      * Reduce the base out prism until the patient recovers single vision, this is the **recovery point**. 
-    * if exotropia present ensure not worse XT in downgaze +    * if exotropia present ensure not worse XT in downgaze. 
-    * encouragement often improves convergence +    * Encouragement often improves convergence and should be provided to every patient. 
 +    * Testing convergence after testing divergence amplitudes will reduce convergence.
  
-== Convergence Amplitudes reported by Several Authors ==+=== Normal Convergence Amplitudes reported by Several Authors ===
  
 +^ Prism Diopters  ^ Parks (1976)  ^ Duane (1933)  ^ Fray (2017)  ^ Ferrari (2019)  ^
 +|  **Near**                                                                    |||||
 +| Break Point     | 20-25         | 38-51         | 35           | 45              |
 +| Recovery Point  | 18-22                                    | 40              |
 +|  **Distance**                                                                |||||
 +| Break Point     | 15            |               | 26           | 25              |
 +| Recovery Point  | 12            |                            | 20              |
  
-^ Prism Diopters  ^ Parks (1976)  ^ Duane (1933)  ^ Mein (1986)  ^ Fray (2017)  ^ Ferrari (2019)  ^ +====Convergence Amplitudes in Convergence Insufficiency==== 
-|  **Near**                                                                                         |||||                 | +Most studies would include patients with **≤ 15 PD break point**
-| Break Point     | 20-25         | 38-51         | 35-40        | 35            | 45              | +
-| Recovery Point  | 18-22                                    |               | 40              | +
-|  **Distance**                                                                                     |||||                 | +
-| Break Point     | 15            |                            | 26            | 25              | +
-| Recovery Point  | 12            |                            |               | 20              |+
  
 ====Other Signs of CI==== ====Other Signs of CI====
   * Low [[accommodative_convergence_to_accommodation_ratio|AC/A ratio]] of <2:1   * Low [[accommodative_convergence_to_accommodation_ratio|AC/A ratio]] of <2:1
-  * Reduced Positive fusional vergence <15PD+  * Esophoria larger at near than at distance
   * High CI symptom survey score of ≥16   * High CI symptom survey score of ≥16
  
 ====Convergence Insufficiency Symptom Survey==== ====Convergence Insufficiency Symptom Survey====
-Developed by the Convergence Insufficiency Treatment Trial Investigator Group 
-- Borsting EJ, Rouse MW, Mitchell GL, et al. Validity and reliability of the revised convergence insufficiency symptom survey in children aged 9 to 18 years. Optom Vis Sci. 2003;80(12):832-838. doi:10.1097/00006324-200312000-00014 
  
 +  - Do your eyes feel tired when reading or doing close work?
 +  - Do your eyes feel uncomfortable when reading or doing close work?
 +  - Do you have headaches when reading or doing close work?
 +  - Do you feel sleepy when reading or doing close work?
 +  - Do you lose concentration when reading or doing close work?
 +  - Do you have trouble remembering what you have read?
 +  - Do you have double vision when reading or doing close work?
 +  - Do you see the words move, jump, swim or appear to float on the page when reading or doing close work?
 +  - Do you feel like you read slowly?
 +  - Do your eyes ever hurt when reading or doing close work?
 +  - Do your eyes ever feel sore when reading or doing close work?
 +  - Do you feel a “pulling” feeling around your eyes when reading or doing close work?
 +  - Do you notice the words blurring or coming in and out of focus when reading or doing close work?
 +  - Do you lose your place while reading or doing close work?
 +  - Do you have to re-read the same line of words when reading?
 +
 +===Scoring===
 +  - Collect response to each question from one of the 5 possible responses: 
 +    - "Never" = 0 points
 +    - "Infrequently" = 1 point
 +    - "Sometimes" = 2 points
 +    - "Fairly Often" = 3 points
 +    - "Always" = 4 points
 +  - Tally points from each question- the total will be from 0-60 points
 +
 +===Analysis of Score===
 +If score is **≥ 16** CI is likely
 +  * Convergence Insufficiency mean= 30.8 ± 8.4
 +  * Normal mean = 8.4 ± 6.4 
 +  * Cut of value of **16** gives sensitivity of 95.7% and specificity of 87.5%
 +
 +<WRAP round info 50%>
 +[[https://eyefixer.org/convergence-insufficiency-symptom-score-calculator/|Go to the Convergence Insufficiency Symptom Score Calculator]]\\
 +</WRAP>
 +
 +
 +====Resources=====
 +  * [[http://www.oculist.net/downaton502/prof/ebook/duanes/pages/v1/v1c007.html| Marshall Parks. Vergences in Duanes Ophthalmology Chapter 7]]
 +  * [[https://1drv.ms/b/c/31d83ae8e55e0542/EZUo5zjeFwFNrit0qpD6i-MB_chEPfOxulf4tRmHQ6bvjQ?e=2rnC8e|Duane, A. The Convergence Index as a Measure of Converging Power. Trans Am Ophthalmology Soc. 1914;13(Pt3):851-8]]
 +  * [[https://1drv.ms/b/c/31d83ae8e55e0542/EQ4gyISNPhpKtOsBMqYytrsBwcms2Y6qoslJ2L9rFmq5bg?e=aXIxBb |Study of normative values of the fusional amplitudes of ocular convergence and divergence. Ferrari et al. eOftalmo 2019;5(4):167-72]]
 +  * [[https://1drv.ms/b/c/31d83ae8e55e0542/ETRfAZ9mtJZMuMACZAaAvbIBRfsTUw4oIfoFAkO84-6lxQ?e=dbyGr0 |Fusional Amplitudes: Developing Testing Standards. Fray K. Strabismus 2017;25(3):145-155]]
 +
 +{{tag>convergence}}