Archives for December 2016

Neuro-ophthalmology Questions of the Week: Anisocoria – Horner Syndrome & Cocaine

Questions:
1. How much anisocoria is necessary for the diagnosis of Horner’s syndrome to be made using cocaine drops?
a. 0.3 mm
b. 0.5 mm
c. 1.0 mm
d. 1.5 mm

2. What is the approximate mean odds ratio for the Cocaine pharmacologic test for Horner syndrome assuming a postcocaine anisocoria of at least 0.8mm?
a.   10:1
b.  100:1
c. 1,000:1
d. 10,000:1

3. Which of the following races may not dilate well with topical cocaine?
a. Asians
b. African Americans
c. Caucasians
d. Native Americans

4. Does the cocaine test for Horner syndrome result in a positive urinary test for cocaine?
a. Yes
b. No


Fig. 5.3. Right Horner’s Syndrome3

Neuro-ophthalmology Question of the Weeks: Anisocoria – Horner Syndrome Pharmacology

Question:
1.What is the effect of the following agents on the pupils in Horner Syndrome?
Cocaine
Hydroxyamphetamine
Apraclonidine

2. What is  the mechanism of action of each of these agent used to test Horner Syndrome?
Cocaine
Hydroxyamphetamine
Apraclonidine

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Neuro-ophthalmology Questions of the Week: Anisocoria – Horner Syndrome – Dilation Lag

Question:
How often is a dilation lag present in a patient with Horner Syndrome on the initial examination?
1. 100%
2.  85%
3.  70%
4.  50%

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Left-sided dilation lag in a 29-year-old man with Horner’s syndrome caused by a posterior mediastinal ganglioneuroma. Note that the degree of anisocoria is greater after 5 seconds in darkness (top) compared with findings after 15 seconds in darkness (bottom).  

Neuro-ophthalmology Question of the Week: Physiologic Anisocoria

Question: Which of the following are required for anisocoria to be physiologic?
1. Both pupils must react briskly to light.
2. There must be no dilation lag 5-15 seconds after room illumination is reduced to near darkness.
3. The patient must not be aware of the anisocoria.
4. The anisocoria is 1 mm or less.
5. The anisocoria must be present on different days.

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