Alphabet Patterns Flashcards
What is a physiological V pattern defined as?
A physiological tendency for divergence on elevation. To be physiological we’d be looking at a <15 difference from depression to elevation
What is a pathological V pattern defined as?
> 15PD difference from depression to elevation
What is a pathological A pattern defined as?
> 10PD from elevation to depression
What are the alphabet patterns?
V, A, X, Y, Inverted Y & Diamond
What is this pattern?
5BO Elevation
15BO pp
30BO Depression
V Eso
What is this pattern?
30BO Elevation
15BO pp
5BO Depression
A Eso
What is this pattern?
5BI Elevation
15BI pp
30BI Depression
A Exo
What is this pattern?
30BI Elevation
15BI pp
5BI Depression
V Exo
What is this pattern?
35BI Elevation
25BI pp
10BI Depression
V Exo
What is this pattern?
10BO Elevation
25BO pp
35BO Depression
V Eso
What is this pattern?
10BI Elevation
25BI pp
35BI Depression
A Exo
What is this pattern?
35BO Elevation
25BO pp
10BO Depression
A Eso
What is the prevalence of A or V patterns in horizontal strabismus?
12 - 50%
V 2x as common as A
A Exo more common than A Eso
What is Antimongoloid?
Downward slanting palpebral fissures
What pattern is someone with Antimongoloid likely to have?
More likely to have a V pattern
What is Mongoloid?
Upward slating palpebral fissures
What pattern is someone with Mongoloid likely to have?
More likely to have an A pattern
What orbital anomalies often display A and V-patterns?
Craniosynostosis (abnormally shaped skulls due to premature fusion of sagittal and frontal sutures at birth), such as Crouzon, Apert and Pfeiffer syndromes and plagiocephaly, often display A- and V-patterns owing to orbital anomalies
What pattern is associated with an ET with IO o/a?
V Pattern
What pattern is associated with an XT with IO o/a?
V Pattern
What pattern is associated with an XT with SO o/a?
A pattern
What pattern is associated with an ET with SO o/a?
A pattern
(as more divergence looking down)
What vertically acting muscle weakness is a V Eso associated with?
SO weakness
What vertically acting muscle weakness is a V Eso associated with? What happens in depression and in elevation?
SO weakness
In depression: –> less abduction + o/a of IR = increased adduction
In elevation: o/a of IO gives relatively more abduction + u/a of SR = less adduction