Abstract
Purpose
To assess the prevalence of A-V pattern strabismus and evaluate the clinical characteristics, surgical methods and outcomes.
Methods
Among 825 patients who underwent horizontal strabismus surgery, the records of patients with A-V pattern strabismus were reviewed retrospectively. The prevalence and clinical characteristics of patients with A-V pattern strabismus were assessed and the surgical methods and outcomes of A-V pattern strabismus were evaluated.
Results
Among 825 patients with horizontal strabismus surgery, 113 (13.7%) patients had A-V pattern. V exotropia was the most common (65.5%) and A esotropia was the least common (7.1%) pattern. A +1.9 inferior oblique overaction in 92.8% of the V-pattern patients and a +1.5 superior oblique overaction in 70.0% of the A pattern patients was found. Among the 113 patients, 64.6% patients underwent oblique muscle surgery and 35.4% patients underwent vertical transposition of horizontal muscle. Vertical incomitance was significantly reduced after surgery in all types of A-V pattern strabismus ( p<0.05) with a surgical success rate of 96.5%.
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![]() | Figure 1.Distribution of A-V pattern strabismus among 113 patients; * XT=exotropia; † ET=esotropia. |
Table 1.
Distribution of A-V pattern strabismus in different reports in Korea
Table 2.
Relative frequency of A and V pattern strabismus among 113 patients
V pattern (%) | A pattern (%) | Total (%) | |
---|---|---|---|
Exotropia | 74 (65.5) | 22 (19.5) | 96 (85.0) |
Esotropia | 9 (8.0) | 8 (7.1) | 17 (15.1) |
Total | 83 (73.5) | 30 (26.5) | 113 (100) |
Table 3.
Characteristics of patients with A-V pattern strabismus
V-exotropia | A-exotropia | V-esotropia | A-esotropia | ||
---|---|---|---|---|---|
Age (years) | ) | 15.4±11.2 | 17.4±14.0 | 19.2±19.1 | 19.0±17.1 |
Sex (M/F∗) | 33/41 | 7/13 | 4/5 | 6/2 | |
BCVA† | OD‡ | 0.9±0.2 | 0.9±0.3 | 0.8±0.2 | 0.7±0.2 |
OS | 0.9±0.2 | 1.0±0.1 | 0.7±0.4 | 0.9±0.1 | |
R.E§ | OD | -0.7±1.8 | -0.3±1.7 | 0.2±2.8 | -0.5±2.0 |
OS | -0.8±2.2 | -0.3±1.3 | 0.7±3.0 | -0.4±1.7 | |
Amblyopia | 7/64 (10.9%) | 4/13 (30.8%) | 3/9 (33.3%) | 2/8 (25.0%) | |
Titmus∏ | 364.7±845.7 | 869.5±1193.5 | 548.9±948.9 | 1166.7±1594.8 | |
AHP# | 19/64 (29.7%) | 6/13 (46.1%) | 2/9 (22.2%) | 2/8 (25.0%) |
Table 4.
Preoperative and postoperative measurements in A-V pattern strabismus
Table 5.
Frequency and grade of oblique muscle dysfunction in A-V pattern strabismus
Oblique muscle dysfunction (%) | Grade of oblique muscle dysfunction | |
---|---|---|
V-exotropia | 68/74 (91.8) | +2.0±1.2 (IOOA∗) |
A-exotropia | 17/22 (77.3) | +1.9±1.5 (SOOA†) |
V-esotropia | 9/9 (100.0) | +1.7±1.0 (IOOA) |
A-esotropia | 4/8 (50.0) | +1.0±1.1 (SOOA) |
Table 6.
Surgical methods for A-V pattern strabismus
Table 7.
Collapse of pattern after surgery for A-V pattern strabismus
Table 8.
Amount of decrease in A or V pattern after surgery
Amount of decrease in A or V pattern | |||
---|---|---|---|
Oblique muscle surgery | Vertical transposition of horizontal rectus muscle | P-value† | |
V-exotropia | 17.5±6.6∗ | 17.0±4.8 | 0.128 |
A-exotropia | 12.9±7.1 | 11.8±3.4 | 0.400 |
V-esotropia | 16.9±5.9 | 15.8±3.9 | 0.815 |
A-esotropia | 12.0±0.1 | 12.7±6.1 | 0.889 |
Total | 14.8±7.0 | 14.3±4.5 | 0.558 |