J Korean Ophthalmol Soc.  2016 Sep;57(9):1400-1406. 10.3341/jkos.2016.57.9.1400.

Iris-trabecular Contact Index Change after Cataract Surgery in Acute Angle Closure Glaucoma

• Park JH
• Kim HS
• Lee TH
• Lee KH

• KMID: 2351870
• DOI: http://doi.org/10.3341/jkos.2016.57.9.1400

Abstract

PURPOSE
To evaluate the change of iris-trabecular contact index (ITC index) after cataract surgery in acute angle closure glaucoma.
METHODS
Twelve patients (17 eyes) who had a history of acute angle closure glaucoma underwent swept source optical coherence tomography before and after cataract surgery. Correlations between lens vault (LV), ITC index and intraocular pressure (IOP), anterior chamber depth (ACD), anterior chamber volume (ACV), and angle parameters were analyzed before and after cataract surgery.
RESULTS
IOP (p = 0.007), ACD (p < 0.001), ACV (p < 0.001), angle parameters (p = 0.001), and ITC index (p = 0.012) were improved after cataract surgery. ITC index decreased from 88.42 ± 23.59% to 48.91 ± 35.13% after cataract surgery (p = 0.012). There was no correlation between LV and ACD (p = 0.075), ACV (p = 0.864), angle parameter (p = 0.112-0.707), or ITC index (p = 0.288) before cataract surgery. The correlations between ITC index and IOP (p = 0.021), ACD (p = 0.002), ACV (p < 0.001), and angle parameter (p = 0.001-0.030) were statistically significant before surgery but not statistically significant (p = 0.223/0.206/0.761/ 0.096-0.819) after surgery.
CONCLUSIONS
ITC index significantly improved after cataract surgery, but part of angle closure was not resolved in some cases of acute angle closure glaucoma.

Keyword

Acute angle closure glaucoma; Cataract surgery; Iris-trabecular contact index; Lens vault

MeSH Terms

Anterior Chamber
Cataract*
Glaucoma, Angle-Closure*
Humans
Intraocular Pressure
Tomography, Optical Coherence

Figure

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  Figure 1. Swept source optical coherence tomography image illustrating anterior chamber depth (ACD) and lens vault (LV). White arrows indicate the scleral spur.

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  Figure 2. Cross-section image of angle structure illustrating angle parameters. (A) Angle opening distance at 500 μ m from scleral spur (AOD500) and trabecular-iris angle 500 (TIA500). (B) Trabecular-iris surface area 500 (TISA500) is expressed by dot printed and angle recess area 500 (ARA500) is expressed by a hatched box.

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  Figure 3. Swept source optical coherence tomography image illustrating a single frame of anterior chamber. (A) The red colored “x” are the scleral spurs (SS) and the “+” are the iris-trabecular contact end points (EP). (B) Iris-trabecular con-tract (ITC) chart with blue area representing the amount and the distribution of iris-trabecular contact. Red line is the consecutive line of the scleral spur and the green line is the consecutive line of end point. (C) Iris-trabecular contact graph with X axis representing the degree of the angle, Y axis repre-senting iris-trabecular contact. “+” means the contact with iris and trabecular meshwork and “-” means non-contact between the two structures.

Reference

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