Abstract
Purpose
To evaluate intrableb morphology and function after trabeculectomy using anterior segment optical coherence tomography (AS-OCT)
Methods
Twenty-eight post-trabeculectomy eyes from patients with primary open-angle glaucoma were examined using AS-OCT. Intrableb structures, including bleb wall thickness, subconjunctival fluid, suprascleral fluid and the route under the scleral flap, were measured at the center of the bleb using AS-OCT and were classified according to their slit-lamp appearance. Blebs were classified as successful (IOP≤18 mmHg without ocular hypotensive medication) and failed (IOP>18 mmHg or use of ocular hypertensive medication.) in order to compare parameters between the two groups.
Results
The blebs were classified as either diffuse filtering (n=17), cystic (n=5), encapsulated (n=3) or flattened (n=3) according to slit lamp appearance and were correlated with AS-OCT images. Blebs were classified as successful and failed in order to compare parameters between the two groups. Significant differences were observed between the two groups in regard to sub-conjunctival fluid space (p=0.0004). No significant differences were observed in bleb wall thickness (p=0.098), suprascleral fluid space (p=0.87) or the route under the scleral flap (p=0.196).
References
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Table 1.
| Diffuse functioning bleb (n=17) | Cystic bleb (n=5) | Encapsulated bleb (n=3) | Flattened bleb (n=3) |
---|---|---|---|---|
Age (y) | 50.76±13.04 | 59.00±16.29 | 52.33±14.15 | 65.00±19.97 |
Sex (M/F) | 14/3 | 2/3 | 3/0 | 2/1 |
Postop (months) | 44.82±34.17 | 8.4±2.70 | 35±42.79 | 103±63.24 |
IOP (mmHg) | 11.29±4.62 | 11.60±2.70 | 22.00±7.00 | 25.00±7.00 |
Successful/Failed* (n) | 8/9 | 3/2 | 0/3 | 0/3 |
Bleb wall thickness(mm) | 0.14±0.04 | 0.11±0.05 | 0.43±0.06 | 0.25±0.09 |
Subconjunctival fluid (mm) | 0.48±0.34 | 0.73±0.39 | 0 | 0.02±0.02 |
Suprascleral space (mm) | 0.21±0.13 | 0.14±0.05 | 2.20±0.36 | 0.08±0.02 |
Route under scleral flap (+/-) | 17/0 | 3/2 | 2/1 | 0/3 |
Table 2.
| Successful (n=12) | Failed (n=16) | p-value |
---|---|---|---|
Age (y) | 51.75±17.04 | 55.50±12.57 | 0.51 |
Sex (M/F) | 7/5 | 14/2 | 0.1 |
Postop (months) | 23.41±23.94 | 58.56±46.64 | 0.115 |
IOP (mmHg) | 9.42±3.73 | 17.37±6.77 | 0.001* |
Bleb wall thickness (mm) | 0.13±0.05 | 0.22±0.13 | 0.09 |
Subconjunctival fluid (mm) | 0.70±0.37 | 0.21±0.24 | 0.004* |
Suprascleral space (mm) | 0.24±0.16 | 0.53±0.84 | 0.87 |
Route under scleral flap (+/-) | 11/1 | 11/5 | 0.2 |
Table 3.
| Successful (n=12) | Failed (n=10) | p-value |
---|---|---|---|
Bleb type (n) | | | |
Diffuse functioning bleb | 8 | 9 | |
Cystic bleb | 4 | 1 | |
Age (y) | 51.75±17.05 | 53.60±9.63 | 0.76 |
Sex (M/F) | 7/5 | 9/1 | 0.09 |
Postop (months) | 23.42±23.94 | 52.30±37.98 | 0.06 |
IOP (mmHg) | 9.42±3.73 | 13.70±3.62 | 0.01* |
Bleb wall thickness (mm) | 0.13±0.05 | 0.14±0.04 | 0.73 |
Subconjunctival fluid (mm) | 0.70±0.37 | 0.33±0.22 | 0.01* |
Suprascleral space (mm) | 0.24±0.16 | 0.16±0.04 | 0.12 |
Route under scleral flap (+/-) | 11/1 | 9/1 | 0.89 |