1. Selective laser trabeculoplasty in Korean eyes with medically uncontrolled pseudoexfoliation glaucoma
Su Chan Lee1, Jung Hyun Lee1, Mi Jin Kim2, Hye Jin Chung1, Yun Suk Chung1, Jin Young Choi1, Mi Jeung Kim1
1Department of Ophthalmology, HanGil Eye Hospital, Incheon, Korea
2Department of Ophthalmology, Kim's Eye Hospital, Seoul, Korea
Introduction
Results
Selective laser trabeculoplasty (SLT)
Widely used as a primary or adjunctive therapy for lowering intraocular pressure (IOP).
IOP reduction (≥12 months) in pseudoexfoliative glaucoma (PXFG) ranged from 11% to 32%.1
Few studies reported the efficacy of SLT in medically uncontrolled PXFG.2 However, there has been no report in Korean populations.
IOP lowering efficacy of SLT might be affected by ethnicity.3
Comparisons of baseline characteristics between 1year success and failure group
Baseline characteristics of PXFG eyes
PXFG eyes (n=23)
Age (years)
72.2 ± 8.8
Sex ; Male : Female (No.)
12 : 11
IOP (mmHg)
27.7 ± 4.9
Number of medications
3.6 ± 0.7
Phakic : Pseudophakic (No.)
11 : 12
VF index
MD (dB)
± 9.7
PSD (dB)
7.7 ± 4.1
Success (n=12)
Failure (n=11)
P-value
Age (years)
74.4 ± 8.7
69.8 ± 8.6
0.260*
Sex ; Male : Female
(No.)
6 : 6
6 : 5
1.000†
IOP (mmHg)
26.4 ± 5.1
29.1 ± 4.5
0.151*
Number of medications
3.6 ± 0.7
0.833*
Phakic : Pseudophakic
5 : 6
VF index
MD (dB)
-18.0 ± 11.2
-18.3 ± 8.2
0.786*
PSD (dB)
6.5 ± 4.6
8.5 ± 3.2
0.169*
VF, visual field; MD, mean deviation; PSD, pattern standard deviation
Purpose
*Mann-Whitney test; † Fisher’s exact test
To assess the efficacy of SLT in Korean eyes with medically uncontrolled PXFG
Survival Analysis of medically uncontrolled PXFG eyes (n=23)
No significant differences in the baseline characteristics
between two groups (all P > 0.05)
Correlation analysis between IOP decrement and VF in 1 year success group
Patients and Methods
IOP decrement (mmHg)
Rho (P-value*)
vs MD
vs PSD
1 day
8.4 ±10.7
(>0.05)
(>0.05)
1 week
10.8 ± 5.4
0.153 (>0.05)
(>0.05)
1 months
9.7 ± 6.1
0.232 (>0.05)
(>0.05)
3 months
12.0 ± 6.4
0.728 (0.007)
(>0.05)
6 months
10.4 ± 4.6
0.376 (>0.05)
0.359 (>0.05)
1 year
10.5 ± 6.0
0.439 (>0.05)
0.130 (>0.05)
Retrospective Observational study
Patients
23 eyes of 23 PXFG patients who had undergone first-time SLT
: followed up ≥ 12 months after SLT
: enrolled from
Glaucoma Clinic of HanGil Eye Hospital and Kim’s Eye Hospital
from August 2013 to March 2016
Inclusion criteria
: (1) Age ≥ 18 years old
(2) Open angle on gonioscopic exam
(3) Pseudoexfoliation
(4) IOP ≥ 21 mmHg despite of topical maximum
tolerated medical treatment
Exclusion criteria
(1) History of uveitis, trauma and other ocular diseases
(2) History of laser or surgical therapy for glaucoma
SLT procedure
: Q-switched frequency-doubled 532nM Nd:YAG laser
started at 0.6 mJ and increased by 0.2 mJ until cavitation bubbles were visible ( <1.2 mJ )
360° treated with contiguous laser spots
topical medication adjustments at the physician's discretion
Ophthalmologic examinations
including visual acuity, fundoscopy, slit-lamp biomicroscopy and Goldmann applanation tonometry
baseline & followed at 1 hour, 1 day, 1 week, 1, 3, 6 months and 1 year after SLT
IOP spike : defined as IOP rise of ≥ 10 mmHg than baseline in 1 day after SLT
Kaplan-Meier survival analysis
Criteria for treatment success / failure
Success : ≥ 20% IOP reduction from baseline without additional anti glaucomatous interventions (systemic medications, laser, and incisional glaucoma surgery)
Failure
< 20% IOP reduction from baseline at 2 consecutive
follow ups or
(2) additional anti glaucomatous interventions regardless of
the degree of IOP reduction
Fig.1. Kaplan-Meier survival curve of 23 PXFG eyes
* Spearman correlation analysis
During 1 year follow up, IOP decrements at each time
intervals were not associated with the severity of
glaucoma except at 3 months follow-up in success group.
Cumulative probability of failure after SLT at 1year was 47.8% (11 eyes)
< 20% IOP reduction from baseline in 9 eyes (39.1%)
Additional interventions despite of ≥ 20% IOP reduction from baseline in 2 eyes (8.7%)
IOP decrement of phakic and pseudophakic eyes in 1year success group
No significant differences in the IOP decrement
between phakic and pseudophakic eyes at all follow-up
points (all P > 0.05)
Mean IOP following SLT in PXFG eyes
Adverse events
IOP spike : 2 eyes (8.7%) → Filtering surgery
No other significant adverse events except
transient conjunctival hyperemia
Number available*
Mean IOP (mmHg)
P-value†
Pre-SLT
Post-SLT
Baseline 23 -
27.7 ± 4.9
1 day 22
27.2 ± 4.5
20.7 ± 9.5
0.005
1 week 21
27.1 ± 4.5
15.8 ± 3.4
<0.001
1 months 18
27.1 ± 4.9
17.3 ± 3.6
3 months
15.5 ± 2.8
6 months 17
27.0 ± 5.0
17.0 ± 4.2
1 year 12
26.4 ± 5.1
15.8 ± 2.6
0.002
Conclusions
About half (52.2%) of medically uncontrolled Korean PXFG eyes showed overall 1-year IOP
lowering efficacy (≥ 20% IOP reduction from baseline without additional interventions).
45% of failure was observed in the early phase (within 3 months). ; This suggests that prognosis is not worse if IOP is controlled for more than 3 months.
IOP lowering efficacy of SLT does not seem to be affected by the severity of glaucoma and prior cataract surgery.
No significant adverse events except 2 eyes (8.7%) of IOP spike.
→ SLT might be considered as one of the treatment modality in medically refractory PXFG eyes, that is effective in some part.
* Included in the analysis until failure, then removed from subsequent follow-up
† Wilcoxon signed–rank test for analyzing changes in IOP from pre-SLT values
References
Wong MO, et al. Systematic review and meta-analysis
on the efficacy of selective laser trabeculoplasty in
open-angle glaucoma. Surv Ophthalmol. 2015;60:36-50.
2. Goldenfeld M, et al. Selective laser trabeculoplasty in
uncontrolled pseudoexfoliation glaucoma. Ophthalmic
Surg Lasers Imaging. 2011;42:
3. Goosen E, et al. Racial Differences in Selective Laser
Trabeculoplasty Efficacy. J Curr Glaucoma Pract. 2017
;11:22-7
Fig. 2. Change of IOP in 1 year success group (n=12)
* Wilcoxon signed–rank test: all P < 0.05
Success at 1year group (n=12)
Mean IOP reduction : 10.5 ± 6.0 mmHg
(39.8 % reduction from pre-SLT value)
Number of medications was decreased but it was not statistically significant. (3.6 ± 0.7 → 3.4 ± 0.7, Wilcoxon signed–rank test : p = 0.317)
• Conflicts of Interest : We have no financial interests or
relationships to disclose. •