1. Early results of a Pilot Study
Randomised Controlled Trial of Phaco-Endocycloplasty vs Phaco-Trabeculectomy in medically controlled and uncontrolled Primary Angle Closure Disease:
Early results of a Pilot Study
Vanita Pathak-Ray FRCS (Ed), FRCOphth (Lon)1
Swati Badkare MS2, Siddharth Dikshit DNB2, Nikhil Choudhari DNB2
1Director Glaucoma Services, Centre for Sight, Hyderabad, India
2VST Centre for Glaucoma Care, L V Prasad Eye Institute, Hyderabad, India.
Background
Cataract and glaucoma frequently co-exist
The lens – due to its relatively anterior position, thickness, increased lens rise - plays an important role in the pathogenesis of the spectrum of Primary Angle Closure Glaucoma (PACG) and its removal is advocated early, rather than late in the disease
When glaucoma is uncontrolled medically or shows progression in the presence of cataract, current gold standard of Phaco-trabeculectomy (P-T) is a widely practiced procedure
However, PT is not without pitfalls - it is associated with increased inflammation (a cause for failure) and unique vision-threatening complications like hypotony and bleb related complications, including life-long risk of bleb-associated-endophthalmitis (BAE)
Thus it becomes imperative to find newer, safer but equally efficacious solutions for PACG - one such modality is combining endocycloplasty (ECPL) with phaco (P-E)
A pilot study of 10 eyes by the lead author yielded encouraging results (Table 1): at median 18 months follow-up, P-E significantly reduced IOP, need for *AGM, with successful early visual rehabilitation
Results
42 eyes of 39 patients; 22 females
22 eyes in P-E group; 2 excluded as laser not per protocol. 20 eyes in P-T
Median f/u 6 months in both groups
Table 2: Pre-operative characteristics
Phaco-Trab
n=20
Phaco-ECPL
p value
Age, Median (IQR)
59 (13)
65 (12)
0.23
IOP mmHg, Median (IQR)
17 (13)
20 (15.5)
0.76
Uncontrolled IOP
n=10
0.25
AGM, Median (IQR)
3 (2)
3 (1)
0.93
LogMAR BCVA, Median (IQR)
0.4 (0.3)
0.3 (0.25)
0.9
Post-LPI occludable
n=14
0.28
Synaechial closure, Median quads, IQR
0 (2)
0 (1.5)
0.62
Lens rise in microns, Median IQR
630 (340)
690 (330)
0.5
VFI %
66 (13.5)
36 (47.5)
0.14
Table 3: Post-operative characteristics
Table 1: Results of a pilot study of Phaco-ECPL in Angle Closure Disease
Phaco-Trab
n=20
Phaco-ECPL
p value
IOP mm Hg, Median (IQR)
16 (6)
15 (4.25)
0.8
AGM, Median (IQR)
0.9
LogMAR BCVA, Median (IQR)
0.1 (0.25)
0.7
Parameter
Pre Phaco-ECPL
Post Phaco-ECPL p
Median IOP mmHg (IQR; range)
20 ( 5.5; 11-46)
15.5 (5.75; 12-40)
<0.01
Median *AGM
3 (IQR 1.75)
Median LogMAR BCVA
0.55 (IQR 0.4)
0 (IQR 0.075)
*AGM – Anti-glaucoma medication
Purpose
To investigate the efficacy and safety of endocycloplasty compared with trabeculectomy, when these are combined with phacoemulsification in medically controlled and uncontrolled Primary Angle Closure Disease, post laser peripheral iridotomy (LPI)
Methods
Study design: Prospective, interventional, comparative randomised control trial
Inclusion criteria:
Subjects over the age of 30 years with
Primary Angle Closure disease (Primary Angle Closure, PAC and Primary Angle Closure Glaucoma, PACG), post LPI, with visually significant cataract
Exclusion criteria: Ocular surface infection
Previous intra-ocular surgery
Secondary angle closure glaucoma One-eyed subjects
Depression of any paracentral point on 10-2 HVF to 0 dB
Computer generated randomized sequence of either study procedure (P-E or P-T)) for all indications of combined surgery
Uncontrolled IOP
Controlled IOP on 3 or more AGM
Involvement of fixation on 10-2 HVF
Subjects intolerant to or unable to afford AGM also underwent randomisation.
Table 4 : Complications and interventions
Complications
Phaco-Trab
Intervention
Phaco-ECPL
Intra-op
AM n=1
IZHV n=1
ZD n=1
ECR n=1
Post-op
Fibrinous uveitis n=3
Yag to membrane n=1
Fibrinous uveitis n=5
Repeat LPI n=2
Hyphaema n=1 -
Leak n=4
BCL in all
Encysted bleb n=2
AM n=1
Yag hyaloidotomy
Failure n=1
Bleb revision n=1
Trab n=1 .
Complication n=13 in P-T and n=7 in P-E (p=0.5)
No patient lost vision in either group
Discussion
Primary Outcome Measure:
Intra-ocular Pressure (IOP)
Secondary Outcome Measure/s:
Best-corrected LogMAR visual acuity (BCVA)
Anti-Glaucoma medication (AGM)
Complications
Our study is unique as studies on ECP hitherto have mainly concentrated in open angle or refractory glaucomas with moderate success only.
The ability of P-E in IOP control in angle closure appears to be via a two-pronged mechanism
ECPL helps to anatomically modify the angle recess, as seen in intra-operative ASOCT – more than phaco alone; change in angle recess is also seen in post-operative UBM (1st prize winning video at WGC, Helsinki 2017)
Photocoagulative effect on ciliary processes
Advantages:
Low risk of hypotony as only 2-3 quadrants treated, post-op quieter eyes
With swifter recovery, speedier visual rehabilitation,
Adds only 5-10 mins to phaco
Most importantly it does not preclude future trabeculectomy as conjunctiva is not compromised.
Surgical Procedures
Phaco-ECPL (P-E)
Performed in the OR under regional anaesthesia
Clear corneal phaco and intra-ocular lens implant (PCIOL) inserted
Endoscope was introduced through the phaco wound, with delivery of laser under direct vision after creating space in sulcus with cohesive viscoelastic
Laser was aimed at the ‘tail’ of the ciliary process, as a modification of the ECP process called endocycloplasty (ECPL) Figure 1
Laser power was determined by end-point of whitening and shrinkage of ciliary body for degrees; ‘pops’ were strictly avoided (starting point 500 mw X 2000 ms)
At the end of the procedure, viscoelastic washed and sub-conjunctival steroid administered (Dexamethasone 2mg)
Phaco-Trab (P-T)
Performed in the OR under regional anaesthesia
Phaco and trabeculectomy done through separate sites – both incisions superior
Trab – conjunctival incision supero-nasal in the right eye (Figure 3 below) and supero-temporal in the left.
Sponge application of Mitomycin C (MMC) 0.4 mg/ml used for 2 minutes after rectangular scleral flap was raised
Phaco via a clear corneal supero-temporal wound in the right eye Figure 2 (or supero-nasal in the left eye)
Post PCIOL insertion, phaco wound sutured with 10/0 nylon
At the end of the procedure, sub-conjunctival steroid was administered (Dexamethasone 2mg)
Conclusion
This pilot study of P-E vs. P-T suggests that in the short term P-E is as efficacious as P-T in angle closure glaucoma, without the incumbent bleb-related complications.
Further follow-up is required to ascertain whether this is sustained.
References
Uram M. Combined phacoemulsification, endoscopic ciliary process photocoagulation, and intraocular lens implantation in glaucoma management. Ophthalmic Surg. 1995; 26:
Ahmed IK, et al. Endoscopic cycloplasty in angle closure glaucoma secondary to plateau iris. Poster presented at: AGS Annual Meeting; March 5-8, 2009, San Diego, CA.
Hollander DA et al Management of plateau iris syndrome with cataract extraction and endoscopic cyclophotocoagulation. Exp Eye Res 2017 May;158:
Francis BA et al Endoscopic Cycloplasty (ECPL) and Lens Extraction in the Treatment of Severe Plateau Iris Syndrome Mar;25(3):e128-33
Figure 1 : laser beam (red dot) aimed at the tail of the ciliary process
Figure 2 : Separate site phaco-trab
P-FS-332
Financial Support: None
Conflict of Interest: None relevant