1. IOP control and corneal endothelial cell density changes
P-FS-316
IOP control and corneal endothelial cell density changes
after Baerveldt glaucoma implant fixed at the ciliary sulcus
Sotaro Mori1※, Mari Sakamoto1 , Kaori Ueda1 , Yukako Inoue1 , Takuji Kurimoto1, Akiyasu Kanamori1 , Yuko Yamada1 , Makoto Nakamura1
1 ) Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine
* address:
Purpose
There is increasing popularity to perform Baerveldt glaucoma implant (BGI) for the treatment of refractory glaucoma.
However, the placement of BGI tube in the anterior chamber is known to increase a chance of corneal endothelial damages,
while the ciliary body-fixed type BGI requires vitrectomy. The placement of BGI tube at the ciliary sulcus may be used
as an option to reduce the risk for corneal endothelial damage.
To test this issue, we investigated the IOP control and corneal endothelial density (ECD) after the ciliary sulcus-fixed BGI.
Methods
This study is a prospective interventional non-randomized non-comparative case series, which comprised twenty eight eyes of 27 consecutive patients that underwent the ciliary sulcus-fixed BGI and were followed up for at least 6 months from December 2013 to November Primary outcome measures were postoperative intraocular pressure (IOP), best-corrected log MAR visual acuity (VA), and ECD.
Surgical Technique
A 350mm2 BGI was placed underneath extraocular muscles. Scleral tunnel was made by 26G needle insertion
at 1.5mm posterior to the limbus and parallel to the iris. The tunnel was broadened by the second insertion of 21G needle. An ILM forceps was inserted into the anterior chamber through the corneal side port, which was infixed into the pre-inserted 21G needle and pulled out of the scleral tunnel. Then, the BGI tube was grasped by the ILM forceps and dragged into the posterior chamber in front of the IOL.
Figure 1. IOP and glaucoma drug score changes
Results
Table 1. Patient Characteristics (mean ±SD otherwise specified)
Friedman test: P<0.0001
No of eyes 27
Age at Surgery (Yrs)
55.7±22.3
Gender (% men)
59.3
Eye (% right eye)
55.6
Combined cataract surgery (%)
22.2
Glaucoma type (n (%))
Primary angle-closure glaucoma,
13 (48.1)
Secondary glaucoma
9 (33.3)
Exfoliation glaucoma
1 (3.7)
Childhood glaucoma
4 (14.8)
Preoperative IOP (mmHg)
30.1±8.6
Preoperative glaucoma drug score
4.5±1.1
Preoperative logMAR visual acuity
0.64±0.53
No. of Previous glaucoma operation
2.4±1.4
Preoperative endothelial cell density (cells/mm2)
1669.9±812.2
Figure 2. Visual acuity and corneal endothelial cell density changes (cells/mm2)
Table 2. Success rate and Adverse event (n (%))
Overall outcome
Success (=IOP 5～21mmHg w/o reoperation)
22 (81.5)
Failure
5 (18.5)
Adverse Event
Hyphema
3 (11.1)
Choroidal detachment
4 (14.8)
Macular edema
Vitreous hemorrhage
2 (7.4)
Tube corneal touch
Reoperation
logMAR VA： P=0.047
(Friedman test)
Discussion
The magnitude and rate of IOP reduction in eyes with sulcus-fixed BGI in the present study were similar to those in eyes with anterior chamber or vitreous cavity-fixed BGI1,2). There are not more frequent adverse event compared to fixed with other BGI1,2).
In comparison, the endothelial loss, on average, was insignificant in the present study, while previous studies demonstrated long tube shunt surgery cause loss of ECD3,4). As the distance between the tube and cornea is reportedly a risk factor of ECD loss 4), two cases that showed significant reduction of ECD in the present study also underwent the tube-corneal touch due to the very shallow anterior chamber.
Conclusion
The ciliary sulcus-fixed BGI may be a promising option both to achieve good IOP control and avoid corneal endothelial damages in eyes with refractory glaucoma.
References
Saheb H, et al. Am J Ophthalmol. 2014; 157:
Budenz DL, et al. Am J Ophthalmol. 2017; 163: 75-82
Chihara E et al. Jpn J Ophthalmol. 2012;56:119-27
Tan, AN, et al. Acta Ophthalmol. 2017; 95: 91-96
Conflict of interest (COI) : No potential COI to disclose.