Study on Ex-PRESS Implantation Combined With Phacoemulsification in Primary Angle-closure Glaucoma


Primary angle-closure glaucoma (PACG) is common, phacotrabeculectomy is associated with a significant risk of complications.The Ex-PRESS shunt was introduced as a modification to trabeculectomy, with the theoretical advantages of reduced complications.Our purpose is to perform a prospective study to evaluate the clinical outcomes and safety of the Ex-PRESS shunt with cataract surgery for PACG patients coexisting cataract.

Full Title of Study: “Prospective Study on Ex-PRESS Implantation Combined With Phacoemulsification in Primary Angle-closure Glaucoma”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: N/A
    • Intervention Model: Single Group Assignment
    • Primary Purpose: Treatment
    • Masking: None (Open Label)
  • Study Primary Completion Date: January 2018

Detailed Description

The Ex-PRESS is a miniature stainless steel glaucoma device, developed as an alternative to trabeculectomy mainly for patients with primary open-angle glaucoma.It has been proved to be as effective as trabeculectomy in a series of researches. However the early postoperative complication of Ex-PRESS implantation is less frequent compared with trabeculectomy. Ex-PRESS was designed initially for open angle glaucoma, gradually some scholars used it in refractory postpenetrating keratoplasty glaucoma and in vitrectomized glaucoma,which showed that Ex-PRESS shunt implantation was an effective procedure too. We analyzed the clinical efficacy and safety of combined phacoemulsification and Ex-PRESS implantation for PACG patients with cataract. Data was recorded before surgery and postoperatively at 1 week and 1, 3, 6, 12,18,24,30,36 months´╝îwhich included intraocular pressure (IOP), best corrected visual acuity (BCVA), number of medications, complications, corneal endothelial cell density and anterior segment optical coherence tomography(AS-OCT). Efficacy was assessed by IOP values and success rates. Complete success was determined by IOP between 5 and 21mmHg without medications.


  • Procedure: Ex-PRESS and phacoemulsification

Arms, Groups and Cohorts

  • Experimental: Ex-PRESS and phacoemulsification
    • A treatment session of PACG coexisting cataract treated with phacoemulsification combined with P50 Ex-PRESS miniature glaucoma device (Alcon Laboratories, Fort Worth, Texas, USA).

Clinical Trial Outcome Measures

Primary Measures

  • Intraocular pressure (IOP)
    • Time Frame: 36 months
    • In millimeters of mercury (mmHg), measured with the Goldmann applanation tonometer

Secondary Measures

  • Intraocular pressure (IOP)
    • Time Frame: 2 weeks, 1 month, 3 months, 6 months, 12 months,18 months, 24 months, 30 months,36 months.
    • In millimeters of mercury (mmHg), measured with the Goldmann applanation tonometer
  • Number of intraocular pressure lowering medications
    • Time Frame: 2 weeks, 1 month, 3 months, 6 months, 12 months,18 months, 24 months, 30 months,36 months.
    • Number of drops and oral medications used by the patient compared to baseline
  • Best corrected visual acuity (BCVA)
    • Time Frame: 2 weeks, 1 month, 3 months, 6 months, 12 months,18 months, 24 months, 30 months,36 months.
    • Number of lines reduction or improvement from baseline on Snellen acuity chart
  • Corneal endothelial cell density
    • Time Frame: 3 months
    • Use non-contact specular microscope to count the endothelial cell density (cells/mm2)
  • Anterior chamber distance(ACD)
    • Time Frame: 3 months
    • The distance from inner corneal surface to lens measured by AS-OCT
  • Angle opening distance(AOD500)
    • Time Frame: 3 months
    • Angle opening distance 500um from the scleral spur measured by AS-OCT

Participating in This Clinical Trial

Inclusion Criteria

  • The presence of PACG, angle peripheral anterior synechia (PAS) more than 180 degrees. – An indication for glaucoma filtering surgery based on uncontrolled IOP or progressive vision field defect despite antiglaucoma medications. – Mean vision field defect greater than 15dB. – The presence of a clinically significant decrease of visual acuity as a result of cataract, usually BCVA less than 0.6. Exclusion Criteria:

  • Patients unable to give informed consent. – Ocular infection or inflammation in the study eye in the 3 months prior to enrollment. – Intraocular surgery in the study eye in the 3 months prior to enrollment.

Gender Eligibility: All

Minimum Age: 18 Years

Maximum Age: N/A

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Wenzhou Medical University
  • Provider of Information About this Clinical Study
    • Principal Investigator: yin ying zhao, MD – Wenzhou Medical University
  • Overall Official(s)
    • Ai wu Fang, MD, Principal Investigator, Wenzhou Medical University
  • Overall Contact(s)
    • Li Nie, MD, +86-0571-86795965,

Citations Reporting on Results

Lai JS, Tham CC, Lam DS. Incisional surgery for angle closure glaucoma. Semin Ophthalmol. 2002 Jun;17(2):92-9. doi: 10.1076/soph.

Tham CC, Lai JS, Poon AS, Lai TY, Lam DS. Results of trabeculectomy with adjunctive intraoperative mitomycin C in Chinese patients with glaucoma. Ophthalmic Surg Lasers Imaging. 2006 Jan-Feb;37(1):33-41.

Tham CC, Kwong YY, Leung DY, Lam SW, Li FC, Chiu TY, Chan JC, Lam DS, Lai JS. Phacoemulsification versus combined phacotrabeculectomy in medically uncontrolled chronic angle closure glaucoma with cataracts. Ophthalmology. 2009 Apr;116(4):725-31, 731.e1-3. doi: 10.1016/j.ophtha.2008.12.054. Epub 2009 Feb 25.

Beltran-Agullo L, Trope GE, Jin Y, Wagschal LD, Jinapriya D, Buys YM. Comparison of visual recovery following ex-PRESS versus trabeculectomy: results of a prospective randomized controlled trial. J Glaucoma. 2015 Mar;24(3):181-6. doi: 10.1097/IJG.0b013e31829e1b68.

Gonzalez-Rodriguez JM, Trope GE, Drori-Wagschal L, Jinapriya D, Buys YM. Comparison of trabeculectomy versus Ex-PRESS: 3-year follow-up. Br J Ophthalmol. 2016 Sep;100(9):1269-73. doi: 10.1136/bjophthalmol-2015-307161. Epub 2015 Dec 16.

Netland PA, Sarkisian SR Jr, Moster MR, Ahmed II, Condon G, Salim S, Sherwood MB, Siegfried CJ. Randomized, prospective, comparative trial of EX-PRESS glaucoma filtration device versus trabeculectomy (XVT study). Am J Ophthalmol. 2014 Feb;157(2):433-440.e3. doi: 10.1016/j.ajo.2013.09.014. Epub 2013 Nov 7.

Zhang M, Li B, Sun Y. EX-PRESS and ahmed glaucoma valve in treatment of refractory glaucoma. Acta Ophthalmol. 2016 Aug;94(5):e382-3. doi: 10.1111/aos.12898. Epub 2015 Dec 8. No abstract available.

Liu B, Guo DD, Du XJ, Cong CY, Ma XH. Evaluation of Ex-PRESS implantation combined with phacoemulsification in primary angle-closure glaucoma. Medicine (Baltimore). 2016 Sep;95(36):e4613. doi: 10.1097/MD.0000000000004613.

Wagschal LD, Trope GE, Jinapriya D, Jin YP, Buys YM. Prospective Randomized Study Comparing Ex-PRESS to Trabeculectomy: 1-Year Results. J Glaucoma. 2015 Oct-Nov;24(8):624-9. doi: 10.1097/IJG.0000000000000029.

Marzette L, Herndon LW. A comparison of the Ex-PRESS mini glaucoma shunt with standard trabeculectomy in the surgical treatment of glaucoma. Ophthalmic Surg Lasers Imaging. 2011 Nov-Dec;42(6):453-9. doi: 10.3928/15428877-20111017-03.

Vetrugno M, Ferreri P, Sborgia C. Ex-PRESS miniature glaucoma device in vitrectomized eyes. Eur J Ophthalmol. 2010 Sep-Oct;20(5):945-7. doi: 10.1177/112067211002000521.

Kanner EM, Netland PA, Sarkisian SR Jr, Du H. Ex-PRESS miniature glaucoma device implanted under a scleral flap alone or combined with phacoemulsification cataract surgery. J Glaucoma. 2009 Aug;18(6):488-91. doi: 10.1097/IJG.0b013e31818fb44e.

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