Diurnal Fluctuations of Intraocular Pressure in EX-Press Valve Blebs in Glaucoma Patients

GLAUCOMA Clinical Trial

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT02665884
• Other study ID #: 0085-15-HYMC
• Status: Not yet recruiting
• Phase: N/A
• First received: November 29, 2015
• Last updated: January 24, 2016
• Start date: February 2016
• Est. completion date: February 2017

Study information

• Verified date: November 2015
• Source: Hillel Yaffe Medical Center
• Contact: Yuval Cohen, MD., PhD
• Phone: 0586904951
• Email: dr.yuvalcohen[@]gmail.com
• Is FDA regulated: No
• Health authority: Israel: Ministry of Health
• Study type: Observational

Clinical Trial Summary

Diurnal fluctuations of intraocular pressure in EX-Press Valve Blebs in Glaucoma Patients

Intraocular pressure (IOP) reduction is the mainstay of glaucoma management. (1) Open-angle glaucoma (OAG) is generally managed by decreasing the intraocular pressure (IOP) to a level that the physician believes will prevent further glaucomatous damage. However, in a significant proportion of patients, the visual fields continue to deteriorate in spite of office pressures within the range of normal values (8). It has been suggested that the progressive damage in some cases could be caused by peaks of IOP or diurnal IOP variability not detected by tonometry during office hours. It is possible that certain drugs or surgical interventions are more effective than others in dampening these fluctuations. The purpose of our study is to compare the diurnal IOP fluctuations in glaucoma patients treated with medications or Ex-press filtration surgery.

Description:

Diurnal fluctuations of intraocular pressure in EX-Press Valve Blebs in Glaucoma Patients

Department of Ophthalmology, Hillel-Yaffe Medical Center, affiliated with the Bruce Rappaport School of Medicine, The Technion, Haifa, Israel

Introduction:

Intraocular pressure (IOP) reduction is the mainstay of glaucoma management. (1) Medication alone is sometimes not sufficient to reduce excessively high IOP, and pharmaceutical intolerance may develop or damage can occur to the optic nerve, warranting surgical intervention. (2) The filtering bleb is considered to be the cornerstone of IOP control after glaucoma filtration surgery drainage device implantation. (3) It enables the flow of the aqueous humor from the anterior chamber to the subconjunctiva, episclera, sclera and choroid, thereby lowering the IOP. (4-6) Filtration and drainage devices, such as the EX-Press device (Alcon Laboratories, Fort Worth, Texas, USA), offer a surgical alternative to glaucoma medical therapy. (7) Open-angle glaucoma (OAG) is generally managed by decreasing the intraocular pressure (IOP) to a level that the physician believes will prevent further glaucomatous damage. However, in a significant proportion of patients, the visual fields continue to deteriorate in spite of office pressures within the range of normal values (8). It has been suggested that the progressive damage in some cases could be caused by peaks of IOP or diurnal IOP variability not detected by tonometry during office hours. (9, 10) In another study, Asrani et al. (11) showed that IOP fluctuations are an independent risk factor in patients with glaucoma and as such may need to be treated specifically. It is possible that certain drugs or surgical interventions are more effective than others in dampening these fluctuations. The purpose of our study is to compare the diurnal IOP fluctuations in glaucoma patients treated with medications or Ex-press filtration surgery.

Materials and Methods The study will include 20 open-angle glaucoma (OAG) patients underwent Ex-Press filtration surgery, and 20 OAG patients treated with medications alone. All patients will have 12 IOP measurements with 2 hours interval, starting at 10 AM until 10 AM of the following morning.

ICARE® PRO tonometer (Icare Finland Oy, Espoo, Finland) will be used for the measurement of IOP. The rebound motion of its light weighted probe will be recorded during contact of the probe with the cornea. (12, 13) The rate of deceleration of the probe is a function of IOP. The ICARE® PRO has a built-in inclination sensor that allows downward measurement of the eye in the supine position as well as in the normal upright sitting position. ICARE® PRO allows for measurement of IOP in the seated and supine positions. During IOP recording, patients will be supine or upright, and the tip of the probe will be applied perpendicular to the cornea. Two markers engraved on the piston of the probe indicated its ideal positioning. The reliability of the measurement is displayed on the ICARE® PRO tonometer screen and guided our measurements.

Fluctuations in IOP will be compared between the Ex-press filtration surgery eye and the fellow (intra-group comparison). Inter-group comparison of IOP fluctuation will be performed between the Ex-press filtration surgery eye and medically treated eye of different patients.

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 40
• Est. completion date: February 2017
• Est. primary completion date: February 2017
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 30 Years to 80 Years

Eligibility

Inclusion Criteria: .

• Glaucoma patients that underwent EX-PRESS surgery

Exclusion Criteria:

• Angle closure glaucoma

• Neovascular glaucoma

• High refractive error

Study Design

Observational Model: Cohort, Time Perspective: Prospective

Related Conditions & MeSH terms

• GLAUCOMA

Intervention

Other:
• Intraocular Pressure Measurement
Diurnal fluctuations of intraocular pressure will be measured and compared

Locations

Country	Name	City	State
Israel	Hillel Yaffe Medical Center	Hadera

Sponsors (1)

Lead Sponsor	Collaborator
Hillel Yaffe Medical Center

Country where clinical trial is conducted

Israel, 

References & Publications (13)

Asrani S, Zeimer R, Wilensky J, Gieser D, Vitale S, Lindenmuth K. Large diurnal fluctuations in intraocular pressure are an independent risk factor in patients with glaucoma. J Glaucoma. 2000 Apr;9(2):134-42. — View Citation

DeBry PW, Perkins TW, Heatley G, Kaufman P, Brumback LC. Incidence of late-onset bleb-related complications following trabeculectomy with mitomycin. Arch Ophthalmol. 2002 Mar;120(3):297-300. — View Citation

DRANCE SM. DIURNAL VARIATION OF INTRAOCULAR PRESSURE IN TREATED GLAUCOMA. SIGNIFICANCE IN PATIENTS WITH CHRONIC SIMPLE GLAUCOMA. Arch Ophthalmol. 1963 Sep;70:302-11. — View Citation

Hu CY, Matsuo H, Tomita G, Suzuki Y, Araie M, Shirato S, Tanaka S. Clinical characteristics and leakage of functioning blebs after trabeculectomy with mitomycin-C in primary glaucoma patients. Ophthalmology. 2003 Feb;110(2):345-52. — View Citation

Iliev ME, Goldblum D, Katsoulis K, Amstutz C, Frueh B. Comparison of rebound tonometry with Goldmann applanation tonometry and correlation with central corneal thickness. Br J Ophthalmol. 2006 Jul;90(7):833-5. Epub 2006 May 3. — View Citation

Kidd MN, O'Connor M. Progression of field loss after trabeculectomy: a five-year follow-up. Br J Ophthalmol. 1985 Nov;69(11):827-31. — View Citation

Levene RZ. Glaucoma filtering surgery: factors that determine pressure control. Ophthalmic Surg. 1984 Jun;15(6):475-83. — View Citation

Martinez-de-la-Casa JM, Garcia-Feijoo J, Castillo A, Garcia-Sanchez J. Reproducibility and clinical evaluation of rebound tonometry. Invest Ophthalmol Vis Sci. 2005 Dec;46(12):4578-80. — View Citation

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.e — View Citation

Picht G, Grehn F. Classification of filtering blebs in trabeculectomy: biomicroscopy and functionality. Curr Opin Ophthalmol. 1998 Apr;9(2):2-8. Review. — View Citation

The Advanced Glaucoma Intervention Study (AGIS): 7. The relationship between control of intraocular pressure and visual field deterioration.The AGIS Investigators. Am J Ophthalmol. 2000 Oct;130(4):429-40. — View Citation

Watson PG. When to operate on open angle glaucoma. Eye (Lond). 1987;1 ( Pt 1):51-4. — View Citation

Zeimer RC, Wilensky JT, Gieser DK, Viana MA. Association between intraocular pressure peaks and progression of visual field loss. Ophthalmology. 1991 Jan;98(1):64-9. — View Citation

* Note: There are 13 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Comparison of diurnal fluctuations of intraocular pressure	Comparison of diurnal fluctuations of intraocular pressure in glaucoma patients with and without EX-Press valve surgery	One year	No