Modified Trabeculectomy With an ESST Versus Conventional SST for Management of Primary Open Angle Glaucoma

Primary Open-angle Glaucoma Clinical Trial

— POAG  

Official title:

Modified Trabeculectomy With an Extended Subscleral Tunnel Versus Conventional Trabeculectomy for Management of Primary Open Angle Glaucoma (POAG)

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03480711
• Other study ID #: N-38-2018
• Status: Completed
• Phase: N/A
• Start date: July 10, 2018
• Est. completion date: March 2, 2019

Study information

• Verified date: July 2022
• Source: Cairo University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

• To evaluate prospectively the surgical outcome in terms of intraocular pressure control, potential advantages, disadvantages, success rate, complications and bleb morphology of this modified trabeculectomy with an extended subscleral tunnel (ESST) in comparison to the conventional subscleral trabeculectomy (SST) in management of uncontrolled primary open angle glaucoma.

• This study will recruit 40 eyes of (40) candidate patients with primary open angle glaucoma (POAG) who are indicated for surgery.

• The candidate patients will be recruited into 2 equal comparative groups. In group (A) 20 eyes (20 patients) who will undergo conventional (SST) with intraoperative mitomycin C (MMC) (0.03%) and group (B); 20 eyes of 20 patients will undergo trabeculectomy with an ESST also with intraoperative adjunctive MMC (0.03%).

Description:

• Different surgical procedures were developed and the principle behind them was to establish a fistula between the anterior chamber and the subconjunctival space to permit the aqueous humour to exit the eye.

• Subscleral trabeculectomy has remained the most commonly performed glaucoma surgery to which the newer operations are compared.Although this procedure is very effective in reducing intraocular pressure (IOP) immediately, surgical failure has often been observed over time due to fibrosis of the surgical site and resultant non-filtering bleb. -Improvement of the complication profile and the efficacy of glaucoma filtering surgery is still a major concern for glaucoma surgeons.Therefore, several modifications, combinations, and new techniques of subscleral trabeculectomy have been described.

• In the current study, a fornix-based conjunctival flap will be fashioned in an attempt to encourage more posterior drainage. In this modified trabeculectomy technique, an additional small perpendicular strip of sclera is removed extending from the AC to 2 mm beyond the edge of the scleral flap thus creating an extended subscleral trabeculectomy facilitating aqueous passage into the posterior subconjunctival space.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: March 2, 2019
• Est. primary completion date: February 28, 2019
• Accepts healthy volunteers: No
• Gender: All
• Age group: 40 Years to 70 Years

Eligibility

Inclusion Criteria:

• Patients with POAG aged from (40- 70) years who are candidate for glaucoma surgery with BCVA = 3/60 to be able to perform visual field testing.

• Non- compliant patients to the medical treatment willing for follow-up visits for at least 6 months post-operatively .

Exclusion Criteria:

• Congenital, traumatic, neovascular, uveitic glaucomas or cases with angle closure glaucoma (ACG) associated with shallow AC.

• Undergoing simultaneous cataract surgery.

• Previous vitreo-retinal surgery including vitrectomy and buckling surgery.

• Other pre-existing ocular cicatrizing diseases.

• Corneal abnormality that precluded reliable applanation tonometry.

Related Conditions & MeSH terms

• Glaucoma
• Glaucoma, Open-Angle
• Primary Open-angle Glaucoma

Intervention

Procedure:
• SST in group (A)
group (A) single surgeon, using retrobulbar anaesthesia with 2% lidocaine, will be performed in all surgeries. Following insertion of a lid speculum, a 10/0 silk bridle suture is inserted at superior limbus if required. In group (A) a conjunctival incision is made at the limbus to create a fornix-based conjunctival flap. A half thickness scleral flap (4 × 4 mm) are created and dissected into the clear cornea. A cellulose microsponge soaked in 0.3 mg/ml MMC solution (Mitomycin-C) is applied to the under surface of the scleral flap over a wide posterior area for 2 ml
• trabeculectomy with ESST in group (B)
group (B), another longitudinal scleral groove will be created in the center of the deep scleral bed area measured about 1.5 × 6 mm.In both groups, standard trabeculectomy of equal size (two bites aside) is created by a Kelly punch ( 1 mm)

Locations

Country	Name	City	State
Egypt	Faculty of medicind	Cairo

Sponsors (2)

Lead Sponsor	Collaborator
Rehab mahmoud abdelhamid mohamed	Cairo University

Country where clinical trial is conducted

Egypt, 

References & Publications (2)

El Sayyad F, Belmekki M, Helal M, Khalil M, El-Hamzawey H, Hisham M. Simultaneous subconjunctival and subscleral mitomycin-C application in trabeculectomy. Ophthalmology. 2000 Feb;107(2):298-301; discussion 302. — View Citation

Nuijts RM, Vernimmen RC, Webers CA. Mitomycin C primary trabeculectomy in primary glaucoma of white patients. J Glaucoma. 1997 Oct;6(5):293-7. Review. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	change from baseline intraocular pressure at first day postoperative	mmHg	day one postoperatively
Primary	change from baseline intraocular pressure at 4 weeks	mmHg	, 4 weeks.
Primary	change from baseline intraocular pressure at 6 weeks Ultrasound bimicroscopy (UBM)	mm Hg	6 weeks post-operatively.
Primary	change from baseline intraocular pressure at 3 months	mmHg	3 months postoperatively
Primary	change from baseline intraocular pressure at 6 months	mmHg	6 months postoperatively
Secondary	change from baseline best corrected visual acuity (BCVA) at 6 months	logarithm of minimal angle of resolution (log MAR)	at the end of 6 months
Secondary	extent of filtering bleb area by ultrasound of bio-microscopy (UBM)	width, depth and height of filtering bleb area in millimeter	6 weeks postoperatively