Clinical trial NCT03480711: Modified Trabeculectomy With an ESST Versus Conventional SST for Management of Primary Open Angle Glaucoma
Official title: Modified Trabeculectomy With an Extended Subscleral Tunnel Versus Conventional Trabeculectomy for Management of Primary Open Angle Glaucoma (POAG)
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Primary Open-angle Glaucoma
Keywords: subscleral trabeculectomy
extended subscleral tunnel
mitomycinC
Lead sponsor: Cairo University
Sponsor class: OTHER
Collaborators: name: Cairo University
First posted: 2018-03-29
Enrollment: 40
Sex: ALL
Minimum age (years): 40
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Randomized non-controlled comparative prospective interventional study
Primary purpose: TREATMENT

Brief 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%).

Detailed 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.

Eligibility criteria: 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.

Primary outcomes:
measure: change from baseline intraocular pressure at first day postoperative
timeFrame: day one postoperatively
measure: change from baseline intraocular pressure at 4 weeks
timeFrame: , 4 weeks.
measure: change from baseline intraocular pressure at 6 weeks Ultrasound bimicroscopy (UBM)
timeFrame: 6 weeks post-operatively.
measure: change from baseline intraocular pressure at 3 months
timeFrame: 3 months postoperatively
measure: change from baseline intraocular pressure at 6 months
timeFrame: 6 months postoperatively
Secondary outcomes:
measure: change from baseline best corrected visual acuity (BCVA) at 6 months
timeFrame: at the end of 6 months
measure: extent of filtering bleb area by ultrasound of bio-microscopy (UBM)
timeFrame: 6 weeks postoperatively
Other outcomes:
Locations:
city: Cairo
country: Egypt
facility: Faculty of medicind
Study officials:
affiliation: Associate Professor of Ophthalmology , Cairo university
name: Riham S Allam, MD, FRCS GL
role: PRINCIPAL_INVESTIGATOR
affiliation: Professor of Ophthalmology , Cairo university
name: Karim A Raafat, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: lecturer of Ophthalmology , Cairo university
name: Rehab M Mohamed, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: 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. doi: 10.1016/s0161-6420(99)00097-4.
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.