Condition category
Eye Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
Cataracts occur when the inner lens of the eye clouds, causing vision problems. Glaucoma (high pressure inside the eye) can also cause vision problems. Cataracts can occur alongside glaucoma but also may cause glaucoma, be a result of glaucoma (high pressure inside the eye). For those who have glaucoma and cataracts, there are a number of options on how to treat them. Trabeculectomy is usually done to help lower the internal pressure of the eye by making a surgical incision through a small thin trap door in the eye to drain the fluid. However, this may have an impact on cataract surgery and requires certain management of treatment and medication. One of the main treatments for cataracts is called phacoemulsification, which is a surgical procedure that using a device to break up the cloud lens, and then inserts an intraocular lens (IOL) (an artificial lens) using an incision. Incisions can be made in different locations. The aim of this study is to compare two different corneal (the front clear layer of the eye) incisions of uneventful phacoemulsification and IOL on eyes that have undergone previous successful surgery for glaucoma.

Who can participate?
Adults aged 18 or older who previously had a success trabeculectomy for glaucoma who need cataract surgery

What does the study involve?
Participants are randomly allocated to one of two groups. Those in the first group undergo phacoemulsification with a temporal (near the front) corneal incision. Those in the second group undergo phacoemulsification with a superior corneal incision (done under the eye lid). Participants in each group are compared for their intraocular pressure changes (pressure in the eye), any blebs (part of the eye ballooning and protruding from the top of the eyeball) and any needed medication for glaucoma.

What are the possible benefits and risks of participating?
Participants may benefit from improvements in vision. There are small risks associated with phacoemulsification such as infections, retinal detachment, flashing, double vision or swelling in the eye.

Where is the study run from?
Sohag University (Egypt)

When is the study starting and how long is it expected to run for?
October 2014 to January 2016.

Who is funding the study?
Investigator initiated and funded (Egypt)

Who is the main contact?
Dr Mohamed Anbar

Trial website

Contact information



Primary contact

Dr Mohamed Anbar


Contact details

Sohag University
Sohag University Road
Naser City

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Effect of different incision sites of phacoemulsification on trabeculectomy bleb function: Prospective case-control study


Study hypothesis

The aim of this study was to compare superior and temporal clear corneal incisions of uneventful phacoemulsification and in-the-bag intraocular lens implantation on intraocular pressure control and the bleb morphology in eyes that have undergone previous successful trabeculectomy.

Ethics approval

Not provided at time of registration.

Study design

Prospective single centre randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type

Not Specified

Patient information sheet

No participant information sheet available


Cataract and glaucoma


Participants who previously undergone trabeculectomy without antimetabolites are consecutively allocated (1:1) to one of two groups.

Group 1 (Temporal group): Participants in this group undergo phacoemulsification with a temporal corneal incision.

Group 2 (Superior group): Participants in this group undergo phacoemulsification with a superior corneal incision.

Comparisons between the two groups are performed after one year of follow-up regarding intraocular pressure changes, bleb morphology score using the Wuerzburg bleb classification score and any added glaucoma medications.

Intervention type



Drug names

Primary outcome measure

1. Intraocular pressure changes is measured using the Goldman tonometer … at day one, one week, one month, three months, six months, and one year postoperatively
2. Bleb morphology score is measured using the Wuerzburg bleb classification score at day one, one week, one month, three months, six months, and one year postoperatively
3. Additional glaucoma medications are measured using patient's records up to one year postoperatively

Secondary outcome measures

There are no secondary outcome measures.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Previous successful trabeculectomy not augmented by antimetabolites and had well-controlled IOP
2. Well-functioning bleb, no preoperative glaucoma medications
3. A visually significant cataract before phacoemulsification
4. Aged 18 and older

Participant type


Age group




Target number of participants


Total final enrolment


Participant exclusion criteria

1. Patients with primary angle closure glaucoma,
2. Secondary glaucoma
3. Associated eye diseases
4. Preoperative antimetabolite use
5. Posterior capsule rupture and/or vitreous loss during phacoemulsification

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Sohag University Hospital
Sohag University

Sponsor information


Sohag University

Sponsor details

Sohag University Road
Naser City

Sponsor type

Hospital/treatment centre



Funder type

Not defined

Funder name

Investigator initiated and funded

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Publication and dissemination plan and intention to publish date planned publication in a high-impact peer reviewed journal.

IPD sharing statement:
The datasets generated during and/or analysed during the current study are/will be available upon request from (

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

2017 results in (added 26/11/2020)

Publication citations

Additional files

Editorial Notes

26/11/2020: The following changes were made to the trial record: 1. Publication reference added. 2. The total final enrolment was added.