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

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Mr Andre Ismail


Contact details

Eye Unit
Southampton General Hospital
Tremona Road
SO16 6YD
United Kingdom
+44 (0)7880551176

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title


Study hypothesis

To determine whether there is a 'significant difference' in the measurement of eye pressures in patients having had a penetrating keratoplasty (corneal transplant), by using two established methods of measurement - firstly 'dynamic contour tonometry' and secondly 'Goldmann applanation tonometry'? A 'significant difference' will be measured as greater than 2mm Hg pressure between the two methods.

Ethics approval

Not provided at time of registration

Study design

Randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type

Not Specified

Patient information sheet


Eye Diseases


Patients who have undergone corneal transplant surgery will be contacted from a database of all patients who have undergone this surgery at Southampton Eye Unit. Patients will be asked to attend the eye clinic for one visit only. Assessments will be conducted by two of the investigators - A.Ismail (Specialist registrar Ophthalmology), and M.Lamont (Senior House Officer Ophthalmology). Each patient will have their intraocular pressure and corneal thickness measured. These measurements are routinely performed in the eye clinic and are not unduly intrusive or burdensome. In order to compare pressure measurements by DCT and GAT, the following is performed: 1) It is randomised whether DCT or GAT measurement occurs first. 2) It is also randomised which investigator will perform the measurement first. 3) Each investigator measures the patients intraocular pressure in the eye being studied alternately by GAT and DCT 3 times in succession. 4) The second investigator is blind to the readings, and performs the same measurements successively. 5) In total, the patient will have their eye pressure measured 12 times in succession. 6) The corneal thickness of the eye will be measured by ultrasound pachymetry. On average, measurement of the eye pressure by either of the methods takes roughly 5 seconds, and is completely painless. Disposable tonometer heads will be used for both instruments and between patients. There are no known complications for either technique for the patient, aside from possible inaccuracy of reading. The measurement of corneal thickness by ultrasound pachymetry is almost an identical procedure from the patients point of view. The ultrasound probe is sterilised between patients, as is normal clinical practice. Once again there are no known complications of this investigation to the patient. Once these readings have been taken, the patient is discharged from the eye clinic, back to their usual follow up. Informal discussions with patients that have been seen in the clinic with corneal transplants have shown a positive response to research in this area, and a willingness to participate in the small added length of time to their clinic visit.

Intervention type



Not Specified

Drug names

Primary outcome measures

The difference in intraocular pressure measurements between DCT and GAT for each patient. 2mm Hg will be seen as significant.

Secondary outcome measures

Not provided at time of registration

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

Not provided at time of registration

Participant type


Age group

Not Specified


Not Specified

Target number of participants

10 patients. No controls - comparative study.

Participant exclusion criteria

Not provided at time of registration

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Eye Unit
SO16 6YD
United Kingdom

Sponsor information


Record Provided by the NHSTCT Register - 2006 Update - Department of Health

Sponsor details

The Department of Health
Richmond House
79 Whitehall
United Kingdom
+44 (0)20 7307 2622

Sponsor type




Funder type


Funder name

Southampton University Hospitals NHS Trust (UK) NHS R&D Support Funding

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

2007 results in

Publication citations

  1. Results

    Ismail AR, Lamont M, Perera S, Khan-Lim D, Mehta R, Macleod JD, Anderson DF, Comparison of IOP measurement using GAT and DCT in patients with penetrating keratoplasties., Br J Ophthalmol, 2007, 91, 7, 980-981, doi: 10.1136/bjo.2006.099564.

Additional files

Editorial Notes