Posterior capsular opacification 9 years after cataract surgery with a hydrophobic acrylic and a hydrophilic acrylic intraocular lenses
| ISRCTN | ISRCTN46164776 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN46164776 |
| Secondary identifying numbers | N/A |
- Submission date
- 30/09/2015
- Registration date
- 30/09/2015
- Last edited
- 01/10/2015
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Eye Diseases
Plain English Summary
Background and study aims
Cataracts are cloudy areas on the lens of the eye. They can appear for a number of reasons, however they are most common in older people, developing over a long period of time (senile cataract). The lens sits near the front of the eye, and plays an important role in vision. When cataracts cause the lens to become clouded, it can prevent light from reaching the back of the eye (retina) to form an image that can be interpreted by the brain. When this happens, vision becomes blurred and distorted, and can eventually lead to blindness. Cataract surgery involves removing the affected lens and replacing it with a clear artificial one (intraocular lens). There are several different types of intraocular lens that may be used, namely hydrophilic (dissolvable) or hydrophobic (non-dissolvable). This type of surgery is usually very successful, helping to restore vision within a matter of weeks. Posterior capsule opacification (PCO) is a common complication of cataract surgery. When the cataract is removed, a thin, clear membrane is left which holds the intraocular lens in place (lens capsule). When PCO occurs, the lens capsule thickens, causing vision to become cloudy. In most cases, PCO is treated with a painless procedure, where a laser (neodymium: yttrium-aluminium-garnet (Nd:YAG) laser capsulotomy) is used to make an opening in the back of the lens capsule so that light can again reach the retina. Recent evidence suggests that many more cases of PCO develop in the long-run, and the type of intraocular lens used may be linked to its development. The aim of this study is to find out whether hydrophilic or hydrophobic intraocular lens are more prone to developing PCO 9 years after cataract surgery.
Who can participate?
Adults between 60 and 90 years of age who have senile cataract.
What does the study involve?
Participants are randomly allocated into two groups who have either a hydrophilic intraocular lens or a hydrophobic intraocular lens implanted when their cataracts are removed. After nine years, patients in both groups attend a follow up appointment, in which images are taken of their eyes to look for PCO. If any patients have had Nd-YAG laser treatment for PCO, this is noted at the time of the appointment.
What are the possible benefits and risks of participating?
Not provided at time of registration
Where is the study run from?
St. Erik Eye Hospital (Sweden)
When is the study starting and how long is it expected to run for?
November 2001 to December 2012
Who is funding the study?
1. Karolinska Institute (Sweden)
2. Stockholms County Council (Sweden)
3. Eye Foundation (Sweden)
Who is the main contact?
Mr Anthony Chang
Contact information
Scientific
Polhemsgatan 50
Stockholm
11282
Sweden
Study information
| Study design | Single-centre prospective randomised parallel trial |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised parallel trial |
| Study setting(s) | Hospital |
| Study type | Prevention |
| Scientific title | Posterior capsular opacification 9 years after phacoemulsification with the hydrophobic AcrySof SA60AT and hydrophilic BL27 intraocular lenses |
| Study hypothesis | A hydrophilic acrylic intraocular lens develops more posterior capsule opacification and has a lower survival rate without Nd:YAG laser capsulotomy than a hydrophobic acrylic intraocular lens 9 years after cataract surgery. |
| Ethics approval(s) | Regional ethical review board in Stockholm (Sweden), 07/10/2011, ref: Dnr 2011/1319 |
| Condition | Cataract |
| Intervention | The patients were randomized to one of the two intraocular lenses (IOLs) by selection of an unmarked, opaque envelope from among 120 envelopes containing the name of either the hydrophobic SA60AT IOL or the hydrophilic BL27 IOL. The surgical procedure was the same for all patients and included implantation of an IOL. One group received a hydrophilic IOL and the other group a hydrophobic IOL. After 9 years, patients attend a follow up appointment where the development of posterior capsule opacification in the two groups is observed and compared. Images of posterior capsule opacification will be obtained and computer software used in order to analyse, calculate and compare posterior capsule opacification between the 2 groups. If earlier Nd:YAG laser capsulotomy was conducted, it was noted at this stage. |
| Intervention type | |
| Primary outcome measure | Survival rates without Nd:YAG capsulotomy in hydrophobic and hydrophilic IOL determined from data collected 9 years after surgery. |
| Secondary outcome measures | Percentage area affected by PCO and PCO severity determined 9 years after surgery using POCOman computer software. |
| Overall study start date | 05/11/2001 |
| Overall study end date | 30/05/2012 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Sex | Both |
| Target number of participants | 120 |
| Participant inclusion criteria | 1. Aged 60 to 90 years 2. Presence of senile cataract |
| Participant exclusion criteria | 1. Dilated pupil smaller than 6.0 mm 2. Ocular trauma 3. Traumatic cataract 4. Pseudoexfoliation syndrome, 5. Glaucoma 6. Exfoliation syndrome 7. Corneal pathologies 8. Diabetes mellitus 9. Uveitis 10. Moderate and advanced age-related macular degeneration 11. Those receiving preoperative oral steroid therapy 12. Those who underwent a previous intraocular surgery |
| Recruitment start date | 22/05/2002 |
| Recruitment end date | 18/03/2004 |
Locations
Countries of recruitment
- Sweden
Study participating centre
Stockholm
11282
Sweden
Sponsor information
Charity
Ögonfonden / Synfrämjandets Forskningsfond
c/o Fatima Pedrosa-Domellöf
Oftalmiatrik, Umeå universitet
Umeå
90185
Sweden
| Phone | +46 90 785 13 40 |
|---|---|
| info@ogonfonden.se | |
| Website | http://www.ogonfonden.se/kontakt/ |
Government
Hantverkargatan 45
Stockholm
10422
Sweden
| Phone | +46 70 737 44 66 |
|---|---|
| landstinget@sll.se | |
| Website | http://www.sll.se/om-landstinget/Information-in-English1/Research/ |
University/education
Solnavägen 1
Stockholm
17177
Sweden
| Phone | +46 8 524 800 00 |
|---|---|
| info@ki.se | |
| Website | http://ki.se/en/about/startpage |
Funders
Funder type
Hospital/treatment centre
No information available
Government organisation / Local government
- Alternative name(s)
- Stockholm County Council
- Location
- Sweden
No information available
Results and Publications
| Intention to publish date | 31/12/2015 |
|---|---|
| Individual participant data (IPD) Intention to share | No |
| IPD sharing plan summary | Stored in repository |
| Publication and dissemination plan | Publication in a peer reviewed journal. |
| IPD sharing plan |
