Comparison of posterior capsule opacification after two different surgical methods of cataract extraction

ISRCTN ISRCTN88815601
DOI https://doi.org/10.1186/ISRCTN88815601
Secondary identifying numbers N/A
Submission date
08/10/2007
Registration date
22/10/2007
Last edited
14/04/2008
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Eye Diseases
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Not provided at time of registration

Contact information

Dr Jana Nekolová
Scientific

University Hospital in Hradec Králové
Department of Ophthalmology
Sokolská 581
Hradec Králové
50005
Czech Republic

Phone +420 60 410 6256
Email jani.nekolova@seznam.cz

Study information

Study designProspective, single-centre, randomised controlled study.
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Not specified
Study typePrevention
Scientific title
Study objectivesPosterior capsule opacification (PCO) is the most frequent complication of crystalline lens extracapsular extraction. When PCO reaches the central part of IOL (intraocular lens), it can induce a decrease in visual acuity after cataract surgery. Many preventive factors and many surgical techniques decreasing secondary cataract development exist but there is still no extended procedure of its complete eradication. AquaLase is a new crystalline lens removal technology using the method of liquefaction of lens material by the pulses of warmed balanced salt fluid produced just inside the aspiration port of the tip. As the AquaLase tip is made of smooth rounded-bevel polymer rather than metal, the risk of capsule tears is reduced making this method more capsule friendly. Thus the lens epithelial cells (LECs) removal from the capsule bag is much easier which may be preventive for the PCO occurrence and progress. Subjective EPCO 2000 and objective OSCA are systems for computer PCO assessment.

The study is aimed at comparison of PCO extent after AquaLase and NeoSoniX cataract removal modalities using two types of software for PCO quantification, and at the comparison of these two different methods for PCO measurement. Better results in PCO for AquaLase are expected. While using this device, it is difficult to rupture the posterior capsule. Several studies have shown that the technology may have applications in polishing the capsule through mechanical washing of the lens epithelial cells (LEC) from the capsule bag with the fluid pulses. The reduction of LECs has been shown to help prevent PCO. The OSCA is a newly presented system of PCO computer assessment, evolved from previous systems. It is based on location-sensitive entropy based texture analysis of digital images. It was presented by Aslam in 2006. The OSCA results are compared to EPCO 2000 outcomes in this study. The EPCO 2000 is a computer-assisted system of PCO morphological assessment which incorporates planimetric and grading assessment. No correlation between OSCA and EPCO 2000 outcomes is expected.
Ethics approval(s)Ethics Committee at University Hospital in Hradec Králové, Sokolská 581, 50005 Hradec Králové, Czech republic. Date of approval: 04/10/2007
Health condition(s) or problem(s) studiedCataracts
InterventionThe AquaLase is used in the right eye and NeoSoniX in the left eye of each patient. The same IOL (Alcon AcrySof® Single Piece Intraocular Lens) is implanted in all eyes.

Examination is carried out at 1, 2, 3 and 5 years after surgery. Digital retroillumination photographs of pseudophakic anterior segments, after attaining maximal pupil dilatation are obtained using a CSO Epsilon Lyrae photo slit lamp. Exact focusing on the IOL and posterior capsule is also carried out. The images are computer analyzed with the EPCO 2000 and OSCA software. Best corrected visual acuity (BCVA) is measured using Snellen optotypes pre- and postoperatively. The "Nd: YAG" laser capsulotomy incidence is evaluated.
Intervention typeOther
Primary outcome measureThe following will be measured at 1, 2, 3 and 5 years after surgery:
1. EPCO index for minimal, mild, moderate and severe opacities and total EPCO index for PCO under entire IOL optic (score 0 = no opacities, 4 = maximal opacities)
2. OSCA score. The possible range is from 0 (no PCO) to approximately 15 (practical expected maximum). Typical OSCA values for images with very little or no PCO is around 0.5. Values for patients that are deemed to warrant laser capsulotomy is typically around 4 - 5.
3. Best corrected visual acuity measured using Snellen optotypes at 6 metres distance
Secondary outcome measuresThe "Nd:YAG" laser capsulotomy rate at 1, 2, 3 and 5 years after surgery. This shows how many capsulotomies are needed for treatment of PCO-induced decrease of BCVA.
Overall study start date11/11/2004
Completion date20/10/2012

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participants75
Key inclusion criteria1. Bilateral non-brunescent cataract (according to the Buratto classification - a cataract grade less than 5)
2. Both eyes with cataract with similar density grade
3. No other severe ocular pathology potentially affecting visual acuity (patients with mild age-related macular degeneration [ARMD] were not excluded)
4. Age 40 or older
5. Both males and females
6. Written informed consent to surgery and willing to participate in the study
7. Good compliance
Key exclusion criteria1. Brunescent cataract
2. Severe ocular pathology potentially affecting visual acuity
3. Unable to achieve good artificial mydriasis
4. No informed consent
Date of first enrolment11/11/2004
Date of final enrolment20/10/2012

Locations

Countries of recruitment

  • Czech Republic

Study participating centre

University Hospital in Hradec Králové
Hradec Králové
50005
Czech Republic

Sponsor information

University Hospital in Hradec Králové (Czech Republic)
University/education

c/o Dr Jana Nekolová
Department of Ophthalmology
Sokolská 581
Hradec Králové
50005
Czech Republic

Phone +420 49 583 3395
Email jani.nekolova@seznam.cz
Website http://www.fnhk.cz
ROR logo "ROR" https://ror.org/04wckhb82

Funders

Funder type

University/education

The trial is mainly funded internally by the University Hospital in Hradec Kralove. The trial is also supported by research project grant from the Ministry of Health of Czech Republic (ref: MZO 00179906).

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article Results 01/03/2008 Yes No