INCISIONS: Impact of Incision Size and Architecture on Wound Stability and Astigmatism in Cataract Surgery: an Exploratory Study

Sponsor

Vienna Institute for Research in Ocular Surgery (Other)

Overall Status

Completed

CT.gov ID

NCT01778998

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

3.6

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

One of the most recent advances in cataract surgery is microincisional phacoemulsification (MICS). Through small incisions of 2.0 mm and less the lens material is emulsified either bimanually or with a thin single coaxial hand-piece. The possible advantages are lower induced corneal astigmatism1, 2, possibly a lower incidence of infection due to higher resistance of the wound to deformation3 and a lower risk of complications such as iris prolapse during surgery in patients at risk such as with intraoperative floppy iris syndrome (IFIS). Additional factors that have to be taken into account are the construction and the position of the incision and the influence of the extraocular force on the wound morphology.4 Another effect that may influence the wound architecture is stromal hydration at the end of surgery.5 Wound architecture has recently been assessed6-9 using optical coherence tomography. Elkady et al.10 observed the wound architecture in MICS cases focusing on corneal thickness and the incision angle. However, none of these studies observed the effect of the wound architecture on post-operative astigmatism. Furthermore, all observations in the past have been performed in the post-operative period only and information concerning the wound architecture intra-operatively is missing. A recently launched CE-marked intra-operative OCT allows observing the wound architecture intra-operatively.

One aim of the study is to assess the influence of the intra-operative wound architecture using a similar grading system as used by Calladine and Packard (2007)7 on the resistance to deformation of the wound and the surgically induced astigmatism in MICS and small incision cataract surgery (SICS). In a second part of this exploratory study the effect of a hinged incision with a pre-cut should be assessed along the same line

Condition or Disease	Intervention/Treatment	Phase
Cataract	Procedure: MICS-group Procedure: SICS-group Procedure: SICS pre-cut Procedure: SICS stab-incision	N/A

Study Design

Study Type:

Interventional

Actual Enrollment :

68 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

Triple (Participant, Investigator, Outcomes Assessor)

Primary Purpose:

Basic Science

Official Title:

Impact of Incision Size and Architecture on Wound Stability and Astigmatism in Cataract Surgery: an Exploratory Study

Study Start Date :

Feb 1, 2012

Actual Primary Completion Date :

Sep 1, 2013

Actual Study Completion Date :

Sep 1, 2013

Arms and Interventions

Arm	Intervention/Treatment
Active Comparator: MICS-group	Procedure: MICS-group Micro incision cataract surgery is done
Active Comparator: SICS-group	Procedure: SICS-group small incision cataract surgery is done
Active Comparator: SICS pre-cut	Procedure: SICS pre-cut Small incision cataract surgery with pre-cut is done
Active Comparator: SICS stab-incision	Procedure: SICS stab-incision Small incision cataract surgery with stab-incision is done

Outcome Measures

Primary Outcome Measures

o Correlation between a wound architecture score (developed during the study) and the post-operative astigmatism for the "MICS", the "SICS", the "SICS pre-cut" and the "SICS stab-incision" group [pre-operatively to one day post-operativly]

Eligibility Criteria

Criteria

Ages Eligible for Study:

21 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion Criteria:

Age-related cataract
Age 21 and older
written informed consent prior to recruitment

Exclusion Criteria:

Pregnancy (pregnancy test will be taken pre-operatively in women of reproductive age)
Any ophthalmic abnormality that could compromise the measurements