Endothelial Cell Loss and Induced Astigmatism After Wound-directed and Wound-assisted IOL Injection

Cataracts Clinical Trial

Official title:

Endothelial Cell Loss and Surgically Induced Astigmatism After 2.2 mm Wound Assisted vs 2.4 mm Wound-Directed Clear Corneal Incisions for Intraocular Lens Insertion During Cataract Surgery

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01250964
• Other study ID #: 10-0435
• Status: Completed
• Phase: N/A
• First received: November 29, 2010
• Last updated: November 30, 2010
• Start date: April 2010
• Est. completion date: November 2010

Study information

• Verified date: November 2010
• Source: University of North Carolina, Chapel Hill
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to determine if there is any difference in astigmatism (eye surface curvature) or corneal endothelial cell density (the inner cell lining of the eye surface) after two different methods for inserting a lens during cataract surgery.

Description:

Cataract surgery (removal of a cloudy lens) is currently performed through increasingly smaller incisions. Bimanual surgery, where two instruments are used to remove the lens, is performed through two 1.4 mm incisions. Typically, one of these incisions is enlarged to 2.2 or 2.4 mm in order that the IOL (artificial lens) can be inserted into the eye. Surgeons insert these lenses by placing a lens injector cartridge completely into the eye (wound-directed insertion) or by placing only the tip inside the incision (wound-assisted insertion). While wound-assisted insertion can be performed through slightly smaller incisions (2.2 mm versus 2.4 mm for wound-directed insertion), both methods of insertion cause some incision enlargement. There is some evidence that wound-assisted insertion can cause very short-term pressure within the eye to go up. Neither method is considered inferior or superior to the other, and the primary investigator (Dr. Kenneth Cohen) routinely uses both methods.

No studies have directly compared wound-healing characteristics between these two methods. We seek to compare differences in:

1. Surgically-induced astigmatism (changes in the corneal curvature from cataract surgery incisions.

2. Endothelial cell density loss. Endothelial cells line the inside surface of the cornea, and their overall density can be decreased by cataract surgery.

3. Best-corrected vision after surgery

4. Sizes of the incisions after lens injection

Recruitment information / eligibility

• Status: Completed
• Enrollment: 72
• Est. completion date: November 2010
• Est. primary completion date: November 2010
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Eligible patients include those who undergo uncomplicated cataract extraction surgery and IOL implantation by KLC.

Exclusion Criteria: Patients who:

1. suffer from diabetes and have more than mild background diabetic retinopathy,

2. have a history of intraocular surgery,

3. have a history of ocular trauma,

4. have known pathology of the cornea,

5. have a history of intraocular inflammation,

6. are unable to understand English,

7. are decisionally impaired,

8. are currently incarcerated, or

9. are less than 18 years of age.

No exclusions will be made on the basis of gender, ethnicity, or race.

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Astigmatism
• Cataract
• Cataract Surgery
• Cataracts

Intervention

Procedure:
• Lens insertion during cataract surgery
After cataract removal during cataract surgery, a lens needs to be injected into the eye. Both arms are routinely used but different methods for injecting the lens.

Locations

Country	Name	City	State
United States	Kittner Eye Center	Chapel Hill	North Carolina

Sponsors (1)

Lead Sponsor	Collaborator
University of North Carolina, Chapel Hill

Country where clinical trial is conducted

United States, 

References & Publications (6)

Kamae KK, Werner L, Chang W, Johnson JT, Mamalis N. Intraocular pressure changes during injection of microincision and conventional intraocular lenses through incisions smaller than 3.0 mm. J Cataract Refract Surg. 2009 Aug;35(8):1430-6. doi: 10.1016/j.jcrs.2009.03.038. — View Citation

Kohnen T, Klaproth OK. Incision sizes before and after implantation of SN60WF intraocular lenses using the Monarch injector system with C and D cartridges. J Cataract Refract Surg. 2008 Oct;34(10):1748-53. doi: 10.1016/j.jcrs.2008.06.031. — View Citation

Masket S, Wang L, Belani S. Induced astigmatism with 2.2- and 3.0-mm coaxial phacoemulsification incisions. J Refract Surg. 2009 Jan;25(1):21-4. — View Citation

Osher RH. Microcoaxial phacoemulsification Part 2: clinical study. J Cataract Refract Surg. 2007 Mar;33(3):408-12. — View Citation

Tsuneoka H, Hayama A, Takahama M. Ultrasmall-incision bimanual phacoemulsification and AcrySof SA30AL implantation through a 2.2 mm incision. J Cataract Refract Surg. 2003 Jun;29(6):1070-6. — View Citation

Ventura AC, Wälti R, Böhnke M. Corneal thickness and endothelial density before and after cataract surgery. Br J Ophthalmol. 2001 Jan;85(1):18-20. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Surgically induced astigmatism	measured by topography at 1 month post operative visit	1 month	No
Secondary	Endothelial cell loss	As measured by specular microscopy	one month	No
Secondary	Best corrected visual acuity	By manifest refraction	one month	No
Secondary	Final incision size	measured with incision gauges before and after lens injection.	intraoperatively (day #0)	No