Intrastromal Corneal Ring for High Astigmatism on Postkeratoplasty (Anel)

This study has been completed.
Sponsor:
Information provided by:
Instituto de Olhos de Goiania
ClinicalTrials.gov Identifier:
NCT01018797
First received: November 21, 2009
Last updated: November 23, 2009
Last verified: November 2009
  Purpose

To evaluate the clinical outcomes of Intrastromal Corneal Ring Segment (ICRS) implantation to correct high-degree astigmatism on eyes with prior penetrating keratoplasty (PK).


Condition Intervention Phase
Astigmatism
Procedure: INTRASTROMAL CORNEAL RING SEGMENT
Phase 4

Study Type: Interventional
Study Design: Endpoint Classification: Safety/Efficacy Study
Intervention Model: Single Group Assignment
Masking: Single Blind (Investigator)
Primary Purpose: Treatment
Official Title: Intrastromal Corneal Ring Segment Implantation for High Astigmatism on Postkeratoplasty Eyes

Further study details as provided by Instituto de Olhos de Goiania:

Enrollment: 18
Study Start Date: January 2007
Study Completion Date: November 2009
Primary Completion Date: July 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: INTRASTROMAL CORNEAL RING SEGMENT
Eighteen eyes of 18 patients, 8 men and 10 women, with high levels (> 5 diopters [D]) of postkeratoplasty astigmatism were studied in a nonrandomized, retrospective, observational case series. PK was performed to treat keratoconus in 15 patients, corneal scar after trauma in 2 patients, and Fuchs endothelial dystrophy in 1 patient.
Procedure: INTRASTROMAL CORNEAL RING SEGMENT
Corneal tunnels were created by means of mechanical dissection in all eyes. Intrastromal corneal ring segments implantation was indicated because of the existence of reduced best spectacle-corrected visual acuity (BSCVA) or contact lens intolerance.

Detailed Description:

Eighteen eyes of 18 patients, 8 men and 10 women, with high levels (> 5 diopters [D]) of postkeratoplasty astigmatism were studied in a nonrandomized, retrospective, observational case series. Mean age at the time of ICRS implantation was 38 years, range 22 to 49 years. PK was performed to treat keratoconus in 15 patients, corneal scar after trauma in 2 patients, and Fuchs endothelial dystrophy in 1 patient. All patients were spectacle and contact lens intolerant. There was no active corneal disease or problem apart from high astigmatism.

Minimum time of ICRS implantation was 2 years after PK and at least 6 months after sutures removal.

Preoperative examinations included personal medical ocular history, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refraction, keratometry, intraocular pressure (IOP) measurement by applanation tonometry, corneal astigmatism, surface regularity index, surface asymmetry index, tonometry, slit-lamp biomicroscopy, specular microscopy, and fundus examination.

Main outcome measures included UCVA, BSCVA, refraction, keratometry and computerized analysis of corneal topography.

All surgeries were performed by the same surgeon (BAN) at the Goiania Eye Institute, between July 2007 and January 2009. Corneal tunnels were created by means of mechanical dissection in all eyes. Intrastromal corneal ring segments implantation was indicated because of the existence of reduced best spectacle-corrected visual acuity (BSCVA) or contact lens intolerance. Intracorneal ring segments implantations were performed by the same surgeon following the same protocol. All eyes were implanted with the Cornealring (Visiontech Medical Optics, Belo Horizonte, MG, Brazil). Mean follow-up after ICRS implantation was 12 months (range, 09 to 22 months).

The procedure, its goals, and possible complications were explained and all patients signed an informed consent. The amount and axis of astigmatism to be corrected by ICRS was based on manifest refraction.

  Eligibility

Ages Eligible for Study:   21 Years to 50 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • > 5 diopters of postkeratoplasty astigmatism
  • Patients 21 to 50 years old
  • Conventional treatments have failed

Exclusion Criteria:

  • Diabetes
  • Autoimmune diseases
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01018797

Locations
Brazil
Instituto de Olhos de Goiânia
Goiânia, GO, Brazil, 74120-050
Sponsors and Collaborators
Instituto de Olhos de Goiania
Investigators
Study Chair: Belquiz A Nassaralla Instituto de Olhos de Goiânia
  More Information

No publications provided

Responsible Party: BelquizRodrigues do Amaral Nassaralla, Instituto de Olhos de Goiânia
ClinicalTrials.gov Identifier: NCT01018797     History of Changes
Other Study ID Numbers: BQ-1-09-ARVO
Study First Received: November 21, 2009
Last Updated: November 23, 2009
Health Authority: Brazil: National Health Surveillance Agency

Keywords provided by Instituto de Olhos de Goiania:
INTRASTROMAL CORNEAL RING
ASTIGMATISM
POSTKERATOPLASTY
EYES
To evaluate the clinical outcomes of ICRS implantation to correct high-degree astigmatism on eyes with prior penetrating keratoplasty (PK)

Additional relevant MeSH terms:
Astigmatism
Refractive Errors
Eye Diseases

ClinicalTrials.gov processed this record on July 23, 2014