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Intrastromal Corneal Ring for High Astigmatism on Postkeratoplasty

Intrastromal Corneal Ring Segment Implantation for High Astigmatism on Postkeratoplasty Eyes

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01018797
Acronym
Anel
Enrollment
18
Registered
2009-11-25
Start date
2007-01-31
Completion date
2009-11-30
Last updated
2009-11-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Astigmatism

Keywords

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)

Brief summary

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

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.

Interventions

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.

Sponsors

Instituto de Olhos de Goiania
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
SINGLE (Investigator)

Eligibility

Sex/Gender
ALL
Age
21 Years to 50 Years
Healthy volunteers
No

Inclusion criteria

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

Exclusion criteria

* Diabetes * Autoimmune diseases

Countries

Brazil

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026