Management of Patients With Keratoconus With Intacs

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

TERMINATED

Clinical Phase

NA

Total Enrollment

25 participants

Study Classification

INTERVENTIONAL

Study Start Date

2000-01-31

Study Completion Date

2006-07-31

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

Purpose To evaluate long-term follow up of Intacs microthin prescription inserts (Addition Technology Inc, Fremont, Calif) for the management of keratoconus.

Design A long-term (five years) retrospective, follow-up study

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

Subjects and Methods

Ethical committee approval was obtained for the original trial, and patients were asked to sign an informed consent form (in accordance with Institutional guidelines and to the Declaration of Helsinki) before treatment and for further follow-up examinations. The registration information for this clinical trial is available to the public through the National Institute of Health database.

The surgical procedure was done under topical anesthesia. Two Intacs segments of 0.45-mm thickness were inserted so as to embrace the steepest keratoconus meridian, according to the topographic image, aiming at maximal flattening.

The corneal thickness was measured intraoperatively at the incision site and peripherally in the cornea along the ring placement markings with ultrasonic pachymetry (Sonogage, Cleveland, Ohio, USA). Using a diamond knife, set at 70% of the thinnest corneal measurement, a 0.9-mm radial incision was formed, and corneal pockets were created using two Sinskey hooks and a Suarez spreader. Two corneal tunnels were then formed using clockwise and counterclockwise dissectors under suction created by a vacuum-centering guide. The two polymethyl methacrylate (PMMA) segments (0.45-mm thickness) were implanted in the respective corneal tunnels, maintaining a space of approximately 2.0-mm between their ends and 1.5 mm between the opposite edge of each segment and the edge of the incision. The incision site was sutured using a single 10/0 nylon stitch.

Postoperative evaluation Postoperatively, all eyes received antibiotic/steroid combination eye drops 4 times per day for 2 weeks. In addition, all patients were instructed to use preservative-free artificial tears frequently. The sutures were removed 2 weeks after surgery.

Group differences for continuous variables were tested using the paired Student t tests. The change in manifest refraction (spherical equivalent) (MRSE) and topographic k values and topographic astigmatism were plotted over time to determine long-term stability, and the difference as a function of time was analyzed using paired 2-tailed t tests (at time intervals of preoperative to 1 month, 1 to 3 months, 3 to 6 months, 6 to 12 months, and every year of follow up period). Results are presented as means + standard deviation \[SD\]. A P value less than .05 was regarded as statistically significant.

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Keratoconus

Keywords

Explore important study keywords that can help with search, categorization, and topic discovery.

keratoconus Intacs

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

NON_RANDOMIZED

Intervention Model

SINGLE_GROUP

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

Intacs

Intervention Type DEVICE

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* All patients had clear central corneas and contact lens intolerance (rigid gas permeable contact lenses intolerance, frequent contact lens displacement, unsatisfactory visual acuity),

Exclusion Criteria

* history of herpes keratitis; diagnosed autoimmune disease; and systemic connective tissue disease.

Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

Yes

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

George D Kymionis, M.D., Ph.D

Role: PRINCIPAL_INVESTIGATOR

University of Crete

References

Explore related publications, articles, or registry entries linked to this study.

Alio JL, Shabayek MH, Artola A. Intracorneal ring segments for keratoconus correction: long-term follow-up. J Cataract Refract Surg. 2006 Jun;32(6):978-85. doi: 10.1016/j.jcrs.2006.02.044.

Reference Type RESULT

PMID: 16814056 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

PEPAGNI-6175

Identifier Type: -

Identifier Source: org_study_id