Central Versus Peripheral Air Injection for DALK (Deep Anterior Lamellar Keratoplasty)

NCT02485951 | Completed

• 1 other identifier: ShaheedBMU54
• Study Type: interventional
• Target: 49
• Locations: 1 country
• Sites: 1

Brief Summary

Different techniques of deep anterior lamellar keratoplasty (DALK) have been introduced to create a uniform recipient bed, thereby reducing complications, such as interface irregularity and opacification encountered with conventional lamellar keratoplasty. The big-bubble technique provides a planned, safe, quick and consistent baring of Descemet membrane (DM) by injection of air deep into the stroma. Nevertheless, this technique has a long learning curve with a low success rate of big-bubble formation and a high rate of DM perforation when performed by surgeons in training. Different modifications to the original technique using intraoperative instruments such as corneal pachymetry, anterior segment optical coherence tomography (OCT), and femtosecond laser, have been used to increase the chances of achieving a successful DM detachment from the deep stroma by air injection. Even with these innovations, the rate of successful big-bubble formation did not reach 100%. Recently, the investigators described a modification to the original big-bubble DALK in which a 27-gauge needle was inserted into the stroma peripherally from the trephination site towards the limbus. The investigators found that air injection peripheral to the trephination can effectively and reproducibly separate the corneal stroma from the Descemet membrane (DM). This study was aimed to compare the success rate and complications of big-bubble DALK using central versus peripheral air injection performed by senior cornea fellows under the supervision of an experienced faculty member in an academic hospital.

Conditions

Keratoconus

Keywords

deep anterior lamellar keratoplasty; big-bubble technique; peripheral air injection; keratoconus

Outcome Measures

Primary Outcomes (1)

• The rate of successful big-bubble formation

  One year

Study Arms (2)

Central air injection

ACTIVE COMPARATOR

The needle was moved radially inside the trephination site and advanced to the central or paracentral cornea.

Procedure: Central air injection

Peripheral air injection

ACTIVE COMPARATOR

The needle was inserted into the deep stroma from the trephination site and advanced into the peripheral cornea to approximately 1.5 mm anterior to the limbus.

Procedure: Peripheral air injection

Interventions

Central air injection PROCEDURE

Air was injected inside the trephination site in the central injection group.

Central air injection

Peripheral air injection PROCEDURE

Air was injected at the corneal periphery outside the trephination site.

Peripheral air injection

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Patients with moderate (48 D \< mean keratometry \< 55 D) to advanced (mean keratometry ≥ 55 D or immeasurable keratometry) keratoconus were enrolled.

You may not qualify if:

• History of ocular surgery, concomitant ocular pathologies, such as vernal keratoconjunctivitis, cataract, glaucoma, and retinal abnormalities.

Sponsors & Collaborators

• Shahid Beheshti University of Medical Sciences: lead

Study Sites (1)

Ophthalmic Research Center

Tehran, Iran

Location

MeSH Terms

Conditions

Keratoconus

Condition Hierarchy (Ancestors)

Corneal Diseases; Eye Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD

Study Record Dates

• First Submitted: June 13, 2015
• First Posted: June 30, 2015
• Study Start: January 1, 2014
• Primary Completion: June 1, 2015
• Last Updated: April 20, 2016

Record last verified: 2015-06

Locations

IR (1)