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Comparison of Penetrating Keratoplasty and Deep Lamellar Keratoplasty With the Big Bubble Technique for Keratoconus

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified January 2007 by Shahid Beheshti University of Medical Sciences.
Recruitment status was:  Active, not recruiting
Information provided by:
Shahid Beheshti University of Medical Sciences Identifier:
First received: August 31, 2006
Last updated: January 12, 2007
Last verified: January 2007
it is a randomized clinical trial to compare deep lamellar keratoplasty (DLK) Using big bubble technique and Penetrating Keratoplasty (PK) in patients with keratoconus

Condition Intervention Phase
Keratoconus Procedure: keratoplasty Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single
Primary Purpose: Treatment

Resource links provided by NLM:

Further study details as provided by Shahid Beheshti University of Medical Sciences:

Primary Outcome Measures:
  • Uncorrected visual acuity (UCVA), best corrected visual acuity(bcva), refractive astigmatism, endothelial cell density, mean cell area, polymegathism (CV), Contrast sensitivity, Root-mean-square (RMS) Wavefront error, Pearson correlation factor between

Estimated Enrollment: 50
Study Start Date: July 2006
Estimated Study Completion Date: August 2006
Detailed Description:
In this randomized clinical trial 50 keratoconic eyes of 50 patients randomly assigned in two groups: 25 patients underwent DLK with the big bubble technique and the other 25 patients underwent PK with the standard technique using hessburg – Barron trephine. One surgeon performed all operations using a 16 bites separate 10-0 nylon sutures. We used A-scan ultrasonic biometry for measuring vitreous length (VL) before surgery. If VL≥15.50mm, a trephine 0.25mm larger than recipient and if VL was <15.50mm, a trephine 0.50 mm larger than recipient were considered. Selective suture removal was started 3 months after operation. quality of vision endothelial cell changes and correlation between refractive outcome and VL in relation to donor-recipient disparity, were measured and analyzed in both PK and DLK 15 mos postoperatively.

Ages Eligible for Study:   15 Years to 50 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • moderate to severe keratoconus
  • contact lens intolerance
  • low visual acuity due to anterior stromal scar
  • age between 15 to 50 years

Exclusion Criteria:

  • posterior stromal scar with descemets membrane involvement
  • history of hydrops
  • fuchs endothelial dystrophy
  • glaucoma
  • cataract
  • history of intraocular surgery
  • history of vernal keratoconjunctivitis
  • intraoperative complications
  • reoperation (resuturing- regraft)
  Contacts and Locations
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Please refer to this study by its identifier: NCT00371202

Iran, Islamic Republic of
Bahram Einollhi, MD
Tehran, Iran, Islamic Republic of, 16666
Sponsors and Collaborators
Shahid Beheshti University of Medical Sciences
Principal Investigator: Bahram Einollahi, MD Ophthalmic Research Center of Shaheed Beheshti Medical University
  More Information Identifier: NCT00371202     History of Changes
Other Study ID Numbers: 8390
Study First Received: August 31, 2006
Last Updated: January 12, 2007

Keywords provided by Shahid Beheshti University of Medical Sciences:
keratoconus, penetrating keratoplasty,
deep lamellar keratoplasty
big bubble technique

Additional relevant MeSH terms:
Corneal Diseases
Eye Diseases processed this record on September 19, 2017