Clinical trial NCT00344201: Assessment of Fibrin Glue in Pterygium Surgery and Other Forms of External Eye Surgery
Official title: Assessment of Fibrin Glue in Pterygium Surgery and Other Forms of Ocular Surface Reconstruction
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE1
Conditions: Pterygium
Ocular Surface Cicatrizing Diseases
Keywords: Pterygium
Fibrin adhesive
Conjunctival graft
Ocular surface reconstruction
Lead sponsor: Singapore National Eye Centre
Sponsor class: OTHER_GOV
Collaborators: name: National University of Singapore
First posted: 2006-06-26
Enrollment: 32
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: Tisseel fibrin adhesive has been used extensively in many forms of surgery. Its use in eye surgery has been relatively recent. A few studies recently showed it was effective in securing conjunctival grafts in pterygium surgery, and in securing wounds after glaucoma and squint surgery.

We sought to confirm its effectiveness in pterygium surgery, as well as prove its effectiveness in securing other material to the ocular surface such as amniotic membrane. Our hypothesis is that fibrin adhesive is effective in securing various types of material to the ocular surface for a sufficient length of time to allow adequate healing before it is absorbed and degraded.

Detailed description: AIMS OF STUDY:

This project seeks to evaluate the efficacy of fibrin glue (Tisseel) as an alternative to conventional sutures in ocular surface reconstruction, including pterygium excision with conjunctival autografting and other forms of conjunctival and amniotic membrane surgery.

It aims to evaluate the safety and efficacy of fibrin glue in pterygium and other forms of ocular surface conjunctival and amniotic membrane surgery, as an alternative to conventional suturing. We will perform conjunctival autografting in 30 patients with primary or recurrent pterygium, and in addition, up to 20 patients undergoing either conjunctival or amniotic membrane ocular surface reconstruction for a variety of diverse ocular surface disorders including persistent epithelial defects, Stevens Johnson syndrome, chemical and thermal burns and other fornix shortening/symblepharon conditions. Efficacy endpoints will be the ability of fibrin glue to form stable adherence of the conjunctival/AM graft postoperatively, and in cases of pterygium, the percentage of pterygium recurrence at 6 months following surgery, and subjective indications of postoperative comfort/discomfort. Safety data will include the close monitoring of any potential side-effects including graft loss, infection, pain/discomfort, excessive ocular surface inflammation, epithelial breakdown, and any complications resulting in visual loss. Patients will not be charged for the fibrin glue.

If successful, the use of fibrin glue will be a useful adjunct in ocular surface reconstruction, reducing time of surgery and suture-related complications and discomfort. The cost-benefit ratio will need to be examined, but full-paying patients who can afford it may be offered fibrin glue in pterygium surgery as a surgical option.

Study Plan

This will be a non-randomized prospective series of surgical cases of pterygium surgery or ocular surface reconstruction in which the viability and efficacy of fibrin glue in replacing or augmenting sutures will be evaluated.

Patient Numbers and Selection

1. Pterygium cases: Patients will be referred by SNEC doctors to the Corneal Clinic for study counseling and enrolment. Up to 30 cases of either primary or recurrent pterygium requiring pterygium excision with conjunctival autografting will be counseled for study inclusion. The potential benefits and risks of using fibrin glue as opposed to conventional sutures will be explained with full informed consent. All surgery will be performed by the PI.
2. Other ocular surface reconstructions: Up to 20 cases of ocular surface reconstruction from the SNEC Corneal Clinic requiring suturing of conjunctival grafts or AM will be counseled for study inclusion. Significant variations in diagnosis and indications exist for ocular surface transplantation and are too numerous to elucidate, but cases will generally include ocular surface and fornix reconstructions following symblepharon and cicatrizing disorders, chemical and thermal burns, etc. The potential benefits and risks of using fibrin glue as opposed to conventional sutures will be explained with full informed consent. All surgery will be performed by the PI.

All patients will be followed up at 1 day post-operatively, 1 week, 1 month, 3 months and 6 months. Regular slit-lamp anterior segment photography and detailed recording of the status of the grafts will be performed.

Procedures and Data Collection

The patients will be fully informed of the aim and procedures of the study.

The following data will be captured:

1. Visual acuity on standard Snellen chart
2. Pterygium Grading (T1-3)
3. Documentation of pterygium location, primary or recurrent status
4. Slit-lamp photography, pre- and post-surgery
5. subjective assessment of postoperative discomfort
6. Practical benefits anticipated from successfully completed project (1/2 page)

If successful, the use of fibrin glue will be a useful adjunct in ocular surface reconstruction, significantly reducing surgical time, and obviating suture-related complications and discomfort. The cost-benefit ratio will need to be examined, but full-paying patients who can afford it may be offered fibrin glue in pterygium surgery as a surgical option. Up to 3 consecutive cases can be performed with one Tisseel unit.

Eligibility criteria: Inclusion Criteria:

1. significant pterygium clinically requiring excision
2. willingness to participate in research project and to attend research clinic

Exclusion Criteria:

1. age \< 18 years
2. other concurrent corneal pathology
3. poor acuity due to other ocular pathology
4. poor general health

Primary outcomes:
measure: Graft dislocation
timeFrame: 3 months
measure: Pterygium recurrence
timeFrame: 6 months
Secondary outcomes:
measure: Graft dimensions
timeFrame: 6 months
measure: Patient comfort on visual analogue scale
timeFrame: 1 month
measure: Visual acuity
timeFrame: 6 months
Other outcomes:
Locations:
city: Singapore
country: Singapore
facility: Singapore National Eye Centre
Study officials:
affiliation: Singapore Eye Research Institute
name: Donald TH Tan, FRCOphth
role: PRINCIPAL_INVESTIGATOR
affiliation: Singapore National Eye Centre
name: Yong M Por, FRCS
role: PRINCIPAL_INVESTIGATOR
References:
citation: Tan DT, Chee SP, Dear KB, Lim AS. Effect of pterygium morphology on pterygium recurrence in a controlled trial comparing conjunctival autografting with bare sclera excision. Arch Ophthalmol. 1997 Oct;115(10):1235-40. doi: 10.1001/archopht.1997.01100160405001.
citation: Koranyi G, Seregard S, Kopp ED. Cut and paste: a no suture, small incision approach to pterygium surgery. Br J Ophthalmol. 2004 Jul;88(7):911-4. doi: 10.1136/bjo.2003.032854.
citation: Cohen RA, McDonald MB. Fixation of conjunctival autografts with an organic tissue adhesive. Arch Ophthalmol. 1993 Sep;111(9):1167-8. doi: 10.1001/archopht.1993.01090090017006. No abstract available.
citation: Biedner B, Rosenthal G. Conjunctival closure in strabismus surgery: Vicryl versus fibrin glue. Ophthalmic Surg Lasers. 1996 Nov;27(11):967.
citation: Schlag G , Redl H. Fibrin Sealant in Operative Medicine. Vol 2.Ophthalmology, neurosurgery. Berlin, Heidelberg: Springer Verlag, 1986.