Autologous Partial-thickness Scleral Flap and Donor Corneal Graft in Management of Tube Erosion of Glaucoma Drainage Device

Scleral bridging technique for preventing PreserFlo microshunt exposure: A case report

INTRODUCTION

The use of the PreserFlo microshunt is gaining popularity owing to its ease of implantation and reduced need for postoperative intervention compared to conventional trabeculectomy.

PATIENT CONCERNS

However, microshunt exposure remains a severe complication of PreserFlo surgery, particularly in patients with a thin Tenon capsule and conjunctiva. However, the actual thickness and intensity of the Tenon capsule or conjunctiva can be confirmed only during surgery.

DIAGNOSIS

Exfoliation glaucoma with previous several glaucoma surgeries with thinner Tenon capsule or conjunctiva.

INTERVENTIONS

We performed PreserFlo implantation with a surgical technique to recover a thin Tenon capsule and conjunctiva by creating a half-thickness rectangular scleral flap under the shunt and covering it over the microshunt until the distal part, similar to the bridge.

OUTCOMES

The patient had better intraocular pressure control with positive cosmetic appearance using this technique.

CONCLUSION

This technique will be beneficial for both preventing exposure and holding down the top, in addition to improving cosmetic appearance.

Scleral Grafts in Ophthalmic Surgery. A Review

AIM

To summarize the history and current trends in the use of scleral grafts in ophthalmology.

MATERIALS AND METHODS

We conducted a review of the literature through the MEDLINE and Cochrane Library databases. The search terms were "sclera", "graft", and "surgery". The search resulted in 1596 articles, of which we evaluated 192 as relevant. The relevant articles were sorted chronologically and according to the method of using scleral grafts, which enabled the development of a review article.

RESULTS

The sclera has been routinely used in ophthalmology since the 1950s in many different indications. Some of these indications have become practically obsolete over time (for example, use in the surgical management of retinal detachment), but a large number still find application today (especially use in glaucoma or oculoplastic surgery, or as a patch for a defect in the sclera or cornea).

CONCLUSION

Even though allogeneic sclera is currently used less frequently in ophthalmology compared to other tissue banking products and the range of its indications has partially narrowed, it remains a useful material due to its availability and properties.

Glycerin-preserved Human-donor Corneoscleral Patch Grafts for Glaucoma Drainage Devices

PRECIS

Glycerin-preserved, human-donor, corneoscleral patch grafts are effective and safe for glaucoma drainage device (GDD) implantation, and they are comparable to previously reported materials. It can be preserved with the sterile technique for up to 12 months.

PURPOSE

To evaluate the efficacy and safety of glycerin-preserved human donor corneoscleral tissue as the patch graft for GDD implantation.

PATIENTS AND METHODS

This was a retrospective noncomparative study from the medical records of 102 eyes from 102 glaucoma patients who underwent GDD implantation by or under supervision of a single surgeon (N.K.) at the Department of Ophthalmology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand between January 2006 and December 2016. The glycerin-preserved human-donor corneoscleral tissue was used as the patch graft to cover the tube portion of GDD over the sclera. The primary outcome measure was the occurrence of patch graft-related complications.

RESULTS

There were 64 males and 38 females with the mean age of 52.8±18.5 years. The underlying diseases included failed filtration surgery with primary open-angle glaucoma 32 eyes and primary angle-closure glaucoma 15 eyes, congenital glaucoma 3 eyes and secondary glaucoma 52 eyes. The mean of ocular surgeries before GDD implantation was 2.3±1.1. Patch graft-related complications included tube exposure in 4 eyes (3.9%) and wound leakage in 4 eyes (3.9%). Eyes with tube exposure underwent regrafting 3 eyes and tube reposition 1 eye. Eyes with wound leaking resolved spontaneously 2 eyes and underwent conjunctival resuturing 2 eyes. The 5-year survival rate of the corneoscleral graft was 95.7%. There was no recurrence of graft-related complications after surgical procedure to correct the complications. Postoperatively, the mean of intraocular pressure and antiglaucoma medications decreased significantly from 27.4±9.8 mm Hg and 3.8±0.93 to 13.8±6.4 mm Hg (P<0.001) and 1.6±1.5 (P<0.001) at the last visit, respectively. The mean follow-up time was 59.9 months (range, 1 to 144.7 mo).

CONCLUSION

The glycerin-preserved human-donor corneoscleral tissue using as the patch graft was a safe alternative for GDD tube coverage. The patch graft-related complications was comparable to other materials.