Late-onset Hypotony Maculopathy After Trabeculectomy in a Highly Myopic Patient With Juvenile Open-angle Glaucoma

Abstract

Hypotony maculopathy is a sight-threatening complication after trabeculectomy. We report on a 34-year-old man with juvenile open-angle glaucoma and high myopia, who developed hypotony maculopathy 14 years after trabeculectomy without bleb leak. This represents the longest known period from trabeculectomy to the development of hypotony maculopathy without bleb leak. The possible mechanisms for the development of late-onset hypotony maculopathy in the highly myopic patient are progressive scleral thinning, reduced scleral rigidity, and scleral morphologic change with aging. These changes might weaken the biomechanical properties of sclera and then contribute to the collapse of the scleral wall during hypotony. This case serves as a reminder that hypotony maculopathy can happen up to 14 years after tabeculectomy even without bleb leak and hypotony should be avoided after trabeculectomy in highly myopic patients with juvenile open-angle glaucoma.

Chorioretinal Folds in the Trabeculectomized Eye with Normal Intraocular Pressure after Phacoemulsification

“…Any cause of IOP lowering might add insult to injury in a weakened sclera. The sclera in patients with high myopia may not be sufficiently strong to maintain the contour of the posterior globe and make the globe similar to a deflated balloon [ 19 ]. Thus, tractional forces exerted by the inferior oblique muscle at its insertion point located behind the macular area can result in CRFs [ 20 ].…”

Glaukomassoziierte Makulopathien

“…Ein niedriger Augendruck allein reicht für die Entwicklung einer hypotonen Makulopathie nicht aus. Gewisse biomechanische Eigenschaften der Sklera, wie Skleradicke, Sklerarigidität und strukturelle Veränderungen im Skleragewebe, spielen eine wesentliche Rolle in der Pathogenese einer hypotonen Makulopathie 38 , 52 .…”

“…Das Skleragewebe besteht aus einem Gerüst von Kollagenfasern umgeben von Proteoglykanen, wodurch die biomechanischen Eigenschaften der Sklera bestimmt werden 52 , 53 . Mit zunehmendem Alter kommt es zu einer progredienten Degeneration der Kollagenfasern, einem Verlust der Proteoglykane und einer Dehydrierung der Sklera.…”

“…Die häufigsten Ursachen dafür sind eine Hyperfiltration oder eine Leckage des Sickerkissens. Tritt die Hypotonie > 1 Monat postoperativ auf, wird sie als „Late-Onset“-Hypotonie bezeichnet 34 , 37 , 38 , 46 , 52 . In der Arbeit von Kao et al wird das Auftreten einer HM bei einem 34-jährigen Patienten mit einem juvenilen Glaukom 14 Jahre nach Trabekulektomie (TET) beschrieben 52 .…”

Techniques of Bleb Repair

“…With the advent of use of anti metabolites like mitomycin-C and 5-fluorouracil in filtering surgery, although there is an increase in the life of the filtering bleb 1 , bleb-associated complications have also increased manifold. 2 These complications can also be seen without their use; like in congenital glaucoma 3 and high myopia 4 as the conjunctiva covering the bleb is relatively thin and friable and becomes more cystic when it comes in contact with aqueous humor. There can be early onset (within days) or late onset bleb related complications.…”