Intraocular Pressure Changes following Intravitreal Topotecan 90 μg/0.18 cc for the Treatment of Retinoblastoma

The aim of this study was to investigate the impact of injecting Topotecan 90 μg/0.18 cc on intraocular pressure (IOP) in children with retinoblastoma.

This was a retrospective study of 78 eye encounters of 37 patients with retinoblastoma (22 males, 15 females, mean age: 3.5 ± 2.2 years, range 0.50-7.96 years) injected with intravitreal 90 μg topotecan with 0.18 mL volume. IOP was measured with a Schiotz tonometer at baseline prior to injecting, after digital massage, and then at specified time intervals following intravitreal injection of topotecan 90 μg in 0.18 mL volume. Mean arterial pressure (MAP) was either calculated from anesthesia records or recorded during anesthesia.

Mean preinjection IOP was 7.6 ± 2.5 mm Hg (range: 2-20 mm Hg). Mean IOP 60 s after intravitreal topotecan was 37.3 ± 17.4 mm Hg (range: 20-82 mm Hg). The IOP of 93.6% of patients was less than the MAP at all observed time points after injection. In patient eye encounters where IOP exceeded MAP, IOP resolved to below MAP in 4 min in all encounters. Additionally, in 4 min, 91% of patient eye encounters had IOP of below 29 mm Hg.

Topotecan 90 μg/0.18 cc dose is increasingly important for retinoblastoma treatment. Injection of intravitreal topotecan 90 μg/0.18 cc chemotherapy caused a transient rise in IOP with spontaneous resolution below MAP for all patients after 4 min without further intervention. This is the first study of intravitreal topotecan 90 μg/0.18 cc on IOP and provides reassurance for the safe use of higher dose and volume of topotecan 90 μg/0.18 cc.