Retinal pigment epithelial tear after intravitreal injection of triamcinolone acetonide for neovascular pigment epithelial detachment: a mechanical explanation

Suprachoroidally injected pharmacological agents for the treatment of chorio-retinal diseases: a targeted approach

Delivery of pharmaceuticals to the posterior segment presents challenges that arise from the anatomy and clearance pharmacokinetics of the eye. Systemic and several local administration options [topical, periocular, intravitreal (IVT) and subretinal] are in clinical use, each with a unique benefit to risk profile shaped by factors including the administered agent, frequency of dosing, achievable pharmaceutical concentrations within posterior segment structures versus elsewhere in the eye or the body, invasiveness of the procedure and the inherent challenges with some administration methods. The use of the suprachoroidal space (SCS), which is the region between the sclera and the choroid, is being explored as a potential approach to target pharmacotherapies to the posterior segment via a minimally invasive injection procedure. Preclinical data on agents such as vascular endothelial growth factor inhibitors and triamcinolone acetonide (TA) indicate that administration via suprachoroidal injection results in more posterior distribution of the pharmacologic agent, with higher exposure to the sclera, choroid, retinal pigment epithelium cells and retina, and lesser exposure to the anterior segment, than observed with IVT administration. Based in part on these findings, clinical trials have explored the efficacy and safety of suprachoroidal administration of pharmacologic therapies in conditions affecting the posterior segment. Data on a proprietary formulation of TA administered by suprachoroidal injection show improvement in anatomic and visual outcomes in subjects with noninfectious uveitis, with the potential to mitigate the known risks of cataract and increased intraocular pressure (IOP) associated with the use of intraocular corticosteroids. Suprachoroidal administration appears to be a promising treatment modality and is also in the early stages of investigation for other possible applications, such as injection of antiglaucoma agents into the anterior SCS for long-lasting control of elevated IOP, and as a mode of delivery for gene- or cell-based therapies for retinal disorders.

Retinal pigment epithelium tears after intravitreal injection of ranibizumab for predominantly classic neovascular membranes secondary to age-related macular degeneration

PURPOSE

Retinal pigment epithelium (RPE) tear is an extremely rare complication in patients with classic neovascular membranes without RPE detachment. We evaluate their incidence and functional outcome following treatment with intravitreal ranibizumab.

METHODS

Observational study of 72 consecutive patients (74 eyes) treated at Jules Gonin University Eye Hospital, Lausanne, with intravitreal ranibizumab 0.5 mg for classic choroidal neovascularization (CNV) between March 2006 and February 2008. Best-corrected visual acuity (BCVA), fundus examination and optical coherence tomography were recorded monthly; fluorescein angiography was performed at baseline and repeated at least every 3 months.

RESULTS

RPE tears occurred in four (5.4%) eyes temporal to the fovea, after a mean of four injections (range 3-6). Mean baseline BCVA was 0.25 decimal equivalent (logMAR 0.67) and improved despite the RPE tear to 0.6 decimal equivalent (logMAR 0.22).

CONCLUSION

RPE tears following intravitreal ranibizumab injections for classic CNV can occur in about 5% of patients, even in the absence of baseline RPE detachment. Nevertheless, vision may improve provided the fovea is not involved.

Retinal pigment epithelial tears in ranibizumab-treated eyes

PURPOSE

To report the incidence of retinal pigment epithelial (RPE) tears in patients treated with ranibizumab therapy for choroidal neovascularization due to age-related macular degeneration.

DESIGN

: Interventional case series.

METHODS

One hundred sixty-four eyes from a large clinical practice were retrospectively reviewed for number of injections and the presence or absence of a fibrovascular retinal pigment epithelial detachment. Main outcome measures were occurrence of RPE tears, and timing of tears following the last injection.

RESULTS

Patients were observed for an average of 11 months. A single patient (0.61%) experienced an RPE tear and this occurred after the first injection. In eyes with a fibrovascular retinal pigment epithelial detachment the incidence was 5%. Lesions containing a fibrovascular retinal pigment epithelial detachment tended to be larger (4.5 versus 3.8 Macular Photocoagulation Study Disc Areas), but this was not statistically significant. (P = 0.63). However, these lesions required more injections on average (P = 0.05).

CONCLUSION

The incidence of RPE tears associated with ranibizumab therapy is low and may result from a predisposition rather than an effect of treatment. Even so, patients undergoing ranibizumab therapy should be counseled regarding this possible complication.