The use of subretinal triamcinolone acetonide in the management of neovascular age-related macular degeneration: a pilot study

Tiny dexamethasone palmitate nanoparticles for intravitreal injection: Optimization and in vivo evaluation

Tiny nanoparticles of dexamethasone palmitate (DXP) were designed as transparent suspensions for intravitreal administration to treat age-related macular degeneration (AMD). The influence of three surfactants (PEG-40-stearate and Pluronic block copolymers F68 and F127) on nanoparticles size and stability was investigated and led to an optimal formulation based on Pluronic F127 stabilizing DXP nanoparticles. Size measurements and TEM revealed tiny nanoparticles (around 35 nm) with a low opacity, compatible with further intravitreal injection. X-Ray powder diffraction (XRPD) and transmission electronic microscopy (TEM) performed on freeze-dried samples showed that DXP nanoparticles were rather monodisperse and amorphous. The efficacy of DXP nanoparticles was assessed in vivo on pigmented rabbits with unilateral intravitreal injections. After breakdown of the blood-retinal barrier (BRB) induced by injection of rhVEGF165 with carrier protein, DXP nanoparticles induced a restoration of the BRB 1 month after their intravitreal injection. However, their efficacy was limited in time most probably by clearance of DXP nanoparticles after 2 months due to their small size.

Subretinal triamcinolone acetonide associated with improvement of cystoid macular edema in a patient with retinitis pigmentosa

PURPOSE

To report a case of traumatic displacement of intravitreal triamcinolone acetonide into the subretinal space.

METHODS

Single case report.

RESULTS

We describe a 17-year-old boy with retinitis pigmentosa and severe, persistent cystoid macular edema with foveal cysts resistant to surgical intervention who had marked clinical improvement after traumatic displacement of intravitreal triamcinolone acetonide into the subretinal space.

CONCLUSION

Subretinal delivery of triamcinolone acetonide may be more effective than preretinal steroid administration in reducing foveal cysts, particularly in retinitis pigmentosa. In this case, the duration of triamcinolone acetonide in the subretinal space seemed to be on the order of 3 months.

Natural history of sub-retinal triamcinolone acetonide deposition after triamcinolone-assisted vitrectomy

PURPOSE

To describe the natural course of subretinal triamcinolone acetonide (TA) deposition after a TA-assisted vitrectomy for retinal detachment.

METHODS

Observational case series.

RESULTS

TA deposition was observed between the neurosensory retina and retinal pigment epithelium in the macular area at the conclusion of vitreoretinal surgery in three patients with retinal detachment. On follow up, TA granules gradually decreased over the next 2 weeks and resolved completely by 3 weeks. Two months after the operation, the retina was observed to be successfully attached and no ophthalmoscopic or functional damage was observed.

CONCLUSION

As no apparent clinically detectable adverse effect was found in the three cases that demonstrated subretinal deposition of TA we opine that active surgical maneuvers to remove the same are not warranted during surgery.

Evaluation of Subretinal Triamcinolone Acetonide in Patients with Exudative Age-Related Macular Degeneration

PURPOSE

The aim of this paper was to present the results of subretinal delivery of triamcinolone acetonide (TCA) in humans with choroidal neovascularization (CNV) caused by age-related macular degeneration (AMD).

METHODS

Twenty two (22) eyes of 22 patients underwent pars plana vitrectomy with subretinal TCA administration. Two milligrams (2 mg) of preservative-free TCA were delivered through a 32-gauge automatic subretinal injector in 20 microL of volume. Visual acuity, fluorescein angiography (FA), and intraocular pressure (IOP) were recorded and compared pre- and postoperatively.

RESULTS

Preoperative average+/-standard deviation visual acuity in the treated eye was 1.408+/-0.129 (logMAR; median 20/400) and 1.403+/-0.114 (logMAR; median 20/300) postoperatively (P=0.51). The mean area of pre- and postoperative FA leakage in the operated eyes was 21.31+/-1.125 and 19.29+/-1.108 mm2, respectively (P=0.04). The average IOP value before treatment was 15.3+/-0.78 mmHg. Three (3) months after surgery, it was 20.5+/-2.04 mmHg (P=0.02). Six (6) months and 1 year after surgery, the average IOP was 17.0+/-0.66 mmHg (P=0.9) and 15.6+/-1.02 mmHg (P=0.6), respectively.

CONCLUSIONS

Subretinal TCA stabilizes visual acuity, decreases FA leakage in eyes with CNV owing to AMD, and does not increase IOP, as seen with intravitreous injections.