Resolution of foveal pseudocyst after intravitreal triamcinolone acetonide

Abstract

Editor, Foveal pseudocyst is a specific entity occurring either as a primary ocular involvement or in the fellow eye of an eye with macular hole. Foveal pseudocyst formation may be the result of the incomplete separation of the vitreous cortex at the foveal centre and the particular structure of the foveal Müller cells (Haouchine et al. 2001). It is well known that foveal pseudocyst formation may be the first step in the development of full thickness macular hole. In the present case, optical coherence tomography (OCT) images documented the resolution of a foveal pseudocyst after an intravitreal triamcinolone acetonide injection. A 55-year-old woman presented with metamorphopsia in her right eye of 2 weeks' duration. She was in good general health and denied suffering from hypertension, diabetes, dyslipidaemia or systemic vascular diseases. Her best corrected visual acuity (VA) was 20/20 in the left eye, and 20/100 in the right eye with 1.5 dioptres of hypermetropia. Funduscopy of the right eye showed a stage 1-B impending hole with a typical yellow ring lesion (Fig. 1A). The posterior hyaloid was attached. No abnormalities were found in the left eye. Intraocular pressure and the results of anterior segment examination were normal. Examinations by OCT were performed using the OCT 3000 scanner (Carl Zeiss Ophthalmic System Inc., Humphrey Division, Dublin, California, USA) and showed a large foveal pseudocyst that occupied the entire foveal thickness, thus raising the foveal floor and disrupting the outer retinal layers (Fig. 1B). (A) Colour fundus photograph showing the yellow ring characteristic of a stage 1-B impending hole. (B) OCT showed a large foveal pseudocyst that occupied the entire foveal thickness, thus raising the foveal floor and disrupting the outer retinal layers. The patient was offered an intravitreal injection of triamcinolone acetonide (Kenacort-A, 40 mg/ml; Bristol-Myers Squibb Co, Princeton, New Jersey, USA). Topical 0.5% proparacain hydrochloride (Alcaine Alcon, Couvreur, France) was used for anaesthesia. An injection of 4 mg (0.1 ml) triamcinolone acetonide was performed through the inferior pars plana, 4 mm from the corneal limbus. The patient was fully informed about the experimental character of the treatment and had signed an informed consent form. By the end of the first month after intravitreal triamcinolone acetonide had been injected, her VA was 20/32, the foveal pseudocyst had resolved and the macular profile had returned to normal (Fig. 2). Funduscopy of the right eye showed a completely detached posterior hyaloid. The ocular examination remained stable throughout the 6-month follow-up period, during which no injection-related complications and no intraocular pressure elevation were encountered. Colour fundus photograph (A) and OCT (B) 1 month after intravitreal triamcinolone acetonide injection. Note that OCT showed a normal foveolar depression with a normal photoreceptor layer in the fovea. Foveal pseudocysts are the first step in full thickness macular hole formation, but they may evolve into a lamellar hole, may persist unchanged for months or may resolve completely. The unroofing of a foveal pseudocyst results in a lamellar hole if the base of the pseudocyst is preserved and in a full thickness hole if the outer retinal layer is disrupted. In approximately one third of cases, the pseudocyst may persist unchanged for months. The changes that occur may be the result of the incomplete separation of the vitreous cortex at the foveal centre and the particular anatomy of the foveal Müller cells (Haouchine et al. 2001). In our case, OCT images documented the resolution of a foveal pseudocyst after an intravitreal triamcinolone acetonide injection. It may be possible that the control of the glial proliferation by corticosteroid may have an effect on the healing procedure of a macular hole (Halkiadakis et al. 2003). It may also be possible that intravitreal injection of the particulates alone may have altered the vitreous gel state in such a way as to precipitate normalization of the foveal anatomy. Although spontaneous resolution of foveal pseudocyst at that stage is possible, the rapidity of resolution of the foveal pseudocyst after treatment would strengthen the cause and effect relationship of the resolution with the procedure.