Identification of foreign bodies on the ocular surface after uneventful intravitreal injections

Abstract

Editor, Intravitreal injections with anti-Vvascular endothelial growth factor (VEGF) for various retinal diseases have become very common intraocular procedures worldwide. Known but rare complications to intravitreal injections are endophthalmitis, uveitis, an increase in intraocular pressure, retinal detachment and retinal tear (Day et al. 2011; Meyer et al. 2011). In addition, approximately 10% of the patients experience a self-limiting postinjection discomfort (Rodrigues et al. 2011). Although this surface discomfort is not sight threatening, it may affect the willingness of the patients to continue the treatment, in particular because of its repetitive nature. Here, we describe a potential cause of discomfort owing to foreign bodies after intravitreal injections of 0.05 ml ranibizumab (Lucentis; Genentech, South San Francisco, CA, USA), because we found small plastic particles on the ocular surface of patients during four procedures. All procedures were performed on different patients, at different dates and by different surgeons. To our knowledge, this has not been reported earlier. All patients had previously received uncomplicated intravitreal injections and they had all been done in the same manner. Injections are at our department routinely given under sterile conditions in an operating room with the patient in supine position without the use of a surgical microscope. Disinfection of the eyelids was carried out with topical 5% povidone-iodine and topical anaesthesia (0.5% tetracaine and 0.4% oxybuprocain). Handling and preparation of the 0.05 ml ranibizumab was performed under sterile conditions and according to the manufactures instructions. The medication was used before the expiration date. We used the package supplied 1-ml syringe, 18-gauge filter-needle [BD – BD Blunt Fill Needle - Filter 18G 1½ 1.2 × 40 mm (5 mikr.m.) REF305211] and the 30-gauge injection needle (BD Microlance 30G 0.3 × 13 mm REF 304000). 0.05 ml of ranibizumab was sucked up from the capped vial into the filter-needle (18G). The filter-needle was then exchanged with the injection needle (30G), which was attached on to the syringe. A sterile 40 × 40 centimetre surgical drape with a prefabricated ocular opening was placed over the eye, and an eye speculum was used to fixate the lashes. During the intravitreal injections, small plastic foreign bodies on the ocular surface were immediately observed after the intravitreal injection was completed, but before the eye speculum was removed. The foreign bodies were flat, transparent, purple in colour and with varying shape and a maximum size of 1 × 0.5 mm (Fig. 1A). The foreign bodies were removed from the limbus area and inferior fornix using a cotton tip (Fig. 1A). After removal of the particles, the procedure was completed with removal of the eye speculum and surgical drape, without further complications. No postinjection discomfort was reported. Cotton tip with the plastic particles (arrows) removed from the ocular surface (A). Superficial defect (arrow) in the plastic of 18-gauge filter-needle (B). The plastic foreign bodies, probably originated from the surface of plastic part of the filter-needle, were small, and superficial defects were found (Fig. 1B). These defects might have been caused by the manual attachment and removal of syringe from the filter-needle during preparation of the 0.05 ml ranibizumab. The particles may have been transferred to the ocular surface by sticking to the sterile surgical gloves. This is not the first time that plastic particles have been reported to shed from syringes (Cant et al. 1988) and silicone oil microdroplets originating from syringes have been reported intraocularly after anti-VEGF treatment (Kocabora et al. 2010). If the particles had not been removed they had most likely caused foreign body sensation and might have lead to infection or corneal epithelial damage. We suggest that care should be taken to observe for potential foreign bodies even though the intravitreal injection is given under sterile condition, and patients with continuous ocular discomfort after intravitreal injections should be evaluated for possible foreign bodies.