Main

Sir,

We report a case of inadvertent intraocular injection of depomedrone (methylprednisolone acetate 40 mg/ml). This is a rare complication of peribulbar steroid injection. The need for the procedure to be performed must be strongly assessed in view of the potential complication of perforation.

Case report

A 71-year-old gentleman underwent uneventful left cataract extraction and posterior chamber implant insertion in September 1999. He developed refractory cystoid macular oedema (CMO) 2 months postoperatively, unresponsive to topical/oral steroids and topical nonsteroidal anti-inflammatories. He started to develop osteoporotic joint symptoms while on oral steroids; hence the decision was made to perform a peribulbar steroid injection to reduce systemic steroid sideeffects. A sharp 25-gauge 16-mm needle was introduced transconjunctivally at the junction of the outer third and medial two-thirds of the lower orbital margin. Some resistance to insertion was experienced during needle entry. Aspiration check revealed no blood or fluid. A measure of 1 ml of depomedrone was injected. This was perceived by the patient to be uncomfortable at the time. The eye was then double padded and the patient was asked to keep the pad on till later that day.

The patient presented 24 h later, as an emergency, with reduced vision in the left eye. He reported that he was aware of floaters in the eye soon after the peribulbar injection. Visual acuity prior to the injection was 6/9, and was count fingers 24 h postinjection. Examination findings were a subconjunctival haemorrhage in the left inferior fornix; anterior chamber debris and white globules of depomedrone were noted floating in the vitreous with some coating the retina inferiorly (Figure 1). The IOP was 12 mmHg. He was commenced on oral ciprofloxacin and topical ofloxacin, atropine, and dexamethasone.

Figure 1
figure 1

Slit-lamp photograph showing depomedrone globules in the anterior chamber.

Full size image

An ultrasound B scan was performed, which revealed vitreous detachment with a mobile subhyaloid collection (Figure 2). No retinal elevation was noted.

Figure 2
figure 2

Ultrasound B scan showing subhyaloid collection of depomedrone (arrowhead).

Full size image

A pars plana vitrectomy was performed at the earliest available opportunity, which was just over 48 h after the perforation. Laser retinopexy to needle entry site and air/fluid/gas (C3F8) exchange was performed. Postoperative posturing was advised.

He underwent an uneventful postoperative recovery and his visual acuity gradually improved to 6/12 and N5 over a 2-month period. FFA performed 2 months postoperatively revealed persisting CMO. Visual acuity gradually recovered over the following 10 months to 6/9 with eventual resolution of the CMO.

Comments

Vitrectomy1 and intravitreal steroid injection (triamcinolone)2,3 have both been advocated in the management of refractory CMO. However in this case, neither the vitrectomy itself nor the intraocular steroid exposure seemed to have any beneficial effect on the CMO. In fact, the suggested safe dose for intraocular administration of the triamcinolone preparation is almost 20-fold less than that of the steroid injected in this case.4

To our knowledge, there have only been 13 cases of inadvertent intraocular depomedrone injections reported.5,6,7,8,9,10 Many were managed conservatively, which mostly lead to serious complications such as ascending optic atrophy.5,6 Vitrectomy has been regarded as the treatment of choice for the last 15 years or so. Previous reports advocate immediate vitrectomy to achieve better prognosis;10 our case was operated on over 48 h following the injection and the visual outcome was satisfactory. This suggests that the intraocular residence time of the depomedrone may not have an adverse effect on visual outcome, although longer residence times may be associated with an increased incidence of complications such as those noted in conservatively managed cases.

The incidence of perforation during peribulbar injection of local anaesthetic has been reported up to 1 in 874.11 In order to try and reduce perforation rates, alterations in technique have been suggested such as watching for corresponding globe movement whilst performing horizontal movements of the needle. This is done following needle insertion but prior to injection.12 The introduction of newer techniques of periocular steroid administration, such as blunt cannula subtenon injection, avoids the need to introduce a sharp instrument into the orbit, thereby reducing incidences of inadvertent ocular perforation.