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Sir,

Peribulbar anaesthesia using lignocaine or bupivicaine is frequently used in ophthalmic surgery. Hyaluronidase is often used as an adjunct to aid dispersal of these agents.1,2,3,4 We report a case of orbital inflammation secondary to delayed postoperative hyaluronidase allergy leading to visual loss.

Case report

A 77-year-old lady with advanced primary open angle glaucoma treated by bilateral trabeculectomies developed a cataract in her left eye, reducing her best-corrected visual acuity to 6/24 part. Previous uneventful right phacoemulsification under local anaesthesia had improved vision to 6/9 despite advanced bilateral glaucomatous field loss (not shown). She was also known to suffer from osteoarthritis, angina, atrial fibrillation, hypertension, but no known allergies.

She underwent uneventful sutureless left phacoemulsification and lens implant under local anaesthesia. At 24-hours postoperatively her left eye was comfortable and quiet, with unaided vision of 6/18. After 28-h later she presented with periorbital swelling of the left eye associated with nausea and vomiting of 4 h duration.

Her visual acuity was 6/12 in the right eye and hand movements in the left eye. Her left eyelids were tender and very oedematous being unable to spontaneously open her eye (Figure 1). Intraocular pressures (IOP) were 12 and 20 mmHg, respectively. The pupils were equal and reactive with no evidence of a relative afferent pupil defect. Left ocular motility was restricted in all directions of gaze with 3 mm of axial proptosis. Slit lamp biomicroscopy revealed a clear cornea and quiet anterior chamber. The left optic disc was pale, fully cupped with a splinter haemorrhage.

Figure 1
figure 1

Hyperaemic and swollen left eyelids with inability to spontaneously open the left eye.

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CT scan confirmed left-sided proptosis with preseptal oedema, increased intraconal soft tissue density, and minimal extra-ocular muscle enlargement. The paranasal sinuses were clear (Figure 2). A full blood count, erythrocyte sedimentation rate, electrolytes, and blood glucose were normal. Blood cultures were negative, but a conjunctival swab grew coagulase negative Staphylococcus (sensitive to coamoxyclav).

Figure 2
figure 2

CT scan of both orbits. Left (axial): left proptosis with preseptal oedema, increased intraconal soft tissue density, minimal extraocular muscle and lacrimal gland enlargement. Right (coronal): Minimal extraocular muscle enlargement and clear paranasal sinuses.

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At this stage, our differential diagnosis included orbital cellulitis, allergic orbital inflammation, and retrobulbar haemorrhage.

The episode was initially managed as orbital cellulitis, since there was no evidence of allergy 24 h after surgery and the use of systemic steroids could predispose to cavernous sinus thrombosis.

Eight-hourly intravenous coamoxyclav 1.2 g and metronidazole 500 mg were commenced. Chlorpheniramine 10 mg was also administered intravenously twice daily along with intravenous fluids and analgesia.

After 24-h later, systemic improvement was apparent, although the ocular features remained unchanged. The following day, she was noted to have developed a left relative afferent pupil defect. The intraocular pressure of the left eye was 21 mmHg, for which 0.5% apraclonidine was given.

Over the next 2 days, the ocular and systemic signs improved and the intravenous antibiotics were switched to oral. At 1 week, the proptosis had regressed and she was able to open her left eye. Ocular motility was full, but her left visual acuity remained at hand movements. She was discharged on topical prednisolone 1%, timolol 0.25% and brimonidine 0.2% to the left eye.

After 2 weeks later her left visual acuity remained hand movements, with an IOP of 17 mmHg and a fully cupped optic disc. She was referred for allergy testing.

She was skin-prick tested for lignocaine, bupivicaine, hyaluronidase, adrenaline, mepivicaine, prilocaine, rubber, latex, and house dust mites. Skin-prick testing was strongly positive for hyaluronidase but negative for all other allergens.

Comment

Adverse reactions to periocular injections may arise either from the anaesthetic compound itself or from the mechanical manipulation of the needle.1

Three previous case reports of hyaluronidase allergy were available on literature review. The onset of allergic response reported was found to be variable, ie immediate (intraoperative), early (within a few hours), intermediate (within a few days), and late (within weeks). The present case had an intermediate onset.

All but one of the cases reported to date had a previous uneventful retrobulbar anaesthetic containing hyaluronidase. Primary sensitisation seemed a prerequisite to such an allergic response. The variability in onset of symptoms following exposure to the offending allergen and response to skin testing would suggest that type I and type IV hypersensitivity might both contribute to this response.

Kempeneers et al1 reported a series of five patients with hyaluronidase-induced orbital pseudotumour as a complication of retrobulbar anaesthesia. Four of the five patients were sensitive to hyaluronidase on intradermal testing of all anaesthetic components. Four of the five patients were exposed to retrobulbar anaesthesia for the second time while one was subjected to it for the first time. The onset of symptoms of orbital inflammation ranged from a few hours to a few weeks. Lymphocytic transformation tests (LTT) revealed a delayed hypersensitivity reaction.

Minning et al5 reported a case of intraoperative hyaluronidase allergy simulating an expulsive choroidal haemorrhage. This patient had a previous uneventful retrobulbar injection containing hyaluronidase. Skin testing confirmed an allergy to hyaluronidase. Taylor et al6 also reported a similar case of intraoperative hyaluronidase allergy during intracapsular cataract extraction. Allergic angioedema following local anaesthesia for dental and ophthalmic surgery has been described, the causative allergen being hyaluronidase.7

This case is the first case report of hyaluronidase allergy with peribulbar anaesthesia for sutureless phacoemulsification and intraocular lens implant rather than extracapsular cataract surgery.

This case demonstrates that despite being less common than infection, allergy can account for delayed postoperative orbital inflammation following intraocular surgery. Detection of an allergy to hyaluronidase suggests that systemic steroids may have been of benefit once an infective focus had been ruled out. Secondly, there is a case for avoiding the use of hyaluronidase in patients who have had previous periocular local anaesthesia, particularly if the optic nerve is vulnerable, as in patients with advanced glaucoma.

Proprietary interests: None.