A rapidly enlarging swelling of the left orbit

A previously well 16 year old girl presented to acute medical admissions (walk-in assessment clinic) with a one week history of swelling of her left eyelid. She was prescribed amoxicillin for a presumed folliculitis.

She re-presented one week later to the emergency department because the swelling had steadily worsened over the past two weeks. It was tender to palpation but there was no pain with movement. Visual acuity was reduced in the left eye to 6/9 (previously 6/6), and although the swelling appeared to push her left eye “down and to the side” she denied diplopia. Pupils were equal and reactive, and the conjunctiva on the left was mildly injected superonasally. Her eye movements were normal. She had no history of trauma, insect bites, fever, or fatigue. Blood test results were unremarkable.

Her medical history consisted of two right eyebrow cysts removed six years earlier. Family history included a mother with three basal cell carcinomas and a maternal grandmother with chronic lymphocytic leukaemia.

She had no history of alcohol, smoking, or illicit drug use. In the emergency department she was given a second course of systemic antibiotics and scheduled for a follow-up appointment in the ophthalmology clinic nine days later.

In clinic, her visual acuity had drastically decreased to 6/60, the mass had increased in size and felt fluctuant, and her upgaze was now restricted (fig 1⇓).