Sir,

Silicone oil is necessary for endo-tamponade in selected cases of retinal detachment. Oil granuloma is a recognised condition in which there is a granulomatous response to mineral oils in the body tissues. In the past, this has been a well-documented complication of breast augmentation surgery. We report a case of silicone oil leaking into the periorbital and retro-orbital tissues, causing increasing proptosis and red eye many years after retinal surgery.

Case report

A 54-year-old Caucasian male presented with a 6-month history of a red, ‘unsightly’, more prominent right eye. He had suffered trauma to this eye 40 years previously and developed cataract and retinal detachment 13 years ago. He underwent a lensectomy and vitrectomy with silicone oil insertion at that time. The eye had been blind since this surgery and he was lost to follow-up until this recent complication. He was a non-smoker and had no other medical history and was on no medication. On examination, the eye was divergent and proptosed with a large subconjunctival gelatinous mass medially and an opaque, vascularised cornea (Figure 1). There was no regional lymphadenopathy. A CT scan showed enhancement of the soft tissues, particularly around the right medial rectus (Figure 2a). There was coexisting unilateral axial myopia, which was confirmed on A-scan (axial length right eye was 29.97 mm and left eye was 24.92 mm). Biopsy of the subconjunctival mass revealed spaces of varying shape and size where silicone oil material had been lost during processing (Figure 2b). There was no evidence of tumour infiltration or foreign body material present and a relatively mild inflammatory reaction was observed. The pathological findings are consistent with leakage of silicone oil into the subconjunctival space and periorbital tissues. The patient was treated with enucleation and perioperatively glistening silicone oil globules were visible to the naked eye throughout the thickened peri- and retro-orbital tissues. The posterior globe sclera was markedly thinned and oil appeared to leak diffusely through this area.

Figure 1
figure 1

Clinical photograph showing gelatinous subconjunctival mass medially in the right eye.

Full size image
Figure 2
figure 2

(a) CT scan image showing proptosis of the right eye, unilateral myopia, and soft tissue enhancement particularly in the region of the medial rectus. (b) Histopathological picture showing spaces of varying shape and size where silicone oil material has been lost during processing. This contrasts with normal fat in the periorbital region, which would demonstrate lipid spaces of the same size histologically (haematoxylin and eosin (H&E) stain).

Full size image

Comment

Oil granuloma occurs when bulky mineral oils are injected into body tissues. Silicone oils were previously injected locally for breast augmentation and reported to cause granulomatous reactions requiring the removal of the granulomas between 3 and 20 years after the silicone injections.1 This case report describes the complication of silicone oil used for endo-tamponade leaking out of the eye to cause thickening of the peri-orbital tissues 13 years after the oil was inserted. There have been few reports previously of oil migrating out of the eye in other situations. It has migrated along the optic nerve into the brain in an AIDS patient who presented with a peripheral neuropathy 15 months after retinal surgery. Neuro-imaging revealed oil within the lateral ventricles and the intracranial segment of the optic nerve.2 It was believed that the oil infiltrated the tissues due to prolonged raised intraocular pressure.2 Nazemi et al3 reported a case where silicone oil migrated into the subconjunctival space and orbit through an Ahmed valve in an aphakic patient despite inferotemporal positioning of the valve to try to minimise this risk. Oil also drained through a Molteno implant into the subconjunctival space in an aphakic male.4 Further reports describe a patient in whom silicone oil caused ptosis after migrating into the eyelid 19 years after retinal surgery,5 and two patients who developed episcleral granulomas after silicone oil tamponade.6 Clinicians have described leakage of oil through the scleral entry ports5, 6 and the presence of post-operative ocular hypertension as pertinent factors leading to this complication.5 We recommend long-term follow-up of patients with intraocular silicone oil in view of this potential serious complication.