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Editor,—Lipid granuloma of the lid and anterior orbit can occur in various conditions.1-6 We present a 33 year old woman with an indurated inflammatory swelling at the medial canthus 30 years after a dacryocystitis on the same side. Histologically the lesion was identical to those that have been described as a reaction to paraffin from displaced ointments.7 The lipid in our case, however, was analysed as a mixture of triglycerides corresponding to a substance that was previously used as a contrast material for dacryocystography. To our knowledge, this is the longest time span reported to date between the application of a lipid based material and the development of a lipogranulomatous reaction.
A 33 year old white woman presented with a painless red swelling of the medial left lower lid (Fig 1A) that had been present for several weeks. There was an obstruction of both lower and upper canaliculus and also mild oedema of the upper lid. On palpation, the swelling presented as a remarkably firm subcutaneous mass extending deep into the medial canthal area. Otherwise, all ocular findings were normal. The patient's previous ocular history was unremarkable apart from a left sided refractory dacryocystitis at age 3 that had been investigated and treated at another university eye department. The parents had documented the lesion photographically but unfortunately the chart was no longer available. Ultrasonography of the suspicious area revealed a dense homogeneous infiltration within the subcutaneous tissue while on computed tomograph scan no definite tumour was seen. With the presumed diagnosis of dacryocystitis, topical and systemic antibiotics were given but no improvement was noted. A full clinical examination including extensive laboratory investigations did not reveal any evidence of an underlying systemic disease or immunoregulatory abnormalities. Eventually a diagnostic biopsy revealing firm yellowish tissue (Fig 1B) was performed mainly to rule out lymphoma or a metastasis.
Histopathology showed muscle and fibrous tissue with numerous lipid vacuoles of different sizes (Fig 1C), surrounded by multinucleate giant cells and a dense inflammatory cell infiltrate. These were features consistent with the so called paraffin granuloma that has been described after endonasal sinus surgery and after injection of ointment into the lacrimal drainage system.7 It was decided to surgically remove as much of the tumour as possible which proved difficult because it extended around the medial canthus up into the upper lid and back into the orbit temporally. However, wound healing was without any complications, and the cosmetic result was excellent. On repeat probing, the canaliculus was now patent, and no recurrence was seen up to 2 years after the surgery.
In contrast with our histopathological expectations, a biochemical analysis of the excised tissue using infrared, mass, and nuclear magnetic resonance spectroscopy showed the extracted lipid to be an accumulation of triglyceride esters which mostly consisted of oleate and to a lesser degree of palmitate and stearate (2.5 mg versus 0.16 mg in non-affected control tissue).
This patient presented with a lipid-rich lesion similar to the so called paraffin granuloma which represents an inflammatory reaction to exogenous lipid.7Usually, exogenous lipid gets access into the tissue in the form of ointments used in or in close vicinity to the eye.7 8 In contrast with paraffin, however, the triglyceride esters that were analysed in our patient are not usually present in ophthalmic ointments. Triglycerides are rather a constituent of naturally occurring lipids and can be expected—for example, in fat necrosis after trauma. Our patient did not exhibit any features of a pre-existing lipomatous lesion such as, for example, a lipodermoid; moreover, there was no history of trauma or mechanical irritation. Thus, the most likely explanation for the presence of a lipogranuloma remains a “complication” from the treatment of her dacryocystitis 30 years ago. Various lipid based substances have been used for rinsing of, and instillation into, the canaliculus or lacrimal sac. These ointments, however, are usually also based on paraffin or Vaseline.5-9 Other lipid based materials have been employed as contrast material for viewing the lacrimal passage. One of the substances that has been commonly used for contrast dacryocystography is Lipiodol10, an iodised poppy seed oil which is a characteristic mixture of glyceric esters of various fatty acids including mainly oleic, linoleic, linolenic, palmitic, and stearic acid (information from Byk Gulden, Konstanz). Thus, the lipid composition of Lipiodol corresponds remarkably well to the mixture that was analysed in our specimen. The iodine present in the original substance can be expected to have been removed and transferred to the thyroid, and, with endogenous fat and ointments exhibiting somewhat different components, there is convincing evidence that Lipiodol can indeed be regarded as the initiating agent.
Similar problems after instillation of other lipid based substances into the lacrimal drainage system5-9 and one case of a granulomatous inflammation initiated by the application of a lipid based contrast medium to the orbit3 have been reported but the time between the original “insult” and the development of an inflammatory reaction was always much shorter. This suggests that, in our case, a minor injury to the canaliculus or lacrimal sac might have occurred, allowing only a very small amount of lipid based material to reach the surrounding tissues and cause a self propagating inflammatory process. As triglycerides are much more similar to human body fat than paraffin, one could speculate that this might further help to explain the unusually long time lapse between the primary application and the clinically relevant granulomatous reaction seen in our patient.
We are very grateful to Dr S Moss, Novartis, Switzerland, for performing the biochemical analysis.