Ocular Dirofilariasis of the Eyelid: A Case Report and Systematic Review of the Literature

Background/Objectives: To present a case report of eyelid dirofilariasis and conduct a systematic review of the corresponding literature. Methods: A 79-year-old patient presented with a painless mass in the left upper eyelid of 2 months duration, which was complicated during the latter period by two episodes of recurrent periorbital edema extending to the left cheek. The ophthalmic examination did not reveal any other ocular or adnexal pathology. On MRI images, the lesion was depicted as a slightly heterogeneous solid mass with unclear borders and heterogeneous enhancement. Results: A complete surgical excision of the lesion was performed, as the possibility of malignancy could not be ruled out. The histopathological examination revealed visible cross-sections of a nematode helminth, further identified as Dirofilaria repens based on its specific microscopic morphological characteristics, which ultimately established the diagnosis of dirofilariasis. A review of the respective literature, including 117 published cases, is provided attempting to summarize the clinical and diagnostic characteristics of the ocular cases of dirofilariasis affecting in specific, the eyelids. Conclusions: Ocular dirofilariasis should be included in the differential diagnosis of every eyelid subcutaneous tumor-like nodule or cyst of unknown etiology. An in-depth familiarization with its particularities is required in any sense, especially in the forthcoming years, when the endemic regions of Dirofilaria will expand, encompassing previously unaffected geographical areas.