TNOA Journal of Ophthalmic Science and Research

: 2020  |  Volume : 58  |  Issue : 4  |  Page : 316--317

Unilateral ophthalmomyiasis externa

Shruthy Vaishali Ramesh1, Prasanna Venkatesh Ramesh2, Ramesh Rajasekaran3, Meena Kumari Ramesh1,  
1 Department of Cataract and Refractive Surgery, Ophthalmology and Strabismus, Mahathma Eye Hospital Private Limited, Trichy, Tamil Nadu, India
2 Department of Glaucoma and Research, Ophthalmology and Strabismus, Mahathma Eye Hospital Private Limited, Trichy, Tamil Nadu, India
3 Department of Paediatric Ophthalmology and Strabismus, Ophthalmology and Strabismus, Mahathma Eye Hospital Private Limited, Trichy, Tamil Nadu, India

Correspondence Address:
Dr. Prasanna Venkatesh Ramesh
Mahathma Eye Hospital Private Limited, No.6, Seshapuram, Thennur, Trichy - 620 017, Tamil Nadu

How to cite this article:
Ramesh SV, Ramesh PV, Rajasekaran R, Ramesh MK. Unilateral ophthalmomyiasis externa.TNOA J Ophthalmic Sci Res 2020;58:316-317

How to cite this URL:
Ramesh SV, Ramesh PV, Rajasekaran R, Ramesh MK. Unilateral ophthalmomyiasis externa. TNOA J Ophthalmic Sci Res [serial online] 2020 [cited 2022 Dec 1 ];58:316-317
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Full Text

A 20-year-old male presented with foreign body sensation and redness in his left eye. On eversion of the lid, conjunctival congestion and a motile, translucent worm were noted, which depicted photo-aversion. The worm were removed and sent for histopathology. The prominent features of the Oestrus ovis larva were observed [Figure 1] with a segmented translucent body; white cephalopharyngeal skeleton; and characteristic curved, dark oral hooklets. Conjunctival ophthalmomyiasis is commonly caused by O. ovis (sheep bot fly).[1],[2] Ophthalmomyiasis externa should be a differential diagnosis in the cases of unilateral conjunctivitis, especially in those living near a farm.[3]{Figure 1}

Oestrus ovis belongs to the Class: Insecta, Order: Diptera and Family: Oestridae. It is the most common cause of human myiasis.[4]

The fly deposits hatched larvae, during flight on the moist surfaces such as nasal mucosa of sheep and cattle and accidentally human eyes. Man is an accidental host and hence the ocular myiasis in humans may be a rare condition. These larvae can penetrate intact skin and conjunctival mucus membrane, and manifest as ophthalmomyiasis.[5]

Ophthalmomyiasis can be classified into three types based on their location:[6] External Ophthalmomyiasis where larvae are present on the lids and ocular surface. It may present as conjunctivitis, preseptal cellulitis or keratouveitis. When there is penetration of larva into aqueous, iris, vitreous or sub retinal space it is called as internal ophthalmomyiasis. In orbital ophthalmomyiasis there is Involvement of ocular adnexa and optic nerve. It is the most destructive type.

It is known that internal ophthalmomyiasis and orbital ophthalmomyiasis are a sequelae of external disease, though it is very rare. But keeping in mind the possibility of such scenarios it is mandatory to do a thorough posterior segment evaluation during followup visits.[7]

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the legal guardian has given his consent for images and other clinical information to be reported in the journal. The guardian understands that names and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.


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