B73.02

Clinical Causes: Infection with the parasitic worm Onchocerca volvulus, transmitted through the bites of infected blackflies (Simulium species). Repeated exposure to infected blackflies, often in regions near fast-flowing rivers and streams where blackflies breed. Development of onchocercal nodules and microfilariae in the eyes that trigger inflammatory responses. Progression of chronic inflammation leading to tissue damage within the eye, affecting the optic nerve and other structures. In some cases, immune system reactions may contribute to the eye damage associated with onchocerciasis.

Key Symptoms: Visual disturbances, such as blurred vision or seeing floaters. Progressive loss of peripheral vision, which can eventually lead to tunnel vision. Light sensitivity and eye discomfort in early stages. White or cloudy sclera (the white part of the eye), which may involve nodules. Presence of microfilariae in ocular tissues detected during examination. Signs of increased intraocular pressure, especially in cases progressing to glaucoma. In advanced stages, significant vision loss or blindness.

Diagnosis Path: Slit-lamp examination to assess eye structures, look for nodules, microfilariae, and signs of inflammation. Visual field testing to detect peripheral vision loss indicative of glaucoma. Tonometry to measure intraocular pressure levels. Serologic tests or skin snips to identify microfilariae or antibodies against Onchocerca volvulus. Ocular imaging techniques such as fundus photography or optical coherence tomography (OCT) for detailed assessment of optic nerve health. Consideration of patient history, including exposure to endemic areas and timing of symptom onset.

Treatment Protocols: Antiparasitic medications such as ivermectin to reduce microfilarial load and prevent disease progression. Anti-inflammatory treatments to control ocular inflammation and minimize tissue damage. Medications to lower intraocular pressure, potentially including eye drops, oral medications, or laser therapy, to treat glaucoma. Regular eye monitoring to track disease progression and response to therapies. Surgical interventions like trabeculectomy or implanting drainage devices in advanced glaucoma to preserve vision. Supportive care such as visual aids and rehabilitation for individuals with vision loss.