Image Quiz: Ophthalmology—A rockfish with a bulging eye
This fish-only disease is called ocular gas bubble disease. There are several possible causes, all related to an abnormal partial pressure of gases (nitrogen or oxygen) in the water. This leads to formation of gas bubbles in the eye (and other parts of the body as well). The causes include an overt presence of algae in the tank, abnormalities within the water pipe system, chronic inflammation, and trauma. There are mild and severe forms of the disease. In cases of severe disease, lens luxation, cataract formation, uveitis, vision loss with retinal detachment, and severe buphthalmia are often found, as well as DIC (disseminated intravascular coagulation). The removal of the gas bubbles through a limbal paracentesis (under sedation and topical anesthesia) and investigation of the primary cause of the disease can usually prevent recurrence and worsening of the disease.