Microphakia/Lens Coloboma

Microphakia is a congenital condition in which an animal is born with an abnormally small lens that is prone to dislocation. It may occur in an otherwise normally developed globe or together with microphthalmia. Microphakia may also be associated with spherophakia, a rounded lens. It is seen more often in dogs and is extremely rare in cats. The source reports it somewhat more frequently in Beagles, Doberman Pinschers, and Miniature Schnauzers, often together with other ocular abnormalities.

Lens coloboma is a rare congenital abnormality caused by improper prenatal lens development. It may occur alone or with other ocular defects such as microphakia, iris coloboma, or retinal coloboma.

Treatment

Diagnosis is made by biomicroscopic examination and, if necessary, ultrasonography. No treatment is performed unless lens luxation develops, in which case the lens is surgically removed.

Microphakia in a cat. A small cataractous lens and elongated ciliary processes, red arrow, are visible.

Lens coloboma, arrow.

Lens coloboma and posterior subcapsular cataract in a cat.

Adapted from the Atlas of Ocular Diseases in Dogs and Cats by Dr. Siniša D. Grozdanić and colleagues. © Animal Eye Consultants of Iowa. The text and clinical images on this page are original content from the authors' own clinical practice and research, and may not be reproduced, distributed, or repurposed without permission.

Think your pet may have microphakia/lens coloboma?

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