Ultrasound findings in horses with severe eyelid swelling, and recognition of acute dacryoadenitis: 10 cases (2004-2010).

OBJECTIVE: To report the sonographic findings, treatment, and outcome of horses with severe eyelid swelling, to describe the sonographic appearance of enlarged lacrimal glands, and to describe the clinical features of acute dacryoadenitis.
MATERIALS AND METHODS: Medical records of all horses with severe eyelid swelling that underwent an ultrasound evaluation of the globe and periorbital structures from 2004-2010 were examined. Cases were limited to those in which the eyelid swelling was so severe that the globe could not be visualized.
RESULTS: Ten horses met the criteria for inclusion in the study. All cases were unilateral and acute. Marked enlargement of the lacrimal gland was found in five cases, and supported the diagnosis of acute dacryoadenitis. Eyelid abscessation was found in three horses, accompanied by mild to moderate lacrimal gland enlargement in two of the three. Enlarged lacrimal glands were slightly heterogeneous in appearance and could be differentiated from an abscess by imaging the protrusion of the gland from beneath the supraorbital rim. Only two cases of severe eyelid swelling were soley traumatic.
CONCLUSIONS: Severe eyelid swelling was often associated with dacryoadenitis and/or eyelid abscessation. The detection of marked lacrimal gland enlargement in horses with an acute onset of severe painful eyelid swelling is consistent with a diagnosis of acute dacryoadenitis. Ultrasonographic evaluation of eyelid swelling of any degree is warranted to determine if enlargement of the lacrimal gland, etiology notwithstanding, is an underlying or contributing cause.