SAEVA Congress 2018 Proceedings | 12-15 February 2018 | ATKV Goudini Spa
Cranial mediastinal neoplasia
Soft tissue masses may be imaged in the cranial mediastinum and are most common
in horses with thoracic lymphosarcoma although may be detected in horses with
mesothelioma, melanoma or hemangiosarcoma. Lymphosarcoma masses in the
cranial mediastinum are usually associated with large pleural effusions, making these
large soft tissue masses easier to image. These masses usually occupy the entire
cranial mediastinum, obliterating the normal thick membranous division imaged in
horses with pleural effusion. The mass usually displaces the right apical lung lobe
dorsally; the heart caudally, and therefore, can be imaged from either side of the thorax
in the 3rd ICS. In most horses only one large mass can be imaged which may have a
homogeneous or heterogeneous ultrasonographic appearance. This mass may be
imaged extending dorsally and cranially towards the thoracic inlet, and up the neck with
cervical lymph node involvement.
Cranial mediastinal mass (lymphosarcoma)
Diaphragmatic Hernias
Diaphragmatic hernias are likely to result in viscera occupying a portion of the caudal
mediastinum or caudal thorax.
A diaphragmatic hernia can be diagnosed
ultrasonographically when viscera is imaged in the thoracic cavity immediately adjacent
to the lung, or floating within pleural fluid without the diaphragm separating the thoracic
and abdominal viscera.
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