Ultrasonographic Examination of the Equine Neonate

Abstract

Diagnostic imaging can substantially augment physical examination findings in neonatal foals. Used in combination with radiography or as a stand-alone imaging modality, ultrasound evaluation of the thoracic and abdominal body cavities can be a high-yield diagnostic undertaking. Many of the conditions that afflict neonatal foals are highly amenable to sonographic interrogation, including pneumonia and other changes in the lungs associated with sepsis, systemic inflammatory response syndrome, multiple organ dysfunction, and prematurity; colic arising from medical and surgical causes; and urinary tract disorders. Sonographic imaging is not affected by intracavitary fluid accumulation and reveals abnormalities of soft tissue and bony origin.

Anatomical Assessment of the Thorax in the Neonatal Foal Using Computed Tomography Angiography, Sectional Anatomy, and Gross Dissections

“…In equine medicine, radiology has been the main imaging modality used to image the thorax of foals, but the superimposition of adjacent anatomical structures makes its interpretation difficult [7]. Nonetheless, an advanced imaging technique such as the ultrasound [8,9] has given to the equine practitioners the opportunity to obtain an accurate diagnosis. In addition, helical CTA has also been used in horses, but information is limited to reports on the head, spinal cord, musculoskeletal system, and lungs [10][11][12][13][14][15][16][17][18][19].…”

Preoperative computed tomographic evaluation of neonatal foals with rib fractures

“…Diplomates of the ACVIM performed the ultrasound examinations (Logiqe, GE Healthcare, Chicago, Illinois) using previously described techniques. 5 Clinicians examined the ribs in a long-axis view using linear or microconvex transducers at 6-10 mHz (clinician preference) focusing on the cranial and/or lateral aspects of the ribs. Clinicians performed the ultrasound examinations on non-anesthetized foals and they attempted to examine all ribs.…”

“…[1][2][3][4] These fractures may cause pulmonary contusion or lacerations of the diaphragm, pleura, lung, pericardium, heart, or intercostal vessels, depending on their location. 2,3,5 Consequences include respiratory distress, herniation of abdominal contents into the thoracic cavity, hemorrhage, hemothorax, pneumothorax, and death. 2,3,5 Although many foals with rib fractures are treated successfully with conservative, non-surgical management, surgical repair may be recommended in cases where damage to vital structures may occur.…”

“…2,3,5 Consequences include respiratory distress, herniation of abdominal contents into the thoracic cavity, hemorrhage, hemothorax, pneumothorax, and death. 2,3,5 Although many foals with rib fractures are treated successfully with conservative, non-surgical management, surgical repair may be recommended in cases where damage to vital structures may occur. 6 Internal fixation of rib fractures in neonatal foals has been associated with survival rates ranging from 50% to 100% (4/8, 12/14, 1/1, and 4/4 foals) in a short case series using a variety of techniques.…”

“…4 Ultrasonography is useful in confirming the diagnosis (which is often initially suspected based upon palpation of the ribs) and assessing the thoracic cavity, heart, and pericardium for hemothorax and hemopericardium. [3][4][5] However, the quality of ultrasound studies is limited by patient movement, patient respiration, and difficulty visualizing the ribs adjacent to the humerus. 4 Furthermore, ultrasonographic images are evaluated in real-time with only one or two ribs in the field of view at a time, so an accurate determination of exactly which ribs are fractured may be difficult.…”