Novel Water Bath Method for Ultrasound Imaging of Distal Extremities

Water baths can greatly enhance point of care ultrasound imaging of the distal extremity and improve patient care in a number of clinical scenarios (1, 2, 3). Traditional water baths involve placement of the distal extremity... [ view full abstract ]

Water baths can greatly enhance point of care ultrasound imaging of the distal extremity and improve patient care in a number of clinical scenarios (1, 2, 3). Traditional water baths involve placement of the distal extremity into a bath of water, usually a large flat pan, and submerging the ultrasound probe into this water bath in the horizontal plane (4). This improves the transmission of sound waves and subsequently increases image quality. The area of interest must then be positioned directly under the ultrasound probe in the horizontal plane, requiring some manipulation of the patient. This manipulation can be limited due to pain or difficulty moving an area of interest in line with the probe due to normal anatomic restrictions of the joints. Our new method of water bath imaging removes the element of manipulating the patient into the correct position by imaging through the side of a flat walled, column shaped, thin plastic container without submerging the ultrasound probe. This allows for 360 degrees of imaging freedom and as a result much easier image acquisition. Image quality in traditional water baths rely on the steadiness of the operator’s hand while holding the probe above the imaging area of interest and also on the patient’s steadiness holding in a fixed position. In our method of water bath imaging the probe is held against the external wall of the water bath; providing superior probe stabilization and more consistent, higher quality images. This method also improves stabilization of the area of interest by allowing the patient to stabilize the distal extremity against the bottom of the water bath column; reducing patient movement and again contributing to the generation of more consistent, higher quality images. Additionally this method requires a small volume of water that is easier to transport than the large, shallow baths typically employed for traditional water bath imaging; making ultrasound water bath imaging more convenient to apply in the busy clinical environment. Essentially this novel method of water bath imaging allows users to achieve the advantages of increased image quality, while correcting for the limitations of traditional water baths by providing superior stabilization of the probe and patient, and greater freedom of imaging in 360 degrees with minimal manipulation of patient position.

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