Inspired by the mysterious and salacious Jon Mishoe.
Trying to explain ultrasound via text just won’t work. Instead I will attempt to describe various ultrasound concepts and possibilities and I encourage you to grab ultrasound faculty for hands-on demonstrations if the clinical scenario is appropriate.
Given the small amount of subcutaneous tissue and small surface area, the hand is a particularly difficult body part to ultrasound. By submerging the hand in a bucket of water you can obtain much clearer ultrasound images identifying the joints, bones, tendons, cysts, neuromas, and dislocations. Foreign bodies the size of a bee’s stinger can be visualized and extracted using this technique.
Ultrasound can be used to visualize the pupil constrict under a closed eyelid when light is applied to the contralateral open eye (assessing for APD). We are thus able to obtain a pupillary exam despite periorbital hematomas, chemosis, and blepharedema.
Neurosonology is the ability visualize vascular flow to the brain. In some areas on the skull, the bones are relatively thinner and permit sufficient penetration of the ultrasound. These areas are called acoustic windows. The four commonly employed acoustic windows in adults are – temporal, orbital, suboccipital, and submandibular. Though difficult, flow to various intracerebral arteries can be identified on ultrasound thus evaluating for intracranial thromboembolic disease.
Ultrasound can be also be used to evaluate for proximal aortic dissection. Using the parasternal long view as well as a view from the suprasternal notch one can well visualize the aortic root and identify a flap in the case of dissection. Especially in the hands of the inexperienced this does not rule out aortic dissection however it can effectively be used to rule it in as a diagnosis.
Clinicians can, with a high level of accuracy, use point-of-care ultrasound to identify fractures when x-ray is not available or undesirable. Consider it for your pregnant patients or for the wailing child that will not stay still for a clear xray image.
Especially in young, thin kids, ultrasound can be used to evaluate for appendicitis…ask Jim Tsung the proper technique next time you are working with him on shift.