Sometime in the past few million years, collapse at the top of the cave and surface erosion created the natural entrance of Carlsbad Cavern. This opened previously hidden underground cave passageways to the world above for the first time.
The Society of Diagnostic Medical Sonography (SDMS) defines sonography as diagnostic medical procedure that uses high frequency sound waves (ultrasound) to produce dynamic visual images of organs, tissues, or blood flow inside the body. This type of procedure is often referred to as a sonogram or ultrasound scan.
In addition to working directly with patients, diagnostic medical sonographers keep patient records and adjust and maintain equipment. They also may prepare work schedules, evaluate equipment purchases, or manage a sonography or diagnostic imaging department (Bureau of Labor and Statistics, 2010).iagnostic medical sonographers use special equipment to direct high frequency sound waves into areas of the patient's body. Sonographers operate the equipment, which collects reflected echoes and forms an image that may be videotaped, transmitted, or photographed for interpretation and diagnosis by a physician.