The skinline is the ultrasonic penetration depth corresponding to the skin / transducer interface on the display.

(TOF) Time of flight is a ultrasound technique used for calculating of the distance to a target by using the timing of the returning echo from the target and the speed of sound in the medium between the target and the sensor. Time of flight is used in echo location and ultrasonic flowmeters.

A flowmeter derives an accurate measure of the transit time ; transit time (or time of flight) is the difference in time for an ultrasonic pulse to travel with the direction of flow and against it. With bi-directional illumination it is the time taken for an ultrasound pulse to travel from one transducer to another. This time is used to measure blood flow rate. The difference between the upstream and downstream measured transit times calculates the volume flow.

See also Echo Ranging.

The transorbital window allow to insonate ophthalmic artery and ipsilateral carotid siphon through the eye. It is also possible to use the transorbital entrance to scan the middle and anterior cerebral arteries, if it is impossible through the transtemporal window.
The patient is asked to remove any contact lenses prior to examination and is instructed to close the eyes. The power output of the Doppler instrument has to be decreased to 10-20% to reduce the ultrasonic exposure of the eye.

See also Transcranial Doppler, Ultrasound Safety.

Ultrasonography is another term[aka: sonography] used to describe the practice of using ultrasound technology for diagnostic imaging. It is synonymous with sonography and signifies the process of capturing ultrasound images, regardless of the body part or condition being examined. Ultrasonography is widely utilized in various medical imaging specialties, including obstetrics and gynecology, cardiology, radiology, urology, and many others. It has proven to be particularly valuable in obstetric imaging, allowing healthcare providers to monitor the growth and development of a fetus during pregnancy.
Ultrasonography uses the reflections of high-frequency sound waves to construct an image of a body organ. These ultrasonic waves are generated by a quartz crystal and are reflected at the interface between different tissues. The transmission and reflection of these high-frequency waves are displayed with different types of ultrasound modes.
See also sonogram, sonography, ultrasound imaging.