The patient must have nothing by mouth (NPO) 6 hours prior to the exam. The Radiologist will write the pre-operative orders. Pre-labs of CBC, PT, (PTT) may be ordered. The patient should continue all oral meds especially anti-hypertensive medications.
A chronograph is a specific type of watch that is used as a stopwatch combined with a display watch. A basic chronograph has an independent sweep second hand; it can be started, stopped, and returned to zero by successive pressure on the stem. Less simple chronographs use additional complications and can have multiple independent hands to measure seconds, minutes, hours and even tenths of a second.
A seismograph is only one tool scientists are using, in an attempt to LEARN how to predict volcanos and earthquakes. If the technique had already been developed, then many lives would have been saved in the last several years. What a seismograph detects is the movement of ground in the area of the instrument. They are pretty sensitive and can detect, even very slight movements, such as the passing of nearby automobiles, and, man made explosions many miles away.