The OR button is located in the plaque insertion controls group of the Prescription window.
Clicking this button opens the scheduled surgical procedure start time (OR time) dialog sheet. This is a modal dialog sheet which blocks its parent window until you exit the sheet.
This OR Time Sheet provides a method for specifying the scheduled surgical start time for plaque insertion and removal procedures. By default, the OR times are initialized to the plaque insertion and removal times as entered in the Rx Window. The controls in this sheet allow you to document any significant differences between the scheduled OR times and the actual plaque insertion or removal times.
Ideally, to best calibrate the required radionuclide source strengths, the times entered in the Rx Window should be the times at which the plaque holding the radioactive sources will actually be inserted and removed. In clinical practice, these times may be difficult to predict precisely.
Typically, the time delay between the scheduled surgical procedure start time (OR time) and plaque insertion or removal will be less than 1% of the overall implant duration in which case the OR times may optionally be used as approximations of the plaque insertion and removal times.
There may be occasions, however, for which the time delay between the scheduled surgical procedure start and plaque insertion or removal might become significant.
For example, a treatment preplan was designed for a 72 hour implant duration with plaque insertion and removal times estimated to be 8 AM. A complication occurs which delays plaque insertion until 10 AM. Due to scheduling conflicts, plaque removal could not also be delayed by 2 hours to compensate. The actual plaque removal was at 8:15 AM. The delivered implant duration was therefore 70.25 hours (instead of the intended 72 hours) which results in an approximately 2.5% underdose.
To document this in the final plan, in the Rx Window set the plaque insertion time to 10 AM and the removal time to 8:15 AM (without recalculating source strengths!), and use the OR Time sheet to make note of the scheduled OR times. Whenever an OR time differs from the plaque insertion or removal time the differences will be noted in the treatment plan.
If you document the OR start and plaque insert and removal times for many cases, you may eventually be able to predict these times in subsequent preplans.
Click OK to accept the currently displayed OR sheet settings and exit the dialog.