Development of an Interactive GUI Tool for Thyroid Uptake Studies using Gamma Camera

Acquisition and Imaging

Thyroid uptake scan study was implemented on 30 cases with definite or suspected disease (4 male and 26 female patients, mean age) after intravenous injection of 2 milli-curies of technetium-99m pertechnetate. Data Acquisition was done using Siemens dual-head variable angle gamma camera with a parallel hole collimator placed on the (anterior) detector 1.The patient is positioned in supine with his head tilted back and neck in hyper extended position, to ensure the risibility of the thyroid region. The Acquisition parameters used were as follows: anterior view, 128X128 with a zoom factor of 1.78.

Data of each patient consists a set of four 16-bit static Dicom images. These delayed Static images were obtained observing a delay of 2 to 3 hrs past the post syringe. The imaging procedure is as follows:

• 1.

  A full Syringe completely loaded with Tc-99m is imaged for one minute;

• 2.

  After injecting the radio tracer, the thyroid is imaged for 10 minutes;

• 3.

  Post the injection, empty syringe (having small amount of tracer still after injection) is imaged for one minute;

• 4.

  Vein, where tracer is injected (Anticubital) is imaged for one minute.

The Significance of taking the values of Full syringe, Empty Syringe and Anticubital is that it helps in calculating the total uptake in the thyroid region. It can explained as follows:

• •

  Full syringe is the total available tracer that has to be injected into the body. The total counts of the syringe gives the total number of counts that were given into the body;

• •

  Anticubital measures the amount of tracer that was still present in the vein of the patient where the tracer was injected;

• •

  Empty Syringe measures the amount of tracer still leftover in the syringe after the injection;

• •

  The summation of anticubital and empty syringe provides the information of the uptake that was not injected into the body. The difference between Full Syringe counts and the above summation provides the actual uptake of the tracer by the human body;

• •

  The Background counts are subtracted from the thyroid uptake to ensure that the counts of organs other than thyroid are filtered.