Impact of head holder in reducing misregistration in the area of the head and neck on PET/CT.

Objectives In Whole-Body (WB) FDG PET/CT, spatial coregistration is sometimes compromised by involuntary patient motion. Motion artifacts are not uncommonly noted in the head and neck area. We evaluated the frequency of misalignment in the area of the head and neck on WB PET/CT and the impact of the use of head holder in minimizing such problems in our PET center.

Methods In our PET center, we routinely include the brain in the imaged field of view and use a head holder (PINESTAR Technology Inc.) to minimize involuntary motion. Such head immobilizer is a rigid, rubber-coated, concave semicircle in which the patients head fits securely into. We retrospectively reviewed 1188 consecutive PET/CT reports. A log was kept to record cases in which the reading physician noted head motion in the report. We also recorded Patients’ age, gender and body mass Index (BMI) for correlation purposes.

Results Of the 1188 PET/CT reports, head motion only occurred in 14(1%) cases (11 M, 3 F).The presence of head motion was not dependent on age, gender or BMI. Refer to Table 1 for further population comparison.

Conclusions In our PET/CT center, the head holder is well tolerated by patients. We conclude that head motion is relatively rare (1%) in our studied population, likely due to the successful use of head holder in our center. Further studies with larger sample size are needed to compare different head positioning schemes.