A comparison of the diagnostic performance of half-time SPECT and multiplanar pelvic bone scan in patients with significant bladder artifacts.
OBJECTIVE
The objective of this study was to evaluate the diagnostic performance of half-time single-photon emission computed tomography (SPECT) in the interpretation of bone scans in patients with bladder artifacts in comparison with multiplanar imaging. We also investigated whether SPECT could reduce the radiation dose to nuclear medicine personnel and shorten the acquisition time.


METHODS
Data from 29 patients with significant bladder artifacts were assessed by two nuclear medicine physicians. The presence or absence of pelvic bone lesions was individually interpreted with both techniques, multiplanar imaging and half-time SPECT, using a three-point pelvic score as follows: 0=definitely no lesion, 1=indeterminate, 2=definite positive lesion. A comparison of the diagnostic performances between the two techniques was made. The radiation dose to personnel and acquisition time were also investigated.


RESULTS
Using half-time SPECT, the incidence of studies interpreted without interference from bladder artifacts (artifact-free image) was 100% on both patient-based and lesion-based analyses of 29 patients, whereas multiplanar imaging revealed incidences of 52 and 90% on patient-based and lesion-based analyses, respectively. Ninety percent of technologists and 58% of assistants received 1 µSv/case radiation dose while performing multiplanar imaging. Only 10% of technologists received 1 µSv/case and none of the assistants received a detectable radiation dose from SPECT. The SPECT technique could also reduce the examination time, particularly when positioning time was included.


CONCLUSIONS
Half-time SPECT can significantly improve the diagnostic confidence of interpreting equivocal pelvic lesions in patients with bladder artifacts, compared with multiplanar imaging. This technique also provides lower radiation dose to nuclear medicine staff and requires shorter examination time.
Department of Radiology, Division of Nuclear Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. stanyalu@hotmail.com
Tanyaluck
T
Thientunyakit
Tarit
T
Taerakul
Pachee
P
Chaudakshetrin
Kritaya
K
Ubolnuch
Krittiya
K
Sirithongjak
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D015588:Observer Variation; D010384:Pelvic Bones / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D001743:Urinary Bladder / Q000000981:diagnostic imaging