Diagnostic potential of three-dimensional ultrasound-based virtual cystoscopy: an experimental study using pig bladders.
OBJECTIVE
We sought to investigate the feasibility of 3-dimensional ultrasound (3D US)-based virtual cystoscopy in experimentally designed bladder phantoms using pig bladders.


METHODS
Ten bladder phantoms with simulated polypoid tumors of different sizes were constructed to provide 3D US-based virtual cystoscopic images. The simulated polypoid tumors were divided by their location into 2 groups: group 1 included the polyps on the anterior and posterior walls, and group 2 included those on the remaining 4 walls. Two genitourinary radiologists independently interpreted the virtual cystoscopic images, with a consensus reached for cases with discrepant results.


RESULTS
In a consensus reading, 3D US-based virtual cystoscopy detected 44 (91.7%) of 48 polypoid lesions. All lesions (n = 4) with false-negative results were 5 mm or smaller in diameter, and so the detection rate was 81.8% (18/22) for lesions 5 mm or smaller whereas it was 100% (26/26) for lesions larger than 5 mm. The detection rate for group 1 (93.8%) was not significantly different from that for group 2 (90.6%; P = 1.000). There were 7 false-positive lesions. Of these, 5 lesions were seen in group 1, and reverberation artifacts were the most common source of these errors (n = 4). Blind areas were present in 19 (31.7%) of 60 virtual cystoscopic images and were seen only in group 2. The differences in the false-positive rate and the incidence of blind area were statistically significant between both groups (P = 0.036, P = 0.00008, respectively).


CONCLUSIONS
3D US-based virtual cystoscopy may have diagnostic potential in the detection of polypoid bladder tumors.
Moon
Min Hoan
MH
Department of Radiology, Cheil General Hospital and Women's Healthcare Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Kim
Seung Hyup
SH
Lee
Young Ho
YH
Cho
Jeong Yeon
JY
Jung
Sung Il
SI
Park
Seong Ho
SH
Son
Kyu Ri
KR
D000818:Animals; D003558:Cystoscopy; D021621:Imaging, Three-Dimensional; D019047:Phantoms, Imaging; D011127:Polyps / Q000175:diagnosis* / Q000000981:diagnostic imaging; D013552:Swine; D014463:Ultrasonography; D001743:Urinary Bladder / Q000000981:diagnostic imaging*; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis*