Radiography (Lond). 2020 Jul 26:S1078-8174(20)30126-7. doi: 10.1016/j.radi.2020.07.002. Online ahead of print.
INTRODUCTION: The protocol for preparation of computed tomography urography (CTU) examinations at our hospital was changed in 2013 to improve the quality of urinary bladder filling in the excretory phase. The aim of this study was to evaluate the quality of urinary bladder filling on CTU after different doses of furosemide were administered to patients with macroscopic hematuria.
METHODS: The cohort was 215 patients who underwent elective CTU due to macroscopic hematuria between 2014 and 2018. 5 mg furosemide were administrated to 100 patients, 2.5 mg to 100 patients and 0 mg to 15 patients. Contrast medium layered bladders were excluded, leaving 193 patients: 92, 89 and 12 in each group. Urinary bladder volume was calculated in corticomedullary (CMP) and excretory phase (EP). Bladder distension was classified as satisfactory or not. Attenuation of bladder content in EP was noted.
RESULTS: Average volume in EP was 370 ± 224 ml (28-1052) after 5 mg furosemide, 274 ± 120 ml (43-628) after 2.5 mg and 180 ± 104 ml (53-351) after 0 mg. 85% of the bladders were satisfactory distended after 5 mg, 80% after 2.5 mg and 58% after 0 mg. Average attenuation was 266 ± 89 HU (103-524) after 5 mg, 362 ± 156 HU (118-948) after 2.5 mg and 761 ± 331 HU (347-1206) after 0 mg. The differences in volume and attenuation were significant.
CONCLUSION: 5 mg furosemide is preferred rather than 2.5 mg in preparation for CTU examinations of patients with macroscopic hematuria. There was no difference between the doses concerning rate of satisfactory bladder distension, but the higher dose resulted in larger bladder volume and more suitable attenuation of bladder content.
IMPLICATIONS FOR PRACTICE: Development of CTU-image quality could improve bladder cancer diagnostics.