Longitudinal stone diameter on coronal reconstruction of computed tomography as a predictor of ureteral stone expulsion in medical expulsive therapy.
OBJECTIVE
To evaluate stone diameter and ureteral dilation using computerized tomography as a predictor of ureteral stone expulsion after medical expulsive therapy.


METHODS
We retrospectively reviewed the records of 328 patients with symptomatic ureteral stones <10 mm on axial computerized tomography images, who were treated with alpha blockers for 2 weeks. Computerized tomography scans were also performed 2 weeks after medical expulsive therapy to confirm ureteral stone expulsion. Patients were divided into upper ureteral stones and lower ureteral stones above and below the iliac vessels, respectively. Transverse stone diameter and longitudinal stone diameter were defined as the largest stone diameter determined on the axial and coronal computerized tomography images, respectively. Ureteral diameter was determined on one computerized tomography slice proximal to each ureteral stone on axial computerized tomography images, and the ratio of ureter-to-stone diameter was defined as ureteral diameter divided by transverse stone diameter.


RESULTS
Among 328 patients, the stone expulsion rate was 44.1% in 145 upper ureteral stones and 69.4% in 183 lower ureteral stones. Transverse stone diameter, longitudinal stone diameter, ureteral diameter, and the ratio of ureter-to-stone diameter were significantly lower in patients with ureteral stone expulsion in upper ureteral stones and lower ureteral stones (P < .001 for all parameters). Logistic regression analysis revealed that only longitudinal stone diameter was a significant predictor of stone expulsion in patients with upper ureteral stones (odds ratio 0.580, P = .040) and lower ureteral stones (odds ratio 0.415, P = .012).


CONCLUSIONS
Longitudinal stone diameter was a significant predictor of stone expulsion in patients with upper ureteral stones and lower ureteral stones after medical expulsive therapy. Measurement of stone diameters in coronal reconstruction may help to better choose a patient who is suitable for medical expulsive therapy.
Department of Urology, CHA Bundang Medical Center, CHA University, Seongnam, Korea. seung102@cha.ac.kr
Seung Ryeol
SR
Lee
Hwang Gyun
HG
Jeon
Dong Soo
DS
Park
Young Deuk
YD
Choi
D058668:Adrenergic alpha-1 Receptor Antagonists / Q000627:therapeutic use; D000328:Adult; D000368:Aged; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D009929:Organ Size; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D013449:Sulfonamides / Q000627:therapeutic use; D000077409:Tamsulosin; D036542:Tomography, Spiral Computed; D016896:Treatment Outcome; D014513:Ureter / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D014514:Ureteral Calculi / Q000000981:diagnostic imaging* / Q000188:drug therapy; D055815:Young Adult
D058668:Adrenergic alpha-1 Receptor Antagonists; D013449:Sulfonamides; D000077409:Tamsulosin