From the total of 657 patients who visited the Urology Department for acute flank pain, who were diagnosed with ureteral stones, and who underwent UECT from January 2009 to July 2011, we retrospectively analyzed 92 cases that were treated with URS. Patients who experienced other treatments such as ESWL or preoperative insertion of a double J stent were excluded from our study.
The UECT images that indicated ureteral stones were confirmed by a radiologist and were then examined for findings such as hydronephrosis or hydroureter, tissue rim signs, periureteral fat stranding, and perinephric fat stranding [5 (link)-7 (link)]. The hydronephrosis, rim sign, periureteral fat stranding, and perinephric fat stranding identified on the UECT were divided into four categories according to severity (none, mild, moderate, and severe). We classified the degree of hydronephrosis in reference to the grade of vesicoureteral reflux. Cases were defined as absent when hydronephrosis was not indicated by CT, mild when the intrarenal pelvis was prominent or with mild dilatation of the ureter, moderate for intrarenal pelvis or mild ureter dilatation, and severe for marked dilatation of the collecting system.
A positive tissue rim sign was defined as annular soft tissue attenuation (20 to 40 Hounsfield units) caused by an edematous ureteral wall surrounding the stone [8 (link)]. This diagnosis was divided into four categories: absent when the rim sign was not present, mild for soft tissue attenuation with a diameter of <2 mm, moderate for a diameter of 2 to 4 mm, and severe when the diameter was >4 mm. Perinephric fat stranding was defined as linear areas of soft tissue attenuation in the perinephric space [9 (link)]. Cases without fat stranding were categorized as none; cases with fat stranding were categorized as mild when a few thin strands were visible, severe when many thick strands were visible, and moderate when stranding findings were between mild and severe (Fig. 1 ).
Ureteroscopic findings were classified at the point of the mucosal edema and bleeding during URS. The mucosal edema findings were divided into 4 classifications (A, none; B, mild; C, moderate; and D, severe), which are indicated inFig. 2 . Bleeding during URS was divided into 4 groups (A, none; B, mild; C, moderate; and D, severe) by a single urologist and is indicated in Fig. 3 .
The data were analyzed to determine whether these ureteroscopic findings (mucosal edema, bleeding) could be predicted with the CT findings described earlier (hydronephrosis, rim sign, periureteral fat stranding, and perinephric fat stranding). Linear-by-linear analysis was used for categorical variables and a value of p<0.05 was considered statistically significant. IBM SPSS ver. 18.0 (IBM Co., Armonk, NY, USA), linear-by-linear, and Fisher exact tests were used.
The UECT images that indicated ureteral stones were confirmed by a radiologist and were then examined for findings such as hydronephrosis or hydroureter, tissue rim signs, periureteral fat stranding, and perinephric fat stranding [5 (link)-7 (link)]. The hydronephrosis, rim sign, periureteral fat stranding, and perinephric fat stranding identified on the UECT were divided into four categories according to severity (none, mild, moderate, and severe). We classified the degree of hydronephrosis in reference to the grade of vesicoureteral reflux. Cases were defined as absent when hydronephrosis was not indicated by CT, mild when the intrarenal pelvis was prominent or with mild dilatation of the ureter, moderate for intrarenal pelvis or mild ureter dilatation, and severe for marked dilatation of the collecting system.
A positive tissue rim sign was defined as annular soft tissue attenuation (20 to 40 Hounsfield units) caused by an edematous ureteral wall surrounding the stone [8 (link)]. This diagnosis was divided into four categories: absent when the rim sign was not present, mild for soft tissue attenuation with a diameter of <2 mm, moderate for a diameter of 2 to 4 mm, and severe when the diameter was >4 mm. Perinephric fat stranding was defined as linear areas of soft tissue attenuation in the perinephric space [9 (link)]. Cases without fat stranding were categorized as none; cases with fat stranding were categorized as mild when a few thin strands were visible, severe when many thick strands were visible, and moderate when stranding findings were between mild and severe (
Ureteroscopic findings were classified at the point of the mucosal edema and bleeding during URS. The mucosal edema findings were divided into 4 classifications (A, none; B, mild; C, moderate; and D, severe), which are indicated in
The data were analyzed to determine whether these ureteroscopic findings (mucosal edema, bleeding) could be predicted with the CT findings described earlier (hydronephrosis, rim sign, periureteral fat stranding, and perinephric fat stranding). Linear-by-linear analysis was used for categorical variables and a value of p<0.05 was considered statistically significant. IBM SPSS ver. 18.0 (IBM Co., Armonk, NY, USA), linear-by-linear, and Fisher exact tests were used.
