Korean J Urol.  2013 Nov;54(11):772-777.

Predictive Value of Preoperative Unenhanced Computed Tomography During Ureteroscopic Lithotripsy: A Single Institute's Experience

• Kim S
• Choi SK
• Lee SM
• Choi T
• Lee DG
• Min GE
• Jeon SH
• Lee HL
• Chung JY
• Joh JH
• Yoo KH

Abstract

PURPOSE
Ureteroscopic stone removal is frequently used to remove ureteral stones. Mucosal edema and bleeding are the two most important obstacles to a successful operation. This study analyzed relationships between unenhanced computed tomography (UECT) findings and ureteroscopic findings to determine whether ureteroscopic results could be predicted preoperatively by using UECT imaging.
MATERIALS AND METHODS
From January 2009 to July 2011, 675 patients were diagnosed with ureteral stones through UECT. Among them, we retrospectively reviewed 92 cases of patients who underwent ureteroscopy (URS). We identified findings such as hydronephrosis, rim sign, periureteral fat stranding, and perinephric fat stranding on the UECT and then categorized these findings into four categories (none, mild, moderate, and severe) according to their severity. We also divided the URS findings of mucosal edema and bleeding into four categories (none, mild, moderate, and severe) and compared these findings with the UECT images.
RESULTS
A total of 92 study patients were included in this study: 59 were male and 33 were female patients. According to the location of the stone, 31 cases were classified as upper ureteral stones, 15 were midureteral stones, and 46 were lower ureteral stones. Hydronephrosis identified with UECT was correlated with the mucosal edema severity observed during URS (p=0.004). The rim signs identified with UECT were proportional to the grade of mucosal edema (p=0.010).
CONCLUSIONS
Hydronephrosis and rim signs observed during UECT can be used as a predictive factor for intraoperative mucosal edema in patients undergoing URS.

Keyword

Ureteral calculi; Ureteroscopy; X-ray computed tomography

MeSH Terms

Edema
Female
Hemorrhage
Humans
Hydronephrosis
Lithotripsy*
Male
Retrospective Studies
Tomography, X-Ray Computed
Ureter
Ureteral Calculi
Ureteroscopy

Figure

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  FIG. 1 Images taken from unenhenced computed tomography. Perinephric fat stranding was categorized according to its degree of perinephric fat stranding. A, none; B, mild; C, moderate; D, severe.

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  FIG. 2 Images taken during ureteroscopy. Mucosal edema was categorized according to its degree of mucosal edema. A, none; B, mild; C, moderate; D, severe.

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  FIG. 3 Images taken during ureteroscopy. Intraluminal bleeding was categorized according to its degree of intraluminal bleeding. A, none; B, mild; C, moderate; D, severe.

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