Category: Laparoscopic/ Robotic: Other

MP25-9 - 3-D volumetric assessment can predict split renal function precisely on the early post-operative period in robot-assisted partial nephrectomy

Sun, Sep 23
10:00 AM - 12:00 PM

Introduction & Objective : Robot-assisted partial nephrectomy (RAPN) is a standard surgery for patients with small renal cell carcinoma and contributes to sparing renal function. 99mTechnetium-mercapto acetyl triglycine (MAG3) scan has been used to evaluate post-operative split renal function. However, it takes a great deal of time and costs much. The aim of this study is to investigate whether CT volumetry could be alternative to MAG3 on pre-operative assessment of split renal function, and predict eGFR after RAPN


Methods : One hundred and four patients underwent RAPN from 2014 to 2018 in our institution. Those who did not perform thin slice CT (1-mm) or MAG3 scan, and those with follow up less than 3 months were excluded. Renal volume was automatically calculated by 3-D volume analyzer software. The correlation was evaluated using Pearson correlation coefficient and Bland-Altman plot. A 5-mm margin from tumor was excluded from cortex volume. Post-operative predicted eGFR was calculated using CT volumetry and compared with 3-months eGFR.


Results : Forty-two patients were included in this retrospective study. Median age was 60 years and the rate of male was 64%. Tumor bearing kidney cortex volume was 117.5 ml, and parenchymal volume was 155.3 ml, respectively. Pre-operative eGFR was 73 mL/min/1.73m2, 3-months postoperative eGFR was 67.8 mL/min/1.73m2, and the decrease in eGFR from pre-operative to post-operative 3-months was 9.2%. The cortex volume of 5-mm margin was 9.85 ml. A strong correlation was observed between MAG3 split renal function and cortex volume split renal function in Pearson correlation coefficient and Bland-Altman plot (r=0.82) (Figure 1). The predicted eGFR calculated by cortex volume was correlated with post 3-months eGFR (r=0.901) (Figure 2).


Conclusions : CT volumetry with 3-D technique is equivalent to MAG3 in determining split renal function, and can predict postoperative renal function after RAPN equally accurately and more quickly.

Yosuke Mitsui

Medical staff
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Takuya Sadahira

Clinical Fellow
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Takuya Sadahira M.D.
2011-2013 Resident, Okayama University Hospital, Japan
2013-2016 Resident, Department of Urology, Okayama University Hospital, Japan
2016-present Clinical Fellow, Department of Urology, Okayama Medical Hospital, Japan

Motoo Araki

Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Yasuyuki Kobayashi

asisstant professor
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Yuki Maruyama

graduate student
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

I am a urologist at Okayama university in Japan. Thank you for your kindness.

Shingo Nishimura

assistant professor
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Koichiro Wada

assistant professor
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Ryuta Tanimoto

assistant professor
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Masami Watanabe

Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Toyohiko Watanabe

associate professor
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan

Yasutomo Nasu

professor
Department of Urology; Okayama University Graduate School of Medicine; Okayama, Japan
Okayama, Okayama, Japan