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Endoscopy 2025; 57(12): 1423-1424
DOI: 10.1055/a-2703-3919
Letter to the editor

Reply to Ancil et al.

Authors

  • Akinori Maruta 

    1   Gastroenterology, Gifu Prefectural General Medical Center, Gifu, Japan (Ringgold ID: RIN68266)

  • Takuji Iwashita 

    2   First Department of Internal Medicine, Gifu University Hospital, Gifu, Japan (Ringgold ID: RIN476117)

  • Tomotaka Saito 

    3   Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan (Ringgold ID: RIN13143)

  • Wataru Gonoi

    4   Radiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan (Ringgold ID: RIN13143)

  • Kensaku Yoshida

    1   Gastroenterology, Gifu Prefectural General Medical Center, Gifu, Japan (Ringgold ID: RIN68266)

  • Shunsuke Omoto 

    5   Gastroenterology and Hepatology, Faculty of Medicine, Kindai University Hospital, Osaka, Japan (Ringgold ID: RIN326473)

  • Mamoru Takenaka 

    5   Gastroenterology and Hepatology, Faculty of Medicine, Kindai University Hospital, Osaka, Japan (Ringgold ID: RIN326473)

  • Masahiro Tsujimae

    6   Division of Gastroenterology, Department of Internal Medicine, Kobe University, Kobe, Japan (Ringgold ID: RIN12885)

  • Atsuhiro Masuda

    6   Division of Gastroenterology, Department of Internal Medicine, Kobe University, Kobe, Japan (Ringgold ID: RIN12885)

  • Tsuyoshi Hamada

    3   Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan (Ringgold ID: RIN13143)
    7   Hepato-Biliary-Pancreatic Medicine, Cancer Institute Hospital, Japanese Foundation For Cancer Research, Tokyo, Japan (Ringgold ID: RIN13609)

  • Shinya Uemura

    2   First Department of Internal Medicine, Gifu University Hospital, Gifu, Japan (Ringgold ID: RIN476117)

  • Shogo Ota 

    8   Division of Hepatobiliary and Pancreatic Diseases, Department of Gastroenterology, Hyogo Medical University, Hyogo, Japan (Ringgold ID: RIN12818)

  • Hideyuki Shiomi

    8   Division of Hepatobiliary and Pancreatic Diseases, Department of Gastroenterology, Hyogo Medical University, Hyogo, Japan (Ringgold ID: RIN12818)

  • Kentaro Suda

    9   Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama, Japan (Ringgold ID: RIN13031)

  • Saburo Matsubara 

    9   Gastroenterology and Hepatology, Saitama Medical Center, Saitama Medical University, Saitama, Japan (Ringgold ID: RIN13031)

  • Sho Takahashi

    10   Gastroenterology, Graduate School of Medicine, Juntendo University, Tokyo, Japan (Ringgold ID: RIN12847)

  • Toshio Fujisawa 

    10   Gastroenterology, Graduate School of Medicine, Juntendo University, Tokyo, Japan (Ringgold ID: RIN12847)

  • Yuhei Iwasa

    11   Gastroenterology, Gifu Municipal Hospital, Gifu, Japan (Ringgold ID: RIN38226)

  • Keisuke Iwata

    11   Gastroenterology, Gifu Municipal Hospital, Gifu, Japan (Ringgold ID: RIN38226)

  • Nobuhiko Hayashi

    12   Third Department of Internal Medicine, University of Toyama, Toyama, Japan (Ringgold ID: RIN34823)

  • Tsuyoshi Mukai

    13   Gastroenterological Endoscopy, Kanazawa Medical University, Ishikawa, Japan (Ringgold ID: RIN12857)

  • Hiroyuki Isayama 

    10   Gastroenterology, Graduate School of Medicine, Juntendo University, Tokyo, Japan (Ringgold ID: RIN12847)

  • Ichiro Yasuda

    12   Third Department of Internal Medicine, University of Toyama, Toyama, Japan (Ringgold ID: RIN34823)

  • Yousuke Nakai

    3   Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan (Ringgold ID: RIN13143)
    14   Internal Medicine, Institute of Gastroenterology, Tokyo Women’s Medical University, Tokyo, Japan
    • on behalf of the WONDERFUL study group
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Letter to:

Morphological features and not the timing determines the outcome of endoscopic ultrasound-guided transmural drainage of walled-off necrosisEndoscopy 2025; 57(12): 1423-1423
DOI: 10.1055/a-2706-0147

10.1055/a-2706-0147

We would like to thank Dr. Ancil and colleagues for their valuable comments on our research. After reading your comments, we reviewed the computed tomography (CT) images after endoscopic ultrasound (EUS)-guided drainage in our cohort. We did not encounter any cases with an overt pneumoperitoneum or pneumoretroperitoneum, but with careful evaluation, a small amount of air was observed in 54.5% (24/44) of the partial/no encapsulation group and 20.7% (35/169) of the complete encapsulation group (P < 0.001). The presence or absence of this minute pneumoperitoneum or pneumoretroperitoneum was not associated with any clinical adverse events. These data suggested the appearance of pneumoperitoneum and pneumoretroperitoneum after EUS-guided drainage may be associated with encapsulation of walled-off necrosis (WON) as you pointed out; however, in clinical practice, the degree of encapsulation needs to be preoperatively evaluated to determine whether or not to proceed with EUS-guided drainage.

Encapsulation can be associated with liquification of WON contents, which allows better drainage outcome with EUS-guided drainage. In our study cohort, the partial/no encapsulation group tended to have more necrotic contents; when the degree of necrotic contents were categorized as <30%, 30%–60%, and >60% on the pretreatment CT scans, the proportions of patients in each category were 22.7%, 61.3%, and 15.9% in the partial/no encapsulation group, and 25.2%, 68.9%, and 5.7% in the complete encapsulation group, respectively (P = 0.08); however, the proportion of necrotic contents in WON can be measured more accurately by magnetic resonance imaging (MRI) than by CT.

In summary, encapsulation is associated with clinical outcomes of EUS-guided treatment of WON, but the appropriate imaging modality and its criteria should be further investigated and the integration of artificial intelligence may play a role in future in the standardization.



Publication History

Article published online:
27 November 2025

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