Announcement of Publication on a Disposable Ultra-fine Endoscope for Peritoneal Dialysis

We are pleased to announce that the results of a multi-center clinical study utilizing a disposable ultra-fine endoscope for peritoneal dialysis—a device currently under development by our company—have been published in the international scientific journal ‘Scientific Reports’.

Peritoneal dialysis (PD) is a vital form of renal replacement therapy that can be performed at home, allowing patients to maintain their independence and quality of life (QOL). However, long-term PD treatment can lead to structural and functional changes in the peritoneum, potentially resulting in a serious complication known as encapsulating peritoneal sclerosis (EPS)¹⁾. Currently, methods such as the Peritoneal Equilibration Test (PET)²⁾, measurement of biomarkers in effluent³⁾, and CT scans are used to assess the condition of the peritoneum; however, these tests do not allow for direct observation of the peritoneal surface. While direct observation is possible using conventional laparoscopy⁴⁾, the procedure requires surgery and anesthesia, making it difficult to perform repeatedly on stable PD patients. Consequently, there has been a need for a practical, minimally invasive method to directly evaluate peritoneal morphology over time.

In collaboration with institutions such as St. Luke’s International Hospital, Juntendo University, and Jikei University School of Medicine, we have developed a disposable ultra-fine endoscope capable of visualizing the abdominal cavity through the indwelling PD catheter. This endoscope allows for direct observation of the peritoneal surface and the interior of the PD catheter without the need for anesthesia, while the PD fluid remains in the abdominal cavity. The outer diameter of the endoscope’s insertion section used in this study is 1.3 mm.

In this multi-center clinical study, we used the endoscope to observe the peritoneum and the interior of the PD catheter in 60 patients undergoing peritoneal dialysis. Furthermore, we conducted follow-up observations on 49 of these patients approximately 12 months later to evaluate changes in peritoneal findings over time. As a result, all observations were safely performed on an outpatient basis without anesthesia, and no procedure-related adverse events were observed. Fibrin adhesion was found inside the PD catheter in 87% of patients, while fibrin deposition, neomembrane formation, and microvascular abnormalities were observed on the peritoneal surface.

A notable aspect of this study is the frequent observation of minute fibrin deposits on the peritoneal surface—findings that were difficult to capture with conventional laparoscopy. Unlike conventional laparoscopy, which requires draining the dialysis fluid for observation, this endoscopic method allows for visualization while the fluid remains in the peritoneal cavity; this enables the observation of fine fibrin fibers, their movement, and their spatial relationship with surrounding tissues in an environment closer to physiological conditions. Furthermore, fibrin deposition was observed in conjunction with neomembrane formation and microvascular abnormalities, suggesting that these findings could provide crucial morphological information for understanding the pathophysiology of peritoneal injury.

However, no significant association was found between these peritoneal findings and the duration of peritoneal dialysis. Follow-up observations conducted approximately 12 months later revealed both the appearance of new findings and the disappearance of previously observed ones. These results indicate that the morphological state of the peritoneum can change over time and that the duration of peritoneal dialysis alone may not fully capture an individual patient’s peritoneal condition.

The significance of this endoscopic technique lies in its ability to provide direct, repeated, and patient-specific observation of peritoneal surface morphology—details that were previously difficult to fully assess. If future research clarifies the relationship between endoscopic findings and changes in peritoneal function or clinical outcomes, this method could provide objective data based on a patient’s actual peritoneal condition—rather than just the duration of dialysis—to inform decisions regarding the continuation of peritoneal dialysis or the transition to hemodialysis. Ultimately, this technique holds promise as a new tool for observation and assessment that could shift peritoneal dialysis care from decisions based on treatment duration to personalized treatment decisions grounded in the specific condition of the peritoneum. This ultra-fine endoscopic system consists of an endoscopic component for visualizing the abdominal cavity and a guide catheter component designed to enhance operability. The endoscopic component has already received regulatory approval. Details are as follows:

・ Approval Number: 30400BZX00294000
・ Generic Name: Flexible Laparoscope
・ Brand Name: Trans-catheter Laparoscope PD VIEW
・ Classification Code: Instrument 25

Manufacturing of the guide catheter is also complete, and preparations are currently underway to submit an application for regulatory approval during the 2026 fiscal year. The guide catheter was developed to enable a wider and more stable field of view around the tip of the PD catheter; once approved, it is expected to further improve the operability and clinical utility of peritoneal observation using this ultra-fine endoscope.

¹⁾ Encapsulating Peritoneal Sclerosis (EPS)
A serious complication that can arise from long-term PD. It is a condition in which the peritoneum hardens and thickens, causing intestinal adhesions that lead to complications such as intestinal obstruction (ileus). Symptoms include abdominal pain, vomiting, constipation, and ascites; the condition can be life-threatening as it progresses. Early assessment of the patient’s condition and appropriate management—including the discontinuation of peritoneal dialysis or a transition to hemodialysis—are crucial.

²⁾ Peritoneal Equilibration Test (PET)
A test used to evaluate the peritoneal function of PD patients, specifically the transport characteristics of solutes and water.

³⁾ Measurement of Biomarkers in Effluent
This is conducted for research and clinical purposes to assess the condition of the peritoneum and the presence of inflammation. Representative markers include CA125, which reflects the state of peritoneal mesothelial cells, and IL-6, which is associated with inflammation.

⁴⁾ Laparoscopy
In a standard laparoscopic procedure, small incisions (ranging from a few millimeters to about 1 cm) are made in the abdomen, and a camera (scope) is inserted into the abdominal cavity for observation. While this allows for direct visualization of the peritoneum, it typically involves surgical intervention and anesthesia; therefore, it is not suitable as a repeated examination for stable peritoneal dialysis patients.