Development of a Dedicated X-Ray Fluoroscopic Apparatus for Therapeutic Pancreatobiliary Endoscopy: A Review

Abstract

In recent years, pancreaticobiliary endoscopy (PBE) has evolved to include a wide range of endoscopic procedures used to treat various diseases. Several interventional endoscopic ultrasonography procedures have been developed for conditions that cannot be treated with conventional endoscopic methods. As PBE continues to advance, it is crucial to improve fluoroscopic systems to enhance image quality, ensure patient safety, reduce radiation exposure, and ensure the operation of video-recording systems. The difficult procedures require the precise imaging of thin pancreatic/biliary branch devices, including guidewires, catheters, and stents. It is crucial to reduce noise caused by patient breathing and movement, while retaining the necessary movement in the image on the screen. A stable table is effective for ensuring the safety of patients during the procedure. A reduction in radiation exposure is important, and the flame rate conversion technique is effective. Ensuring high-quality recording is useful for the video presentation of PBE procedures. In collaboration with Fujifilm (Tokyo, Japan), we researched and developed various functions in fluoroscopic systems for PBE. In this review, we outline the requirements for fluoroscopic procedures in PBE, the evolution of technology to date, and its prospects, while also presenting the commercial equipment currently available.

Keywords: ERCP; fluoroscopic machine; fluoroscopy; interventional EUS; pancreatobiliary endoscopy.

Figure 1

History of fluoroscopic imaging research.

Figure 2

Adaptive noise reduction (ANR). (a) Before the introduction of ANR. Numerous noises are shown in the magnified field. (b) After the introduction of ANR. Noises are reduced, and the image is clearer in the magnified field. (c) ANR combined with a recursive filter.

Figure 3

Motion tracking noise reduction (MTNR). MTNR detects global motion in consecutive fluoroscopic images with high accuracy and applies motion compensation in the direction of the arrow in the image using a recursive noise filter.

Figure 4

Local moving device tracking noise reduction (TARGET). (a) Original image. (b) Line detection. (c) Global and local motion compensation. “Local” refers to devices such as guidewires. (d) Final image. Noise is reduced, and the image is clearer.

Figure 5

Background attenuation processing. (a) Original image. (b) Line detection. (c) Background image. (d) Final image. The background is subtracted, making devices clearly visible.

Figure 6

Shielding. (a) Curtain-type protective covers provide radiation shielding in all directions. (b) Protective clothing and cover collars with a lead equivalent of 0.25 mm, providing approximately 92–93% shielding effectiveness.

Figure 7

Frame rate conversion (FRC). FRC generates interpolated frames from two consecutive fluoroscopic images, improving the quality of the fluoroscopic image by increasing the frame number without increasing the radiation amount.

Figure 8

Current operation of fluoroscopic machine: CUREVISTA (Fujifilm). The offset open design allows for a large workspace on the far side of the table, making it easy to provide support to the patient. The fluoroscopy system can also be moved horizontally and vertically (in the direction of the arrows in the image), allowing procedures to be performed without moving the patient.

Figure 9

Recording system. This system can record multiple images simultaneously. (a) Fluoroscopic image. (b) Endoscopic image. (c) Peroral cholangioscopic image.