Sphincterotome: What It Is, FDA Class and Labeling

General product and regulatory information for laboratory, clinic and supply staff. It is not medical advice and not instructions for using the device.

Short answer

A sphincterotome (also called a papillotome) is a sterile, single-use endoscope accessory: a long plastic tube with a wire running through it and a short exposed length of wire at the tip. FDA’s 510(k) records place it under 21 CFR 876.4300 (endoscopic electrosurgical unit and accessories), Class II, product code KNS. Its labeled use is cannulation of the biliary ducts and transendoscopic sphincterotomy of the papilla of Vater and/or the sphincter of Oddi.

Definition and scope

In the FDA 510(k) summary for the Zhejiang Soudon Disposable Sphincterotome (K232476, decision November 7, 2023), the device is described as “a sterile, single use device compatible with the working channel of endoscope” that “consists of a long plastic tube with a wire running the length of its interior,” with a small portion of the wire exposed at the distal end. The cutting wire works through “the thermal effect produced by high-frequency current.” The predicate device in that submission is listed as using monopolar radio frequency current.

The same summary notes that models with an injection feature can inject contrast medium into the biliary ducts. Boston Scientific’s instructions-for-use summary for its Autotome-family sphincterotomes (ENDO-270305-AC, October 2025) also states that the sphincterotome “can also be used to inject contrast medium.” Sphincterotomes therefore sit between two product groups that supply teams often track separately: endoscope accessories and electrosurgical accessories.

How the labeling describes its use

Both sources state the indication in nearly the same words: “selective cannulation of the Common Bile Ducts (CBD) and the transendoscopic sphincterotomy of the Papilla of Vater and/or the Sphincter of Oddi” (Boston Scientific), or “cannulation of the biliary ducts and the transendoscopic sphincterotomy…” (K232476). The Boston Scientific summary adds that contraindications “are those specific to endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (ES).” The device passes through the working channel of an endoscope, so it is used together with an endoscope and an electrosurgical generator rather than on its own. This page does not describe procedure technique; that belongs to the manufacturer’s instructions and clinical training.

Regulatory identity: what FDA lists

The K232476 clearance letter gives: regulation number 21 CFR 876.4300, regulation name “Endoscopic Electrosurgical Unit and Accessories,” regulatory class II, product code KNS. FDA’s product classification entry for KNS reads “Unit, electrosurgical, endoscopic (with or without accessories).” The regulation itself defines the category as “a device used to perform electrosurgical procedures through an endoscope” and classifies it as Class II (performance standards). The regulation’s list of generic types does not name the sphincterotome; the device is cleared under this regulation through 510(k)s such as K232476.

The FDA records cited on this page list product code KNS and 21 CFR 876.4300 for this device.

Related devices and terms

• Papillotome is the alternative name for the same device type.
• Needle-knife variants: Boston Scientific’s single IFU summary covers the Autotome RX, Jagtome RX, Dreamtome RX, Hydratome RX, Ultratome XL, MicroKnife XL and RX Needle Knife XL, showing that one manufacturer’s labeling spans several sphincterotome and knife designs.
• Other ERCP-related accessories have their own pages: the stone basket and the choledochoscope.
• Endoscope reprocessing concerns the reusable endoscope, not this accessory, which is labeled for single use; see endoscope reprocessing. For the specialty context, see what is gastroenterology.

Where it matters for labs, clinics and supply decisions

The two primary sources support a short checklist of what the labeling and regulatory records state. It reports what the documents say; it is not a buying recommendation.

Item on the label or summary	What the sources state	Source
Indication	Cannulation of the biliary ducts and transendoscopic sphincterotomy; some models inject contrast medium	K232476; Boston Scientific IFU summary
Sterility and reuse	Supplied sterile, single use only; “Do not reuse, reprocess or resterilize”	K232476; Boston Scientific IFU summary
Regulatory class and code	Class II; 21 CFR 876.4300; product code KNS	K232476 letter; FDA product classification
Endoscope compatibility	Must fit the endoscope’s working channel; minimum accessory channel is a listed specification	K232476 summary
Generator	Energized by high-frequency current from an electrosurgical generator; the IFU summary addresses grounding with the endoscope manufacturer	K232476; Boston Scientific IFU summary

Specifications differ by model, so they are read from each product’s own labeling. In K232476, the proposed device and its predicate (K201121) are compared in the summary as follows:

Specification	Proposed device (K232476)	Predicate (K201121)
Guide wire diameter	0.89 mm	0.63 mm and 0.89 mm
Minimum accessory channel	2.4 mm	2.8 mm
Working length	2000 mm	1800 mm

The summary rates the channel and length differences “Similar” and reports non-clinical (bench) testing; it states that no clinical study is included. These are values for two specific products, not typical values for the category. Other facts in that summary (ethylene oxide sterilization at a sterility assurance level of 10^-6, a three-year shelf life, ISO 10993-1 biocompatibility) belong to that one product and should not be assumed for another.

Common misunderstandings

• “It can be cleaned and reused like an endoscope.” Both sources label the device single use. The Boston Scientific summary states that reuse or reprocessing may compromise structural integrity and the insulation between lumens, and may create a risk of contamination.
• “Any sphincterotome fits any endoscope.” The minimum accessory channel and working length are per-model values, as the table above shows.
• “It is a standalone cutting tool.” The wire is energized by high-frequency current from an electrosurgical generator, so the generator and return electrode are part of the system the labeling describes.
• “FDA classifies it under a dedicated sphincterotome regulation.” FDA’s records place it under the general endoscopic electrosurgical regulation, 21 CFR 876.4300.

FAQ

What is a sphincterotome?

A sterile, single-use endoscope accessory with an energized cutting wire at its tip, labeled for biliary duct cannulation and transendoscopic sphincterotomy of the papilla of Vater and/or sphincter of Oddi.

Is a sphincterotome the same as a papillotome?

Yes, papillotome is the other name used for the same device type.

How does FDA classify it?

The 510(k) K232476 lists 21 CFR 876.4300, Class II, product code KNS.

Can a sphincterotome be reprocessed?

The manufacturer labeling says no: “For single use only. Do not reuse, reprocess or resterilize.”

Sources

All sources below were checked on 2026-10-31.

• FDA 510(k) clearance letter and summary K232476, Disposable Sphincterotome, decision November 7, 2023: https://www.accessdata.fda.gov/cdrh_docs/pdf23/K232476.pdf
• 21 CFR 876.4300, Endoscopic electrosurgical unit and accessories: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-876/subpart-E/section-876.4300
• FDA product classification database, product code KNS: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpcd/classification.cfm?id=KNS
• Boston Scientific, Autotome family brief summary of instructions for use, ENDO-270305-AC, October 2025: https://www.bostonscientific.com/content/dam/bostonscientific/endo/portfolio-group/Autotome/dfu_autotomesuite.pdf