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Short answer: A semi-rigid ureteroscope is an endoscope for the urinary tract whose shaft is housed in a pliable metallic sheath, which places it between a fully rigid scope and a flexible one. In the United States FDA files it under product code FGB, “Ureteroscope And Accessories, Flexible/Rigid”, a Class 2 device under 21 CFR 876.1500.
General product information for laboratory, clinic and supply staff. This page is not medical advice and does not describe how any procedure is performed.
Definition and scope
A ureteroscope is an endoscope used to look inside the ureter. FDA’s classification record for product code FGB gives the intended use as “to perform various diagnostic and therapeutic procedures within the urinary tract.” The regulation behind it, 21 CFR 876.1500, describes endoscopes as devices “used to provide access, illumination, and allow observation” through “various rigid or flexible instruments that are inserted into body spaces,” and notes that they may include an optical system for conveying an image to the user’s eye, plus accessories that assist access or add versatility.
The urology literature sorts ureteroscopes into rigid, semi-rigid and flexible types. A semi-rigid scope is the middle category, and it is the one this page covers. For the neighbouring instrument used in the bladder, see cystoscope vs ureteroscope; for a broader primer, see what an endoscope is.
How a semi-rigid scope is built
A 2014 review in Translational Andrology and Urology (Wetherell and colleagues) states that “semi-rigid ureteroscopes are usually housed in a pliable metallic sheath,” whereas “flexible ureteroscopes do not have a rigid outer layer.” The same review says rigid ureteroscopes “use a non-flexible optical lens system” and that flexible scopes “are smaller than their rigid and semi-rigid counterparts.” Those sentences are the clearest published way to tell the three apart: the difference is the outer layer and the optics, not the brand or the length.
Types and related terms
| Term | What the sources say it means |
|---|---|
| Rigid ureteroscope | Uses a non-flexible optical lens system (Wetherell et al.) |
| Semi-rigid ureteroscope | Usually housed in a pliable metallic sheath (Wetherell et al.) |
| Flexible ureteroscope | No rigid outer layer; smaller than rigid and semi-rigid scopes (Wetherell et al.) |
| Digital ureteroscope | Transmits images from a digital sensor at the tip to a proximal point via a single wire (Wetherell et al.) |
Digital ureteroscope
“Digital” describes how the image is captured, not how stiff the shaft is. A review of digital ureteroscopes (Gridley and Knudsen, Research and Reports in Urology, PubMed 28203551) says that over roughly the preceding ten years ureteroscopy entered “the digital era” with “both semirigid and flexible options becoming available.” A digital semi-rigid scope is therefore a semi-rigid scope with a sensor-based image chain, and a digital flexible scope is the flexible equivalent.
Regulatory cross-walk for supply and quality staff
- FDA’s classification database has no separate code for semi-rigid scopes. They sit with flexible and rigid scopes under FGB, “Ureteroscope And Accessories, Flexible/Rigid” (Class 2, regulation 876.1500, review panel GU, as listed in the database).
- The record’s definition says that for reusable flexible endoscopes in this product code, validated reprocessing instructions and reprocessing validation data must be included in a 510(k) submission (82 FR 26807). The wording is about flexible reusable endoscopes; do not read it as a statement about semi-rigid scopes either way.
- The same product code also lists digital and single-use flexible systems in its 510(k) records, which is one reason the code name covers a wide range of designs.
For how reprocessing is generally approached, see endoscope reprocessing. For how the 510(k) pathway works, see FDA device classification, 510(k) and PMA. Another endoscope filed under the same regulation is covered in choledochoscope, and ureteroscopy background appears in JJ stent.
Common misunderstandings
- “Semi-rigid means partly flexible at the tip.” The source describes the sheath as pliable metal, and contrasts it with flexible scopes that have no rigid outer layer. Tip deflection is not what defines the category in the published descriptions cited on this page.
- “Digital means flexible.” Digital refers to the sensor; digital options exist for both semi-rigid and flexible scopes.
- “FGB covers only flexible scopes.” The code name is “Flexible/Rigid,” and semi-rigid scopes have no code of their own.
FAQ
What is a semi-rigid ureteroscope?
An endoscope for the urinary tract whose shaft is usually housed in a pliable metallic sheath, distinct from rigid scopes with a non-flexible lens system and flexible scopes with no rigid outer layer.
What is a digital ureteroscope?
A ureteroscope that sends images from a digital sensor at the tip to a proximal point via a single wire. Digital options are described for both semi-rigid and flexible designs.
How does FDA classify ureteroscopes?
Under product code FGB, “Ureteroscope And Accessories, Flexible/Rigid”: Class 2, 21 CFR 876.1500, per the openFDA classification database, checked 2026-10-31.
Sources
- openFDA device classification, product code FGB, api.fda.gov, checked 2026-10-31.
- 21 CFR 876.1500, Endoscope and accessories, Cornell LII, checked 2026-10-31.
- Wetherell DR et al., “Advances in ureteroscopy,” Transl Androl Urol 2014;3(3):321-327, PMC4708582, checked 2026-10-31.
- Gridley CM, Knudsen BE, “Digital ureteroscopes: technology update,” Res Rep Urol, PubMed 28203551, abstract checked 2026-10-31.
