510(k) · Cleared

Cleared

Knoll/Midus (Male Impotence Diagnostic Ultrasonic System)

K971790510(k) TraditionalCleared Dec 17, 1997217-day reviewClass II21 CFR 892.1550

Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly, last Nov 3, 2026

Urometrics, Inc. · IYN System, Imaging, Pulsed Doppler, Ultrasonic

Cleared on Dec 17, 1997 as substantially equivalent to K946349 (Specs USA, Inc., 1996) after a 217-day review. Its family tree reaches back 2 generations to 1986.

Decided: Dec 17, 1997
Review: 217 days
Class: Class II
Product code: IYN
Recalls: None
Predicates: 1

Its longest line of descent runs back 2 generations to K860435 (1986). No later device cites it as a predicate yet.

By dateBy generation

Root · 2 generations backK860435 Model 500A Vascular Spectrum Analyzer W/CW DopplerMultigon Industries, Inc. · 1986
1 generation backK946349 StenodocSpecs USA, Inc. · 1996
This deviceK971790 Knoll/Midus (Male Impotence Diagnostic Ultrasonic System)Urometrics, Inc. · 1997

View FIG. 1 as a table

Line of descent and top descendants

Generation	Number	Device	Applicant	Decided	Recalls
−2	K860435	Model 500A Vascular Spectrum Analyzer W/CW Doppler	Multigon Industries, Inc.	1986	—
−1	K946349	Stenodoc	Specs USA, Inc.	1996	—
0 (this device)	K971790	Knoll/Midus (Male Impotence Diagnostic Ultrasonic System)	Urometrics, Inc.	1997	—

FIG. 1 — Lineage of K971790, 1986–1997Source: FDA 510(k) summaries, read by 510(k) Report · How lineage is built

Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.

Planning a device in IYN? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.

Top candidate predicates for a new IYN device

#1 K240850 EPIQ Series Diagnostic Ultrasound Systems…score 32.1 · 24 generations · no Class I recall
#2 Held for the reportin the report
#3 Held for the reportin the report

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What was it cleared against? (1)

Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.

Type	Number	Device	Applicant	Decided	Recalls
*	K946349	Stenodoc Summary page 1 …ion), 21 CFR 8970.2100 Class I1 The Knoll/MIDUS is substantially equivalent to the SPECS USA, Inc. Stenodoc/EPC bi-directional vascular Doppler with spectral analysis (K946349). The UroMetrics Knoll/MIDUS System is an office based Doppler ultrasound system designed to measure blood velocity in the penil…	Specs USA, Inc.	1996	—

What descends from it?

No later submission names this one as a predicate yet.

Has anything in its family been recalled? (0 Class I)

No FDA recall names this device.

No ancestor or descendant has a Class I recall.

What does this lineage say?

The line of descent spans 11 years and passes through 3 companies; a new generation was cleared every 10.1 years on median.
None of the 2 ancestors has a recall.

How does its category compare?

All IYN devices

IYN System, Imaging, Pulsed Doppler, Ultrasonic: FDA decisions, review times, recalls and adverse event reports over 20 years.

FDA decisions per year · IYN

57in 2025

2007high 64 (2017) · low 13 (2007)2026

2026 to Oct 25, outlined.

Median 510(k) review, days · IYN

124in 2025

2007high 124 (2025) · low 18 (2008)2026

Receipt to decision; years with fewer than 3 clearances left blank.

Recalls per year · IYN

10in 2025

2007high 16 (2007) · low 0 (2017)2026

Class I (1 since 2007) Class II/III not classified

Adverse event reports per year · IYN

610in 2025

2007high 610 (2025) · low 2 (2008)2025

MAUDE reports naming product code IYN, not matched to any one device; reports are not rates.

View these four charts as a table

Year	Decisions	Median 510(k) review, days	Recalls (Class I)	MAUDE reports
2007	13	26	16	3
2008	25	18	12	2
2009	18	29	8	9
2010	29	67	10	17
2011	39	46	8	18
2012	43	37	3	20
2013	51	60	8	18
2014	56	39	2	48
2015	54	55	3	116
2016	60	56	2	145
2017	64	83	0	146
2018	59	85	7	85
2019	47	79	0	59
2020	57	72	4	67
2021	46	105	8	213
2022	53	105	10	186
2023	44	115	4	229
2024	50	119	1	266
2025	57	124	10	610
2026	44	107	2 (1)	—

What is it indicated for?

Measurement of penile cavernosal artery velocities. Not intended for fetal use.

Indications for use read by OCR from a scanned FDA summary, so letters may be misread. Check the PDF before quoting it.

https://510kreport.com/device/K971790 · printed Nov 5, 2026

Cite this page

510(k) Report. “K971790: Knoll/Midus (Male Impotence Diagnostic Ultrasonic System).” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 5, 2026. https://510kreport.com/device/K971790

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Record history

FDA decision record loaded May 2, 2026
Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
Lineage and recalls computed Nov 3, 2026
Page last updated Nov 3, 2026