TruDi Navigation System suits against Acclarent: Fernihough v. Acclarent, Inc., 4:25-cv-00525 (N.D. Tex.), and Erin Ralph's suit (Texas state court)

Summary

Two patients allege that Acclarent's TruDi Navigation System, a sinus-surgery navigation device to which artificial-intelligence features were added, misled their surgeon, Dr. Marc Dean, and caused carotid artery injuries and strokes. Donna Fernihough sued Acclarent, its parent Integra LifeSciences and two component suppliers in Tarrant County on May 15, 2025, over a May 19, 2023, balloon sinuplasty. The defendants removed the case to the Northern District of Texas the next day. She alleges that the AI modification was rushed to market without proper testing and made the navigation inconsistent and inaccurate. The supplier defendants have since been dismissed, and the case is in discovery as of October 2026. Erin Ralph makes similar allegations about a 2022 procedure. In 2024 the Fort Worth Court of Appeals granted Acclarent mandamus relief from a presuit deposition and production order that Ralph had obtained in Tarrant County. Acclarent and Integra deny any causal link between the device, its AI and the injuries. All claims are unproven allegations.

Key dates

1. May 15, 2025Filed
2. October 16, 2026Checked against sources
3. October 21, 2026Checked against sources

Developments are added when the record is reviewed. Next review: January 15, 2027.

Evidence

Each passage is quoted from its source. The quoted passages are re-checked against the live pages every month.

1. The plaintiff in one of the cases, Erin Ralph, accused the company of having the device mislead surgeon Marc Dean during a 2022 procedure, causing him to injure a carotid artery, leading to a blood clot and eventually a stroke.

   Supports: Ralph's allegations

   there is no credible evidence to show any causal connection between the TruDi Navigation System, AI technology, and any alleged injuries.

   Supports: Integra's denial

   AI surgery tool injuring patients, lawsuits allege Futurism (reporting on a February 2026 Reuters investigation) Reporting or analysis

2. ORDER GRANTING 144 MOTION TO STRIKE AND DENYING AS MOOT 142 MOTION FOR LEAVE TO DESIGNATE: As a result, Plaintiff's Motion to Strike is GRANTED, and Defendants' Motion for Leave is DENIED as moot. (Ordered by Senior Judge Terry R Means on 10/9/2026 )

   Supports: Case active in October 2026; supplier defendants terminated in 2025

   Fernihough v. Acclarent, Inc. et al (4:25-cv-00525), Texas Northern District Court PacerMonitor (PACER docket data) Tracker or database

3. This case was filed in the State Court as Cause Number 067-364611-25 on May 15, 2025

   Supports: State filing date; removal (Dkt. 1 filed 05/16/25)

   Notice of Removal (Dkt. 1), Fernihough v. Acclarent, Inc., No. 4:25-cv-00525 U.S. District Court, N.D. Tex. (RECAP copy via CourtListener) Primary source

4. ACCLARENT/INTEGRA knew or should have known that the purported artificial intelligence caused or exacerbated the tendency of the integrated navigation system product to be inconsistent, inaccurate, and unreliable

   Supports: AI allegation

   On May 19, 2023, DONNA CAROL FERNIHOUGH underwent a balloon sinuplasty procedure with navigation using the TruDi Navigation System and its navigated devices by Dr. Marc Dean.

   Supports: Procedure date and surgeon

   Plaintiff's Original Petition (Dkt. 1-1) U.S. District Court, N.D. Tex. (RECAP copy via CourtListener) Primary source

5. 06/07/2024 Memorandum opinion issued Motion or Writ Granted

   Supports: Mandamus granted to Acclarent; Erin Ralph is the real party in interest; Tarrant County cause 067-344578-23

   In re Acclarent, Inc., No. 02-24-00228-CV Texas Second Court of Appeals (Texas Judicial Branch case search) Primary source

6. Erin Ralph sought a presuit deposition under Texas Rule of Civil Procedure 202 to investigate a potential product-liability claim related to injuries she sustained during sinus surgery.

   Supports: Nature of the 2024 mandamus proceeding

   Mandamus Relief Granted for Presuit Deposition and Production Order: eDiscovery Case Law eDiscovery Today (Doug Austin, July 9, 2024) Reporting or analysis