Intra-operative Evaluation of the External Ventricular Drain Catheter Position With Structured Light for Patients (Bullseye EVD)

Intra-operative Evaluation of the External Ventricular Drain Catheter Position With Structured Light

The placement of external ventricular drainage (EVD) is a life-saving procedure used to relieve high pressures in the brain. Often performed at the bedside, a small tube (catheter) is inserted into one ventricle of the brain to drain cerebrospinal fluid and release the pressure build up. In standard practice, EVDs are placed freehand and initial catheter malpositioning occurs in up to ~60% of procedures. Currently, there are no adequate means to verify the position of the catheter before insertion which is a significant impediment to ensure accurate positioning. This non-interventional study aims to validate a novel technology, Bullseye EVD, for verifying the position of the EVD catheter during these emergency procedures.

Study Overview

• Status: Recruiting
• Conditions: Intracranial Pressure Increase

Detailed Description

External ventricular drainage (EVD) is a life-saving procedure used to release cerebrospinal fluid and relieve elevated intracranial pressure due to acute hydrocephalus, often secondary to subarachnoid hemorrhage, spontaneous intracerebral hemorrhage or traumatic brain injury (TBI). To drain cerebrospinal fluid (CSF) from the ventricular system and relieve pressure on the brain, a catheter is inserted into the ipsilateral frontal horn of the lateral ventricle (IFHLV) close to the Foramen of Monro (FoM). Twist-drill trephination is utilized to create a frontal burr hole at Kocher's point, approximately 11.5cm superior to the nasion and 2-3cm lateral of the midline. The dura is perforated, and the catheter is inserted with a rigid stylus. The current standard of care is a freehand technique which is often performed by neurosurgeons at the bedside in the ICU. It relies on surface anatomical landmarks to guide the catheter trajectory towards the FoM perpendicular to the calvarial slope at Kocher's point. However, the freehand technique is challenging to accurately perform, often requiring multiple passes of the catheter through the brain, with trajectory deviation most critical to malpositioning. Up to 24% of malpositioned EVDs require revision or reinsertion which can significantly increase catheter-associated infection. Up to 45.5% of EVD procedures require multiple passes for successful catheter insertion (6). This can lead to hemorrhage along the catheter tract (up to 34%, catheter dysfunction (up to 38%, and catheter-associated infection (up to 36% which increase EVD-associated health care costs (up to 20%). EVD malpositioning outside of the IFHLV (up to 60%) has been associated with other rare but significant complications including coma and diabetes insipidus. Large deviations in catheter placement have resulted in catheter insertion into significant brain regions (thalamus, hypothalamus, basal ganglion, internal capsule. Angular error within the coronal plane is the primary determinant of successful catheter insertion.

Bullseye is a novel intra-procedural system the investigators initially developed for glenoid guidepin placement. Bullseye EVD uses a verification workflow (guess and check) to identify EVD catheter position and trajectory with reference to the diagnostic CT image prior to catheter insertion using structured-light imaging. Structured-light scanning currently has several medical applications due to its speed, accuracy, and robust 3D surface reconstruction, and has been investigated in planning bedside subdural evacuation port system placement. In vitro performance of Bullseye EVD was demonstrated through testing on 3 cadaveric specimens to localize EVD placement on both sides of each of the heads (N=6 trials in total). The success of this in vitro work motivated further development of the technology including clinical evaluation for EVD.

Reducing EVD malpositioning and associated complications is a priority for neurosurgeons, however costly and cumbersome navigation solutions have had limited uptake in this urgent procedure that is often conducted at the bedside. Bullseye EVD represents a portable, safe, low-cost technology that can identify catheter positioning on existing preprocedural CT imaging. The proposed work, including integration into the existing clinical workflow, evaluation of in vivo accuracy and automation to enable rapid feedback during EVD placement, is critical to translating this technology from the bench to the bedside.

• Study Type: Observational
• Enrollment (Estimated): 15

Contacts and Locations

• Study Contact: Name: Cari Whyne, PhD, FIOR; Phone Number: 65056 416-480-6100; Email: cari.whyne@sunnybrook.ca
• Study Contact Backup: Name: Katrine Milner; Phone Number: 416-480-4285; Email: Orthores@Sunnybrook.ca

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M4N 3M5
      • Recruiting
      • Sunnybrook Health Sciences Centre
      • Contact: Cari Whyne, PhD; Phone Number: 5056 4164806100; Email: cwhyne@sri.utoronto.ca
      • Contact: Layla Pires; Email: laylabtu@gmail.com
      • Principal Investigator: Cari Whyne, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

A total of 15 patients will be enrolled in this study at Sunnybrook Health Sciences Centre's ICU. The PI, study team members who are part of the circle of care, and study personnel will identify potential study participants. The Research Coordinator or assistant will approach for consent.

Given that the clinical procedure involved- the EVD- is an urgent procedure with short timelines, s deferred consent model may also be used in this study as it satisfies the conditions for deferred consent as set out in the Tri-Council Policy Statement: Ethical Conduct for Research Involving Humans - TCPS 2 (2022) Article 3.7A,.

Description

Inclusion Criteria:

1. ≥18 years of age
2. Scheduled to undergo placement of an EVD
3. Located in B5 ICU or CRCU
4. Existing pre-procedural head CT imaging

Exclusion Criteria:

1. Set up time poses a safety risk (Clinical discretion)

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Accuracy of the structured light computer vision system	The primary study outcome will be the accuracy of the structured light computer vision system. This will be quantified as the difference between predicted and actual position of the EVD catheter measured as a combined analysis of version error (degrees), inclination error (degrees), and offset error (mm).	Data analysis to start immediately post procedure.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Procedural time for Fiducial placement and optical imaging	The number of minutes required for these additional tasks	Time measured during procedure
Workflow integration	Analysis of the current workflow and changes required to enable the use of Bullseye EVD	Immediately after procedure
User feedback	User feedback to evaluate acceptability and utility of the technology by the surgeons and procedural team, and to identify potential barriers and opportunities to improve safe and accurate EVD placement. This will be conducted within a user centred design framework	Immediately after procedure

Collaborators and Investigators

• Sponsor: Sunnybrook Health Sciences Centre
• Investigators: Principal Investigator: Cari Whyne, PHD, FIOR, Sunnybrook Health Sciences Centre

Study record dates

Study Major Dates

• Study Start (Actual): July 7, 2023
• Primary Completion (Estimated): March 1, 2025
• Study Completion (Estimated): November 1, 2025

Study Registration Dates

• First Submitted: May 31, 2023
• First Submitted That Met QC Criteria: June 26, 2023
• First Posted (Actual): July 6, 2023

Study Record Updates

• Last Update Posted (Actual): May 9, 2024
• Last Update Submitted That Met QC Criteria: May 8, 2024
• Last Verified: May 1, 2024

More Information

Terms related to this study

• Keywords: Intracranial Pressure; External Ventricular Drain; EVD malpositioning
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Intracranial Hypertension
• Other Study ID Numbers: Bullseye EVD

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No