Electromagnetic Stylet Post Market Clinical Followup Study

Placement of ventricular catheter is a well-established surgical procedure.
Intracranial catheters are mostly supplied with a
removable stiffening member, called a stylet. Stylets provide rigidity during
insertion and can be removed so that the catheter is
flexible post removal. However, these catheters do not have a means of
navigation and are commonly placed with the freehand
pass technique, which is associated with a high misplacement rate. The
development of image-guided navigation systems have
shown to substantially lower the rate of misplacement compared with the
freehand pass technique. A successfully performed
ventricular catheter placement (high tracking accuracy allows successful
catheter placement) strongly points toward the absence
of adverse events in the period after the procedure. The recently developed
Brainlab EM Stylet is being used in clinical routine,
but needs verification of accuracy and safety in a post-market clinical
followup study. (PCMF)

The aim of this PMCF study is to confirm the clinical safety and performance
aspects of intracranial catheter placements for
the medical indications, hydrocephalus of any origin or ICP elevation. The
study design requires determination of catheter
placement accuracy. As part of the treatment of hydrocephalus with
intraventricular catheters, additional imaging for verification
of the accurate placement of those catheters is a standard procedure for many
adult and pediatric patients. This can either be
done via MRI or ultrasound (the latter in the case of children younger than 12
months of age).

The study objectives are
1. Ventricular catheter location as assessed by intraoperative or postoperative
imaging (CT or MR or ultrasound in children
younger than 12 months of age) performed within 72h post-intervention.
Catheter placement accuracy will be assessed based on the following grading
system adapted from Hayhurst et al. (Hayhurst et
al., 2010):
o Grade 1: catheter tip (perforated part) free floating in cerebrospinal fluid
equidistant from ventricular walls, away from choroid
and a straight trajectory from the burr hole.
o Grade 2: lateral catheter openings touching a ventricle wall or choroid
o Grade 3: catheter tip perforated part partially or completely within brain
parenchyma or failure to cannulate ventricle completely
2. Frequency and severity of adverse events and incidents are recorded as
secondary outcome measures (secondary
endpoints) within the study period and will be collected by specific
questioning and, as appropriate, by examination. Respective
information shall be recorded by the Investigator in the Case Report
Form-Adverse Events (CRF-AE). The completed CRF-AE
shall be forwarded to the Sponsor within four weeks. SAEs, SADEs and device
deficiencies that could have led to a SADE shall
be reported to the Sponsor without unjustified delay. Assessment and processing
of the adverse events is performed by the
Sponsor.

This study design is considered appropriate to reach the study objectives.
The present PMCF study is a single center prospective non-randomized
observational non-controlled single-arm trial to investigate whether
using the EM Cranial navigation system together with the EM stylet is as good
as we think from prior clinical and pre-clinical studies.
Workflow:
• For a catheter placement, the Brainlab EM navigation system and Brainlab EM
Stylet shall be used.
• The healthcare professionals will be responsible for the procedure(s) that
the subjects undergo during surgery. This study
protocol does not contain a detailed description of the intervention that the
subjects undergo during this investigation.
• An intraoperative scan or post-OP scan (MR or ultrasound for children younger
than 12 months of age) of the catheter
location shall be performed. The post-OP scan shall take place within 72 hours
post intervention.
• The anonymised mage data sets shall be uploaded to a secure platform
(Quentry) within four weeks.
• All data shall be reviewed (e.g., by two blinded healthcare professionals
grading the catheter tip placement according to the
protocol described in Hayhurst et al.).
• One CRF must be filled in for each enrolled patient who finishes the study:

o The CRF shall be completed within four weeks of performing the intraoperative
or postoperative imaging.
o If applicable, the CRF-AE shall be submitted to the Sponsor within four weeks
to record adverse events and incidents that occur during the procedure and in
the period between device application and the post-operative scan, which must
be performed
within 72 hours post-intervention. SAEs, SADEs and device deficiencies that
could have led to a SADE event shall be reported
to the Sponsor without unjustified delay. For detailed information on adverse
events and handling, please refer to chapter 15 of
this document.

The use of the device is according to clinical routine, as it is currently
performed in our center. A subset of patients already
receives postoperative imaging of the brain using MRI or ultrasound within 72
hours. We ask these patients for permission
to use their data for analysis. The rest of the patients, that receive surgery
using the EM-stylet but do not receive postoperative
imaging within 72 hours we ask for permission to perform MRI or ultrasound
imaging to assess catheter location. The
burden and risk that is associated with participation is low. The data we
collect on the accuracy and safety of the device can assist in the development
of improvements to the device.