Primary objective of this study is to assess the correlation between tip of the nose motion and head motion. Secondary objective is to assess the immobilization capacity and comfort of different masks in the context of SRS with the ICON system.
ID
Source
Brief title
Condition
- Nervous system neoplasms malignant and unspecified NEC
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The correlation between nose-tip motion and position with respect to motion and
position of the head of the subject. Per fraction we will have at least 18000
measurements (30 minutes x 10 Hz) based on which we can build a correlation
model. Based on the EM tracking system and the CBCT data we can calculate the
actual tumour displacement during a fraction. For different thresholds of
actual tumour motion (0.5 mm, 1 mm, 1.5 mm, and 2 mm) we will establish the
needed threshold for the HDMM system, and its accuracy in detecting the motion.
Secondary outcome
The immobilization capabilities of the different masks will be assessed as the
position and orientation deviation of the three sensors on the head in time
with respect to the first measurement using a rigid point match.
The comfort of the different masks will be assessed based on scoring of the
volunteers. For each mask they will score the comfort on a scale of 1 to 10.
Data will be evaluated in a paired manor as this is observer dependent.
Background summary
The incidence of brain metastases has increased over time as a result of the
increased use of MRI and improvements in the treatment of primary tumors and
systemic disease. When the brain metastasis are limited in size and number,
stereotactic radiosurgery (SRS) is one of the main treatment options. Currently
we are treating our patients with a linear accelerator (linac). After the tumor
delineation, a safety margin is added to the target volume to account for
patient set-up and intra-fraction motion in the actual treatment plan. An
alternative irradiation delivery machine specifically designed for brain
irradiation is the Gamma-Knife, known for its accurate and stable patient
set-up and stability for one single fraction SRS. In the past, accuracy of SRS
was guaranteed by mounting a stereotactic frame on the head of the patient. The
latest Gamma Knife, the ICON, is equipped with an on-board cone-beam computed
tomography (CBCT) imaging system. On this system, recently installed in our
hospital, fractionated SRS is possible using a less invasive thermoplastic mask
for patient set-up and immobilize the patients. During the actual SRS a
reflective marker on the tip of the nose is tracked with an optical tracking
system to detect any patient movement. If motion thresholds are exceeded, the
SRS is stopped and setup is repeated. The standard mask for SRS provided by
Elekta deviates substantially from the masks used for our linac based SRS.
In this study we would like to investigate if the stability of the tip of the
nose is representative for the stability of the head of the patient, and what
the immobilization capacity and comfort is of different types of masks.
Study objective
Primary objective of this study is to assess the correlation between tip of the
nose motion and head motion. Secondary objective is to assess the
immobilization capacity and comfort of different masks in the context of SRS
with the ICON system.
Study design
This will be a prospective study with a volunteer part and a patient study
part. The volunteer study (colleagues) will be used to compare different masks.
In the patient study we will monitor the actual head stability during SRS in
comparison to the nose stability
Study burden and risks
Patients: The risks associated with participation can be considered negligible
and the burden can be considered minimal.
Volunteers: three different masks will be made and the volunteer has to lay
still for three times thirty minutes on three different days. They may
experience some discomfort due to the mask.
Plesmanlaan 121
AMSTERDAM 1066CX
NL
Plesmanlaan 121
AMSTERDAM 1066CX
NL
Listed location countries
Age
Inclusion criteria
Patient must be planned for mask based or frame based SRS on the ICON system at our institute
Patients/Volunteers must be 18 years or older
Patients/Volunteers must sign informed consent
Exclusion criteria
A contra-indication for use of the Elektromagnetic tracking system, e.g. a pacemaker.
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL62438.031.17 |