RU2690103C1 - Tracker fixation connector for neuronavigation - Google Patents

Abstract

FIELD: medicine.SUBSTANCE: invention relates to medical equipment and can be used in various fields of surgery and endoscopy and neuronavigation. Connector for fixing trackers for neuronavigation contains a tracker retainer, a fixing clamp, a hook of the connector, a fixing screw attached to the sphere. Sphere is additionally installed with possibility of movement and fixation on sphere of hemisphere with cut off base by 2/5 of radius. First tracker is fixed in the center of the hemisphere, the second tracker is fixed on its side surface so that it forms angle of 90 degrees with the first tracker.EFFECT: use of invention provides maximum possible viewing angles and position of tracker in emitter work field.1 cl, 2 dwg

Description

The invention relates to the field of medical technology and can be used in various fields of surgery and endoscopy and neuronavigation.

Stryker has a NavLock adapter for using non-standard tools (https://nse.stryker.com/products/stryker-nav3i-platform/). This tool was developed for use in spinal surgery, but without taking into account its position on the instrument, which is located directly in the surgical field.

The disadvantage of this adapter is to work only in one plane. Even with a slight change in the position of the tracker in this plane, it does not fall into the viewing angle of the infrared sensors of the navigation station. When the adapter is fixed on the neurosurgical instrumentation, its position will be perpendicular to the surgical field and it will fall out of the receiving area of the infrared emitter and receiver. Also, movement in a single plane is possible only when the adapter is not fixed on a registered tool; otherwise, the teeth of the turning mechanism cannot be shifted relative to each other.

The basis of the invention is to create a connector fixing the tracker for neuronavigation, which compensates for all these shortcomings and will provide an opportunity to increase the viewing angle of the trackers. The main technical task was to ensure the maximum possible viewing angles and position of the tracker in the field of operation of the radiator.

The solution of the technical problem is ensured by the fact that in the connector there are fixations for trackers for neuronavigation, containing a tracker lock, a fixing clamp, a connector hook, a fixing nut, a pin bonded to the sphere. Hemisphere is additionally installed on the sphere with the possibility of its movement and fixation, with the base cut off by 2/5 radius, with the first tracker fixed in the center of the hemisphere, the second tracker fixed on its side surface so that it forms an angle of 90 degrees with the first tracker.

The proposed device was developed based on the experience of using it in neurosurgical practice during spinal surgery. It was not possible to use a standard adapter on the tools of various models and manufacturers.

In the tracker, the camera receiving and reflecting infrared radiation are located on one of the small sites, changing their position is impossible. To work with it requires a large range of rotation of the tool and the tracker itself. Since this is impossible in a standard hook, the optimal shape was taken as the basis - a sphere.

The connector for fixing trackers for neuronavigation basically has a sphere with a hemisphere fixed on it with a cut-off base (2/5 of the radius), which interact with each other according to the principle of operation of the bearing. The full block of their interaction is carried out by a fixing screw located in the internal thread of the hemisphere. The sphere is fixed on the central pin. This design is attached to the toolbox with a fixing clamp, and closed with a nut from the center pin.

The tracker tabs are located on the hemisphere as follows: one of them is installed exactly in the center of the hemisphere, the second on its side surface forming an angle of 90 degrees with the first lock in perspective.

The presence of the hemisphere, on which the tracker fixers are installed with the possibility of their movement and fixation in all planes, makes it possible to carry out operations with a different position of the tool in the wound. Depending on the complexity and volume of the operation, due to the lack of tools, a large flow of surgical interventions, and simply out of habit or convenience, neurosurgeons are forced to use different tools (diameter, company, length, etc.). Considering all the above reasons, the proposed device fits optimally into neurosurgical practice as an indispensable device when working with frameless neuronavigation.

The invention is illustrated in FIG. 1, which shows the connector for fixing trackers for neuronavigation. FIG. 2 shows the fixation connector trackers for neuronavigation, attached to the working tool.

Connector fixing trackers for neuronavigation contains:

1. Tracker lock

2. Fixing clamp

3. Connector Hook

4. Set screw

5. Sphere

6. Central threaded pin

7. Locking nut

8. Hemisphere with tracker catches

Connector fixing trackers for neuronavigation is used as follows.

Knowing the tools used in advance, they are determined with the hook dimension (2 variants are offered: 20 mm. And 30 mm.) Of the connector. On the center pin 6 there is a locking clamp 2, with the help of the hook 3 and clamp 6 the device is fixed to the tool used. The locking nut 7 stops the return stroke of the clamp 2 along the thread of the central pin 6. On the hemisphere 8, the tracker (not shown) is fixed with the help of the latch 1 and its position within the surgical field is determined. The locking screw 4 fixes this position on the sphere 5. The movement of the locking nut 7 and the internal screw is carried out using a screwdriver-wrench (not shown). If necessary intraoperatively, it is possible to change the position of the hemisphere 8 depending on the stage of the operation, thereby changing the position of the tracker.

Usage example

Upon admission of the victim with severe combined injury, in the presence of spinal injuries requiring urgent neurosurgical treatment, a computed tomography (CT) scan of the injured section is performed according to the protocol (an MRI examination is also possible, a series of X-rays). After the study is completed, the necessary information (3D reconstruction and mapped sections of the damaged spine) is loaded onto the disk.

The next step is to import the CT data, which is a scanned image of the patient, this is the first step in the planning procedure. Next, select the images needed for the operation. Then we form the image we need, remove unnecessary sections of soft tissue, highlighting only the bone of the spine and its ligamentous apparatus.

Next on the selected images we make the installation planning of the fixing system screws. Here it is necessary to choose the diameter, length of the screws and the place of their position and fixation.

After accessing and skeletonizing the vertebrae of the damaged department, we begin work on navigation. We install a spinal tracker that is rigidly fixed to the spinous process at the base of the wound using a special device. Here we need with the help of a registered pointer to put additional landmarks on the vertebrae.

The accuracy of the screws and the amount of surgical intervention will largely depend on the rigidity of fixing the instruments, the correctly chosen additional points and landmarks, and the location of the tracker, which must be rigidly fixed to the instrument used in the operation.

In order to fully use the tools within the operating field, as well as in the contact area of the camera and the infrared radiation sensors of the navigation rack, you need a tool that will perform all these actions.

The developed tracker fixation connector will be fixed to the toolkit chosen by us, register and perform all necessary actions within the operating field. Since the scope of this connector implies the movement of the tracker and its fixation in all planes and angles of inclination (which is impossible to do with the connector proposed by Stryker), its use will be optimal.

After attaching the spinal tracker to the spinous process and its detection, we begin to register and validate instruments in the field of operation of the infrared emitter. After the vector calibration, we apply additional bone landmarks using a pointer.

We proceed to the installation of screws stabilizing design. With an awl, we perform a puncture of the cortical layer of the root of a vertebral arch at the place of screw installation. Then, using a pedicle probe, on which the connector developed by us with a tracker fixed to it is installed, determining the angle, direction and depth using the navigation stand, we pierce the cancellous arc and the vertebral body to the required depth. The next step is to cut the thread with a modular tap using a connector. The final step is to install the screw with a polyaxial screwdriver (on which the tracker fixation connector is also fixed).

At each stage of the operation, work with a surgical instrument is carried out using the tracker fixation connector and linking it to the coordinate system and vector marking of the navigation bar.

The invention is illustrated in FIG. 2, which shows a connector for fixing trackers for neuronavigation, attached to a working tool (in this figure a guide tap) to which the tracker is fixed. The tool is brought to the place of the subsequent installation of the screw of the fixing structure.

Claims (1)

Connector for fixing trackers for neuronavigation, containing tracker lock, clamp fixing, connector hook, fixing screw attached to the sphere, while the sphere is additionally mounted so that the hemisphere with the base cut off is 2/5 of the radius, the first tracker it is fixed in the center of the hemisphere, the second tracker is fixed on its side surface in such a way that it forms an angle of 90 degrees with the first tracker.

Images