CZ24514U1 - Device to determine position of patientÆs head and shoulders - Google Patents

Description

Device for determining the position of the patient's head and shoulders

Technical field

The invention relates to a device for determining the position of the head and shoulders of a patient, in particular for medical applications in neurology and rehabilitation in order to enable the physician to identify pathological conditions in the head and shoulders and to quantify the course of treatment during rehabilitation. It is a camera system for measuring the position of the patient's head and shoulders in three-dimensional space.

BACKGROUND OF THE INVENTION

Doctors want to determine the inclination, flexion and rotation of the head and the inclination and rotation of the head to within 2 °, as there are a number of neurological disorders that can negatively affect the natural posture of the upper half of the body. For this reason, the anatomical system of axes is defined by physicians. The determination of the anatomical axis of the head is based on the definition of anatomical points on the head, which are located on the cartilaginous projection of the ear lobe, the tragus and the lower edge of the orbit, the canthus - orbit.

The determination of the anatomical axis of the shoulders is based on the definition of the anatomical point on the shoulder, which is located on a promontory called the acromion, ie the shoulder shoulder.

The identification of head and shoulders position in medicine is realized mainly by protractors. The method is limited by the accuracy and posibility of positioning the anatomical axes in accordance with the required anatomical axes. Also, pictures taken with a single camera are used to determine head position in medicine and the position of the head and shoulders is determined by protractors. Other methods based on photographic analysis of images were not practically used in medicine. Head and Shoulder Positioning also uses commercial CCTV systems that are not primarily designed for head and shoulder positioning and are limited in use since they do not define the appropriate anatomical coordinate system of the upper half of the body or do not meet the required measurement accuracy. 2 °. Electromagnetic or gyroscopic principles have also been tested to determine the position of the head and shoulders in medicine. However, the methods require the mounting of large sensors, which negatively affects the position of the patient's head and shoulders, while the methods do not allow accurate determination of the anatomical axes of the head and shoulders.

J.D. In 1988, Young proposed a head position measurement method based on the use of three mirrors and marks placed on the head. The camera captures the image of the head and determines the angles of rotation, flexion / extension and inclination, but not in accordance with the desired anatomical head axes. Such a system also makes it impossible to measure the position of the arms and the relative position of the head and arms. In 1995, V.F. Ferrario proposed a method using a camera system based on the analysis of a 12-point image of the head. Position angles are then calculated from the 20-second TV recording. The method is expensive and it is necessary to mark / identify 12 points on the head. Also this method does not take into account the possibility of studying the position of the shoulders. In 2003, Galardi proposed a measurement method35 using the Fastrack system, which is a system based on electromagnetic position detection using transmitters and receivers, but with the method we cannot define the anatomical axes of the head and shoulders, only to measure movement.

In biomedical engineering, special systems such as Zebris or SonoSens are also used to measure the position of body parts. The Zebris system uses a special head position measurement device, but it limits the patient's forward view, which has a negative impact on neurological screening, and does not detect head position in accordance with defined anatomical axes, nor does it allow the anatomical axis of the shoulder to be studied. SonoSens is a diagnostic system for dynamic analysis of body posture and movement. The system is based on ultrasonic measurement. The disadvantage of the system is the impossibility of accurately defining anatomical points due to dimensional sensors and lower accuracy, which does not allow measurement to within 2 °. No method is used to determine the position of the head and shoulders in accordance with defined anatomical axes because of its unsuitability or inadequate measurement accuracy. Systems using electromagnetic or gyroscopic principles do not allow accurate identification of anatomical axes due to very large elements placed on the anatomical points of the head and shoulders.

- I CZ 24514 Ul

In non-medical fields, head position detection is used mainly in control and control systems. Sileye O. Ba and Jean-Marc Odobez proposed a method for determining the position of the head relative to one camera. However, the measurement error is dependent on the general appearance of the face and the method does not determine the position of the anatomical axes of the head or shoulders, therefore the method does not meet the requirements of physicians.

Simon Meers, Ward Root and Lan Piper of the University of Wollongong created a head position measurement system consisting of a single camera and special glasses with infrared LEDs attached. Three infrared LEDs are attached to special glasses. This method meets the requirements for accuracy, the disadvantage is that the glasses do not define the position of specific anatomical points of interest to the physician and at the same time it does not allow to measure the position of the shoulders in space.

Ishinobu Ebisawa also designed an arrangement of one camera and two piston-shaped light sources to measure head position in space. One annular light source is located around the camera lens and the other light source is located below the camera lens. Both pupils and nostrils are detected. Unfortunately, the system does not allow to measure the position of anatomical axes of the head and shoulders.

i5 The methods listed above represent the current state of the art for identifying head and shoulder positions in space. The disadvantage of all current systems is that the systems are not adapted to measure the position of the desired anatomical axes of the head and shoulders. Also, there are no sufficiently accurate systems to detect anatomical points defining the anatomical axes of the head and shoulders.

The essence of the technical solution

The aforementioned drawbacks are largely eliminated by the device for determining the position of the head and shoulders of the patient, in particular for medical applications in neurology and rehabilitation, according to the present invention. It consists of a stand provided with a first positionable base for a camera with a vertically oriented optical axis and its position sensor and a second positionable base for a camera with a horizontally oriented optical axis and its position sensor for profile pictures of a patient with at least six reflective hemisphere markers placed on anatomical points head and shoulders. An infrared radiator is connected to the rack and a platform with marks for placing the patient's feet is attached to the bottom of the rack.

The first positionable camera base and the second positionable camera base are preferably sliding and tilting about two axes. The position sensors are preferably accurately and firmly attached to the respective cameras. The cameras with position sensors are preferably connected to a computing device.

A platform with patient foot markings can be attached to the stand and the center of the platform is located below the camera with a vertically oriented optical axis.

The camera system of measuring the position of the head and shoulders in the three-dimensional space consists of two cameras enabling the detection of markers, which are placed in the form of adhesive reflective or contrast marks on the patient's head and shoulders. The camera system is complemented by an infrared emitter or a light emitter. a reflector illuminating the body and thereby increasing the contrast of the reflective markings located at the anatomical points of the head and shoulders. The camera system stand is equipped with one vertical column and one horizontal arm, on the horizontal arm and the vertical column of the stand are two adjustable camera bases. The bases are adjustable so that both cameras can sense reflective markings located on the upper half of the patient's body at different heights. The positioning bases also ensure approximate positioning of the camera's optical axes in the vertical and horizontal directions. Both positioning bases have the possibility of sliding on the stand and tilting around two axes. Two cameras are placed on the adjustable camera bases. The cameras are used to sense rotation, flexion and inclination of the head and to detect rotation and inclination of the shoulders. For cameras placed on adjustable bases, it is not necessary to maintain the position so that the optical axis of the camera placed on the horizontal arm points exactly vertically and the optical axis of the camera placed on the vertical column points

- 2 GB 24514 Ul exactly horizontally, since the position sensors in the three-dimensional earth coordinate system are precisely attached to both cameras.

From the knowledge of the exact position of the cameras detected by the position sensors in the Earth's coordinate system, it is possible to determine the position of the objects scanned by the cameras in space. The software that controls both cameras in the camera images detects the position of the points defined by the reflective markings located at the respective anatomical points of the head and shoulders, which are a total of six on the upper half of the subject's body. In order to identify the anatomical axes of the head and shoulders, reflex marks must be placed on the anatomical points of the body of the person under examination. The markings are placed on the two cartilaginous protuberances of the auricles - the tragus and the two lower edges of the orbits - canthus - orbit. Then there are also two protuberances called acromion, ie the shoulder straps. By identifying the positions of the six reflective marks on the two images of the head and shoulders from two cameras, the angles of the anatomical axes of the head and shoulders relative to the Earth's coordinate system and to each other are determined.

The principle of the proposed solution is that by means of cameras placed on a stand and equipped with sensors of their position in the terrestrial system, images of the top and front views of the patient's head and shoulders are captured to determine the position of the anatomical axes of the head and shoulders. At the bottom of the rack, a platform with marks for positioning the patient's feet is attached to the vertical column of the rack. The platform is structurally positioned so that its center lies below the camera located on the horizontal arm of the stand. The platform is provided with marked foot contours to ensure accurate patient standing during medical examination.

Both cameras and camera position sensors are connected to a computing device, ie a personal computer. The personal computer controls and evaluates data obtained from a measuring system with two cameras and two camera position sensors in space. Based on data on optical characteristics of digital cameras and the position of cameras in space, constants characterizing the system layout are determined. These constants are subsequently used in the computational algorithm to determine the angles of rotation, flexion and inclination of the head and rotation and inclination of the shoulders. Finding angles is based on trigonometric calculations and the position of the detected markers on images of the anatomical points of the patient's body.

The system is designed to allow repeated measurements of patients of different ages and stature. System life is not limited. Replacement is only assumed for reflective marks. The construction of the rack is sufficiently rigid, ie its degradation is not expected. Over time, mechanical parts may be worn to adjust the cameras in space. The system as a whole is simple to operate by one person who only adjusts the desired camera positions and places small reflective markings on the patient in accordance with the position of the anatomical points of the head and shoulders.

Using the PC, the operator performs other tasks for measuring the head and shoulders in the space. Measurement and application of reflective labels is not time consuming and takes approximately two minutes.

Clarification of the figures in the drawings

The device for determining the position of the head and shoulders of a patient according to the present invention will be described in more detail with reference to the accompanying drawings. In FIG. 1 is an axonometric view showing an embodiment of a camera system with cameras for recording the position of anatomical points of the head and shoulders of a patient in 3D space. In FIG. 2 shows a detail of the realized construction of the stand with an infrared radiator, a positionable camera base and a camera with a camera position sensor mounted in space. In FIG. 3 shows a diagram of the camera system during the measurement of the position of the patient's head and arms in a three-dimensional space.

Example of technical solution implementation

For individual figures, the numerical marking of the elements of the realized system construction corresponds as follows. Camera system stand 1 with one vertical column and one horizontal arm. Positionable base 2 of the camera 5 with a vertically oriented optical axis. Positioning base 3 of the camera 6 with a horizontally oriented optical axis. An infrared radiator 4. A camera 5 with a vertically oriented optical axis and a camera 6 with a horizontally oriented optical axis.

- 3 CZ 24514 Ul

Platform 7 with marks for positioning the patient's feet. Computing device 8 of automatic data collection, and identification and evaluation of the position of the head and shoulders in the terrestrial coordinate system, in the form of a desktop personal computer. Reflective marks 9 located at the anatomical points of the patient's head and shoulders. Position sensor 10 of the camera 5 with a vertically oriented optical axis and position sensor 11 of the camera 6 with a horizontally oriented optical axis.

As can be seen from the enclosed FIG. 1; FIG. 2 and FIG. 3, the device consists of a stand and a camera system with one vertical column and one horizontal arm, the stand also forms the supporting structure of the camera system.

Attached to the stand 1 is a positionable camera base 2 with a vertically oriented optical axis and a positionable camera base 3 with a horizontally oriented optical axis. A camera 5 with a vertically oriented optical axis is fixedly fixed to the positioning base 2.

A camera 6 with a horizontally oriented optical axis is fixedly fixed to the positioning base 3. The positioning bases 2 and 3 are positionable so as to provide an approximate orientation of the optical axes of the cameras 5 and 6 in the vertical and horizontal directions, and towards the upper half of the body of the patient to be measured. Both positioning bases 2 and 3 have the possibility of sliding on the stand I and tilting about two axes. The rigid and rigid construction of the stand 1 provides an approximately 90 ° angle between the optical axes of cameras 5 and 6. The cameras 5, 6 are monochrome cameras DMK21AF04.AS IMAGING SOURCE with IR filter, 640x480 pixels, connected to a computing device 8-desktop computer using FireWire cables . The IR filter placed in front of the ka20 mer 5,6 lens transmits only infrared radiation from 850 nm upwards.

To the camera 5 with a vertically oriented optical axis in space, a sensor 10 of the position of the camera 5 in the earth coordinate system is fixed and accurately fixed. To the camera 6 with the horizontally oriented optical axis in space, the position sensor 11 of the camera 6 in the terrestrial coordinate system is fixed and accurately mounted. The 10 and li sensors used are Phidgets USB 9 DoF gyro-accelerometers.

Position sensors 10 and JT provide position information of the cameras 5 and 6 for the automatic data acquisition device 8, and the identification and evaluation of the position of the head and arms in the earth coordinate system, in the form of a desktop computer. Both cameras 5 and 6 are connected to a computing device 8 in the form of a commercially available personal computer.

An infrared radiator 4 is attached to the stand 1 at the top to illuminate the reflective markers 9j located at the anatomical points of the head and shoulders of the patient's body. The infrared emitter 4 used is of the type 2 Redbeam IRD120 and emits 850 nm radiation. Six reflective markings 9 in the shape of a hemisphere with a radius of 2 mm are placed on the cartilaginous projections of the ear lobes - tragus, the lower edges of the orbit - canthus - orbit, and acrromions - the shoulder straps.

Calculation of the angles of rotation, reflection and inclination of the head and rotation and inclination of the shoulders is performed on a personal computer by knowing the coordinate of the points corresponding to the reflective marks 9 located on the anatomical points of the head and shoulders of the patient.

A platform 2 with marks for positioning the patient's feet is attached to the stand 1 at the bottom. The measurement by the camera system is performed so that the patient stands in front of the camera 6 mounted on the vertical column of the stand 1 and below the camera 5 mounted on the horizontal arm of the stand 1, placing the feet on the platform 7 with the foot positioning marks. The physician will then place reflex marks 9 on the patient's body in accordance with the position of the anatomical points on the left and right sides of the patient's head and shoulders. The computing device 8 in the form of a desktop computer automatically transmits to the physician the position of the anatomical axes of the patient's head and shoulders in the 3D earth coordinate system.

The main mechanical component is a camera stand made of stainless steel, weighing approximately 30 kg, since sufficient rigidity of the structure must be ensured. The column height is 3.1 m and the horizontal arm length is 1.8 m. The system is designed to allow repeated measurements of patients of different ages and stature.

System life is not limited. The construction of the stand itself is sufficiently rigid, ie its degradation is not supposed. Over time, mechanical parts for positioning and panning of cameras 5, 6 may wear. Short service life due to degradation,

-4GB 24514 Ul have only reflective marks 9 placed on anatomical points of the head, their price is assuming 100 pcs - 4 thousand. CZK.

The cost of the system construction is low compared to commercial systems, up to 20 thousand. The price of two cameras 5, 6 in sufficient quality is up to 20 thousand CZK. CZK. Prices of sensors 10, 11 detecting the position of cameras 5, 6 in the space is also up to 20 ths. CZK. The total price of the system ranges from 60 to 70 thousand. CZK, which makes the system available to almost all neurological and physiotherapeutic clinics.

Industrial applicability

The camera system for measuring the position of the patient's head and shoulders in a three-dimensional space, according to this technical solution, can be used as a medical examination device in clinical practice. The technology will make it possible to use the system in orthopedics, neurology and rehabilitation to monitor progress in the treatment of the patient and as a system enabling the coordination of correct posture with the focus on the upper half of the body through rehabilitation procedures. The new technology will complement existing motion measurement systems in clinical practice and will extend the possibilities of patient standing examination.

Claims (6)

15 PROTECTION REQUIREMENTS A device for determining the position of the head and shoulders of a patient, in particular for medical applications in neurology and rehabilitation, characterized in that it comprises a stand (1) provided with a first positionable base (2) for a camera (5) with vertically oriented optical axis and sensor (10) its position and a second locatable base (3) for a camera (6) with a horizontally oriented optical axis and a position sensor (11) thereof for profile pictures of a patient provided with at least six hemispherical reflective marks (9) positioned on the anatomical a head and shoulder points and a platform (7) with markings for positioning the patient's feet is attached to the bottom of the stand (1). Device according to claim 1, characterized in that an infrared radiator (4) is connected to the stand (1) to illuminate the reflective marks (9). 25 Device according to claim 1, characterized in that the first positionable base (2) for the camera (5) is movable and tiltable about two axes and the second positionable base (3) for the camera (6) is movable and tiltable about two axes. Device according to claim 1 or 2, characterized in that the position sensor (10) is precisely and firmly attached to the camera (5) and the position sensor (11) is precisely and firmly attached to the camera (6). Device according to any one of the preceding claims, characterized in that the camera (5) with the position sensor (10) and the camera (6) with the position sensor (11) are connected to a computing device (8). Device according to any one of the preceding claims, characterized in that the platform (7) with marks for positioning the patient's feet is attached to the stand (1) and the center of the platform (7) is located below the camera (5).