WO2007104870A2

WO2007104870A2 - Ultrasound device for ultrasound measurements of the eye, and probe used by this device

Info

Publication number: WO2007104870A2
Application number: PCT/FR2007/000457
Authority: WO
Inventors: Martin Charles
Original assignee: Quantel Medical
Priority date: 2006-03-16
Filing date: 2007-03-16
Publication date: 2007-09-20
Also published as: AR056284A4; WO2007104870A3

Abstract

The ultrasound device according to the invention comprises a probe (1) with a proximal end and a distal end. Arranged on the distal end of this probe, there is a light beam emitter (4) which is positioned axially and oriented opposite the probe 1. This device also provides a reference point which is intended to be fixed by the patient and with which the light point generated by said emitter is brought into coincidence. This device makes it possible to reduce the margin of error in the diagnostic procedures performed.

Description

US ECHOMETRIQUE DEVICE FOR PERFORMING OCCULAR ECHOMETRIATE MEASUREMENTS AND PROBE USED THEREBY.

The present invention relates to an ultrasound probe, usable in particular, in an ocular echometer for performing echometric measurements of the eye, such as the axial length between cornea and macula (central vision of the retina).

As is known, to produce a type A biometric scanner image, the operator must support with one hand the probe with which he comes into contact with the cornea to obtain the longitudinal axial measurements that can be used to calculate the power of the the intraocular lens. This study aims to measure the distance between the cornea and the macula (specialized area of the retina for fixation). This can be done in two ways, the first is contact ultrasound, in which the tip of the ultrasound comes into direct contact with the cornea, and the second is the immersion echometer, which is placed between the two eyelids. cup filled with methylcellylose. The probe is then placed in contact with the methylcellulose and the measurement is made.

One of the disadvantages of this type of measurement lies in the difficulty of making the echo measurement axis coincide with the axis of vision. Currently, the operator must ask the patient to fix his gaze on a point, remotely, having to position the probe _s as precisely as possible in the visual axis of the eye to be examined. Unfortunately, this type of measurement methodology generates a vast spectrum of error, which can lead to errors in the calculation of the intraocular lens. In order to reduce this margin of error, the operators use a solution consisting in carrying out a multiplicity of measurements and then determining the average value of these measurements, in order to be able to make a diagnosis as accurate as possible.

The invention is therefore more particularly intended to reduce the margin of error in the measurement of the axial length of the eyeball,

It proposes for this purpose a probe used in the echometry technique of the type used in an echometer to perform echometric measurements, this probe comprising a proximal end and a distal end; according to the invention a light beam emitting element is disposed distal end of said probe, said emitter element being axially positioned and oriented opposite said probe.

Embodiments of the invention will be described below, by way of non-limiting examples, with reference to the accompanying drawings in which:

Figure 1 shows a probe according to the invention;

Fig. 2 shows a modified echometer for using the probe of Fig. 1;

Figure 3 is a diagram showing the application of the probe at the time of performing the corresponding measurement.

FIG. 4 is a schematic axial section of a probe equipped with a light beam emitter consisting of a laser diode. As shown in FIG _I5 the probe according to the invention which carries the general reference numeral 1, is intended to be connected to a echometer of the type illustrated in Figure 2. The probe 1 comprises a distal end 2 and one end proximal 3. On said distal end 2, is disposed a light beam emitting element 4. Said light beam emitting element 4 has a substantially cylindrical shape and comprises a laser beam emitter which is connected to said probe by a receiving sheath 5.

This receiving sheath 5 does not serve only as a remoter fixing element 4 with the probe 1: it furthermore comprises an actuating lever 6 which controls the laser light beam remuster 4.

Figure 2 shows an echometer 7 which has been modified so that the probe object of the invention can be fully used. Indeed, and as explained below in relation to the measurement methodology, said echometer 7 has been modified in order to incorporate a rearview mirror 8, which makes it possible to visualize the light point emitted by a laser light beam remover 4 on a surface appropriate S, without the operator having to turn to visualize said generated light point. It should be noted that although a mirror 8 has been used to obtain a better result from the use of the probe 1, the use of said mirror 8 should not be considered as limiting, it being understood that said mirror 8 can be replaced by any device for obtaining an image of the laser light point "for example a camera and a monitor, said mirror 8 may not even be incorporated in the ultrasound.

FIG. 3 illustrates a mode of use and application of the probe 1 according to the invention. First of all, the operator who wishes to perform an echometric measurement on a patient must first actuate the transmitter of laser light beam 4 by means of a slight rotation of the lever 6 incorporated in the sheath 5. Once the laser light beam transmitter 4 is turned on, the operator positions the proximal end 3 of the probe 1 on the cornea of the eye 9 to be measured, as commonly done in practice, the patient fixed with the other eye 10 the light point 11 generated by the laser transmitter 4 on a surface S located for example at a distance D of 2 m. Thus, it is possible to align the axis of vision of the patient with the axis of the probe of the echometer, as shown in FIG.

In the case of the seated patient, it is possible to use a fixed point to initially orient the patient's gaze and to bring the light point projected by the laser onto it. In that case. the operator controls through the mirror 8 that the light point formed by the laser pointer coincides well with the fixed reference point.

In the case of the patient lying down, the procedure is simpler, the patient looks at the ceiling. The probe is positioned vertically and projects the beam into the patient's field of vision. The fixed point is no longer essential.

In the example illustrated in FIG. _4S, the light beam emitter 4 comprises a red laser diode 12 mounted in a tabular section 13 which extends substantially from one end to the other of the probe. At the level of the diode 12, the section 13 is coated with an opaque material 14 which partially closes the section 13. The laser light beam generated by the diode 12 then passes through a coaxial calibrated hole 15 made in the aforesaid material. Optionally, this hole 15 may contain a section of optical fiber. Advantageously, the control of the laser diode 12 can be provided by the ultrasound system at the time of acquisition of the measurements. On the opposite side of the diode 12, this tabular section contains the emitter / receiver element ER of the probe. This provision makes it possible to obtain a perfect coaxiality of the light beam generated by the diode and the transmitter / receiver element.

Claims

1. An echometer probe for use in echocardiographic measurements, said probe (1) comprising a proximal end and a distal end, characterized in that a light beam emitting element (4) is disposed on the distal end of said probe (1). ) positioned axially and facing away from said probe (1).

2. Probe according to claim 1, characterized in that said light beam emitting element (4) has a substantially cylindrical shape.

3. Probe according to claim 1, characterized in that the light beam consists of a laser beam.

4. Probe according to claim 1, characterized in that the vibrating beam emitting element (4) is connected to said probe (1) by a receiving sheath (5).

5. Probe according to claim 4, characterized in that said receiving sheath (5) comprises a control lever of the light beam remuster (4).

6. Probe according to claim 1, characterized in that said light beam emitting element (4) and said probe (1) define a single body.

7. Probe according to claims 1 and 6, characterized in that said light beam emitting element (4) is operated remotely _} or controlled by the echonite on which is connected the probe. The ignition of the laser being reduced to the image acquisition phase.

8. Ocular echometric measuring device, characterized in that it involves on the one hand a probe (1) having a proximal end intended to be positioned facing the cornea of the eye of a patient and a distal end provided with a light beam emitter (4) positioned axially and facing away from said probe (1) and secondly a reference point to be fixed by the patient and on which the point is brought into coincidence light generated by said transmitter.

9. Device according to claim 8, characterized in that it further comprises viewing means such as a rearview mirror (8) or a camera / monitor assembly for obtaining an image of said light point and said reference point of way to obtain the aforementioned coincidence.

10. Device according to claim 9, characterized in that the said display means are incorporated in the echometer connected to the probe.