CA2270837A1 - Device for optically examining and/or treating the human eye - Google Patents

Abstract

A device for optically examining and/or treating a patient's eye has a lighting and/or observation optical unit (3) that can be freely moved and oriented in the direction of all co-ordinates in space above the left or right eye (29) and has a flat area that can be set on the surface of the eye. The optical unit is preferably retained in the adjusted position relative to the eye so as to maintain itself in a fixed position in relation to the patient's head and to move together with the head, when the patient can move his head. The treating doctor thus does not need to carry out manual positioning and/or securing operations while diagnosing and/or treating the patient. On the contrary of known optical treatment devices, unwanted degrees of freedom of motion are excluded by the disclosed device, and the risk of injuries is considerably reduced. In particular, laser beams can be more safely used for treating the eye.

Description

Device for Optically Examining and/or Treating the Human l The invention concerns a device according to~ the preamble of patent claim 1.
Ophthalmologic examinations are preferably carried out using light. During examinations of the human eye, the forehead is typically pressed against a headband arranged on a table and the chin is supported on a chin support that is also arranged on the table. The headband and chin support serve as adjusting elements to immobilize the head of the patient in the examination position. A split lamp pivotally connected to the table is used as an illumination source; the lamp is connected in a suitable manner by means of a so-called biomicroscope. A
contact lens, which the physician holds in the beam path of the biomicroscope and of the split beam are also used in many diagnoses. At the same time, the physician is :required to look through the biomicroscope and ensure that the patient remains in position.

From United States patent 4,477,159 is known a photocoagulator with which the physician, as explained above, holds a focusing or contact len:> with the hand and pushes the same against the surface of the eye. On its head is attached a telescope, with which he can look into the eye of the patient through the hand-held contact lens. The radiation of a laser is faded into the telescope by means of a beam conductor and is then guided out of the telescope to the contact lens as a free beam. Illumination radiation similar to laser radiation can also be guided to the contact lens .
The object of the invention is to make available to the physician a device which allows safe and problem-free examination and treatment of the human eye, preferably using high-intensity laser beams.
The object is attained in that, in contrast with known optical treatment devices, which have illumination and/or treatment optics that are no longer held by the hand of the treating physician on the eye to be treated, they are preferably applicable to the head of the patient. The optics is particularly displaceable manually by the physician (a remote-controlled displacement is of course also possible) and remains in the set position, whereby one of the surfaces of the optic (contact lens) remains applied on the eye surface. The optic is again displaced for a new setting and then remains self supported in the new set position. If the patient moves his/her head, the adopted position remains relatively unchanged relative to each eye. The head of the patient need no longer remain immobile in one position for a long period of time.
Treatments with laser beams (retina coagulation, etc.) can be carried out easily when using the device according to the invention since prolonged alignment of the eye with the radiation source is easily provided. The safety problems which occurred heretofore have thereby been eliminated. The physician also no longer requires a "third" or "fourth" hand for holding the observation or treatment optics.
The holding or guidance arrangement of the fevice according to the invention can also be attached to a free-standing patient head holder, by means of which the head can be held in a defined position by the forehead and chin.
The device should be configured as simply as possible. For this reason, the radiation sources for illumination and particularly for treatment of the eye should be outside of the device and the light or radiation (a form of radiation close to the visible spectral range such as, for example, infrared, is designated as "light" in the following) is guided by means of light conductors (light conductor beam).
Direct observation by means of a microscope is also eliminated in an advantageous manner. An image exposure of the eye including its background, the retina, the chamber angle, or other elements can take place with an image frame system having a CCD chip that weighs merely a few grams. In this way, a savings in weiglht is also obtained. The physician can also observe the patient or the apparatus better and can kf:ep the same under control.
Another advantage of the device according to the invention is that it can be used on a patient who is sitting as well as lying down.
Working with light conductors for guiding illumination energy and treatment energy as well as an image transfer by means of wires results, aside from a considerable savings in weight, in freedom for the patient, since his/her head need no longer be immobilized, for example, on a treatment device arranged on a treatment table. ThE: patient can move his/her head.
Measuring sensors (for example, for measuring eye movement, eye pressure, etc.) can be integrated into or within the device according to the invention in a simple manner.
Light emitting elements such as LEDs can also be integrated into the contact lens.
The device according to the invention can be used in an analogous fashion to the photocoagulator of United States patent 4,477,159 mentioned above. In contrast to the known photocoagulator, with the device according to the invention, the physician no longer carries an optic system on his/her head, which makes him irrunobile and limits his/her field of vision.
Adjustment coordination of an observation and/or treatment optic due to the patient's head movements is no longer needed. Furthermore, the position of the units necessary for treatment is set even though the patient may move. The setting of the laser beam path in a photocoagulation, for example, is particularly advantageous. Inadvertent slipping of the contact lenses or faulty position of the lens, which could cause damage to the eye, is no longer possible.
In the following, examples of the device according to the invention will be described in greater detail with reference to the drawings. Other advantages of the invention result from the following description. In the drawings:
Fig. 1 shows a perspective representation of the device according to the invention;
Fig. 2 shows a variation of the device shown in Fig. 1;
Fig. 3 shows a schematic representation of the components of an optic head of the device shown in Fig. 2, for example;

Fig. 4 shows an enlarged view with respect to the representation of Fig. 2 of a contact lens holder, for example, in the view direction II:I indicated in Fig. 2;
Fig. 5 shows a variation of the optic head shown in. Fig. 3; and Fig. 6 shows a cross section through an embodiment of a contact lens, for example, which can be used in the holder indicated in Fig. 4.
The device according to the invention shown in Figure 1 has a holding part 1 with a housing 3 in which the illumination, observation and treatment devices shown in Figure 4 are located. The device can be placed on the head of the patient.
The holding part 1 has a headband Sa that runs around the head and a holding band Sb, between which the housing 3 is held by means of a so-called swan neck 2. The swan neck 2 is configured in such a way that it holds the housing :3 in pivoted-back position without a spring return. Furthermore, the holding part 1 has a top band 7. One end of the headband Sa, the holding band Sb and the top band 7 run together at one location to the left and right (over the ears in the situation where it is placed on the head) and are held together there by means of a fixing device 6a and 6b.
The headband Sa and the top band 7 are flexible, preferably configured with a padding 9a and 9b. The holding band Sb is rigid. The headband Sa and the top band 7 can be adapted in length to the head shape of the respective patient by nneans of a displacement arrangement 10a or 10b.
Figure 2 shows an embodiment of the device shown in Figure 1. The housing, referred to herein as 3, is removably attached to the holding band Sb with a clamping arrangement 11. It S

can be displaced from one eye to the other in the direction of the double arrow 12 in Figure 2 along the holding band Sb. The removability of tJhe housing 3 allows for its use on the head holder. The housing 3 has a positioning arrangement 13 for a three-dimensional setting of an optic head 15 by means of handles 22a and 22b. 7.'he optic head 15 contains the illumination, observation and optical treatment devices described below.
At approximately the location of the clamping (and displacement) arrangement 11, the housing 3 has a positioning arrangement 13 with a self inhibiting pivoting arrangement 19, which can be stopped with a stop head 20 and can be unlocked by pushing on a head lying on the other side (not shown in Figure 2). Pivoting arrangement 19 makes possible a pivoting around an axis that is approximately parallel to the connection axis of both displacement arrangements 6a and 6b.
In Figure 2, under the pivoting arrangement 19, the positioning arrangement 13 has a self inhibiting displacement direction 21, by means of which the optic head 15 can be displaced vertically to the pivot axis of the pivoting arrangement 19. The displacement arrangement 21 can be fixed by means of a left and right stop lever 22a or 22b. This makes it possible for the treating physician to work with either the left or right hand. Likewise, the stop handle 20 can also be laid out for work with both hands. The optic head 15 itself is also three-dimensionally displaceable and is self inhibiting pivotally held on the ball pivot. The displacement of the optic head 15 serves for fine tuning, particularly during eye examination and/or treatment.
The pivoting and both displacement arrangements are configured to clamp with a spring tension in such a manner that a self inhibition is obtiiined. The spring force for clamping is set along a spectrum ranging from completely loose to firm by means of the stop handle as well as the stop lever.

In Figure 2, on top of the housing 3, the elecaric supply lines, the signal lines, and a light conductor or a light conductor beam 37 described below are gathered into a cable 25 and are guided away by means of a plug 26. The light conductor 37 for the laser radiation is guided away separately, but could also be gathered into the cable 25 by means of another embodiment of the optic head 15. The cable 25 is held by means of a clamp 27 for purposes of stress reduction at the top band 7.
The optic head 15, shown schematically in Figure 2 pushed against an eye 29, has a contact lens 30 on the side nearer to the eye 29. The contact lens 30 held in a tubus 23 has, as shown in Figure 4, for example, an upper and a lower lid deflector 28a or 28b for the upper or lower eyelid. The tubus 23 can have respective adapter or coupling elements for the different contact lenses mentioned below. As an alternative, it can preferably be held in a ring holder.
Different contact lenses are used for certain areas of the eye (retina fundus, retina periphery, chamber angle, etc. ). The surface of the contact lens 30 to be placed on the eye 29 has, as shown in Figure 6 with respect to the embodiment described herein, two different curve radii rF and r~.
The central part 33a of the surface has a smaller curve radius rG than the edge region 33b with rF.
The smaller radius r~ is, depending upon the application area, between 6 mm and 8 mm, and the radius rF is between 10 mm and 14 mm. The ring holder for the contact lens 30 is placed in the tubus 32. Of course, one with only a single radius c;an be used instead of the contact lenses 30 with the both radii rF and rG described herein. The contact lens 30 described herein, however, results in better optical imaging and observation properties.
For illuminating the eye 29, as shown in Figure 3, the illumination radiation is fed by means of the light conductor 37 in the cable 25 and b;y means of a plug 36.
The placement of the illumination source outside of the optic head 15 reduces its weight, facilitates an exchange of the illumination source, produces free space in the optiic head 15 for other units and sensors to be aligned on the eye 29, and also reduces heat generation in the direct vicinity of the eye 29 and the hand or hands of the physician. A beam forming arrangement is also available for the illumination source, which is represented symbolically as a lens 39. A filter arrangement can also be provided for the illumination radiation, which however may also be assigned to an external light source.
The illumination beam 40 passes, after beam forming and an eventual filtering (color, intensity, polarization), a first deflection mirror 41, is then directed onto a focusing lens 44 and from there by means of a contact lens 30 into or onto eye 29. The first deflection mirror 41 is now tempered or arranged so that the radiation of the illumination light is transmitted almost unimpeded (preferably 99 % ); laser radiation as described below, however, is deflected.
Beam splitting can take place by tempering, but also by a suitable selection of the beam paths.
The second deflection mirror 43 allows part (as little as possible) of the illumination radiation to be transmitted and deflects the rest of the radiation toward the lens 44. The laser radiation is here also (almost) completely deflected. The radiation that comes fronn the illuminated areas of the eye is imaged on an image emitting element (CCD chip) 45 as observation arrangement with the lens 44 through the second deflection mirror 43 with a radiation loss of less than 50 % . The electric signals of the image emitting element 45 are displayed as images on a monitor and at the same time are stored in a computer, where they are available for further processing . The computer storage can of course also be eliminated. The monitor can now be configured as an independent (stand-alone) device or as a so-called headband monitor. This small headband monitor would preferably be worn on the head by the treating physician.
If necessary, the electronic image emitting element 45 can be removed and the illuminated inside of the eye or its surface can be observed by means of a microscope (so-called biomicroscope).

Aside from the illumination and observation arrangements, a beam-physical processing arrangement is installed in the optic head 15. The radiation for the processing arrangement is guided by means of a separate light conductor 47 to~ a sensor 49, with which the laser radiation transported by the light conductor 47 is simultaneously direction-manipulated for processing. The sensor 49 can, as indicated in Figure 3, be configured as a three-dimensional pivotable, preferably self inhibiting, ball bearing. Furthermore, a beam forming arrangement 51 for producing different beam cross sections is available for the laser light that comes out of the light conductor 47. The laser radiation is guided toward the eye by means of the mirrors 41 and 43 and the focusing lens 44 as well as the contact lens 30.
A helmet that is pulled over the head of the patient can also be used instead of the above-described device. However, the above device is preferred because it impairs movement less. An advantage of the helmet would be, however, that a hearing capsule could be installed in it with which the patient could listen to music, information, or instructions.
A beam path as shown in Figure 5 can be selected for a non-central processing, for example, in the chamber angle of the eye. A beam forming arrangement 52 (as a rule a settable opener) for the processing laser beam 53 of a laser is indicated symbolically by a lens pair 52.
The imaging optic for the image conversion element, designated herein as 55, is indicated by a lens pair 56. A mirror 57 positioned in the laser beam path is "transparent coated" to the laser radiation (on both sides). The observation beam path 59 deflected by the mirrors 53 and 59 is guided by means of a mirror 61 arranged sideways 1:o the eye axis 62 through a contact lens 65 lying on the eye surface 63 sideways through the chamber angle of the eye. In contrast to the above embodiments, no especially configured beam forming optic must be used for illumination;
the end of a light conductor 66 connected to an illumination source is inserted in such a manner in a breakthrough or in a threaded hole 67 in the contact lens 65 that it comes to lie near the eye surface 63 when the contact lens 65 is in place. (The illumination could be configured as a ring illumination). The contact lens 65 is configured preferably similar to the contact lens 19 [sic].
Correspondingly adapted contact lens optics are used for the regions of the eye which can be observed under preset angles.
The device according to the invention can also be configured as glasses with a face shell similar to goggles instead of the embodiment shown :in Figure 2. In this face shell are integrated the observation, illumination and, if necessary, processing arrangement similar to the above-described embodiment.
Instead of holding the optic head 15 with the: pivot and both displacement arrangements 19 and 21 at the holding band Sb, a mounting can also take place with a so-called swan neck or manipulator. The optic head 15 can also be arranged with a similar swan neck or manipulator on a fixed head holder on which are immobilized the forehead and chin of the patient.
Aside from the above-mentioned contact lens there are a variety of other contact lens embodiments . The above-described optic head 15~ or its tubus 23 can be provided with a corresponding adapter in such a manner that these different contact lenses can be applied (flanged). With these other contact lenses, different enlargements and image fields of different dimensions can be obtained. Contact lenses may also be used which are adapted to the juvenile eye as well as the eyes for persons of various ethnicities.

Depending upon the treatment and examinatiion requirements, the contact lens 30 or 65 may also be eliminated, whereby an observation then takes place by means of the image conversion element 45 or SS belonging to the now-modified optics system.
In Figure 3, the illumination and treatment beams (laser) are gathered by means of the mirror 41 into one beam path, which is then superposed with the observation beam by means of the mirror 43. In Figure 5 are gathered the treatment and observation beams by means of the mirror 57. The illumination takes place by means of a separate beam path. The illumination, observation, and treatment beam paths may, depending upon need, be gathered or split by beam-gathering or beam-splitting elements, among others by using spectral filters.
A gathering and splitting can also be undertaken by using beam polarization. As splitting and gathering elements, aside from the described mirrors, beam splitting prisms or binary optics can be used.
If a semiconductor laser is used, then the same can already be integrated into the optic head 15, whereby the light conducting supply 47 would be eliminated. However, the increased weight as well as the additional space requirement must be taken into consideration.
Additional electric energy supply cables must also be available for the laser.
The device according to the invention can be easily operated in such a way that it can be used not only for the treatment of humans but also for animals, whose movements are often unpredictable.

Claims (9)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS.

1. Device for optical examination and/or treatment of the eye (29) of a patient with an illumination and/or observation and/or treatment optic (3, 15, 30) that can be freely displaceable or adjustable for the left or right eye (29) in all space coordinates, with a holding device connected to the head of the patient that can be held self-supported and rigid with respect to the head of the patient in the set position with respect to the eye (29), but that can be displaceably held, characterized in that the optic (3, 15, 30) has a surface area (33a, 33b) with an optical effect that can be applied to the surface of the eye for ophthalmologic examination and/or treatment, whereby the treating physician is freed during diagnosis and/or treatment from manual positioning and/or holding manipulations and can thereby preferably concentrate his attention on manipulation of the observation and/or treatment radiation.

2. Device according to claim 1, characterized by a holding arrangement (1, 11, 13) for the illumination and/or observation optic (3) with at least one holding headband (5a, 5b, 7) that can be placed rigidly on the freely moving head of the patient so that the optic can follow the movements of the head.

3. Device according to claim 2, characterized in that the illumination and/or observation optic (15, 30) is/are arranged in the housing (3), which is self supporting and self-inhibiting, but displaceable together with the holder arrangement (1, 11, 13), and the holder arrangement (1, 11, 13) has a swan neck or manipulator connected to a headband (5a, 5b, 7).

4. Device according to one of claims 1 to 3, characterized in that the optic (15, 30) has a contact lens (65) on which a light emitting element (66, 67, 37) is arranged.

5. Device according to one of claims 1 to 4, characterized in that the optic (15, 30) has a contact lens which can be exchangeably held in the housing (3) for inserting contact lenses (30, 65) for the different eye regions.

6. Device according to one of claims 1 to 5, characterized in that a superposing component (41, 43; 57) for superposing or splitting the illumination and/or observation radiation and/or treatment radiation is adapted to at least two of the illumination, observation, and optic treatment arrangements.

7. Device according to one of claims 1 to 6, characterized in that the illumination and/or observation radiation is guided by means of light conductors (37, 47).

8. Device according to one of claims 1 to 7, characterized in that an electronic image playback arrangement and a removable image emitting element (45; 55) are assigned to an observation arrangement, which converts the optic observation image into electronic signals for the image playback arrangement.

9. Device according to claim 8, characterized in that the image emitting element is removably held in an adapter, which makes possible the use of a microscope when the image emitting element is removed.