GB2474646A

GB2474646A - Eye injection guide means

Info

Publication number: GB2474646A
Application number: GB0918347A
Authority: GB
Inventors: John David Huggan
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-10-20
Filing date: 2009-10-20
Publication date: 2011-04-27
Also published as: GB0918347D0

Abstract

Intra-ocular injection apparatus comprising a needle guide 18 with plurality of stabilizing arms 22/24 attached. The legs 22/24 are adapted to be placed against the surface of an eye. There may be at least two stabilizing arms. The needle guide may be an open ended cylinder with a hollow bore 20. The lumen 20 of the needle guide 18 may be wide enough to accommodate a needle or a needle and syringe. The guide 18 may be translucent. The centre point of the bore may correspond with a needle penetration point pars plana in the sclera of the eye. The support arms 22/24 can radiate transversely outwards from the guide 18. One support arm 24 can be longer than the other arms 22. The arms may be curved for mating bearing on the eye. First and second arms may have a curved edge to be positioned adjacent the limbus of the eye.

Description

MEDICAL APPARATUS

The invention relates to medical apparatus, and in particular to an ophthalmological apparatus, which is used for facilitating intraocular injection.

The invention extends to methods for carrying out an intraocular injection.

Intraocular injection is a technique used by ophthalmologists to inject compounds, such as pharmaceuticals or antibiotics, into the eye of a patient, in order to treat an eye disease or infection. Intravitreal injection is the term given to administering the active agent directly into the vitreous humor of the patient.

As new pharmacological treatments for eye diseases are developed, ophthalmologists are facing the responsibility of providing an increasing number of intraocular injections of pharmacological agents to patients. However, numerous difficulties are encountered when conducting an intraocular injection, which means that only highly trained surgeons are currently able to carry out the procedure.

Clearly, it is imperative that the needle of the syringe used to inject the pharmaceutical agent into the eye must be very accurately placed on the surface of the eye prior to its insertion, and this has been found, by many practitioners, to be difficult. Furthermore, it is also essential to carefully control the direction and orientation of the path taken by the needle as it is inserted into the eye and into the vitreous humor where the agent is released, and this is also a difficult task requiring expertise by the medical practitioner. It is also important that the depth of needle insertion is carefully controlled to ensure that the needle is not inserted too far into the vitreous humor, and again, this requires skill and technique on behalf of the surgeon.

Further problems encountered when carrying out intraocular injections are that there is little physical control of the position of the eye during the procedure other than this having to be maintained in a particular direction, and held motionless, by the patient at the surgeon's request. It is difficult for the patient to maintain their eye in a particular position, and to keep it still as the injection is Jo administered, and this can cause inadvertent ocular damage from random movement of the eye. Thus, the technique of intraocular injection itself may cause discomfort to a patient, and a number of possible complications.

A number of devices exist which have been designed in an attempt to help ophthslmologists carry out intraocular injections. However, such devices are bulky and cumbersome, and therefore complicated to use. Problems associated with such devices are that they do not permit the accurate placement of the needle on the surface of the patient's eye, or accurate insertion of the needle into the eye itself and thus are prone to causing ocular dsmsge. Furthermore, due to their bulky size, these known devices are cumbersome to use and have a large footprint', which results in excessive pressure being placed on the surface of the patient's eyeball as the injection is carried out This results in pressure being applied to the muscle tendons in the eye, which causes discomfort to the patient, thereby msking it difficult for them to keep their eye in a fixed position during the procedure.

There is therefore a need in the art to provide an improved intraocular injection apparatus, and a method for carrying out an intraocular injection. The inventor has developed a much less cumbersome device which guides not only the accurate placement of a needle on the anterior surface of an eye, but also the correct direction, orientation and depth of the path taken by the needle for intraocular drug injection in clinical ophthalmology. This provides less invasive and uncomfortable contact between the device and the eye, without losing the good and wide contact that is necessary to stabilize the eye so as to avoid the possible risks of potential inadvertent movement of the eye by the patient during the procedure.

In a first aspect, there is provided an apparatus for intraocular injection, the apparatus comprising needle guide means and a plurality of stabili2ing arms attached thereto, wherein, in use, the stabi1bing arms are adapted to be placed against the surface of an eye, and the guide means is adapted to guide a needle towards the eye.

The inventor has found that the stabilizing arms of the apparatus provide support for the needle as it is advanced towards the eye via the guide means.

The apparatus may comprise at least two stabilizing arms, or at least three stabilizing arms.

The provision of three stabilizing arms forms a stable tripod arrangement, which provides an anti-rocking safety mechanism on the surface of the eye (i.e. the sclera), while avoiding the application of excessive pressure on the muscle tendons in the eye. The needle guide means provides a rigid element with respect to the stabilizing arms, and is unable to rock off its perpendicular axis with respect to the eye, or bend or twist with respect to any of the stabilizing arms, when in use. This ensures that the needle is advanced in the correct direction with respect to the radius of the globe (i.e. eye ball) and to the correct depth into the eye. The guide means also allows the introduction of an advancing needle at a pre-determined radial distance from the limbus of the eye into the pars plana region. Furthermore, the apparatus stabilises the position of the eyeball during the injection, thereby preventing inadvertent ocular damage caused by random movement of the eye.

The needle guide means may comprise a cylinder having open-ended proximal and dista' ends, which are interconnected by a bore or lumen. The cross-section of the cylinder may be substantially circular. In one embodiment (which is illustrated in Figure 6), the lumen of the guide means may have a width which is sufficient to receive just the needle connected to a syringe. In this embodiment, the lumen may have a diameter of between about 0.1mm and 2mm, preferably between about 0.2mm and 1mm, and most preferably between about 0.4mm and 0.6mm. However, in another embodiment (see Figure 5), the lumen in the needle guide means may be wide enough to accommodate a syringe and its needle coupled thereto. In this embodiment, the lumen may have a diameter of between about 2mm and 10mm, preferably between about 4mm and 9mm, preferably between about 6mm and 8mm. The distal end of the guide means may taper inwardly.

In some embodiments, the needle guide means may be substantially translucent, thereby enabling a user to see the needle or syringe in the lumen, and thereby follow its position towards the eye. Thus, the guide means may be made of a substantially translucent plastic material or the like.

Suitably, the length of the guide means may be between approximately 30mm and 60mm, more suitably between approximately 35mm and 50mm, and most suitably between approximately 40mm and 45mm. Suitably, the diameter of the guide means may be between approximately 2mm and 20mm, more suitably between approximately 4mm and 10mm, and most suitably between approximately 5mm and 8mm. A centre point of the lumen at the distal end of the guide means may substantially correspond with the position of a needle penetration point pars plana in the sclera of the eye, when the apparatus is in use. The needle penetration point is preferably about 3.5mm from the limbus in the sclera for an eye following cataract extraction, or about 4mm in an eye which has not undergone cataract extraction.

The plurality of stabilizing arms may radiate transversely outwardly from a side wall of the needle guide means, and preferably from at least adjacent the distal end thereof.

The arms may extend substantially perpendicularly away from the side wall of the guide means. Preferably, the arms are substantially spaced apart. This improves the stability of the apparatus when in position on the eye.

In embodiments where the apparatus comprises three stabilizing arms, first and second stabilizing arms may be substantially the same length as each other, and a third stabilizing arm may be longer than the first and second arms. Thus, suitably, the length of the first and second arms may be between approximately 2mm and 8mm, more suitably between approximately 3mm and 6mm, and most suitably between approximately 3mm and 5mm in length. Suitably, the length of the third arm may be between approximately 3mm and 12mm, more suitably between approximately 4mm and 10mm, and most suitably between approximately 5mm and 7mm in length. The stabilizing arms may be between approximately 2mm and 6mm wide, or between about 3mm and 5mm wide. The arms may be between approximately 1mm and 3mm thick.

Suitably, the angle formed between the longitudinal axes of the first and second arms may be between approximately 120° and 170°, more suitably between approximately 130° and 165°, and even more suitably between approximately 140° and 160°. In one embodiment, the angle formed between the longitudinal axes of the first and second arms may be approximately 150°, which approximately corresponds to the curvature of the circumference of the limbus.

Suitably, the angle formed between the longitudinal axis of the third arm and the longitudinal axes of the first and second arms may be between approximately 90° and 130°, more suitably between approximately 95° and 120°, and even more suitably between approximately 100° and 110°.

It is preferred that the stabilizing arms comprise an eye bearing surface having a curved shape for matingly bearing on the outer surface of the eye. Thus, the arms may be curved with respect to their horizontal plane, as shown in Figures 5 and 6, such that they form a curved or concave lower surface. The concave lower surfaces may be formed as the arms extend transversely away from the side wall of the guide means and curve away from the proximal end of the guide means, preferably towards the longitudinal axis thereof. The curvature of the curved lower surfaces may be that of a circle having a radius which is substantially the same as that of the eye. For example, the radius of the curvature of the curved lower surfaces may be between about 9mm and 15mm, or between about 10mm and 14mm, or between about 11mm and 13mm.

The concave surfaces ensure that when the apparatus is in use, the stabilizing arms closely contact the anterior surface of the eye, thereby provide a stable base for the device as the injection is administered.

Preferably, the first and second stabilizing arms comprise an edge, which, in use, is adapted to be positioned approximately adjacent the limbus of the eye, which delimits the cornea and the sclera. Thus, the two arms may be curved with respect to their vertical axes, as shown in Figures 3 and 4. Curvature about the vertical axes of the two arms may form a substantially continuous surface, which provides a profile corresponding to the curvature of the limbus on the patient's eye. The curvature of the curved surface is that of a circle having a radius which is between about 4mm and 7mm, and preferably between about 5mm and 6mm. The continuous surface ensures that the apparatus may be placed approximately adjacent the limbus, and this serves two functions. Firstly, it enables the introduction of a needle at the pre-determined radial distance from the limbus of the eye into the pars plana region. Secondly, it prevents movement of the eyeball during injection, thereby avoiding inadvertent ocular damage.

Suitably, the circumferential length of the two arms following the curvature of the limbus may be between approximately 6mm and 10mm when measured from the tip of one of the arms to the tip of the other arm, and more suitably between about 7mm and 9mm. When the apparatus is in position on the eye, the tip of the third arm may be between approximately 8mm and 15mm away from the limbus, preferably between about 10mm and 14mm from the limbus.

The inventor envisages providing an intraocular injection kit for use by ophthalmologists.

Therefore, in a second aspect, there is provided a kit for intraocular injection, the kit comprising the apparatus of the first aspect, and a syringe.

Preferably, the syringe is connected to the apparatus of the first aspect. The syringe may be inserted into the lumen of the needle guide means. The syringe may be connected to the apparatus by a friction fit.

The apparatus or kit may be used for conducting an intraocular injection.

Thus, in a third aspect, there is provided the apparatus of the first aspect or the kit of the second aspect, for use in intraocular injection.

The injection may be an intravitreal injection.

The inventor has devised new methods for guiding a needle into the interior of an eye, and for administering an active agent or medicament to a patient's eye by injection.

Hence, in a fourth aspect, there is provided a method of guiding a needle into the interior of a subject's eye, the method comprising the steps of:- (i) positioning the apparatus of the first aspect, or the kit of the second aspect, on a subject's eye; and (ii) guiding a needle through the guide means until the tip of needle is positioned in the interior of the eye.

In a fifth aspect, there is provided a method of administering, to a subject in need of treatment, a composition comprising an effective amount of a medicament for treating a condition of the subject's eye, the method comprising the steps of:- (i) positioning the apparatus of the first aspect, or the kit of the second aspect, on a subject's eye; (ii) guiding a needle coupled to a syringe containing the composition through the guide means until the tip of needle is positioned in the interior of the eye; and (iii) expelling the composition into the interior of the eye.

Step (i) of the methods of the fourth and fifth aspects may comprise arranging the guide means substantially perpendicularly with respect to the eye so that it contacts an anterior surface of the subject's eye. Step (i) may comprise arranging the guide means such that a concave surface of the first and second stabili2ing arms conforms around the limbus of the subject's eye. Step (i) may further comprise arranging the guide means such that a concave lower surface of each stabili2ing arm conforms with the curvature of the globe of the eye ball. Thus, each lower curved surface of each arm contacts the sclera, thereby fixating the globe and splinting the conjunctiva.

The methods may comprise holding the needle guide means with the user's non-dominant hand, and holding a syringe with the user's dominant hand. The methods may comprise guiding the needle of the syringe into the lumen of a proximal end of the guide means. When using an embodiment of the apparatus in which the diameter of the lumen of the needle guide means is wide enough to accommodate a syringe, as well as a needle coupled thereto, the methods comprise inserting the syringe and needle into the guide means and advancing the needle and syringe therealong, preferably until the hub of the needle contacts the sclera. When using an embodiment of the apparatus having a lumen, which is only just wide enough to accommodate a needle, the methods may comprise inserting just the needle into the guide means, and advancing it therealong, preferably until the needle contacts the sclera. In embodiments in which walls of the guide means are translucent, the method may comprise viewing the needle and/or syringe in the lumen such that its position towards the sclera may be followed.

Preferably, the dimensions of the lumen of the guide means allow the tip of the needle to engage and pierce the sclera of the eye at the correct radial distance from the limbus. The firmness of the eye resulting from its gentle, even and steady fixation by the apparatus affords slightly increased scleral pressure against which to push the needle tip as its insertion through the sclera is begun. The apparatus is preferably substantially rigid for its design to allow the guide means to remain, without deviation, aligned with the radius of the whole eye during the procedure.

The user may then release the composition into the eye in step (iii) of the method of the fifth aspect, preferably into the vitreous humor, using the plunger on the syringe. The methods preferably comprise a final step of withdrawing the apparatus, syringe and/or needle away from the subject, preferably together in one movement.

A "subject" may be a vertebrate, mammal, or domestic animal, and is preferably a human being. The medicament may be any active agent which is suitable for treating a condition or disease of the eye. For example, the medicament may be an antibiotic, or a pharmaceutical, for example an anti-angiogenic agent, an anti-inflammatory agent or a steroid.

All of the features described herein (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined with any of the above aspects in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings, in which:-Figure 1 shows a schematic front view of an eye; Figure 2 shows a partial cross-sectional side view of the eye shown in Figure 1; Figure 3 shows a cross-sectional perspective view of one embodiment of an intraocular injection apparatus or guide in accordance with the invention; Figure 4 shows an end view of the apparatus shown Figure 3 from above in position adjacent the eye; Figure 5 shows a side view of a first embodiment of the apparatus in position on the eye; Figure 6 shows a side view of a second embodiment of the apparatus in position on the eye; and Figure 7 shows a perspective view of the second embodiment of the apparatus in position on the eye.

Example

Figures 1 and 2 show front and side views of a patient's eye 2, respectively, and Figure 3 shows one embodiment of an intraocu'ar injection apparatus 16 according to the invention for treating the patient's eye. The apparatus 16 may be referred to as an -10 -intraocular or intravitreal injection needle guide. Figures 4 to 7 illustrate various views of embodiments of the apparatus 16 in use, when in position on the surface of the patient's eye 2, for example when administering an active agent, such as an antibiotic, or a pharmaceutical, for example an anti-angiogenic agent, an anti-inflammatory agent or a steroid, thereto.

Figures 1 and 2 are provided to assist the reader understand the anatomy of the eye 2, and to help explain how and where the apparatus 16 is positioned on the eye 2 when carrying out an intraocular or intravitreal injection. As shown in the Figures, the eye 2 has an inner, circular pupil 4 through which light passes, and a convex lens 14 disposed directly thereunder by which the light is focused on to the retina (not shown). A pigmented iris 6 extends concentrically around the pupil 4, and, in an adult, the radius of the combined pupil 4 and iris 6 is approximately 5.5mm in width. The white portion making up the rest of the eye 2 is known as the sclera 8, and the circular junction between this sclera 8 and the outer diameter of the iris 6 is referred to as the limbus 10.

The circumference of the limbus is about 36mm in an adult eye, and so the length of one quadrant (i.e. one quarter) of the limbus 10 is approximately 9mm.

Figure 1 also shows, with an X', the site at which an intraocular injection must be carried out in the sclera 8, using a syringe 28 and needle 30 in combination with the apparatus 16 of the invention, in order to deliver the pharmaceutical agent to the eye 2.

The injection site X' is in the pars plana region of the eye, which is approximately 3 to 5mm from the limbus 10, depending on whether the eye has had a previous cataract extraction. In general, the injection site X' is about 3.5mm from the limbus 10 in the sclera for eyes following cataract extraction or about 4mm in eyes not having undergone cataract extraction, and usually towards the outer region of the eye 2. Thus, it is envisaged that two sizes of the apparatus 16 may be required, one for use on eyes that have had a cataract extraction, and another for use on eyes that have not have a cataract extraction.

As shown in Figure 2, when viewed from one side, the anterior portion of the eye 2, consisting of the pupil 4 and iris 6, forms a lobed profile. The lobe is created by the presence of the aqueous humor 32, which is disposed between the iris 6 and an outer -11 -protective coating known as the cornea 12. Posterior to the lens 14, there is provided a vitreous humor 34, which is where the pharmaceutical agent is usually delivered through injection site X', as shown in the Figures.

Referring to Figure 3, there is shown the structure of the apparatus 16 of the invention.

The apparatus 16 consists of a cylindrically-shaped needle guide 18, which is about 40mm in length and between about 4mm to 11mm in diameter depending on the embodiment, which will be described in more detail hereinafter. The needle guide 18 has proximal and distal ends, 1 8a, 1 8b, respectively, which are both open-ended and connected by a hollow bore or lumen 20, which extends through the centre of the guide 18 between ends 18a, 18b. In one embodiment, the wall of the needle guide 18 is approximately 0.5mm thick. As shown in the Figure, the centre point 26 of the lumen at the distal end 1 8b of the guide 18 corresponds to the needle penetration point X' in the sclera 8 of the eye 2, when the apparatus 16 is in use.

The apparatus 16 has three space apart, stabilizing projections, flanges or arms 22, 24, which radiate transversely (and substantially perpendicularly) outwardly from a side wall of the distal end 1 8b of the needle guide 18. Two of the stabilizing arms 22 are the same length as each other (i.e. about 4mm in length), whereas the third stabilizing arm 24 is longer than the other arms 22, and is approximately 6mm in length. The angle formed between the longitudinal axis of the long arm 24 and the longitudinal axes of each of the two shorter arms is about 105°. The angle formed between the longitudinal axes of the two shorter arms is about 1500, which approximately corresponds to the curvature of the circumference of the limbus 10. All three of the arms 22, 24 are approximately 4mm wide and about 2mm thick, and are provided to stabilize the apparatus 16 on the sclera 8 of the eye when in use, as is described in more detail below.

With reference to Figure 3, the two shorter arms 22 and the longer arm 24 are all curved with respect to their horizontal plane, such that the shorter arms 22 and longer arm 24 form curved or concave lower surfaces 22a, 24a, respectively. The concave surfaces 22a, 24a are formed as all three arms 22, 24 extend transversely away from the side wall of the guide 18, but towards the longitudinal axis of the guide 18 beyond its -12 -distal end 1 8b. The angle or radius of curvature of the curved lower surfaces 22a, 24a of arms 22, 24 is substantially the same as the curvature of the eye ball or globe (as shown more clear in Figures 5 and 6), i.e. about 24mm in diameter, such that, when the apparatus 16 is in use, the lower surfaces 22a, 24a of arms 22, 24 closely abut the surface of the eye ball (i.e. the sclera). Thus, the curvature of the curved lower surfaces 22a, 24a is that of a circle whose radius is that of the eye, i.e. about 12mm. In addition to being curved with respect to their horizontal plane, the two shorter arms 22 are also curved with respect to their vertical axes, as shown in Figure 3. Curvature about their vertical axes, forms a smooth continuous surface 22b, which provides a profile enabling the two arms 22 to follow the curvature of the limbus 10 on the patient's eye. The circumferential length of the two shorter arms 22 following the curvature of the limbus is about 8mm when measured from the tip of one of the arms 22 to the tip of the other arm 22. When the apparatus 16 is in position on the eye 2, the tip of the longer arm 24 is about 12mm away from the limbus.

Referring to Figure 4 to 7, there are shown various views of the apparatus 16 in position on a patient's eye 2. The distal end 1 8b of the guide 18 and the arms 22, 24 are placed on the anterior surface of the eye 2. As shown in Figure 4, the apparatus 16 can be seen resting on the eye's sclera 8 with the three stabilizing arms 22, 24 forming a stable base by means of its tripod structure. The inner curved surface 22b of the two shorter stabilizing arms 22 closely abuts the eye's limbus 10, and the longer stabilizing arm 24 extends away from the limbus 10 towards the outer corner of the patient's eye. In positioning the apparatus 16 in this manner, the centre point 26 of the lumen 20 of the cylindrical guide 18 can be seen in direct alignment with the needle penetration point X' in the sclera 8 since the guide 18 extends perpendicularly away from the globe of the eyeball, centred over point X'.

Referring to Figures 5 and 6, there are shown two different embodiments of the apparatus 16a, 16b. The general design of the two embodiments 16a, 16b are essentially the same, with the main difference being the diameter of the needle so guide 18, and the lumen or central bore 20 width. As shown in Figure 5, in one embodiment of the apparatus 16a, the diameter of the lumen 20 of the needle -13 -guide 18 is wide enough to accommodate the hub section 32 of a syringe 28.

Hence, in this embodiment, the diameter of the guide 18 is about 9-11mm to provide a 7mm diameter lumen to accommodate the syringe 28. In use, the vertically arranged needle guide 18 is held by the surgeon in such a way that the concave surface 22b of the two shorter arms 22 conforms around the limbus 10, while all three curved surfaces 22a, 24a of all three arms 22, 24 rest evenly on the sclera, thereby fixating the globe and splinting the conjunctiva. A standard lml syringe 28 (holding 0.lml of fluid for injection), held with the mounted needle 30 in the surgeon's dominant hand, is passed into the lumen 20 of the proximal end 1 8a of the needle guide 1 8. The dimensions of the lumen 20 allow the tip of the needle 30 to engage and pierce the sclera 8 at the correct radial distance from the limbus 10, at point X'.

The firmness of the eye 2 resulting from its gentle, even and steady fixation by the apparatus 16 affords slightly increased scleral 8 pressure against which to push the needle 30 tip as its insertion through the sclera 8 is begun. The apparatus 16 is substantially rigid for its design to allow the guide 18 to remain, without deviation, aligned with the radius of the whole eye 2. In this embodiment, the walls of the guide 18 are translucent to allow the surgeon to see the needle 30 in the lumen 20, and thus, follow its position towards the sclera 8.

The hub 32 of the advancing needle 30 eventually comes to rest against the sclera 8, and its 10mm length in the eye 2 brings it to rest with its tip in the mid-vitreus for the injection at which point the pharmaceutical agent is released, followed by the withdrawal of the apparatus 16, syringe 28 and needle 30 together in one movement.

In a second embodiment, which is shown in Figure 6, the apparatus 16b has a lumen 20, which is much narrower than in the first embodiment 16a, and is only just wide enough to accommodate the needle 30 (for example a 30 gauge needle) of the syringe 28. Thus, in this embodiment, the guide 18 is about 4-6mm in diameter to provide a 0.5mm diameter lumen 20 to accommodate the needle 30 only. Referring to Figure 7, the second embodiment of the apparatus 16b is -14-shown in position on a patient's eye, with the needle 30 of the syringe 28 about to be inserted into the lumen 20 of the needle guide 18.

Using this embodiment of the apparatus 16b, the needle 30 is inserted into the lumen 20 of the guide 18 and pushed down until its tip contacts the sclera 8.

The walls of the guide 18 are translucent in this embodiment also in order to enable the surgeon to see the needle 30 in the lumen 20.

The needle guide 18 is long enough to be held in the non-dominant hand, fixed at its base to the arms 22, 24 and having a central bore 20 of width which is just enough to admit a 30 gauge needle which has a length from hub 32 to tip which is the same as the length of the guide 18 itself, plus 1mm (scleral thickness), plus the desired intraocular length of the needle when in the eye for the injection (about 10mm). The length of the needle 30 therefore needs to be about 55mm long so that it not only extends through the lumen 20, but also has sufficient length to pass into the eye 2 itself. With the apparatus 16 at the correct position and the needle 30 guided down the lumen 20 of the guide 18 until it touches the eye, the radial orientation is set to be in the correct direction for penetration through the sclera 8 into the vitreous 34. Then, when the hub 32 of the needle comes to stop at the top of the guide 18, the needle 30 is in the correct position for the syringe plunger to be pressed to make the injection.

Advantages of the apparatus 16 reside in the fact that is provides exquisite support for the syringe 28 and/or needle 30. The concept of the tripod formed by the spaced-apart arms 22, 24 effectively achieves an anti-rocking safeguard, while avoiding the application of excessive pressure on the muscle tendons, a problem suffered by prior art devices. The posterior portions of the three arms 22, 24 end approximately 12mm from the limbus, lying between tendons and giving good stability. The tripod provided by the three stabili2ing arms 22, 24 forms a stable base, and the cross-sectional diameter of the needle guide 18 is of a si2e for providing a comfortable grip (about 5mm) for the user. The guide is rigid with respect to the stabili2ing arms 22, 24, and is unable to rock off its vertical axis, or bend or twist with respect to any of the stabili2ing arms 22, 24.

The needle guide 18 contains a bore or lumen 20, which is wide enough to accommodate either a syringe 28 or just the needle 30.

Finally, the guide 18 allows the introduction of an advancing needle 30 at a pre-determined radial distance from the limbus 10, and also ensures that the needle 3Ois advanced in the correct direction with respect to the radius of the globe (i.e. eye ball). Furthermore, the apparatus 16 also stabilises the globe during injection, and helps to prevent ocular damage which could otherwise occur during the operation.

Claims

-16 -Claims 1. An apparatus for intraocular injection, the apparatus comprising needle guide means and a plurality of stabilizing arms attached thereto, wherein, in use, the stabilizing arms are adapted to be placed against the surface of an eye, and the guide means is adapted to guide a needle towards the eye.
2. An apparatus according to claim 1, wherein the apparatus comprises at least two stabilizing arms, or at least three stabilizing arms.
3. An apparatus according to either claim 1 or claim 2, wherein the needle guide means comprises a cylinder having open-ended proximal and distal ends, which are interconnected by a bore or lumen.
4. An apparatus according to claim 3, wherein the lumen of the guide means has a width which is sufficient to receive just a needle connected to a syringe.
5. An apparatus according to claim 3, wherein the lumen in the needle guide means is wide enough to accommodate a syringe and its needle coupled thereto.
6. An apparatus according to any preceding claim, wherein the needle guide means is substantially translucent.
7. An apparatus according to any one of claims 3-6, wherein a centre point of the lumen at the distal end of the guide means substantially corresponds with the position of a needle penetration point pars plana in the sclera of the eye, when the apparatus is in use.
8. An apparatus according to any preceding claim, wherein the plurality of stabilizing arms radiate transversely outwardly from a side wall of the needle guide means.
9. An apparatus according to any one of claims 3 to 8, wherein the plurality of stabilizing arms radiate transversely outwardly from at least adjacent the distal end of the needle guide means.

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10. An apparatus according to any preceding claim, wherein first and second stabilizing arms are substantially the same length as each other, and a third stabilizing arm is longer than the first and second arms.
11. An apparatus according to claim 10, wherein the angle formed between the longitudinal axes of the first and second arms is between approximately 120° and 170°.
12. An apparatus according to either claim 10 or claim 11, wherein the angle formed between the longitudinal axis of the third arm and the longitudinal axes of the first and second arms is between approximately 90° and 130°.
13. An apparatus according to any preceding claim, wherein the stabilizing arms comprise an eye bearing surface having a curved shape for matingly bearing on the outer surface of the eye.
14. An apparatus according to claim 13, wherein the arms are curved with respect to their hori2ontal plane such that they form a curved or concave lower surface.
15. An apparatus according to claim 14, wherein the curvature of the curved lower surfaces is that of a circle having a radius which is between about 9mm and 15mm.
16. An apparatus according to any one of claims 10 to 15, wherein the first and second stabilizing arms comprise an edge, which, in use, is adapted to be positioned approximately adjacent the limbus of the eye.
17. An apparatus according to any one of claims 10 to 16, wherein the two arms are curved with respect to their vertical axes.
18. An apparatus according to claim 17, wherein the curvature of the curved surface is that of a circle having a radius which is between about 4mm and 7mm.
19. An apparatus according to any one of claims 10 to 18, wherein the circumferential length of the two arms following the curvature of the limbus is between approximately 6mm and 10mm when measured from the tip of one of the arms to the tip of the other arm.

-18 -
20. An apparatus according to claim 19, wherein, when the apparatus is in position on the eye, the tip of the third arm is between approximately 8mm and 15mm away from the limbus.
21. A kit for intraocular injection, the kit comprising the apparatus according to any one of claims 1 to 20, and a syringe.
22. A kit according to claim 21, wherein the syringe is connected to the apparatus.
23. A kit according to either claim 19 or claim 20, wherein the syringe is inserted into the lumen of the needle guide means.
24. Apparatus according to any one of claims 1 to 20, or a kit according to any one of claims 21 to 23, for use in intraocular injection.
25. A method of guiding a needle into the interior of a subject's eye, the method comprising the steps of:- (i) positioning the apparatus of any one of claims 1 to 20, or the kit of any one of claims 21 to 23, on a subject's eye; and (ii) guiding a needle through the guide means until the tip of needle is positioned in the interior of the eye.
26. A method of administering, to a subject in need of treatment, a composition comprising an effective amount of a medicament for treating a condition of the subject's eye, the method comprising the steps of:- (i) positioning the apparatus of any one of claims 1 to 20, or the kit of any one of claims 21 to 23, on a subject's eye; (ii) guiding a needle coupled to a syringe containing the composition through the guide means until the tip of needle is positioned in the interior of the eye; and -19 - (iii) expelling the composition into the interior of the eye.