BACKGROUND OF THE INVENTION Wax formation occurs naturally in human ears.

Generally, this does not present any problem because normal movement of the jaw effects migration of the wax out of the ear canal. Wax does accumulate, however, in the ears of some people and this may cause problems unless the wax is removed. Such accumulation may result from a tortuous ear canal, abnormal rigidity of ear canal cartilidges, or insufficient mastication due to a patient's preference for soft foods.

Accumulation of wax in an ear may impair natural hearing or the functioning of a hearing aid. Such accumulation may also prevent adequate visualization of ear drums by medical practitioners seeking to diagnose certain conditions in the middle ear.

Other undesirable and sometimes painful consequences of undue accumulation of wax in an ear may include pain, discharge and itching.

Various methods have been used to extract accumulated wax from ears of patients. Traditionally, medical practitioners have utilise a syringe to flush an ear with warm water having a temperature approximating the body temperature. Unfortunately, this method suffers a number of disadvantages. For example, ear syringes currently available are typically bulky and heavy and are therefore generally difficult to operate. Consequently, there is a capacity for operators having unsteady hands to place a syringe nozzle too far in the ear canal which may cause damage to the ear

drum. Another problem often associated with ear syringes is that if the nozzle of a syringe is of a size sufficient to occlude the ear outlet, operation of the syringe may result in a pressure build-up within the ear canal and thereby cause rupture of the ear drum; this situation typically arises with children's ears or adult ears having narrow ear canals. Other disadvantages include (i) detachable nozzles associated with ear syringes have a propensity for detachment during operation which could perforate the ear drum, (ii) because ear syringes are typically bulky in nature, it is difficult to regulate the velocity of water expelled from the nozzle which may cause pain or damage to the ear drum, (iii) generally, the diameter of the nozzle bore associated with ear syringes is relatively wide and, in use, a correspondingly wide jet of water is expelled from the nozzle which can push a relatively large accumulation of wax further in towards, instead of away from, the ear drum, (iv) the syringe and nozzle are each required to be sterilized before use on each patient, (v) typically, a linear nozzle is coaxially attached to the syringe barrel and these features preclude clear viewing of the ear canal during syringing.

Having regard to the above, there is a need to provide an improved device for removing wax accumulation from a human ear.

OBJECT OF THE INVENTION It is therefore an object of the invention to provide a flow nozzle for removing wax accumulations from a human ear which may ameliorate at least one of the foregoing disadvantages.

It is also an object to provide a fluid transfer means inclusive of a syringe comprising such flow nozzle as well as a method of removing wax accumulations from a human ear using the flow nozzle and syringe of the invention.

SUMMARY OF THE INVENTION In one aspect of the invention, there is provided a flow nozzle usable with a fluid transfer means for removal of wax

accumulations from an auditory canal, said flow nozzle comprising a proximal portion, a distal portion, a sharp transition between the proximal portion and the distal portion, and a passageway therethrough, said sharp transition defining an included angle between the distal portion and the proximal portion such that, in operation, a line of sight substantially along the axis of the auditory canal is unimpeded by the proximal portion, the proximal portion having a free end detachably engageable with the fluid transfer means, the distal portion being adapted for insertion into the auditory canal and having a free end through which fluid is expelled from the passageway into the auditory canal in use as well as having a length being such that when the distal portion is inserted into the auditory canal, the sharp transition in combination with the proximal portion substantially prevents the free end of the distal portion from contacting an ear drum associated with the auditory canal.

The feature of the included angle being present such that in operation a line of sight substantially along the axis of the auditory canal is unimpeded by the proximal portion in advantageous because it allows ease of viewing insertion of the distal portion into the auditory canal in use. Suitably, the included angle is selected from about 100 degrees to about 170 degrees, preferably from about 110 degrees to about 160 degrees, and more preferably from about 120 degrees to about 150 degrees.

The length of the distal portion is preferably selected from about 5 mm to about 25 mm and more preferably from about 15 mm to about 20 mm.

The distal portion may comprise a continuous tubular portion having a side wall which may have any suitable transverse cross-sectional dimension allowing insertion of the distal portion into the auditory canal in use.

Suitably, the passageway at the free end of the distal

portion has a bore size selected such that in use a jet of fluid which is expelled into the auditory canal is sufficiently fine to pass between the wax accumulations and the auditory canal wall. Preferably, the bore size is selected from about 1 mm to about 3 mm, and more preferably from about 1.2 mm to about 1.7 mm.

Suitably, the free end of the distal portion is radiussed or tapered. This may be advantageous because a distal portion having a radiussed or tapered free end may be less likely to cause injury to the auditory canal in use.

The proximal portion may have any suitable length but is preferably of a length such that, when in use, the free end of the proximal portion extends adjacent to, or beyond, the pinna of an ear.

For example, the length of the proximal portion may be selected from about 20 mm to about 60 mm but is preferably selected from about 30 mm to about 45 mm.

The free end of the proximal portion is detachably engageable with the fluid transfer means and may therefore comprise a suitable male-female coupling whereby the engagement of the free end of the proximal portion with the fluid transfer means results in a seal substantially resistant to escape of fluid therefrom in use.

Preferably, the male-female coupling substantially prevents accidental detachment of the nozzle during operation. For example, the free end of the proximal portion may comprise a'female'retaining means for receiving and retaining a'male'outlet of the fluid transfer means. In this regard, the outlet may have an external thread which is complementary to an internal thread of the retaining means thereby allowing screw-type engagement therebetween. Alternatively, the retaining means may comprise a wall surrounding a central cavity and at least two retaining flanges projecting inwardly from the wall wherein at least one of the retaining flanges is resiliently deformable.

The outlet of the fluid transfer means may comprise a wall

surrounding a central cavity and at least two tabs or collars projecting outwardly from the outlet wall. Secure engagement is effected by insertion of the male outlet into the retaining means until the tabs are permitted to pass through the retaining flanges.

Any suitable type of fluid transfer means may be connected to the flow nozzle to enable a person such as a medical practitioner to remove wax accumulations from a patient's ear. For example, the free end of the proximal portion may be engaged with a conduit means (eg., a hose) in fluid communication with a reservoir of fluid. In such a case, the fluid which is preferably warm, may be delivered from the reservoir to the nozzle and outwardly therefrom by gravity flow or by use of a pump connected to the conduit means.

Alternatively, the fluid transfer means may comprise a syringe. The syringe may have any suitable fluid capacity but is preferably of a fluid capacity accommodating operation by a single hand. The fluid capacity is preferably selected from about 10 mL to about 50 mL, and more preferably from about 20 mL to about 25 mL.

Suitably, the syringe has a barrel having an outlet receivable with the free end of the proximal portion. The outlet may be coaxially disposed relative to the axis of the syringe barrel.

Alternatively, the outlet may be eccentrically disposed relative to the syringe barrel. This latter embodiment is advantageous because, in operation, it assists in providing a better line of sight for placement of the distal portion of the nozzle into the auditory canal as described hereinafter.

According to another aspect, the invention resides in a syringe for removal of wax accumulations from an auditory canal, said syringe comprising a barrel, a plunger recevable in the barrel and movable axially therealong, and a flow nozzle comprising a proximal portion, a distal portion, a sharp transition between the proximal portion and the distal portion, and a passageway therethrough, the

proximal portion being connected to an outlet of the barrel, the distal portion being adapted for insertion into the auditory canal and having a free end through which fluid is expelled from the passageway into the auditory canal in use as well as having a length being such that when the distal portion is inserted into the auditory canal, the sharp transition in combination with the proximal portion substantially prevents the free end of the distal portion from contacting an ear drum associated with the auditory canal.

The proximal portion of flow nozzle may be in releasable sealing engagement with the outlet of the barrel but is preferably integrally connected thereto.

The flow nozzle and syringe may be constructed of any suitable material. Suitably, the material can be sterilized or autoclave without damage to the material. Preferably, the material is a thermoplastics material such as polypropylene.

The invention also extends to a method for removing wax accumulations from an auditory canal utilizing the flow nozzle or syringe of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be readily understood and put into practical effect, particular preferred embodiments will now be described by way of example with reference to the accompanying drawings in which: FIG. 1 is a side plan view of one embodiment of a flow nozzle according to the present invention; FIG. 2 is a side plan view of a syringe comprising a flow nozzle integrally formed therewith; FIG. 3 is a perspective view of the syringe of FIG. 2 in operation.

DETAILED DESCRIPTION With reference to the drawings and more particularly to

FIG. 1, there is shown an embodiment of a flow nozzle in accordance with the invention. The flow nozzle shown generally at 10 comprises a proximal portion 11, a distal portion 12, a sharp transition 13 between the proximal portion 11 and the distal portion 12 and passageway 14therethrough.

The proximal portion has a free end 15 which reversibly receives and engages a barrel outlet 16 of syringe 17. Free end 15 comprises a wall 18 surrounding a central cavity 19 and two resiliently deformable retaining flanges 19A, 19B projecting inwardly from the wall 18. Outlet 16 comprises a wall 20 surrounding a central cavity 21 and two tabs 22A, 22B projecting outwardly from wall 20.

Proximal portion 11 is securely engaged with syringe 17 by insertion of outlet 16 into central cavity 19 of free end 15 until tabs 22A, 22B are permitted to pass through retaining flanges 19A, 19B.

The length A of proximal portion 11 is preferably of a length such that, when in use, the free end of the proximal portion extends adjacent to, or beyond, the pinna of an ear. In this embodiment, length A is about 38 mm.

The sharp transition 13 defines an included angle X between the axis of the distal portion 12 and the axis of the proximal portion 11. Included angle X is selected such that, in operation, a line of sight substantially normal to the auditory canal is unimpeded by proximal portion 11. This advantageously allows ease of viewing insertion of distal portion 12 into the auditory canal in use. In this embodiment, included angle X is about 145 degrees.

The distal portion 12 has a radiussed or tapered free end 23 and a continuous wall which has a transverse cross-sectional dimension allowing insertion of the distal portion 12 into the auditory canal in use. The passageway 14 at free end 23 has a bore size ( selected such that in use a jet of fluid which is expelled into the auditory canal therefrom is sufficiently fine to pass between the wax

accumulations and the auditory canal wall. In this embodiment, the bore size ¢ is about 1.5 mm.

The length B of distal portion 12 is selected such that when distal portion 12 is inserted into an auditory canal, the sharp transition 13 in combination with the proximal portion 11 substantially prevents free end 23 of distal portion 12 from contacting an ear drum associated with the auditory canal. In this embodiment, length B is about 20 mm.

Turning now to FIG. 2 there is shown a 25 mL syringe 100 constructed of a thermoplastics material such as polypropylene and comprising a barrel 101 and a plunger 102 recevable in the barrel 101 and movable axially therealong. Syringe 100 also comprises a flow nozzle 103 which is substantially similar to the flow nozzle of FIG. 1 with the exception that nozzle 103 is integrally formed with barrel 101.

Flow nozzle 103 is eccentrically disposed relative to the axis of the syringe barrel 101 and this is advantageous because, in operation, it assists in providing a better line of sight for placement of the nozzle 103 into the auditory canal as described hereinafter.

With reference to FIG. 3, there is shown a syringe 100 being used to remove wax accumulations 200 from the auditory canal 201 of a patient's ear 202. The syringe 100 is first sterilized and filled subsequently to its capacity of 25 mL with a suitable irrigant such as warm water. The operator of the syringe then carefully inserts the distal portion 12 of syringe 100 into the entrance 201 A of auditory canal 201 of ear 202. The proximal portion 11 of syringe 100 is disposed at an angle above the auditory canal 201 and extends adjacent to an upper portion 203A of pinna 203 of ear 202.

The barrel 101 of syringe 100 may abut to upper portion 203A and this acts to improve stability of the syringe 100 during operation.

Moreover, when placed against the pinna 203 in such a manner, the

structure of syringe 100 also functions to assist safe insertion of the distal portion 12 further in the auditory canal 201. In this regard, the sharp transition 13 spaces the proximal portion 11 away from a line of sight Z substantially coaxial with the axis of the auditory canal 201. The proximal portion 11 is eccentrically disposed relative to the axis of the syringe barrel 101 and this also serves to space the syringe away from the line of sight Z in use.

After placing the distal portion 12 into entrance 201 A, the operator having a line of sight Z inserts the distal portion 12 further in the auditory canal 201 preferably between the wax accumulations 200 and the auditory canal wall 204. The free end 23 of distal portion 12 is substantially prevented from being inserted beyond a minimum safe distance away from ear drum 205 of ear 202 because, further insertion of distal portion 12 will cause sharp transition 13 and proximal portion 11 to rest against outer portion 204B of auditory canal wall 204.

When distal portion 12 is in position, the operator presses plunger 102 of syringe 100 to gently expel a fine jet 206 of warm water between wax accumulation 200 and auditory canal wall 204 towards ear drum 205. The jet 206 strikes ear drum 205 and subsequently rebounds therefrom into wax accumulation 200. The operator continues pressing against plunger 102 until wax accumulation 200 is expelled from the auditory canal 201.

It should be noted that a fine jet is preferable because otherwise, if there is insufficient space between the auditory canal wall 204 and the wax accumulations (especially if such wax accumulations are relatively large), the jet will drive such wax accumulations further in towards the ear drum 205. As described above, the fine jet 206 is achieved by passageway 14 at free end 23 of distal portion 12 having a relatively small bore size 4).

Compared to ear syringes currently available, the flow nozzle and syringe of the invention facilitate easier and safer removal of wax accumulations from a human ear.