The present invention relates to a surgical injector system, more particularly, to injectors with lens cases for non-preloaded as well as for preloaded intraocular lenses (IOLs) and methods for operation thereof.
An IOL is an artificial lens implanted in the eye, for example, as a replacement for the natural crystalline lens after cataract surgery or to alter the optical properties of an eye in which the natural lens remains. IOLs include an optic, and preferably at least one flexible fixation member or haptic which extends from the optic and becomes affixed in the eye to secure the lens in position. The optic normally includes an optically clear lens. Implantation of such IOLs into the eye involves making an incision in the eye. It is advantageous, to reduce trauma and accelerate healing, to have an incision size as small as possible. Modern IOLs are foldable so that the IOL can be inserted through a smaller incision into the eye. A variety of instruments have been proposed to aid in inserting such a foldable lens in the eye.
In the beginning the surgeon simply used surgical forceps having opposing blades which were used to grasp the folded IOL and insert it through the incision into the eye. While this method is practically not in use anymore, most surgeons are using more or less sophisticated IOL injectors offering more control to the surgeon when inserting the IOL into the eye. IOL injectors have recently been developed with reduced diameter nozzles which allow for a much smaller incision to be made in the cornea than is possible using forceps only. Smaller incision sizes (e. g., less than about 3 mm) are preferred over larger incisions (e.g., about 3.2 to 5+mm) since smaller incisions have been attributed to reduced post-surgical healing time and complications such as induced astigmatism.
Since IOLs are very small and delicate articles of manufacture, great care must be taken in their handling. In order for the IOL to fit through the smaller incisions, they need to be folded and/or compressed prior to entering the eye wherein they will assume their original unfolded/uncompressed shape. The IOL injector device must therefore be designed in such a way as to permit the easy passage of the IOL through the device and into the eye, yet at the same time not damage the delicate IOL in any way. Should the IOL be damaged during delivery into the eye, the surgeon will most likely need to extract the damaged IOL from the eye and replace it with a new IOL, a highly undesirable surgical outcome.
Several types of injector systems are available today and can be clearly distinguished and separated regarding the loading of the IOL. There are mainly two types of non-preloaded injector systems: Most common are the winglet type cartridge injectors where the unfolded IOL has to be loaded from the side, being prefolded by the closing winglets and then pushed forward through the cartridge nozzle by a plunger with a tip made from a soft material. This generic type of non-preloaded injector is the most universal type, usable for many kind of IOLs.
Disadvantage of injectors with non-preloaded winglet-type cartridge is the need to insert the IOL into the winglets by forceps requiring skill and experience of the user in order to avoid the risk of mishandling and/or damaging the lens during loading and closing the cartridge.
The other type of non-preloaded injector system has a fix-type cartridge that has to be loaded by the unfolded IOL from the back, where the lens is folded simply by being pushed through a narrowing cartridge nozzle by a pushing rod from hard material. These injector systems usually work only with hydrophobic IOLs and due to the lack of pre-folding of the IOL, the size of the nozzle tubes is larger. Patent specification WO1994007436 describes a non-preloaded winglet-type injector system with a pushing rod for hydrophobic IOLs
Besides the non-preloaded injector systems there are different so-called preloaded injector systems. In case of some preloaded injector systems the hydrophobic IOL is placed into the injector during the assembly process of the injector and the IOL and the injector are packed, sterilized, stored and shipped together. These are the single-phase, truly preloaded IOL/injector systems.
Patent specifications U.S. Pat. No. 7,156,854 and WO2007080869 both describe such a single-phase, preloaded injector system with a hard pushing rod for hydrophobic IOLs.
In case of hydrophilic preloaded IOL/injector systems the IOL is usually preloaded in a special lens case or container, packed, sterilized, stored and shipped separately from the injector. The reason for this is the different sterilization process needed for the dry-packed injector (ethylenoxide) and for the hydrated IOL (steam). Before injection the lens case/cartridge with the preloaded hydrophilic IOL has to be put on the injector, thus creating one injection system with a preloaded IOL. Some of these systems are winglet type, some of them backloaded type injectors.
Patent specification WO2007027499 describes an injector system for hydrophilic IOLs, enabling the user to load the IOL into the injector system without touching the IOL.
Patent specification WO2007078602 illustrates a folding arrangement for non-preloaded injectors in which small sized hydrophilic IOLs can be folded prior to injection by a rotational movement. However, the IOL is primarily stored in a vial before it has to be loaded into the cartridge.
Both arrangements are suitable for hydrophilic IOLs only and can be ruled out for hydrophobic IOLs.
Looking at these different kinds of injector systems, all of them with their own limitations, our target with this invention is to create a universal intraocular lens injector system that can be used as a preloaded or non-preloaded system, for hydrophobic or hydrophilic lenses. In all cases we want to use the same basic injector setup with the same type of cartridge suitable for safely loading and injecting preloaded and non-preloaded IOLs, from hydrophobic or hydrophilic materials.
We realized that combining the winglet-type cartridge with a controlled loading mechanism in a single device can result in an advantageous construction suitable for both non-preloaded and preloaded IOLs. This combination can be carried out by separating the levels of loading and injection planes.
In case of non-preloaded IOLs, i.e. when the injector and the IOL are shipped separately, this injector system is suitable for most types of foldable IOLs, both hydrophilic and hydrophobic. Its lens case allows a very simple and safe loading of the unfolded IOL minimizing the risk of any mishandling or damage of the IOL.
This injector system is also capable of receiving a closed lens case preloaded with a IOL, thus it is a 2-phase preloaded injection system for preloaded IOLs.
Finally, with the help of a modified lens case pre-assembled with the injector it can function as a single-phase preloaded IOL/injection system for hydrophobic IOLs.
In all cases the key element of the injector is the cartridge providing two different levels (i.e. planes) for the IOL. The loading of the IOL is carried out in the open position of the cartridge at an upper plane, i.e. at the level of the loading plane. During closing the cartridge, two operations are performed at the same time: on one hand the IOL is pre-folded and on the other hand the pre-folded IOL descends from the upper loading level to a lower injection level, which is aligned with the axis of the injection plunger.
The other key element of the invention is a lens case, sitting behind the cartridge, from where the loading of the IOL into the cartridge can be carried out. This lens case has different versions. One version that can be opened is sitting fixed behind the cartridge and has to be loaded with a non-preloaded IOL. Another version of this lens case is preloaded, separately sterilized and packed with a IOL and can be mounted in a single movement on the injector behind the cartridge. A third version of the lens case for preloaded hydrophobic IOLs is pre-mounted on the injector, having two positions: an upper storage/shipping position (i.e. level) and a lower loading position (i.e. level) where the lower loading level of the lens case is aligned with the upper loading level of the cartridge mentioned above. Such a lifting lens case is mounted on the injector in the upper position providing safe storage/shipping function. During the usage, the lifting lens case is moved to the lower position, to the loading level. This version of the lens case in cofunction with the cartridge creates three different functional levels (i.e. planes) for the IOL in the injector: a storage/shipping level, a loading level and an injection level.
Accordingly, the invention relates to an injector system for injecting foldable IOLs. The injector system comprises a cartridge with a nozzle tube, a lens case, an injector body, an injection plunger and a loading pusher. The injector body accommodates the loading pusher and the injection plunger the axis of which are parallel to each other and are accommodated in the injector body on a level of loading and on a level of injection, respectively. The cartridge comprises two winglets connected to each other by a hinge joint providing an open and a close position for the cartridge. In the open position of the cartridge, the inner surface of the winglets forms an inner space on the level of the loading plane, where the plane of the inner space is aligned (coincides) with the axis of the loading pusher. In the closed position of the cartridge, the inner surface of the winglets forms an inner space on the lower level of the injection axis, where the axis of the inner space coincides with the axis of the injection plunger. The lens case is attached to the injector body behind the cartridge. The inner surface of the lens case forms an inner space for the unfolded IOL.
In an advantageous embodiment, the lens case attached to the injector body has an upper position where the plane of the inner space of the lens case is above the level of loading, and a lower position where the plane of the inner space of the lens case is on the level of the loading plane, where the longitudinal axis of the inner space coincides with the axis of the loading pusher. In other words, in the embodiment for such a lifting lens case three levels are defined for the IOL in this embodiment: 1.) storage and shipping the IOL in the upper position of the lens case, 2.) loading of the IOL in the lower position of the lens case that is on the level of the loading plane and 3.) the level of the injection axis.
The invention also relates to a method of operating the injector. Three methods are developed, one for non-preloaded IOLs, one for IOLs preloaded in a separate lens case and one for hydrophobic preloaded IOL.
In case of injecting a non-preloaded IOL, the method comprises the steps of a.) injecting visco-elastic material into the open cartridge and into the open lens case; b.) placing the IOL into the lens case; c.) closing the lens case; d.) moving the IOL into the cartridge by pushing forward the loading pusher; e.) pulling back the loading pusher; f.) closing the cartridge; g.) injecting the IOL by pushing forward the injection plunger.
In case of injecting an IOL preloaded in a separate lens case, the method comprises the steps of a.) mounting the lens case preloaded with an IOL; b.) injecting visco-elastic material into the open cartridge and into the lens case through a hole; c.) moving the IOL into the cartridge by pushing forward the loading pusher; d.) pulling back the loading pusher; e.) closing the cartridge; f.) injecting the IOL by pushing forward the injection plunger.
In case of injecting a hydrophobic preloaded IOL, the method comprises the steps of a.) moving the lifting lens case from an upper position to a lower position and injecting visco-elastic material to the open cartridge and into the lens case through a hole; b.) moving the IOL into the cartridge by pushing forward the loading pusher; c.) pulling back the loading pusher; d.) closing the cartridge; e.) injecting the IOL by pushing forward the injection plunger.
This construction allows the IOL to be loaded, folded and injected by the injector in a safe way preventing mishandling and damage of the IOL.
For a more complete understanding of the invention, reference is made to the following detailed description of an embodiment taken in conjunction with the accompanying drawings wherein:
In the following, for purpose of explanation and not limitation, specific details of an injector for IOLs are set forth, in order to provide a thorough understanding of the present invention. It will be apparent to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details.
Embodiment of Injector for Non-Preloaded IOL
Embodiment of an Injector for Hydrophobic Preloaded IOLs
In order to keep the IOL 1 in the lens case 6 during storage and shipment but let it loaded to the cartridge 5 before the usage, two gates 10 are provided on the injector body 2 at the both ends of the lens case 6 closing the both end of the inner space of the lens case 6 in its upper position as it is shown in
When the lens case 6 is moved to the lower position, as it is depicted in the sectional view of
Embodiment of an Injector for Hydrophilic or Hydrophobic IOLs Preloaded in a Separate Lens Case
In
Embodiment Details of the Cartridge for Non-Preloaded as Well as for Preloaded IOL
In order to have a safe close position of the cartridge 5, the inner surface of one of the winglets 13 at its upper part can be provided with a rim 24 fitting to a groove 25 of the other winglet 12 at their upper part.
In and advantageous embodiment, the bottom parts of the winglets 12, 13 are provided with legs 29, 30 seating in the plane of the injection plunger 4 when the cartridge 5 is in open position. Legs 29, 30 getting contact to each other in the open position of the cartridge 5 prevent casual injection by blocking the injection plunger to move forward to the cartridge 5 as well as act as limiters for the winglets 12, 13 in the open position.
Operating Injectors for Non-Preloaded and Preloaded IOLs
In the next figures, the operating steps for non-preloaded and preloaded IOLs are described simultaneously in order to highlight the difference between the two methods.
In
The same operation is carried out for the hydrophobic preloaded IOL 1 according to
After the loading step, the loading pusher 3 is pulled back in case of non-preloaded as well as in preloaded IOL as it is shown in
Reaching the injection level 17, the injection plunger 4 is pushed forward, injecting the IOL 1 to the patient eye. This step is also identical both for non-preloaded IOL as shown in
In case of injecting a hydrophilic or hydrophobic IOL preloaded in a separate lens case 1, the method comprises the steps of a.) mounting the lens case 6 preloaded with a hydrophilic or hydrophobic IOL 1; b.) injecting visco-elastic material into the open cartridge 5 and into the lens case 6 through a hole 33; c.) moving the IOL 1 into the cartridge 5 by pushing forward the loading pusher 3; d.) pulling back the loading pusher 3; e.) closing the cartridge 5; f.) injecting the IOL 1 by pushing forward the injection plunger 4.
Although three preferred embodiments of the present invention have been illustrated in the accompanying drawings and described in the foregoing detailed description, it is understood that the invention is not limited to the disclosed embodiment but is capable of numerous rearrangements, modifications, and substitutions, i.e. swop of recesses and protrusions on some parts of the injector without departing from the invention.
Filing Document | Filing Date | Country | Kind |
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PCT/HU2017/000053 | 12/28/2017 | WO | 00 |