a new instrument for micro-aspiration/ infusion during ex tracapsular surgery J.G .F. Worst, M.D . Haren, Holland G. Vijfwinkel Rotterdam, Holland
The standard procedure for extracapsular cataract extraction requires a large incision, extensive opening of the anterior capsule, expression of the nucleus and removal of cortical lens remnants. Complete removal of cortical lens remnants is necessary to prevent reformation of cellular matter
on the posterior capsule. We have used push/ pull aspiration of peripheral lens matter by a method of simple syringe infusion and aspiration with gentle oscillation of the syringe handle. Though quite satisfactory, this requires considerable manual skill. A safer method could be provided by an instrument with considerable aspiration force but small volume. This paper reports on the development of such an aspiration/ infusion tool· for use with peripheral lens matter. INSTRUMENT DESIGN Through the hollow handle of the instrument a thin-walled flexible cannula is connected to the injection/ aspiration cannula (Fig. 1). At the lower part of the handle a window gives access to the inner
Fig. 1(Worst and Vijfwinkel). Micro·aspiration/ infusion tool with manually compressible compartment near tip.
·Available from Medical Workshop, Groningen, Holland AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JANUARY 1979
59
tubing for the forefinger of the surgeon. At the other end is a cogwheel which can be rolled along a slot to close the tube either partially or completely, or to open it completely (three positions). At the end of the handle the internal cannula has been connected to an outside cannula, which in turn can be connected to a syringe or an infusion bottle.
position (tube partially closed) will allow low-speed fluid infusion.
SURGICAL TECHNIQUE During extracapsular surgery, all air is rinsed out of the system by initiating a fluid flow with the syringe or the intravenous drip bottle. After partial closure of the anterior chamber with one or two sutures, our aspiration/infusion instrument is used to inflate the anterior chamber and create an eddying current for expulsion of loose lens particles. Use of this system in a semiclosed or smallincision type of cataract wound introduces the risk of posterior capsule rupture from overfilling of the anterior chamber. To have free outflow of irrigation fluid, care must be taken to leave a sufficient degree of the corneoscleral wound unsutured. The infusion flow is maintained either by an intravenous drip system or by a constant flow through the syringe. If filters are used with the drip system, it may be necessary to hang the infusion bottle above normal intravenous infusion height or to pressurize the bottle with an air injection. The aspirationlinfusion instrument is held in the right hand of a right-handed surgeon. The left hand then moves the cogwheel to completely block further fluid entry. Once the system is thus closed, repeated compression and release of the front part of the tube (under the forefinger) administers a push/pull force which pries lens fibers from the peripheral lens capsule and from the capsule fornix. Slight pull may also be exerted while this maneuver is executed. The volume of the closed tube system is insufficient to empty the anterior chamber when the tube is released. However, though aspiration volume is insufficient to break the capsule, the small volume changes still exert considerable force. Care must be taken not to aspirate in the pupillary area, as the capsule here is more flaccid and can more easily be aspirated and torn. After several compression/release movements with the index finger, the system is reopened for infusion. This cycle must be repeated all along the circumference of the lens capsule for effective evacuation of the capsular bag and a "vacuum-cleaning" effect on germinal lens fiber cells. When the cogwheel is used to start and stop infusion from an infusion bottle, the intermediate 60
AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JANUARY 1979
The standard procedure for extracapsular cataract extraction requires a large incision, extensive opening of the anterior capsule, expression of the nucleus and removal of cortical lens remnants. Complete removal of cortical lens remnants is necessary to prevent reformation of cellular matter
on the posterior capsule. We have used push/ pull aspiration of peripheral lens matter by a method of simple syringe infusion and aspiration with gentle oscillation of the syringe handle. Though quite satisfactory, this requires considerable manual skill. A safer method could be provided by an instrument with considerable aspiration force but small volume. This paper reports on the development of such an aspiration/ infusion tool· for use with peripheral lens matter. INSTRUMENT DESIGN Through the hollow handle of the instrument a thin-walled flexible cannula is connected to the injection/ aspiration cannula (Fig. 1). At the lower part of the handle a window gives access to the inner
Fig. 1(Worst and Vijfwinkel). Micro·aspiration/ infusion tool with manually compressible compartment near tip.
·Available from Medical Workshop, Groningen, Holland AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JANUARY 1979
59
tubing for the forefinger of the surgeon. At the other end is a cogwheel which can be rolled along a slot to close the tube either partially or completely, or to open it completely (three positions). At the end of the handle the internal cannula has been connected to an outside cannula, which in turn can be connected to a syringe or an infusion bottle.
position (tube partially closed) will allow low-speed fluid infusion.
SURGICAL TECHNIQUE During extracapsular surgery, all air is rinsed out of the system by initiating a fluid flow with the syringe or the intravenous drip bottle. After partial closure of the anterior chamber with one or two sutures, our aspiration/infusion instrument is used to inflate the anterior chamber and create an eddying current for expulsion of loose lens particles. Use of this system in a semiclosed or smallincision type of cataract wound introduces the risk of posterior capsule rupture from overfilling of the anterior chamber. To have free outflow of irrigation fluid, care must be taken to leave a sufficient degree of the corneoscleral wound unsutured. The infusion flow is maintained either by an intravenous drip system or by a constant flow through the syringe. If filters are used with the drip system, it may be necessary to hang the infusion bottle above normal intravenous infusion height or to pressurize the bottle with an air injection. The aspirationlinfusion instrument is held in the right hand of a right-handed surgeon. The left hand then moves the cogwheel to completely block further fluid entry. Once the system is thus closed, repeated compression and release of the front part of the tube (under the forefinger) administers a push/pull force which pries lens fibers from the peripheral lens capsule and from the capsule fornix. Slight pull may also be exerted while this maneuver is executed. The volume of the closed tube system is insufficient to empty the anterior chamber when the tube is released. However, though aspiration volume is insufficient to break the capsule, the small volume changes still exert considerable force. Care must be taken not to aspirate in the pupillary area, as the capsule here is more flaccid and can more easily be aspirated and torn. After several compression/release movements with the index finger, the system is reopened for infusion. This cycle must be repeated all along the circumference of the lens capsule for effective evacuation of the capsular bag and a "vacuum-cleaning" effect on germinal lens fiber cells. When the cogwheel is used to start and stop infusion from an infusion bottle, the intermediate 60
AM INTRA-OCULAR IMPLANT SOC J-VOL. V, JANUARY 1979
