GB2222952A - Ophthalmologlcal device - Google Patents

Description

OPHTHAWOLOGICAI, DEVICE 2r 22 2 9.1_5 2 The invention relates generally to

medical equipment and more specifically to ophthalmological devices.

The invention is applicable for removal of vitreous humor,, soft cataracts, preretinal membranes, and other pathologically affected intraocular structures, as well as foreign bodies.

Over tiae past few years widespread use has been gained in opLthalmosurgery by surgical instruments for carrying out intraocular surgery through a small (under 1.5 mm) incision in the ocular wall.

One state-of-the-art opiathalmolo6ical instrument is known, which is in faqt a cutting instrument executin6 reciprocation motion and haviae, a caanr.'iel for the vitreous humor to aspirate. liae cutting knife of the instrument skiaped as a nollow tube r%-,ceives reciprocating motion from an electric motor accommodated in the instrument Grip. Tne knife is coaxially mounted in the outer tube having one closed end to form a working endpiece together therewith, an opening being provided in the side wall of the outer tube close to its end (US, A, 41108,182).' TLe intraocular tissue to be removed is sucked into the interior space of the ouzer tube by virtue o.f a ne;ative pressure built up in the hollow inner tube and imparted through its open end to the open- ing in the outer tube. Wnen extended the knife pointed end, while closing the opening in tae outer tube, cuts off the tissue located inside the tube, whereupon the cut-off tissue is removed from the eye by aspiration. Then the knife returns into the initial positions thus exposing the opening in the outer tube, and the wiiole operating cycle is repeated.

However, the fact that the dr-ve is accommodated I 'V L in the inst-rumant il-and-rip adds to its vieieht and caus- es pa-r-as-Ltic vijrations o.1. the working endpiece.-Be- sides, provision of an electric motor in the instru ment makes sterilization difficult. The instrument -ruction makes no provision for adjustinE the work c o ns -W ing stroke and the force a:-iplied to bioloSical tissues.

One prior-art ophttialmological instrument fea tures its -0orkinE; endpiece made up ol' two tubes in a manner described above I wnile a drive waic" is in fact an electromagnets is brou,.,ht outside the handgrip and is associated with the endpiece tnrou;L a flexible tie-rod enclosed in a sheath (SU, A, 980,710). However, the aforesaid instrument is very sensitive to flexures of tae flexible tie-rod whica are inevitable in the course of surgery. Suci sensitivity is caus-e-tive of high ly undesirable variations of the working endpiece stroke amplitude. In addition$ bad vibrations are imparted to ti,e wurkin8 endpiece due to electromagnet kicks.

One more ophthalmological device known in the present state of the art is adopted as the prototype; it comprises a cuttin.---instrument in the form of a working endpiece whica incorporates a stationary fixed outer tube havin.---. a closed free end and a side hole nearby c said eadg and an inner tube, whica is in fact a movable element of the cutting instrumenty having a pointed free 0 end and being capable of reciprocating motion. The working endpiece may be made as microscissors. The device cou.prises also a hand-grip on vinich is fixed the work- in6. endpiece and which accommodates a part of the drive made as a bellows mecLanically associated with the movable element and connected to the flexible tube.

The drive is in fact a pneumatic system consisting, o2 a compressor, control members of said compress- or, and a flexible tube whose one end coLimunicate! witi-A the compressor and the otlier end, witlia the bellows accominouated in the 12.andt,--- rip (US, Ay 3j884238).

Since the endpiece is introduced directly into the operative field tne output power o_--- the pneumatic drive is limited, whereby the drive fails to provide an adequate force applied to the movable element,,iaich is required, in particular, for cut- uin; through dense intraocular tissues, e.g., the pupillary membranes, fibrous vitreous adhesions, and some other similar tis- sues. Bebides, such a drive is unadaptable to ade quately reliable forceps for gripping foreign bodies or membranous cataracts. Attempts aimed at increasing the drive power by elevatin,6 air pressure in the pnea- matic drive are fraught with a danger of air inrush into the operative field. Lloreover, the operating chain control pedal - electric control circuit - compressor valving system - po-wer fluid (air being known as highly compressible working fluid) - bellows - working endpiece rwovable element' features but inadequately quick action. This in turn results in that surgeon's decisions are execuUi-ed witn some delay in the course of surgery.

The surgeon is rather inflexibly bound to the mode of- the device operation, since the operating modes are chaa,,ed on the control panel, which involves the presence of a techr-lically skilful operator in the operatin, room.

The scope off the disadvantages mentioned above results in that tde surbeon 11-s but an inadequate direct control over the operation of tile device, i.e., lie has ly upori such factors as reliability and operating to re.L capabilities of a complicated electromechanical arrange ment, promptness and adequate comprehension of auxiliary attending personnel, stable operation of power mains, and some other, which are far from ensuring exact and instantaneous execution of surgeon's decisions. In its turn an inadequate direct surgeon's control over tkie operation of the instrument leads to affected safe ty of intraocular surgery and lower efficacy thereof in cases where surgeocils decisions fail to be executed in a full scope due to its going beyond the limits of the instrument capabilities.

1 0 25, It is an object of the invention to provide an ophthalmological device wuici'.L enables the surgeon to effect a direct control over the motion amplitude and the force of the movable element.

the invention to provide It is another object of n 1 viould not require higher reliability of the drive w,,ic,.L readjustment in tne course of surgery.

It is still another object of the invention to reduce the amount of the attending personnel.

It is yet still another object of the invention to dec-ease tne overall dimensions of the device so as to render it Portable.

It is likewide an object of the invention to provide a possibility of adjustinF. the:i.,otion amplitude anu/or force of tae movable elerieit iw...ed.-Latvely in the course of' the working c-,;cle of sur6 ery performed.

It is one more object o.L the invention to J provide quick replacement of the surgical instrument.

The foregoing and other objects and advantageous features of the present invention are accomplished due to the fact that an ophthalmolo6ical device, ac cording to the invention, comprises a surgical instru ment introducible into the eye caamoer of a patient and -0 two coaxial mutually movable elements of made up o.L;hicii one fixed stationary and coupled to a housing, while the other element is movable and connected to a drive which is in fact a closed hydraulic system effecting mutual displacement of the surgical instrument elements and has a pressure-exerting contrivance.

Such an embodiment of the drive of the proposed ophthalmological device enables the surgeon to effect a direct control over the motion amplitude of the mov able elemept and the force applied thereto.

It is expedient that the closed hydraulic system of the proposed ophthalmological devicey comprising a drive with one bellows connected to the movable ele ment, snould cor:iprise a second bellows accommodated in the pressure-exerting contrivance, while the first bellows connected to the surgical instrument movable elem--.,-i'kj, be acconl,"lodated inside the housing.

The end of tile movable element extending from the stationary fixed eleweat may rest upon the end of the bellows acconi;.,odated inside trie housing.

It is advisable ti-Lat tile movable element be.

sPrine,-loaded with respect to tne bellows accommodated insiUe the housing, by means of a spring fitted onto the movable element.

It is convenient that the second bellows be in terposed between two surfaces that form the pressure exertiti6 contrivance which is in fact a pedal.

Lle surgicaL instrument can be made detachable, while the bellows end against which the movable ele' ri ment butts up serves as a pa-rtin,face, ana forceps 2.5 C1 or scissors can be made use of as the detachable sur g-ical instrument.

When both o_f the stationary and movable elements are suaped as tubes of wLicia the inner one has a connector for removing various tissues from a patient's eye, said connector being located on the extending end off the movable element, in the ophthalmological de- vice, accord.-'Ln6 to tue invention, the spring fitted on the movable element may have a stop the function of whicii is performed b5r the connector.

Further objects and advantages of the present inv--ntion jill become obvious from a consideration of some specific exemplary embodiments thereof to be read;itt reference to the accompanying drawings:

FIG. 1 is a General diagraumatic view of an opht"almolo6ical device, accordin., to the invention; FIG. 2 is a loncitudinal sectional view of a surgical instrument vLiofi is in fact a vitreotome; FIG. 3 is a lonSitudinal sectional view of a hand- t 6rip o Uhe device, according to the invention; FIG. 4 is a general view of the liandgrip of FIG. 3; 20 FIG. 5 is a longitudinal sectional view of a surgical instrument made as forceps, according to the invention; and FIG. 6 is a longitudinal sectional view of a surgical instrument made as scissors. TLe opathalmolo6ical device of the present invention com,---rises a surgical instrument 1 (FIG.1) and a drive in the form of a closed hydraulic system. The surgical instrument 1 is made up of two mutually displaceable elements 2 (PIGS 2P 3) and 3. The element 2 is fixed stationary and connected to a housing 4. The element 3 is movable and connected to the drive which imparts mutual motion to the elements 2 5 and 3.

T he closed hydraulic system com.,rises a bellows 5 (PIGS. 1, 3) accommodated insi de the housing 4 and adjacent to an end 6 of the element 3, and a bellows 7 accommodated in a pressure-exerting contrivance. The element 3 is loaded by a spring 8 (FIG. 3) with respect to the bellows 5, said spring being fitted on the element 3 inside tne body 4.

The elements 2 and 3 (PIGS 2l 3) are shaped as tubes, and the element 3 has a connector 9 for remov- ia6 resected tissues from the patient's eye. The connector 9 is located on a portion of the element 3 i.ihic.Li extends from the element 2 and is adapted to serve as a stop for tile spring 8.

The coanector 9 (FIG. 1) communicates with an aspirator arrangement 11 through a flexible piping 10.

The closed hydraulic system is established by the bellows 5, the bellows 7, and a flexible piping 12 intercom:.unicating both bellows; the h-,sdraulic system is filled with a liquid medium, e.g., a mineral oil.

Tue pressure-exerting contrivance is essentially a pedal 13 def ined by surfaces 14 and 15, the bellows 7 being interposed therebetween. A cramp 16 is held to the surface 15 to set the surface 15 in either of the positions, viz., a working position 151 and the transfer position 15.

An elastic'sleeve 17 is provided on the piping 12 to prevent it from falling out of the pedal 13 and be5 ing jammed by tUe working surfaces 14, 15 of the pedal 13. The surface 15 aas a pivot pin 18 to rotate thereabout.

The movable element 3 (FIG. 2) has a travel res trict-or is in fact a shoulder 19 in the element 3 itself and a shoulder 20 in the stationary element 2, botia s.11oulders interacting when the elements 2 and 3 move relative to each other.

The element 2 has a lug 21 adapted to en6a6e a slot 22 (FIG. 4) to prevent the element 2 from rota- tion.

FIG. 2 illustrates trLe sur6ical instrument in the form of a vitreotome which has a closed end 23 of the element 2 and a side opening 24 with a cutting edge 27, while the element 3 has an open end 26 ith a cutting edge 27. A recess 28 is made in the side wall of the element 3 close to the end 26 to exert a holddown force oa tLe cutting ed6;es 25 and 27.

A second end 29 (FIG. 3) of the bellows 5 rests upon a nut 30 which is traversable to set a required motion amplitude of the element 3.

The slot 22 (FIG. 4) is helically shaped and is adapted for the counector 9 to move therealong.

The element 2 is locked on the iiousing 4 by means of a nut 31 (PIGS 3, 4).

The surgical instrument 1 is made detachable. an end 32 (FIG. 3) of the bellows 5 serving a parting fa- ce FIG. 5 presents an alternative embodiment of the surgical instrumentg viz., in the form of forceps 33.

which has jaws 34 and 35 connected to the movable ele ment 3 and the stationary element 2, respectively.

The surgical instrument in the form of scissors 36 (FIG. 6) having blades 37. 38 is of a similar con struction.

The ophthalmological device operates as follows.

The instrument 1 is inserted into the patient's eyeball. The surgeon holds the instrument 1 by its hous- ing 4 and brings the free end of the instrument 1 to that portion of the intraocular tissue which is to be resected. Then a negative pressure is admitted to pass through the connector 9 into the interior of the elements 2 and 3 to establish a vacuum therein, with the result that the intraocular tissues located nearby the side opening 24 of the element 2 are sucked into the Irtterlor space of the element 2 by virtue of the above vacuum..

Then the surgeon presses against the surface 15 of the pedal 13. using his foot. thus compressing the bellows 7. Since the liquid filling the hydraulic system is practically incompressible. the bellows 5 is made to elongate accordingly, thus pushing forward the movable element 3 of the instrument 1. While mov- 1 ing the element 3 interacts by its end 26 having the cutting edge 27, with the cuttin,,, ed6e 25 of the side opening 24, taus cutting off the portion of the intraocular tissues that has been sucked into the interior of the element 2, whereupon the thus-resected tissue portion is removed through the connector 9 and the pip ing 10 into the aspirator arran6ement 11. Next the sur - the 1Dedal 131 and the element 3 geon ceases depressin.' and the entire hydraulic systew are made to return into tae initial pos-ii.-tu-ion under the action of the spring 8 and by virtue- o.-jl elastic forces of the oellows 5 and 7.

Thereupon at surGeon's dise..etion tue working cycle may be repeated as many times as required at any frequeucy and force apPlied. Whenever necessary the sur6eon may hold the entire h.,,draulic sjstem and hence the element 3 in an extended position, taus closing trie side opening 24 in the element 2.

With the indtrumen-iu- 1 made as the scissors 36 or 'Llhe forceps 33 its operation proceeds practically in a similar way, witj.-L the sole exceptijri that the movable jaw 34 or the movable blade 37 moves along with the element 3.

The present device has been tested experimental- ly on ten isolated cadaveric eyes and tde eyes of four test rabbits. After successful trialling the device has been a.1, p lied clinically durinc, 32 surGical procedures in patients with various intraocular patnolo- gies. A total of 12 surgical procedures have been performed transciliary vitrectomy for unresolvable vitreal hemorrhages and opacity of the vitreous humor, 13 procedures of posterior lensectomy for solft and membranous cataracts of various etiologyq and 7 surgeries of phakovitrectomy for penetrating wounds and complicated cataract extractions followed by the formation of a vitreocortical mixture. Four of the surgeries mentioned above have been performed outside the principal clinical base in the course of emergency calls to other medical institutions. There have been employed all the three embodiments of the instrument 1, i.e., Suillotine-type vitreotome, scissors, and tubular forceps. In all cases the aesired anatomical effect has been at- tained.

Application of the proposed ophthalmological device offers the following advantages.

The surgeon can easily change the general operational disposal and tactics in the course of surgery, de- pending on a given situation or, conversely make no changes in the adopted disposal despite unforeseen cir- tances, that is, when coarse fibrous adhesions and cumst membranes are encountered the surgeon can increase considerably the force applied to the movable element"3 25 of t.2e instrument 1; when a danger of intraoperative hypotony threatens, the surgeon can change arbitrarily the opening and closing time ratio of the side openin,; in the stationary element 2 within the working - 13 cycle; or to slow down the motion of the element 3 when manipulating close to the retina, thus reducing the tractive effect on the retina.

The surgeon is enabled to grip the tissue operated upon by a preadjusted force with the use of the surgical instruinent 1 having the cutting edge 25 (27). to pull the gripped tissue portion to a required position (e.g., to retract a fibrous membrane from the retina) for its safe resection by further pressing against the pedal 13. In addition, the surgeon is in a position of catching with the forceps 33 any foreign bodies exertJng different forces thereon, which is important for catddag brittle foreign bodies. The surgeon may keep the side opening in the element 2 closed, which-is important for maintaining a balance between the fluid outflow from the eye and its inflow thereinto through an additional instrument. Whenever necessary the surgeon may replace the instrument 1 rapidly, i.e., the vitreotome for the scissors 36 or the tubular forceps, or vice versa. High operational response of the hydraulic drive of the instrument 1 enables the surgeon to respond to any change in the intraocular situation at a high rate. All features mentioned above add considerably to the efficacy of a surgical intervention, since enable the surgeon to attain practically in all cases the anatomical tasks set before surgery.

There is eliminated any risk of undue or inaccurate execution of a surgeon's command by an attendant which is authorized to change, if necessary. the operational mode of the instrument 1 on the control panel (omitted in the Drawing).

There is minimized tile risk of failure of the instrument 1 in the course of surgery, since the device is devoid of a complicated electric circuitry and a pneumatic valving system. Besides. the device is indep--. yidei-.Lt of pov,,er inains in which unforeseen failures are also possible. All these factors ado to the safety of 10 a surgical procedure.

The construction of the device is also free from such bulky units as Povier plant and control panel, which makes it possible to reduce the overall dimensions o the 4 to such an exten4- that it becomes rstrumen't, h practically a pocket-type. Compact construction arrangement of the Instrument extends considerably the scope of its practical uses and renders it very valuable for urgent surgery in emergency cases.

C:> u WHAT VY1 GLAI'mi IS 1. An ophthalmological device, comprising a surgical instrument introducible into patient's ocular chamber and made up of two coaxial mutually movable elements of which one is stationary fixed and coupled to a housini;, while the other element is movable and connected to a drive which is essentially a closed ilydraulic system adapted to effect mutual displacement of the sur- gical instrument elements and has a pressure exerting contrivance.

Claims (1)

1. 2. An ophthalmological device as claimed in Claim wherein the closed

   hyoraulic systen, comprises two bellows of i,,jhich one is accommodated iliside the hous- and is intercow ected imlith the movable element of the surgical instrument, v..,tlile the other ballovis is located in the pressure-exerting- contrivance.

   1 9 3. An ophthalmological device as claimed in Claim 2, wherein the end of the movable element thet extends from tile stationary element rests upon the end of the bellows accommodated inside the iousj-n,,7,.

   4. An ophthalmological device as claiLned in Claim 2 or 3, wherein the movable element is sprin-leaded with resPect to tile bellows accommouated inside the huusing by mearis of a sprinG fitUed over the movable element.

   5. An ophthalmological device es claimed in any one of Claims 2 to 4, wherein the other bellows is interposed between tivo surfaces which define a pressure-ex- f 9 - 16 erting contrivance in the form of a pedal.

   6. An ophthalmological device as claimed in any one of Claims 2 to 5. wherein the surgical instrument is in fact a detachable one. while the bellows end against which the movable element butts up serves as a parting face of the surgical instrument.

   7. An ophthalmological device as claimed in any one of Claims 4 to 6, wherein both the stationary element and the movable element are shaped as tubes of which the inner tube has a connector adapted for removal of tissues from patient's eye and located on the extending end of the movable element, which connector serves as a stop for the spring fitted on the movable element.

   8. An ophthalmological device as claimed in Claim 6, wherein forceps or scissors are used as the detechable surgical instrument.

   9. An ophthalmological device substantially as described hereinabove with reference to. and as illust- rated in the accompanying drawings.

   Published 1990atThePatentOffice. State House. 66;171 Highl-Iolborn, London WC1R4TP. Further copies maybe obtainedfrom The PatentOffice. Sales Branch, St Mary Cray, Orpington, Kent BR5 3F.D. Printed by Multiplex techniques ltd, St Mary Cray. Kent, Con. 1/87 7 eh