Abstract:
A cutting device for ophthalmologic surgery in the eye of a living being specifically for suctioning, cutting and removing portions of the vitreous humor of the eye and/or tissue particles, includes a housing and a probe disposed thereon for insertion into the vitreous humor with the probe including a guide tube with a suction opening at its distal end and an inner tube co-axially inserted therein which is slideably movable in axial direction relative to the suction opening, and a control member configured to translate a rotational movement of the drive into a linear movement of the inner tube to thereby move the inner tube in the guide tube in the direction of the longitudinal axis from the resting position to the closing position and back to the resting position while preventing a linear movement of the inner tube at rotating drive when the inner tube is in the resting position.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates, in general, to devices in ophthalmologic surgery, and more particularly to a surgical device for carrying out ophthalmologic procedures, in particular for suctioning, cutting and removing of portions of the vitreous humor and/or tissue particles of the eye of a living being. 
     U.S. Pat. No. 5,833,643 describes a device for use in surgical procedures which includes a housing with an electrical motor drive disposed therein and a tube disposed at the outside of the housing. An inner tube is arranged coaxially in the housing and connected to an aspiration line, and a wobble plate is operatively connected to a sliding sleeve which is attached to the shaft of the electrical motor drive and with which the inner tube is movable by an oscillation drive in an axial direction relative to the suction opening at the distal end of the outer tube. 
     In conventional devices or instruments, in particular those that are used for surgical removal of portions of the vitreous humor or removal of tissue particles from the vitreous humor of an eye, the oscillation drive not only generates undesirable vibration but also limits the device to grab, cut and withdraw only smaller pieces of tissue because opening and closing process with respect to the suction opening are simultaneous. Thus, when removing longer pieces of connected tissue, the procedural removal steps must be repeated two or more times. 
     SUMMARY OF THE INVENTION 
     It is thus an object of the present invention to provide an improved device for use in aspirating, cutting and removing of portions of the vitreous humor or tissue particles of the eye, which obviates the afore-stated drawbacks. 
     It is a further object of the invention to provide an improved device which does not produce vibrations that interfere with the surgical procedure and which allows rapid grasping and cutting of also larger pieces of connected tissue portions of the vitreous humor and immediate removing of these pieces. 
     These objects, and others which will become apparent hereinafter, are attained in accordance with the present invention by providing a housing, a guide tube disposed at the housing for insertion into a hollow space of the vitreous humor, with the guide tube having a distal end forming a suction opening, an inner tube received coaxially in the guide tube, a drive, and a control member operatively connected with the drive for moving the inner tube in the direction of the longitudinal axis between a resting position in which the suction opening of the guide tube is cleared to allow withdrawing the vitreous humor and/or tissue particles and a closing position in which the suction opening is sealed, said control member being configured to allow a movement of the inner tube in the guide tube in the direction of the longitudinal axis from the resting position to the closing position and back to the resting position by translating a rotational movement of the drive into a linear movement of the inner tube, and to refrain from acting on the inner tube at rotational movement of the drive when the inner tube is in the resting position. 
     In accordance with the invention, the device (high-speed cutter) does not produce vibrations that interfere with the surgical procedure and is able to reliably and quickly grab also larger pieces of connected tissue of the vitreous humor for subsequent removal. In operation, independently of the cutting frequency, the suction opening of the device according to the invention can be held in open position for a relatively long period to enable optimal aspiration, whereas closing and cutting of the differently shaped and dimensioned portions of the vitreous humor and the tissue particles can be carried out rapidly even when a great amount of material is being cut and removed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The above and other objects, features and advantages of the present invention will now be described in more detail with reference to the accompanying drawing in which: 
     FIG. 1 is a horizontal sectional view of an eye and a schematic illustration of a device according to the present invention, showing a probe for aspirating, cutting and removing portions of the vitreous humor and/or tissue particles from the cavity of the vitreous humor; 
     FIG. 2 is an enlarged partial sectional view of the device of FIG. 1, with the housing configured as a handle and integrated drive system; 
     FIG. 3 is an enlarged sectional view of the housing with integrated drive system for interaction with the probe; 
     FIG. 4 is an enlarged partial sectional view of the probe of the device as shown in FIG. 1, with an inner tube arranged coaxially in a guide tube and occupying a resting position; 
     FIG. 5 is a partial view of the probe of FIG. 4, with the inner tube shifted to a closing position with respect to the suction opening; 
     FIG. 6 is a sectional view of a headpiece for attachment to the housing according to FIG. 3; 
     FIG. 7 is a sectional view, partially broken away, of an intermediary piece of the housing according to FIG. 3; 
     FIG. 8 is a partial sectional view of a coupling member for connection to the drive system according to FIG. 3; 
     FIG. 8A is a plan view of the coupling member as shown in FIG. 8; 
     FIG. 8B is a side view of the coupling member of FIG. 8A; 
     FIG. 9 is a representation of a rotation body for connection to the drive system according to FIG. 3; 
     FIG. 9A is a plan view of the rotation body of FIG. 9; 
     FIG. 9B is a side view of the rotation body of FIG. 9A; 
     FIG. 10 is a plan view of a cylindrical control member formed with a curved track; 
     FIG. 10A is a sectional view of the control member according to FIG. 10; 
     FIG. 10B is a side view of the control member of FIG. 10A; 
     FIG. 11 is a graphic representation of the curved track of the control member of FIG. 10; and 
     FIG. 12 is a representation of several graphs of the movement pattern of the inner tube through interaction with the control member of FIG.  5 . 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Throughout all the Figures, same or corresponding elements are generally indicated by same reference numerals. 
     Turning now to the drawing, and in particular to FIG. 1, there is shown an enlarged schematic illustration of a horizontal sectional view of an eye  10  showing the cornea  1 , the iris  2 , the pupil  3 , the sclera  4  and the vitreous humor  5  and the vitreous humor space  5 ′, the lens  6 , the retina  7 , the ciliary body  8  with the zonula fibers  8 ′ and the optical nerve bundle  9 . Further shown in FIG. 1 is a schematic device  150  which has a probe  25  for insertion into the vitreous humor space  5 ′. At the front end, the elongated tubular probe  25  has a recess  21  shown schematically and configured for grasping and cutting portions  5 ″ of the vitreous humor and/or tissue particles as well as subsequent removal from the vitreous humor space  5 ′. The device  150  and the probe  25  can be turned manually about a longitudinal axis X in the direction of Y and moved in the direction of double arrow Z in axial direction. To prevent injury, the device  150  with the probe  25  can be inserted into a sleeve  15  inserted or disposed in the sclera  4  in the area of the pars plana  11 . 
     The device  150  is operatively connected to a drive unit  110  (shown schematically only) via an electric line  109  and to an aspiration unit  115  via an aspiration line  114  (shown schematically only). Operation and control of drive unit  110  and the aspiration unit  115  is effected, for example, by means of a pedal switch or a similar switch (not shown). 
     As shown in FIG. 2, the device  150  includes a hollow cylindrical housing  90 , which is configured as a handle, and a drive system, generally designated by reference numeral  100  and fitted in the housing  90 . At its rearward end, the housing  90  has a cap  93  for attachment of the electric line  109 . The cap  93  may be secured to the housing, for example, by a screwed connection (not shown). The housing  90  has an interior space  91  for accommodating a drive  95 , for example, an electric motor, and a rotation sensor  96  mounted to one end of the drive  95 . At its other end, the drive  95  has a shaft  94  which rotates about the longitudinal axis X (FIG.  3 ), with a fork-shaped rotation body  65  being mounted on the shaft  94 . 
     The drive system  100  as shown in FIG. 2, includes essentially the rotation sensor  96  disposed in the housing  90  and the electric motor drive  95  with the shaft  94 , the rotation body  65  connected to the shaft  94 , and a control member  45  which is in operative engagement with the rotation body  65  and a coupling member  35  which is operatively connected to the probe  25 . The rotation body  65  and the control member  45  as well as the coupling member  35  are disposed in coaxial relation in an intermediary piece  80  which is attached to the housing  90  by a screw connection. Mounted to the front end of the intermediary piece  80  is a headpiece  70  which carries the probe  25 , for example, via quick-release lock. The coupling member  35  has a connection piece  34  at one end for attachment of the aspiration line  114  in any suitable manner. The aspiration line  114  is guided through a recess  75  in the intermediary piece  80  outwardly for connection to the aspiration unit  115  (FIG. 1 ). 
     In accordance with FIG. 2, the headpiece  70  is pushed in axial direction over the intermediary piece  80  and turned by 90° relative to the intermediary piece  80  for realizing a secure connection via the quick-release lock. 
     Turning now to FIG. 3, there is shown a sectional view, on an enlarged scale, of the drive system  100  disposed in the housing  90 . The electric motor drive  95  is, for example, held in the interior of the housing  90  by a retainer ring  82  and screw fasteners  83 . The rotation body  65  which is operatively connected to the front end of the shaft  94  by a threaded pin  84  or similar fastener, rotates about the longitudinal axis X in the direction of arrow Y when activating the drive  95 . A seal  60  is mounted on the shaft  94  between the retainer ring  82  and the rotation body  65 , disposed in a first recess  79  of the intermediary piece  80 , and is secured against axial displacement by a disk  58  and a spacer ring  55 . The spacer ring  55  has an outer annular groove  56  for receiving a seal  57 , such as an O-ring, and is secured against axial displacement by the intermediary piece  80  which is threadably engaged in the housing  90 . 
     FIG. 3 further shows the cylindrical control member  45  which is formed on one end with the curved track  50  and disposed in a second recess  79 ′ of intermediary piece  80 . A pin  62  projects inwardly from the fork-shaped rotation body  65  into the curved track  50 , so that a rotation of the shaft  94  about the longitudinal axis X in the direction of Y results in movement of the pin  62  in the curved track  50  of the control member  45 . The control member  45  has a recess  48  in the shape of a groove or slot, and an axial groove  49  for engagement of a pin  81  to thereby secure the control member  45  against rotation when the control member  45  moves in axial direction. 
     The coupling member  35  is mounted to the other end of the control member  45  and includes a plate  38  for positive engagement in a slot-shaped groove  53  of the control member  45 . The coupling element  35  is further formed with a flange  36  in spaced-apart relation to the plate  38  for engagement in a first recess  71  of headpiece  70 . A pin  40  with a stop member  41  is mounted to the headpiece  70  for so engaging a recess ( 36 ′) in the outer circumference of the flange  36  that the coupling member  35 , which conjointly moves in axial direction with the control member  45 , is secured against rotation. The coupling member  35  thus is connected to the aspiration line  114  at one end via the connection piece  34 , and at its other end in operative connection (not shown) with inner tube  30  of the probe  25 . 
     As shown in FIG. 3, the intermediary piece  80  has an outer thread  78 ′ which is in mesh with the inner thread  92  of the housing  90 . In assembled state, the headpiece  70  may be sealed against the intermediary piece  80 , for example, by an O-ring  42  bearing upon an end face of the cylindrical segment  76  which is inserted into a recess  72  of the headpiece  70 . The headpiece  70  with the elongated tubular probe  25  is detachably secured to the intermediary piece  80  by a pin-shaped locking cam  69  in the form of a bayonet-type locking mechanism. In FIG. 3, the headpiece  70  is coupled to the intermediary piece  80  and a rotation of the headpiece  70  about an angle of 90° about the longitudinal axis X results in a locked engagement of the locking cam  69  in a bore  74  of the intermediary piece  80 . (FIG.  7 ). 
     Referring now to FIG. 4, there is show an enlarged sectional view of the front end of the probe  25  which includes an outer guide tube  20  and an inner tube  30  which is received coaxially in the guide tube  20  and can move in a direction of double arrow Z′. The outer guide tube  20  is closed at its forward end by an end wall  22 . At a distance to the end wall  22 , the guide tube  20  has a recess  21  which is referred to in the following description as suction opening  21 . To improve guidance and coaxial centering of the inner tube  30 , the guide tube  20  is formed in the area of the recess  21  with axial segments  24 ,  24 ′ which are provided in offset relation. FIG. 4 shows a resting position in which the inner tube  30  is retracted relative to the end wall  22  of the guide tube  20 , so that the recess  21  is open to allow aspiration of tissue particles  5 ″ (FIG.  1 ). 
     Persons skilled in the art will understand that the probe  25  is shown here in exaggerated illustration for ease of understanding. In reality, the dimensions of the probe  25  for insertion into the cavity  5 ′ of the vitreous humor  5 , are in accordance with a preferred non-limiting embodiment such that the guide tube  20  has an outer diameter of approximately 0.91 mm and the coaxial inner tube  30  has an outer diameter of approximately 0.63 mm. The suction opening  21  at the distal end of the guide tube  20  has an axial length of approximately 0.7 mm. 
     FIG. 5 shows a closing position in which the inner tube  30  is shifted toward the end wall  22 , thereby sealing the suction opening  21 . The end face  28  of the inner tube  30 , confronting the end wall  22  of the guide tube  20 , is configured as a cutting edge (not shown here in detail) and severs tissue particles  5 ″ (FIG.  1 ), drawn through aspiration via the suction opening  21  into the inner space  23  of the guide tube  20 , as the inner tube  30  moves toward the end wall  22 . Subsequently, the severed tissue particles  5 ″ are forced through axial channel  29  of the inner tube  30  and removed via the aspiration line  114 . 
     FIG. 6 shows a sectional view of the headpiece  70  and the probe  25  attached thereto. The guide tube  20  may be secured to the headpiece  70  by gluing or any other suitable manner. The headpiece  70  has a forward cylindrical recess  71  and a rearward cylindrical recess  72  of greater diameter than the recess  71 , thereby defining a shoulder formed with a ring groove  73  for receiving the seal  42  (FIG.  3 ). A locking pin  69  is suitable secured in a circular wall section  72 ′ of the headpiece  70  and projects inwardly from the circular wall  72 ′ into the recess  72 . 
     Turning now to FIG. 7, there is shown a partially broken away view of the intermediary piece  80  which includes a first cylindrical segment  76 , a second cylindrical segment  77  and a third segment  78  integrally formed with the segment  77  and provided with an outer thread  78 ′. The intermediary piece  80  has a first cylindrical axial recess  79  of relatively greater diameter and a second cylindrical recess  79 ′ of relatively smaller diameter. Further shown in FIG. 7 is the approximately slot-shaped axial recess  75  for receiving the aspiration line  114 . (FIG.  2 ). A pin  81  is suitably secured to the segment  77  and projects inwardly from the segment  77  into the recess  79 ′, for securing the control member  45  (FIG. 3) against rotation when the pin  81  projects into the recess  79 ′ of the intermediary piece  80 . 
     The first cylindrical segment  76  of the intermediary piece  80  is provided with a bore  74  which extends partially in circumferential direction. The bore  74  is configured so that the headpiece  70 , which can be pushed over the first cylindrical segment  76 , engages with the locking cam  69  in bore  74  so that a turning of the headpiece  70  about the longitudinal axis X at an angle of about 90° in the direction of arrow Y′ results in a secure attachment the intermediary piece  80  as a result of the afore-mentioned bayonet-type locking mechanism which permits a rapid release of the headpiece  70  from the intermediate piece  80 , and the housing  90 , when cleaning and/or disinfecting of the probe  25  and/or a replacement of the entire headpiece  70  is desired. 
     FIG. 8 is a detailed view of the coupling member  35  which includes a cylindrical core  37  having formed therein a throughbore  39  and carrying in spaced-apart relationship the front flange  36  and the plate  38 . The rearward end of the cylindrical core  37  is configured as a cylindrical connecting piece  34  which is offset for attachment of the aspiration line  114  (FIG.  2 ). 
     The coupling piece  35  is shown in FIG. 8A in plan view and in FIG. 8B in side view, showing the flange  36  which is configured as a circular disk with the recess  36 ′ at its outer circumference, the cylinder core  37  with the throughbore  39  and the connecting piece  34 , and the plate  38  which extends vertically and transverse to the longitudinal direction of cylinder core  37  (FIG.  8 B). 
     FIG. 9 shows the fork-shaped rotation body  65  which includes a disk-shaped side portion  66 , and two fork arms  63  and  64  formed on the side portion  66  in spaced-apart relation. The pin  62  is attached to the fork arm  63  in a suitable manner. The side portion  66  has a throughbore  67  and a threaded bore  68  extending transversely to the throughbore  67 . In the assembled state, as shown in FIG. 3, the shaft  94  of the electric motor drive  95  is received in the throughbore  67  and secured by the threaded pin  84 . 
     FIGS. 9A,  9 B show a plan view and a side view, respectively, of the rotation body  65  to illustrate again the side portion  66  with throughbore  67  and threaded bore  68 . Mounted to the side portion  66  are the parallel fork arms  63  and  64 , with the fork arm carrying the pin  62 . The fork arms  63 ,  64  oppose one another on the side portion  66  to define confronting inner sides  63 ′ and  64 ′ which are configured of substantially circular arc shape to complement the cylindrical control member  45 . 
     FIG. 10 shows a plan view of the cylindrical control member  45  which has one end formed with the groove  53  located at a distance to the end wall  45 ′ and extending transversely to the longitudinal axis X. At its other end, the control member  45  is provided with the curved track  50  at a distance to the rear wall  45 ″. Starting from the end wall  45 ′, the control member  45  is further provided with an elongate axial recess and a corresponding longitude groove  49  at the outer circumference. The curved track  50  in the control member  45  is bounded by a cylindrical core  50 ′ has an approximately groove-shaped or a slot-shaped configuration. The curved track  50  is composed in circumferential direction essentially of two circular shaped interconnected segments, with one segment having side walls  51  and  52  which are oriented orthogonal relative to the longitudinal axis X, and with the other segment having side walls  51 ′ and  52 ′ which are curved at an inclination in the direction of the rear wall  45 ″ of the control member  45 . The side walls  51 ,  52  and  51 ′,  52 ′ of the curved track  50  disposed circumferentially on the control member  45  are arranged in spaced apart parallel relation. The distance between the spaced-apart side walls  51 ,  52  and  51 ′,  52 ′ of the curved track  50  is so selected that the pin  62  of the rotation body  65  rotating about the longitudinal axis X is guided precisely in the track  50 , thereby effecting the axial movement of the control member  45  together with the coupling member  35  and the inner tube  30 . 
     FIGS. 10A and 10B show a longitudinal section and a side view of the control member  45 , illustrating in detail the cylindrical segment  46  bounded at one end by the end wall  45 ′ and at the other end by the rear wall  45 ″. Spaced from the rear wall  45 ″ is the circular curved track  50  with side walls  51 ,  51 ′ and  52 ,  52 ′. The axial recess  48  is disposed in the cylindrical segment  46  and extends to the front wall  45 ′. As a consequence of the axial recess  48 , the end wall  45 ′ is subdivided in two wall segments  54  and  54 ′. At its outer circumference, the cylindrical segment  46  is further provided in axial direction with the longitudinal groove. Formed at a distance to the end wall  45 ′ is the groove  53  which extends transversely to the longitudinal direction and is bounded by the two inner walls  53 ′ and  53 ″ (FIG.  10 B). FIG. 10B further shows the recess  48  and the two segment-shaped wall portions  54  and  54 ′. 
     After having described the components of the device  150 , its mode of operation will now be described in more detail. A reliable aspiration and cutting function requires an exact calibration and fixation of the axially movable inner tube  30  with respect to the suction opening  21 . In order to attain this precondition, the rotation sensor  96  generates two phase-shifted electrical signals in dependence to the rotational movement. These signals are used, on the one hand, to detect and determine the current rotational direction of the drive  95  and, on the one hand, to detect and determine the current position (first reference point) of the inner tube  30  relative to the suction opening  21  at the distal end of the guide tube  20 . 
     The first reference point (FIG. 4) is determined by rotating the electric motor drive  95  and thereby shifting the inner tube  30  in axial direction toward the suction opening  21  while the aspiration unit  115  is switched on, until the vacuum rises and upon reaching a second reference point (FIG. 5) and complete sealing of the suction opening  21  (FIG.  5 ), the absolute value of the vacuum has been reached. The axially spaced two reference points are arranged at a distance relative to each other as a result of the interaction between the shaft  94 , the rotation body  65  and the control member  45  at an angle of rotation of 180° in axial direction. The first reference point establishes the resting position in which the suction opening  21  is completely open (FIG.  4 ), and the second reference point establishes the closing position in which the suction opening  21  is sealed. 
     FIG. 11 is a graphical illustration of the movement pattern of the control member  45  as result of the interaction between the curved track  50  and the pin  62 , as plotted in degrees of rotation. The curved track  50  is suitably configured such that when the shaft  94  together with the rotation body  65  move about longitudinal axis X in a rotation movement at an angle from 0° to 360°, the following rotation phases P 1  through P  4  are realized to implement the movement pattern in axial direction of the control member  45  through interaction with the rotation body  65 : 
     a) in the first rotation phase P 1  about rotation angle from 0° to 90°, the pin  62  of the fork-shaped rotation body  65  runs idle in the curved track  50  so that no axial displacement of the control member  45  is effected, and the inner tube  30  remains stationary at a distance to the suction opening  21  (resting position); 
     b) in the second phase P 2  about rotation angle from 90° to 180°, the control member  45  is moved by the pin  62 , resulting in an axial displacement of the control member  45  and thus in a axial movement of the inner tube  30  into the closing position, designated P max  in FIG. 11, in which the suction opening  21  is sealed; 
     c) in the third rotation phase P 3  about rotation angle from 180° to 270°, the control member  45  with the inner tube  30  are returned in axial direction to the starting (resting) position in which the suction opening  21  is cleared again; and 
     d) in the fourth rotation phase P 4  about rotation angle from 270° to 360°, the pin  62  runs idle again so that the control member  45  is not activated and the inner tube  30  remains stationary at a distance to the suction opening  21 . 
     During the afore-described rotation phases P 1  to P 4 , the rotational movement of the shaft  94  is translated from the pin  62  of the rotation body  65  to the control member  45  and the inner tube  30  in such a way that during the rotation phase P 1  at the rotation angle of 0° to 900°, the inner tube  30  remains in the resting position with open suction opening  21  open. In the following rotation phase P 2  of rotation body  65  at rotation angle of 90° to 180°, the control member  45  with inner tube  30  is moved in axial direction for sealing the suction opening  21 , and in the rotation phase P 3  about rotation angle from 180° to 270°. the suction opening  21  is cleared again. The following rotation phase P 4  about rotation angle from 270° to 360° is analog to rotation phase P 1 , so that the control member  45  with the inner tube  30  remains in the resting position with open suction opening  21 . The time period of the rotational phases P 1  and P 4  for aspirating tissue particles is at least as long as the combined time period of rotation phases P 2  and P 3  for closing and subsequent reopening of the suction opening  21  in the outer guide tube  20 . 
     It should be noted, when switching off the device  150  (FIG.  2 ), the electric motor drive  95  is always stopped by the rotation sensor  96  at the moment when the suction opening  21  is cleared by the inner tube  30  and thus open (FIG.  4 ). This ensures, that whenever the device  150  is started, tissue particles  5 ″ can be drawn through the suction opening  21  and subsequently severed as the inner tube  30  moves axially relative to the suction opening  21  of the outer guide tube  20 . 
     FIG. 12 shows a graphic representation of a addition of the rotational phases plotted in a coordinate system in connection with the movement patterns and resultant movements. Starting with P l  (point of intercept) the coordinate system at a point of intersection on the abscissa referred to as R A  (rotation angle), a number of rotations are shown here. On the ordinate referred to as L M  (lifting motion), the respective “open” and “closed” positions of the suction opening  21  in the guide tube  20  can be seen as a result of the axially directed movement of the control member  45  by means of the curved track  50 . The various rotation phases P 1  to P 4  of shaft  94  and the resultant movement patterns in axial direction of the control member  45  and the coupling member  35  together with the inner tube will now be described: 
     As shown schematically in FIG. 12, beginning from the point of intersection P l , in the first rotation phase P 1 ′ at a rotation angle R A  from 0° to 90° no movement L M  is registered and thus no axial displacement of any of components  45 ,  35 , and  30  takes place, so that during this phase, the suction opening  21  in the guide tube  20  remains in open position (first reference point). 
     In the following second rotation phase P 2 ′ about rotation angle R A  from 90° to 180°, a first movement L M  is realized which effects an axial displacement of components  45 ,  35  and  30  until the end position designated with P′ max . In this phase, the suction opening  21  of the guide tube  20  is sealed by the inner tube  30  which moves axially to the closing position, shown in FIG. 5 (second reference point). 
     In the following third rotation phase P 3 ′, about rotation angle from 180° to 270°, beginning from the end position P′ max , a reversal of the first motion L M  occurs and results in an axial displacement of the components  45 ,  35  and  30  such that the inner tube  30  subsequently clears the suction opening  21  and returns to the resting position as shown in FIG.  4 . 
     The suction opening  21  is in open position during the following fourth rotation phase P 4 ′, about rotation angle R A  from 270° to 360° and/or when the shaft  94  together with rotation body  65  rotates about rotation angle R A  from 270° to 450°. 
     The device according to the invention  150  ensures a relatively vibration-free operation even at high cutting rate while yet attaining optimal performance as far as aspiration of tissue particles is concerned. In addition to the high cutting rate, a precise control of the electric motor drive  95  ensures also a small number of single cuts so that its application is possible also at so-called problem areas. 
     While the invention has been illustrated and described as embodied in a device for use in ophthalmologic procedures, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention. What is claimed as new and desired to be protected by letters Patent is set forth in the appended claims: