fig1 and 1a show an iol 11 which generally comprises an optic 13 and fixation members 15 and 17 . in this embodiment , the optic 13 may be considered as including an optical portion 19 for focusing light on or near the retina of the eye and a cell barrier portion 21 circumscribing the optical portion and being incapable of focusing light on the retina . optical axis 22 passes through the center of optic 13 in a direction generally transverse to the plane of the optic . in this embodiment , the optic 13 is circular in plan and biconvex ; however , this is purely illustrative as other configurations and shapes may be employed . the optic 13 may be constructed of any of the commonly employed materials commonly used for rigid optics , such as polymethylmethacrylate ( pmma ), or commonly used for resiliently deformable optics , such as silicone polymeric materials , acrylic polymeric materials , hydrogel - forming polymeric materials , mixtures thereof and the like . the fixation members 15 and 17 in this embodiment are generally c - shaped and are integral with the optic 13 . however , this is purely illustrative as the fixation members 15 and 17 may be of other configurations and / or may be separate members affixed to the optic in any of a variety of conventional ways . the optic 13 has an anterior face 23 , a posterior face 25 and a peripheral edge 27 . in this embodiment , the faces 23 and 25 are convex and the peripheral edge 27 is cylindrical , but as indicated above , these shapes are shown only by way of example . the optic 13 is designed to be placed in the capsular bag . the diameter of the optic 13 may be conventional , and as such , may be about 6 mm or less . the optical portion 19 performs the normal function of the optic of an iol , i . e . to appropriately focus light at or near the retina . the optical portion 19 may be monofocal or multifocal . in this embodiment , the cell barrier portion 21 is integral with the optical portion 19 . the cell barrier portion 21 is incapable of focusing light on the retina of the eye and includes an irregularly configured structure or surface feature effective to inhibit , and preferably substantially prevent , cell growth radially inwardly across the cell barrier portion . in the embodiment of fig1 - 6 , the cell barrier portion 21 includes a concentric array of annular grooves 29 each of which is at least partially defined by irregular surfaces . similar arrays of the grooves 29 are in both the anterior face 23 and the posterior face 25 . although various different arrangements can be employed , in this embodiment the grooves 29 are concentric and substantially equally spaced apart . each of the grooves 29 has sufficient irregularity in its structure so as to at least inhibit migration of cells across the groove . for this purpose , each of the grooves 29 has a maximum depth of no more than about 0 . 02 mm and a maximum width at the face 23 ( or face 25 as the case may be ) of no more than about 0 . 005 mm or about 0 . 01 mm or about 0 . 02 mm . in addition , the grooves 29 are substantially completely defined by irregular surfaces . in particular , each of the grooves 29 is represented by other than straight lines having a length more than about 0 . 001 mm , with the groove viewed in axial cross - section along a plane which includes the optical axis 22 . this irregularity of grooves 29 is illustrated in detail in fig5 . fig6 is a photograph of a number of the grooves 29 which demonstrate their substantial irregularity . without wishing to limit the invention to any particular theory of operation , it is believed that the irregularly configured structure of cell barrier portion 21 , for example , grooves 29 , acts to disrupt or otherwise interfere with the process of eye cell , for example , lens epithelial cell , migration or growth so that the cumulative effect of this irregular structure is to significantly reduce , or even eliminate , the migration or growth of cells in front of or in back of the optical portion 19 after iol 11 is implanted in the eye . fig4 illustrates that eye cells 30 from the capsular bag 32 do migrate or grow to some extent onto and cover a portion of the cell barrier portion 21 . this limited cell migration is advantageous in at least assisting or facilitating the effective fixation of iol 11 in the eye . thus , the present invention preferably provides for such advantageous limited eye lens epithelial cell migration or growth while preventing excessive cell migration or growth in front of or in back of the optical portion 19 , as shown in fig4 . another way of viewing the degree of irregularity of the irregularly configured structure , for example , grooves 29 , on cell barrier portion 21 is opacity . the grooves 29 are sufficiently irregular so that the cell barrier portion 21 is substantially completely opaque to the transmission of light . when viewed by the naked eye , cell barrier portion 21 is a white or frosty band on the otherwise optically clear optic 13 . the irregularity of grooves 29 is in contrast to the regular or ordered grooves of the prior art , for example , the linear ordered grooves disclosed in kelman u . s . pat . no . 4 , 808 , 181 . the kelman grooves are defined as being ordered whereas the present grooves , such as grooves 29 , are defined by irregular , even randomly or unordered , surfaces , as described elsewhere herein . under 1000 times magnification , the kelman grooves are still defined ( in axial cross - section ) by straight lines . fig5 and 6 show that grooves 29 , in accordance with the present invention , are not defined ( in axial cross - section ) by straight lines . also , although the region of the kelman iol which includes the linear ordered grooves may be somewhat distorted ( not totally optically clear ), this region still remains substantially transparent to the passage of light . in contrast , the present grooves 29 and cell barrier portion 21 are substantially opaque to the transmission of light . as noted above , the irregularity of the present cell barrier portion is an important aspect of the present invention in inhibiting the migration of eye cells onto the optical portion of the optic and clearly distinguishes the present iols from prior art iols , such as the iols of kelman u . s . pat . no . 4 , 808 , 181 and the like iol which included regular or ordered surface grooves and the like features . preferably , the radial dimension of the cell barrier portion 21 is no greater than about 2 mm , and more preferably no greater than 0 . 25 mm . in the embodiment shown in fig1 to 6 , the spacing between the grooves 29 along the face 23 may be about 0 . 005 mm to about 0 . 02 mm and the radial spacing between the outermost groove 29 and the peripheral edge 27 may be about 0 . 02 mm to about 0 . 1 mm . in the embodiment shown in fig1 to 6 , the number of grooves 29 is about 50 to about 100 . in order to obtain an advantageous degree of cell migration inhibition , it is preferred that the number of grooves included in cell barrier portion 21 be at least about 20 , although fewer grooves can provide some useful benefits . the grooves 29 are located wherever it is desired to inhibit cell migration . in the present embodiment , the grooves 29 are placed on both the anterior face 23 and the posterior face 25 so that the cell barrier portion 21 is on both faces of the optic 13 . however , the cell barrier portion can be eliminated from a particular face if it is determined that cell migration in front of that face is not likely to occur . the iol 11 can be implanted in the capsular bag of the eye in accordance with conventional techniques . when so implanted , the cell barrier portion 21 defines a radially relatively narrow annular barrier for inhibiting cell growth radially inwardly in front of or in back of the optical portion 19 where the cells could cause secondary opacification . the present invention is applicable to iols including a hard or rigid optic , such as the optics made from pmma , and those which include a foldable or deformable optic , such as optics comprising silicone polymeric materials , other acrylic polymeric materials , hydrogel - forming polymeric materials , such as polyhydroxyethylmethacrylate ( poly hema ), and the like . such foldable / deformable optics are particularly advantageous since they can be inserted into the eye through a small incision . the fixation members 15 and 17 , are flexible and strandlike or filaments so that they can be easily inserted into the eye . the fixation members 15 and 17 can be formed integrally with the optic 13 or can be separately coupled to the optic . fig7 and 8 show an iol 11a which is identical to the iol 11 in all respects not shown or described herein . portions of the iol 11a corresponding to portions of the iol 11 are designated by corresponding reference numerals followed by the letter a . the only difference between the iol &# 39 ; s 11 and 11a is that in the iol 11a the grooves 29 are replaced with an irregularly roughened or textured surface 31 . the cell barrier portion 21a , in particular the roughened or textured surface 31 , is sufficiently irregular as to be at least partially , and preferably substantially completely , opaque to the transmission of light . this not only provides cell migration inhibition , but also avoids glare from the interaction of light with the cell barrier portion 21a . the textured surface 31 may be textured or roughened in any of a variety of ways including machining as with a lathe , chemical etching , abrading or the like . if the optic 13a is molded , as for example when it is constructed of silicone polymeric material or other soft foldable material , the texturing or roughening of the textured surface 31 may be imparted by the mold . the degree of irregularity of the roughening of the surface 31 should be sufficient to enable the textured surface to perform the inhibition of cell migration function . fig9 and 10 show an iol 11b which is identical to the iol 11 in all respects not shown or described herein . portions of the iol 11b corresponding to portions of the iol 11 are designated by corresponding reference numerals follows by the letter b . there are two primary differences between the iol &# 39 ; s 11b and 11 . first , in the iol 11b , the fixation members 15b and 17b are separate strands or filaments which are attached to the optic 13b in a suitable conventional manner . secondly , the cell barrier portion 21b is in the form of a separate member coupled to the optical portion 19b . in this embodiment , the cell barrier 21b includes spaced members 33 joined by a web 35 . the members 33 engage the faces 23b and 25b , respectively , and the web 35 confronts and engages the peripheral edge 27b . the cell barrier portion 21b is annular and extends completely around the optical portion 19b and is mounted on the optical portion in a manner similar to a tire . the cell barrier portion 21b may have a radial width of up to about 2 mm or about 1 mm , for example , about 0 . 25 mm . while this invention has been described with respect to various specific examples and embodiments , it is to be understood that the invention is not limited thereto and that it can be variously practiced within the scope of the following claims .
an iol implantable in an eye including an optic having an optical portion for directing light toward the retina of the eye and a cell barrier portion for inhibiting cell growth from the eye in front of or in back of the optical portion . the cell barrier portion circumscribes the optical portion , is incapable of focusing light on the retina and includes an irregularly configured structure , for example , irregular grooves . at least one elongated fixation member is coupled to the optic for use in fixing the optic in the eye .