Patent Publication Number: US-2023149113-A1

Title: Methods and apparatus for wide angle chandelier illuminator

Description:
PRIORITY CLAIM 
     This application claims the benefit of priority of U.S. Provisional Patent Application Ser. No. 63/264,183 titled “METHODS AND APPARATUS FOR WIDE ANGLE CHANDELIER ILLUMINATOR,” filed on Nov. 17, 2021, whose inventors are Qing Xiang, Timothy C. Ryan, and Yu Yan, which is hereby incorporated by reference in its entirety as though fully and completely set forth herein. 
    
    
     BACKGROUND 
     During eye surgery (e.g., involving a vitrectomy) the eye may be illuminated. Visualization, directly or through a microscope, may be enhanced through the use of a chandelier light instrument. During eye surgery, a vitrectomy probe needle and the main body of the chandelier may each be inserted through a pre-placed cannula at the surface of the eye. Each cannula provides a structurally supportive conduit strategically located at an offset location at the front of the eye, such as the pars plana. In this way, the probe needle or the chandelier may be guidingly inserted into the eye in a manner that avoids damage to the patient&#39;s lens or cornea. 
     Of course, in order to achieve a successful vitrectomy or other such intervention, some additional tools may be required. This means that if the light instrument is handheld along with a more interventional tool such as a vitrectomy probe, the probe will need to be removed and replaced with the other tool. In this way, the surgeon may maintain a hand dedicated to holding of the light instrument. Of course, another surgeon or medical assistant might maintain the light instrument in place so as to keep both of the surgeon&#39;s hands freed up for manipulating more interventional tools. However, in the limited space confines of a surgery directed at an eye, this may not be practical. Once more, the surgeon giving up manipulative control over the light instrument may present a challenge in terms of directing light precisely at the region of the eye intended by the surgeon. 
     As an alternative to maintaining manual control over the light instrument, a prepositioned chandelier instrument may be utilized. More specifically, a flexible chandelier illuminator may be immobilized by a cannula (or inserted directly) at the eye and bent into a stable position. Thus, the light instrument may be set in place for the duration of the eye surgery. This leaves the surgeon free to personally manipulate multiple other interventional tools without concern over maintaining control over the light instrument. 
     Visibility or illumination challenges exist for a variety of reasons. However, one of the primary reasons is because of size and dimensional constraints. For example, due to advancements in terms of minimal invasiveness, a conventional chandelier light instrument may generally be smaller than about 25 gauge. This is an incredibly small amount of architectural footspace with which to work. As a result, light distribution from the fiber optic end of the light instrument may display a degree of a focused spot with illumination fairly focused within a narrow targeted location of the eye. 
     Another reason for the less than ideal distribution of light is the fact that the small gauge dimensions of the fiber optic end are geometrically provided by way of a cutting instrument during manufacturing. That is, the fiber optic end component of the light instrument is shaped by a cutting instrument to terminate the end and provide a degree of a taper. Ideally, the tapering of the fiber optic end by way of the cutting instrument will provide an improved degree of light distribution. 
     Unfortunately, the cutting of the fiber optic end is likely to result in a shaped surface that may be scratched and compromised in terms of light distribution. Thus, while there may be some improvement in light distribution due to the tapered cut, the effect is minimized. Generally speaking, due to limitations in light distribution, the surgeon may need to manually manipulate the light source in order to ensure light being directed where intended throughout the eye surgery. 
     SUMMARY 
     An instrument for affixation in support of an eye surgery. The instrument includes an optical end of enhanced light emitting architecture. Specifically, the instrument includes a base of substantially constant diameter that supports a tapering terminus extending from the base. The terminus is of a predetermined length with an angled taper, also of predetermined angularity. Once more, the surface of the terminus is uniquely ground with substantially scratch-free and uniform light scattering characteristics. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a side cross-sectional view of an embodiment of a chandelier instrument optical end of unique architecture and surface to support eye surgery. 
         FIG.  2    is a perspective overview of a grinding system to facilitate unique surfacing for the optical end of  FIG.  1   . 
         FIG.  3    is a partially sectional overview of an eye prepared for a surgery facilitated by the instrument and optical end of  FIG.  1   . 
         FIG.  4    is a partially sectional overview of the eye during a surgery facilitated by the instrument and optical end as shown in  FIG.  3   . 
         FIG.  5    is a chart highlighting a targeted manufacturability window for various architectures of the optical end of the instrument of  FIG.  1   . 
         FIGS.  6 A and  6 B  are flow-charts summarizing embodiments of manufacturing and employing an optical end of a chandelier instrument to facilitate eye surgery. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, numerous details are set forth to provide an understanding of the present disclosure. However, it will be understood by those skilled in the art that the embodiments described may be practiced without these particular details. Further, numerous variations or modifications may be employed which remain contemplated by the embodiments as specifically described. 
     Embodiments are described with reference to certain types of vitrectomy probe surgical procedures. In particular, a procedure in which vitreous humor is removed to address vitreous hemorrhage is illustrated. However, tools and techniques detailed herein may be employed in a variety of other manners. Specifically, embodiments of chandelier instruments may be utilized to facilitate tools such as a vitrectomy probe in addressing retinal detachments, macular pucker, macular holes, vitreous floaters, diabetic retinopathy or a variety of other eye conditions. Regardless, so long as the surgical procedure is aided by the use of a light instrument having an optical end of unique architecture and grind surface for enhanced lighting of the eye interior, appreciable benefit may be realized. 
     Referring now to  FIG.  1   , a side cross-sectional view of an embodiment of a chandelier instrument optical end  100  is illustrated that is of unique architecture and surface  175  to support eye surgery. The optical end  100  may be comprised of a fiber optic thread with a base  125  that is manufactured with an end cone  150 . With added reference to  FIG.  3   , the end cone  150  is tapered as illustrated to ultimately distribute a wide beam spread angle and light distribution ( 330 ). Ultimately, even though the chandelier instrument  350  that incorporates the optical end  100 , may be at a fixed location during surgery, sufficient light may be spread throughout the interior of the eye  350  without the need for any repositioning of the instrument  350 . 
     In the embodiment shown, the base  125  may be between about 300 micrometers and 600 micrometers in diameter with the end cone  150  tapering down from there. This may be consistent with current 23-29 gauge instrumentation. In the embodiment shown, the taper of the end cone  150  may extend to under about a millimeter in length (L), perhaps between about 700 and about 850 micrometers. As illustrated, there is a taper that runs across this length to provide the cone appearance and character to the end cone  150 . In the embodiment shown, this taper may be defined by an angle (a) that is greater than about 8.5°. More specifically, the angle (a) may be between about 9° and 13°. As described below, when combined with a grinded end cone surface  175 , this type of architecture provides a distribution of light  330  with a wide beam spread angle (θ) in excess of 100° (see  FIG.  3   ). As used herein, the term “spread angle” refers to an angle that is evaluated in terms of conventional Full Width Maximum (FW5% M) standard. However, other illumination metrics may be applicable. 
     In the embodiment shown, the end cone  150  is outfitted with a blunt end  160 . The blunt end  160  shape may merely avoid an end cone  150  with an impractically sharpened terminus that might be prone to breaking or cracking in a manner that might present optical or other performance issues to the optical end  100 . Nevertheless, as with the cone surface  175 , the face of the blunt end  160  may be formed by grinding and/or polishing as described further below. Whatever the case, as with the cone surface  175 , conventional mechanical cutting may be avoided so as to mitigate the possibility of scratching or other non-diffusive or non-uniform surface characteristics. 
     Referring now to  FIG.  2   , a perspective overview of a grinding system  100  to facilitate unique surfacing for the optical end  125  of  FIG.  1   . That is, with added reference to  FIG.  1    as indicated above, forming of the surface  175  is achieved, at least in part, through a grinding technique rather than conventional cutting. In this way, the end cone  150  is left with a surface  175  of enhanced light distribution character. In the embodiment shown, the system  200  includes a grind plate  240  to facilitate a tailored circular grinding of a grind pad  275  secured thereto. In one embodiment, the circular grinding takes place in an irregular manner with the center of the rotating plate  240  shifting location as the pad  275  is rotated. Further, as used herein, the term “grinding” may refer to a grinding with a courser material of the pad as described below or a finer polishing. Regardless, the surface  175  of the end cone  150  from a uniform diameter fiber optic to a shape of the end cone  150  is achieved by way of a less abrasive technique than what is attainable through conventional cutting. 
     Continuing with reference to  FIG.  2   , the grind plate  240  and pad  275  are directed by a drive located below at a grind table  260 , although other system configurations may be utilized. Other hardware of the system  200  includes an orienting device  225  or work holder that is angled to present a tubular extension  250  to the pad  275 . Thus, the fiber optic end  125  may presented to the pad  275  at the intended orientation for forming the tapered end cone  150  with angle (a) as illustrated in  FIG.  1   . The pad  275  may include a grinding film. In one embodiment, the film is a 12 micrometer aluminum film that may incorporate silicate or diamond particles for fine grinding or polishing of the fiber optic to the end cone  150  shape and form. In other embodiments, the film may range between about 1 and about 40 micrometers. Thus, the process may be considered as ranging from polishing to grinding, either of which may be referred to as grinding herein. Regardless, an enhanced taper geometry and surfacing for increasing spread angle and smooth light distribution as discussed further below may be attained. 
     The taper forming process of the end cone  150  through grinding as described may include periodic rotation of the fiber optic by or within the tubular extension  250 . The work holder/orienting device  225  may be used to guide and maintain tilted rotation of the fiber optic until the end cone  150  shape is attained. At the same time, guided rotation of the pad  275  according to a predetermined protocol is also maintained by the system  200 . In one embodiment, the end cone  150  is formed with a pointed terminus that is later polished or grinded to the blunt end  160  of  FIG.  1    with the same system  200  by re-orienting the orienting device  225  to a vertical or perpendicular orientation relative the pad  275  to continue the process and to form the blunt end  160 . 
     In the embodiment shown, note that an instrument sleeve  280  is present, emerging from the extension  250 . This sleeve  280  may be a structural component present in the finalized form of the light instrument  300  as illustrated in  FIG.  3    and may also provide added stability or security to the underlying fiber optic during the described grinding process. In the embodiment shown, the instrument  300  of  FIG.  3    may be a 27 gauge instrument, largely determined by the sleeve  280  dimensions which constitute the largest portion of the instrument  300  set to traverse a preplaced cannula  325  as described below. However, other suitable sizing may be employed. 
     Referring now to  FIG.  3   , a partially sectional overview of an eye  350  is illustrated that is prepared for a surgery facilitated by the instrument  300  and optical end  100  of  FIG.  1   . In this view, the fixed nature of the chandelier instrument  300  is apparent. This means that instead of being handheld, the instrument  300  is located at a fixed position such that further advancement of the optical end  100  is prohibited with the optical end  100  providing light  330  from an unchanging position at the interior of the eye  310 . Considering the limited size of the eye interior  310 , generally under about 1 inch in diameter, this provides an element of safety to the surgical procedure to be performed. For example, the instrument  300  and optical end  100  are prohibited from unintentionally reaching or disturbing the optic nerve  360  or retina  460  at the back of the eye  350  (see  FIG.  4   ). In some embodiments, the light  330  is of an enhanced distribution with a spread angle (θ) exceeding 100° (other angles are also possible (such as less than or greater than 100°. Thus, visualization for the surgeon is optimized for the procedure. Once more, this means that visualization is substantially unhindered while at the same time, freeing up a hand of the surgeon to perform other surgical tasks. 
     Continuing with reference to  FIG.  3   , a preplaced cannula  325  has been located at an offset position of the sclera  370  so as to avoid injury to more delicate lens  380 , cornea  390  or other delicate features at the front of the eye  350 . The instrument  300  may thus engage and traverse the cannula  325  to advance the sleeve  280  and optical end  100  to the illustrated position. For stabilization, an instrument handle  340  may be bent into position and other measures taken to affix the instrument  300  in place, such as the use of medical tape. 
     As indicated, the spread angle (θ) of the light  330  emitted from the optical end  100  may exceed 100°. With added reference to  FIG.  1   , for an optical thread of between about 350 micrometers and 450 micrometers, measured at the base  125 , this may be achievable by utilizing a grind manufactured taper angle (α) of between about 9° and 13°. For the optical end  100 , this would translate to a taper length (L) of between about 700 micrometers and about 850 micrometers. 
     The larger beam spread angle (θ) may be accompanied by a smooth beam distribution absent any hot center or sharp edge beam pattern. Additionally, the entire interior of the eye  310  may be comparatively brighter without any increase in luminous flux output when compared to conventional instrument output. 
     Referring now to  FIG.  4   , a partially sectional overview of the eye  350  is illustrated during a surgery facilitated by the instrument  300  and optical end  100  as shown in  FIG.  3   . In this view, a vitrectomy needle  400  is being utilized to address an eye issue such as treating a hemorrhage in a given eye region. This begins with the needle  400  being inserted through another preplaced cannula  425 . A suction may be applied and a port  477  of the needle  400  may be utilized for the uptake of blood from the hemorrhage and vitreous humor. Notice that the cannula  425  is again positioned in an offset manner at the sclera  370 . In this way, the more delicate cornea  390  and lens  380  are again avoided. By the same token, the optic nerve  360  is also quite delicate. Thus, visibility may be key to ensuring that the needle  400  does not inadvertently contact the nerve  360 , retina  460  or other delicate features at the back of the eye  350 . 
     This sought visualization is more than adequately facilitated by the instrument  300  and optical end  100  as illustrated here and detailed above. Specifically, light  330  is provided that is smooth and evenly distributed with a spread angle (θ) exceeding 100 (see  FIG.  3   ). As a result, not only is surgical performance enhanced but so too is safety in carrying out the illustrated procedure. Thus, in spite of other challenges, such as the surgeon&#39;s observation angle likely being off-center, good illumination and visualization may be provided for the procedure. 
     Referring now to  FIG.  5   , a chart is shown highlighting a targeted manufacturability window  500  for various architectures of the optical end  100  of the instrument of  FIG.  1   . In actual practice, spread angle results noted at the y-axis of the chart may vary by a degree or two from the simulated result curves illustrated by the chart of  FIG.  5   . Nevertheless, the chart and these curves may provide a useful guide in terms of seeking repeatability of expected results as a manufacturing aid. 
     Continuing with reference to  FIG.  5   , with added reference to  FIG.  1   , a fiber optic thread of between about 375 micrometers and about 425 micrometers as measured at the base  125  may be utilized. With such a thread available, and a minimum spread angle (θ) of 100° sought, the light emitting properties of different taper lengths and angles may be examined. For example, different taper angles (a) ranging from 8° to 14° are examined over different taper lengths (L). 
     Whether the taper length (L) is 0.70 mm, 0.75 mm or 0.85 mm, it is apparent that the expected spread angle (θ) will exceed 100° so long as the taper angle (α) is within the 8° to 14° range depicted. For tighter results, the manufacturer may seek to narrow the range of taper angle (α) options to a peak window  500  where greater spread angles ( 0 ) may be repeatedly observed. In the embodiment shown, for the evaluated taper lengths (L), it is apparent that a spread angle (θ) minimum of 103° degrees is attainable so long as the taper angle (α) of between about 10° and 12° is utilized. Of course, results may vary and this is only an example of how such a window  500  might be established as a manufacturing aid. 
     Referring now to  FIGS.  6 A and  6 B , flow-charts are shown illustrating embodiments of manufacturing and employing an optical end of a chandelier instrument to facilitate eye surgery. Specifically, as noted in  6 A, a taper angled end cone may be formed at the optical end of a fiber optic thread with a grinding system as detailed hereinabove (see  610 ). The architectural parameters of the optical end may be predetermined in light of tested and expected results as also described above. Regardless, upon execution of the predetermined grinding techniques utilized, the optical end may be incorporated into a chandelier instrument for eye surgery as indicated at  630 . Thus, as shown in  FIG.  6 B , the light instrument may be affixed for an eye surgery (see  650 ). This means that a spread angle in excess of 100° may be attained through the optical end at the interior of the eye during the surgery (see  670 ). As a result, as indicated at  690 , a surgical procedure may take place without requiring the surgeon to manually hold the light instrument. Further, this may occur without sacrifice to eye interior illumination. 
     Embodiments described hereinabove include tools and techniques that allow for the use of a light instrument with an optical end of unique architecture to facilitate a wide angle emission of light. Once more, the surface of the optical end may be formed or enhanced by grinding in place of conventional cutting to further enhance uniformity of distribution throughout the eye interior during surgery. 
     The preceding description has been presented with reference to presently preferred embodiments. However, other embodiments and/or features of the embodiments disclosed but not detailed hereinabove may be employed. Furthermore, persons skilled in the art and technology to which these embodiments pertain will appreciate that still other alterations and changes in the described structures and methods of operation may be practiced without meaningfully departing from the principle and scope of these embodiments. Additionally, the foregoing description should not be read as pertaining only to the precise structures described and shown in the accompanying drawings, but rather should be read as consistent with and as support for the following claims, which are to have their fullest and fairest scope.