Frequently asked questions

  1. Is it safe to perform a PPCCC?
  2. How stable does the calliper ring remain on top of the anterior capsule?
  3. Why is it not advised to fill the capsular bag prior to perform a PPCCC?
  4. How can one easily define the anterior from the posterior haptic?
  5. How can the bag-in-the-lens be stabilised once injected in the anterior chamber?
  6. What is the degree of tolerance for the size of the ACCC and PPCCC?
  7. Can the lens be implanted in case of weak zonular fibers?
  8. Is it safe to perform a PPCCC in a high myopic eye?
  9. Which are the indications for CTR implantation using the BIL technique?
  10. Is the surgical time increased due to the supplementary step of PPCCC?
  1. Is it safe to perform a PPCCC?

    This question has been answered in the literature by many authors and research groups. However, we conducted a clinical study by measuring the fluorescein concentration in the anterior vitreous by means of fluorophotometry after cataract surgery, with and without PPCCC. The results of this study showed no increase in fluorescein in the anterior vitreous provided the anterior hyaloid remained intact.

    A Shows identical fluorescein concentration in the anterior vitreous in the eyes with PPCCC than without PPCCC (Control) (0’ – 1’ – 10’ – 30’ – 45’ – 60’).

    B Shows highly increased fluorescein concentrations in the anterior vitreous in the eys with complicated cataract cases compared to the controls.

    Literature: V. De Groot, M. Hubert, J.A. Van Best, S. Engelen, S. Van Aelst, M.J. Tassignon (2003). Lack of fluorophotometric evidence of aqueous-vitreous barrier disruption after posterior capsulorhexis. J. Cataract Refract. Surg. 29, 2330-2338 A. Galand, F. van Cauwenberge, J. Moosavi (1996). Posterior capsulorhexis in adult eyes with intact and clear capsules. J. Cataract Refract. Surg. 22, 458-461 E. Stifter, R. Menapace, K. Kriechbaum, L. Vock, A. Luksch (2009). Effect of primary posterior continuous curvilinear capsulorhexis with and without posterior optic buttonholing on postoperative anterior chamber flare.

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  2. How stable does the calliper ring remain on top of the anterior capsule?

    In the bag-in-the-lens technique, the balance in pressure between anterior and posterior segment is crucial. The ring calliper is stabilised simply by pressurising the anterior chamber by means of OVD. The OVD which I prefer for this purpose is Healon GV (AMO, Abbott Medical Optics). I do not use Healon V, even not in children or babies. The OVD in the anterior chamber has two functions:

    • protection of the endothelium.
    • counteracting the positive vitreous pressure after having performed the corneal incision and before starting any manipulation in the anterior segment.

    Because in the BIL procedure, the balance of the eye is optimally respected throughout surgery, inflammation will also be very low.
    The next question could be:
    When is the anterior chamber properly filled with OVD? The answer is: As soon as you observe a reflux of OVD from the incision wound.
    DVD nr. 8

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  3. Why is it not advised to fill the capsular bag prior to perform a PPCCC?

    When performing a PPCCC, it is again very important to respect the pressure balance between anterior and posterior capsule. In case of overpressuring the anterior chamber, the posterior capsule will be pushed in close contact to the anterior hyaloid. This will increase the risk of puncturing the anterior hyaloid. In addition, the risk for capsule zipping while performing a PPCCC is much higher in the presence of a concave positioned posterior capsule compared to a horizontally positioned capsule.

    In case of underpressure of the anterior chamber, the vitreous will move forward and the posterior capsule will be slightly convex. This situation is extremely dangerous for uncontrolled enlargement of the posterior capsule puncture performed for the injection of OVD in the space of BERGER.

    After having emptied the capsular bag of all lens material...
    ... NEVER re-fill the capsular bag with OVD !!
    ... on the contrary ONLY fill the anterior chamber with OVD on top of the anterior capsule and bring the capsule in a horizontal plane.
    ... after puncturing the posterior capsule inject the OVD through the hole until the blister is slightly larger than ...
    ... the ACCC. Perform then the PPCCC of the same size than the ACCC.

    What you have to remember, is:

    • as soon as the capsular bag has been emptied from any lens material: refill the anterior chamber by injecting the OVD on top of the anterior capsule.
    • keep both anterior capsules close to each other.
    • puncture the posterior capsule in the middle of the area of the overlying anterior capsulorhexis.
    • use a microforceps to perform a well-controlled PCCC.

    DVD nr. 8

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  4. How can one easily define the anterior from the posterior haptic?

    If the posterior haptic is positioned vertically in the cartridge, this haptic will be horizontal once inserted and unfolded in the anterior segment of the eye.
    The opposite will happen in case the posterior haptic is positioned horizontally.
    In future, preloaded cartridges will be available in order to avoid any confusion. To inject the BIL in the correct orientation will be particularly important when dealing with toric lenses since the toric component is located at one side of the bag-in-the-lens optic and preferentially oriented facing the cornea.
    DVD nr. 9

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  5. How can the bag-in-the-lens be stabilised once injected in the anterior chamber?

    Stabilisation of the lens once injected in the anterior chamber is again crucial and will allow a smooth and easy implantation.

    By using the OVD needle (Healon regular or GV), the lens can be positioned so that the posterior haptic is acceptably horizontal, facing both capsulorhexis openings. It then can be pushed in close contact to the anterior capsule by injecting some more OVD on top of the anterior face of the lens optic.

    By using the OVD needle the lens is then displayed slightly to the right in order to position the posterior left haptic under the posterior capsule at the left side and by pushing very smoothly at the superior and inferior border of the optic, the capsules will automatically glide into the lens groove.
    DVD Nr. 2-3

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  6. What is the degree of tolerance for the size of the ACCC and PPCCC?

    In adult eyes, the degree of tolerance is larger than in children or in babies. At least one of both rhexes should have the correct sizing which is between 4.5 to 5 mm. The bag-in-thelens can still be implanted in case one capsulorhexis, whether it is the anterior or the posterior one, is too large, provided the other one has the proper sizing.
    Unproper sizing may occur in case of:

    • inadvertent oversizing
    • IOL exchange in which case the anterior capsulorhexis is oversized. It is then mandatory to carefully size the posterior capsulorhexis.
    • IOL exchange in the presence of a large YAG laser capsulotomy. In this case the anterior capsulorhexis, measured by means of the calliper ring, should be of the proper sizing.

    Too small anterior and posterior capsulorhexes should be avoided. This will make the implantation very difficult. The pressure needed to implant the lens will be too high causing an enormous stress on the zonular fibers.
    DVD Nr. 29

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  7. Can the lens be implanted in case of weak zonular fibers?

    Yes, the lens can be implanted in case of weak zonular fibers, taking the following points into account:

    1. The use of a capsule tension ring, which should be positioned after the I/A of the cortex remnants.
    2. A bimanual implantation technique is used: one hand retracts both capsules while the other hand keeps the lens in place.

    While in the normal BIL implantation the capsule remains stable and the lens is manipulated to be properly positioned, in case of weak zonular fibers, the capsule is manipulated using a bimanual technique in order to glide the capsule into a stabilised BIL.
    DVD Nr. 10-11

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  8. Is it safe to perform a PPCCC in a high myopic eye?

    Our clinical experience allows to conclude that it is safe to perform a PPCCC in a high myopic eye. The rate of retinal detachment is the same in our series than in the literature (publication in preparation). However, we always insert a capsule tension ring (CTR) in eyes presenting an axial length of 26 mm or more. The rationale behind this relies on the clinical evidence that these eyes often present an anterior vitreous schisis with a very large Berger’s space and as a consequence a very weak anterior vitreous support. We believe that by stabilising the capsule with a CTR, this will be beneficial for the stability of the anterior vitreo-capsular interface.

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  9. Which are the indications for CTR implantation using the BIL technique?

    There are two indications for CTR use:

    1. in case of weak zonules
    2. in case of axial length ≥ 26 mm

    DVD nr. 1 – DVD nr. 14

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  10. Is the surgical time increased due to the supplementary step of PPCCC?

    Once the learning curve is terminated, surgical time is increased of about half a minute compared to a procedure without PPCCC. A routined surgeon will perform a routine BIL case in 11 to 12 minutes. My fellows perform the surgery in 16 to 17 minutes.

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