Healio
Healio
Issue: May 1, 2006
ByAmar Agarwal, MS, FRCS, FRCOphth
May 01, 2006
5 min read
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Technique helps remove lens fragments that have fallen into the vitreous

If the surgeon is not careful when removing the fragments, retinal complications could occur.

Issue: May 1, 2006
ByAmar Agarwal, MS, FRCS, FRCOphth
Complications Consult [logo]

Dislocation of lens fragments into the vitreous cavity occurs in a small percentage of cases of cataract extraction with phacoemulsification with potentially serious consequences. Small lens fragments consisting of mostly cortical material may gradually resolve with conservative medical management alone. However, large lens fragments with a sizeable nuclear component do not resolve easily and may elicit a phacoantigenic response from the host.

Responsibility of cataract surgeon

Amar Agarwal, MS, FRCS, FRCOphth [photo]
Amar Agarwal

In the event of a rupture of the posterior lens capsule or zonular dehiscence leading to posterior migration of lens fragments, the cataract surgeon must avoid any uncontrolled, forceful surgical maneuvers in the vitreous cavity in an attempt to retrieve the sinking lens fragments. Any retrieval technique that does not provide for the appropriate management of the vitreous creates the potential of immediate or subsequent retinal complications. Thus, the cataract surgeon must refrain from the temptation of passing a sharp instrument or lens loop into the mid or posterior vitreous cavity to engage the sinking lens fragments or passing forceful irrigation fluid into the vitreous cavity to float the lens fragments. Such maneuvers usually generate vitreoretinal traction resulting in retinal breaks and detachment. Instead, the surgeon should finish the cleanup of the remaining cortical debris within the capsular bag and its vicinity and then perform a limited anterior vitrectomy in the event of vitreous prolapse into the anterior chamber and at the cataract wound. The patient can be referred to a vitreoretinal surgeon to manage the case.

FAVIT technique

We described the FAVIT technique in 1999 and have modified it subsequently. FAVIT stands for fallen vitreous, meaning a technique to remove fragments that have fallen into the vitreous. This technique removes dropped nuclei in a safe manner. Visualization is preferably done with a chandelier illumination in which xenon light is attached to the infusion cannula. We use the Synergetics photon machine. This gives excellent illumination and one can perform a proper bimanual vitrectomy, as it is not necessary for the surgeon to hold an endoilluminator in his hand. A reinverter system has to be used with a Volk wide-field lens. The Volk SuperMacula lens helps give better stereopsis.

When we use the wide-field indirect contact vitrectomy lenses we have to use a reinverter, as the image is seen inverted. The reinverter makes the image erect so that the surgeon does not have difficulty in operating. We use the one from Zeiss, which has a foot-switch connection. On pressing the foot-switch button, the reinverter works. The Volk Reinverting Operating Lens System is also present. It has a unique single-element prism design. This installs in the Zeiss and other microscopes.

Surgical technique

In the technique, an infusion cannula is fixated through the first port. We use the chandelier illumination system with a light source attached to the infusion cannula. An endoilluminator is then inserted through the second port, and a vitrectomy probe is inserted through the third port. All three ports are through the pars plana. The surgeon performs a thorough posterior vitrectomy, including the elimination of the vitreous fibers surrounding the retained lens fragments in order to prevent subsequent vitreoretinal traction. After the completion of the posterior vitrectomy, the surgeon replaces the vitrectomy probe with a phaco needle through the same incision. We use the microphakonit 0.7-mm needle. In the nondominant hand, the surgeon can hold either an endoilluminator or a vitrectomy probe. When using the chandelier illumination system, the surgeon will be able to visualize the fundus even without an endoilluminator.

With the ultrasonic power at 50% and the aspiration intensity at moderate setting, the surgeon activates the suction-only mode to elevate the lens fragment from the retinal surface. A small burst of ultrasonic energy is applied to embed the probe tip into the elevated lens fragment, and then the entire fragment is lifted anteriorly. The instrument in the nondominant hand is used at the same time to guide the lens fragment above the iris plane and into the anterior chamber. Finally, the lens fragment is gradually removed with continuous phacoemulsification in the anterior chamber without pulsing or chopping to avoid dropping small fragments back into the vitreous cavity. A large or hard nuclear fragment may be removed through an enlarged limbal incision.


Nucleus lying on the retina. Notice the wide-field view of the retina. This is because of the wide-field contact lens being used and the chandelier illumination, which is seen in the upper right-hand corner.


FAVIT technique. After completing the vitrectomy, one hand holds the phaco probe with the needle and the other hand can hold a vitrectomy probe (as seen in the figure) or an endoilluminator. The chandelier illumination helps give light for one to see without an endoilluminator (as seen in the figure).


Suction-only mode is activated to elevate the lens fragment, and the phaco tip is then embedded into the elevated lens fragment with a small burst of ultrasonic energy. It is better to use a microphakonit 0.7-mm needle. The nucleus is then lifted anteriorly.


Combination of perfluorocarbon liquid and FAVIT. Perfluorocarbon liquid is injected once vitrectomy is done. Then, using the phaco needle, the nuclear pieces are removed.

Images: Agarwal A

Perfluorocarbon liquids

The surgeon can also use a combination of perfluorocarbon liquids and FAVIT. Once vitrectomy is done, perfluorocarbon liquid is injected to raise the nuclear fragments from the retina. Then, using the phaco needle, they are removed. Retinal breaks and peripheral retinal detachment discovered during the inspection are then promptly treated with the appropriate modality (eg, laser, cryotherapy, scleral buckling, or fluid-air or fluid-gas exchange). Residual perfluorocarbon liquid is removed before closure. A small amount of perfluorocarbon liquid may be infused on the retinal surface to protect it from dropped lens fragments during the process of lens emulsification. Excessive volume of perfluorocarbon is avoided to decrease the propensity of peripheral displacement of the floating lens fragments toward the vitreous base due to the convex meniscus of the perfluorocarbon. During phacoemulsification, the ultrasonic power of the phaco probe is kept at a low to medium setting to reduce the tendency of blowing the lens fragments from the phaco tip toward the retina.

Key points

In the event of a rupture of the posterior lens capsule or zonular dehiscence leading to posterior migration of lens fragments, the cataract surgeon must avoid any uncontrolled and forceful surgical maneuvers in the vitreous cavity in an attempt to retrieve the sinking lens fragments.

In case of familiarity with vitreoretinal techniques, one may convert to a posterior segment setup and use one of the methods described for removing the lens fragments. Otherwise, a prompt referral of the patient to a vitreoretinal surgeon is recommended.

Medical management with topical anti-inflammatory, antibiotic and cycloplegic medications should be instituted. If necessary, hypotensive agents can also be used.

Chandelier illumination is a good method for visualization when trying to remove dropped nuclei.

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