While fragmatome remains the gold standard, in such cases the high ultrasound energy can be transmitted to the sclera, risking scleral melt, difficulty closing the sclerotomy, and hypotony with its complications. Perfluorocarbon liquid (PFCL) is another way to manage this condition by floating the lens toward the iris plane for phacoemulsification, but the phacoemulsification energy is still problematic. Also, the convex interface of PFCL means that when it is used to float a crystalline lens, the lens tends to slide toward the periphery. This can make access difficult in small pupils and may push the lens toward the vitreous base during emulsification, increasing the risk of peripheral vitreous traction and retinal breaks. There is also the expense of PFCL to consider. Another concern is that, while pupil expansion devices are available in our hospital, using them in these cases can trigger more inflammation in African eyes.
One option that has worked well for us is to adapt a familiar manual small incision cataract surgery step – the large, self-sealing scleral tunnel – and combine it with needle levitation. This avoids fragmatome use inside the vitreous cavity, as well as providing a controlled way to remove the lens.
Most cataract surgeons in Rwanda are very familiar with manual small-incision cataract surgery, and I learned the large, self-sealing scleral tunnel technique from them; it has become a useful part of my vitreoretinal toolkit.
The technique:
A superior limited peritomy is made from ten–two o’clock, with cautery applied to bleeding vessels.
An 8 mm frown-shaped scleral tunnel is fashioned, leaving the anterior chamber closed to keep the globe firm for vitrectomy.
A standard 3-port, 23-gauge pars plana vitrectomy is performed. Core vitrectomy is done, with posterior vitreous detachment (PVD) induction if absent, followed by a careful peripheral vitrectomy.
After completing the vitrectomy, the scleral tunnel is opened with a keratome.
A bent 25-gauge needle is introduced through one of the ports to gently lift the dropped crystalline lens into the anterior chamber.
Dispersive viscoelastic is used to fill the anterior chamber to protect the corneal endothelium.
The lens is delivered en bloc using a vectis through the scleral tunnel.
An internal search is performed to ensure there are no retinal breaks, which are treated with laser or cryotherapy as appropriate.
Secondary IOL implantation follows; at our centre, the default is an iris-claw lens.
The same approach has also worked effectively for other difficult cases, including large posteriorly dislocated polymethyl methacrylate (PMMA) intraocular lenses and intraocular foreign bodies that are too rigid or bulky for safe removal through sclerotomies or the cornea. In these situations, the scleral tunnel provides a secure and self-sealing exit route. It has often turned out to be the simplest and safest way forward.
The technique is practical, cost-effective, and well suited to low-resource settings like Rwanda. It avoids prolonged ultrasound in the vitreous cavity, reduces the risk of retinal breaks or hypotony, and relies on inexpensive, widely available instruments. While the fragmatome remains the gold standard where it is effective, this method has demonstrated an efficient and reliable alternative for dense lenses.
