This article is more than 5 years old. Information may no longer be current.
Retinal surgeon explains how to handle dropped nucleus
Anterior segment methods have high risk of retinal detachment, whereas pars plana vitrectomy provides space for safer, more effective techniques.
Click Here to Manage Email Alerts
A dropped nucleus can be effectively handled to avoid the risk of retinal damage, according to one surgeon.
Oliver Zeitz, MD, gave pearls at the Euretina meeting in Vienna, Austria, on how to deal with this complication in the best way, “from the point of view of a retinal surgeon.”
His first recommendation was to avoid this complication, which is often caused by surgical errors because of poor concentration at some crucial stage of the cataract procedure. If the complication occurs, removing the dropped lens material is mandatory because inflammation and secondary glaucoma will otherwise occur.
There are two approaches to treating a dropped nucleus: the anterior segment approaches and the pars plana vitrectomy approaches, he said.
Anterior segment approaches encompass techniques such as the visco trap, in which the dropping nucleus is caught in a bed of viscoelastic placed in the vitreous cavity, and posterior assisted levitation, in which a hook-like instrument is inserted in the posterior segment to lift the dropped nucleus mechanically.
“A drawback of these anterior segment approaches is that there is a risk of uncontrolled vitreous traction with subsequent retinal tears and retinal detachment,” Dr. Zeitz said.
The rate of retinal detachment is high in these cases, ranging between 10% and 26%.
From the point of view of a posterior segment surgeon, he said pars plana vitrectomy is a more efficient and safer approach.
“If we remove the vitreous, the lens can be removed by vitrectome or fragmentome. However, to take advantage of this technique, it is mandatory to keep a safe distance from the retina,” Dr. Zeitz said.
Compared with an anterior segment approach, the retinal detachment rate with pars plana vitrectomy ranges up to 9%.
 After pars plana vitrectomy, the lens can be removed by using a vitrectome or a fragmentome. It is mandatory to keep a safe distance from the retina. |
 Safer removal of the dropped nucleus can be accomplished by inserting heavy liquids and performing the removal maneuvers as anterior as possible. |
A safe surgical strategy
To minimize the risk of detachment, an appropriate surgical strategy must be adopted.
“First, it’s important to do the removal of the lens distant from the retina, preferably away from the posterior pole,” Dr. Zeitz said.
This can be accomplished with the help of the phaco instruments, aspirating the lens and bringing it up to the pupil. However, this maneuver may lead to dropping the nucleus again, and because the patient is lying on his back, there is a high risk that lens material drops right on the macula, he said.
Therefore, it may be helpful to use heavy liquids as a cushion to protect the retina while the rescuing maneuvers are performed.
“If you insert a bubble of heavy liquid into the vitreous body, the lens fragments will swim on it, and you will be able to remove the lens fragments very anteriorly,” Dr. Zeitz said.
Soft material may be removed with the vitrectome; hard lens material may be emulsified with the phaco machine.
To enhance safety and control, the dropped nucleus can be lifted completely up to the pupil, and the anterior segment access tunnel can be used to remove the lens fragments.
Dr. Zeitz said to be sure that the vitreous is completely removed.
“Don’t forget to induce a posterior vitreous detachment if that doesn’t occur spontaneously, and also mind the anterior vitreous, which frequently causes tractions on the peripheral retina,” he said.
 Anterior segment access may be used for safe removal of elevated lens fragments. |
The best time to act
Surgeons have different opinions on the best time for dealing with this complication and for implanting the IOL after it. Recommendations in the literature vary from acting immediately as it occurs to waiting a few days or a few weeks.
“There are pros and cons with all these options. If you do it immediately, the patient won’t need to come back a second time, and the risk of inflammation and secondary glaucoma will be avoided, but the anesthesia may not be adequate,” Dr. Zeitz said. “If you wait a few days, you can plan the operation better, but corneal edema might limit the view. If you wait a few weeks, the corneal edema will be reabsorbed, but there will be an increased risk of secondary glaucoma.”
His recommendation was to leave the patient aphakic, send him to the retinal surgeon and prevent the onset of glaucoma by administering acetazolamide postoperatively for 1 day.
“Don’t worry if the patient is aphakic for a couple of weeks or even a couple of months. There are easy ways to restore refraction, like a contact lens, and an IOL can be easily implanted later,” he said. – by Michela Cimberle
- Oliver Zeitz, MD, can be reached at Universitätsklinikum Hamburg-Eppendorf, Klinik und Poliklinik für Augenheilkunde, Martintstrasse 52, D-20246 Hamburg, Germany; e-mail: zeitz@uke.uni-hamburg.de.