Dr. Omar F. Almallah, an internationally recognized refractive ocular surgeon at Susskind & Almallah Eye Associates in Toms River, New Jersey, recently wrote an opinion article regarding the beneficial use of femtosecond laser-assisted cataract surgery in a particular case of a patient with dense traumatic cataract and zonular dehiscence with vitreous in the anterior chamber. The article is entitled “Femtosecond cataract surgery can be performed in presence of vitreous fluid” and was published online in the Ocular Surgery News U.S. Edition.
Femtosecond laser cataract surgery is a promising technique that was designed to assist or replace several elements of manual cataract surgery, namely the surgical incisions in the cornea and the fragmentation of the clouded lens (cataract) in the eye.
Zonular dehiscence is a condition that leads to instability in the eye. It can be caused by traumatic injury, like an external trauma or trauma during intraocular surgery, and also by non-traumatic events such as congenital disorders.
Dr. Almallah attended a patient who had an injury in the left eye due to trauma with a high-velocity tennis ball, presenting a 4+ grade cataract, the highest grade where more than 90% of the pupil and more than 50% of the back surface of the lens is obscured by the cataract. The patient had vision 20/300 in the injured eye and the trauma had caused a retinal tear for which the patient underwent a reparative cryotherapy procedure. At the time of the trauma, a zonular rupture was also caused that rapidly developed into a cataract.
The patient had normal eye pressure and the cornea had no signs of rupture. The anterior segment of the injured eye had vitreous fluid with phacodonesis (vibration of the lens with eye movement) and the patient had astigmatism, an optical defect characterized by blurred vision.
To repair the condition of a dense cataract combined with an unstable lens is a challenge, as there is an increased risk for further vitreous loss (the gelatinous mass between the lens and the retina lining the back of the eye), a dropped nucleus into the vitreous cavity, iatrogenic corneal endothelial damage and secondary corneal edema.
“Removing the cataract before losing the anterior chamber pressure and dropping the lens was a concern. I determined that the least traumatic way to get the cataract out was to avoid making any large incisions and to soften the lens using the Catalys femtosecond laser (Abbott Medical Optics). However, there was a considerable amount of vitreous in the anterior chamber, and I was not sure how the laser would behave through the vitreous. Because the fluid is a clear medium, I surmised that the laser would function as intended,” explained Dr. Almallah.
Dr. Almallah dilated the patient’s pupil and performed a femtosecond laser-assisted cataract surgery to soften the dense cataract followed by laser capsulotomy removing the free-floating capsular remnant of the unstable lens and inserting a capsular tension ring with the least amount of lens movement. Vitrectomy was performed to remove the vitreous that had flowed into the pupil area outside the anterior chamber. Astigmatism was corrected with a 4 D cylinder toric lens (ZCT400, AMO) without complications.
One day after surgery the patient’s vision was 20/30 uncorrected in the injured eye, the pupil was atonic and the patient had multiple sphincter ruptures related to trauma that caused vision with glare and night halos due to the enlarged pupil. The patient decided not to undergo additional intraocular procedures at the time to decrease pupil size. The lens was still stable six months after surgery and the patient opted to perform photorefractive keratectomy (PRK) to improve vision in both eyes.
“Femtosecond laser technology is a powerful tool for surgeons and can assist in performing procedures that require extreme delicacy in the most complex of cases. Utilization of the femto laser allowed me to successfully execute a difficult procedure using far less manipulation than a manual procedure and avoid imposing additional trauma to the patient’s eye,” concluded Dr. Almallah.