Femtosecond cataract surgery can be performed in presence of vitreous fluid
Surgeon explains a case of dense traumatic cataract and zonular dehiscence with vitreous in the anterior chamber.
Zonular dehiscence can be due to traumatic injury from external trauma or iatrogenic trauma from previous intraocular surgery, nontraumatic causes such as pseudoexfoliation, or congenital disorders such as Marfan syndrome. Regardless of the etiology, zonular dehiscence leads to lens instability within the eye.
An unstable lens due to compromised zonules with a dense cataract poses challenges even to an experienced phaco surgeon. Such a combination increases the risk of further vitreous loss, iatrogenic corneal endothelial damage, secondary corneal edema and a dropped nucleus into the vitreous cavity, all of which can have a deleterious effect on the final visual outcome. Hence, a comprehensive pre-surgical examination, detailed surgical planning and a least traumatic surgical approach will be beneficial in dealing with such difficult cataract cases. Femtosecond laser-assisted cataract surgery helps in softening the dense cataract and performing laser capsulotomy with the least amount of lens movement and hence indirectly affords protection to the existing zonules and sustains the lens in its current resting position.
In this column, Dr. Almallah describes the surgical use of femtosecond laser-assisted cataract surgery in a case of dense traumatic cataract and zonular dehiscence with vitreous in the anterior chamber, demonstrating the beneficial use of femtosecond laser technology with an optimal outcome.
Thomas “TJ” John, MD
OSN Surgical Maneuvers Editor
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.
Omar F. Almallah
A patient presented with a 4+ grade cataract, the result of a high-velocity tennis ball injury to the left eye. The trauma caused a retinal tear, and the referring retina surgeon performed a reparative cryotherapy procedure. The injury also caused zonular rupture, which rapidly developed into a cataract.
The patient had vision of 20/25 in the non-affected right eye and 20/300 in the affected left eye. The exam indicated normal pressure. The anterior segment of the traumatic eye showed vitreous fluid at 3 o’clock and 9 o’clock with phacodonesis, making the lens shift vertically with ocular movement. The vitreous came around the edge of the pupil to create an oval shape in the horizontal dimension; fluid in the 12 o’clock and 6 o’clock area of the pupil prevented full dilation. The cornea was clear, with no signs of rupture in the cornea or globe. The patient dilated to only 6 mm, but this allowed me to view the macula. A topographical scan indicated considerable with-the-rule astigmatism of 2.5 D (Figure 1). I estimated the patient had 3 to 4 clock hours of zonular rupture nasally and temporally.
Images: Almallah OF
The challenge: Remove the cataract
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.
In the operating room, I proceeded by dilating the pupil maximally, breaking the synchysis superiorly and administering unpreserved epinephrine to help dilate the pupil a little bit more with a lidocaine mixture. The pupil dilated enough to perform an uneventful femto procedure.
Upon making the incision, more vitreous came out. I applied a small amount of viscoelastic; however, this was ineffective at stopping the fluid, and I could see that the lens was unstable. I easily removed the free-floating capsular remnant and inserted a capsular tension ring. I performed hydrodissection and rocked the lens a little bit to remove the air bubbles and stabilize the lens. Using Triesence (triamcinolone acetonide injectable suspension, Alcon) to stain the vitreous that was not in the anterior chamber, I performed a limited anterior vitrectomy to remove the vitreous from the pupil area and was able to clear my working area despite the continuous flow of vitreous (Figure 2).
I then proceeded with a very gentle phaco setting to create the grid pattern. I emulsified the cataract as much as possible and sculpted all the way into the bag without any cracking. With the peristaltic pump, I turned the 45° tip superiorly to occlude the lens material at the unsoftened peripheral edge. As the fragments began moving, I applied just enough phaco energy to break the rim, permitting the material to quickly flow into my tip without unnecessary manipulation. I left a small amount of vitreous fluid, primarily nasally.
To correct the 2.5 D astigmatism, I inserted a 4 D cylinder toric lens (ZCT400, AMO), rotated it to match up with the with-the-rule cylinder, let it unfold and sutured it, all without complication (Figure 3).
At 1 day postoperative, the patient’s vision was 20/30 uncorrected with a final prescription of +0.5, +0.5 at 180 and 20/20 vision (Figure 4). His pupil remained atonic, and he had multiple sphincter ruptures caused by the trauma. As a result, the patient experienced glare and night halos because of the enlarged pupil. The patient opted not to undergo any additional intraocular procedures, such as a pupillary cerclage to reduce the pupil size. However, after 6 months, the lens continued to hold stable, and the patient was scheduled for PRK to improve vision in both eyes.
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Alió JL, et al. J Refract Surg. 2014;doi:10.3928/1081597X-20140516-01.
Chee SP, et al. Am J Ophthalmol. 2015;doi:10.1016/j.ajo.2015.01.016.
Chen M, et al. Int J Ophthalmol. 2015;doi:10.3980/j.issn.2222-3959.2015.01.34.
Georgopoulos GT, et al. Acta Ophthalmol Scand. 2007;doi:10.1111/j.1600-0420.2007.00901.x.
For more information:Omar F. Almallah, MD, FACS, FABES, can be reached at Susskind & Almallah Eye Associates, 20 Mule Road, Toms River, NJ 08755; email: firstname.lastname@example.org.
Thomas “TJ” John, MD, is a clinical associate professor at Loyola University at Chicago and is in private practice in Oak Brook, Tinley Park and Oak Lawn, Ill. He can be reached at email: email@example.com.
Disclosures: Almallah and John report no relevant financial disclosures.