This column is one in an invited series by Dr. Osher. The series highlights techniques that may be helpful in particular to young practitioners.
There are multiple types of cataracts that fall under the category of “white,” and it is important to differentiate because each behaves differently. Moreover, the surgical approach is very different. Let us begin this column by classifying white cataracts as nuclear/cortical, intumescent, or Morgagnian.
This is the easiest white cataract to deal with because it represents nuclear sclerosis and/or cortical opacification. Visualization is key, and the anterior capsule should be stained with trypan blue. A confluent white cortex may be adherent to the capsule, so an effective hydrodissection is important. It may be necessary to liberate recalcitrant corticocapsular adhesions by viscodissection with a cohesive ophthalmic viscosurgical device (OVD). The surgeon should expect this case to go smoothly.
This is the white cataract with the most potential for a surgical complication. It is usually present in a younger patient, and the anterior cortex has a “frothy” appearance. The slit beam will show a “flare” as it passes through the anterior cortex, and the examiner can expect diagnostic testing to reveal a lens thickness over 5 mm. This is the cataract which is associated with the feared Argentinian flag sign first reported by Perrone and Albertazzi from Argentina.1
The best article which discusses this cataract was written by Figueiredo in 2012 in which a brilliant explanation for the Argentinian flag was proposed.2 Dr. Figueiredo hypothesized that a relative nuclear block creates a separate anterior and posterior cortical compartment. As the cortex becomes hydrated, the entire lens develops an increased intralenticular pressure. However, each compartment also has a separate increased pressure which would explain why simple decompression of the anterior cortex could still result in an Argentinian flag sign as the nucleus is pushed forward causing the opening in the anterior capsule to extend peripherally toward the equator. The key maneuver after decompressing the anterior compartment is to push the nucleus back toward the posterior capsule breaking the relative block and decompressing the posterior cortical compartment (Video 1, https://links.lww.com/JRS/A691). Once this is accomplished, the remainder of the surgery becomes uneventful.
Let us summarize the key steps in managing the intumescent cataract: (1) Stain the anterior capsule with trypan blue. (2) Inject a retentive OVD flattening the lens capsule and overcoming the gradient produced by increased intralenticular pressure. (3) Puncture the anterior capsule which releases the pressure in the anterior cortical compartment, then continuing to ballot the nucleus posteriorly, which effectively decompresses the posterior cortical compartment. Dr. Figueiredo called this “posterior voiding.” (4) A smaller capsulorhexis will not tend to run along the anterior lens bow toward the periphery, and it can be safely enlarged if necessary at a later time.
By following these recommendations, the Argentinian flag can be confined to Latin America!
This cataract develops because of chronic liquefaction of the cortex. The milky cortex completely surrounds a hard, ball bearing-like nucleus, which usually sinks with gravity into the inferior capsular bag. The challenge of a completely liquefied cortex is the collapse of the capsular bag after the milky cortical fluid has escaped into the anterior chamber once the anterior capsule is punctured. The surgeon should refill the capsular bag by injecting an OVD, widely separating the anterior from the posterior capsule (Video 2, https://links.lww.com/JRS/A692). Otherwise, it is possible to tear the posterior capsule while performing the anterior capsulorhexis. Again, visualization is critical, so the procedure begins by staining the anterior capsule with trypan blue. This dye has been reported to make the anterior capsule more brittle as reported separately by Dr. Ehud Assia from Israel and published by Dr. Burkhard Dick from Germany.3 Dr. Minu Mathen from India has suggested that this tendency toward a brittle capsule can be minimized by washing out the diluted dye quickly.4 Next, Healon 5 (my preference) is injected into the anterior chamber and into the capsular bag. The capsulorhexis is more difficult to perform when there is no underlying cortical support, so a forceps rather than a needle may be necessary. After the capsulorhexis has been completed, the surgeon can look forward to a longer emulsification, given the hardness of the nucleus. Extra caution is necessary because there is no posterior cortical plate to protect the posterior capsule. The posterior capsule may have a fibrotic plaque, given the longstanding presence of this cataract. If an edge can be elevated, the plaque can be dissected off the posterior capsule with an intraocular forceps or the surgeon may leave the capsule alone for a subsequent YAG laser posterior capsulotomy.
All 3 white cataracts share in common the necessity of using a capsular dye and the size of the rhexis should be created with the possibility in mind that optic capture may be required. Successful surgery is always satisfying for the surgeon and may represent a life-changing gift to the patient who has suffered with a white cataract.
1. Perrone D, Albertazzi R. Argentina flag sign. Video J Cataract Refract Surg 2001;XVII
2. Figueiredo CG, Figueiredo J, Figueiredo GB. Brazilian technique for prevention of the Argentinean flag sign in white cataract. J Cataract Refract Surg 2012;38:1532–1536
3. Dick HB, Aliyeva SE, Hengerer F. Effect of trypan blue on the elasticity of the human anterior lens capsule. J Cataract Refract Surg 2008;34:1367–1373
4. Mathen M. Morgagnian. Video J Cataract Refract Glaucoma Surg 2020;36