Poor Red Reflex
As discussed in Chapter 8, creation of a continuous curvilinear capsulorrhexis (CCC) is a key component of safe phacoemulsification. An abnormal red reflex makes it difficult for the surgeon to discriminate the capsular edge, thus increasing the risk of an incomplete or errant capsulorrhexis. In an eye with dense brunescent or cortical cataract, the capsule is prone to radial tears. The tears result from vaulting of the anterior capsule, caused by increased lens thickness and cortical hydration. Corneal scars compromise the surgeon’s view of the capsule and make intraocular manipulation treacherous. These challenges can be addressed by staining the capsule with trypan blue (Fig 12-6).
Prior to capsulotomy, AC fluid can be replaced with air, and a small amount of OVD can be used to occlude the paracentesis site. Alternatively, a high-viscosity OVD can be instilled to fill approximately two-thirds of the anterior chamber. The surgeon then injects trypan blue through a 27-gauge blunt cannula, starting as far away from the paracentesis incision as possible to deliver the dye directly to the capsule. In the presence of a healthy endothelium, the trypan blue can be injected without prior air or viscoelastic injection. Usually, the dye is then rinsed from the AC with balanced salt solution and replaced with a high-viscosity OVD, under which the stained anterior capsule is easily visible. The high-viscosity OVD exerts pressure on the anterior capsule, maintaining chamber depth and flattening the capsule to prevent radial extension of the capsular tear. A CCC is then created (Video 12-2).
Figure 12-6 The anterior capsule is stained lightly with trypan blue, thereby aiding visualization of the capsule during creation of a capsulorrhexis. This technique is helpful in eyes with dense brunescent or cortical cataracts that interfere with the red reflex.
(Courtesy of Lisa Rosenberg, MD.)
Capsule staining with trypan blue dye. Courtesy of Lisa Park, MD.
Jacobs DS, Cox TA, Wagoner MD, Ariyasu RG, Karp CL; American Academy of Ophthalmology; Ophthalmic Technology Assessment Committee Anterior Segment Panel. Capsule staining as an adjunct to cataract surgery: a report from the American Academy of Ophthalmology. Ophthalmology. 2006;113(4):707–713.
Excerpted from BCSC 2020-2021 series: Section 11 - Lens and Cataract. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.