Sunday, October 02, 2005

Chapter 3 - Staining the Lens Capsule

The white cataract used to be one of the most difficult surgeries to do. Capsular staining, however, has changed these cases from complex to routine. Capsular stains (e.g., indocyanine green and trypan blue) are useful whenever the capsule is hard to see, for instance:

  • Classic white cataract
  • Traumatic cataract with possible anterior capsular tear
  • Dark red or brown cataract with limited red reflex
  • Started rhexis and then lost capsule in an area of cortical spokes or dense portion of cataract

Indocyanine Green (ICG)

reference: Horiguchi M, Miyake K, Ohta I, Ito Y. Staining of the lens capsule for circular continuous capsulorrhexis in eyes with white cataract. Arch Ophthalmol. 1998 Apr;116(4):535-7. [PUBMED]

  • ICG is used to stain the lens capsule
  • The ICG is washed out with OVD
  • Leaving the anterior capsule green in contrast to the white cataract
  • CCC is performed in the usual fashion but easily visualized
  • Useful for delineating anterior capsular trauma
  • Stain in the vitreous may be toxic to the retina so use the least amount possible
  • Preparation:

    • Draw up 0.5 cc of aqueous solvent (comes with ICG) into syringe
    • Place aqueous solvent into vial of 25 mg ICG and shake
    • Draw up 4.5 cc of BSS into syringe
    • Place BSS (original article was BSS ; but BSS OK) into ICG vial and shake some more
    • Osmolarity is 270 (plasma 285)
    • Final concentration is 0.5%

Trypan Blue (Vision Blue)

  • Approved by the FDA for capsular staining in winter 2005
  • Cheaper, better, faster
  • Already mixed for capsular staining

Surgical Technique for either stain

  • Place paracentesis
  • Fill anterior chamber with air
  • Can place some dispersive OVD at wound if air leaks
  • Drop/rub ICG solution or Trypan Blue onto anterior capsule with cannula
  • Fill anterior capsule with OVD
  • Make typical wound into anterior chamber
  • Perform CCC (capsule will be green or blue, lens will not)



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