Capsulorhexis was pioneered and popularized by Howard Gimbel. Capsulorhexis is probably the most challenging to learn in cataract surgery, in other words, once a good rhexis is done half the battle is won. All the Post- Graduates and beginners struggle to do rhexis. This article has compiled small tips and tricks to do rhexis better.
Ideally, rhexis should be continuous and curvilinear i.e Circular, Central & of Correct size (5.5-6 mm).
- Circular: for proper IOL centering and stabilization in the bag
- Continous: to prevent rhexis extension
- Correct size: for IOL centering and to ensure anterior capsule overlapping IOL optic 360 degrees.
It can be done with the help of a double bent 26 G/27 G needle or rhexis forceps.
Let's break the table and use the advantages of a needle
Small diameter, lightweight
Can be done through side port so less chance of AC shallowing
Less precise control
With a needle, it is difficult to bring rhexis margin back in case of extension
Risk of inadvertent capsule nick/tear
The sharp end of the needle can cause wound damage during insertion or removal.
Bulky vs needle
Sudden movements can cause rhexis damage
Needs bigger entry port, needs to be done through main port so risk of repeated AC shallowing
- Cheap, Disposable, Universally available
- Small diameter, lightweight
- Can be done through side port so less chance of AC shallowing
- Less precise control
- With the needle, it is difficult to bring rhexis margin back in case of extension
- Risk of inadvertent capsule nick/tear
- The sharp end of the needle can cause wound damage during insertion or removal.
- Precise control
- Bulky vs needle
- Sudden movements can cause rhexis damage
- Needs bigger entry port, needs to be done through the main port so the risk of repeated AC shallowing
Prerequisites of doing rhexis
- Clear media: Clear cornea, well-dilated pupil
- Put viscoelastic over the cornea for better visibility.
- Should be done at higher magnification.
- Fill the chamber with viscoelastic.
- Try moving the eye around to get the best possible red reflex.
- Globe should be well stabilized while doing the procedure.
Tips to achieve ideal capsulorhexis:
Tip No.1 Practice Practice Practice…..
- The surgeon should have stable hands and practice fine intraocular micro-movements. Stereoscopic viewing with proper depth perception is essential.
- Theoretical concepts about physics behind tearing and shearing forces, which are in play during the rhexis process, should be read and well understood
- You can practice rhexis on the plastic film of lens box or use poached tomatoes or potatoes.
Tip No. 2 Keep Anterior chamber deep
- Use a softshell technique to deepen the AC and make the anterior capsule flat.
- Use the side port for all your maneuvers, it prevents leakage of viscoelastic.
- Avoid undue pressure on the eyeball
- Keep refilling viscoelastic as and when required
Tip No. 3 Don’t limit yourself to one technique
One should be well versed with cystitome and Utrata forceps.
You might have to use either one or combination of both depending on the situation
Tip No. 4 Proper visualization
- Use trypan blue dye to stain the anterior capsule and improve visualization.
- Increasing the magnification, “you see well-you do well”. Higher magnification also improves visualization and can help you in early identification of extension.
- Retro-illumination is one of the greatest tools available to us in the microscope. It makes use of coaxial illumination to increase the Red Glow.
- Proper patient positioning is also a measure to improve red reflex when the iris lens diaphragm is parallel to the ground the red improve as the microscope becomes coaxial and one has a good red glow
Tip No. 5 Always keep the Flap flat over the anterior capsule.
- When the flap is crumpled, the cut /leading edge of rhexis is not visible, increasing the risk of irregular rhexis or extension.
- By keeping the flap well spread and flat over the anterior capsule you would improve your control and it is very easy to achieve the desired size and shape.