A capsulorrhexis (sometimes spelt capsulorhexis)
is a common name for a a surgical procedure in which a continuous circular
tear (rather than just an incision)
is made the capsule that encloses the lens
of the eye.
This capsule encloses the lens, separating it from the aqueous
humour in front of , or "anterior to" the lens, and the
humour behind, or "posterior to" the lens. Note
that the word-stem "capsulo-" refers
to the capsule, a useful start in recognising and understanding
this and related terms.
The capsulorrhexis procedure is also known by the more
technically exact term:
Continuous Curvilinear Capsulorhexis, or CCC
The context of this procedure is generally to remove the lens from its
capsule, during cataract
surgery. That is, removal of cataracts using modern techniques involves
opening the lens capsule (to remove just the lens) - as compared
with the older technique (called "intracapsular cataract extraction")
in which the whole lens and capsule were removed. Modern techniques
enable removal of most cataract material while leaving the capsule itself
otherwise intact. That is useful because the capsule forms a barrier between
the front and back of the eye, hence preventing the vitreous
humour from moving forwards. Modern techniques therefore enable the
artificial intraocular lens (introduced during cataract surgery) to be
ideally located in the eye, i.e. held securely in place yet away from
contact with other structures.
The capsulorrhexis technique is said to have the benefit
(over a capsulotomy)
of leaving the residual capsule more resistant to tearing during surgery.
However, these methods are not directly comparable as they may be performed
for different reasons, as a part of different overall procedures.
This section includes short definitions of clinical and surgical procedures
concerning the eyes and human visual system. For definitions of other
terms in this category, choose from the list to the left. Other related
pages include the diagram
of the eye, and definitions
of parts of the eye, a description
of the human retina, and the section about disorders
of the eye and visual system.