Hydrodelineation is a method of separating an outer shell (or multiple shells) of the

lens A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...

of the eye from the central compact mass of inner nuclear cataract (also called endonucleus) during a cataract surgery by the forceful irrigation of a fluid into the mass of the nucleus. While

hydrodissection Hydrodissection is the use of a directed jet of water to surgically separate tissues. It is generally used to develop tissue planes or divide soft tissues with less trauma than dissection using a cutting instrument. By using an appropriate pressure ...

disconnects the lens from the lens capsule, hydrodelineation splits it into endonuclear and epinuclear sections thus reducing the size of the hard nucleus, making its extraction possible through a smaller incision. This also facilitates

phacoemulsification Phacoemulsification is a cataract surgery method in which the internal lens of the eye which has developed a cataract is emulsified with the tip of an ultrasonic handpiece and aspirated from the eye. Aspirated fluids are replaced with irrigation ...

. An injection of fluid into the body of the lens through the cortex against the nucleus of a cataract separates the hardened nuclear cataract from the softer lens cortex shell by flowing along the interface between them. The smaller hard nucleus can then be expeditiously phacoemulsified, while the posterior cortecx serves as a buffer protecting the posterior capsule membrane. The smaller size of the separated nucleus requires less deep and less peripheral grooving and produces smaller fragments after cracking or chopping. The posterior cortex also maintains the shape of the capsule which reduces risk of posterior capsule rupture.

References

{{Eye procedures Eye surgery