The following 2 topics - Hydroprocedures and Nucleus Phacoemulsification were presented by Dr. Shabbir Hussain on 28-07-2002 at IMA Hall. The meeting was sponsored by Novartis Pharma.


Hydroprocedures

Hydroprocedures comprises of :-

        1. Hydrodissection
        2. Hydrodelineation

          In both irrigating , fluid is injected through a cannula into various anatomical layers of cataractous lens

      Hydrodissection

      Infusion fluid is injected exactly between the anterior capsule and the cortex , so that the fluid wave dissects all around the capsular bag and separates it from the entire lens nucleus ,epinucleus and cortex.

      This helps nucleus rotation and manipulation during nucleus emulsification

      Technique :-

      1. Hydrodissection cannula which is blunt tipped , is mounted on a syringe and

      is guided along the subcapsular plane.

      2. The capsule is lifted and small amount of fluid injected along the subcapsular

      area at 6 o’clock position and in different quadrants.

      1. Indications that the hydrodissection has occurred is shallowing of anterior chamber signifying entrapped fluid in subcapsular layer of the lens at one pole. A gentle tap in the shallow part results in completion of the hydrodissection with associated chamber deepening.

      2. Free rotation of the nucleus suggests that successful hydrodissection has been performed .

    Importance :-

    Hydrodissection is performed for the followability.

    It separates the nucleus from capsular bag so that it will be free to rotate within the bag .

    Allowing each sequential piece of the nucleus to be rotated into the best position for removal.

     


    Hydrodelineation

     

     

    Infusion fluid is injected between epinucleus and nucleus . This fluid wave appears as a golden ring under the microscope.

     

    The Posterior epinucleus created by hydrodelineation acts as a cushion safe guarding to a certain extent the posterior capsule during nucleus emulsification apart from debulking the nucleus.

    Technique:

       

      1. A small guage 26-30 G cannula is attached to the syringe with BSS.
      2. It is passed into the nucleus at the edge of the capsulorhexis until it meets resistance ,the point of resistance is where the soft outer nucleus ends and the firm inner nucleus begins .
      3. At the point of resistance ,the cannula is pulled back a fraction of a mm and fluid is injected .The fluid passes into the body of the cataract and creates a cleavage plane, usually identified by the appearance of a golden ring around the inner nucleus.

Importance :-

Hydrodelineation is performed for safety .

Once the firm inner nucleus is separated from the softer outer nucleus , we gain significant margin of safety ,the firm nucleus could be emulsified within a thick cushion of soft outer nucleus.


Nucleus Emulsification

The management of the nucleus is the fundamental step in phacoemulsification surgery and number of innovative techniques have been developed.

The basic steps of the processes, involved in Phacoemulsification are :-
        1. Sculpting
        2. Nuclear segmentation
        3. Nuclear rotation
        4. Nuclear fragment removal

     

Endocapsular Phacoemulsification can be divided into the following four categories :-
        1. Phacoemulsification without nucleus cleavage
        2. Phacoemulsification with nucleus cleavage
        3. Phacoemulsification with nucleus cracking
        4. Intercapsular Phacoemulsification

     

Here I will be restricting myself to emulsification technique with nucleus cracking

The main principle of this technique is to mechanically reduce the size of the nucleus in shortest possible time, with the least use of phaco energy and minimal surgical trauma to adjacent structure.

 

Various cracking techniques are :_

           

          1. Four quadrant cracking

             


             

          2. Fractional 2 : 4 phaco

             

             

             

             

          3. Crater divide & conquer

             

             

          4. Phaco chop

             

             

          5. Phaco Stop and chop