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PURPOSE :
The existing chop technique of nuclear fragmentation is difficult to perform in hard nuclear Cataract. Author has tried new Woodcutter's Technique.

METHOD :
Out of 90 eyes of grade III & IV nucleus, Karate - Chop technique was performed in 45 eyes. Effective Phaco time required for surgery noted. Duration from touching nucleus by Phaco Tip till its division into four fragments was noted (Cleavage Time). This was compared using new Woodcutter's Technique in other 45 eyes.

RESULTS :
Effective Phaco time , Cleavage time and strokes required are less in Woodcutter's Technique & the difference is statistically significant

CONCLUSION :
New Woodcutter's Technique of nuclear fragmentation offers better alternative to existing Chop Technique

PURPOSE :
Dividing grade III & grade IV nuclei in phacoemulsification procedure is a tough job. Amongst the existing options karate chop technique serves the purpose best. Woodcutter's technique is author's discovery which is compared to asses it's efficacy. When a woodcutter wants to divide a wooden log into two pieces, what he does is he first nails a chisel in the log. Some distance away from the chisel, he hammers on the log with an axe; goes on hammering, slowly approaching chisel. As soon as he is very close to the chisel, the wooden log automatically gets divided into two vertical fragments(as shown in fig.1).

In karate chop technique, we normally hold the nucleus with phaco tip & then move chopper towards the phaco tip. As against this, in Woodcutters, chopper is placed at same place & not moved. Instead, the phaco tip, which is holding the nucleus, is moved towards the chopper (with phaco on). This automatically divides the nucleus in two fragments, when phaco tip approaches near the chopper thus, chooper acts like a chisel & phaco tip like an axeas (as shown in fig.2 )

MATERIALS & METHODS :

PATIENT SELECTION : Senile cataract of grade III & grade IV were selected. Cases which were excluded from study included cases where pupil was not dilating beyond 6 mm or cases with very shallow anterior chamber ( grade IV Von Horrick Test ), low corneal endothelial count or having pseudoexfoliation. If
either of the techniques needed to be abandoned & changed to some other technique during procedure, such case was not considered for this study.
Cases were subjected to karate chop and woodcutters technique alternately. Without doing sculpting or grooving, the phaco tip was introduced in the nucleus. The moment the preset vaccum was achieved, time calculation was started. The chopper was brought to the tip & tried to divide the nucleus in karate chop technique and phacotip waas brought to the chopper site in woodcutters technique. This resulted in either of two things i.e.

Division of nucleus was complete & vaccum was released by releasing footswitch to zero or vent is on. The time from preset vaccum reached to the vent on was measured. This was termed as cleavage time. When all these sequelae are happening, it will be said that the nucleus was divided in one stroke
Division of nucleus is incomplete & vaccum is released by releasing footswitch to zero or vent is on.
One stroke means events taking place from phaco on till vent on; irrespective of whether the nuclear division has occurred successfully or not.
Time from preset vaccum reached to vent on is measured for first stroke. The nucleus is then rotated through 1800 & same procedure repeated. Time for second stroke noted in similar manner. The procedure was repeated till nuclear division was complete. This may require three or even four strokes. As mentioned earlier, time required for each stroke ( from preset vaccum to vent on ) is termed as cleavage time. Sum of all cleavage time will give aggregate cleavage time per division. ( Time required to get complete division of nucleus ).

The effective phaco Time per division was time from starting phaco till division of nucleus (noted in effective phaco time counter of phaco machine). It was separately measured every time for e.g. time for division of nucleus into two pieces, then into three pieces & then into four pieces.

In each group, aggregate effective phaco time per division required in all cases for first division of nucleus was obtained by making a sum of all the values. Similarly aggregate effective phaco time per division for second & third division was also calculated by adding the individual effective phaco time obtained in each case.

RESULTS :
90 Eyes with grade III & grade IV nuclei of senile cataract were studied & results noted down in the charts.

Group	No Of Eyes	Grade Of Nucleus		Aggregate Number of Strokes	Aggregate Effective Phaco Time per division(seconds)			Aggregate Cleavage Time (Seconds)
Group A (Chop Technique)	45	III	IV	292	1^st	2^nd	3^rd	1^st	2^nd	3^rd
Group A (Chop Technique)	45	41	4	292	131	96	94	131	96	94
Group B (Woodcutter's Technique )	45	41	4	153	90	59	59	490	490	125

No significant complications were noticed in any of group & by either of procedure. Complications occurring after division of nucleus into four fragments were not related to the study & hence not considered.

DISCUSSION :
Dividing nucleus into four fragments is the most difficult thing to learn & master in phaco. Karate chop technique is considered to be the best in today's scenario ; for grade III & IV nuclei. Chop technique however requires many strokes & longer time. New woodcutter's technique was discovered to overcome this problem.Observations were subjected to statistical analysis , applying "t'' test.

Results are shown in table 2.

Parameter	Group A (Chop Technique)	Group B (Woodcutter's Technique)	t Value	p Value
No. of Strokes.	No. of Strokes.	3.4	6.1128	P<0.001
Effective PhacoTime (Sec.)	2.06	1.31	5.5397	P<0.001
CleavageTime (Sec.)	5.22	2.777	6.0545	P<0.001

In the present study, it was noticed that number of strokes required to divide nuclei of grade III & IV, are very less in woodcutter's new technique & the difference is statistically highly significant having p value < 0.001. Because of this the surgeon need not rotate the nucleus repeatedly, which has an added advantage of having less stretch on zonules. On the contrary there is more stretch on zonules in karate chop technique. When the number of strokes are less, you are quite away from posterior capsule while dividing nucleus. Multiple strokes means you are going deeper & closer to the posterior capsule.

The effective phaco time per division of nucleus is also less & statistically highly significant with p value < 0.001. The advantages are obvious.

Cleavage time per division is also comparatively quite less in woodcutter's technique & again statistically highly significant ( p value 0.001). No significant complications occurred in any of these techniques.

CONCLUSION :
This comparative study shows that New woodcutter's technique requires less Effective phaco Time, cleavage time as well as less number of strokes. Division of nucleus is quicker & easier with woodcutter's new technique than in established chopping technique.