Published: 2020-05-26

Comparing the number of attempts required for complete nuclear chop using calibrated and conventional phacotip

Swetank Shekhar, Praveen Malik, Amrendra Kumar, Ravindra Singh


Background: Phacoemulsification is a state of art technique with a steep learning curve the configuration of the phacotip affects the efficacy and execution of the nuclear chopping techniques. Inadequate penetration of phacotip may result in partial thickness nuclear cleavage with residual posterior plane and over enthusiastic penetration may result in posterior capsule rupture. This may be avoided if some estimate can be made preoperatively of the depth of penetration required to achieve full thickness crack.

Methods: A total of 60 eyes of 60 patients with age related cataract with grade 4.0 to 6.9 (LOCS III) fulfilling the inclusion and exclusion criteria were included in the study after written informed consent. They were divided into two groups A and B with 30 patients each randomly using envelope method and were operated using conventional and calibrated phacotips respectively and the number of attempts required to achieve complete nuclear chop was noted.

Results: In group A, vertical chop was safely and effectively done is 23 patients in just one attempt while it took 2 attempts in 6 patients and 3 attempts in 1 patient. In group B, it took just one attempt in 26 patients while 2 attempts were required in 4 patients. The two groups were comparable (p value 0.453) and was found to be statistically significant.

Conclusions: With the use of a calibrated phacotip, the surgeon already knows to what depth he has to penetrate the tip into the center of nucleus depending upon the grade of cataract which results in safe and effective chop in minimum attempts where as in the conventional phacotip, it is more of a blind process. Hence the calibrated phacotip has taken the guess work out of question.


Calibrated phacotip, Lens opacity classification system III, Nuclear chop, Posterior capsule rupture

Full Text:



Prasad S. Phacoemulsification learning curve: experience of two junior trainee ophthalmologists. J Catar Refrac Surg. 1998 Jan 1;24(1):73-7.

Corey RP, Olson RJ. Surgical outcomes of cataract extractions performed by residents using phacoemulsification. J Catar Refrac Surg. 1998 Jan 1;24(1):66-72.

Moore RL, Victoria DE, Silva R. Vertical phaco chop with infinity. J Catar Refrac Surg. 2010;36(2):191-370.

Arnold PA, Brothers L, Arbisser. Phacoemulsification of mature nucleus. J Catar Refrac Surg. 2005;6:1061-2.

Malik P, Dewan T. Calibrated chop technique for effective vertical chop in various grades of cataract using calibrated phacotip. ASCRS. 2011;04:117-20.

Mahatme V. Wood cutter technique splits hard nuclei effectively. Rome 2001, Rome Sympos Catar, Glau Refrac Surg. 2001;02:1230-4.

Fine IH. The chip and flip phacoemulsification technique. J Catar Refrac Surg. 1991 May 1;17(3):366-71.

Gimbel HV. Divide and conquer nucleofractis phacoemulsification: development and variations. J Catar Refrac Surg. 1991 May 1;17(3):281-91.

Koch PS, Katzen LE. Stop and chop phacoemulsification. J Catar Refrac Surg. 1994 Sep 1;20(5):566-70.

Maloney WF, Dillman D: Fractional 2:4 phaco. In Koch P, Davidson J, editors: Phacoemulsification techniques, Thorafare NJ; 1991:241-255.

Thomas R, Naveen S, Jacob A, Braganza A. Visual outcome and complications of residents learning phacoemulsification. Ind J Ophthalmol. 1997 Dec 1;45(4):215.

Albanis CV, Dwyer MA, Ernest JT. Outcomes of extracapsular cataract extraction and phacoemulsification performed in a university training program. Ophthalmic Surgery, Lasers and Imaging Retina. 1998 Aug 1;29(8):643-8.