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Video Report

Zero Phaco Microincision Cataract Surgery: The HACC Technique

Vaitheeswaran K, Garg S, Grover R, Nadar M, Sharma S

Department of Opthalmology, St Stephens Hospital, Tees Hazari, Delhi-110054, India

Correspondence: Dr Krishna Vaitheeswaran
Email: krishna_v47@rediff.com or krish704@hotmail.com
Tel: 91-11-22725525
Fax: 91-11-23932412

Date of acceptance: 15th April 2005

Capsulorhexis is done using a bent 26G needle. The nucleus is cracked using a blunt bimanual irrigating-aspirating cannula. The nuclear fragments are chopped and aspirated from periphery to centre using an irrigating chopper and an aspirating cannula fashioned from a 20G needle.


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Introduction

Microincision cataract surgery provides advantages of wound stability, improved control and reduced chamber turbulence, resulting in early visual rehabilitation and improved results.[1,2] Current techniques rely predominantly on ultrasound based phaco-emulsification, which relies heavily on expensive equipment and consumables, restricting universal application of this technique particularly in resource-limited settings such as developing countries. Furthermore, there is concern that the use of a bare phaco probe through a sub-millimeter clear corneal incision may result in enhanced complications in the form of corneal burns.[3,4]

The HACC (High aspiration controlled chop) technique is a technique for microincision cataract surgery which is independent of energy-based phacoemulsification. This is a pre-chop, zero-phaco technique which allows easy removal of cataracts of nuclear hardness up to grade 4.


Technique

A. Incision
Two incisions were made in the clear cornea using a MVR blade. These are fashioned so as to taper inward, reducing micro-leaks to a minimum. A disposable aspiration cannula was fashioned from a 20 gauge needle and used instead of the standard phaco hand piece and needle.

B. Nucleus Preparation
The nucleus was cracked so as to enable further management. This was done using a modified vertical chop technique using two choppers.

C. Nuclear Aspiration
The fragments were lifted out, chopped and aspirated. The chopping was done using an irrigating chopper fashioned at the time of surgery from a 20 gauge needle. Each nuclear fragment was delaminated and chopped in a controlled manner, aspirating the softer peripheral portions first and leaving the harder centre for the end.

 

Discussion

Microincision cataract surgery with the zero-phaco HACC technique is a safe and efficient technique with inherent advantages of elimination of corneal burn and better immediate postoperative visual acuity. Patient comfort and functional improvement are superior in this technique than that seen after conventional bimanual phacoemulsification. The zero-phaco HACC technique is a sub-millimeter surgical technique which may be performed using just an automated irrigation-aspiration device. It may be used even in areas in the developing world where there is limited access to modern phaco machines and expensive consumables, thus extending the benefits of modern cataract technology in a low-cost, financially viable way. The use of readily available disposables as tools for the procedure reduces cost and provides freedom to use the smallest possible incision size at all times. With optimal choice of the irrigation and aspirating diameters, fluidic control was found to be easier. Newer aspiration systems may provide greater control enabling this technique to play a greater role in the surgical intervention for cataract.

With this technique, nuclear manipulation is chiefly in the bag or in the pupillary plane. With no ultrasound needed within the anterior chamber, there is less turbulence and consequently less risk of damage to either the corneal endothelium or the posterior capsule. The irrigating chopper and aspirating cannula may be fashioned intraoperatively depending on the nuclear hardness, so as to enable maximum safety as also the smallest incision size. Harder nuclei may be removed using larger bore aspirating cannula while smaller diameters may be used for softer nuclei. This optimizes incision size as well as operating time. However, aspiration diameter larger than 0.9 (20G) was seldom required. The irrigating chopper fashioned from the 20G needle can easily introduced through the existing side port with no need for extension as is sometimes required with other irrigating choppers.

We are not aware of a previous description of a zero-phaco technique for sub-millimeter cataract surgery. With advantages of low costs and near universal application, the technique may play a major role in providing quality surgical intervention to a large population with low vision due to cataract, particularly in the economically disadvantaged areas of the world.

 

References

1. Agarwal A, Agarwal A, Agarwal S, Narang P, narang S. Phaconit: phacoemulsification through a 0.9mm corneal incision. J Cataract Refract Surg. 2001; 27(10): 1548-52.

2. Braga-Mele R, Liu E. Feasibility of sleeveless bimanual phacoemulsification with the Millennium microsurgical system. J Cataract Refract Surg. 2003;29(11):2199-203.

3. Donnenfeld ED, Olson RJ, Solomon R, Finger PT, Biser SA, Perry HD, Doshi S. Efficacy and wound-temperature gradient of whitestar. J Cataract Refract Surg. 2003 Jun;29(6):1097-100

4. Mackool RJ. Temperature during bimanual phacoemulsification. J Cataract Refract Surg. 2004 Apr;30(4):732.