Fortunately with modern Phacoemulsification technology combined with proper surgical technique, corneal decompensation following cataract surgery has become very rare indeed. However there are several patient factors where corneal decompensation is more likely.
Furthermore with patients electing to have cataract surgery and refractive lens exchange at an increasingly younger age together with greater longevity it is essential for us to ensure that we protect the precious endothelial cell layer at all times to avoid the potential for an epidemic of pseudophakic bullous keratopathy (PBK) in years to come.
Patient expectation from cataract surgery also continues to increase and many of our patients expect to have perfect vision from as early as the first post-operative day. The main determinant of first day vision post cataract surgery is the extent to which the endothelium has been protected during surgery.
Allon Barsam uses the soft shell technique in any case in which he is particularly concerned with endothelial protection. Before carrying out his capsulorhexis he places a small amount of dispersive viscoelastic (OVD) into the AC (he uses viscoat). He then places a larger amount of cohesive OVD (healon or provisc) underneath it and watches the dispersive OVD spread upwards over the endothelium. If necessary this maneuver can be repeated before starting phaco and/or before inserting the IOL. Care must be taken not to overfill with dispersive OVD before phaco as dispersive OVD conducts heat and the chances of a wound burn are higher. If necessary aspirate some OVD before commencing phaco. At the end the case he is even more careful to ensure that all OVD is aspirated due to the risk of a day one IOP spike.
The reason that he does not use the soft-shell technique in all cases is that dispersive viscoelastic commonly causes a day one IOP spike which he pre-emptively treats with oral acetozolamide but he does not feel that this is necessary in all patients. As well as the soft-shell technique, below are described a few other surgical pearls specific to different scenarios:
Other patient factors where endothelial protection is especially important and in which he would use a soft shell technique include:
Eric Donnenfeld et al wrote a nice paper  looking at the effect of pre-operative topical steroid pulsing on endothelial protection. The theory being that the endothelial cell layer is neuroectoderm derived and as with all ‘neurological’ tissue responds more favourably to surgically induced injury when the inflammatory system is pre-emptively downregulated. The results of the paper are convincing and we have seen the effect of this regime in every day practice. The paper looks at the effect of durezol drops which are not readily available in the UK. We therefore use g. dexamethasone 0.1% and give all of our patients 4 doses of this in the one hour prior to surgery.
We continually strive to raise the bar in what can be achieved with modern cataract surgery. In order to ensure that patients achieve not only rapid visual recovery but also enjoy long term excellent vision from our surgery it is essential that we properly respect and protect the endothelial cell layer during surgery.
1. Donnenfeld ED, Holland EJ, Solomon KD, Fiore J, Gobbo A, Prince J, Sandoval HP, Shull ER, Perry HD. A multicenter randomized controlled fellow eye trial of pulse-dosed difluprednate 0.05% versus prednisolone acetate 1% in cataract surgery. Am J Ophthalmol. 2011 Oct;152(4):609-617