Dott. Riccardo Giannetti,pubblicazioni: Nucleuscapture

Italian Surgeon Strongly Recommends PCCC for all Cataract Operations to Reduce the Need fo Nd:YAG Capsulotomy

From EURO TIMES A European Outlook on the Worl of Ophthalmology Vol.5 N.3-April 2000

By John F. Henahan

LIVORNO – Posterior continuous curvilinear capsulorhexis (PCCC) with manual nucleus capture

(MNC) should be performed routinely in all patients undergoing cataract surgery to reduce the risks of posterior capsular opacification and the need for its treatment with Nd:YAG laser capsulotomy, suggests Riccardo Giannetti, MD, Eye Departement, Hospital of Livorno, Italy.

Although many surgeons advocate routine use the procedure in the eyes of infants who are at very high risk for posterior capsular opacification or in eyes with already scarred posterior capsuled, the Italian surgeon told Euro Times that it can be safely and effectively performed in the eyes of all patients requiring cataract surgery, regardless of age.

His recommendation is based on the outcome of 2000 cataract operations he carried out using PCCC in patients aged 23 to 94 years between January 1994 and June 1999. At the latest follow-up he has seen only four cases of retinal detachment (RD), which some surgeons have suggested is a risk factor following PCCC.

In all cases the eyes with RD had high myopia with axial lengths greater than 26.5 mm. In addition, the incidence of other potential complications such as vitreous prolapse into the anterior chamber, cystoid macular oedema, and elevated IOP levels was very low, Dr. Giannetti continued.

Phaco-less Nucleus Removal

In all cases included in the study he used his no-suture phaco-less MNC procedure which involves

Reducing the size of the nucleus and capturing the inner nucleus with specially designed instruments developed in conjunction with Janasch/Baush and Lomb-Storz/Katena. The procedure is carried out through a sutureless tunnel, the position of which is determined using a special nomogram developed by the Italian surgeon. The nomogram is based on the pre-operative astigmatism and whether it is with – or against-the rule.

After cleaning up the bag, Dr. Giannetti introduces viscoelastic with a 34 G bent tip cannula and spreads more in the periphery of the bag, while avoiding excess filling. Then using a straight 30 G insulin needle in pushing mode he gently perforates the posterior capsule as centrally as possible in front of Berger’s retro-lental space. The needle movement is well controlled without trauma, so as to avoid penetrating the anterior hyaloid he explained.

Before performing the PCCC (mean 3.55mm) with a Corydon forceps, he fills Berger’s space with a viscoelastic carefully grasping only the posterior capsule, while avoiding the anterior hyaloid. More viscoelastic is then added to fill out the space between the anterior and posterior capsule, prior to in-the-bag implantation of the IOL.

PCCC strongly Recommended

“I usually implant a one piece PMMA IOL with an optic diameter of 5.5mm. I prefer to use the Allergan AMO OS 53 NB lens because it is extremely flexible and has very good centration features. In about 100 cases of small inner nucleus or soft cataract, a 3.5mm micro-tunnel with the manual nucleus capture technique, I’ve implanted foldable IOLs (Allergan SI-SA 40) with the same goos out-comes,” Dr. Giannetti told Euro Times.

Excellent Visual acuity

The procedure maintains “absolute transparency” of the visual axis over the long term, with an increasing and steady improvement in visual acuity over time. When he evaluated the visual outcome of 50 eyes which had undergone the MNC/PCCC procedure, he found that 95% of the patients had a visual acuity of 20/40 or better two weeks after surgery. On the other hand, in another 50 eyes which underwent phacoemulsification without PCCA, only 82% of the eyes saw at that level. In a similar comparison, he found that endothelial cell density after one month and the incidence of cystoid macular edema and the level of intraocular pressure were comparable in both groups.

Dr. Giannetti acknowledged that there were some disadvantages to his procedure, including a 0.9% increased risk of vitreous problems, and the fact that the surgical manoeuvres involved were some-what difficult with a “steep learning curve”. Is is also mandatory that the surgeon have perfect binocular vision with stereopsis and that the procedure be performed under maximum magnification.

“Thanks to the use of the 0.2mm PCCC cannula, heavy viscoelastic and increased use of I.V. mannitol, I suggest that it is possible to etend the use of the PCCC procedure to all cases, including combined cataract-glaucoma operations, secondary IOL implantation with residual posterior capsule of after silicone oil/BSS exchange, using only PCCC. In the past, I have used peribulbar and in only three cases was general anaesthesia since it allows the same performance with fewer complications-“ Dr. Giannetti concluded.

(from Euro Times A European Outlook on the Worl of Ophthalmology Vol.5 N.3-April 2000)