Micro-incision cataract surgery performed with a viscoelastic/ intraocular anaesthesia combination is significantly less painful than surgery performed with topical anaesthesia, particularly during the IOL insertion phase of the procedure, according to the results of a study presented at a conference of the Irish College of Ophthalmologists by David Shahnazaryan FRCS, Dublin Eye and Ear Hospital Dublin, Ireland.
The study involved 68 consecutive patients scheduled for micro incision cataract surgery. They included 39 women and 29 men with a median age of 73.5 years (range: 47 to 87 years). The Dublin investigators randomly allocated the patients to undergo either micro-incision cataract surgery (MICS) with topical anaesthesia or MICS with topical anaesthesia in addition to intracameral anaesthesia with a commercial formulation combining 1 per cent lignocaine with a viscoelastic (Visthesia ®, Zeiss). In all procedures Dr Shahnazaryan and his associates inserted the IOLs using 2.2 mm incisions and wound-assisted technique.
In their postoperative responses to questions using a visual analogue pain score, the mean score during IOL insertion was less than three in both groups, indicating only mild pain or discomfort. However, while all the patients in the Visthesia group reported only mild discomfort, 24 per cent of those in the topical anaesthesia alone group reported moderate pain.
"Visthesia was associated with significantly less pain and discomfort during IOL insertion. However, it is more expensive and perhaps the addition of 1 per cent lignocaine intracamerally could achieve similar effect at less cost," Dr Shanazaryan concluded.