Aims: To study the clinical features, management, and outcomes of displacement of nuclear fragments into the vitreous (DNFV) complicating phacoemulsification in the United Kingdom.
Methods: Cases were collected prospectively between March 2003 and March 2004 inclusive by active surveillance through the British Ophthalmological Surveillance Unit (BOSU). Details were obtained using incidence questionnaires and follow-up questionnaires after six months. The data used in this paper were obtained from the follow-up questionnaires.
Results: 610 cases were confirmed during the reporting period, for which 387 follow-up questionnaires were received. In 67% of cases a best-corrected Visual Acuity (VA) of 6/12 or better was reported at final follow-up. The most common immediate sequelae of DNFV were intraocular inflammation (85%), corneal oedema (55%), and an intraocular pressure of greater than 30 mmHg (34%). 97% of cases had pars-plana vitreolensectomy, and fragmatome ultrasound-lensectomy was used in over half of these procedures. The median time from cataract to pars-plana vitrectomy surgery for the removal of DNFV was three days, and the majority of cases (68%) had vitrectomy within one week of the first procedure. An intraocular lens had been inserted at the time of the complicated cataract surgery (defined as a "primary-IOL")in 40% of cases, and over three-quarters of these primary-IOL's were subsequently removed (with or without a replacement IOL). Only 67%of eyes that had a primary IOL inserted after DNFV were pseudophakic at final follow up,in contrast to 79%of those eyes that were left aphakic after DNFV (p= 0.008). A best-corrected VA of 6/60 or worse was reported in 14% of cases at final follow up, and was most commonly associated with persistent uveitis, corneal oedema, cystoid macular oedema, optic atrophy, or retinal detachment.
Conclusions: DNFV complicating cataract surgery was followed by a secondary procedure in 97% of cases. 77% of primary-IOLs inserted at the time of DNFV were subsequently removed or replaced and eyes that had received a primary IOL had significantly less chance of being pseudophakic at final follow up,compared with eyes that had been left primarily aphakic at the time of the complicated cataract surgery. The delay before secondary intervention was shorter, fragmatome ultrasound-lensectomy usage was higher, and the retinal detachment rate was lower, when compared with previous studies. Affected eyes still had a worse outcome in terms of visual acuity compared with eyes after uncomplicated cataract surgery.