Vivarte IOL: good refractive results but withdrawn over safety concerns
Correction of very high myopia, i.e. above –9.00 D, remains a controversial topic and new designs of phakic IOLs have spurred great interest in the past five years. Presently, long-term results are becoming available and some interesting conclusions can be drawn, explained Matteo Piovella, MD, who reported his four-year results with one of these lenses at the XXIV Congress of the European Society of Cataract and Refractive Surgeons in London.
Correction of very high myopia, i.e. above –9.00 D, remains a controversial topic and new designs of phakic IOLs have spurred great interest in the past five years. Presently, long-term results are becoming available and some interesting conclusions can be drawn, explained Matteo Piovella, MD, who reported his four-year results with one of these lenses at the XXIV Congress of the European Society of Cataract and Refractive Surgeons in London.
The Vivarte anterior chamber phakic IOL (IOLTECH) appeared to offer promising results, however, safety concerns pertaining to endothelial cell loss have surfaced, require patients are followed-up every six months after implantation. In some cases, patients have required explantation of the anterior chamber lens. In light of these concerns, IOLTECH voluntarily suspended production and marketing of the Vivarte lens last December.
In a letter from the manufacturer to physicians, IOLTECH noted that it agreed with the local French authority, AFSSAPS, to halt the production and sale of the Vivarte anterior chamber lens for the correction of high myopia as well as the Vivarte presbyopic anterior chamber lens and recall all remaining products. Physicians have been advised to continue to monitor patients who have the lens implanted every six months for endothelial cell count loss. The letter explained that the lens should be explanted if the endothelial cell count (ECC) dropped below 1,500 cells/mm2 or there was a greater than 30% ECC drop compared with preoperatively. Physicians were also asked to report all explantations of the lenses to the local authorities.
Meet the implant recipients
All patients who received the lens had to have a minimum anterior chamber depth of 3.2 mm, an ECC greater than 2,500/mm2 , be in good general health, be less than 50 years of age and have an open anterior chamber angle. There could be no evidence of cataract, no angle hyperpigmentation, no vessels in the angle and eccentrical pupil. "The anterior chamber width is extremely important in patient selection," Dr Piovella explained. He implanted the lens prior to its market withdrawal and studied the long-term safety and efficacy in patients. The IOL Master (Carl Zeiss Meditec) was used for white-to-white measurement preoperatively to identify those eyes that were out of range for the IOL size. "The white-to-white measurement can range from 11.0 to 12.5 mm, with 1 mm added for the surgical limbus," he said. "Or the white-to-white measurement could be 10.5 to 12.0 mm with 0.5 mm added for the clear cornea."
Now with new optical coherence tomography (OCT) technology (Visante OCT; Carl Zeiss Meditec), the anterior chamber shape can be evaluated including the anterior chamber depth for endothelium safety, internal dimensions to respect the iris and pupil, symmetry to choose the right axis, and crystalline lens rise and the IOL vault to respect the lens, explained Dr Piovella.
The Vivarte 120 was implanted in eyes with an anterior chamber width of 11.5 to 12.0 mm, the Vivarte 125 needed eyes ranging from 12.1 to 12.5 mm, and the Vivarte 130 required anterior chamber widths of 12.5 to 13.0 mm.
Dr Piovella recommended a final check of the intraoperative measurement using a surgical sizer.
