A clinical review of the IOLAB Azar model 91Z flexible anterior chamber intraocular lens.

The IOLAB AZAR 91Z flexible anterior chamber intraocular lens may have the highest complication rate of any contemporary intraocular implant. Over 40,000 of these implants were inserted in human eyes. The complications of this lens includes a much higher than normal rate of chronic inflammation, cystoid macular edema, glaucoma, hyphema, vitreous hemorrhage, and pseudophakic bullous keratopathy. These complications together constitute the multiple manifestations of the UGH Plus syndrome. These complications tend to increase with time. The failure of the 91Z can be ascribed to problems of design and manufacturing causing excess movement, vaulting, and irritation of ocular tissue. Patients with this implant need to be notified of the high complication rate and the need for frequent follow-up. Most 91Z complications are recurrent or persistent and respond best to removal of the implant. Removal of the 91Z requires special technique to avoid traumatizing the eye. The design, materials, testing, manufacture, and recall of the 91Z needs close study to prevent another such problem prone lens from reaching widespread use.