Clinicopathologic Reports, Case Reports, and Small Case Series
March 2002

Calcium Precipitation on the Optical Surfaces of a Foldable Intraocular Lens: A Clinicopathological Correlation

Author Affiliations



Copyright 2002 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.2002

Arch Ophthalmol. 2002;120(3):391-393. doi:

An intraocular lens (IOL) (Hydroview; Bausch & Lomb, Rochester, NY) developed late postoperative opacification of its optical surface, causing significant visual symptoms that required explantation. The lens was processed in our laboratory, and the lens optic, composed of a hydrophilic acrylic polymer, was stained with alizarin red and the von Kossa stain for calcium. The lens also underwent scanning electron microscopy and energy dispersive x-ray spectroscopy of its anterior optical surface. These analyses revealed that the opacity was caused by deposition of calcium phosphate on the lens surface. This process appeared to be dystrophic calcification of unknown cause.

Recent reports of IOL calcification have raised concerns regarding the long-term biocompatibility of 2 modern hydrophilic acrylic foldable lenses: the Bausch & Lomb Hydroview IOL and the Medical Developmental Research (Clearwater, Fla) SC60B-OUV.13 In this study, we describe the typical appearance of late postoperative opacification of the former lens with pathological confirmation of IOL calcification.

Report of a Case

An 80-year-old man underwent uneventful phacoemulsification of the left eye and capsular bag fixation of a Hydroview IOL model H60M by one of us (J.P.G.). The patient had a history of rheumatoid arthritis and type 2 diabetes mellitus. The IOL was implanted in the capsular bag under viscoelastics (Viscoat; Alcon Surgical, Fort Worth, Tex). The intraoperative irrigating solution used was balanced salt solution with adrenaline (1:1000). Subconjunctival injections of gentamicin sulfate and betamethasone sodium phosphate were performed at the end of the procedure. Postoperatively, tobramycin and prednisone ophthalmic drops were tapered over 4 weeks. The best-corrected visual acuity 1 month postoperatively was 20/30 OS.

The patient noted a marked loss of vision associated with intense glare 16 months postoperatively. The best-corrected visual acuity was reduced to light perception. Slitlamp examination of the anterior segment revealed a dusty haze or granularity present on the optical surfaces of the lens (Figure 1). Evaluation of the posterior segment was not possible because of hazy media secondary to IOL opacification. As attempts to clear the optical surfaces of the IOL with the Nd:YAG laser were not successful, the IOL was explanted 20 months postoperatively. It was freed from the surrounding capsule by viscodissection and then removed through a 6.0-mm sclerocorneal tunnel. A rigid polymethyl-methacrylate IOL model P 359 (Bausch & Lomb) was placed in the capsular bag. Incisional biopsies of conjunctiva and iris were performed during IOL removal and exchange to rule out the presence of dystrophic calcification in those tissues. The patient's visual acuity improved to 20/400 with absence of glare immediately after the IOL exchange. Evaluation of the posterior segment at this stage revealed presence of severe nonproliferative diabetic retinopathy. However, the best-corrected visual acuity decreased to light perception after 2 months' follow-up because of the worsening of the diabetic retinopathy/maculopathy, which was further investigated and treated in consultation with a retina specialist.

Figure 1
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Slitlamp photograph of an implanted Hydroview intraocular lens (Bausch & Lomb, Rochester, NY) with a granularity present on the optic.

Gross and microscopic analyses of the explanted IOL were performed, and photographs were taken to document the findings. The IOL was then bisected for histochemical and scanning electron microscopic evaluation. For histochemical analysis, one half of the IOL was rinsed in distilled water, immersed in a 1% alizarin red solution for 2 minutes, rinsed again in distilled water, and reexamined under the light microscope. A slice of the optic of the Hydroview IOL was performed, the resultant cylindrical block was dehydrated and embedded in paraffin, and sagittal sections were performed. Special stains included the von Kossa stain for calcium.4,5 The other half of the lens optic was air-dried at room temperature for 7 days, sputter-coated with aluminum, and examined under a 2500 Delta scanning electron microscope (Nissei Sangyo America, Schaumburg, Ill) equipped with a Kevex (Scotts Valley, Calif) x-ray detector. The conjunctival and iris tissue were also prepared for histological/histochemical examination and stained with the alizarin red/light green and von Kossa methods.

Pathologic Findings

Gross evaluation revealed that the optical surfaces of the unstained IOL were covered by a layer of irregular granular deposits. The deposits occurred on both anterior and posterior optical surfaces, but not on the haptics (Figure 2). They stained positive with alizarin red (Figure 3). Sagittal sections of the optic of the IOL stained using the von Kossa method were positive, showing a continuous layer of dark brown, irregular granules on all surfaces (anterior, posterior, and edges) of the lens (Figure 4). Scanning electron microscopic analysis of the optic's anterior surface revealed granular deposits composed of multiple spherical-ovoid structures (Figure 5). Energy dispersive x-ray spectroscopy performed on the surface shown in Figure 5 revealed a high peak for calcium and a lesser peak for phosphate (Figure 6). Histochemical evaluation of the conjunctival and iris biopsy specimens, using alizarin red stain and von Kossa silver stain, did not reveal any evidence of calcium salts (Figure 7).

Figure 2
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Photomicrograph of the explanted opacified Hydroview intraocular lens (Bausch & Lomb, Rochester, NY) showing the confluent deposits on the anterior optical surface. The polymethyl-methacrylate haptics are free of any deposits (original magnification times100).

Figure 3
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Photomicrograph of the bisected Hydroview intraocular lens (Bausch & Lomb, Rochester, NY) with the optical surface stained positive (alizarin red, original magnification times20).

Figure 4
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Photomicrograph of a sagittal section through the optic of the Hydroview intraocular lens (Bausch & Lomb, Rochester, NY). The lens material was dissolved during the preparation for histological examination, but the optical edge is delineated by a continuous layer of dark brown, irregular granules (von Kossa stain, original magnification ×200).

Figure 5
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Scanning electron photomicrograph from the anterior optical surface of the Hydroview intraocular lens (Bausch & Lomb, Rochester, NY). The deposits are composed of multiple globules of variable sizes (original magnification ×800).

Figure 6
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Energy dispersive x-ray spectrum from the Hydroview intraocular lens (Bausch & Lomb, Rochester, NY) (coated with aluminum) with peaks of calcium (Ca) and phosphate (P) (arrows) at the level of the granular deposits. S indicates sulfur; O, oxygen; Na, sodium; and Al, aluminum.

Figure 7
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Photomicrographs from the histological sections of the conjunctiva (A) and iris (B). No dystrophic calcification was observed in the sections (alizarin red/light green, original magnification ×200).


We have recently reported on the lens described here, the Bausch & Lomb Hydroview,1,2 as well as another hydrophilic IOL, the Medical Developmental Research SC60B-OUV.3 With both lens designs, the opacification appears to be related in part to calcium deposition on the external optical surfaces (in the case of the Hydroview) or within the IOL optic (in the case of the SC60B-OUV). Our first publication on calcification of the Hydroview design reported on 1 explant from Australia and 4 explants from Sweden.2 This is the first report of calcification of Hydroview lenses observed in Canada. As in the previous cases, the dystrophic calcification was limited to the external optical surfaces of the lens. In the case reported here, the absence of dystrophic calcification in ocular anatomical structures of the patient, such as conjunctiva and iris, was confirmed histopathologically. More than 400 000 Hydroview lenses have been implanted in 4000 centers worldwide. We are aware of 272 similar cases of late postoperative opacification, from which 83 lenses were explanted because of significant visual impairment. These reports have been clustered in 29 centers, including Hong Kong, Canada, Sweden, Germany, and Australia, among others. One of us (J.P.G.) has explanted several Hydroview IOLs for similar reasons. Although the composition of the deposits has been determined to be hydroxyapatite, the pathogenesis of this complication is still obscure. Awareness of this condition is warranted as Nd:YAG laser treatment does not seem to be helpful in removing the deposits from the lens surfaces and possibly damages the surrounding capsule, compromising in-the-bag fixation of a new IOL after explantation of the opacified lens.

This study was supported in part by an unrestricted grant from Research to Prevent Blindness Inc, New York, NY.

This study was presented in part at the annual meeting of the American Academy of Ophthalmology, Dallas, Tex, October 24, 2000.

We thank Joyce Edmonds, HTL (Storm Eye Institute), who provided assistance with histochemical analysis, and Dana G. Dunkelberger, PhD (Electron Microscopy Center, University of South Carolina, Columbia), who kindly provided assistance with surface analysis.

Corresponding author and reprints: Liliana Werner, MD, PhD, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, 167 Ashley Ave, PO Box 250676, Charleston, SC 29425-5536 (e-mail:

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