|Year : 2021 | Volume
| Issue : 3 | Page : 405-406
Primary calcification in a hydrophobic acrylic intraocular lens - A material analysis
Harsha Bhattacharjee, Henal Javeri, Suklengmung Buragohain, Dipankar Das
Department of Cataract and Refractive Surgery, Sri Sankaradeva Nethralaya, Assam, Guwahati, India
|Date of Submission||28-Nov-2020|
|Date of Acceptance||13-Feb-2021|
|Date of Web Publication||02-Jul-2021|
Dr. Henal Javeri
Sri Sankaradeva Nethralaya, 96 Basistha Road, Saurabh Nagar, Beltola Tiniali, Guwahati - 781 028, Assam
Source of Support: None, Conflict of Interest: None
Keywords: Primary calcification, acrylic hydrophobic IOL, Scanning electron microscopy
|How to cite this article:|
Bhattacharjee H, Javeri H, Buragohain S, Das D. Primary calcification in a hydrophobic acrylic intraocular lens - A material analysis. Indian J Ophthalmol Case Rep 2021;1:405-6
|How to cite this URL:|
Bhattacharjee H, Javeri H, Buragohain S, Das D. Primary calcification in a hydrophobic acrylic intraocular lens - A material analysis. Indian J Ophthalmol Case Rep [serial online] 2021 [cited 2021 Jul 26];1:405-6. Available from: https://www.ijoreports.in/text.asp?2021/1/3/405/320075
Primary calcification of an intraocular lens (IOL) occurs due to the polymer property or its manufacturing/storage methods, whereas secondary type is because of deposits on the lens' surface after disruption of the blood–aqueous barrier. Although calcification of various IOL biomaterials is documented,, primary calcification of hydrophobic acrylic IOL has not yet been reported in the literature.
A 52-year-old man, who had previously undergone cataract extraction and acrylic hydrophobic IOL implantation 8 years back at our institute, presented with a 1-day history of blunt trauma due to a fall. On examination, subconjunctival hemorrhage and acute traumatic posterior dislocation of IOL were noted. No vitritis, vitreous hemorrhage, or any other significant finding were noted. He had no systemic co-morbidities. He underwent an uneventful pars plana vitrectomy with IOL explanation and secondary scleral suture fixated IOL implantation. Postoperatively, the vision and ocular condition was unremarkable. Various procedures for material analyses of the explanted IOL were performed.
On light microscopy, under low magnification, the IOL appeared hazy with non-homogenous granularities over the optic [Figure 1]. The deposits stained positive for calcium with Alizarin red (1%) stain [Figure 2]a. On diffractive photography, focussing on one of the many calcium deposits, vacuoles of different sizes and shapes were seen in the substance [Figure 2]b.
|Figure 1: Light microscopic photograph of a part of the optic and one haptic of an explanted single piece hydrophobic IOL along with the capsular bag. Note – Hazy optic with non-homogenously spread black and white fine deposits. Pigments are noted over the anterior capsule|
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|Figure 2: (a): Positive Alizarin Red staining for calcium. (black arrow). (b): Diffractive photography (Axiocam MRC, Zeiss) of a single calcium deposit on high magnification. Note multiple vacuolated spaces of different sizes in the substance. (green arrow). (c): SEM analysis photograph (850X magnification). Note the globular white “millet seed-like” calcium deposit collection in one area (blue arrow) over a diffusely eroded surface of IOL optic. (d): On 2.16KX magnification, capturing a single spherical deposit showing smaller round particles (yellow arrow) in the deposit, corresponding to the findings seen on diffractive photography in Figure 2b|
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On routine SEM (Hitachi S 3000 N EXAX Genesis VP SEM) under 850X magnification, the surface of the optic appeared uneven and roughened. Small globular white millet-seed-like deposits of varying sizes were seen spread over the surface, aggregated in clumps in certain areas [Figure 2]c. On examining each one of the many globular deposits under higher magnification (2.16 KX), it appeared to further contain small multiple dispersed round particles [Figure 2]d. Energy dispersive X-ray spectroscopy performed over the entire surface confirmed the surface granularities observed on light microscopy to be calcium [Figure 3].
|Figure 3: Yellow peak on EDS graph confirming Calcium depositions over the IOL surface. (White arrow)|
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| Discussion|| |
Hydrolytic degradation of a polymer due to surface absorption of water and subsequent surface erosion by the dynamic aqueous results in the formation of surface cracks and deep pores over time. Our SEM analysis also revealed IOL surface irregularity and small pores. This process of degradation, as described in polymer chemistry, is followed by mineralization and may explain primary calcification.
In the above case, no associated systemic or ocular conditions were present. Serum calcium level testing was not done since the patient had no medical history suggestive of imbalance in levels. We believe that in absence of any other cause, the present observed specimen in vivo got calcified due to primary reasons related to IOL biomaterial and the SEM-EDS findings corroborate the same.
Mr. Apurba Deka, BMLT, Ocular Pathology Department, Sri Sankaradeva Nethralaya, Guwahati, India.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]