Pathologic Assessment of Complications with Asymmetric or Sulcus Fixation of Square-Edged Hydrophobic Acrylic Intraocular Lenses

Abstract

Objective One-piece hydrophobic acrylic intraocular lenses (IOLs) are not indicated for sulcus fixation because of complications, such as uveitis-glaucoma-hyphema syndrome. Similar complications may also be observed with 3-piece lenses having a square optic edge on the anterior surface. The objective of this study was to provide pathological evidence of complications related to out-of-the-bag fixation of 1-piece or 3-piece hydrophobic acrylic IOLs with anterior and posterior square optic edges. Design Comparative case series with pathology. Participants 559 pseudophakic cadaver eyes obtained from eye banks within the United States, implanted with different IOLs. Methods Anterior segment scanning of whole eyes with a high-frequency ultrasound system, or with a high-resolution anterior segment magnetic resonance imaging, followed by gross examination. Selected eyes were processed for complete histopathological analysis; some of them were explanted before histopathology to allow for direct light microscopic evaluation of the lenses. Main Outcome Measures Findings from imaging, gross, and histopathological evaluation that could be related to out-of-the-bag fixation of the lenses. Results 256 eyes were implanted with hydrophobic acrylic IOLs with anterior and posterior square optic edges; 18 of them exhibiting asymmetric or sulcus IOL fixation (six 1-piece, and twelve 3-piece IOLs) underwent complete histopathological evaluation and were compared to the contralateral eyes with symmetric in-the-bag IOL implantation. Pathological findings were composed of IOL decentration and tilt, pigmentary dispersion within the anterior segment and on the IOL surface, iris transillumination defects, iris changes including vacuolization/disruption/loss of the pigmented layer, iris thinning, and iris atrophy, as well as synechiae and loop erosion in the case of 3-piece lenses. Findings were more significant in comparison with the control contralateral eyes, and were particularly evident in relation to the sulcus-fixated haptic in the case of 1-piece lenses. The majority of the eyes with 3-piece lenses showed signs of complicated surgery. Conclusions This study provides pathological correlation of complications that were clinically reported in the peer-reviewed literature in relation to sulcus fixation of one-piece hydrophobic acrylic IOLs. The eyes with 3-piece lenses generally exhibited evidences of complicated surgery; therefore all pathological findings in those cases may not be strictly attributed to the out-of-the-bag fixation.

Pathologic Comparison of Asymmetric or Sulcus Fixation of 3-Piece Intraocular Lenses with Square Versus Round Anterior Optic Edges

“…18 The methodology used was the same as in the current study; basically, pseudophakic cadaver eyes obtained from eye banks within the United States, implanted with different IOLs were evaluated. Anterior segment scanning of whole eyes with the same high-frequency ultrasound system or the high-resolution anterior segment magnetic resonance imaging was done, followed by gross examination.…”

“…We were looking for any findings from imaging, gross, and histopathologic evaluation that could be related to out-of-the-bag fixation of the lenses. 18 …”

“…Findings were more significant in comparison with the control contralateral eyes and were particularly evident in relation to the sulcus-fixated haptic in the case of 1-piece lenses. 18 …”

“…This is a follow up of a previously published study, which provided pathologic evidence of complications related to out-of-the-bag fixation of 1-piece or 3-piece hydrophobic acrylic IOLs with anterior and posterior square optic edges. 18 …”

Transillumination defects following in-the-bag single-piece intraocular lens implantation and trabeculectomy with mini-shunt

“…5 A third case involved rubbing of the posterior surface of the iris by the inferior haptic of the IOL, which was in the bag but deformed. 6 Kirk et al 9 describe dramatic pathologic correlations of clinically reported complications of sulcus fixation or asymmetric bag-sulcus fixation of the haptics of single-piece hydrophobic acrylic IOLs. Pathologic findings demonstrated IOL decentration and tilt, pigmentary dispersion, iris transillumination defects and iris erosion, vacuolization, atrophy, thinning, and synechiae and were attributed to the square anterior and posterior surfaces of the optics and the thick bulky haptics of these IOLs when placed entirely or partially in the sulcus.…”