Scleral fixation of foldable acrylic intraocular lenses in aphakic post-vitrectomy eyes

Tetsuya Mutoh, Yukihiro Matsumoto, Makoto ChikudaDepartment of Ophthalmology, Dokkyo Medical University Koshigaya Hospital, Koshigaya, Saitama, JapanPurpose: To evaluate the outcome for scleral fixation of a foldable acrylic intraocular lens (IOL) in aphakic post-pars plana vitrectomy eyes for vitreoretinal disease.Methods: The medical records of 15 patients were reviewed. We evaluated such factors as the underlying vitreoretinal disease, preoperative expected refraction and postoperative actual refraction, best corrected visual acuity (BCVA), corneal endothelial cell density, and intraoperative and postoperative complications.Results: The most common cause of underlying vitreoretinal disease was retinal detachment, which was found in 8 cases. The mean refractive error was -0.10 diopters (D). The mean minimum angle of resolution (logMAR) values of BCVA were 0.27 preoperatively and 0.14 postoperatively. The mean corneal endothelial cell density was 2400 cells/mm2 preoperatively and 2187 cells/mm2 postoperatively. No significant differences were observed in either the logMAR values of BCVA or the corneal endothelial cell density before and after surgery. No intraoperative complications occurred in any of the patients. Postoperative complications occurred in a total of 7 eyes, and the most severe complications comprised 4 cases of transient ocular hypertension.Conclusion: The results for the scleral fixation of foldable acrylic IOLs were good in aphakic post-vitrectomy eyes.Keywords: scleral fixation, intraocular lens, aphakic post-pars plana vitrectomy eyes, severe vitreoretinal diseas

A case of iridoschisis associated with lens displacement into the vitreous cavity

We report the case of a 67-year-old woman with a lens that was displaced into the vitreous cavity in one eye and ipsilateral iridoschisis. She was free from a history of ocular trauma or of heritable ocular disease. Her best-corrected visual acuity was 1.2 bilaterally and right eye showed signs of iridoschisis. The corneal endothelial cell density decreased to 1,263 cells/mm2 in the right eye preoperatively. We speculated that iris tissue flowing in the anterior chamber might have intermittently touched the corneal endothelium. 25-gauge pars plana vitrectomy and lens removal were performed immediately. Free-floating iris tissue was cut during surgery with care not to injure the corneal endothelial cells. The postoperative progress was satisfactory and scleral fixation of an intraocular lens is planned. Iridoschisis is an uncommon cause of lens displacement into the vitreous cavity

Quantum Double-Torus

A symmetry extending the $T^2$-symmetry of the noncommutative torus $T^2_q$ is studied in the category of quantum groups. This extended symmetry is given by the quantum double-torus defined as a compact matrix quantum group consisting of the disjoint union of $T^2$ and $T^2_{q^2}$. The bicross-product structure of the polynomial Hopf algebra of the quantum double-torus is computed. The Haar measure and the complete list of unitary irreducible representations of the quantum double-torus are determined explicitly.Comment: 6 pages, no figures, amslatex, reformatted for Comptes Rendus, references added, typos and French correcte

Correlation between the matrix metalloproteinase-9 activity and chondroitin sulfate concentrations in tear fluid after laser in situ keratomileusis

Tetsuya Mutoh, Masaya Nishio, Yukihiro Matsumoto, Kiyomi Arai Department of Ophthalmology, Dokkyo Medical University Koshigaya Hospital, Koshigaya, Saitama, JapanAims: The aim of the present study was to evaluate the correlation between matrix ­metalloproteinase-9 (MMP-9) and chondroitin sulfate (CS) concentrations in human tear fluid following laser in situ keratomileusis (LASIK).Methods: Twelve eyes from six patients who had no ocular complaints except for ­refractive errors, and who had undergone LASIK, were enrolled in this study. We measured the ­concentrations of chondroitin 4 sulfate (C4S), chondroitin 6 sulfate (C6S), and MMP-9 activity with an enzyme-linked immunosorbent assay and an enzyme immunocapture activity assay preoperatively and postoperatively on days 1 and 4, week 1, and at 1 and 3 months.Results: Although the preoperative MMP-9 activity and the C4S concentration were highly correlated (r = 0.900; P < 0.001), they were not postoperatively correlated at month 1. Although the preoperative MMP-9 activity and the C6S concentration were highly ­correlated (r = 0.885; P < 0.001), they were not postoperatively correlated at either week 1 or months 1 and 3.Conclusions: The correlation appeared to be collapsed by LASIK, and it did not recover to the preoperative score at 3 months post-surgery. Our study indicates that the corneal wound healing was not terminated at 3 months following LASIK.Keywords: preoperative correlation, postoperative correlation, wound healing, refractive errors, human corne