Square-edge intraocular lenses and epithelial lens cell proliferation: implications on posterior capsule opacification in an in vitro model.

BACKGROUND: To evaluate lens epithelial cell (LEC) proliferation with two different designs (one-piece or three-piece) of hydrophobic acrylic IOLs with 360° square optic edge using an in vitro culture model of posterior capsule opacification (PCO). METHODS: This experimental study was conducted at the Department of NEUROFARBA, Section of Pharmacology, University of Florence, Italy. Human LECs were seeded and cultured in transwell cell culture inserts coated with a type-IV collagen membrane on which an IOL (one-piece Tecnis-1 or three-piece AR40E, Abbott Medical Optics Inc.) had been previously placed. As control, cells were plated on the insert membrane without an IOL. At day six (cells confluent in controls) IOLs were removed and cell counting, viability and cell density under and outside the IOLs were evaluated. RESULTS: No statistically significant difference in the number of cells (p>0.05) between inserts with the one-piece and three-piece IOLs was found. Cell density in the area under each IOL was significantly lower than in the area outside of it (p<0.05), or in the control insert. (p<0.05). Cell density under the single-piece IOL was not significantly different from that under the three-piece IOL (p>0.05). CONCLUSIONS: A 360° sharp-edge played a crucial role in avoiding LEC migration under the IOL and preventing the formation of PCO after cataract surgery. Long term clinical evaluation is necessary to estimate functional results.

Subjective through-focus quality of vision with various versions of modified monovision.

BACKGROUND/AIMS: To evaluate and compare the effect of various modified monovision on binocular through-focus quality of vision. METHODS: Simulated images were computed using a numerical eye model, with a 4.7 mm pupil diameter, for various target vergences and with various combinations of spherical (SA4) and secondary spherical (SA6) aberrations. Binocular vision was provided using a video projector synchronised with active glasses. Three subjects evaluated monocular and binocular through-focus images by scoring the displayed image with a five-item continuous grading scale. Performance was evaluated in terms of depth-of-focus and area under the through-focus subjective quality of vision curves (AUC). RESULTS: On average, viewing through a combination of 0.4 µm of SA4 and -0.2 µm of SA6 with one eye and through a combination of -0.4 µm of SA4 and 0.2 µm of SA6 with the other eye, improved depth-of-focus and AUC, respectively, by 193% and 71% compared with naked eyes. Binocular summation occurred when both eyes viewed comparable image quality, whereas the level of binocular inhibition increased with the interocular difference of image quality. CONCLUSIONS: Binocular performance could be optimised by choosing different multifocal profiles for each eye and by adding a defocus term between eyes.

Pharmacokinetic evaluation of diquafosol tetrasodium for the treatment of Sjögren's syndrome.

INTRODUCTION: Dry eye is a multifactorial disease of the ocular surface causing ocular discomfort and visual impairment for the patient. A variety of topical and systemic drugs are available to treat dry eye. Conventional treatments are limited to tear supplementation or improvement of ocular surface inflammation by the use of corticosteroids or cyclosporine A. Treatment of severe dry eye associated with Sjögren's syndrome (SS) is even more challenging and is designed to improve the quality and quantity of tear fluid. Diquafosol tetrasodium , a P2Y2 purinergic receptor agonist, acts via a novel mechanism by activating P2Y2 receptors of the ocular surface. AREAS COVERED: The aim of this review is to summarize the pharmacokinetics, and pharmacological and clinical data of 3% diquafosol tetrasodium ophthalmic solution in patients with dry eye, particularly SS. The mechanisms of impaired ocular surface due to severe dry eye, as defined by the International Dry Eye Workshop, are analyzed. EXPERT OPINION: Diquafosol tetrasodium provides a novel mode of action in dry eye syndrome, including SS, by stimulating the quantity and quality of tear fluid secretion via various mechanisms. In clinical trials, 3% Diquafosol tetrasodium ophthalmic solution demonstrated a good safety profile and exhibited efficacy with clinical improvement of the ocular surface in dry eye including SS.

Astigmatism correction with toric intraocular lenses: wavefront aberrometry and quality of life.

BACKGROUND/AIM: To evaluate wavefront aberrations and subjective quality of life after toric intraocular lens (TIOL) implantation. METHODS: Three groups of subjects who underwent unilateral cataract surgery with intraocular lens (IOL) implantation were compared: (1) toric group (n=40): corneal astigmatism >1.50 D, implanted with Acrysof toric SN60TT IOL (Alcon Inc, Fort Worth,  Texas, USA); (2) astigmatic SN60AT group (n=40): corneal astigmatism >1.50 D, implanted with Acrysof SN60AT IOL; and (3) control group (n=40): corneal astigmatism <1.00 D, implanted with Acrysof SN60AT IOL. Uncorrected distance visual acuity (UDVA), refraction, lower order astigmatism (Z(2)2, Z(-2)2), Strehl ratio and the modulation transfer function area ratio were evaluated over a 3 month follow-up period. A standardised quality of life test (National Eye Institute Refractive Error Quality of Life Instrument-42) was distributed to both astigmatic groups 3 months postoperatively. RESULTS: Postoperative UDVA and aberrometric values were significantly better (p<0.001) and mean postoperative spherical equivalent was significantly lower (p<0.05) in the toric and control groups compared with the astigmatic SN60AT group. The toric group had significantly better postoperative quality of life compared with the astigmatic SN60AT group (p<0.05). CONCLUSIONS: Acrysof TIOL implantation resulted in better visual, refractive and aberrometric results than SN60AT spherical IOL implantation in astigmatic patients, similar to the control group. The better objective optical and retinal image quality resulted in better subjective quality of life after TIOL implantation.

Epidermal growth factor variations in amniotic membrane used for ex vivo tissue constructs.

INTRODUCTION: The amniotic membrane (AM) is used for engineering ex vivo tissue constructs used in ocular surface reconstruction. Epidermal growth factor (EGF) content of the AM is believed to play a key role in supporting corneal epithelial cell expansion on AM. This study investigated EGF content in AM in relation to intra- and inter-donor variations and the effect of processing and preservation (handling). METHODS: Fifteen human AM, both fresh and handled, were analyzed for EGF gene and protein expression by real-time polymerase chain reaction and ELISA, respectively. RESULTS: EGF gene expression was predominantly seen in the AM epithelium (p<0.01). Similarly, EGF protein too was predominantly seen in the epithelial layer (p<0.01) for fresh and handled samples. EGF protein content varied between membranes (inter-donor) and at different sites within the same membrane (intra-donor). The highest EGF protein concentration was noted in the AM apical and mid-region epithelium. Significant EGF protein loss (p<0.01) was observed after handling. CONCLUSION: There is a considerable variation in EGF content between and within donors. This is further affected by handling of the AM. Such variations could affect the clinical efficacy of tissue constructs. Current use of AM for ex vivo expansion of epithelial cells is not standardized and remains an area of concern.

The use of impression cytology in the follow-up of severe ocular burns.

AIMS: To evaluate by impression cytology (IC) the expression of the MHC class II inflammatory marker HLA-DR by the conjunctival epithelium, the cytological modifications of the conjunctival surface according to the Nelson's classification, and the eventual correlation between the two after severe ocular burns. METHODS: A total of 24 patients (24 eyes) who presented with severe ocular burns underwent IC. We compared them with 18 healthy eyes. HLA-DR expression was studied by flow cytometry as well as the conjunctival histology evaluated with the Nelson's classification from 2-24 months after the onset of burns. RESULTS: There was a significant upregulation of the expression of HLA-DR in eyes with burns compared to the healthy population at 2 months (p<0.001), 6 months (p<0.001), 12 months (p = 0.019), 18 months (p = 0.0171) and 24 months (p = 0.01766). A significant difference was found between the Nelson grade in the pathological population and those of the healthy population at 2 months (p = 0.0157). HLA-DR upregulation was significantly correlated with the Nelson's grades between 2 months (r = 0.69, p<0.0001) and 6 months (r = 0.61, p = 0.0001). CONCLUSION: The IC technique can act as a useful tool for following-up ocular surface inflammation after severe ocular burns.

Ultrasound biomicroscopy study of the Verisyse aphakic intraocular lens combined with penetrating keratoplasty in pseudophakic bullous keratopathy.

PURPOSE: To evaluate anterior segment modifications after penetrating keratoplasty (PKP), previous anterior chamber intraocular lens (IOL) removal, and Verisyse IOL (AMO) implantation over the iris or under the iris for the treatment of pseudophakic bullous keratopathy (PBK) using ultrasound biomicroscopy. SETTING: Department of Ophthalmology, Poitiers University Hospital, Poitiers, France. METHODS: A prospective randomized comparative case series included 27 patients (27 eyes) with PBK who had PKP and implantation of a Verisyse VRSA54 aphakic IOL. The IOL was implanted over the iris in 13 patients (Group A) and under the iris in a reversed position in 14 patients (Group B). Ultrasound biomicroscopy scans 6 months after surgery measured central anterior chamber depth (ACD), iris thickness (IT), distance of the haptics from the corneal endothelium (CED), distance of the haptics from the ciliary body (CBD), angle opening distance (AOD) 500 mum from the scleral spur (AOD500) and the iridocorneal angle theta on the 4 o'clock meridian lines (AOD3; AOD9; AOD12; AOD6/theta12, theta6, theta3, theta9). RESULTS: No significant difference was found in IT, CBD, or AOD12 between Group A and Group B (P >.05). In Group B, the mean ACD was deeper by approximately 55% (P = .008); CED3 was larger by 69% (P = .0162), CED9 by 80% (P = .0128), AOD3 by 57% (P = .0309), AOD9 by 140% (P = .0057), and AOD6 by 44% (P = .0399); and theta3 was wider by 52% (P = .046), theta9 by 123% (P = .0068), theta12 by 50% (P = .0492), and theta6 by 81% (P = .0237). CONCLUSION: Ultrasound biomicroscopy showed that in eyes that had PKP with Verisyse IOL enclavation to the posterior plane of the iris, which involved posterior translation of the iridal plane, the ACD was significantly deeper and the CED and AOD were significantly larger than in eyes with anterior enclavation of the IOL.

Amniotic membrane transplantation in severe bacterial keratitis.

PURPOSE: To determine whether a combination of early amniotic membrane transplantation (AMT) and early topical corticosteroid treatment could be a safe adjuvant therapy during antibacterial treatment in severe bacterial keratitis (BK) for relieving pain, avoiding iatrogenic epithelial toxicity, and allowing earlier use of topical steroids. METHODS: In a prospective noncomparative case series, 12 patients with severe microscopically-proven BK were treated with immediate maximal topical antibiotics followed by AMT at 48 hours (single-layer epithelial side-down or multilayer epithelial side-up), plus topical steroid treatment at 72 hours. Pain relief (NRS-11 numeric rating pain scale) and the corneal epithelium healing were measured. RESULTS: The follow-up rate was 7.5 person-months, with AMT performed once in 2 patients and twice in 10 patients with BK caused by Pseudomonas aeruginosa (5), Klebsiella pneumoniae (1), Moraxella cattharalis (1), Staphylococcus aureus (1), Staphylococcus epidermidis (2), or Streptococcus pneumoniae (1). A significant decrease in the pain score was noted from the admission day (median, 8; range, 7-10) to shortly after AMT (at day 3: median, 2; range, 1-3). Epithelial healing was achieved between 8 and 45 days (mean, 25.5 +/- 9.7 days). Neither perforation nor neovascularization was observed. CONCLUSIONS: Early AMT combined with topical corticosteroid in severe BK provides immediate pain relief and allows epithelial healing.

Penetrating keratoplasty combined with posterior Artisan iris-fixated intraocular lens implantation.

PURPOSE: To present a new surgical technique combining penetrating keratoplasty and open-sky posterior iris fixation of the Artisan iris-claw intraocular lens (IOL) for treatment of pseudophakic bullous keratopathy in a case series of five patients. METHODS: A graft diameter of 8.25 mm was chosen. The formerly implanted angle-supported IOL was removed. The IOL was enclosed, entrapping a fraction of the mid-peripheral iris within the haptics whilst being held firmly with the implantation forceps. The corneal button was sutured to the recipient bed with 10-0 nylon sutures. A specular microscope was used for making an endothelial cell count. Patients underwent an ultrasound biomicroscope (UBM) scan before and 6 months after surgery and postoperative macular oedema was assessed by optical coherence tomography (OCT). The minimum follow-up was 12 months. RESULTS: Visual acuity (VA) improved in all five cases (mean best corrected VA was 0.4 postoperatively versus 1.28 preoperatively). No complications were noted. The mean endothelial cell density obtained after 1 year was 1508 cells/mm(2). The UBM study showed a deep anterior chamber and an open iridocorneal angle of 360 degrees in all cases. CONCLUSION: The implantation of the Artisan device behind the iris better preserves the anatomy of the anterior segment with respect to the iridocorneal angle.

Optic neuropathy in refractory neurosarcoidosis treated with TNF-alpha antagonist.

CASE REPORT: To report a rare case of optic neuropathy in refractory neurosarcoidosis treated with tumour necrosis factor-alpha antagonist (infliximab) perfusion. A 41-year-old man with diabetes presented with an abrupt, painless, unilateral visual loss. Thoracic computed tomography disclosed mediastinal lymphadenopathy, and evidence from histopathology confirmed sarcoidosis. COMMENTS: Corticosteroids alone and with immunosuppressive agents failed to suppress the active disease. Alternative therapy of infliximab perfusions resulted in disease remission and relative visual improvement, and this treatment may warrant further clinical studies.

Retinal angioma in a patient with Cowden disease.

PURPOSE: To report a rare case of ocular localization of Cowden disease. DESIGN: Case report. METHODS: A 50-year-old woman with a history of multiple tumors was diagnosed with Cowden disease. A PTEN gene mutation was found. Visual acuity of the left eye had decreased 2 years before diagnosis. RESULTS: Visual acuity was 20/20 in the right eye and 20/200 in the left eye. Right eye fundus examination showed an epiretinal membrane associated with a peripheral and temporal inferior angiomatous lesion. Treatment consisted of cryoapplication and surgical removal of the epiretinal membrane after central vitrectomy. Although the anatomic result was satisfactory, the patient's visual acuity remained unchanged. CONCLUSIONS: Hamartomatous ocular lesions have been described in Cowden disease. We are unaware, however, of such retinal angiomatous lesions in patients with PTEN gene mutations.