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Marie-José Tassignon

Publications and source records attributed to Marie-José Tassignon.

11 recordsLinked to original sources
PubMed2006

Clinical comparison of 6 aberrometers. Part 2: statistical comparison in a test group.

PURPOSE: To compare and mutually validate the measurements of 6 aberrometers: the Visual Function Analyzer (Tracey), the OPD-Scan (ARK-10000, Nidek), the Zywave (Bausch & Lomb), the WASCA (Carl Zeiss Meditec), the MultiSpot Hartmann-Shack device, and the Allegretto Wave Analyzer. SETTING: University Hospital Antwerp, Antwerp, Belgium. METHODS: This prospective study was conducted on a group of 44 healthy eyes with refractions ranging from -5.25 diopters (D) to +5.25 D (cylinder 0 to -2 D). For each aberrometer and each eye, the averaged Zernike data were used to calculate various kinds of root-mean-square (RMS). These parameters, together with the refractive parameters, were then analyzed with a repeated-measures analysis of variance (ANOVA) test, complemented by paired t tests. A similar analysis was done for the comparison of the variances of these parameters. RESULTS: The aberrometers gave comparable values for all studied parameters with the following exceptions: The OPD-Scan underestimated the polynomials describing 4- and 5-fold symmetries, and the Visual Function Analyzer slightly overestimated the astigmatism terms. The 3rd-order radial RMS value was different for each device, as well as the RMS in the central 2.0 mm zone. The WASCA presented the lowest variance. CONCLUSION: These results suggest that in healthy eyes, all aberrometers produced globally similar results but they may vary in some details.

Adult↗
PubMed2006

Ring-shaped caliper for better anterior capsulorhexis sizing and centration.

We describe a new type of caliper to optimize the size, shape, and centration of the capsulorhexis during intraocular lens (IOL) surgery. This flexible, ring-shaped tool is positioned on the anterior capsule surface, where it is kept in place by an ophthalmic viscosurgical device. When in place, the caliper provides an ideal guide for the surgeon to follow and facilitates optimal capsulorhexis shape and centration.

Anterior Eye Segment↗
PubMed2006

One-year follow-up of bag-in-the-lens intraocular lens implantation in 60 eyes.

PURPOSE: To report the feasibility and clinical results of implanting a bag-in-the-lens intraocular lens (IOL) designed to prevent posterior capsule opacification after cataract surgery. SETTING: Departments of Ophthalmology, University of Antwerp, Antwerp, Belgium, and University of Munich, Munich, Germany. METHODS: This prospective study comprised 63 eyes (55 patients; 7 children, 48 adults) scheduled for cataract surgery and bag-in-the-lens IOL implantation. A posterior curvilinear capsulorhexis the same size as the anterior capsulorhexis was created for IOL insertion. After surgery, lens epithelial cell (LEC) proliferation was documented every 6 months with a minimum follow-up of 12 months. RESULTS: Sixty of 63 eyes (95%) had implantation of the bag-in-the-lens IOL. Conversion to a conventional IOL was necessary in 2 cases. In 1 eye, postoperative luxation of the IOL into the vitreous occurred as a result of an oversized anterior and posterior capsulorhexis. Three eyes had early postoperative iris incarceration in the lens groove that required surgery. No LEC proliferation on the optic occurred during a mean follow-up of 22.7 months (range 12 to 64 months); LEC proliferation was confined to the peripheral capsular bag. CONCLUSION: Lens epithelial cell proliferation was mild and confined to the periphery of the capsular bag during follow-up, and the bag-in-the-lens IOL optic remained clear.

Adolescent↗
PubMed2006

Cumulative neodymium:YAG laser rates after bag-in-the-lens and lens-in-the-bag intraocular lens implantation: comparative study.

PURPOSE: To study the cumulative neodymium:YAG (Nd:YAG) laser rate after bag-in-the-lens implantation (Morcher 89A) and lens-in-the-bag implantation (Morcher 92S) of 2 intraocular lenses (IOLs) of the same biomaterial. SETTING: Department of Ophthalmology, University Hospital of Antwerp, Edegem, Belgium. METHODS: This study comprised 100 eyes of 87 patients who had the bag-in-the-lens IOL implantation between January 2000 and August 2004. The postoperative follow-up ranged between 17 and 72 months. One hundred eyes of 94 patients of the same age and with the same follow-up period received the lens-in-the-bag IOL. The cumulative Nd:YAG laser frequency rates in both groups were calculated, and the cumulative incidence rates were defined by Kaplan-Meier survival analysis. RESULTS: No Nd:YAG laser capsulotomy was performed in eyes having bag-in-the-lens IOL implantation. A laser capsulotomy was performed in 20 eyes having lens-in-the-bag IOL implantation; the cumulative frequency in this group was 2% at 1 year and 20% at 71 months, with a plateau beginning at 42 months. The cumulative incidence rate of Nd:YAG posterior capsulotomy was approximately 2% at 1 year, increasing to approximately 28% at 42 months. CONCLUSIONS: The cumulative Nd:YAG laser rate after bag-in-the-lens implantation was zero. A zero rate has not been reported with lens-in-the-bag implantation of an IOL of the same biomaterial or of other biomaterials, as published in the literature. Thus, it can be concluded that the bag-in-the-lens implantation technique has 100% effectiveness against posterior capsule opacification.

Adolescent↗
PubMed2006

Contact lens-related corneal ulcers requiring hospitalization: a 7-year retrospective study in Belgium.

PURPOSE: To evaluate the clinical and epidemiological aspects of contact lens-related infectious corneal ulcers requiring hospitalization. METHODS: A retrospective analysis was performed on the files of patients hospitalized for contact lens-induced corneal ulcer in the eight Belgian university hospitals over a 7-year period (January 1997 to December 2003). Diagnoses for all hospitalized patients are obligatorily registered using the ICD-9 code. RESULTS: A total of 107 patients with contact lens-related corneal ulcers were documented: the number increased from five in 1997 to 22 in 2003. A total of 99 subjects used soft contact lenses, of whom nine used disposables, 73 planned replacement and 17 conventional lenses. Only six patients used extended wear lenses. Three patients used daily disposable lenses. The most frequently cultured organisms were Pseudomonas and other Gram-negative germs (70%) and Acanthamoeba (16%). The majority (77%) of the corneal ulcerations were centrally located and resulted in an average visual loss of four lines. CONCLUSION: During the study period, the number of patients hospitalized rose, which is only partially explained by the increasing prevalence of lens wearers: 3.5% and 6.5% of the Belgian population used lenses in 1995 and 2003, respectively. These factual data highlight the need for improvements in patient education.

Adolescent↗
PubMed2005

Clinical comparison of 6 aberrometers. Part 1: Technical specifications.

PURPOSE: To provide a detailed assessment of the techniques, technical features, and practical use of 6 aberrometers made available to our institution from September 2002 to January 2004. SETTING: Department of Ophthalmology, University Hospital Antwerp, Antwerp, Belgium. METHODS: A number of technical and practical parameters are listed for the Visual Function Analyzer (Tracey), the OPD-scan (ARK 10000; Nidek), the Zywave (Bausch & Lomb), the WASCA (Carl Zeiss Meditec), the MultiSpot Hartmann-Shack device, and the Allegretto Wave Analyzer including working principles, data acquisition, aberrometer alignment, wavefront calculation, and data analysis. Operator and patient comfort as well as practical advantages and disadvantages are discussed. CONCLUSION: All devices met at least half the following parameters: alignment, correction for source wavelength, data averaging, measurement quality check, and inhibition of accommodation.

Aberrometry↗
PubMed2004

Binocular vision impairment after refractive surgery.

PURPOSE: To illustrate the need for an accurate preoperative orthoptic examination to prevent postoperative changes in binocular vision. SETTING: Department of Ophthalmology, University Hospital Antwerp, Edegem, Belgium. METHODS: Five patients presenting major subjective complaints after refractive surgery were analyzed. RESULTS: In 1 patient, a latent N IV palsy decompensated after laser in situ keratomileusis (LASIK) in the more myopic eye to achieve monovision. A second patient, operated on for N IV palsy 10 years earlier, presented a recurrence of the palsy after bilateral LASIK for myopia. The third patient complained of discomfort in binocular vision caused by aggravation of a preexisting intermittent esotropia that worsened after LASIK for hyperopia. The fourth patient complained of diplopia after LASIK in the highly anisometropic and exotropic eye. The fifth patient experienced a decrease in fusion and stereopsis at the time he became anisometropic after bilateral LASIK. CONCLUSIONS: Special care should be taken of patients who have a preoperative history of strabismus surgery, an overcorrection or undercorrection in 1 or both eyes, or anisometropia and of those who are unhappy with contact lenses. An orthoptic examination should be done with and without spectacle correction to detect underlying vertical phorias. Intended monovision should be examined initially using contact lenses.

Adult↗
PubMed2004

[Geriatric eye diseases].

Ageing of the eye affects all ocular structures. Presbyopia is an early manifestation of physiological ageing resulting in the impossibility to read without additional spectacle correction. Some systemic disorders may interfere with the physiological ageing of the eye and cause blindness. In the western countries blindness is caused by age-related macular degeneration (26%), glaucoma (20.5%), cataract (11.2%), diabetic retinopathy (8.9%) and ischemic optic neuropathy (4 %).

Aged↗
PubMed2003

In vitro study on the closure of posterior capsulorrhexis in the human eye.

PURPOSE: An unexplained clinical observation is the development of posterior capsular opacification (PCO), even when the central part of the posterior capsule has been removed. The purpose of this study was to investigate in vitro the mechanisms involved in the closure of the posterior capsulorrhexis in a capsular bag model. METHODS: A sham extracapsular cataract extraction was performed in 71 human donor eyes, followed by a central posterior capsulorrhexis 3 to 4 mm in diameter. Each capsular bag was pinned to a PMMA ring with a central hole of 5 mm and placed in a Petri dish. The capsular bags were cultured and monitored for 3 to 7 weeks by phase-contrast microscopy, after which they were prepared for light, transmission, and scanning electron microscopy. RESULTS: Proliferation of lens epithelial cells (LECs) within the posterior rhexis area was found in 22 cases (31%) of which 3 had a complete closure. In the absence of the posterior capsule, a monolayer of LECs was observed growing on a basal lamina, consisting of loosely arranged fibers. Further observations on noncultured capsular bags revealed that this basal lamina corresponds to the anterior hyaloid membrane. CONCLUSIONS: This study corroborates the clinical observation that LECs that remain after cataract extraction have the potential to proliferate, in the absence of their natural substrate, on a basal lamina of vitreous origin and are able to close the posterior capsulorrhexis partially or totally in approximately one third of cases.

Adolescent↗
PubMedDate not supplied

A preliminary study on the prevention of posterior capsule opacification by photodynamic therapy with bacteriochlorin A in rabbits.

PURPOSE: Photodynamic therapy (PDT) with bacteriochlorin a (BCA) has proven to be successful in the treatment of cancers and to be cytocidal for lens epithelial cells (LECs) in culture. The present study aimed to determine whether PDT with BCA is also effective in destroying LECs in the capsular bag in vivo and could therefore be a strategy for prevention of posterior capsule opacification (PCO). MATERIALS AND METHODS: BCA was obtained by saponification and acid hydrolysis of bacteriochlorophyll a and was formulated in 30% polyethylene glycol, 20% ethanol and 50% water. Nine albino rabbits were anesthesized and both pupils dilated. Extracapsular lens extraction by phacoemulsification was performed on both eyes. One eye of each animal served as control. In the other eye, 1.5 ml BCA (10 or 50 microg/ml) was injected in the capsular bag and after 10 min, the eye was illuminated with a diode laser (wavelength 760 nm) for 10 or 15 min. Six weeks after surgery, the rabbits were sacrificed and the globes were enucleated, the capsular bags and the corneas removed, fixed and examined using stereomicroscopy and light microscopy. RESULTS: In the control capsular bags, extensive proliferation of LECs and formation of a complete ring of Soemmering was found, while in the PDT-treated capsular bags, LEC proliferation was markedly diminished and an incomplete irregular and much thinner ring of Soemmering was formed. Using the presently described application, the corneas of the PDT-treated animals were opaque and swollen and had lost their endothelial lining. CONCLUSION: PDT with BCA induces cell death in LECs and greatly reduces the formation of a ring of Soemmering. Therefore, it could be a promising novel means of prevention of PCO, provided the total length of the treatment can be substantially reduced and the negative effects on corneal transparency avoided.

Animals↗