Konrad Pesudovs

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https://hdl.handle.net/2328/989

Konrad Pesudovs is Foundation Professor and Chair of Discipline of Optometry and Vision Science at Flinders University. His main research interest is ophthalmology outcomes research; incorporating optical, visual and patient-centred measurement into the holistic measurement of outcomes in ophthalmology.

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Browsing Konrad Pesudovs by Subject "Corneal Topography"
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    Effect of cataract surgery incision location and intraocular lens type on ocular aberrations. [Post print]
    (Elsevier, 2005-04) Pesudovs, Konrad ; Dietze, Holger ; Stewart, Owen G ; Noble, Bruce A ; Cox, Michael J
    PURPOSE: To determine whether Hartmann-Shack wavefront sensing detects differences in optical performance in vivo between poly(methyl methacrylate) (PMMA) and foldable acrylic intraocular lenses (IOLs) and between clear corneal and scleral tunnel incisions and whether optical differences are manifested as differences in visual performance. SETTING: Department of Optometry, University of Bradford, West Yorkshire, United Kingdom. METHODS: This study comprised 74 subjects; 17 were phakic with no ocular pathology, 20 had implantation of a Pharmacia 722C PMMA IOL through a scleral tunnel, 21 had implantation of an Alcon AcrySof IOL through a scleral tunnel, and 16 had implantation of an AcrySof IOL through a corneal incision. Visual acuity and contrast sensitivity testing, ocular optical quality measurement using Hartmann-Shack wavefront sensing, and corneal surface measurement with a videokeratoscope were performed in all cases. RESULTS: There were significant differences between groups in the total root-mean-square (RMS) wavefront aberration over a 6.0 mm pupil (F=3.91; degrees of freedom=3,70; P<.05) mediated at the 4th-order RMS, specifically spherical and tetrafoil aberrations. The PMMA-scleral group had the least aberrations and the AcrySof-corneal group the most. For a 3.5 mm diameter pupil, the total higher-order RMS wavefront aberration was not significantly different between the groups (P>.05). There were no differences between groups in corneal shape, visual acuity, or contrast sensitivity. CONCLUSIONS: Implantation of the spherical PMMA IOL led to a slight reduction in total wavefront aberration compared to phakic eyes. AcrySof IOLs induced more aberrations, especially spherical aberration. Corneal-based incisions for IOL implantation compounded this increase. Studies of the optical performance of IOLs in vivo should use wavefront sensing as the main outcome measure rather than visual measures, which are readily confounded by multiple factors.
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    Orbscan mapping in Ehlers-Danlos syndrome [Post print]
    (Elsevier, 2004-08) Pesudovs, Konrad
    A candidate for refractive surgery presented with classic (type I) Ehlers-Danlos syndrome (EDS). Clinical examination revealed blue sclera, limbus-to-limbus corneal thinning, myopia, and astigmatism. Orbscan (Bausch & Lomb)pachymetry mapping provided a striking demonstration of the limbus-to-limbus thinning with a central corneal thickness of 360 microm in the right eye and 383 microm in the left eye and midperipheral corneal thickness ranging from 370 to 438 microm and 376 to 434 microm, respectively. Despite the theoretical biomechanical weakness from the thin cornea and defective collagen, regular surface topography was maintained without the development of keratoconus. Although all types of EDS remain a contraindication to laser refractive surgery, Orbscan mapping provides a valuable insight into corneal shape and thickness in this condition.