EP2205960A1 - Procédé et dispositif de détermination réflectométrique précise de la densité optique du pigment maculaire xanthophylle sur le fond de l' il sans influence par de la lumière parasite - Google Patents

Procédé et dispositif de détermination réflectométrique précise de la densité optique du pigment maculaire xanthophylle sur le fond de l' il sans influence par de la lumière parasite

Info

Publication number
EP2205960A1
EP2205960A1 EP08802732A EP08802732A EP2205960A1 EP 2205960 A1 EP2205960 A1 EP 2205960A1 EP 08802732 A EP08802732 A EP 08802732A EP 08802732 A EP08802732 A EP 08802732A EP 2205960 A1 EP2205960 A1 EP 2205960A1
Authority
EP
European Patent Office
Prior art keywords
fundus
eye
light
illuminated
area
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP08802732A
Other languages
German (de)
English (en)
Inventor
Dietrich Schweitzer
Martin Hammer
Thomas Mohr
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Carl Zeiss Meditec AG
Original Assignee
Carl Zeiss Meditec AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Carl Zeiss Meditec AG filed Critical Carl Zeiss Meditec AG
Publication of EP2205960A1 publication Critical patent/EP2205960A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00—Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/12—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions for looking at the eye fundus, e.g. ophthalmoscopes
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B3/00—Apparatus for testing the eyes; Instruments for examining the eyes
    • A61B3/10—Objective types, i.e. instruments for examining the eyes independent of the patients' perceptions or reactions
    • A61B3/14—Arrangements specially adapted for eye photography
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B21/00—Microscopes
    • G02B21/06—Means for illuminating specimens
    • G02B21/08—Condensers
    • G02B21/082—Condensers for incident illumination only

Definitions

  • the invention relates to a method and a device for measuring the reflection light from the ocular fundus, the optical density of the macular pigment xanthophyll on the ocular fundus from the logarithmic quotient of the values of a compensation function and the reflection light measured in the macular region in monochromatic illumination of the ocular fundus with light in the absorption maximum of To calculate xanthophyll very exactly.
  • the macular pigment xanthophyll protects the macula, the area of the sharpest vision, from damage due to the absorption of the high-energy blue light. B. as a result of the formation of free radicals.
  • the macular pigment which mainly contains the hydroxy-substituted ß-carotenes lutein and zeaxantine, acts as a radical scavenger.
  • a low optical density of the macular pigment is a risk factor for the onset of age-related macular degeneration.
  • lutein and zeaxantine are not formed by the body, but must be ingested with food, it is necessary to determine the individual level of optical density of the macular pigment, in order to detect a possible hazard and derive any necessary supplementation of lutein and zeaxantine.
  • the optical density of Makulapigments is to be determined very accurately and free of interfering light, which arises in layers that are upstream of the object to be examined, especially the ocular fundus.
  • optical density of the macular pigment xanthophyll is important for the decision on the necessity and proof of the success of the aforementioned supplementation with lutein and zeaxantine, which is to be detected as an increase in the optical density of the macular pigment.
  • the compensation function virtually indicates the reflected light that would be reflected from the fundus in the area of the macula if no xanthophyll were present.
  • the logarithm of these quotients corresponds to the double optical density of the macular pigment (douple density) 2OD ⁇ of xanthophyll:
  • the optical density of the macular pigment is also overstated as the scattering increases with the 2-wavelength fluorescence method.
  • the age dependence of the xanthophyll optical density determined by means of Raman fluorescence measurements is essentially determined by the weakening of the excitation light as a result of the increasing scattering in the eye lens with age.
  • the invention is based on the object, even without compelling prerequisite of a laser scanning device, to be able to determine the optical density of the macular pigment xanthophyll on the ocular fundus without being influenced by stray light, in particular individually interfering stray light of the anterior ocular media, by refiectometric analysis.
  • the invention should also be applicable in fundus cameras.
  • the fundus in addition to the known measurement of the reflection light from illuminated areas of the fundus in a previous or subsequent step (possibly also simultaneously) the fundus is only partially illuminated and the intensity of the light is measured as stray light from a non-illuminated area of the fundus. From each pixel of light from the illuminated fundus, the stray light measured in the non-illuminated area of the fundus is subtracted. The compensation function is determined from the measured values corrected in each case for the stray light component from selected regions of the ocular fundus outside the macula.
  • the optical density of the macular pigment can be calculated according to equation (3): With:
  • I m u values of the reflection light in the macula area with illumination of the macular area, reduced by the values of the stray light, that of an unlit one Area of the fundus with partial illumination of the fundus.
  • a field stop is inserted into the illumination beam path for incident light detection, through which the observable ocular fundus is only partially illuminated, and a further insertable field stop is provided in the measurement beam path, which field is only used for the light to be measured as disturbance light from the unlit part of the field Ocular fundus is permeable, so that in this case only the remitted light from the specially unlighted (by the illumination in the illumination beam path) shadowed part of the ocular fundus is measured.
  • the invention can be used for all opthalmological devices based on the fundus camera principle for the reflectometric examination of the ocular fundus and does not necessarily require a confocal laser scanning principle.
  • a further, applicative improvement is obtained if the position of the field stop in the illumination beam path can preferably be adapted automatically to the defective vision of the patient.
  • a further improvement of the measurement may result if a corresponding filter in the observation beam path is provided for the suppression of interference light caused by autofluorescence of ocular tissue.
  • the distribution of the optical density of the macular pigment is evaluated with regard to its shape.
  • the invention will be explained in more detail below with reference to an ophthalmologic device shown in the drawing for the reflectometric determination of the optical density of the macaque lap polyanthophyll as an exemplary embodiment.
  • Fig. 1 Illumination of the fundus with a circular field and measurement of the light from the entire illuminated area.
  • FIG. 2 Illustration of an annular illumination field on the fundus of the eye centrally around the macula, wherein the area of the macula of approximately 2 degrees is not illuminated, but only light from this area is measured.
  • FIG. 3 shows a schematic 3D representation of the optical density of the macular pigment.
  • FIGS. 1 and 2 are based on the basic structure of a known ophthalmoscope with an illumination beam path 1 and a measurement beam path 2, which is used for eye examination.
  • a light source 3 with limited spectral range in the wavelength range of the absorption of the macular pigment xanthophyll is imaged in a known manner in the illumination beam path 1 via lenses 4 and 5 in the annular aperture Ap 1.
  • the aperture diaphragm AP 1 is imaged via a lens 6, a perforated mirror 7 and a further lens 8 in the aperture plane of the eye as an aperture diaphragm image AP 1 ', so that with the eye lens 9 a homogeneous illumination of the fundus 10 is realized.
  • a circular field stop FB 1 through which the fundus 10 via the lens 6, the hole mirror 7, the lens 8 and the lens 9 in a field FB 1 'preferably centrally around the Macula is illuminated in the spectral region in which xanthophyll absorbs.
  • a arranged in the focal plane of lens 8 in the measuring beam 2 circular field stop FB 2 allows for imaging by lenses 1 1 and 12, the radiation detection by a detector 13 of the entire circularly illuminated field of the fundus 10th
  • annular field stop FB 3 is arranged, which in the illumination beam path 1 via the lenses 5 and 6, the hole mirror 7, the lens 8 and the eye lens 9, an illuminated annular field FB 3 ' on the fundus 10 with an outer diameter of preferably 2.4 PD (diameter papilla) and an inner diameter of preferably 1.2 PD generated. It is essential that the field diaphragm 3 is designed so that the area of the macula, in which the optical density of the macular pigment xanthophyll is to be determined, is not illuminated in this case.
  • the illumination of the fundus 10 may also be as described in Fig. 1, but the macular area remains unlit.
  • a circular field stop FB 4 is arranged, which after the imaging of the fundus 10 via the eye lens 9 and the lens 8 only for a self-unlit field (macular) with a diameter of preferably 0.4 PD is permeable.
  • a circular aperture diaphragm AP 2 preferably in the focal plane of the lens 1 1, whose aperture diaphragm image AP 2 'is imaged on the eye lens 9, prevents in a known manner the detection of illumination light which is reflected on the anterior ocular media such as the eye lens 9.
  • the light imaged by a lens 12 onto the measuring field of a detector 13 from the normally unilluminated central field around the macula of the fundus 10 is mainly light which has been scattered several times in the anterior ocular media, predominantly in the ophthalmic lens 9. From the ocular fundus 10 diffusely reflected light entering the aperture diaphragm AP 2 'directly or by scattering in the eye lens 9 is also detected. Also multiple scattered fluorescent light, which was excited by the illumination in the eye lens 9 is also detected by this measurement. However, this fluorescent light is much weaker than the scattered illumination light.
  • the radiation which was measured at all pixels in the case of circular illumination of the ocular fundus 10 subtracts that radiation which is emitted when the ocular fundus 10 is illuminated annularly the non-illuminated field (in the present embodiment, the macular region of the fundus 10) was measured (see Fig. 2).
  • This light which is measured on the basis of the field stops FB 3 and FB 4 in the illumination or measuring beam path 1, 2 from the non-illuminated field of the fundus 10 (macular region) corresponds to the From the thus corrected values of the reflection light with complete illumination of the ocular fundus, the compensation function preferably becomes the annular region between 1.2 PD and 2.4 PD in a known manner certainly. This subtracts the scatter proportion in the numerator and denominator that interferes with equation (2). The optical density of the macular pigment is then calculated according to equation (3): With:
  • I Ak Values of the corrected compensation function, calculated from the values of the reflection light from areas outside the macula, reduced by the values of the disturbance light, which were obtained from an unlighted area of the fundus with partial illumination of the fundus, and
  • I n * values of the reflection light in the macular area with illumination also of the macular area, reduced by the values of the stray light, which were obtained from an unlighted area of the fundus with partial illumination of the fundus.
  • the field diaphragms FB 3 and FB 4 can each advantageously be arranged in the illumination or measuring beam path 1, 2 to be pivoted in and out (not shown in the drawing for reasons of clarity). It is also possible (also not shown in the figures) to execute the field apertures FB 2 and FB 4 as a single aperture with variable free diameter.
  • the shading diaphragm is preferably positioned in the illumination beam path to the conjugate plane of the patient retina.
  • a possibility for the automatic determination of the refractive error eg by means of autofocus is available. With the particular Value of the individual ametropia, the shading aperture is automatically adjusted to the defective vision.
  • Distortion light is to introduce into the observation beam a filter which blocks the light not originating from the fluorescence of the macular pigment.
  • Example of Xanthophyll would be a filter suitable, which light above 490nm
  • Wavelength suppressed For example, this filter could be near the position of
  • Field stop FB 2 or aperture AP 2 be provided. Alternatively, at
  • Realization of the detector 13 are read by a color camera only the blue pixels.
  • Accumulate fundus pigment such as lutein and zeaxantine, can also accumulate in the area outside the macula. In such a case, the evaluation area for the compensation function would be to increase or a correction is required.
  • the correction can preferably take place in that the optical density at the edge of
  • Evaluation area is compared.
  • Macula determines an averaged value of optical density and with an averaged one
  • the optical density at the edge of the evaluation area is higher than the reference value far outside the macula, the optical density of the fundus pigment will increase by the value of
  • a distribution of the macular pigment obtained as a result of the entire calculation is in
  • Fig. 3 ideally shown in 3D.
  • the border area it can also be a change in shape of the original circular
  • Diagnosis may thus benefit the calculation and display of a measure of the deviation from the circular structure.
  • this measure is determined in the range of average optical density to minimize noise effects.
  • This measure can be determined, for example, from the relationship between the enclosed area and the total length of the outer contour and compared with a normatively determined limit value in order to achieve a clarification of the diagnostic statement.
  • the optical density of the fundus pigment xanthophyll in the 3 D representation can deviate from a rotationally symmetric distribution with a certain variance.
  • the maximum of the optical density can occur, for example, at the edge of the distribution function.
  • a very locally limited but very high optical density can occur.
  • the display of a measure of the deviation from the rotationally symmetric structure is advantageous for the improved diagnosis.
  • a measure is calculated from the central moment of the second order (corresponding to the variance) and displayed to the user.
  • a measure of the central third-order moment (corresponding to the skewness) is calculated and displayed to the user.
  • This measure can be compared with a normatively determined limit and serve to clarify the diagnosis statement.
  • the determination of a statistical measure for the evaluation of the signal-to-noise ratio is advantageous.
  • a measure of the signal-to-noise ratio of the xanthophyll optical density is determined and compared with a normatively determined limit and serves the user to qualify the made Measurement.
  • the invention is not limited to the application for determining the optical density by means of the 1-wavelength reflection method, but also improves the accuracy in 2- or multi-wavelength methods for reflectometric xanthophyll determination at the fundus.

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  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Medical Informatics (AREA)
  • Biophysics (AREA)
  • Ophthalmology & Optometry (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Physics & Mathematics (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Eye Examination Apparatus (AREA)

Abstract

Procédé et dispositif de détermination réflectométrique précise de la densité optique du pigment maculaire xanthophylle sur le fond de l'œil sans influence par de la lumière parasite, notamment par diffusion individuelle de lumière dans les milieux oculaires avant. L'invention vise à pouvoir déterminer également par réflectométrie la densité optique du pigment maculaire xanthophylle sur le fond de l'œil sans influence par de la lumière parasite, notamment par de la lumière diffuse individuellement perturbatrice des milieux oculaires avant. Selon l'invention, en plus de mesurer la lumière réfléchie issue de zones éclairées du fond de l'œil, ces zones ne sont que partiellement éclairées et on mesure l'intensité de la lumière parasite issue de la zone non éclairée. Cette valeur de mesure sert de grandeur de correction pour calculer la densité optique du pigment maculaire. L'invention est appliquée en ophtalmologie.
EP08802732A 2007-10-02 2008-10-01 Procédé et dispositif de détermination réflectométrique précise de la densité optique du pigment maculaire xanthophylle sur le fond de l' il sans influence par de la lumière parasite Withdrawn EP2205960A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102007047300A DE102007047300A1 (de) 2007-10-02 2007-10-02 Verfahren und Vorrichtung zur genauen reflektometrischen Bestimmung der optischen Dichte des Makulapigments Xanthophyll am Augenhintergrund ohne Beeinflussung durch Störlicht, insbesondere durch individuelle Lichtstreuung in den vorderen Augenmedien
PCT/EP2008/008315 WO2009046912A1 (fr) 2007-10-02 2008-10-01 Procédé et dispositif de détermination réflectométrique précise de la densité optique du pigment maculaire xanthophylle sur le fond de l'œil sans influence par de la lumière parasite

Publications (1)

Publication Number Publication Date
EP2205960A1 true EP2205960A1 (fr) 2010-07-14

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EP08802732A Withdrawn EP2205960A1 (fr) 2007-10-02 2008-10-01 Procédé et dispositif de détermination réflectométrique précise de la densité optique du pigment maculaire xanthophylle sur le fond de l' il sans influence par de la lumière parasite

Country Status (3)

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EP (1) EP2205960A1 (fr)
DE (1) DE102007047300A1 (fr)
WO (1) WO2009046912A1 (fr)

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WO2011076943A2 (fr) * 2009-12-23 2011-06-30 University College Dublin, National University Of Ireland, Dublin Systèmes d'imagerie rétinienne à résolution améliorée
DE102012007113A1 (de) 2012-04-04 2013-10-10 Carl Zeiss Meditec Ag Verfahren zur Bestimmung mindestens eines Parameters zur Diagnose oder Risikobewertung einer Erkrankung, insbesondere des Risikos einer Erkrankung an AMD
EP2668894A1 (fr) 2012-05-30 2013-12-04 National University of Ireland, Galway Systèmes et procédés d'imagerie du fond de l'ýil
DE102013008532A1 (de) 2013-05-17 2014-11-20 Carl Zeiss Meditec Ag Verfahren zur Realisierung streulichtkorrigierter Fundusaufnahmen eines Auges
ES2653913B1 (es) * 2016-07-06 2019-01-04 Univ Murcia Instrumento óptico para la medida de la densidad del pigmento macular en el ojo y método asociado
DE102018107625A1 (de) * 2018-03-29 2019-10-02 Imedos Systems GmbH Vorrichtung und Verfahren zur Untersuchung der retinalen vaskulären Endothelfunktion
DE102018111769B4 (de) * 2018-05-16 2020-03-26 Technische Universität Ilmenau Vorrichtung und Verfahren zur Elimination des Einflusses vorgelagerter Schichten bei spektralen Messungen an geschichteten Objekten
GB2577299B (en) * 2018-09-21 2022-09-14 Res & Innovation Uk Method and apparatus for determining a scattering spectrum of an eye
CN115712363A (zh) * 2022-11-21 2023-02-24 北京中科睿医信息科技有限公司 界面色彩显示方法、装置、设备及介质

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DE4410690C1 (de) * 1994-03-28 1995-06-29 Univ Schiller Jena Anordnung zur spektrometrischen Untersuchung und deren Verwendungen
DE4433827C2 (de) * 1994-09-22 1999-01-07 Zeiss Carl Jena Gmbh Anordnung und Verfahren zur Messung von Stoffparametern in Schichten von Medien, insbesondere zur eichungsfreien in vivo Messung der Sauerstoffsättigung in optisch zugängigen Blutgefäßen
DE10129652B4 (de) 2001-06-15 2018-01-04 Carl Zeiss Jena Gmbh Anordnung und Verfahren zur Bestimmung der zweidimensionalen Verteilung von Funduspigmenten, insbesondere des Makulapigments Xanthophyll
DE102004042198A1 (de) 2004-08-26 2006-03-02 Friedrich-Schiller-Universität Jena Verfahren und Vorrichtung zur Trennung und genauen Bestimmung lokal wirksamer Fluorophore eines Objektes
DE102004042197A1 (de) * 2004-08-26 2006-03-02 Friedrich-Schiller-Universität Jena Verfahren und Vorrichtung zur genauen selektiven Bestimmung lokal wirksamer Fluorophore eines Objektes
DE102005058185A1 (de) 2005-12-01 2007-06-14 Friedrich-Schiller-Universität Jena Verfahren und Anordnung zur Detektion von Fluoreszenz- oder Reflexionsspektren beliebig wählbarer Bereiche und Strukturen eines vom Fremdlicht überlagerten Objekts unter geringer Strahlenbelastung
DE102007025425A1 (de) 2007-05-30 2008-12-04 Friedrich-Schiller-Universität Jena Verfahren und Vorrichtung zur Eliminierung störender Fluoreszenz bei der Fluoreszenzauswertung von Objekten, beispielsweise des Augenhintergrundes

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Also Published As

Publication number Publication date
WO2009046912A1 (fr) 2009-04-16
DE102007047300A1 (de) 2009-04-09

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