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Observation of pre-corneal tear film using an anterior eye segment analysis system
‘lhesday, 5:30-790
X ICER Abstracts
P.M., Sep 22, 1992 Palazzo Dei Congressi 351
43
LABORATORY DISEASE Department
STUDIES of Ophthalmology,
OF HERPES Bristol
SIMPLEX Eye Hospital,
KERATITIS Bristol,
NORMAN F BUTTON BSc(Hons) DEPARTMENT OF OPTOMETRY GLASGOW POLYTECHNIC COWCADDENS ROAD GLASGOW G4 OBA
RECURRENT England.
We have recently developed a unique moose model for tbe study of recurrent herpetic eye diseaw This model embodii a co&derable experimental advance since previous investigators wing thin animal, despite achieving reactivation in the ganglion and shedding of virus, have failed to demonstrate clinical disease. Compared to models of recurrent diseasa in rabbits (where no inbred strains or appropriate monoclonal anribodles are available) our system can be used for detailed immunological analysis.
DURING
352
44 NORMAN F BUTTON BSc(Hons) DEPARTMENT OF OPTOMETRY GLASGOW POLYTECHNIC COWCADDENS ROAD GLASGOW G4 OBA SCOTLAND
EXPFZ+I-
L&den,
Each keratitis u&s induced in Chincilla rabbits by intracorneal injection with PO ~1 of 20% human serum albumin (immunogenic keratitis) or with 20 ~1 of clove oil (toxic keratitis). After 17 days in immunogenic keratitis 01 56 hours in toxic keratitis when leukocyte infiltration in the cornea was evident, cornea and iris were removed after death of the animals and incubated during several hours in vitro for production of lipid mediators. Prostaglandin E2 and platelet activating factor (PAF) were produced in greater amounts by the eye tissues in toxic keratitis than in irmnunogenic keratitis. Production of leukotriens B4 and C4 by the cornea was greater in immunogenic keratitis than in toxic keratitis, whereas the production of these leukotriens by the iris was not markedly changed in both keratitis states.
42
FOR
This paper describes theoretically and with practical application a method of displaying three-dimensional SOUI‘CB data. The primary application is the cornea1 surface topography although reference is made to other common ocular data such as stimulus luminance thresholds The primary function of the technique is in the display of three-dimensional data from stereophotogrammetric evaluation of cornea1 topography. The technique is developed to show its flexlbllity using difference and differential plotting methods. These techniques are applied to a number of common clinical situations such as keratoconus, pteryglum, cornea1 dIstortIon, astigmatigr and abrasion. Similar representations of retinal sensitivity are demonstrated using luminance threshold data. The use of difference and differential plotting techniques have been evaluated in an attempt to provide an early warning indicator of sub-clInica changes prior to manifest tissue structural alterations.
349
41
FBCO DCLP SCIENCE
THE USE OF COMPUTER ASSISTED DRAWING TECHNIQUES THREE-DIMENSIONAL CORNEAL SURFACE VISUALISATION
In our model, primary ocular infection was induced under cover of passive immunisation. In the majority of mice, this treatment protected the eye from damage (a normal sequel to infection in unimmunisad animals) without interfering with the establishment of latency in the trigeminal ganglion. After the primary infection, animals were treated with immunwuppressants and UV irradiation or UV irradiation alone. Mice were examined for signs of reCurrent disease, eyewashings were taken for the isolation of virus and, on occasions, epithelial sheets were stained for virus antigens. After either treatment, virus was recovered from the tear film and dendritic or geographic ulceration of the cornea was seen. These closely resembled the herpetic lesions seen in man. There was excellent correlation between the pattern and distribution of recurrent cornea1 disease and the distribution of cells containing virus antigens in cornea1 epithelial sheets.
PRODUCTION OF LIPID MEDIATORS BY CORNEA ANl! IRIS MENTAL KERATITIS IN RABBITS. van Delft J.L., van Haerin.qen N.J., Radder C.M. Department of Ophthalmology, University of Leiden, The Netherlands
AND
PhD VISION
AND
PhD VISION
FBCO DCLP SCIENCE
ARE HIGH DK CONTACT LENS MATERIALS NECESSARY FOR HEALTH IN DAILY WEAR RIGID GAS PERMEABLE LENSES?
CORNEAL
Attempts to satisfy the physiological demands of the cornea has lead to the development of an extensive range of gas permeable materials. The choice of the most suitable material therefore requires that a clinical method for determining individual cornea1 metabolic demands should be available. Evaluation of physiologica: discrimlnants by factor and discriminant analysis identlfled the most efficient predictors as being oxygen uptake rate, tear glucose and sodium ion concentration. The contribution of the barrier effects of deposits, tear film and media interfaces were applied to the prediction equations to derive a second generation predictor which was tested in clinical trial. Predictiod equations, weighted by discriminant coefficients, enablea the most suitable lens materials to be assigned in individual cases. A double-blind trial on 170 subjects (340 eyes) was conducted to assess the efficacy of the predictlan method. Patients were assigned at random to either the "Predictor" or the "Highest" DK group. Each group was evaluated over a period of 4 years to determine the Incidence of metabolic related adverse reactions using accepted clinical signs. The groups were compared statistically. 45
350
353
OBSERVATIONOF PRE-CORNEA1TEAR FILM USING AN ANTERIOR EYE SECMRNTANALYSIS SYSTEM Kazuyuki Sasaki. Kazuko Kitagawa.Yasuo Sakamoto Department of Ophthalmology. Kanazawa Medical University, Uchinada. JAPAN
UL.TFIASTRUCTUti'CIL STUDY ON HUllAN CORNEA TRATED WITH f:‘HClTOTEf?fWEUTIC k ERATECTOMY A LOFFREDO E VEIX’HIONE M DEL.UTA E LLOFFKEDC -I--------I-L--11----1-:------1-1-------.M. LOFFREDD k,. I- ,, , . Depar-tmwt ef Ophthalmolo~~y !Jnlvri-<
Pre-cornea1 tear film was observed utilizing an image analysis technique. For this purose an anterior eye sequent analysis system (NIDEK EAS-MID). which was developed by the authors’ eroup. was applied. After instillation of 1 ~1 of 2!4 fluorescein sodium into the cul-de-sac. the anterior eye segment was doctuuented with EAS-1000 through exciting and barrier filters which are the same as those used in fluorescein fundus angiography. Documentation was performed every three minutes until the 15th minute. The intensity of fluorescence (1.F.). which was measured by densitometry was applied as an indicator of tear fluid clearance. The I.F. of normal volunteers was compared with those of patients with dry eyes and contact lens wearers. In normal cases. pre-cornea1 fluorescence was measurable up to 6th~-9th rsinute. The methnd applied in this clinical study will be useful for evaluation of tear fluid clearance. A correlation between tha data obtained from this method and those of conventional methods will also be presented.
s.105
Naples E30lBl
X ICER Abstracts
P.M., Sep 22, 1992 Palazzo Dei Congressi 351
43
LABORATORY DISEASE Department
STUDIES of Ophthalmology,
OF HERPES Bristol
SIMPLEX Eye Hospital,
KERATITIS Bristol,
NORMAN F BUTTON BSc(Hons) DEPARTMENT OF OPTOMETRY GLASGOW POLYTECHNIC COWCADDENS ROAD GLASGOW G4 OBA
RECURRENT England.
We have recently developed a unique moose model for tbe study of recurrent herpetic eye diseaw This model embodii a co&derable experimental advance since previous investigators wing thin animal, despite achieving reactivation in the ganglion and shedding of virus, have failed to demonstrate clinical disease. Compared to models of recurrent diseasa in rabbits (where no inbred strains or appropriate monoclonal anribodles are available) our system can be used for detailed immunological analysis.
DURING
352
44 NORMAN F BUTTON BSc(Hons) DEPARTMENT OF OPTOMETRY GLASGOW POLYTECHNIC COWCADDENS ROAD GLASGOW G4 OBA SCOTLAND
EXPFZ+I-
L&den,
Each keratitis u&s induced in Chincilla rabbits by intracorneal injection with PO ~1 of 20% human serum albumin (immunogenic keratitis) or with 20 ~1 of clove oil (toxic keratitis). After 17 days in immunogenic keratitis 01 56 hours in toxic keratitis when leukocyte infiltration in the cornea was evident, cornea and iris were removed after death of the animals and incubated during several hours in vitro for production of lipid mediators. Prostaglandin E2 and platelet activating factor (PAF) were produced in greater amounts by the eye tissues in toxic keratitis than in irmnunogenic keratitis. Production of leukotriens B4 and C4 by the cornea was greater in immunogenic keratitis than in toxic keratitis, whereas the production of these leukotriens by the iris was not markedly changed in both keratitis states.
42
FOR
This paper describes theoretically and with practical application a method of displaying three-dimensional SOUI‘CB data. The primary application is the cornea1 surface topography although reference is made to other common ocular data such as stimulus luminance thresholds The primary function of the technique is in the display of three-dimensional data from stereophotogrammetric evaluation of cornea1 topography. The technique is developed to show its flexlbllity using difference and differential plotting methods. These techniques are applied to a number of common clinical situations such as keratoconus, pteryglum, cornea1 dIstortIon, astigmatigr and abrasion. Similar representations of retinal sensitivity are demonstrated using luminance threshold data. The use of difference and differential plotting techniques have been evaluated in an attempt to provide an early warning indicator of sub-clInica changes prior to manifest tissue structural alterations.
349
41
FBCO DCLP SCIENCE
THE USE OF COMPUTER ASSISTED DRAWING TECHNIQUES THREE-DIMENSIONAL CORNEAL SURFACE VISUALISATION
In our model, primary ocular infection was induced under cover of passive immunisation. In the majority of mice, this treatment protected the eye from damage (a normal sequel to infection in unimmunisad animals) without interfering with the establishment of latency in the trigeminal ganglion. After the primary infection, animals were treated with immunwuppressants and UV irradiation or UV irradiation alone. Mice were examined for signs of reCurrent disease, eyewashings were taken for the isolation of virus and, on occasions, epithelial sheets were stained for virus antigens. After either treatment, virus was recovered from the tear film and dendritic or geographic ulceration of the cornea was seen. These closely resembled the herpetic lesions seen in man. There was excellent correlation between the pattern and distribution of recurrent cornea1 disease and the distribution of cells containing virus antigens in cornea1 epithelial sheets.
PRODUCTION OF LIPID MEDIATORS BY CORNEA ANl! IRIS MENTAL KERATITIS IN RABBITS. van Delft J.L., van Haerin.qen N.J., Radder C.M. Department of Ophthalmology, University of Leiden, The Netherlands
AND
PhD VISION
AND
PhD VISION
FBCO DCLP SCIENCE
ARE HIGH DK CONTACT LENS MATERIALS NECESSARY FOR HEALTH IN DAILY WEAR RIGID GAS PERMEABLE LENSES?
CORNEAL
Attempts to satisfy the physiological demands of the cornea has lead to the development of an extensive range of gas permeable materials. The choice of the most suitable material therefore requires that a clinical method for determining individual cornea1 metabolic demands should be available. Evaluation of physiologica: discrimlnants by factor and discriminant analysis identlfled the most efficient predictors as being oxygen uptake rate, tear glucose and sodium ion concentration. The contribution of the barrier effects of deposits, tear film and media interfaces were applied to the prediction equations to derive a second generation predictor which was tested in clinical trial. Predictiod equations, weighted by discriminant coefficients, enablea the most suitable lens materials to be assigned in individual cases. A double-blind trial on 170 subjects (340 eyes) was conducted to assess the efficacy of the predictlan method. Patients were assigned at random to either the "Predictor" or the "Highest" DK group. Each group was evaluated over a period of 4 years to determine the Incidence of metabolic related adverse reactions using accepted clinical signs. The groups were compared statistically. 45
350
353
OBSERVATIONOF PRE-CORNEA1TEAR FILM USING AN ANTERIOR EYE SECMRNTANALYSIS SYSTEM Kazuyuki Sasaki. Kazuko Kitagawa.Yasuo Sakamoto Department of Ophthalmology. Kanazawa Medical University, Uchinada. JAPAN
UL.TFIASTRUCTUti'CIL STUDY ON HUllAN CORNEA TRATED WITH f:‘HClTOTEf?fWEUTIC k ERATECTOMY A LOFFREDO E VEIX’HIONE M DEL.UTA E LLOFFKEDC -I--------I-L--11----1-:------1-1-------.M. LOFFREDD k,. I- ,, , . Depar-tmwt ef Ophthalmolo~~y !Jnlvri-<
Pre-cornea1 tear film was observed utilizing an image analysis technique. For this purose an anterior eye sequent analysis system (NIDEK EAS-MID). which was developed by the authors’ eroup. was applied. After instillation of 1 ~1 of 2!4 fluorescein sodium into the cul-de-sac. the anterior eye segment was doctuuented with EAS-1000 through exciting and barrier filters which are the same as those used in fluorescein fundus angiography. Documentation was performed every three minutes until the 15th minute. The intensity of fluorescence (1.F.). which was measured by densitometry was applied as an indicator of tear fluid clearance. The I.F. of normal volunteers was compared with those of patients with dry eyes and contact lens wearers. In normal cases. pre-cornea1 fluorescence was measurable up to 6th~-9th rsinute. The methnd applied in this clinical study will be useful for evaluation of tear fluid clearance. A correlation between tha data obtained from this method and those of conventional methods will also be presented.
s.105
Naples E30lBl