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Morgan WH, Hazelton ML, Balaratnasingamm C, Chan H, House PH, Barry CJ, Cringle SJ, Yu DY. The association between retinal vein ophthalmodynamometric force change and optic disc excavation. Br J Ophthalmol 2008; 93:594-6. [PMID: 19098037 DOI: 10.1136/bjo.2008.149963] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM Retinal vein ophthalmodynamometric force (ODF) is predictive of future optic disc excavation in glaucoma, but it is not known if variation in ODF affects prognosis. We aimed to assess whether a change in ODF provides additional prognostic information. METHODS 135 eyes of 75 patients with glaucoma or being glaucoma suspects had intraocular pressure (IOP), visual fields, stereo optic disc photography and ODF measured on an initial visit and a subsequent visit at mean 82 (SD 7.3) months later. Corneal thickness and blood pressure were recorded on the latter visit. When venous pulsation was spontaneous, the ODF was recorded as 0 g. Change in ODF was calculated. Flicker stereochronoscopy was used to determine the occurrence of optic disc excavation, which was modelled against the measured variables using multiple mixed effects logistic regression. RESULTS Change in ODF (p = 0.046) was associated with increased excavation. Average IOP (p = 0.66) and other variables were not associated. Odds ratio for increased optic disc excavation of 1.045 per gram ODF change (95% CI 1.001 to 1.090) was calculated. CONCLUSION Change in retinal vein ODF may provide additional information to assist with glaucoma prognostication and implies a significant relationship between venous change and glaucoma patho-physiology.
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Affiliation(s)
- W H Morgan
- Department of Physiology and Pharmacology, Lions Eye Institute, Nedlands, Western Australia, Australia.
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2
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Lai CM, Dunlop SA, May LA, Gorbatov M, Brankov M, Shen WY, Binz N, Lai YK, Graham CE, Barry CJ, Constable IJ, Beazley LD, Rakoczy EP. Generation of transgenic mice with mild and severe retinal neovascularisation. Br J Ophthalmol 2005; 89:911-6. [PMID: 15965177 PMCID: PMC1772733 DOI: 10.1136/bjo.2004.059089] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM To generate a mouse model for slow progressive retinal neovascularisation through vascular endothelial growth factor (VEGF) upregulation. METHODS Transgenic mice were generated via microinjection of a DNA construct containing the human VEGF165 (hVEGF) gene driven by a truncated mouse rhodopsin promoter. Mouse eyes were characterised clinically and histologically and ocular hVEGF levels assayed by ELISA. RESULTS One transgenic line expressing low hVEGF levels showed mild clinical changes such as focal fluorescein leakage, microaneurysms, venous tortuosity, capillary non-perfusion and minor neovascularisation, which remained stable up to 3 months postnatal. Histologically, there were some disturbance and thinning of inner and outer nuclear layers, with occasional focal areas of neovascularisation. By contrast, three other lines expressing high hVEGF levels presented with concomitantly severe phenotypes. In addition to the above, clinical features included extensive neovascularisation, haemorrhage, and retinal detachment; histologically, focal to extensive areas of neovascularisation associated with retinal folds, cell loss in the inner and outer nuclear layers, and partial retinal detachment were common. CONCLUSIONS The authors generated four hVEGF overexpressing transgenic mouse lines with phenotypes ranging from mild to severe neovascularisation. These models are a valuable research tool to study excess VEGF related molecular and cellular changes and provide additional opportunities to test anti-angiogenic therapies.
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Affiliation(s)
- C-M Lai
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Nedlands, Australia.
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3
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Spinner RJ, Wenger DE, Barry CJ, Goldner RD. Episodic snapping of the medial head of the triceps due to weightlifting. J South Orthop Assoc 2002; 8:288-92. [PMID: 12132803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
We describe two patients who had episodic elbow snapping and ulnar nerve dysesthesias only after weightlifting. These symptoms would disappear soon afterward. The episodic nature of their complaints and findings led to misdiagnosis. We documented by repeated clinical examinations and magnetic resonance imaging that the presence of these symptoms correlated directly with the finding of intermittent, activity-related snapping of the medial triceps. In both patients, the symptoms disappeared when the medial portion of the triceps migrated medially but did not dislocate over the medial epicondyle with elbow flexion. Thus, a minor change in the configuration of the medial portion of the triceps (fluid accumulation) in the same individual at different times can cause intermittent dislocation of the medial triceps. Previous papers dealing with patients with snapping of the medial triceps describe symptoms exacerbated by athletic activities, but the constant finding of snapping on sequential examinations.
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Affiliation(s)
- R J Spinner
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minn, USA
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4
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Abstract
In prisons, prison medical officers provide general medical care. However, if specialist care is needed then the prisoner is transported to a specialist medical centre. This is a costly procedure and prison escapes occur during transportation. We have tested our Internet-based eye care system in prisons in Western Australia. Medical and ophthalmic history, visual acuity and intraocular pressure were stored in a browser-based multimedia database. Digital images of the retina and the external eye were recorded and transmitted to a central server. Based on the medical data and the digital images, the specialist ophthalmologist could provide a diagnosis within 24 h. Eleven patients (mean age 48, range 30-82 years) were reviewed during two separate visits to a maximum-security prison in Western Australia. Our main aim was to train prison medical officers and nurses to operate the portable ophthalmic imaging instruments and to use the Internet-based eye care system. The outcome of the pilot study indicated that considerable savings could be made in transport costs and the security risk could be reduced. The Ministry of Justice in Western Australia has decided to implement telemedicine services to provide regular ophthalmic consultation to its prisons.
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Affiliation(s)
- K Yogesan
- Centre for E-Health, Lions Eye Institute, University of Western Australia, Nedlands, Australia.
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5
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Abstract
The case is presented of metastatic carcinoma to the retina in a 63-year-old woman with known disseminated large bowel carcinoma. The clinical appearance and angiographic features are discussed.
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Affiliation(s)
- B M Hutchison
- Lions Eye Institute, Nedlands, Western Australia, Australia
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6
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Barry CJ, Henderson C, Kanagasingam Y, Constable IJ. Working toward a portable tele-ophthalmic system for use in maximum-security prisons: a pilot study. Telemed J E Health 2001; 7:261-5. [PMID: 11564362 DOI: 10.1089/153056201316970966] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The medical care of prisoners is a difficult and often costly process. Basic medical needs are serviced by prison medical officers. However, specialized care often means transport to specialist centers with the attendant cost and safety. We examined portable ophthalmic equipment in a prison environment to screen 11 prisoners who were scheduled for specialist ophthalmic assessment. Medical and ophthalmic histories were documented, visual acuity was tested, digital images were taken of the external eye and retina, and intraocular pressures taken. The data were sent via modem to a specialist ophthalmologist, and the reports were dictated via e-mail at the end of each session. Of the 11 patients who were scheduled to travel for ophthalmic assessment, only 2 were still required to travel to a specialist ophthalmic center. This pilot study showed that there were considerable cost savings to be made by this screening process with the attendant increase in community safety. The prototype equipment requires refinement by further experimentation, but showed the potential as an adjunct to current examination and assessment techniques when applied to a prison population.
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Affiliation(s)
- C J Barry
- Lions Eye Institute, Center for Ophthalmology and Visual Science, University of Western Australia, 2 Verdun Street, Perth 6009, Western Australia.
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7
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Barry CJ, Morgan WH, Jitskaia L, Eikelboom RH, Kanagasingam Y. Computer-assisted planimetry associated with Sturge-Weber syndrome. J Audiov Media Med 2000; 23:149-52. [PMID: 11271862 DOI: 10.1080/01405110050198591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Photographs of the optic nerve head (optic disc) in the eye are used for the clinical assessment of the disease glaucoma. These images are usually subjectively assessed by a clinician. A case of Sturge-Weber Syndrome which includes glaucoma as a symptom, is presented here. Narrowing of the rim of the optic disc was measured using custom-made measurement software confirming glaucomatous progression. To maximize the information obtained from optic disc images, low cost software can assist with quantifying disc parameters aiding clinical interpretation.
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Affiliation(s)
- C J Barry
- Centre for Ophthalmology and Visual Science, University of Western Australia, Lions Eye Institute, 2 Verdun St., Nedlands 6009, Western Australia.
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Yogesan K, Constable IJ, Barry CJ, Eikelboom RH, McAllister IL, Tay-Kearney ML. Telemedicine screening of diabetic retinopathy using a hand-held fundus camera. Telemed J 2000; 6:219-23. [PMID: 10957734 DOI: 10.1089/107830200415153] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The objective was to evaluate digital images of the retina from a handheld fundus camera (Nidek NM-100) for suitability in telemedicine screening of diabetic retinopathy. A handheld fundus camera (Nidek) and a standard fundus camera (Zeiss) were used to photograph 49 eyes from 25 consecutive patients attending our diabetic clinic. One patient had cataracts, making it impossible to get a quality image of one of the eyes (retina). The Nidek images were digitized, compressed, and stored in a Fujix DF-10M digitizer supplied with the camera. The digital images and the photographs were presented separately in a random order to three ophthalmologists. The quality of the images was ranked as good, acceptable or unacceptable for diabetic retinopathy diagnosis. The images were also evaluated for the presence of microaneurysms, blot hemorrhages, exudates, fibrous tissue, previous photocoagulation, and new vessel formation. kappa Values were computed for agreement between the photographs and digital images. Overall agreement between the photographs and digital images was poor (kappa < 0.30). On average, only 24% of the digital images were graded as being good quality and 56% as having an acceptable quality. However, 93% of the photographs were graded as good-quality images for diagnosis. The results indicate that the digital images from the handheld fundus camera may not be suitable for diagnosis of diabetic retinopathy. The images shown on the liquid crystal display (LCD) screen of the camera were of good quality. However, the images produced by the digitizer (Fujix DF-10M) attached to the camera were not as good as the images shown on the LCD screen. A better digitizing system may produce better quality images from the Nidek camera.
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Affiliation(s)
- K Yogesan
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, The University of Western Australia, Nedlands, Australia.
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9
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Abstract
A digital indirect ophthalmoscope (DIO) was developed and tested for use in tele-ophthalmology screening for posterior and anterior segment diseases. Using custom software, images from the DIO were digitized, compressed, stored and transmitted to a centralized eye clinic for interpretation. A total of 43 subjects were primarily screened for glaucoma using the DIO, a hand-held fundus camera and a stereo fundus camera. The photographic slides from the stereo fundus camera used as gold standards. Images (390 x 300 pixels x 3 bits) were stored using a laptop computer together with patient information. Image quality received at the central eye clinic was good and showed adequate diagnostic information. An ophthalmologist estimated cup-disc ratios and graded the quality of the images. The sensitivity and specificity of each instrument was calculated. A high sensitivity and specificity was found when using the DIO, indicating that it could be used in tele-ophthalmic screenings. Further modifications are needed to make the instrument more user-friendly and to enable it to be used with undilated pupils, so that it can be easily operated by health-care personnel in remote areas. The camera can also be used to image gross external eye pathology.
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Affiliation(s)
- K Yogesan
- Centre for Ophthalmology and Visual Science, Lions Eye Institute, University of Western Australia, Australia.
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10
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Abstract
The neuroretinal rims of a set of glaucoma patients were measured using digitized stereo photographs, to determine the reproducibility of computerized stereo measurements of the neuroretinal rim. Each rim was measured five times at 18 locations, with measurement error (ME) defined as the mean of standard deviations of each set of measurements. The following ME were determined: (i) inter-sessional variability (n = 27 right and 24 left eyes, at t1 and t2); (ii) inter-assessor variability (n = 9, 2 assessors); and (iii) variability after colour adjustment algorithms were applied (n = 15). The results were as follows: (i) inter-sessional variability was 3.41+/-1.08 for t1 and 3.22+/-0.84 for t2; (ii) there was a significant difference between the two assessors, although the ME was still low; and (iii) there was no significant differences between the ME of unadjusted and adjusted images. With a measurement error of up to 11% of rim width, these results show that lowcost rim measurements can be made using PC-based software.
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Affiliation(s)
- R H Eikelboom
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, University of Western Australia, Nedlands, Australia.
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Eikelboom RH, Yogesan K, Barry CJ, Constable IJ, Tay-Kearney ML, Jitskaia L, House PH. Methods and limits of digital image compression of retinal images for telemedicine. Invest Ophthalmol Vis Sci 2000; 41:1916-24. [PMID: 10845617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
PURPOSE To investigate image compression of digital retinal images and the effect of various levels of compression on the quality of the images. METHODS JPEG (Joint Photographic Experts Group) and Wavelet image compression techniques were applied in five different levels to 11 eyes with subtle retinal abnormalities and to 4 normal eyes. Image quality was assessed by four different methods: calculation of the root mean square (RMS) error between the original and compressed image, determining the level of arteriole branching, identification of retinal abnormalities by experienced observers, and a subjective assessment of overall image quality. To verify the techniques used and findings, a second set of retinal images was assessed by calculation of RMS error and overall image quality. RESULTS Plots and tabulations of the data as a function of the final image size showed that when the original image size of 1.5 MB was reduced to 29 KB using JPEG compression, there was no serious degradation in quality. The smallest Wavelet compressed images in this study (15 KB) were generally still of acceptable quality. CONCLUSIONS For situations where digital image transmission time and costs should be minimized, Wavelet image compression to 15 KB is recommended, although there is a slight cost of computational time. Where computational time should be minimized, and to remain compatible with other imaging systems, the use of JPEG compression to 29 KB is an excellent alternative.
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Affiliation(s)
- R H Eikelboom
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, The University of Western Australia, Nedlands.
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12
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Barry CJ, Eikelboom R, Kanagasingam Y, Jitskaia L, Morgan W, House P, Cuypers M. Comparison of optic disc image assessment methods when examining serial photographs for glaucomatous progression. Br J Ophthalmol 2000; 84:28-30. [PMID: 10611095 PMCID: PMC1723220 DOI: 10.1136/bjo.84.1.28] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM To assess serial, simultaneous stereo optic disc images by four methods for glaucomatous progression. METHODS Using varying techniques, two ophthalmologists assessed serial optic disc images of 52 eyes from 27 patients with a mean duration between images of 18 months. The neuroretinal rim width was qualitatively assessed by four assessment methods and compared with quantitative rim measurements made using PC based software. RESULTS The highest sensitivity of 83% was achieved using computerised stereo chronoscopy. CONCLUSION Stereo chronoscopy improved the detection of subtle optic disc changes when compared with simpler assessment techniques.
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Affiliation(s)
- C J Barry
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Lions Eye Institute, Nedlands, Perth, Western Australia
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13
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Yogesan K, Constable IJ, Barry CJ, Eikelboom RH, Morgan W, Tay-Kearney ML, Jitskaia L. Evaluation of a portable fundus camera for use in the teleophthalmologic diagnosis of glaucoma. J Glaucoma 1999; 8:297-301. [PMID: 10529928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
PURPOSE The digital images of the optic disk from a portable fundus camera were evaluated for suitability in teleophthalmologic screening for glaucoma. METHODS Fifty-one eyes of 27 consecutive patients from our glaucoma clinic were dilated and photographed with a Zeiss FF retinal camera (Carl Zeiss, Oberkochen, Germany) and a portable Nidek NM-100 (Nidek, Tokyo, Japan) fundus camera. Digital images from the portable fundus camera were digitized, compressed and stored in a Fujix DF-10M (Fuji, Tokyo, Japan) digitizer. Lossy compressed digital images and photographs from the Zeiss camera were presented separately in random order to three ophthalmologists for estimation of vertical cup:disk ratios (VCDR) and to evaluate image quality as good, acceptable, or unacceptable for screening glaucoma. Gold standard VCDRs were measured from monoscopic photographic slides obtained using the Zeiss camera by a fourth ophthalmologist. RESULTS Measurement of agreement (Kappa values) between estimated VCDR of digital images and photographs by the three ophthalmologists were 0.52, 0.38, and 0.50 respectively. Agreement between gold standard and estimated VCDR from photographs were 0.87, 0.45, and 0.84 respectively (specificity between 79% and 97%, sensitivity between 70% and 95%). Kappa values obtained between gold standard and estimated VCDR from digital images were 0.52, 0.49, and 0.49, respectively (specificity between 68% and 79%, sensitivity between 67% and 87%. CONCLUSION Moderate to good agreement indicates that the digital images from the portable fundus camera may be suitable for optic disk assessment in the current configuration. This easy to use Nidek hand-held camera could be a viable instrument for teleophthalmology if a better digitizing system is incorporated to improve the quality of the images.
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Affiliation(s)
- K Yogesan
- Lions Eye Institute Centre for Ophthalmology and Visual Science, University of Western Australia, Nedlands, Australia
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14
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Rosen BS, Barry CJ, Nicoll AM, Constable IJ. Conservative management of documented neuroretinitis in cat scratch disease associated with Bartonella henselae infection. Aust N Z J Ophthalmol 1999; 27:153-6. [PMID: 10379716 DOI: 10.1046/j.1440-1606.1999.00174.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Bartonella henselae has been identified as the causative agent of the neuroretinitis associated with cat scratch disease (CSD). Immunofluorescent antibody tests with good sensitivity and specificity are available to aid in diagnosis. Despite diagnostic advances, optimal management remains controversial. We present a case of documented B. henselae macular neuroretinitis managed without antibiotics and discuss antibiotic use in this condition. METHODS We examined a young woman with macular neuroretinitis and established a diagnosis of CSD. Management consisted of a review of the literature, followed by educating her about the condition and close observation. We documented the course of her disease. RESULTS We diagnosed neuroretinitis associated with B. henselae infection based on immunofluorescent antibody titres and clinical presentation. Our patient's neuroretinitis resolved promptly without antibiotic therapy. CONCLUSIONS Macular neuroretinitis in CSD can be satisfactorily diagnosed with the use of fluorescent antibodies in the appropriate clinical setting. Optimal treatment for the disease has not been established and observation combined with patient education remains an appropriate option. The self-limited nature of the disease implies that treatment studies not using controls must be interpreted with great caution. Adverse drug reactions and other iatrogenic complications can be reduced by limiting antibiotic use in settings where a meaningful treatment benefit has not been established.
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Affiliation(s)
- B S Rosen
- Centre for Ophthalmology and Visual Science, Lions Eye Institute, Nedlands, Western Australia, Australia.
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Rolling F, Shen WY, Tabarias H, Constable I, Kanagasingam Y, Barry CJ, Rakoczy PE. Evaluation of adeno-associated virus-mediated gene transfer into the rat retina by clinical fluorescence photography. Hum Gene Ther 1999; 10:641-8. [PMID: 10094207 DOI: 10.1089/10430349950018715] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The purpose of this study was to evaluate recombinant adeno-associated virus (AAV) as an in vivo gene transfer vector for the retina and to explore the possibility of monitoring the expression of green fluorescent protein (GFP) using a noninvasive method. Rats were injected subretinally with rAAV-gfp or rAAV-lacZ. Strong expression of the reporter gene in a circular area surrounding the injection site was observed in retinal whole mounts and tissue sections. Higher magnification revealed that cells demonstrating high levels of green fluorescence were hexagonal in shape, indicating they were retinal pigment epithelium (RPE) cells. Histological observation of retinal sections demonstrated that recombinant AAV specifically transduced RPE cells. Ten animals were injected with rAAV-gfp for longitudinal studies and the fluorescence was monitored by retinal fluorescence photography. The GFP signal was detected in 100% of the animals as early as 2 weeks postinjection and remained present throughout the experimental period of 4 months. After 2 weeks, a gradual increase in the number of transduced cells occurred before reaching maximal levels of GFP expression at 8 weeks. This was followed by a small decrease over 4 weeks before reaching stable expression at 16 weeks. Our results demonstrated that rAAV efficiently transduces rat RPE cells and that retinal fluorescence photography is suitable for monitoring GFP expression. By using this noninvasive technique, we demonstrated that repetitive measurements of GFP expression in vivo in the rAAV-gfp-transduced retina are possible. This study demonstrated that retinal fluorescence photography is a potent tool for studying AAV-mediated gene delivery in the retina.
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Affiliation(s)
- F Rolling
- Lions Eye Institute, Perth, Western Australia, Australia.
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Abstract
Two ophthalmic case histories requiring differing techniques to document the long-term outcomes of ocular tumours are presented. In the first case, after documenting a treated choroidal melanoma it was necessary to intervene with digital manipulation to enhance the images for clinical interpretation. Conversely, after documenting an iris tumour over an eight-year period, it was considered that the original images were suitable for interpretation without intervention. This raises the issue of images presented as legal evidence when digital technology is used to manipulate and enhance the images. Are these images admissible as evidence in court, and should the original data also be archived to prevent conflicting interpretations by the legal system? In light of The House of Lords recommendations on digital images as evidence, it is suggested that both the manipulated and original images are archived to avoid debate on the extent to which an image has been altered.
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Affiliation(s)
- C J Barry
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, Perth, Western Australia.
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17
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Barry CJ, Kanagasingam Y, Morgan W. Optic disc topographic changes post-trabeculectomy visualized by anaglyphs. Aust N Z J Ophthalmol 1999; 27:79-83. [PMID: 10080344 DOI: 10.1046/j.1440-1606.1999.00149.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Publications on changes of optic disc topography usually illustrate their findings with two-dimensional images. METHODS With the introduction of computerized imaging, anaglyphs of stereo images can be produced for illustrations. Anaglyphs are viewed three-dimensionally with red-green spectacles that are included in refraction sets and are normally used to assess phoria. An anaglyph of progressive, glaucomatous progression is included to demonstrate the method, along with conventional colour images. RESULTS We present two cases of severely altered optic disc topography post-trabeculectomy and illustrate these cases with anaglyphs that can be viewed three-dimensionally. CONCLUSION Three-dimensional viewing of illustrations assists with the visualization, perception and interpretation of optic disc changes.
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Affiliation(s)
- C J Barry
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, Perth, Western Australia, Australia.
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18
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Yogesan K, Barry CJ, Jitskaia L, Eikelboom RH, Morgan WH, House PH, van Saarloos PP. Software for 3-D visualization/analysis of optic-disc images. IEEE Eng Med Biol Mag 1999; 18:43-9. [PMID: 9934599 DOI: 10.1109/51.740963] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- K Yogesan
- Centre for Ophthalmology and Visual Science, Lions Eye Institute, University of Western Australia.
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19
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Shen WY, Yu MJ, Barry CJ, Constable IJ, Rakoczy PE. Expression of cell adhesion molecules and vascular endothelial growth factor in experimental choroidal neovascularisation in the rat. Br J Ophthalmol 1998; 82:1063-71. [PMID: 9893599 PMCID: PMC1722761 DOI: 10.1136/bjo.82.9.1063] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To investigate the longevity and reproducibility of choroidal neovascularisation (CNV) induced by krypton laser photocoagulation in the rat. The presence of cell adhesion molecules (CAMs) and vascular endothelial growth factor (VEGF) during the development of CNV was also studied. METHODS 67 pigmented rats underwent retinal photocoagulation by krypton laser. The eyes were examined by either single or serial fluorescein angiography at 3 days, 1, 2-3, 4-5, 7-8, and 12 weeks post photocoagulation. The expression of CAMs (ICAM-1, E-selectin, and CD44) and VEGF post photocoagulation was studied by immunohistochemistry. RESULTS CNV related fluorescein leakage appeared in 46.4% of 766 laser spots delivered to the 58 eyes that were tested at 2-3 weeks post treatment. The ratio of hyperfluorescent laser sites did not change significantly at 8 weeks post laser. The number of leaky spots was independent of the total number of lesions delivered to each eye (at 2-3 weeks post laser 10-15 spots/eye: 44% and 25-30 spots/eye: 49%; t = 0.7673; p = 0.3903). Nine eyes were followed by serial angiography between 2 and 12 weeks. The laser spots with fluorescein leakage at 2 weeks (51.5%) remained leaky at 12 weeks (51.5%). Histopathologically, macrophage accumulation peaked at 5 days and CNV was firstly observed at 1 week post photocoagulation. ICAM-1, E-selectin, CD44, and VEGF were maximally induced at 3-5 days post laser photocoagulation, and were localised to RPE, choroidal vascular endothelial, and inflammatory cells. VEGF was also detected in intravascular leucocytes at the sites of laser lesions. CONCLUSIONS These studies demonstrated that krypton laser photocoagulation can be successfully used to produce lesions similar to those of human CNV. The response induced remained present for an extended period of time (12 weeks), thus offering a potential model to screen candidate CNV inhibitory agents. In addition, it is proposed that the expression of ICAM-1, E-selectin, CD44, and VEGF before new vessel formation might be linked to the initiation of CNV.
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Affiliation(s)
- W Y Shen
- Centre for Ophthalmology and Visual Sciences, University of Western Australia, Lions Eye Institute, Perth, Western Australia
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Barry CJ, Yogesan K, Jitskaia L, Morgan WH, House PH, Eikelboom RH. A personal computer-based method of stereo chronometry for measuring neuroretinal rim width: a pilot study. Aust N Z J Ophthalmol 1998; 26 Suppl 1:S22-5. [PMID: 9685014 DOI: 10.1111/j.1442-9071.1998.tb01363.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Quantifying neuroretinal rim width from optic disc photographs to study glaucomatous progression requires precise, reproducible measurements. We explored the use of a personal computer with three-dimensional capabilities to enhance measurement accuracy and repeatability. METHODS A simultaneous stereo retinal camera was used to serially photograph the optic discs often glaucomatous eyes with a mean interval of 18 months. The neuroretinal rims were qualitatively assessed as either stable (five) or narrowing (five). The images were measured using software written for an IBM compatible personal computer The measurements were compared from the earliest to the most recent image and the five narrowed rims were correctly identified. RESULTS This simple, low-cost method allowed both three-dimensional viewing and measurement of the optic disc rim from simultaneous stereo images. CONCLUSIONS This method is, potentially, more sensitive in identifying glaucomatous rim changes than conventional, subjective image comparison techniques.
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Affiliation(s)
- C J Barry
- Centre for Ophthalmology and Visual Science, Lions Eye Institute, Perth, Western Australia, Australia.
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Kumar B, Yu DY, Morgan WH, Barry CJ, Constable IJ, McAllister IL. The distribution of angioarchitectural changes within the vicinity of the arteriovenous crossing in branch retinal vein occlusion. Ophthalmology 1998; 105:424-7. [PMID: 9499771 DOI: 10.1016/s0161-6420(98)93022-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE Branch retinal vein occlusions (BRVOs) are known to occur most commonly in the vicinity of arteriovenous (A/V) crossings. The authors aimed to identify types of venous wall abnormalities in BRVO and document their position in relation to the A/V crossing. DESIGN A retrospective review of the color photographs and fluorescein angiograms from the most recent 110 patients with first- or second-order BRVO was performed. MAIN OUTCOME MEASURES The films were examined for the presence of angioarchitectural changes of specified type within one-quarter disk diameter of the A/V crossing involved in the BRVO. The specific changes noted were fluorescein leakage, presumed thrombi, and flow abnormalities, which were recorded along with their position in relation to the A/V crossing. RESULTS Of the 110 patients diagnosed with BRVO, 59 had photography of satisfactory quality. Forty-one (70%) of these 59 patients had venous lesions, of which significantly more (chi-square -5.74, P < 0.02) were downstream (56%) than upstream (12%) from the A/V crossing. Thirty-two percent were upstream and downstream. Of the hemodynamic changes seen, 49% had late venous phase leakage of fluorescein, 85% had abnormal flow, and 7% had presumed thrombi. All thrombi seen were downstream. CONCLUSIONS Venous lesions in the vicinity of the A/V crossing commonly are seen in BRVO, most of which occur downstream. This suggests that the venous narrowing at the crossing may induce downstream hemodynamic changes predisposing to endothelial damage and thrombus generation.
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Affiliation(s)
- B Kumar
- Lions Eye Institute, University of Western Australia, Perth, Western Australia
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Abstract
PURPOSE To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. METHODS The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4-6 months and glaucoma suspects every 1-2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. RESULTS It was found that during the period under review, 7.4% (n = 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P = 0.0001) followed by 11% of primary open-angle glaucoma eyes (P = 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. CONCLUSIONS A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance.
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Affiliation(s)
- C J Barry
- Centre for Ophthalmology and Visual Science, Lions Eye Institute, Perth, Australia
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Affiliation(s)
- L da Cruz
- Lions Eye Institute, Perth, Western Australia
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Abstract
OBJECTIVE To compare the Zeiss retinal camera with the Nidek 3-Dx camera for photographic quality and stereo separation. SUBJECTS Eleven subjects (22 eyes) were selected from patients referred for optic disc photography. METHODS The subjects were photographed using the Nidek 3-Dx camera for simultaneous stereo photographs, and the 30 degrees field and 15 degrees field settings on the Zeiss retinal camera for sequential stereo photographs. Four ophthalmologists qualitatively scored the photographs on a five-point scale for stereo separation and photographic resolution and sharpness. The results from the four observers were averaged and the Friedman two-way analysis of variance used to analyse the results. CONCLUSIONS It was found that the stereo separation is significantly better using the Nidek camera when compared with both the 30 degrees and 15 degrees Zeiss results. There was no significant difference in photographic quality between the Nidek and Zeiss 30 degrees photographs. It was also found that the Zeiss 30 degrees images had a significantly higher quality than the Zeiss 15 degrees, which contradicted previous results.
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Affiliation(s)
- C J Barry
- Centre for Ophthalmology and Visual Science, University of Western Australia, Nedlands
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Kennedy CJ, Barry CJ, Constable IJ. Symptoms and signs of retinal disease. Aust Fam Physician 1994; 23:581, 584-5, 588-9 passim. [PMID: 8198478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Of all the diseases of the eye, the retinal disorders are perhaps the most frequently misdiagnosed by the general medical community. The content of this article is restricted to retinal diseases and the importance of symptoms and signs in their accurate diagnosis.
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Abstract
The red-free negatives of 53 right eyes (30 normal eyes and 23 glaucomatous eyes) and 51 left eyes (32 normal eyes and 19 glaucomatous eyes) were analysed using two different image densitometry techniques. The first technique measured the density from rectangular sample areas, while the second measured density from sector-shaped sample areas which more closely follow the course of the nerve fibres in the retina. Indices which measured the deviation of the data from a clinically determined normal 'gold standard' were calculated, and were used to determine the optimum sensitivity and specificity in separating normal from glaucomatous eyes. There is a significant difference between the data from the normal and glaucomatous groups of eyes, when measured from the sector sample areas. The relative efficacy of this technique is also shown by the improved values of sensitivity (from 42%-70% to 70%-91%), although specificity remained fairly constant (from 66%-83% to 62%-88%).
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Barry CJ, Eikelboom RH. Optic disc haemorrhages: comparison of accessory magnifying attachments for the Zeiss retinal camera. Aust N Z J Ophthalmol 1993; 21:201-3. [PMID: 8260162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- C J Barry
- Lions Eye Institute, Nedlands, Western Australia
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Barry CJ. Variable angle retinal nerve fibre layer photography: a review. J Audiov Media Med 1992; 15:148-54. [PMID: 1339786 DOI: 10.3109/17453059209088462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Optic disc and retinal nerve fibre layer (RNFL) photography have been an integral part of the routine screening of glaucoma patients, ocular hypertensives and glaucoma suspects in Perth since 1979. During this period 60 degrees, 40 degrees, 30 degrees and 8 degrees angles of view were examined for potential use in RNFL photography. The degree of dilation and media opacity is highly variable in glaucoma patients because of the age group involved and the miotic therapy. It was found that the 30 degree angle of view gave the most consistent results for routine RNFL photography. Ocular hypertensives tended to be of a lower mean age and 40 degrees wide angle photography was possible but required two different photographic techniques and was not continued. Both 60 degrees and high-magnification RNFL photography are currently used only with selected patients for teaching and demonstration. A modified Hasselblad 120 roll film camera was used for high-resolution RNFL photography. The Hasselblad adaptors, high-resolution results and comparisons with wide-angle RNFL photographs are illustrated in this paper.
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Affiliation(s)
- C J Barry
- Lions Eye Institute, Nedlands, Perth, Western Australia
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Cooper RL, Eikelboom RH, Barry CJ. Correlations between densitometry of red-free photographs and reflectometry with the scanning laser ophthalmoscope in normal subjects and glaucoma patients. Int Ophthalmol 1992; 16:243-6. [PMID: 1428551 DOI: 10.1007/bf00917969] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To compare image measurements of the retina produced by scanning laser ophthalmoscopy with those from red-free photographs (RFP) of the nerve fibre layer. SUBJECTS The left eyes of 23 subjects (10 normal, 7 glaucoma suspect and 6 glaucomatous) were included in this study. METHOD All the eyes were photographed using standard red-free photography, and images of the retina were digitised directly from the SLO. RESULTS The correlation coefficient for all except three subjects was > 0.45, and the probability (p) that R = 0 was < 0.05 in all but 5 eyes. CONCLUSIONS The data indicate that variations in retinal surface reflectivity as measured by the SLO are similar to those recorded on negative film during RFP. This further suggests that the SLO can be useful for making objective measurements of the RNFL, without the intermediate and variable steps of photography.
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Affiliation(s)
- R L Cooper
- Lions Eye Institute, University of Western Australia, Nedlands
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Barry CJ, Cooper RL. Use of unsharp masks with high-contrast retinal nerve fibre layer photographs. J Audiov Media Med 1992; 15:108-11. [PMID: 1460239 DOI: 10.3109/17453059209018362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Retinal nerve fibre layer (RNFL) photography is an established and integral tool in the management of ocular hypertensives and glaucoma suspects, and in assessing the management of glaucoma in an ophthalmic practice. When RNFL negatives are viewed for analysis, high-contrast negatives yield the most information. When positive prints are subsequently requested, the RNFL negatives are difficult to print. The use of an unsharp mask facilitates the transfer of all the high-contrast negative density range to the print. The use of an unsharp mask has been simplified so that it is quick and efficient and can be adapted for high-contrast negatives other than RNFL images.
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Affiliation(s)
- C J Barry
- Lions Eye Institute, Nedlands, Perth, Western Australia
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Abstract
Fundus photography is now an established tool for showing early changes in the retinal nerve fibre layer (RNFL). RNFL defects may precede glaucomatous visual field defects by up to five years and any improvement in photography should aid RNFL defect analysis. We have found that the use of an unsharp mask has helped to visualise the RNFL and by using readily available darkroom materials the process of unsharp mask preparation has been simplified.
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Affiliation(s)
- C J Barry
- Lions Eye Institute, Nedlands, Western Australia
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Eikelboom RH, Cooper RL, Barry CJ. A study of variance in densitometry of retinal nerve fiber layer photographs in normals and glaucoma suspects. Invest Ophthalmol Vis Sci 1990; 31:2373-83. [PMID: 2243002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The main object of this research was to develop a reliable method of screening glaucoma suspects and patients for early loss of or changes in the retinal nerve fiber layer (RNFL). This study quantifies the variances due to photography, digitizing, and analysis of red-free photographs of the RNFL. The influence of pupil size, optic disc position and eye movements, film processing, digitizing, and intra- and interphotographic-session and intra- and interoperator variances were established. It was found that pupils needed to be dilated to at least 6 mm, that the optic disc had to be positioned in a standardized area in the negative, that the head of the subject had to remain still during photography, and that film processing and digitizing of the negative needed to be strictly controlled to minimize the variance in collection of densitometry data from RNFL red-free photographs. It was established that focusing of the negatives during digitization was not crucial. Criteria were defined for acceptable negatives. Interphotographic-session and intraoperator variances were not significant in most cases when negatives were digitized to these criteria. Analysis of interphotographic-session variance showed that there were still some factors in photography, film processing, and/or image digitizing that were not sufficiently controlled for long-term follow-up without normalization of the data. Densitometry data gathered using the established protocol, from negatives of 71 subjects were analyzed; best sensitivity and specificity rates of 80% and 100%, respectively, were achieved for the diagnosis of glaucoma.
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Affiliation(s)
- R H Eikelboom
- Department of Ophthalmology, University of Western Australia, Nedlands
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Pegrum GD, Barry CJ. The effects of adding reticulo-endothelial tissue extracts to human leucocyte cultures. J Pathol Bacteriol 1968; 96:187-201. [PMID: 5243851 DOI: 10.1002/path.1700960120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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