Clinical Assessment of the Macula by Retinal Topography and Thickness Mapping

Gieser, Jon P.; Rusin, Mark M.; Mori, Marek; Blair, Norman P.; Shahidi, Mahnaz

doi:10.1016/s0002-9394(14)70903-1

Cited by 31 publications

(15 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…4,10,11 To summarize briefly, a laser slit beam measuring 2 mm × 15 μm (λ = 543 nm) was projected on the retina. Ten slit images were acquired in each of nine 2 mm × 2 mm regions.…”

Section: Methodsmentioning

confidence: 99%

“…3 We have described how this method can be extended to map the retinal thickness in a 6 mm × 6 mm area of the macula with a depth resolution of 50 μm. 4 Although optical coherence tomography can measure retinal thickness with a depth resolution of 10 μm, 5 currently available algorithms allow measurements only in six radial lines passing through the fovea or in a circle concentric with the fovea. Thus, the thickness in large areas of central macula is not directly measured, but interpolated.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Correlation Between Microaneurysms and Retinal Thickness in Diabetic Macular Edema

Blair

Shahidi

Lai

et al. 2008

Retina

Self Cite

View full text Add to dashboard Cite

Background or Purpose Microaneurysms commonly are believed to be related causally to retinal thickening in diabetic retinopathy, especially by leaking. We tested the hypothesis that thicker areas of retina in diabetic retinopathy have more microaneurysms per unit area than areas that are not as thick. Methods Retinal thickness analysis was performed with a prototype instrument in 27 eyes of 27 diabetic patients and in 22 normal eyes of 22 healthy subjects. Maps of retinal thickness were created, and microaneurysms were counted in zones having four levels of retinal thickness. Results There was no increase in either total microaneurysms or apparent leaking microaneurysms per unit area with increasing levels of retinal thickness (P=0.77 and 0.87, respectively). Conclusion Some microaneurysms may not cause thickening, or other factors may contribute to retinal thickening in diabetic retinopathy. The results may have implications on the pathogenesis of diabetic macular edema.

show abstract

“…4,10,11 To summarize briefly, a laser slit beam measuring 2 mm × 15 μm (λ = 543 nm) was projected on the retina. Ten slit images were acquired in each of nine 2 mm × 2 mm regions.…”

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Correlation Between Microaneurysms and Retinal Thickness in Diabetic Macular Edema

Blair

Shahidi

Lai

et al. 2008

Retina

Self Cite

View full text Add to dashboard Cite

show abstract

“…22 The system generates an optical section image of the retina by projecting a laser onto the retina at an angle and viewing the reflection and/or scattering of the laser light from the vitreoretinal and chorioretinal interfaces. The vitreoretinal and chorioretinal interfaces correspond to layers close to the inner limiting membrane and retinal pigment epithelium, respectively.…”

Section: Methodsmentioning

confidence: 99%

“…The digitised images were analysed to determine retinal elevations and thickness by a dedicated software algorithm, as described in detail previously. 22 Two two dimensional arrays containing the topographic data for the vitreoretinal and chorioretinal surfaces were created. Since retinal thickness is defined as the depth separation between the vitreoretinal and chorioretinal interfaces, a two dimensional array containing retinal thickness values was produced by subtracting the two corresponding arrays.…”

Section: Methodsmentioning

confidence: 99%

Retinal topography and thickness mapping in atrophic age related macular degeneration

Shahidi

2002

British Journal of Ophthalmology

View full text Add to dashboard Cite

Aim: To determine the relation between alterations in the retinal topography and thickness, visual acuity, and retinal pigment epithelium hypopigmentation in atrophic age related macular degeneration (AMD). Methods: 22 patients, mean age 74 (SD 8) years, with atrophic AMD were recruited. An optical imaging system based on the retinal thickness analyser (RTA) was applied to generate a series of 20 optical section images that encompass 2 mm × 2 mm retinal areas. The optical section images were digitised and analysed to provide topographic maps of the vitreoretinal and chorioretinal surfaces and the retinal thickness. Vitreoretinal and chorioretinal surface elevations and retinal thickness were determined. Results: Variation in the vitreoretinal surface height was moderately correlated with visual acuity (r = −0.4; p = 0.03; n = 22). Increase in variation of chorioretinal surface height was correlated with decrease in visual acuity (r = −0.5; p = 0.01; n = 22). The retinal thickness was not associated with visual acuity (r = 0.2; p = 0.2; n=22). Relative height of the vitreoretinal surface in eyes with retinal pigment epithelium (RPE) hypopigmentation was significantly less than eyes without RPE hypopigmentation (p = 0.005). Eyes with and without RPE hypopigmentation had a similar relative height of the chorioretinal surface (p = 0.4). Retinal thickness in eyes with RPE hypopigmentation was less than in eyes without RPE hypopigmentation (p = 0.04). Conclusion: Mapping of chorioretinal and vitreoretinal topography and retinal thickness provides objective and quantitative measurements of retinal structural abnormalities and shows promise as an adjunct for the evaluation of retinal structural changes due to AMD.A ge related macular degeneration (AMD) is the most common cause of vision loss in people over 50 years of age.1-5 In non-exudative AMD, loss of vision is caused by atrophy of the retinal pigment epithelium (RPE), outer retina, and choriocapillaris. In the exudative type of AMD, ingrowth of new vessels from the choroid into the subretina and/or sub-RPE space results in vision loss.The survival of the photoreceptors cells is critically dependent on the normal function of the RPE cells. The accumulation of extracellular deposits (drusen) between the RPE and the choroid is known to occur in AMD. 6 The location, composition, and structure of drusen associated with ageing and AMD have been studied. 7 8 Moreover, the RPE overlying drusen have altered lipofuscin autofluorescence, suggestive of additional changes in RPE metabolism due to AMD.9 Furthermore, clinicopathological studies have demonstrated thinning of the retina related to atrophy of retinal photoreceptors. 10

show abstract

“…1 Reliable, quantitative, and sensitive methods to determine retinal thickness will lead to more accurate diagnosis and effective management. For example, the retinal thickness analyser (RTA; Talia Technology Ltd, Neve-IIan, Israel) has been extensively evaluated in clinically normal subjects, 2-8 patients with various retinal diseases, [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] and following various interventions. [28][29][30][31] Retinal thickness measurements using the RTA have been shown to correlate with other techniques 7 27 32 and histological assessment.…”

mentioning

confidence: 99%

Eccentricity and measurement variability and repeatability with the retinal thickness analyser

Gilmore

Hudson²

2004

British Journal of Ophthalmology

View full text Add to dashboard Cite

Aims: To define the variability and repeatability of retinal thickness measurements using the retinal thickness analyser (RTA) and to elucidate any interaction between eccentricity (that is, position relative to the fovea) and variability and repeatability. Methods: The sample comprised 20 normal subjects of mean age 33 years. Each subject attended for two visits. Repeated RTA scans were acquired centred on the fovea and for any one of the four possible non-foveal scan areas. The mean retinal thickness (+SD) was calculated for a series of concentric circular bands centred on fixation. A repeated measures analysis of variance (ANOVA) was used to determine any significant interaction between the variability of RTA thickness values and eccentricity. Results: The group mean coefficient of variation and coefficient of repeatability were highest at the fovea. The repeated measures ANOVA revealed that the within test variability of RTA measurements varied significantly with eccentricity (p,0.0001). Similarly, the between test repeatability varied significantly with eccentricity (p = 0.045). Conclusion:The significantly elevated within test variability and between test repeatability in the foveal area need to be considered when using the RTA to evaluate patients with macular disease.

show abstract

Clinical Assessment of the Macula by Retinal Topography and Thickness Mapping

Cited by 31 publications

References 13 publications

Correlation Between Microaneurysms and Retinal Thickness in Diabetic Macular Edema

Correlation Between Microaneurysms and Retinal Thickness in Diabetic Macular Edema

Retinal topography and thickness mapping in atrophic age related macular degeneration

Eccentricity and measurement variability and repeatability with the retinal thickness analyser

Contact Info

Product

Resources

About