Dr Jennifer Acton
Research Topics and Related Projects:
My research interests involve the examination of structure to function relationships in age-related macular degeneration (AMD), which was established during my PhD and developed during my postdoctoral research fellowships abroad.
Ongoing work includes microperimetry investigations in healthy individuals and in retinal disease. Current projects involve the examination of the normative data, using the Macular Integrity Assessment microperimeter (Figure 1) and evaluation of the relationship of this clinical technique with vision-related quality of life instruments in individuals with AMD.
Figure 1. Figure 1. Microperimetry results in a healthy eye.
Summary of findings:
- In early AMD, thinning of the outer segment layer, measured using retinal layer segmentation of spectral-domain optical coherence tomography images, was significantly associated with reduced microperimetry sensitivity (Figure 1).
- A greater decline in visual loss due to increasing severity of AMD was found, using short-wavelength automated perimetry compared to conventional perimetry, although not all individuals with AMD are suitable for SWAP examinations.
- A Bayesian model was appropriate to model normative data collected using the MP-1 microperimeter.
- Despite similarities in stimuli and threshold procedures between microperimetry (MP-1) and conventional perimetry (HFA), there are important differences between instruments that need to be taken into account when interpreting visual field results. These include the difference in dynamic range, normative data and background luminance levels. The amount of visual loss detected, differed between instruments and this was dependent upon adaptation level and type of retinal disease.
Figure 2. Microperimetry results in early AMD.
Acton JH (PI) & Margrain TH, £15,000, Evaluation of the Macular Integrity Assessment microperimeter, Fight for Sight, 2013
Prof Victor Chong, Oxford Eye Hospital, Clinical Evaluation of Macular Disease
Dr Vivienne C. Greenstein, Dept of Ophthalmology, Columbia University, Microperimetry in retinal disease