Before surgery, all patients presented predominantly eccentric fixation
. After surgery, 8 of them had poor central fixation and 2 predominantly central fixation (Table 3).
However, pathologies such as ERM which cause eccentric fixation
may result in the measurement of axial length on a different axis and lead to refractive deviations.
Gary Rubin, professor of visual rehabilitation at the Institute of Ophthalmology, opened with an account of the EFFECT (Eccentric Fixation
From Enhanced Clinical Training) study, a randomised control study comparing enhanced vision techniques (EVT) with the conventional hospital low vision service.
Phenomenology of eccentric fixation
. American Journal of Ophthalmology, 53, 642-660.
With the capability to correct for unstable or eccentric fixation
, a measure of sensitivity at any predetermined retinal location can be obtained.
A study by Zeevi, Peli, and Stark (1979) suggested that eccentric fixation
within the near periphery, plus or minus 8 degrees, can be achieved within a short period of time (10-40 seconds), even in individuals who are new to the task.
Final visual acuity was 8/10 with eccentric fixation
. Recovery of blood flow in the occluded arteriole both in fundus examination and fluorescein angiography were noted.
Many people with macular disease naturally adopt eccentric fixation
to a degree for distance objects but may not do so consistently or consciously for a wide range of tasks.
Reading with eccentric fixation
is faster in inferior visual field than in left visual field.
Does the patient consistently fixate centrally or shift to eccentric fixation
when viewing larger images?
2) Patients need to be highly motivated with a clearly defined PRL for eccentric fixation
Of these 188, 149 (79%) had a PRL on SLO testing (called PRL), and 125 (66%) had evidence of an eccentric fixation
locus on face field testing, called ffPL (face field preferred locus); that is, they reported a localized area of blurting or loss of detail with respect to their fixation on the nose.