Abstract
Purpose: :
The Preferential Hyperacuity Perimeter (PHP) is a noninvasive and noncontact exam, evaluating macular perimetry, based on the human visual function of hyperacuity. PHP has the capability of detecting functional changes and was designed for the early detection of central and paracentral alterations in the visual field, such as those in patients with AMD. Microperimetry (MP) is a complementary diagnostic tool that aids in the assessment of the visual function and its relation to the structural changes of the retina and fovea. MP is an add-on feature of Spectral OCT/SLO (OPKO/OTI, Miami, FL, USA) and runs simultaneously with the SLO imaging and provides real time tracking of retinal movement and patient fixation, and performs mapping of the macular blind spots.
Methods: :
Patients with a variety of ocular diseases underwent PHP and MP tests on the same day. PHP results were superimposed on MP maps and the correlation between the two tests was evaluated. "Seen" distortions, representing metamorphopsia and "not-seen" distortions, representing scotoma were assessed and graded by PHP and afterwards were compared to corresponding loci of numeric MP values.
Results: :
The comparative analysis of the data acquired in 7 patients using two devices showed good correlation between PHP and MP in the areas of impaired retinal sensitivity as a result of local retinal pathology.
Conclusions: :
Both devices (PHP or MP) were found to be sensitive in detection of retinal functional pathology. Both machines provided quantitative data of qualitative impairment of vision and can be used for close monitoring of functional retinal changes and for detection of progression in a variety of patients with retinal diseases.
Keywords: imaging/image analysis: clinical • macula/fovea • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)