Visual insignificance of the foveal pit: reassessment of foveal hypoplasia as fovea plana.
OBJECTIVE
To elucidate the visual significance of the foveal pit by measuring foveal architecture and function and to reassess use of the term foveal hypoplasia (as visual acuity can vary among patients who lack a pit).


METHODS
We describe 4 patients who lack a foveal pit. Visual acuities ranged from 20/20 to 20/50. Stratus and Cirrus (Carl Zeiss Meditec, Dublin, California) optical coherence tomographs (OCTs) and multifocal electroretinograms were obtained. High-resolution retinal imaging on 2 of the participants was obtained by using a high-resolution Fourier-domain OCT and an adaptive optics flood-illuminated fundus camera.


RESULTS
No participants had a visible foveal pit with conventional OCT. Central widening of the outer nuclear layer and lengthening of cone outer segments were seen with high-resolution Fourier-domain OCT. Adaptive optics imaging showed normal cone diameters in the central 1 degrees to 2 degrees. Central multifocal electroretinogram responses were normal.


CONCLUSIONS
We show that a foveal pit is not required for foveal cone specialization, anatomically or functionally. This helps to explain the potential for good acuity in the absence of a pit and raises questions about the visual role of the foveal pit. Because the term foveal hypoplasia commonly carries a negative functional implication, it may be more proper to call the anatomic lack of a pit fovea plana.
Marmor
Michael F
MF
Department of Ophthalmology, Stanford University Medical Center, 300 Pasteur Dr, Room A-157, Stanford, CA 94305-5308, USA. marmor@stanford.edu
Choi
Stacey S
SS
Zawadzki
Robert J
RJ
Werner
John S
JS
D000328:Adult; D016115:Albinism, Oculocutaneous / Q000503:physiopathology; D002648:Child; D004596:Electroretinography; D005124:Eye Abnormalities / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D005451:Fluorescein Angiography; D005583:Fourier Analysis; D005584:Fovea Centralis / Q000002:abnormalities*; D006801:Humans; D008297:Male; D010781:Photography; D017949:Retinal Cone Photoreceptor Cells / Q000503:physiopathology*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology*