In order to assess a blind zone margin at the extreme periphery of the temporal half of human retina, comparative
evaluation of the temporal and nasal margins of the visual eld was performed in 16 subjects for several directions of
gaze. The margins were estimated by means of a standard perimeter. The test stimulus was a LED producing a light spot
ickering with frequency 2 Hz. The measurements were carried out for each eye in conditions of gaze xation on the center
of perimeter arc (0°) and on the points shifted temporally by 15–30° to eliminate the occlusion of the nasal visual eld
periphery by the nose usually taking place in standard clinical measurements with 0° direction of gaze. In the standard
measurement conditions, the temporal and nasal margins varied among our subjects in the ranges 78–109° and 57–70°
respectively. In about half of the subjects, no extension of the nasal eld had been found when the xation point was
shifted temporally, indicating that the size of the blind zone corresponded to the di erence of the temporal and nasal
clinical visual elds. However, in 6 subjects, a reliable increase of the nasal visual eld by 5–15° has been revealed
manifesting that not the whole part of the temporal retina shielded by nose is blind. The data obtained indicate the
plausibility of an old hypothesis (Brændstrup, 1948) implying that, at least partially, blindness of the extreme
temporal retina periphery could be considered as a deprivation amblyopia developed due to the occlusion.
nasal visual eld, peripheral blind retina, individual variability, amblyopia
Belokopytov A. V., Rozhkova G. I.
Perimetricheskaya otsenka granitsy slepoi zony na krainei periferii temporalnoi setchatki
[Perimetric assessment of a blind zone margin at the extreme periphery of human temporal retina].
Sensornye sistemy [Sensory systems].
P. 22-30 (in Russian).
- Kovalevsky E.I. Eye diseases. M. Medicine, 1980. 432 p. [in Russian].
- Kravkov S.V. The eye and its work. Moscow- Leningrad. USSR Acad. Sci. 1950. 531 p. [in Russian].
- Rozhkova G.I., Belokopytov A.V., Gracheva M.A. Mysteries of the Blind Zone and Cone-Enriched Rim at the Extreme Periphery of the Human Retina. Sensornye Systemy. 2016. V. 30. N. 4. Р. 263–281 [in Russian].
- Somov E.E. Clinical ophthalmology. M. MEDpress-inform, 2005. 392 p. [in Russian].
- Yarbus A.L. Human visual system. I. Adequate visual stimulus // Biophysics. 1975. V. 20 (5). P. 916–919 [in Russian].
- Yarbus A.L. Eye Movements and Vision. M.: Nauka, 1965. 166 p.
- Brændstrup P. The functional and anatomical di erences between the nasal and temporal parts of the retina // Acta Ophthalmol. 1948. V. 26 (3). P. 351–361.
- Donders F.C. Die Grenzen des Gesichtsfeldes in Beziehung zudenen der Netzhaut / Albrecht. Graef’s Arch Ophthal. 1877. V. 23. P. 255–280.
- Förster R. Uber Gesichtsfeld-Messung // Klinische Monatsblatter fur Augenheilkunde, 1869. B.7. S. 411–415.
- Piltz-Seymour J. R., Heath-Phillip O., Drance S.M. Visual Fields in Glaucoma / Duane’s Ophthalmology on CDROM. 2006. V. 3. Chapter 49.
- To M.P. S., Regan B.C., Wood D., Mollon J.D. Vision out of the corner of the eye // Vision Research. 2011. V. 51 (1). P. 203–214.