To the Editor.
—I would like to bring to the attention of our colleagues in ophthalmology a new instrument that I have found to be very adaptable for use in choroidoscopy.1 It is the Nikon Wide-30 ophthalmoscope. The Nikon company advertises the scope for visualizing the retina through a widely dilated pupil, allowing a 30° erect view of the fundus. However, I have used the instrument successfully in performing choroidoscopy, in fiberoptics ophthalmodynamometry,2 and in visualizing the fundus by transillumination through a miotic pupil.3 The instrument performs eminently well in all three modalities.The light of the Wide-30 ophthalmoscope has, of course, to be turned off and a strong cold transillumination light is placed at the lateral canthus or sclera of the patient, which causes the pupil to glow.The instrument is held at a distance of about 17.8 cm in front of the patient's eye, so
Samuel W. Cohen. New Instrument. Arch Ophthalmol. 1979;97(3):571. doi:10.1001/archopht.1979.01020010303032