Retinal photography is becoming a must in optometric practices. It is not only a tremendous practice builder, but essential in management of the glaucomas. Photographic documentation of diabetic retinopathy patients helps the doctor keep a data base of the progression of the disease, it's on going management and control. There are numerous retinal cameras on the market. The non-mydriatics are mostly limited to the posterior pole while mydriatic cameras do allow photography to the equator and slightly beyond. With the ever changing optometric laws fluorescein angiography will surely become common place in most progressive practices.
Photographic Documentation of Vision Threating Conditions Are A Must.

Superior Branch Retinal Vein Occlusion (BRVO) Of The Left Eye.

1.) Compensating lenses and codes for refractive error

• A. Designation wheel located on the side of the camera:
• 1.} Black dot surrounded by a white background - anterior segment
• 2.} White dot surrounded by a black background - fundus photos
• 3.} Minus sign (-) refractive errors from -10 to -22D - fundus photo
• 4.} Plus sign (+) refractive errors from +8 to +25D - fundus photo

• 2.) Polaroid film types:
• A. Standard 108 film is no longer available 669 is the suggested replacement
• B. Professional 668 and 669 film give better quality photos?
• D. The ASA is = 75

3.) Filter knob located on top of the camera and should be set at 1/3 the other settings are for special photographic techniques other than 35mm or Polaroid standard retinal photography

4.) There is a second filter wheel located on the side of the camera and should normally be set on 1/2 and also has other settings for special photographic techniques such as red-free, and fluorescein angiography.

5.) Patients must be dilated:

A. Fundus magnification is 2.3X with a 30 degree field of view. The 35mm camera has a doubling unit which is mostly for photographing the optic nerve heads and gives a magnification of 4.6X. This is not available on the polaroid camera.

B. With a dilated pupil, one can photograph areas beyond the equator of the eye with good patient cooperation.

6.) Anterior segment photographs have a magnification of 1.6X. One of the main problems with this technique is that one gets a bad reflection in the center of the photograph, however, this is true with any fundus camera.

7.) This camera gives one nearly the same area of view as seen with a binocular indirect ophthalmoscope, but works like a monocular indirect. Everything is up-right and as though seen with a direct ophthalmoscope.

8.) The joy stick is a coarse focusing adjustment. You will find a bright reflection that is right in the center of your field as you move the camera forward. You must continue to move the camera forward until you have passed through this reflection. You should now view the extreme peripheral areas of your view; checking for any grey, bright yellow or orange areas (hot spots) that would indicate that you are no longer centered in the patient's pupil. If there are any of these areas present you can try to make fine adjustments left-right and/or up-down to eliminated them if possible. If this does not work the best thing to do is pull the camera back out and re-align in the center of the pupil and start over. Assuming that you have moved the camera forward without any problems and the peripheral field is clear you should use the fine focusing knob on either side to bring the retinal image into clear focus. The other thing that could be causing the peripheral hot spots might be that the patient's pupil is not dilated enough. You can swivel the camera laterally 30 degrees which allows you to photograph farther out into the peripheral retina.

9.) The Topcon fundus camera has three (3) separate cameras. There is the 35mm for slides and a polaroid for instant feed-back to the patient and you can change these two cameras at any time. The polaroid allows you to take a picture of both the right and left eyes on the same photo which saves money. The third camera has a special barrier filter which allows for fluorescein angiography.

10.) The normal flash settings for our camera, they all are slightly different, are 25 for blond retinas and 50 for darker retinas for both the polaroid and 35mm cameras and 100 for the doubling unit used on the 35mm, 100 is also used on red-free photography 35mm, the polaroid cannot use the doubling unit.

(11.) The first thing you must always do is focus the eyepiece of either camera to help prevent you from accommodating; for if you accommodate the photos will be out of focus. Always start with the focusing eyepiece turned to the extreme left and slowly turn it to the right until the circular reticle just comes into focus.

12.) You should always clean the rollers on the polaroid camera each time you change film. This is a very good practice to get into and will save you a number of headaches.

13.) Once the reticle of the camera has been focus you should give the patient fixation instructions using the fixation target. With the patient's eye dilated center the reticle in the center of the dilated pupil.

Do not be surprised if you can already see some of the retina in view. Follow the instructions given in section #8 for getting a clear full view of the retina. You should be able to photograph the optic nerve head and the macula and more with the 30 degree field. If one has the patient look in different directions you will be able to photograph areas farther in the periphery by swiveling the camera body to the right or left for lateral photographs. To photograph lesions superior or inferior you will have to have the patient move their chin and forehead either slightly forward or backward from the normal position.

Once photographs have been taken you might have a difficult time remembering if the photograph is the right or left eye. In that case remember the fovea is located 1.5 degrees below the horizontal of the optic nerve head. Knowing its anatomical location you can determine which eye you are viewing.
Note:This retinal camera is no longer used in the clinics. Most every retinal camera system is now digital and images are saved and stored on a computer. Having said that I want you to know there is still a place for non-digital type cameras.

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