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Graphics Composition of Fundus Data
GRAPHICS C O M P O S I T I O N O F F U N D U S DATA R O N A L D C. P R U E T T ,
M.D.
Boston, Massachusetts
I developed a simple, inexpensive method of combining and record ing clinical fundus data from a variety of sources in an instant color print or color transparency format. The system is useful for sequential observation, for planning laser treatment, for reference during photocoagulation, and for follow-up in many diseases including macular degeneration. Selecting patients and preparing for laser photocoagulation require careful ophthalmoscopy, biomicroscopy, and study of stereo color photographs and fluorescein angiograms. Angiography permits precise anatomic localization of the targets and is a prerequisite for suc cessful and uncomplicated laser treat ment, particularly for macular lesions. However, locating preselected targets in the fundus can be difficult and inaccurate even after having memorized key land marks when using a contact lens and slit-lamp delivery system. To overcome this problem Gass 1 sug gested mounting a stereoviewer above the slit-lamp oculars and periodically re viewing the fluorescein negative strip during laser delivery. This system re quires the ability to read fluorescein neg atives (dye appears black) and rapidly correlate these data with the color fundus image seen by biomicroscopy. Flower and Patz 2 constructed a special viewer mounted on a slit lamp in which a single color transparency and a fluorescein angiogram showing the same fundus area
Accepted for publication Sept. 17, 1984. From the Eye Research Institute of Retina Founda tion and Retina Associates, Boston, Massachusetts. This study was supported in part by the Massachu setts Lions Eye Research Fund, Inc. Reprint requests to Library, Eye Research Institute, 20 Staniford St., Boston, MA 02114. 728
are placed 90° from one another. Inde pendently variable illumination of the transparency and the angiogram, carriag es for correction of image orientation disparity, and a beam splitter allow su perimposition of the two slides. Although a binocular device can be attached, the resulting view of the superimposed slides is not stereoscopic. The commercial McAdams angioprojector device was de signed for use with the Britt laser photocoagulator. A variable light source, contained in a small box, was connected by a fiberoptic cable to a projector mounted on a slit lamp. This projected a single 35-mm slide of any type into one ocular of the biomicroscope. By adjusting the illumination, the projected image seen with one eye could be superimposed on the fundus image seen with the other eye. Unfortunately, stereopsis was impos sible, the patients' eye movements caused frequent misalignment, the sys tem was expensive, and it is no longer available. I have used two systems for evaluating and treating patients and for clinical re search. The first3 includes a color-keyed drawing of the posterior fundus made before photocoagulation by projecting a color image on paper and sketching the outlines of the optic disk, the retinal vessels, and other landmarks. One or several fluorescein angiograms are then projected onto the same paper, which can
©AMERICAN JOURNAL OF OPHTHALMOLOGY 98:728-731, 1984
VOL. 98, NO. 6
GRAPHICS COMPOSITION OF FUNDUS DATA
be moved to correct the orientation, and photocoagulation targets are noted on the sketch. No special equipment is needed and comparisons can be made between fundus abnormalities and plotted visual field defects (photofield mapping). The latter capability is useful in planning treatment and investigating different laser techniques. However, mental trans lation must be made between the colorkeyed abstraction and the fundus details seen by biomicroscopy during treatment. I developed a recording and planning method that provides composite clinical data in a color fundus format and can be combined with photofield mapping. The system can be applied to the study of macular degeneration as well as other clinical problems, including optic disk and nerve fiber changes in patients with glaucoma, tumor growth, retinal neovascularization, and posterior progression of a retinoschisis cavity.
729
projection can be changed easily. Indi vidual transparent fluorescein prints can be used or the fluorescein transit nega tive strip can be placed on a reel and wound through the projector for selecting appropriate frames. First, a fluorescein angiogram is pro jected. An 8Y2 x 11-inch sheet of clear cellulose material is placed over the pro jection screen, where it is held by mag netic strips fastened to the screen with plastic adhesive tape. A water-insoluble, black, felt-tipped laundry marker is used to outline the optic disk margin, several major retinal blood vessels, and the fovea on the cellulose overlay (Fig. 1). Treat ment targets such as neovascular mem branes, choroidal leaks, and retinal pig-
M A T E R I A L AND M E T H O D S
Slide selection—Stereo pairs of 35-mm color transparencies showing the lesion are examined using a hand-held illumi nated viewer, and the best slides are selected. An 8Y2 x 11-inch transparent positive contact print of the entire fluorescein transit is also studied stereoscopically using +8.00-diopter glasses and rear illumination. The most informative angiograms are clipped from this sheet and slipped into plastic mounts. Other types of fundus transparencies (for example, monochromatic) taken with the same magnification are viewed, clipped, and mounted similarly. Data composition—Several rear pro jectors are suitable for data composition. I use the Keeler Medical Viewer GR-8, which provides 8 x and 20 X magnifica tions and has a 150-W halogen light source. For most cases, 8 x magnification is preferable. Slides for composition are inserted in a plastic slide stick so that the
Fig. 1 (Pruett). Key fundus landmarks and laser targets noted with a felt-tipped laundry marker using rear projection and an acetate overlay. Data are extracted from multiple sources (color, red-free, and monochromatic photographs and fluorescein angiograms) by orienting the magnetically held overlay.
730
AMERICAN JOURNAL OF OPHTHALMOLOGY
ment epithelial detachments are noted, and the patient's name, the eye, and the date of photography are recorded in one corner. Several angiograms are compared in succession to confirm the abnormali ties and their locations relative to the chosen landmarks. Even if only a portion of the first angiographie field is visible in subsequent slides, the cellulose overlay can be properly oriented for each slide projected and the information added. Monochromatic photographs are helpful for locating the yellow pigment most con centrated in the fovea and for checking the anatomic locations and tissue depth of lesions. When data extraction is complete, the original color slide of the area is dis played. By moving the cellulose overlay, the composited information can be super imposed on the color reproduction of the fundus (Fig. 2). This is photographed by one of two methods. A glossy 2% X 3%-inch color image can be produced in minutes using a Kodak Instagraphic CRT Imaging Outfit with Model 12 light-shield cone (Eastman Kodak Co., 800 Lee Rd., Rochester, NY 14650), or a transparency can be made using a 35-mm camera with the same cone (Fig. 3). Viewing this transparency, together with a stereo mate showing the same field, gives a stereo scopic color image of the lesion showing the overlay data. Transparencies are usu ally available from commercial laborato ries within 24 hours and can be projected for photofield mapping. 3 The camera sys tem is prefocused, and exposure can be varied for different film densities. Wideangle color photographs, monochromatic slides, and fluorescein angiograms can also be composited by the same tech nique. After composition and photogra phy, the overlay sheet can be erased with an alcohol sponge and reused or can be filed in the patient's record. Application—An instant color print, a single slide or a stereo pair of color trans parencies, or both a print and slides can
DECEMBER, 1984
Fig. 2 (Pruett). Composited data with patient and eye identification and date superimposed on color fundus photograph to display laser treatment plan.
Fig. 3 (Pruett). Photography of projector display using light-shield cone to produce an instant color print or stereo 35-mm color transparencies.
VOL. 98, NO. 6
GRAPHICS COMPOSITION OF FUNDUS DATA
731
attention to targets that may not have been treated according to plan and also helps pinpoint new lesions. I file the overlay permanently in the patient's rec ord for this purpose. DISCUSSION
Fig. 4 (Pruett). Simply modified, battery-powered hand stereoviewer for print or transparencies can be mounted on a slit lamp for use during laser delivery.
be conveniently displayed during photocoagulation using a slightly modified battery-powered stereoviewer. Attaching the viewer to the biomicroscope is op tional but desirable and must be adapted to the particular laser instrument. I sub stituted a toggle switch for a finger de pression switch so that the viewer could be kept on without touching it. A small aperture over the lamp illuminates the color print, which is held by a bent paper clip cemented to the top of the housing with epoxy glue (Fig. 4). Before and dur ing treatment, the composited illustra tions can be referred to frequently to help identify laser targets and to avoid unwanted treatment of other areas. The fundus image seen in the viewer is the same as that in the biomicroscope with the addition of the pretreatment nota tions. Color transparencies of the fundus taken immediately after treatment and subsequent transparencies and fluorescein angiograms can be displayed on the projector screen and compared with the pretreatment plan recorded on the cellu lose overlay sheet. This method draws
This inexpensive system uses rear pro jection and overlay compilation of graph ic data from multiple sources, including stereoscopic color photographs, fluorescein angiograms, and red-free, infrared, 4 and monochromatic 6 photographs, and can be used in a wide-angle format. 6 Several examiners can observe and cri tique the composition process simultane ously while formulating a treatment plan that is recorded on an instant color print or on color transparencies that present the same topography as that seen during treatment. A color transparency can be used in photofield mapping, and both photographic recording methods can be used in management and follow-up of many clinical problems in addition to macular degeneration. REFERENCES 1. Gass, J. D. M.: Stereoscopic Atlas of Macular Diseases. Diagnosis and Treatment, 2nd ed. St. Louis, C. V. Mosby, 1977, pp. 385 and 386. 2. Flower, R. W., and Patz, A.: A viewer for correlation of fluorescein and color fundus photo graphs. Invest. Ophthalmol. 13:398, 1974. 3. Avila, M. P., Jalkh, A. E., Mainster, M. A., Trempe, C. L., Weiter, J. J., and Schepens, C. L.: Photofield mapping in the evaluation and manage ment of subretinal neovascularization. Ann. Ophthal mol. In press. 4. Dallow, R. L., and McMeel, J. W.: Infrared photography of the ocular fundus. In Pruett, R. C , and Regan, C. D. J. (eds.): Retina Congress. New York, Appleton-Century-Crofts, 1974, pp. 125-133. 5. Gragoudas, E. S., Delori, F. C , and Pruett, R. C : Examination of the macula in monochromatic light. In Freeman, H. M., Hirose, T., and Schepens, C. L. (eds.): Vitreous Surgery and Advances in Fun dus Diagnosis and Treatment. New York, AppletonCentury-Crofts, 1977, pp. 613-624. 6. Nussbaum, J., Schepens, C. L., and Pruett, R. C : Wide-angle fundus photo-illustration. Oph thalmic Surg. 15:588, 1984.
M.D.
Boston, Massachusetts
I developed a simple, inexpensive method of combining and record ing clinical fundus data from a variety of sources in an instant color print or color transparency format. The system is useful for sequential observation, for planning laser treatment, for reference during photocoagulation, and for follow-up in many diseases including macular degeneration. Selecting patients and preparing for laser photocoagulation require careful ophthalmoscopy, biomicroscopy, and study of stereo color photographs and fluorescein angiograms. Angiography permits precise anatomic localization of the targets and is a prerequisite for suc cessful and uncomplicated laser treat ment, particularly for macular lesions. However, locating preselected targets in the fundus can be difficult and inaccurate even after having memorized key land marks when using a contact lens and slit-lamp delivery system. To overcome this problem Gass 1 sug gested mounting a stereoviewer above the slit-lamp oculars and periodically re viewing the fluorescein negative strip during laser delivery. This system re quires the ability to read fluorescein neg atives (dye appears black) and rapidly correlate these data with the color fundus image seen by biomicroscopy. Flower and Patz 2 constructed a special viewer mounted on a slit lamp in which a single color transparency and a fluorescein angiogram showing the same fundus area
Accepted for publication Sept. 17, 1984. From the Eye Research Institute of Retina Founda tion and Retina Associates, Boston, Massachusetts. This study was supported in part by the Massachu setts Lions Eye Research Fund, Inc. Reprint requests to Library, Eye Research Institute, 20 Staniford St., Boston, MA 02114. 728
are placed 90° from one another. Inde pendently variable illumination of the transparency and the angiogram, carriag es for correction of image orientation disparity, and a beam splitter allow su perimposition of the two slides. Although a binocular device can be attached, the resulting view of the superimposed slides is not stereoscopic. The commercial McAdams angioprojector device was de signed for use with the Britt laser photocoagulator. A variable light source, contained in a small box, was connected by a fiberoptic cable to a projector mounted on a slit lamp. This projected a single 35-mm slide of any type into one ocular of the biomicroscope. By adjusting the illumination, the projected image seen with one eye could be superimposed on the fundus image seen with the other eye. Unfortunately, stereopsis was impos sible, the patients' eye movements caused frequent misalignment, the sys tem was expensive, and it is no longer available. I have used two systems for evaluating and treating patients and for clinical re search. The first3 includes a color-keyed drawing of the posterior fundus made before photocoagulation by projecting a color image on paper and sketching the outlines of the optic disk, the retinal vessels, and other landmarks. One or several fluorescein angiograms are then projected onto the same paper, which can
©AMERICAN JOURNAL OF OPHTHALMOLOGY 98:728-731, 1984
VOL. 98, NO. 6
GRAPHICS COMPOSITION OF FUNDUS DATA
be moved to correct the orientation, and photocoagulation targets are noted on the sketch. No special equipment is needed and comparisons can be made between fundus abnormalities and plotted visual field defects (photofield mapping). The latter capability is useful in planning treatment and investigating different laser techniques. However, mental trans lation must be made between the colorkeyed abstraction and the fundus details seen by biomicroscopy during treatment. I developed a recording and planning method that provides composite clinical data in a color fundus format and can be combined with photofield mapping. The system can be applied to the study of macular degeneration as well as other clinical problems, including optic disk and nerve fiber changes in patients with glaucoma, tumor growth, retinal neovascularization, and posterior progression of a retinoschisis cavity.
729
projection can be changed easily. Indi vidual transparent fluorescein prints can be used or the fluorescein transit nega tive strip can be placed on a reel and wound through the projector for selecting appropriate frames. First, a fluorescein angiogram is pro jected. An 8Y2 x 11-inch sheet of clear cellulose material is placed over the pro jection screen, where it is held by mag netic strips fastened to the screen with plastic adhesive tape. A water-insoluble, black, felt-tipped laundry marker is used to outline the optic disk margin, several major retinal blood vessels, and the fovea on the cellulose overlay (Fig. 1). Treat ment targets such as neovascular mem branes, choroidal leaks, and retinal pig-
M A T E R I A L AND M E T H O D S
Slide selection—Stereo pairs of 35-mm color transparencies showing the lesion are examined using a hand-held illumi nated viewer, and the best slides are selected. An 8Y2 x 11-inch transparent positive contact print of the entire fluorescein transit is also studied stereoscopically using +8.00-diopter glasses and rear illumination. The most informative angiograms are clipped from this sheet and slipped into plastic mounts. Other types of fundus transparencies (for example, monochromatic) taken with the same magnification are viewed, clipped, and mounted similarly. Data composition—Several rear pro jectors are suitable for data composition. I use the Keeler Medical Viewer GR-8, which provides 8 x and 20 X magnifica tions and has a 150-W halogen light source. For most cases, 8 x magnification is preferable. Slides for composition are inserted in a plastic slide stick so that the
Fig. 1 (Pruett). Key fundus landmarks and laser targets noted with a felt-tipped laundry marker using rear projection and an acetate overlay. Data are extracted from multiple sources (color, red-free, and monochromatic photographs and fluorescein angiograms) by orienting the magnetically held overlay.
730
AMERICAN JOURNAL OF OPHTHALMOLOGY
ment epithelial detachments are noted, and the patient's name, the eye, and the date of photography are recorded in one corner. Several angiograms are compared in succession to confirm the abnormali ties and their locations relative to the chosen landmarks. Even if only a portion of the first angiographie field is visible in subsequent slides, the cellulose overlay can be properly oriented for each slide projected and the information added. Monochromatic photographs are helpful for locating the yellow pigment most con centrated in the fovea and for checking the anatomic locations and tissue depth of lesions. When data extraction is complete, the original color slide of the area is dis played. By moving the cellulose overlay, the composited information can be super imposed on the color reproduction of the fundus (Fig. 2). This is photographed by one of two methods. A glossy 2% X 3%-inch color image can be produced in minutes using a Kodak Instagraphic CRT Imaging Outfit with Model 12 light-shield cone (Eastman Kodak Co., 800 Lee Rd., Rochester, NY 14650), or a transparency can be made using a 35-mm camera with the same cone (Fig. 3). Viewing this transparency, together with a stereo mate showing the same field, gives a stereo scopic color image of the lesion showing the overlay data. Transparencies are usu ally available from commercial laborato ries within 24 hours and can be projected for photofield mapping. 3 The camera sys tem is prefocused, and exposure can be varied for different film densities. Wideangle color photographs, monochromatic slides, and fluorescein angiograms can also be composited by the same tech nique. After composition and photogra phy, the overlay sheet can be erased with an alcohol sponge and reused or can be filed in the patient's record. Application—An instant color print, a single slide or a stereo pair of color trans parencies, or both a print and slides can
DECEMBER, 1984
Fig. 2 (Pruett). Composited data with patient and eye identification and date superimposed on color fundus photograph to display laser treatment plan.
Fig. 3 (Pruett). Photography of projector display using light-shield cone to produce an instant color print or stereo 35-mm color transparencies.
VOL. 98, NO. 6
GRAPHICS COMPOSITION OF FUNDUS DATA
731
attention to targets that may not have been treated according to plan and also helps pinpoint new lesions. I file the overlay permanently in the patient's rec ord for this purpose. DISCUSSION
Fig. 4 (Pruett). Simply modified, battery-powered hand stereoviewer for print or transparencies can be mounted on a slit lamp for use during laser delivery.
be conveniently displayed during photocoagulation using a slightly modified battery-powered stereoviewer. Attaching the viewer to the biomicroscope is op tional but desirable and must be adapted to the particular laser instrument. I sub stituted a toggle switch for a finger de pression switch so that the viewer could be kept on without touching it. A small aperture over the lamp illuminates the color print, which is held by a bent paper clip cemented to the top of the housing with epoxy glue (Fig. 4). Before and dur ing treatment, the composited illustra tions can be referred to frequently to help identify laser targets and to avoid unwanted treatment of other areas. The fundus image seen in the viewer is the same as that in the biomicroscope with the addition of the pretreatment nota tions. Color transparencies of the fundus taken immediately after treatment and subsequent transparencies and fluorescein angiograms can be displayed on the projector screen and compared with the pretreatment plan recorded on the cellu lose overlay sheet. This method draws
This inexpensive system uses rear pro jection and overlay compilation of graph ic data from multiple sources, including stereoscopic color photographs, fluorescein angiograms, and red-free, infrared, 4 and monochromatic 6 photographs, and can be used in a wide-angle format. 6 Several examiners can observe and cri tique the composition process simultane ously while formulating a treatment plan that is recorded on an instant color print or on color transparencies that present the same topography as that seen during treatment. A color transparency can be used in photofield mapping, and both photographic recording methods can be used in management and follow-up of many clinical problems in addition to macular degeneration. REFERENCES 1. Gass, J. D. M.: Stereoscopic Atlas of Macular Diseases. Diagnosis and Treatment, 2nd ed. St. Louis, C. V. Mosby, 1977, pp. 385 and 386. 2. Flower, R. W., and Patz, A.: A viewer for correlation of fluorescein and color fundus photo graphs. Invest. Ophthalmol. 13:398, 1974. 3. Avila, M. P., Jalkh, A. E., Mainster, M. A., Trempe, C. L., Weiter, J. J., and Schepens, C. L.: Photofield mapping in the evaluation and manage ment of subretinal neovascularization. Ann. Ophthal mol. In press. 4. Dallow, R. L., and McMeel, J. W.: Infrared photography of the ocular fundus. In Pruett, R. C , and Regan, C. D. J. (eds.): Retina Congress. New York, Appleton-Century-Crofts, 1974, pp. 125-133. 5. Gragoudas, E. S., Delori, F. C , and Pruett, R. C : Examination of the macula in monochromatic light. In Freeman, H. M., Hirose, T., and Schepens, C. L. (eds.): Vitreous Surgery and Advances in Fun dus Diagnosis and Treatment. New York, AppletonCentury-Crofts, 1977, pp. 613-624. 6. Nussbaum, J., Schepens, C. L., and Pruett, R. C : Wide-angle fundus photo-illustration. Oph thalmic Surg. 15:588, 1984.