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Visual Field Defect Associated with Choroidal Nevus
VISUAL F I E L D DEFECT ASSOCIATED W I T H CHOROIDAL N E V U S G. NAUMANN,* M.D.,
L. E. ZIMMERMAN, 1 ' M.D., AND M. YANOFF,*
M.D.
Washington, D.C. Nevi of the choroid usually do not pro duce a field defect, although a scotoma cor responding to the site of the lesion may be demonstrated in occasional cases.1"4 Tamler and Maumenee,5 in their series of 42 choroidal nevi, found corresponding de fects of the visual field in 15 cases ( 3 8 % ) . They remarked that "it is not clear at the present time how one can explain a field de fect, even relative, on the basis of a histological picture of noninvolvement of the ret ina and choriocapillaris." It is the purpose of this report to record a case in which a nevus of the choroid pro duced degenerative changes in the overlying retina accounting for an absolute scotoma that had been demonstrated clinically. CASE REPORT
The patient, a 32-year-old white nurse, had been in good general health until two weeks prior to admission, when she first noted blurring of vi sion in her left eye. Mild at first, the visual dis turbance seemed to be getting worse "every day." On the day of admission she recalled being "bumped" in the eye while arranging the pillows of a patient. Vision was 20/15, R.E., 20/30, L.E. Tension was 17 mm Hg in both eyes. The right eye was entirely unremarkable. Slitlamp examination of the left eye showed no abnormality in the ante rior segment or in the vitreous. Ophthalmoscopy revealed a subretinal lesion elevated 0.5 diopter and measuring two to three disc diameters in From the Registry of Ophthalmic Pathology, Armed Forces Institute of Pathology. * Fellow in Ophthalmic Pathology, Armed Forces Institute of Pathology, supported by Deutsche Forschungsgemeinschaft (German Research Society) grant NA 55/1 from Bad Godesberg, Germany, on leave from the University Eye Hospital, Hamburg. t Chief, Ophthalmic Pathology Branch, Armed Forces Institute of Pathology. t Fellow in Ophthalmic Pathology, Armed Forces Institute of Pathology, supported by a Public Health Service training grant, 5 T l NB 5379-03, from the National Institute of Neurological Diseases and Blindness, Public Health Service. Present address: Departments of Ophthalmology and Pathology, Hos pital of the University of Pennsylvania, Phila delphia, Pennsylvania. 914
size, extending below the nervehead between the 4:30- and 7-o'clock positions. The retina sur rounding the lesion appeared yellow, while the perimacular region had a slightly velvety, edematous appearance. Examination of the visual field of her left eye revealed an absolute scotoma in connection with the blindspot (fig. 1). A diag nosis of malignant melanoma of the choroid was made and the left eye was enucleated. After fixation, the enucleated eye was opened so as to include the choroidal lesion in an oblique plane passing through the optic disc and pupil. Macroscopically a pigmented tumor measuring 2.5 mm in diameter was seen in the choroid adjacent to the optic disc. Retinal folds were present in the macular area. Microscopic examination reveals an essentially normal globe except for the presence of a pig mented tumor in the juxtapapillary choroid inte riorly (fig. 2). The choroidal tumor has a thick ness of 0.5 mm. It is composed of plump poly hedral and fusiform nevus cells that are rather heavily pigmented and of slender spindle nevus cells6 that contain little or no pigment (fig. 3). The latter are located mainly in the outer half of the lesion. There are also scattered balloon nevus cells.6 The choriocapillaris is compressed but not obliterated. The pigment epithelium of the retina appears edematous and beginning proliferation can be seen. The extent of definite morphologic alterations
Fig. 1 (Naumann, Zimmerman and Yanoff). Cen tral visual field, left eye, tested with 2-mm white test object at 1.0 meter distance. An absolute sco toma extends upward from the blindspot.
VOL. 62, NO. 5
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VISUAL FIELDS IN CHOROIDAL NEVUS
Fig. 2 (Naumann, Zimmerman and Yanoff). Juxtapapillary nevus of inferotemporal choroid with marked degeneration of overlying retina. Arrow indicates junction be tween essentially normal and de generated retina, shown at higher magnification in Figure 4-A. The retinal separation is artifactitious. (Hematoxylin-eosin, XlO, AFIP Neg. 65-5944.)
Fig. 3 (Naumann, Zimmerman and Yanoff). (A) The nevus is composed of plump polyhedral and fusiform cells located mainly, but not exclusively, along the inner edge of the tumor and slender spindle cells (Hematoxylin-eosin, X145, AFIP Neg. 65-3979). (B) A repre sentative field at greater magnifica tion (X395) reveals the tumor cells to be perfectly benign. (AFIP Neg. 65-3980.)
\ y
916
AMERICAN JOURNAL OF OPHTHALMOLOGY
,-.x*to»tf;->i*'.. , .j. .';«
NOVEMBER, 1966
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Fig. 4 (Naumann, Zimmerman and Yanoff). (A) Peripheral edge of degenerated retina shown by arrow in Figure 2. At the right the retina appears essentially normal. (Hematoxylin-eosin, original XSS, AFIP Neg. 65-3158.) (B) Degenerated retina overlying the choroidal nevus. There is marked dis organization of the outer retinal layers and the rods and cones have completely disappeared. (Hematoxy lin-eosin, original X140, AFIP Neg. 65-3158.) in the retina is significantly greater than the nevus itself (fig 2). Figure 4-A shows the junc tion of essentially normal and degenerated retina, the latter exhibiting loss of rod and cones, almost complete absence of the outer nuclear layer, edema of the outer plexiform layer, and diminu tion of the inner nuclear layer. Figure 4-B re veals the most pronounced alterations, observed directly over the choroidal nevus: only the nervefiber layer and a few ganglion cells and bipolar cells are preserved, while the outer layers have virtually disappeared. The patient was reported alive and healthy 22 years after enucleation. COMMENT
Theoretically there are at least three pos sible retinal mechanisms for the production of a scotoma: 1. There may be a temporary and partial impairment of retinal reception either by previous excessive stimulation (like daz zling) or transitory discontinuity of blood circulation (for example, migraine ophthalmique, amaurosis fugax) without morpho logic evidence of damage to the retinal structure. 2. The normally functioning retina may be moved away from the focal plane of the
eye, either "out," for example, by an ectatic lesion,7 or "in" by lesions of the choroid. Both possibilities are examples of "refrac tional scotoma." 3. The retina suffers such pronounced damage that it can be recognized by histologic means. We believe that all three mechanisms may be responsible for scotomas associated with nevi of the choroid. The first possibility may come into play when the visual field is checked after a nevus has been discovered and studied with intense ophthalmoscopic illumination. It is interesting in this respect that Tamler and Maumenee,5 who found such a high incidence of scotomas in their series of nevi (15 out of 42), specifically mentioned the fact that in some cases pre vious to perimetry strong light (the giant ophthalmoscope) was used in evaluating the choroidal lesion in question and that some times the scotoma could not be found when such an ophthalmoscopic examination did not precede the visual field study. Nevi exceeding the thickness of the nor mal choroid expand mainly toward the ret-
VOL. 62, NO. 5
VISUAL FIELDS IN CHOROIDAL NEVUS
ina. Thus the retina overlying the nevus is moved to a different level and "out of focus" and is therefore rendered relatively hyperopic in comparison with the rest of the retina. This probably is negligible while testing with large targets but must be recog nizable with minute targets, particularly in the central area of the nevus, where the ele vation is highest. Accordingly these scotomas are relative in that they can be elicited only with small targets 5 and are smaller than would be expected from the size of the lesion.8 We do not feel that the two mechanisms just mentioned have any bearing on the visual field defect in our particular case. Our report illustrates that a benign pigmented nevus of the choroid does have the potential to cause pronounced retinal degen eration and thus produce not only a relative but even an absolute scotoma of the visual field. We can only speculate on how these changes develop. The choriocapillaris, al though narrowed, is not obliterated, and one therefore must postulate a competition for nutritional material between the nevus cells and the sensory retina. The occurrence of relative scotomas in association with choroidal nevi is well docu mented, although several authors9"13 have not observed such visual field defects, but almost all ophthalmologists doubt that abso lute scotomas can be attributed to benign melanotic lesions. The demonstration of an absolute scotoma corresponding to a lesion suspected of being either a nevus or a ma lignant melanoma is generally interpreted as reliable evidence that the lesion in question is malignant and that enucleation is jus tified. The present case, we believe, indi cates that exceptions to this rule may be en countered and that additional biologic evi dence of malignancy (for example, progres sive growth) should be obtained before a
917
small suspicious tumor is treated by enuclea tion. SUMMARY
A case of nevus of the choroid with corre sponding absolute visual field defect is re ported. The histopathologic characteristics of the tumor and the degenerative changes in the retina overlying it are described. Thus, the mechanism for the production of an absolute scotoma is illustrated. Armed Forces Institute of Pathology (20305) REFERENCES
1. Bettman, J. W., and Fellows, V.: Differential diagnosis of dark lesions of posterior fundus. Am. J. Ophth. 41:97S, 1956. 2. Hogan, M. J.: Clinical aspects, management and prognosis of melanomas of the uvea and optic nerve. In Boniuk, M. (ed.) : Ocular and Adnexal Tumors. St. Louis, Mosby, 1964, pp. 203-302. 3. Katzin, H. M.: Cited by Hogan.' 4. Reese, A. B.: Tumors of the Eye. New York, Hoeber, 1951. 5. Tamler, E., and Maumenee, A. E.: Clinical study of choroidal nevi. Arch. Ophth. 62:196, 1959. 6. Naumann, G., Yanoff, M., and Zimmerman, L. E.: Histogenesis of malignant melanoma of the uvea: I. Histopathologic characteristics of nevi of the choroid and ciliary body. Arch. Ophth., in press. 7. Kruse, W., and Utermann, D.: Beitrag zur Erkennung refraktionsbedingter Skotome. Klin. Mbl. Augen. 143 :247, 1963. 8. Reese, A. B., and Jones, I. S.: Differential diagnosis of malignant melanoma of choroid. Arch. Ophth. 58:477, 1957. 9. Albers, E. C.: Benign melanomas of choroid and their malignant transformation. Am J. Ophth. 23 :779, 1940. 10. Ballantyne, A. J., and Michaelson, I. C.: Textbook of the Fundus of the Eye. Baltimore, Williams & Wilkins, 1962. 11. Blodi, F.: Melanoma. In Sorsby, A.(ed.) : Modern Ophthalmology. Washington, Butterworth, 1964, p. 344-380. 12. Moore, R. F.: Four cases of melanoma of the choroid, with a pathological examination in one case; and one case of unusual chronicity, after dissemination of a melanotic sarcoma had occurred. Roy. Lond. Ophth. Rep. 19:411, 1914. 13. Stallard, H. B.: Diseases of the choroid. In Berens, C.(ed.): The Eye and Its Diseases. Phil adelphia, Saunders, ed. 2, 1949.
L. E. ZIMMERMAN, 1 ' M.D., AND M. YANOFF,*
M.D.
Washington, D.C. Nevi of the choroid usually do not pro duce a field defect, although a scotoma cor responding to the site of the lesion may be demonstrated in occasional cases.1"4 Tamler and Maumenee,5 in their series of 42 choroidal nevi, found corresponding de fects of the visual field in 15 cases ( 3 8 % ) . They remarked that "it is not clear at the present time how one can explain a field de fect, even relative, on the basis of a histological picture of noninvolvement of the ret ina and choriocapillaris." It is the purpose of this report to record a case in which a nevus of the choroid pro duced degenerative changes in the overlying retina accounting for an absolute scotoma that had been demonstrated clinically. CASE REPORT
The patient, a 32-year-old white nurse, had been in good general health until two weeks prior to admission, when she first noted blurring of vi sion in her left eye. Mild at first, the visual dis turbance seemed to be getting worse "every day." On the day of admission she recalled being "bumped" in the eye while arranging the pillows of a patient. Vision was 20/15, R.E., 20/30, L.E. Tension was 17 mm Hg in both eyes. The right eye was entirely unremarkable. Slitlamp examination of the left eye showed no abnormality in the ante rior segment or in the vitreous. Ophthalmoscopy revealed a subretinal lesion elevated 0.5 diopter and measuring two to three disc diameters in From the Registry of Ophthalmic Pathology, Armed Forces Institute of Pathology. * Fellow in Ophthalmic Pathology, Armed Forces Institute of Pathology, supported by Deutsche Forschungsgemeinschaft (German Research Society) grant NA 55/1 from Bad Godesberg, Germany, on leave from the University Eye Hospital, Hamburg. t Chief, Ophthalmic Pathology Branch, Armed Forces Institute of Pathology. t Fellow in Ophthalmic Pathology, Armed Forces Institute of Pathology, supported by a Public Health Service training grant, 5 T l NB 5379-03, from the National Institute of Neurological Diseases and Blindness, Public Health Service. Present address: Departments of Ophthalmology and Pathology, Hos pital of the University of Pennsylvania, Phila delphia, Pennsylvania. 914
size, extending below the nervehead between the 4:30- and 7-o'clock positions. The retina sur rounding the lesion appeared yellow, while the perimacular region had a slightly velvety, edematous appearance. Examination of the visual field of her left eye revealed an absolute scotoma in connection with the blindspot (fig. 1). A diag nosis of malignant melanoma of the choroid was made and the left eye was enucleated. After fixation, the enucleated eye was opened so as to include the choroidal lesion in an oblique plane passing through the optic disc and pupil. Macroscopically a pigmented tumor measuring 2.5 mm in diameter was seen in the choroid adjacent to the optic disc. Retinal folds were present in the macular area. Microscopic examination reveals an essentially normal globe except for the presence of a pig mented tumor in the juxtapapillary choroid inte riorly (fig. 2). The choroidal tumor has a thick ness of 0.5 mm. It is composed of plump poly hedral and fusiform nevus cells that are rather heavily pigmented and of slender spindle nevus cells6 that contain little or no pigment (fig. 3). The latter are located mainly in the outer half of the lesion. There are also scattered balloon nevus cells.6 The choriocapillaris is compressed but not obliterated. The pigment epithelium of the retina appears edematous and beginning proliferation can be seen. The extent of definite morphologic alterations
Fig. 1 (Naumann, Zimmerman and Yanoff). Cen tral visual field, left eye, tested with 2-mm white test object at 1.0 meter distance. An absolute sco toma extends upward from the blindspot.
VOL. 62, NO. 5
915
VISUAL FIELDS IN CHOROIDAL NEVUS
Fig. 2 (Naumann, Zimmerman and Yanoff). Juxtapapillary nevus of inferotemporal choroid with marked degeneration of overlying retina. Arrow indicates junction be tween essentially normal and de generated retina, shown at higher magnification in Figure 4-A. The retinal separation is artifactitious. (Hematoxylin-eosin, XlO, AFIP Neg. 65-5944.)
Fig. 3 (Naumann, Zimmerman and Yanoff). (A) The nevus is composed of plump polyhedral and fusiform cells located mainly, but not exclusively, along the inner edge of the tumor and slender spindle cells (Hematoxylin-eosin, X145, AFIP Neg. 65-3979). (B) A repre sentative field at greater magnifica tion (X395) reveals the tumor cells to be perfectly benign. (AFIP Neg. 65-3980.)
\ y
916
AMERICAN JOURNAL OF OPHTHALMOLOGY
,-.x*to»tf;->i*'.. , .j.
NOVEMBER, 1966
'«M<
Fig. 4 (Naumann, Zimmerman and Yanoff). (A) Peripheral edge of degenerated retina shown by arrow in Figure 2. At the right the retina appears essentially normal. (Hematoxylin-eosin, original XSS, AFIP Neg. 65-3158.) (B) Degenerated retina overlying the choroidal nevus. There is marked dis organization of the outer retinal layers and the rods and cones have completely disappeared. (Hematoxy lin-eosin, original X140, AFIP Neg. 65-3158.) in the retina is significantly greater than the nevus itself (fig 2). Figure 4-A shows the junc tion of essentially normal and degenerated retina, the latter exhibiting loss of rod and cones, almost complete absence of the outer nuclear layer, edema of the outer plexiform layer, and diminu tion of the inner nuclear layer. Figure 4-B re veals the most pronounced alterations, observed directly over the choroidal nevus: only the nervefiber layer and a few ganglion cells and bipolar cells are preserved, while the outer layers have virtually disappeared. The patient was reported alive and healthy 22 years after enucleation. COMMENT
Theoretically there are at least three pos sible retinal mechanisms for the production of a scotoma: 1. There may be a temporary and partial impairment of retinal reception either by previous excessive stimulation (like daz zling) or transitory discontinuity of blood circulation (for example, migraine ophthalmique, amaurosis fugax) without morpho logic evidence of damage to the retinal structure. 2. The normally functioning retina may be moved away from the focal plane of the
eye, either "out," for example, by an ectatic lesion,7 or "in" by lesions of the choroid. Both possibilities are examples of "refrac tional scotoma." 3. The retina suffers such pronounced damage that it can be recognized by histologic means. We believe that all three mechanisms may be responsible for scotomas associated with nevi of the choroid. The first possibility may come into play when the visual field is checked after a nevus has been discovered and studied with intense ophthalmoscopic illumination. It is interesting in this respect that Tamler and Maumenee,5 who found such a high incidence of scotomas in their series of nevi (15 out of 42), specifically mentioned the fact that in some cases pre vious to perimetry strong light (the giant ophthalmoscope) was used in evaluating the choroidal lesion in question and that some times the scotoma could not be found when such an ophthalmoscopic examination did not precede the visual field study. Nevi exceeding the thickness of the nor mal choroid expand mainly toward the ret-
VOL. 62, NO. 5
VISUAL FIELDS IN CHOROIDAL NEVUS
ina. Thus the retina overlying the nevus is moved to a different level and "out of focus" and is therefore rendered relatively hyperopic in comparison with the rest of the retina. This probably is negligible while testing with large targets but must be recog nizable with minute targets, particularly in the central area of the nevus, where the ele vation is highest. Accordingly these scotomas are relative in that they can be elicited only with small targets 5 and are smaller than would be expected from the size of the lesion.8 We do not feel that the two mechanisms just mentioned have any bearing on the visual field defect in our particular case. Our report illustrates that a benign pigmented nevus of the choroid does have the potential to cause pronounced retinal degen eration and thus produce not only a relative but even an absolute scotoma of the visual field. We can only speculate on how these changes develop. The choriocapillaris, al though narrowed, is not obliterated, and one therefore must postulate a competition for nutritional material between the nevus cells and the sensory retina. The occurrence of relative scotomas in association with choroidal nevi is well docu mented, although several authors9"13 have not observed such visual field defects, but almost all ophthalmologists doubt that abso lute scotomas can be attributed to benign melanotic lesions. The demonstration of an absolute scotoma corresponding to a lesion suspected of being either a nevus or a ma lignant melanoma is generally interpreted as reliable evidence that the lesion in question is malignant and that enucleation is jus tified. The present case, we believe, indi cates that exceptions to this rule may be en countered and that additional biologic evi dence of malignancy (for example, progres sive growth) should be obtained before a
917
small suspicious tumor is treated by enuclea tion. SUMMARY
A case of nevus of the choroid with corre sponding absolute visual field defect is re ported. The histopathologic characteristics of the tumor and the degenerative changes in the retina overlying it are described. Thus, the mechanism for the production of an absolute scotoma is illustrated. Armed Forces Institute of Pathology (20305) REFERENCES
1. Bettman, J. W., and Fellows, V.: Differential diagnosis of dark lesions of posterior fundus. Am. J. Ophth. 41:97S, 1956. 2. Hogan, M. J.: Clinical aspects, management and prognosis of melanomas of the uvea and optic nerve. In Boniuk, M. (ed.) : Ocular and Adnexal Tumors. St. Louis, Mosby, 1964, pp. 203-302. 3. Katzin, H. M.: Cited by Hogan.' 4. Reese, A. B.: Tumors of the Eye. New York, Hoeber, 1951. 5. Tamler, E., and Maumenee, A. E.: Clinical study of choroidal nevi. Arch. Ophth. 62:196, 1959. 6. Naumann, G., Yanoff, M., and Zimmerman, L. E.: Histogenesis of malignant melanoma of the uvea: I. Histopathologic characteristics of nevi of the choroid and ciliary body. Arch. Ophth., in press. 7. Kruse, W., and Utermann, D.: Beitrag zur Erkennung refraktionsbedingter Skotome. Klin. Mbl. Augen. 143 :247, 1963. 8. Reese, A. B., and Jones, I. S.: Differential diagnosis of malignant melanoma of choroid. Arch. Ophth. 58:477, 1957. 9. Albers, E. C.: Benign melanomas of choroid and their malignant transformation. Am J. Ophth. 23 :779, 1940. 10. Ballantyne, A. J., and Michaelson, I. C.: Textbook of the Fundus of the Eye. Baltimore, Williams & Wilkins, 1962. 11. Blodi, F.: Melanoma. In Sorsby, A.(ed.) : Modern Ophthalmology. Washington, Butterworth, 1964, p. 344-380. 12. Moore, R. F.: Four cases of melanoma of the choroid, with a pathological examination in one case; and one case of unusual chronicity, after dissemination of a melanotic sarcoma had occurred. Roy. Lond. Ophth. Rep. 19:411, 1914. 13. Stallard, H. B.: Diseases of the choroid. In Berens, C.(ed.): The Eye and Its Diseases. Phil adelphia, Saunders, ed. 2, 1949.