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Retinal Pigment Epithelial Tears
Retinal Pigment Epithelial Tears Patterns and Prognosis JULIA HALLER YEO, MD, SERGIU MARCUS, MD, PhD, ROBERT P. MURPHY, MD
Abstract: Increasing experience with the diagnosis of retinal pigment epithelial (RPE) tears has led to expanded recognition and understanding of this clinical entity. The authors report 18 RPE tears followed for an average of 28 months; 16 were associated with age-related macular degeneration and 2 with presumed ocular histoplasmosis syndrome. Retinal pigment epithelial dehiscences fell into four categories: nine spontaneous tears associated with choroidal neovascularization, one tear associated with an RPE detachment without choroidal neovascularization, four iatrogenic tears occurring at krypton treatment of choroidal neovascularization, and four iatrogenic tears developing weeks to months after laser treatment of choroidal neovascularization . Eight patients had a final visual acuity of 20/100 or better, four were 20/200, and six were 20/400 or worse. Photocoagulation, particularly with the use of krypton red laser, may be modified on the basis of possible RPE tear formation. Heightened awareness of the possibility of inducing pigment epithelial rips should improve diagnosis and management of these cases. [Key words: age-related macular degeneration, choroidal neovascularization, krypton red laser, laser photocoagulation , presumed ocular histoplasmosis syndrome, retinal pigment epithelial dehiscence, retinal pigment epithelial detachment, retinal pigment epithelial rip, retinal pigment epithelial tear, retinal pigment epithelium .] Ophthalmology
95:8-13,1988
. Since the initial recognition of tears of the retinal pigment epithelium (RPE) by Hoskin et all in 1981, our understanding of their clinical, pathologic, and prognostic implications has greatly expanded. 2- 12 These tears are characterized by a dehiscence and subsequent retraction of a segment of RPE with its subjacent basement membrane from the remaining outer portion of Bruch's membrane_ Retinal pigment epithelial tears are generally seen in association with age-related macular degeneration, especially after laser photocoagulation of choroidal neovascularization_ 4,5,9 Isolated cases have From The Wilmer Institute, The Johns Hopkins Medical Institutions, Baltimore. Presented at the American Academy of Ophthalmology Annual Meeting, New Orleans, November 1986. Reprint requests to Julia H. Yeo, MD, Wilmer 300, The Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21205.
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been reported with retinal detachments and chorioretinal scarring. to Tears appear clinically as a rolled flap of pigment epithelium adjacent to a hypopigmented area of denuded Bruch's membrane. On fluorescein angiography, there is early hyperfluorescence in the area of bared Bruch's membrane; pronounced hypofluorescence may be apparent in the area of the retracted RPE. Gass l3 has speculated that all tears of the RPE are associated with a choroidal neovascular process. Recent histopathologic studies of two cases,14 however, indicate that although the dehiscences may occur because of the tangential forces exerted by a neovascular membrane, they may also be associated with RPE atrophy and ripping in association with an RPE detachment. Previously reported series of RPE tears have featured a generally poor visual prognosis, with a typical clinical course of progression to a fibrous disciform scar or a large atrophic lesion. Decker et al 4 found that 26 of 28 eyes in their series were left with vision less than 20/200.
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Fig 1. Case 1. Top left, redfree photograph of the left eye of a 66-year-old white woman with acute visual loss. A serous pigment epithelial detachment is evident, surrounded by lipid exudates indicative of choroidal neovascularization (large arrows). The linear contour at the superonasal border of the RPE detachment (small arrows) defines the sharply demarcated pigment epithelial tear. Top right, a mid-transit fluorescein angiogram demonstrates early hyperfluorescence corresponding to the denuded area of choriocapillaris exposed by the rip (arrows). Hypofluorescence temporal to this delineates the rolled flap of retracted pigment epithelium. Bottom, a late fluorescein frame shows continued uniform hyperfluorescence without late leakage in the area of exposed choriocapillaris. Hypofluorescence in a corrugated pattern temporal to the sharply demarcated edge of the tear (small arrows), defines the retracted pigment epithelium. Hyperfluorescent regions superotemporally and inferotemporally (large arrows) denote late uneven filling of the pigment epithelial detachment, another sign of occult neovascularization.
Hoskin et aI' reported that only 8 of 44 eyes with nonfoveal tears preserved "relatively good" central acuity. We report a series of 18 RPE tears diagnosed at the Wilmer Institute and followed long-term, which adds to our knowledge of this disease process.
MATERIALS AND METHODS Eighteen cases of RPE tears were collected from patients seen in the Retinovascular Center of the Wilmer Institute. Nine cases were identified prospectively and nine found retrospectively on follow-up of patients followed with other diagnoses. Five patients were found to have RPE tears at initial evaluation. The remaining 13 rips developed as the patients were followed. Documentation and follow-up on all patients included complete examination with visual acuity testing and fundus biomicroscopy in combination with sequential stereo fundus photography and fluorescein angiography.
RESULTS Eighteen patients were identified with RPE tears. In 16 patients, the tears were associated with features of age-related macular degeneration, specifically drusen variably accompanied by RPE detachment, geographic
RPE atrophy, and/or choroidal neovascularization. In two patients, the rips occurred in eyes with presumed ocular histoplasmosis syndrome. The two patients with this syndrome were 25 years of age. The ages of the remaining 16 patients ranged from 58 to 86 years (average, 72 years). Ten patients were women and eight were men. The right eye was involved in 12 cases, the left in 6. Follow-up ranged from 8 months to 9 years and 10 months (average, 28 months offollow-up). PATTERNS OF RETINAL PIGMENT EPITHELIAL TEARS
All cases fell into the following four identifiable categories. (1) Spontaneous RPE tears associated with a choroidal neovascular membrane. Nine cases were identified. One such case (case 1) was that of a 66-year-old white woman followed for some time with age-related macular degeneration and a disciform scar in the right eye, who presented with a recent decrease in visual acuity in the left eye. On examination, she had a serous pigment epithelial detachment associated with a large RPE tear superonasal to the fovea. Lipid deposits ringing the pigment epithelial detachment and late uneven filling of the detachment on fluorescein angiography were consistent with occult choroidal neovascularization (Fig 1). The fluorescein angiogram showed a linear contour of 9
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early even hyperfluorescence corresponding to the denuded area of the choriocapillaris. This hyperfluorescence persisted in the late frames without leakage to suggest a localized neovascular membrane. Hypofluorescence was seen temporal to the sharply demarcated edge of the RPE tear (small arrows, Fig 1, bottom), defining the retracted, rolled edge of the pigment epithelium. The patient's visual acuity remained poor (20/400) 2 years later, consistent with a rip toward the fovea. (2) Spontaneous RPE tears associated with pigment epithelial detachment without identifiable choroidal neovascularization. One case was identified. This 63year-old white woman (case 2) was followed with drusen and pigmentary changes in both eyes and a visual acuity of20/25 in the left. She presented with a 4-day history of decreased visual acuity in the left eye and was found to have a small serous pigment epithelial detachment with slight hyperpigmentation on the nasal border, surrounded temporally and inferiorly by confluent soft drusen (Fig 2, top left). There was no neovascularization suspected by ophthalmoscopy or angiography. Two weeks later the patient complained of further acuity loss in the left eye, and an acute dehiscence of the pigment epithelium was seen in the area of the previous serous detachment of the pigment epithelium (Fig 2, second row left). The fluorescein angiogram showed even hyperfluorescence in the area of the denuded choriocapillaris, with hypofluorescence below corresponding to the retracted RPE flap (Fig 2, third row left). Two years later (Fig 2, bottom left), vision remained 20/40, consistent with an extrafoveal rip without development of neovascularization. (3) Iatrogenic RPE tears occurring at the time of laser treatment of choroidal neovascularization. Four cases were identified. In one such case (case 3), a 65year-old woman was followed after treatment of an extrafoveal choroidal neovascular membrane in the right eye. A recurrence at the superotemporal edge of the previous treatment developed. During treatment of the recurrent membrane with krypton red laser, retraction of the subretinal fibrovascular tissue toward the treatment area with RPE tearing was observed. Two weeks later, the area of the rip had extended crescenterically (Fig 3). Consistent with the extrafoveal location of the RPE dehiscence, visual acuity was 20/30 17 months later. This rip is typical of those which we found associated with laser photocoagulation, in that it occurred with intense treatment. Intratreatment recognition of retraction of the subretinal fibrovascular tissue with the RPE was important because this area did not require photocoagulation. Awareness of the rip's occurrence was also significant because results of the posttreatment fluorescein angiography showed hyperfiuorescence in the exposed area of choriocapillaris (Fig 3, third row right), which could have been easily mistaken for a recurrent membrane, and erroneously treated. (4) Iatrogenic RPE tears occurring weeks to months after laser treatment of choroidal neovascularization. Four cases were identified. In three of the four cases, 10
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pigment epithelial tearing was identified within 3 weeks of treatment. In the remaining case, a tear clearly developed 15 months after retreatment with krypton laser. In one such case (case 4), a 75-year-old man was treated with krypton laser for an extrafoveal recurrence of a choroidal neovascular membrane (Fig 4, top left). Without any additional treatment, he presented 3 weeks later with visual loss in the left eye, and an RPE rip was diagnosed superotemporal to the previously treated area (Fig 4, second row left). Results of fluorescein angiography showed the linear contour of an RPE rip with even hyperfluorescence in the area of exposed choriocapillaris (Fig 4, third row left). Prominent rugate folds (Fig 4, third row left) were apparent in the retracted flap of RPE. This rip with its early hyperfluorescence on fluorescein angiography (Figs 4, third row and bottom left) could have been mistaken for recurrence of a neovascular membrane and unnecessarily treated. In all eight cases of laser treatment-associated RPE tears, krypton red laser was used. In six of these eyes, ripping occurred at photocoagulation of recurrent choroidal neovascularization. In the remaining two cases, tears developed at initial treatment of choroidal neovascularization. Treatment parameters included spot size of 200 ~m and duration of at least 0.5 seconds, with variable intensity levels used to produce a white burn. FINAL VISUAL ACUITY
Eight patients achieved a final visual acuity of 20/ 100 or better. Four patients had final vision of 20/200 and six had 20/400 or worse (Table 1). Of the eight eyes with 20/100 or better vision, two were 20/30, two were 20/40, two were 20/60, and two were 20/100. Both patients with RPE tear-associated presumed ocular histoplasmosis syndrome had 20/100 vision at last examination. The eight eyes with iatrogenic tears were left with visual acuities of 20/30 (1 eye), 20/60 (1 eye), 20/100 (2 eyes), 20/200 (1 eye), and 20/400 or worse (3 eyes). Tears which were extrafoveal or which involved RPE retraction away from the macula resulted in better vision than tears involving subfoveal tissue.
CONCLUSION Several mechanisms appear to be important in RPEtear pathogenesis. 7,13,14 Weakening of intercellular connections between epithelial cells because of a chronic RPE detachment combined with hydrostatic pressure from serous sub-RPE fluid may cause a delamination of Bruch's membrane, with subsequent dehiscence of the RPE with its basement membrane. The torn edge of the RPE flap retracts, rolling into characteristic folds. The denuded outer portion of Bruch's membrane with subjacent choriocapillaris is then exposed, yielding the typical clinical and fluorescein angiographic appearance of an RPE tear.
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Fig 2. Case 2. Top left. left eye of a 63-year-old woman with a 4-day history of decreased vision. Notice the soft confluent drusen in the macular area, and a small pigment epithelial detachment with mild hyperpigmentation in the center. Second row left. 2 weeks later, further acute decrease in visual acuity developed. The area of the pigment epithelial detachment showed a well-demarcated ovoid area of hypopigmentation with slight hyperpigmentation nasally and inferiorly. Contact lens biomicroscopy confirmed a pigment epithelial rip without evidence of choroidal neovascularization. Third row left. midtransit fluorescein angiogram corresponding to the color photograph in Figure 2, second row left. Hyperfluorescence in the crescentic area of denuded choriocapillaris delineates the RPE tear (arrow), with a hypofluorescent area of rolled pigment epithelium below. BOllom. 2 years later, there is still no evidence of choroidal neovascularization. Central hypopigmentation corresponds to the pigment epithelial rip which now resembles an area of geographic atrophy. Notice the marked change in the pattern of drusen, with loss of confluence as compared with Figure 2, second row left. Fig 3. Case 3. Top and second row right. a recurrent choroidal neovascular membrane developed in this 65-year-old woman after previous laser photocoagulation. In the color photograph, the large area of pigment epithelial atrophy (yellow in the schematic diagram) corresponds to the previously treated extrafoveal membrane. Photocoagulation to a recurrent membrane is seen on the foveal side of the previous laser scar (green in the diagram). During retreatment, retraction of the fibrovascular membrane with RPE tearing was observed toward the treated area (hatched blue in the diagram). One week later, the area of the pigment epithelial dehiscence had extended inferonasaIly to form a hypopigmented crescent (blue in the diagram). Third row right. a late frame of the fluorescein angiogram demonstrates late uniform hyperfluorescence of the exposed choriocapillaris (arrows).
In RPE tears associated with choroidal neovascularization, the new vessel membrane insinuates itself into Bruch's membrane, separating the RPE with its basement membrane from the subjacent outer portion of Bruch's membrane. By exerting tangential shearing forces, this may eventuate in an RPE rip. Laser energy may initiate or exacerbate this tractional force. The folded margin of the tear rolls back to expose Bruch's membrane and the choriocapillaris (Fig 6).
Acute thermal laser energy delivered to the RPE and choroid with subsequent focal tissue shrinkage can cause RPE tearing. More remotely, later fibrous tissue ingrowth with chronic tangential traction may also predispose to RPE tears. Increasing awareness of the phenomenon of RPE dehiscence has enabled us to identify more patients in whom this condition exists. In particular, we recognize intratreatment and posttreatment tearing of the pigment
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Fig 4. Case 4. Top left. this 75-year-old man was treated with krypton red laser for a recurrent choroidal neovascular membrane. Notice the even pigmentation of the RPE temporal to the laser site . Second row left. 2 weeks later, the patient noted a decrease in visual acuity. Superotemporal to the previous laser scars an RPE tear was seen, with a typical linear zone of dehiscence. Third row and bottom left. on fluorescein angiography, the linear edge of the hyperfiuorescent RPE tear (small arrows) (blue in schematic diagram) is seen superotemporal to the laser scars (yellow and green in diagram). Prominent rugate folding (f) delineates the retracted flap of pigment epithelium. Fig 5. Top right. diagram of RPE tear associated with pigment epithelial detachment. Weakening of intercellular connections between pigment epithelial cells causes dehiscence of the RPE with its basement membrane at the edge of the detachment. Fig 6. Second row right. diagram illustrating an RPE tear in association with a choroidal neovascular membrane. The membrane insinuates itself between the RPE with its basement membrane and the subjacent outer portion of Bruch's membrane, exerting tangential tractional forces which produce a rip.
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epithelium occurring in association with laser photocoagulation of choroidal new vessel membranes. There are at least four patterns into which RPE tears fall: (1) spontaneous tears associated with choroidal neovascularization; (2) spontaneous tears associated with pigment epithelial detachments but without ophthalmoscopic or angiographic evidence of choroidal neovascularization; (3) iatrogenic tears that occur at the time of photocoagulation of choroidal neovascularization; and 12
(4) iatrogenic tears that develop weeks to months after laser treatment. We are further able to identify tears in which the visual prognosis is reasonably good long term. In 8 of 18 eyes (44%), final visual acuity was 20/100 or better. In four eyes, visual acuity was 20/40 or better. Extrafoveal rips are consistent with good acuity. Conversely, rips that involve the fovea or progress toward the fovea may be associated with a poorer visual prognosis. Of course
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Table 1. Long-term Visual Acuity Results in Eyes with RPE Tears
RPE
=
Acuity
No. of Patients
20/30 20/40 20/60 20/100 20/200 20/400
2 2 2 2
4
6
retinal pigment epithelium.
visual prognosis ultimately depends on the integrity of the foveal photoreceptors and reflects the severity of the underlying disease process. An interesting subgroup of RPE tears in this series is that associated with laser photocoagulation because these iatrogenic tears are significant to physicians treating retinal lesions. All such tears developed in eyes treated with krypton red photocoagulation. This suggests a possible predilection for pigment epithelial tearing with the krypton laser which is absorbed by the melanocytes of the pigment epithelium and choroid. The apparent association may, however, at least partially reflect the preponderant use of krypton laser in the macular area. Retinal pigment epithelial tears have been reported after argon laser photocoagulation as well. 2 Retraction of the fibrovascular membrane with RPE tearing during application of laser photocoagulation occurred at the heavy thermal energy levels used to produce a standard white burn. It may be wise, therefore, to moderate treatment initially with careful observation for membrane and RPE retraction, and then proceed to heavier treatment later in the course of photocoagulation. This is especially true with a hypopigmented fibrovascular membrane, where the energy necessary to produce a white retinal burn may inadvertently result in delivery oflarge amounts of thermal energy to the RPE, as Gass has suggested. 5 Retinal pigment epithelial tears may occur at an edge of the neovascular membrane remote from the immediate area of treatment. It is therefore important to be aware at all times of the full extent of the membrane so as to monitor carefully for retraction. Appropriate modification of treatment may be necessary. In four of our cases, rips occurred at some point after laser treatment of a new vessel membrane. Since the
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fluorescein angiogram in such cases shows hyperfluorescence at the edge of previous treatment, these rips may be mistaken for recurrent membranes. Retreatment of a mistakenly diagnosed recurrent membrane may worsen the visual acuity by inciting further RPE ripping or damaging macular tissue. A rip itself does not warrant retreatment. Retinal pigment epithelial tears occur in association with choroidal neovascularization as well as with pigment epithelial detachments with or without neovascularization. They may develop during or after laser photocoagulation. Awareness of the potential for RPE tear development as well as its prognostic significance is important in the management of macular disease.
REFERENCES 1. Hoskin A, Bird AC, Sehmi K. Tears of detached retinal pigment epithelium. Br J Ophthalmol1981; 65:417-22. 2. Cantrill HL, Ramsay RC, Knobloch WHo Rips in the pigment epithe· lium. Arch Ophthalmol1983; 101 :1074-9. 3. Coscas G, Quentel G, Pinon F, Soubrane G. Dechirure spontanee de I'epithelium pigmentaire dans la region maculaire. Bull Soc Ophtalmol Fr 1982; 82:815-20. 4. Decker WL, Sanbom GE, Ridley M, et al. Retinal pigment epithelial tears. Ophthalmology 1983; 90:507-12. 5. Gass JDM. Retinal pigment epithelial rip during krypton red laser photocoagulation. Am J Ophthalmol1984; 98:700-6. 6. Green SN, Yarian D. Acute tear of the retinal pigment epithelium. Retina 1983; 3:16-20. 7. Krishan NR, Chandra SR, Stevens TS. Diagnosis and pathogenesis of retinal pigment epithelial tears. Am J Ophthalmol 1985; 100:698707. 8. Laatikainen L. Rupture of retinal pigment epithelial detachment in senile macular disease. Acta Ophthalmol 1983; 61: 1-8. 9. Murphy RP, Yeo JH, Green WR, Patz A. Dehiscences of the pigment epithelium. Trans Am Ophthalmol Soc 1985; 83:63-81. 10. Swanson DE, Kalina RE, Guzak SV. Tears of the retinal pigment epithelium: occurrence in retinal detachments and a chorioretinal scar. Retina 1984; 4:115-8. 11. Traboulsi EI, Jalkh AE. Retinal pigment epithelium tear as a cause of vitreous hemorrhage. Ann Ophthalmol1985; 17:228-35. 12. Tutein Nolthenius PA, Deutman AF. Rips of the retinal pigment epithelium. Int Ophthalmol1985; 8:19-23. 13. Gass JDM. Pathogenesis of tears of the retinal pigment epithelium. Br J Ophthalmol 68:1984; 513-9. 14. Green WR, McDonnell PJ, Yeo JH. Pathologic features of senile macular degeneration. Ophthalmology 1985; 92:615-27.
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Abstract: Increasing experience with the diagnosis of retinal pigment epithelial (RPE) tears has led to expanded recognition and understanding of this clinical entity. The authors report 18 RPE tears followed for an average of 28 months; 16 were associated with age-related macular degeneration and 2 with presumed ocular histoplasmosis syndrome. Retinal pigment epithelial dehiscences fell into four categories: nine spontaneous tears associated with choroidal neovascularization, one tear associated with an RPE detachment without choroidal neovascularization, four iatrogenic tears occurring at krypton treatment of choroidal neovascularization, and four iatrogenic tears developing weeks to months after laser treatment of choroidal neovascularization . Eight patients had a final visual acuity of 20/100 or better, four were 20/200, and six were 20/400 or worse. Photocoagulation, particularly with the use of krypton red laser, may be modified on the basis of possible RPE tear formation. Heightened awareness of the possibility of inducing pigment epithelial rips should improve diagnosis and management of these cases. [Key words: age-related macular degeneration, choroidal neovascularization, krypton red laser, laser photocoagulation , presumed ocular histoplasmosis syndrome, retinal pigment epithelial dehiscence, retinal pigment epithelial detachment, retinal pigment epithelial rip, retinal pigment epithelial tear, retinal pigment epithelium .] Ophthalmology
95:8-13,1988
. Since the initial recognition of tears of the retinal pigment epithelium (RPE) by Hoskin et all in 1981, our understanding of their clinical, pathologic, and prognostic implications has greatly expanded. 2- 12 These tears are characterized by a dehiscence and subsequent retraction of a segment of RPE with its subjacent basement membrane from the remaining outer portion of Bruch's membrane_ Retinal pigment epithelial tears are generally seen in association with age-related macular degeneration, especially after laser photocoagulation of choroidal neovascularization_ 4,5,9 Isolated cases have From The Wilmer Institute, The Johns Hopkins Medical Institutions, Baltimore. Presented at the American Academy of Ophthalmology Annual Meeting, New Orleans, November 1986. Reprint requests to Julia H. Yeo, MD, Wilmer 300, The Johns Hopkins Hospital, 600 N. Wolfe Street, Baltimore, MD 21205.
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been reported with retinal detachments and chorioretinal scarring. to Tears appear clinically as a rolled flap of pigment epithelium adjacent to a hypopigmented area of denuded Bruch's membrane. On fluorescein angiography, there is early hyperfluorescence in the area of bared Bruch's membrane; pronounced hypofluorescence may be apparent in the area of the retracted RPE. Gass l3 has speculated that all tears of the RPE are associated with a choroidal neovascular process. Recent histopathologic studies of two cases,14 however, indicate that although the dehiscences may occur because of the tangential forces exerted by a neovascular membrane, they may also be associated with RPE atrophy and ripping in association with an RPE detachment. Previously reported series of RPE tears have featured a generally poor visual prognosis, with a typical clinical course of progression to a fibrous disciform scar or a large atrophic lesion. Decker et al 4 found that 26 of 28 eyes in their series were left with vision less than 20/200.
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Fig 1. Case 1. Top left, redfree photograph of the left eye of a 66-year-old white woman with acute visual loss. A serous pigment epithelial detachment is evident, surrounded by lipid exudates indicative of choroidal neovascularization (large arrows). The linear contour at the superonasal border of the RPE detachment (small arrows) defines the sharply demarcated pigment epithelial tear. Top right, a mid-transit fluorescein angiogram demonstrates early hyperfluorescence corresponding to the denuded area of choriocapillaris exposed by the rip (arrows). Hypofluorescence temporal to this delineates the rolled flap of retracted pigment epithelium. Bottom, a late fluorescein frame shows continued uniform hyperfluorescence without late leakage in the area of exposed choriocapillaris. Hypofluorescence in a corrugated pattern temporal to the sharply demarcated edge of the tear (small arrows), defines the retracted pigment epithelium. Hyperfluorescent regions superotemporally and inferotemporally (large arrows) denote late uneven filling of the pigment epithelial detachment, another sign of occult neovascularization.
Hoskin et aI' reported that only 8 of 44 eyes with nonfoveal tears preserved "relatively good" central acuity. We report a series of 18 RPE tears diagnosed at the Wilmer Institute and followed long-term, which adds to our knowledge of this disease process.
MATERIALS AND METHODS Eighteen cases of RPE tears were collected from patients seen in the Retinovascular Center of the Wilmer Institute. Nine cases were identified prospectively and nine found retrospectively on follow-up of patients followed with other diagnoses. Five patients were found to have RPE tears at initial evaluation. The remaining 13 rips developed as the patients were followed. Documentation and follow-up on all patients included complete examination with visual acuity testing and fundus biomicroscopy in combination with sequential stereo fundus photography and fluorescein angiography.
RESULTS Eighteen patients were identified with RPE tears. In 16 patients, the tears were associated with features of age-related macular degeneration, specifically drusen variably accompanied by RPE detachment, geographic
RPE atrophy, and/or choroidal neovascularization. In two patients, the rips occurred in eyes with presumed ocular histoplasmosis syndrome. The two patients with this syndrome were 25 years of age. The ages of the remaining 16 patients ranged from 58 to 86 years (average, 72 years). Ten patients were women and eight were men. The right eye was involved in 12 cases, the left in 6. Follow-up ranged from 8 months to 9 years and 10 months (average, 28 months offollow-up). PATTERNS OF RETINAL PIGMENT EPITHELIAL TEARS
All cases fell into the following four identifiable categories. (1) Spontaneous RPE tears associated with a choroidal neovascular membrane. Nine cases were identified. One such case (case 1) was that of a 66-year-old white woman followed for some time with age-related macular degeneration and a disciform scar in the right eye, who presented with a recent decrease in visual acuity in the left eye. On examination, she had a serous pigment epithelial detachment associated with a large RPE tear superonasal to the fovea. Lipid deposits ringing the pigment epithelial detachment and late uneven filling of the detachment on fluorescein angiography were consistent with occult choroidal neovascularization (Fig 1). The fluorescein angiogram showed a linear contour of 9
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early even hyperfluorescence corresponding to the denuded area of the choriocapillaris. This hyperfluorescence persisted in the late frames without leakage to suggest a localized neovascular membrane. Hypofluorescence was seen temporal to the sharply demarcated edge of the RPE tear (small arrows, Fig 1, bottom), defining the retracted, rolled edge of the pigment epithelium. The patient's visual acuity remained poor (20/400) 2 years later, consistent with a rip toward the fovea. (2) Spontaneous RPE tears associated with pigment epithelial detachment without identifiable choroidal neovascularization. One case was identified. This 63year-old white woman (case 2) was followed with drusen and pigmentary changes in both eyes and a visual acuity of20/25 in the left. She presented with a 4-day history of decreased visual acuity in the left eye and was found to have a small serous pigment epithelial detachment with slight hyperpigmentation on the nasal border, surrounded temporally and inferiorly by confluent soft drusen (Fig 2, top left). There was no neovascularization suspected by ophthalmoscopy or angiography. Two weeks later the patient complained of further acuity loss in the left eye, and an acute dehiscence of the pigment epithelium was seen in the area of the previous serous detachment of the pigment epithelium (Fig 2, second row left). The fluorescein angiogram showed even hyperfluorescence in the area of the denuded choriocapillaris, with hypofluorescence below corresponding to the retracted RPE flap (Fig 2, third row left). Two years later (Fig 2, bottom left), vision remained 20/40, consistent with an extrafoveal rip without development of neovascularization. (3) Iatrogenic RPE tears occurring at the time of laser treatment of choroidal neovascularization. Four cases were identified. In one such case (case 3), a 65year-old woman was followed after treatment of an extrafoveal choroidal neovascular membrane in the right eye. A recurrence at the superotemporal edge of the previous treatment developed. During treatment of the recurrent membrane with krypton red laser, retraction of the subretinal fibrovascular tissue toward the treatment area with RPE tearing was observed. Two weeks later, the area of the rip had extended crescenterically (Fig 3). Consistent with the extrafoveal location of the RPE dehiscence, visual acuity was 20/30 17 months later. This rip is typical of those which we found associated with laser photocoagulation, in that it occurred with intense treatment. Intratreatment recognition of retraction of the subretinal fibrovascular tissue with the RPE was important because this area did not require photocoagulation. Awareness of the rip's occurrence was also significant because results of the posttreatment fluorescein angiography showed hyperfiuorescence in the exposed area of choriocapillaris (Fig 3, third row right), which could have been easily mistaken for a recurrent membrane, and erroneously treated. (4) Iatrogenic RPE tears occurring weeks to months after laser treatment of choroidal neovascularization. Four cases were identified. In three of the four cases, 10
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pigment epithelial tearing was identified within 3 weeks of treatment. In the remaining case, a tear clearly developed 15 months after retreatment with krypton laser. In one such case (case 4), a 75-year-old man was treated with krypton laser for an extrafoveal recurrence of a choroidal neovascular membrane (Fig 4, top left). Without any additional treatment, he presented 3 weeks later with visual loss in the left eye, and an RPE rip was diagnosed superotemporal to the previously treated area (Fig 4, second row left). Results of fluorescein angiography showed the linear contour of an RPE rip with even hyperfluorescence in the area of exposed choriocapillaris (Fig 4, third row left). Prominent rugate folds (Fig 4, third row left) were apparent in the retracted flap of RPE. This rip with its early hyperfluorescence on fluorescein angiography (Figs 4, third row and bottom left) could have been mistaken for recurrence of a neovascular membrane and unnecessarily treated. In all eight cases of laser treatment-associated RPE tears, krypton red laser was used. In six of these eyes, ripping occurred at photocoagulation of recurrent choroidal neovascularization. In the remaining two cases, tears developed at initial treatment of choroidal neovascularization. Treatment parameters included spot size of 200 ~m and duration of at least 0.5 seconds, with variable intensity levels used to produce a white burn. FINAL VISUAL ACUITY
Eight patients achieved a final visual acuity of 20/ 100 or better. Four patients had final vision of 20/200 and six had 20/400 or worse (Table 1). Of the eight eyes with 20/100 or better vision, two were 20/30, two were 20/40, two were 20/60, and two were 20/100. Both patients with RPE tear-associated presumed ocular histoplasmosis syndrome had 20/100 vision at last examination. The eight eyes with iatrogenic tears were left with visual acuities of 20/30 (1 eye), 20/60 (1 eye), 20/100 (2 eyes), 20/200 (1 eye), and 20/400 or worse (3 eyes). Tears which were extrafoveal or which involved RPE retraction away from the macula resulted in better vision than tears involving subfoveal tissue.
CONCLUSION Several mechanisms appear to be important in RPEtear pathogenesis. 7,13,14 Weakening of intercellular connections between epithelial cells because of a chronic RPE detachment combined with hydrostatic pressure from serous sub-RPE fluid may cause a delamination of Bruch's membrane, with subsequent dehiscence of the RPE with its basement membrane. The torn edge of the RPE flap retracts, rolling into characteristic folds. The denuded outer portion of Bruch's membrane with subjacent choriocapillaris is then exposed, yielding the typical clinical and fluorescein angiographic appearance of an RPE tear.
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Fig 2. Case 2. Top left. left eye of a 63-year-old woman with a 4-day history of decreased vision. Notice the soft confluent drusen in the macular area, and a small pigment epithelial detachment with mild hyperpigmentation in the center. Second row left. 2 weeks later, further acute decrease in visual acuity developed. The area of the pigment epithelial detachment showed a well-demarcated ovoid area of hypopigmentation with slight hyperpigmentation nasally and inferiorly. Contact lens biomicroscopy confirmed a pigment epithelial rip without evidence of choroidal neovascularization. Third row left. midtransit fluorescein angiogram corresponding to the color photograph in Figure 2, second row left. Hyperfluorescence in the crescentic area of denuded choriocapillaris delineates the RPE tear (arrow), with a hypofluorescent area of rolled pigment epithelium below. BOllom. 2 years later, there is still no evidence of choroidal neovascularization. Central hypopigmentation corresponds to the pigment epithelial rip which now resembles an area of geographic atrophy. Notice the marked change in the pattern of drusen, with loss of confluence as compared with Figure 2, second row left. Fig 3. Case 3. Top and second row right. a recurrent choroidal neovascular membrane developed in this 65-year-old woman after previous laser photocoagulation. In the color photograph, the large area of pigment epithelial atrophy (yellow in the schematic diagram) corresponds to the previously treated extrafoveal membrane. Photocoagulation to a recurrent membrane is seen on the foveal side of the previous laser scar (green in the diagram). During retreatment, retraction of the fibrovascular membrane with RPE tearing was observed toward the treated area (hatched blue in the diagram). One week later, the area of the pigment epithelial dehiscence had extended inferonasaIly to form a hypopigmented crescent (blue in the diagram). Third row right. a late frame of the fluorescein angiogram demonstrates late uniform hyperfluorescence of the exposed choriocapillaris (arrows).
In RPE tears associated with choroidal neovascularization, the new vessel membrane insinuates itself into Bruch's membrane, separating the RPE with its basement membrane from the subjacent outer portion of Bruch's membrane. By exerting tangential shearing forces, this may eventuate in an RPE rip. Laser energy may initiate or exacerbate this tractional force. The folded margin of the tear rolls back to expose Bruch's membrane and the choriocapillaris (Fig 6).
Acute thermal laser energy delivered to the RPE and choroid with subsequent focal tissue shrinkage can cause RPE tearing. More remotely, later fibrous tissue ingrowth with chronic tangential traction may also predispose to RPE tears. Increasing awareness of the phenomenon of RPE dehiscence has enabled us to identify more patients in whom this condition exists. In particular, we recognize intratreatment and posttreatment tearing of the pigment
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Fig 4. Case 4. Top left. this 75-year-old man was treated with krypton red laser for a recurrent choroidal neovascular membrane. Notice the even pigmentation of the RPE temporal to the laser site . Second row left. 2 weeks later, the patient noted a decrease in visual acuity. Superotemporal to the previous laser scars an RPE tear was seen, with a typical linear zone of dehiscence. Third row and bottom left. on fluorescein angiography, the linear edge of the hyperfiuorescent RPE tear (small arrows) (blue in schematic diagram) is seen superotemporal to the laser scars (yellow and green in diagram). Prominent rugate folding (f) delineates the retracted flap of pigment epithelium. Fig 5. Top right. diagram of RPE tear associated with pigment epithelial detachment. Weakening of intercellular connections between pigment epithelial cells causes dehiscence of the RPE with its basement membrane at the edge of the detachment. Fig 6. Second row right. diagram illustrating an RPE tear in association with a choroidal neovascular membrane. The membrane insinuates itself between the RPE with its basement membrane and the subjacent outer portion of Bruch's membrane, exerting tangential tractional forces which produce a rip.
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ill- '" rID"'........ ,,;......
epithelium occurring in association with laser photocoagulation of choroidal new vessel membranes. There are at least four patterns into which RPE tears fall: (1) spontaneous tears associated with choroidal neovascularization; (2) spontaneous tears associated with pigment epithelial detachments but without ophthalmoscopic or angiographic evidence of choroidal neovascularization; (3) iatrogenic tears that occur at the time of photocoagulation of choroidal neovascularization; and 12
(4) iatrogenic tears that develop weeks to months after laser treatment. We are further able to identify tears in which the visual prognosis is reasonably good long term. In 8 of 18 eyes (44%), final visual acuity was 20/100 or better. In four eyes, visual acuity was 20/40 or better. Extrafoveal rips are consistent with good acuity. Conversely, rips that involve the fovea or progress toward the fovea may be associated with a poorer visual prognosis. Of course
YEO et al
Table 1. Long-term Visual Acuity Results in Eyes with RPE Tears
RPE
=
Acuity
No. of Patients
20/30 20/40 20/60 20/100 20/200 20/400
2 2 2 2
4
6
retinal pigment epithelium.
visual prognosis ultimately depends on the integrity of the foveal photoreceptors and reflects the severity of the underlying disease process. An interesting subgroup of RPE tears in this series is that associated with laser photocoagulation because these iatrogenic tears are significant to physicians treating retinal lesions. All such tears developed in eyes treated with krypton red photocoagulation. This suggests a possible predilection for pigment epithelial tearing with the krypton laser which is absorbed by the melanocytes of the pigment epithelium and choroid. The apparent association may, however, at least partially reflect the preponderant use of krypton laser in the macular area. Retinal pigment epithelial tears have been reported after argon laser photocoagulation as well. 2 Retraction of the fibrovascular membrane with RPE tearing during application of laser photocoagulation occurred at the heavy thermal energy levels used to produce a standard white burn. It may be wise, therefore, to moderate treatment initially with careful observation for membrane and RPE retraction, and then proceed to heavier treatment later in the course of photocoagulation. This is especially true with a hypopigmented fibrovascular membrane, where the energy necessary to produce a white retinal burn may inadvertently result in delivery oflarge amounts of thermal energy to the RPE, as Gass has suggested. 5 Retinal pigment epithelial tears may occur at an edge of the neovascular membrane remote from the immediate area of treatment. It is therefore important to be aware at all times of the full extent of the membrane so as to monitor carefully for retraction. Appropriate modification of treatment may be necessary. In four of our cases, rips occurred at some point after laser treatment of a new vessel membrane. Since the
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RPE TEARS
fluorescein angiogram in such cases shows hyperfluorescence at the edge of previous treatment, these rips may be mistaken for recurrent membranes. Retreatment of a mistakenly diagnosed recurrent membrane may worsen the visual acuity by inciting further RPE ripping or damaging macular tissue. A rip itself does not warrant retreatment. Retinal pigment epithelial tears occur in association with choroidal neovascularization as well as with pigment epithelial detachments with or without neovascularization. They may develop during or after laser photocoagulation. Awareness of the potential for RPE tear development as well as its prognostic significance is important in the management of macular disease.
REFERENCES 1. Hoskin A, Bird AC, Sehmi K. Tears of detached retinal pigment epithelium. Br J Ophthalmol1981; 65:417-22. 2. Cantrill HL, Ramsay RC, Knobloch WHo Rips in the pigment epithe· lium. Arch Ophthalmol1983; 101 :1074-9. 3. Coscas G, Quentel G, Pinon F, Soubrane G. Dechirure spontanee de I'epithelium pigmentaire dans la region maculaire. Bull Soc Ophtalmol Fr 1982; 82:815-20. 4. Decker WL, Sanbom GE, Ridley M, et al. Retinal pigment epithelial tears. Ophthalmology 1983; 90:507-12. 5. Gass JDM. Retinal pigment epithelial rip during krypton red laser photocoagulation. Am J Ophthalmol1984; 98:700-6. 6. Green SN, Yarian D. Acute tear of the retinal pigment epithelium. Retina 1983; 3:16-20. 7. Krishan NR, Chandra SR, Stevens TS. Diagnosis and pathogenesis of retinal pigment epithelial tears. Am J Ophthalmol 1985; 100:698707. 8. Laatikainen L. Rupture of retinal pigment epithelial detachment in senile macular disease. Acta Ophthalmol 1983; 61: 1-8. 9. Murphy RP, Yeo JH, Green WR, Patz A. Dehiscences of the pigment epithelium. Trans Am Ophthalmol Soc 1985; 83:63-81. 10. Swanson DE, Kalina RE, Guzak SV. Tears of the retinal pigment epithelium: occurrence in retinal detachments and a chorioretinal scar. Retina 1984; 4:115-8. 11. Traboulsi EI, Jalkh AE. Retinal pigment epithelium tear as a cause of vitreous hemorrhage. Ann Ophthalmol1985; 17:228-35. 12. Tutein Nolthenius PA, Deutman AF. Rips of the retinal pigment epithelium. Int Ophthalmol1985; 8:19-23. 13. Gass JDM. Pathogenesis of tears of the retinal pigment epithelium. Br J Ophthalmol 68:1984; 513-9. 14. Green WR, McDonnell PJ, Yeo JH. Pathologic features of senile macular degeneration. Ophthalmology 1985; 92:615-27.
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