Concomitant Lymphangioma and Arteriovenous Malformation of the Orbit Gustavo E. ColI, M.D., Robert A. Goldberg, M.D., Howard Krauss, M.D., and Bronwyn J. Bateman, M.D. An 8-year-old girl had an orbital-adnexal lymphangioma and ipsilateral orbital and middle cranial fossa arteriovenous malformations. High-resolution magnetic resonance image scanning, orbital ultrasonography, and digital subtraction angiography were used for diagnosis and preoperative assessment. Complications related to this vascular neoplasm included amblyopia, acute hemorrhage with proptosis, exposure keratitis, cosmetic deformity, and recurrent preseptal cellulitis. The girl was treated with both embolization and orbital surgery for recurrent hemorrhage and proptosis. We postulated that the coexistence of a lymphangioma and arteriovenous malformation represents an unusual and extensive maldevelopment of vascular embryogenesis. is an uncommon malformation that develops more frequently in the neck region than it does in the orbitY It is a cystic unencapsulated lobulated mass consisting of one or more fibrous sacs containing strawcolored liquid; histologic features include thinwalled endothelial channels with loose junctions and varying stromal components. Clinically, these tumors may bleed spontaneously with a rapid increase in proptosis. The size may fluctuate with concomitant upper respiratory infections. These lesions are insensitive to irradiation and difficult to treat because the unencapsulated tumor interdigitates with normal LYMPHANGIOMA
Accepted for publication May 21, 1991. From the Divisions of Orbital and Ophthalmic Plastic Surgery and Pediatric Ophthalmology, Jules Stein Eye Institute, UCLA School of Medicine, Los Angeles, California. This study was funded in part by the Karl Kirchgessner Ophthalmology Endowment Fund (Dr. Goldberg). Reprint requests to Robert A. Goldberg, M.D., UCLA, Jules Stein Eye Institute, 100 Stein Plaza, Los Angeles, CA 90024-7006.
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orbital tissue. Ocular complications are common in patients with orbital lymphangioma and include marked astigmatism, hyperopia secondary to tumor pressure on the posterior aspect of the globe, strabismus, cosmetic deformity, and compressive optic neuropathy; all predispose to amblyopia. Surgical debulking is indicated if vision is reduced progressively or the lesion is unsightly. Recently, carbon dioxide laser treatment has been used successfully to debulk the lesion." The association of lymphangiomas and other vascular lesions is not uncommon even in the absence of a fully expressed phacomatosis, such as the Wyburn-Mason syndrome. However, the association of an orbital lymphangioma and a congenital orbital arteriovenous malformation is uncommon. We studied a case of angiographically documented congenital orbital and middle cranial fossa arteriovenous malformations, and an ipsilateral orbital-adnexal lymphangioma.
Case Report An 8-year-old girl had been observed at birth to have a nontender mass involving the right upper and lower eyelids and cheek area; the overlying skin area was discolored. The mass increased slowly in size as the infant developed. When the patient was 1V2 years of age, vision in her right eye was observed to be poor. A contact lens for this eye was fitted; glasses were prescribed for protection. At 2V2 years of age, the child had appreciably reduced vision in the right eye. A subcutaneous, nonpulsatile, compressible mass involving the right upper and lower eyelids with blepharoptosis, and proptosis with lateral displacement of the globe were observed. The right optic nerve was hyperemic. The results of the remainder of the ocular examination were unremarkable. No ocular pulsations or oral lesions
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Fig. 1 (ColI and associates). Top, anterior view; bottom, lateral view of hemorrhage within an orbital lymphangioma, causing proptosis and inferolateral displacement of the right eye. were observed. Orbital-adnexal lymphangioma was diagnosed. Treatment of amblyopia was attempted unsuccessfully by patching the left eye. At 4 years of age, the girl's visual acuity was light perception in the right eye and 20/30 in the left eye (illiterate E). Results of pupillary examination were unremarkable and were without an afferent defect. Extraocular muscle movements were full. On external examination, the entire right upper and lower eyelids were involved with a soft subcutaneous nontender mass and blue discoloration of the overlying skin. The right eye had 4 mm of proptosis, as determined by use of Hertel exophthalmometry. The right upper eyelid had 5 mm of blepharoptosis and could only be opened manually. Eyelashes from the medial aspect of the right upper eyelid were not observed. The tumor mass also involved the right bulbar conjunctiva and eyelid margin. At 4Jh years of age, the patient had a marked increase in proptosis of the right eye. Visual acuity and results of pupillary testing were unchanged. The right eye had 13 mm of propto-
Fig. 2 (ColI and associates). A-scan of the right orbit showing areas of low internal reflectivity with spontaneous spike motions. sis with inferolateral displacement as determined by Hertel exophthalmometry (Fig. 1). Ultrasonography of the right orbit disclosed a
Fig. 3 (ColI and associates). B-scan of the right orbit showing a septated, unencapsulated and round tumor located nasally with areas of hemorrhage.
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Fig. 4 (Coil and associates). Left, Axial view. Right, Coronal view. Magnetic resonance image of the orbit showing a tumor mass involving the right eyelids and right medial orbit and displacing the eye temporally and anteriorly. The right medial orbit contains areas of hemorrhage.
septated, unencapsulated nasal tumor with areas of hemorrhage (Figs. 2 and 3). Magnetic resonance imaging of the orbits showed a large tissue mass involving the right eyelids and the right medial orbit containing areas of probable hemorrhage and displacing the right eye temporally and anteriorly (Fig. 4). Magnetic resonance imaging of the head showed areas of low intensity corresponding to vascular regions lining the anterior aspect of the right middle cranial fossa, with increased flow in the posterior aspect of the right medial orbit (Fig. 5). Lymphangioma with two concomitant separate arteriovenous malformations was diagnosed. Selective angiography of the right middle meningeal artery originating from the external carotid artery showed a medium-sized malformation in the middle cranial fossa that drained into dural branches of the right cavernous sinus; the ophthalmic artery had a residual small malformation within the right orbit that drained into dural branches of the right cavern-
Fig. 5 (Coli and associates). Magnetic resonance image of the head showing an arteriovenous malformation in the right temporal fossa within the middle cranial fossa (arrow).
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Fig. 6 (ColI and associates). Top left, Angiogram of the right middle meningeal artery showing a medium-sized arteriovenous malformation in the middle cranial fossa draining into dural branches of the right cavernous sinus. Top right, Angiogram of the right middle meningeal artery after embolization with polyvinyl particles showing obliteration of the arteriovenous malformation in the middle cranial fossa. Bottom left, Angiogram of the right internal carotid artery and ophthalmic artery showing a small arteriovenous malformation within the right orbit draining into dural branches of the right cavernous sinus.
ous sinus. Shortly thereafter, the malformation in the middle cranial fossa was embolized with polyvinyl alcohol particles (100 IJ.m) by use of guiding catheters under digital subtraction angiography (Fig. 6). Because of technical difficulties with the procedure, the ophthalmic artery could not be catheterized. Because of persistent proptosis, surgery was performed to remove the orbital arteriovenous malformation and intraorbital hematoma. The patient underwent a surgical procedure to clamp the right ophthalmic artery, remove the orbital malformation, and drain an intraorbital hematoma. During
that procedure, it was observed that the orbital malformation was fed by many branches of the ophthalmic artery with drainage into the lateral aspect of the cavernous sinus (Fig. 7). Several episodes of marked right proptosis developed in the ensuing years. One episode was complicated by exposure keratitis and required a temporary tarsorrhaphy. Additionally, the patient developed several episodes of facial cellulitis that required intravenous antibiotics. At the age of 6th years, the patient underwent a second surgical procedure to remove a recurrent right orbital malformation.
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Fig. 7 (ColI and associates). Angiogram of the right internal carotid artery after excision of the right orbital arteriovenous malformation showing a surgical clip across the ophthalmic artery.
Discussion
Lymphangioma and arteriovenous malformation in our patient were diagnosed on the basis of clinical signs at initial examination and results of imaging studies; a biopsy was not necessary. Harris and associates! reviewed 30 cases of orbital lymphangioma. In almost all cases the diagnosis was provided by imaging studies and clinical signs at initial examination. Our patient demonstrated many of the reported complications of orbital-adnexal lymphangioma including amblyopia, hemorrhagic proptosis, cosmetic deformity, and recurrent infections. The unusual coexistence of the orbital neoplasms and the clinical course necessitated multiple invasive procedures. Whether lymphangiomas represent a venous malformation or a distinct entity is controversial. In a review of 67 cases of vascular anomalies, Wright6 concluded that the majority of lesions fitting the histologic description of lymphangioma represented congenital orbital varices. Vascular connections of the lesions with the superficial veins in the orbit, demonstrated by venography, determined his view. In a review of 19 cases of orbital lymphangioma, Iliff and Green! found no abnormality of these lesions consistent with orbital varices by use of venography. They concluded that lymphangiomas represent a distinct morphologic entity. As it is generally believed that the orbit usually contains no lymphatic channels, the origin of lymphangioma is uncertain. Jones'
suggested that in some patients, there may be embryonal lymphatic rests in the orbit. He demonstrated in animals that india ink injected into the extracellular space of the orbit appeared in the cervical lymph nodes. Many orbital lymphangiomas have anterior eyelid and conjunctival connections that may be the site of origin. [akobiec and Font" believed that lymphangiomas may represent a vascular anlage that was misdirected during embryonic development. Rootman and associates? suggested that orbital lymphangioma is a developmental anomaly that is a result of sequestration and failure to communicate with the lymphatic system. The fundamental differentiation of this vascular neoplasm should be determined on the basis of the lack of communication with the systemic circulation. Furthermore, they suggest that the histopathologic features of orbital lymphangioma parallel the histologic findings of similar lesions in the head and neck. Therefore, orbital lymphangiomas should be classified as tumors of lymphangiomatous origin. The stages of differentiation and maturation in vascular embryogenesis provide some basis for understanding the origin of lymphangiomas, as it conforms to the arrest of a particular embryonic development. The capillary network stage is an embryologic development of the mesenchymal primordia. With further differentiation, these primitive vessels penetrate deeper into the subcutaneous layer." The next stage of differentiation, retiform, is characterized by the establishment of venous, arterial, and capillary systems. In the final stage of development, maturation of venous and lymphatic systems predominates; aberrations in the progressions of this stage result in Iymphangtomas."" If vascular tumors are caused by aberrations during vascular embryogenesis, one would expect to find different forms of vascular tumors coexisting in the same individual. In a study by Formon, Luessenhop, and Limaye," five of 25 patients with angiographically documented congenital arteriovenous malformations of the head and neck had associated vascular malformations of the eye. Scavone and associates" reported a case of a patient with a large congenital intracranial arteriovenous malformation and a facial lymphangioma. References 1. Jones, I. S.: Lymphangiomas of the ocular adnexae. An analysis of sixty-two cases. Am. J. Ophthalmol. 51:481,1961.
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2. Iliff, W. J., and Green, W. R.: Orbitallymphangiomas. Ophthalmology 86:914, 1979. 3. Kennerdell, J. S., Maroon, J. c.. Garrity, J. A., and Abla, A. A.: Surgical management of orbital lymphangiomas with the carbon dioxide laser. Am. J. Ophthalmol. 102:308, 1986. 4. Harris, G. J., Sakol, P. J., Bonavolanta, G., and de Conciliis, c.: An analysis of thirty cases of orbital lymphangiomas. Pathophysiologic consideration and management recommendations. Ophthalmology 97:12, 1990. 5. Wright, J. E.: Orbital vascular anomalies. Trans. Am. Acad. Ophthalmol. Otolaryngol. 78:0P616, 1974. 6. [akobiec, F. A., and Font, R. L.: Orbit. In Spencer, W. H. (ed.): Ophthalmic Pathology. An Atlas and Textbook, ed. 3, vol. 3. Philadelphia, W. B. Saunders, 1986, pp. 2533-2538. 7. Rootman, J., Hay, E., Graeb, D., and Millers, R.: Orbital-adnexal lymphangiomas. A spectrum of hemodynamically isolated vascular hamartomas. Ophthalmology 93:1558, 1986.
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8. Blackfield, H. M., Morris, W. J., and Torrey, F. A.: A preliminary report of a 10-year study. Plast. Reconstr. Surg. 26:326, 1960. 9. Mulliken, J. B., and Glowacki, J.: Hemangiomas and vascular malformations in infants and children. A classification based on endothelial characteristics. Plast. Reconstr. Surg. 69:412, 1982. 10. Stal, S., Hamilton, S., and Spira, M.: Hemangiomas, lymphangiomas and vascular malformations of the head and neck. Otolaryngol. Clin. North Am. 19:769,1986. 11. Forman, A. R., Luessenhop, A. J., and Limaye, S. R.: Ocular findings in patients with arteriovenous malformations of the head and neck. Am. J. Ophthalmol. 79:626, 1975. 12. Scavone, C., Pascual-Castroviejo, I., Tenedro, A., and Villarejo, J.: Giant intracranial arteriovenous malformation and facial lymphangioma. An. Espan. Pediatr. 13:589, 1980.
OPHTHALMIC MINIATURE
A lake is the landscape's most beautiful and expressive feature. It is earth's eye; looking into which the beholder measures the depth of his own nature. The fluviatile trees next [to] the shore are the slender eyelashes which fringe it, and the wooded hills and cliffs around are its overhanging brows. Henry D. Thoreau, Walden Princeton, Princeton University Press, 1971, p. 186
Accepted for publication May 21, 1991. From the Divisions of Orbital and Ophthalmic Plastic Surgery and Pediatric Ophthalmology, Jules Stein Eye Institute, UCLA School of Medicine, Los Angeles, California. This study was funded in part by the Karl Kirchgessner Ophthalmology Endowment Fund (Dr. Goldberg). Reprint requests to Robert A. Goldberg, M.D., UCLA, Jules Stein Eye Institute, 100 Stein Plaza, Los Angeles, CA 90024-7006.
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orbital tissue. Ocular complications are common in patients with orbital lymphangioma and include marked astigmatism, hyperopia secondary to tumor pressure on the posterior aspect of the globe, strabismus, cosmetic deformity, and compressive optic neuropathy; all predispose to amblyopia. Surgical debulking is indicated if vision is reduced progressively or the lesion is unsightly. Recently, carbon dioxide laser treatment has been used successfully to debulk the lesion." The association of lymphangiomas and other vascular lesions is not uncommon even in the absence of a fully expressed phacomatosis, such as the Wyburn-Mason syndrome. However, the association of an orbital lymphangioma and a congenital orbital arteriovenous malformation is uncommon. We studied a case of angiographically documented congenital orbital and middle cranial fossa arteriovenous malformations, and an ipsilateral orbital-adnexal lymphangioma.
Case Report An 8-year-old girl had been observed at birth to have a nontender mass involving the right upper and lower eyelids and cheek area; the overlying skin area was discolored. The mass increased slowly in size as the infant developed. When the patient was 1V2 years of age, vision in her right eye was observed to be poor. A contact lens for this eye was fitted; glasses were prescribed for protection. At 2V2 years of age, the child had appreciably reduced vision in the right eye. A subcutaneous, nonpulsatile, compressible mass involving the right upper and lower eyelids with blepharoptosis, and proptosis with lateral displacement of the globe were observed. The right optic nerve was hyperemic. The results of the remainder of the ocular examination were unremarkable. No ocular pulsations or oral lesions
©AMERICAN JOURNAL OF OPHTHALMOLOGY
112:200-205,
AUGUST,
1991
Vol. 112, No.2
Orbital Lymphangioma and Arteriovenous Malformation
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Fig. 1 (ColI and associates). Top, anterior view; bottom, lateral view of hemorrhage within an orbital lymphangioma, causing proptosis and inferolateral displacement of the right eye. were observed. Orbital-adnexal lymphangioma was diagnosed. Treatment of amblyopia was attempted unsuccessfully by patching the left eye. At 4 years of age, the girl's visual acuity was light perception in the right eye and 20/30 in the left eye (illiterate E). Results of pupillary examination were unremarkable and were without an afferent defect. Extraocular muscle movements were full. On external examination, the entire right upper and lower eyelids were involved with a soft subcutaneous nontender mass and blue discoloration of the overlying skin. The right eye had 4 mm of proptosis, as determined by use of Hertel exophthalmometry. The right upper eyelid had 5 mm of blepharoptosis and could only be opened manually. Eyelashes from the medial aspect of the right upper eyelid were not observed. The tumor mass also involved the right bulbar conjunctiva and eyelid margin. At 4Jh years of age, the patient had a marked increase in proptosis of the right eye. Visual acuity and results of pupillary testing were unchanged. The right eye had 13 mm of propto-
Fig. 2 (ColI and associates). A-scan of the right orbit showing areas of low internal reflectivity with spontaneous spike motions. sis with inferolateral displacement as determined by Hertel exophthalmometry (Fig. 1). Ultrasonography of the right orbit disclosed a
Fig. 3 (ColI and associates). B-scan of the right orbit showing a septated, unencapsulated and round tumor located nasally with areas of hemorrhage.
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Fig. 4 (Coil and associates). Left, Axial view. Right, Coronal view. Magnetic resonance image of the orbit showing a tumor mass involving the right eyelids and right medial orbit and displacing the eye temporally and anteriorly. The right medial orbit contains areas of hemorrhage.
septated, unencapsulated nasal tumor with areas of hemorrhage (Figs. 2 and 3). Magnetic resonance imaging of the orbits showed a large tissue mass involving the right eyelids and the right medial orbit containing areas of probable hemorrhage and displacing the right eye temporally and anteriorly (Fig. 4). Magnetic resonance imaging of the head showed areas of low intensity corresponding to vascular regions lining the anterior aspect of the right middle cranial fossa, with increased flow in the posterior aspect of the right medial orbit (Fig. 5). Lymphangioma with two concomitant separate arteriovenous malformations was diagnosed. Selective angiography of the right middle meningeal artery originating from the external carotid artery showed a medium-sized malformation in the middle cranial fossa that drained into dural branches of the right cavernous sinus; the ophthalmic artery had a residual small malformation within the right orbit that drained into dural branches of the right cavern-
Fig. 5 (Coli and associates). Magnetic resonance image of the head showing an arteriovenous malformation in the right temporal fossa within the middle cranial fossa (arrow).
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Fig. 6 (ColI and associates). Top left, Angiogram of the right middle meningeal artery showing a medium-sized arteriovenous malformation in the middle cranial fossa draining into dural branches of the right cavernous sinus. Top right, Angiogram of the right middle meningeal artery after embolization with polyvinyl particles showing obliteration of the arteriovenous malformation in the middle cranial fossa. Bottom left, Angiogram of the right internal carotid artery and ophthalmic artery showing a small arteriovenous malformation within the right orbit draining into dural branches of the right cavernous sinus.
ous sinus. Shortly thereafter, the malformation in the middle cranial fossa was embolized with polyvinyl alcohol particles (100 IJ.m) by use of guiding catheters under digital subtraction angiography (Fig. 6). Because of technical difficulties with the procedure, the ophthalmic artery could not be catheterized. Because of persistent proptosis, surgery was performed to remove the orbital arteriovenous malformation and intraorbital hematoma. The patient underwent a surgical procedure to clamp the right ophthalmic artery, remove the orbital malformation, and drain an intraorbital hematoma. During
that procedure, it was observed that the orbital malformation was fed by many branches of the ophthalmic artery with drainage into the lateral aspect of the cavernous sinus (Fig. 7). Several episodes of marked right proptosis developed in the ensuing years. One episode was complicated by exposure keratitis and required a temporary tarsorrhaphy. Additionally, the patient developed several episodes of facial cellulitis that required intravenous antibiotics. At the age of 6th years, the patient underwent a second surgical procedure to remove a recurrent right orbital malformation.
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Fig. 7 (ColI and associates). Angiogram of the right internal carotid artery after excision of the right orbital arteriovenous malformation showing a surgical clip across the ophthalmic artery.
Discussion
Lymphangioma and arteriovenous malformation in our patient were diagnosed on the basis of clinical signs at initial examination and results of imaging studies; a biopsy was not necessary. Harris and associates! reviewed 30 cases of orbital lymphangioma. In almost all cases the diagnosis was provided by imaging studies and clinical signs at initial examination. Our patient demonstrated many of the reported complications of orbital-adnexal lymphangioma including amblyopia, hemorrhagic proptosis, cosmetic deformity, and recurrent infections. The unusual coexistence of the orbital neoplasms and the clinical course necessitated multiple invasive procedures. Whether lymphangiomas represent a venous malformation or a distinct entity is controversial. In a review of 67 cases of vascular anomalies, Wright6 concluded that the majority of lesions fitting the histologic description of lymphangioma represented congenital orbital varices. Vascular connections of the lesions with the superficial veins in the orbit, demonstrated by venography, determined his view. In a review of 19 cases of orbital lymphangioma, Iliff and Green! found no abnormality of these lesions consistent with orbital varices by use of venography. They concluded that lymphangiomas represent a distinct morphologic entity. As it is generally believed that the orbit usually contains no lymphatic channels, the origin of lymphangioma is uncertain. Jones'
suggested that in some patients, there may be embryonal lymphatic rests in the orbit. He demonstrated in animals that india ink injected into the extracellular space of the orbit appeared in the cervical lymph nodes. Many orbital lymphangiomas have anterior eyelid and conjunctival connections that may be the site of origin. [akobiec and Font" believed that lymphangiomas may represent a vascular anlage that was misdirected during embryonic development. Rootman and associates? suggested that orbital lymphangioma is a developmental anomaly that is a result of sequestration and failure to communicate with the lymphatic system. The fundamental differentiation of this vascular neoplasm should be determined on the basis of the lack of communication with the systemic circulation. Furthermore, they suggest that the histopathologic features of orbital lymphangioma parallel the histologic findings of similar lesions in the head and neck. Therefore, orbital lymphangiomas should be classified as tumors of lymphangiomatous origin. The stages of differentiation and maturation in vascular embryogenesis provide some basis for understanding the origin of lymphangiomas, as it conforms to the arrest of a particular embryonic development. The capillary network stage is an embryologic development of the mesenchymal primordia. With further differentiation, these primitive vessels penetrate deeper into the subcutaneous layer." The next stage of differentiation, retiform, is characterized by the establishment of venous, arterial, and capillary systems. In the final stage of development, maturation of venous and lymphatic systems predominates; aberrations in the progressions of this stage result in Iymphangtomas."" If vascular tumors are caused by aberrations during vascular embryogenesis, one would expect to find different forms of vascular tumors coexisting in the same individual. In a study by Formon, Luessenhop, and Limaye," five of 25 patients with angiographically documented congenital arteriovenous malformations of the head and neck had associated vascular malformations of the eye. Scavone and associates" reported a case of a patient with a large congenital intracranial arteriovenous malformation and a facial lymphangioma. References 1. Jones, I. S.: Lymphangiomas of the ocular adnexae. An analysis of sixty-two cases. Am. J. Ophthalmol. 51:481,1961.
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2. Iliff, W. J., and Green, W. R.: Orbitallymphangiomas. Ophthalmology 86:914, 1979. 3. Kennerdell, J. S., Maroon, J. c.. Garrity, J. A., and Abla, A. A.: Surgical management of orbital lymphangiomas with the carbon dioxide laser. Am. J. Ophthalmol. 102:308, 1986. 4. Harris, G. J., Sakol, P. J., Bonavolanta, G., and de Conciliis, c.: An analysis of thirty cases of orbital lymphangiomas. Pathophysiologic consideration and management recommendations. Ophthalmology 97:12, 1990. 5. Wright, J. E.: Orbital vascular anomalies. Trans. Am. Acad. Ophthalmol. Otolaryngol. 78:0P616, 1974. 6. [akobiec, F. A., and Font, R. L.: Orbit. In Spencer, W. H. (ed.): Ophthalmic Pathology. An Atlas and Textbook, ed. 3, vol. 3. Philadelphia, W. B. Saunders, 1986, pp. 2533-2538. 7. Rootman, J., Hay, E., Graeb, D., and Millers, R.: Orbital-adnexal lymphangiomas. A spectrum of hemodynamically isolated vascular hamartomas. Ophthalmology 93:1558, 1986.
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8. Blackfield, H. M., Morris, W. J., and Torrey, F. A.: A preliminary report of a 10-year study. Plast. Reconstr. Surg. 26:326, 1960. 9. Mulliken, J. B., and Glowacki, J.: Hemangiomas and vascular malformations in infants and children. A classification based on endothelial characteristics. Plast. Reconstr. Surg. 69:412, 1982. 10. Stal, S., Hamilton, S., and Spira, M.: Hemangiomas, lymphangiomas and vascular malformations of the head and neck. Otolaryngol. Clin. North Am. 19:769,1986. 11. Forman, A. R., Luessenhop, A. J., and Limaye, S. R.: Ocular findings in patients with arteriovenous malformations of the head and neck. Am. J. Ophthalmol. 79:626, 1975. 12. Scavone, C., Pascual-Castroviejo, I., Tenedro, A., and Villarejo, J.: Giant intracranial arteriovenous malformation and facial lymphangioma. An. Espan. Pediatr. 13:589, 1980.
OPHTHALMIC MINIATURE
A lake is the landscape's most beautiful and expressive feature. It is earth's eye; looking into which the beholder measures the depth of his own nature. The fluviatile trees next [to] the shore are the slender eyelashes which fringe it, and the wooded hills and cliffs around are its overhanging brows. Henry D. Thoreau, Walden Princeton, Princeton University Press, 1971, p. 186
