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Pseudotumor of the orbit in early childhood
Pseudotumor of the Orbit in Early Childhood Julia L. Stevens, M D , Paul J. Ryehwalski, M D , Robert S. Baker, M D , and Richard S. Kielar, M D
Orbital pseudotumor, also known as idiopathic orbital inflanunation, is defined as a nonspecific, nonneoplastic inflammatory process of the orbit without identiflable local or systemic causes. The disorder, first described by Birch-Hirschfield in 1905, I is more prevalent in the adult population than in the pediatric population. In our study we discuss two cases of pseudotumor of the orbit in children less than 18 months old. This report will highlight the evaluation and management of pediatric orbital pseudotumor and the importance of its inclusion in the differential diagnosis of orbital disorders in young children. R E P O R T O F CASES Case 1 is a 10-month-old boy with a 1-month history of intermittent right orbital inflammation and edema. The child's pediatrician diagnosed preseptal cellulitis, and the patient was treated with a 10-day course of amoxicillin without improvement. The patient subsequently received a 2week course of oral cefprozil and topical sulfacetamide 10% ophthalmic solution with some improvement; however, the inflammatory signs and symptoms recurred. He was referred to the pediatric ophthalmology service for further evaluation. The patient was afebrile on admission, and examination documented significant right periorbital erythema and edema (Figure 1, A). Epiphora and mucopurulent discharge were present, and purulent debris was expressed from the right nasolacrimal sac. No proptosis or motility restriction was noted. Visual acuity was normal. T h e patient was felt to have preseptal cellulitis resulting from chronic dacryocystitis. No blood cultures or other laboratory studies were performed. After 2 days of intravenous ampicillin-sulbactam, less periorbital edema and erythema were noted, although the nasolacrimal duct obstruction persisted. The patient underwent an uncomplicated nasolacrimal duct probing under general anesthesia. A large From the Department of Ophthalmology, University of Kentucky, Lexington, Kentucky. Supported in part by an unrestricted grant from Research to Prevent Blindness, Inc., to the University of Kentucky Department of Ophthalmology. Presented at the Twenty-first Annual Meeting of the American Associationfor Pediatric Ophthalmology and Strabi~wms, Orlando, Florida, April 5-9, 1995. Submitted January 29, 199Z Revision accepted October 11, 199Z J AAPOS 1998;2:120-3. Reprint requests:Julia L. Stevens, MD, E-302 Kentucky Clinic, University of Kentucky, Department of Ophthalmology, Lexington, KY40536-0284. Copyright © 1998 by the American Associatianfor Pediatric Ophthalmology and Strabismus. 1091-8531/98 $5.00 + 0 75/1/88078
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degree of restriction to the passage of a nasolacrimal probe was noted at the superior margin of the nasolacrimal sac. The patient was discharged on a 3-week course of oral amoxicillin-clavulanate potassium. Despite resolution of the epiphora and discharge, the patient continued to have intermittent swelling and erythema of the right orbit. Three weeks later he developed proptosis and resistance to retropulsion of the right globe. A computed tomographic scan documented an orbital mass lesion involving the right lateral and inferotemporal orbit, adjacent to the right lateral rectus muscle (Figure 1, B). Bony hyperplasia was present along the posterolateral wall of the right maxillary sinus and the right orbital wall. No opacification of the sinuses was appreciated. A lateral orbitotomy with orbital biopsy was performed because of the high suspicion for a malignant process. The right lateral and posterior orbit were filled with a grayishwhite tissue. Histopathologic study showed dense fibrous connective tissue with scattered areas of chronic inflammatory cells, consistent with sclerosing orbital pseudotumor (Figure 1, C). Laboratory studies were notable for an elevated peripheral blood eosinophil count of 6% and an erythrocyte sedimentation rate of 20. The patient was given 2 days of intravenous methylprednisolone, a 20 mg loading dose and then 2.5 mg every 6 hours. This was followed by a 10-day course of oral prednisone, 20 mg daily for 2 days and then 10 mg daily for 2 days and finally 5 mg for 6 days. The child had an excellent response to steroid therapy, with resolution of the orbital inflammatory process. A repeat computed tomographic scan 2 months after biopsy documented complete clearance of the orbital inflammatory mass. Case 2 is a previously healthy 17-month-old girl with a 2month history of persistent swelling of the right upper hd. The child had a history of frequent sinus infections. Examination showed fight eyelid edema and erythema; the hds were not tender to palpation. A course of prednisone 2 mg/kg/day had been tried with some improvement in the swelling, but it reotrred when the steroids were discontinued. The patient was then treated with intravenous ceftriaxone 50 mg/kg/day, again with a mild decrease in the lid swelling but with subsequent recurrence. She was referred to the pediatric ophthalmology service for evaluation. Examination revealed swelling of the right upper hd and limited supraduction of the right eye with normal visual acuity (Figure 2, A). A magnetic resonance imaging scan showed an extraconal mass involving the right lacrimal gland and extending into the posterior orbit. There was also diffuse involvement of the right upper eyelid (Figure 2, B). The Journal of AAPOS
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FIG. 1. A, Ten-month-old boy with right proptosis and mild periorbital erythema. B, Computed tomographic scan shows extraconal mass in right orbit with involvement of right lateral rectus muscle. There is no evidence of bone destruction. C, Orbital biopsy specimen of case 1. Histologic features typical of orbital pseudotumor: polymorphous inflammatory response together with collagen deposition. (Hematoxylin and eosin stain, original magnification ×40.)
peripheral blood eosinophil count was 8%. Orbital exploration documented an ill-defined, yellow-tan mass involving but not confined to the lacrimal gland. Subtotal excision of the mass was performed through a lateral orbitotomy approach. Pathologic examination showed an acute and chronic inflammatory infiltrate with a large number of eosinophils (Figure 3). The lobular acinar structure of the lacrimal gland was replaced by fibrous connective tissue. The diagnosis of idiopathic orbital inflammation was made, and the child was initially placed on prednisone 15 mg daily with a slow taper over the succeeding 2 months. Three months later complete resolution of the orbital process was noted and ocular motility and visual acuity were normal.
DISCUSSION Orbital pseudotumor accounts for approximately 16% of all cases of unilateral proptosis in adults. 1 Although orbital pseudotumor is more prevalent in adults, it has also been
reported in children. In a study by Blodi and Gass 2 16% of patients with orbital pseudotumor were less than 20 years old, and the youngest was 8 years old. Likewise, in a 227 patient study by Mottow and Jakobiec 3 6.6% of the patients were less than 20 years old; the youngest was 3 years old. Grossniklaus et al. 4 and Berger et al. s have reported the only other patients in the literature with orbital pseudotumor at less than 3 years old. The clinical manifestations of this illness include orbital or periorbital edema, erythema, proptosis, palpable mass lesions, orbital congestion, ptosis, photophobia, tenderness, diplopia, and pain with ocular motility. Constitutional signs including headache, emesis, sore throat, anorexia, abdominal distress, lethargy, and weight loss were seen in 53% of pediatric patients studied by Mottow-Lippa et al. 6 These symptoms are rarely reported by adult patients. These authors also describe three distinguishing features in the pediatric population: (1) bilaterality is common, seen in 45% of their patients, but is rare in
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FI6.3. Biopsy specimen of orbital tissue in case 2 shows infiltration with dense fibrous connective tissue and chronic inflammatory infiltrate including numerous eosinophils. (Hematoxylin and eosin stain, original magnification x125.) TABLE. Neuroimaging features of orbital pseudotumor 1. Proptosis 2. Contrast enhancement and infiltration of orbital tissue 3. Extraecular muscle enlargement 4. Absence of contiguous paranasal sinus disease 5. Absence of bony erosion or distortion of orbital contents
FI6.2. A, Seventeen-month-old girl with erythema and edema of right upper eyelid. B, Magnetic resonance imaging scan documents extraconal mass involving right lacrimal gland. There is no evidence of bone destruction.
adults, (2) associated iritis occurs in 25% of children, usually indicates a poor prognosis, and may be the presenting sign of the disease, 7 and (3) trauma may precede the inflammatory process in children. 6 Additionally, peripheral eosinophilia is seen more commonly in the pediatric patient with orbital pseudotumor than in the adult patient. The etiology of pseudotumor of the orbit is unknown; however, there are three theories as to its pathogenesis. It is thought by some to be the result of an immune reaction because of the increased tendency of some of these children to develop autoimmune disorders in adulthood. 1 Circulating antibodies to extraocular muscle proteins have been found in some patients. There is also an association between orbital pseudotumor and preceding viral respiratory tract infections, suggesting an immune response to a viral or bacterial antigen. Others note that the histopathologic findings are similar to those of systemic fibrotic disorders. They postulate an aberrant immune-mediated production of fibrogenic cytokines such as transforming growth factor-J3 and platelet-derived growth factor, which
both lead to fibroblast proliferation and extracellular matrix deposition. 7 Pseudotumor of the orbit is often a diagnosis of exclusion, and therefore it is important to approach the evaluation with a thorough differential diagnosis. Other entities seen in infants and children include orbital cellulitis, thyroid ophthalmopathy, rhabdomyosarcoma, leukemia, histiocytosis, sinus mucocoele, dermoid cyst, and optic nerve glioma. Typically, laboratory studies in orbital pseudotumor are normal, with the exception of an elevated leukocyte count, an elevated erythrocyte sedimentation rate, and peripheral blood eosinophilia. 6 Laboratory studies will often result in values resembling values obtained in patients with periorbital or orbital cellulitis. Evaluation should always exclude an infectious cause for orbital inflammation. Orbital imaging will usually differentiate orbital pseudotumor from orbital cellulitis. Computed tomographic findings consistent with pseudotumor include presence of a diffuse orbital mass, uveoscleral thickening, contrast enhancement of Tenon's potential space, proptosis, and optic nerve and extraocular muscle enlargement. 8 Bone erosion or destruction is extremely rare in orbital pseudotumor, but it has been reported. 9 A helpful diagnostic point is the presence of concomitant sinusitis, usually seen with orbital cellulitis but rarely present in orbital pseudotumor. We recommend the following laboratory studies in the evaluation of a child with signs and symptoms of an orbital mass lesion: complete blood cell count with absolute
]ournal ofAAPOS Volume 2 Number 2 April 1998 eosinophil count, erythrocyte sedimentation rate, and thyroid function studies. Neuroimaging studies with either a computed tomographic or magnetic resonance scan are indicated in patients with suspected orbital pseudotumor. The imaging pattern reveals diagnostic findings outlined in the Table. Unlike the situation in orbital malignancies, bone erosion or destruction is rare. 7 Our cases were notable in that the inflammatory process occurred in a discrete area resembling a mass lesion, which is more common in the chronic sclerosing form of the disease. Histopathologically, pseudotumor of the orbit consists of nonspecific polyrnorphic lymphocytic infiltrates, with eosinophils, polymorphonuclear leukocytes, and macrophages. Increased connective tissue with edema and fibrosis is also commonly seen. Extensive fibrosis formation on the biopsy specimen is termed sclerosing orbital pseudotumor. Treatment with systemic corticosteroid therapy, 1.0 to 1.5 mg/kg/day in children, often gives symptomatic relief within 24 to 48 hours. Steroids are slowly tapered if the patient remains asymptomatic. Because of the rapid response to corticosteroid treatment, a trial dose of prednisone can be helpful in confirming the diagnosis. Orbital biopsy is recommended for cases suspicious for an orbital malignancy after evaluation with the imaging and serum studies that were mentioned above. Biopsy is also recommended when a poor or equivocal response to steroids is seen. 1° Low-dose irradiation is typically reserved for elderly patients who have lymphoid-type pseudotumor, are unresponsive to steroids, or in whom steroids are contraindicated.10 Surgical decompression is usually indicated only if medical management has failed, but it has recently been suggested as a good approach to patients with a focal or
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anteriorly located tumor. 7 T h e long-term prognosis is favorable, although a 30% recurrence rate is reported. ~ Recurrence is most commonly seen in patients with bilateral disease and iritis, and in severe cases residual proptosis and visual impairment may occur. We have described two patients with the development of orbital pseudotumor before age 18 months. Both of these children were initially treated for infectious conditions but eventually responded nicely to initiation of steroid therapy. These children emphasize the need to include pseudotumor in the differential diagnosis of orbital processes in infants and young children. References
1. Brown DH, MacRae DL, Allen LH. Orbital pseudotumors. J Otolaryngol 1988;17:4:164-8. 2. Blodi FC, Gass J. Inflammatory pseudotumor of the orbit. Br J Ophthalmol 1968;52:79-93. 3. Mot-towLS,JakobiecFA. Idiopathicinflammatoryorbital psendommor in childhood.Arch Ophthalmol 1978;96:1410-7. 4. Grossnildaus HE, Lass JH, Abramowsky CR, Levine MR. Childhood orbital pseudotumor.Ann Ophthalmol 1985;17:372-7. 5. BergerJW,RubinPAD,JakobieeFA. Pediatricorbitalpseudotumor: case report and review of the literature. Int Ophthalmol Clin 1996;30:161-77. 6. Mottow-LippaL, Jakobiec FA, Smith M. Idiopathicinflammatory orbital pseudotumor in childhood. Ophthalmology 1981;88:6: 565-74. 7. MombaertsIL, GoldschmedingR, SchlingemannRO, KoorneefL. What is orbital pseudotumor?Surv Ophthalmol 1996;41:66-78. 8. BloomJN, Graviss ER, Byrne BJ. Orbital pseudotumorin the differential diagnosis of pediatric uveitis. J Pediatr Ophthalmol Strabismus 1992;29:1:59-63. 9. Flanders AE, Mafee Mr, Rao VM, Choi KH. Characteristics of orbital pseudotumors and other orbital inflammatoryprocesses.J Comput AssistTomogr 1989;13:40-7. 10. MaurielloJA, FlanaganJC. Managementof orbital inflammatory disease: a protocol. Surv Ophthalmol 1984;29:104-16.
Orbital pseudotumor, also known as idiopathic orbital inflanunation, is defined as a nonspecific, nonneoplastic inflammatory process of the orbit without identiflable local or systemic causes. The disorder, first described by Birch-Hirschfield in 1905, I is more prevalent in the adult population than in the pediatric population. In our study we discuss two cases of pseudotumor of the orbit in children less than 18 months old. This report will highlight the evaluation and management of pediatric orbital pseudotumor and the importance of its inclusion in the differential diagnosis of orbital disorders in young children. R E P O R T O F CASES Case 1 is a 10-month-old boy with a 1-month history of intermittent right orbital inflammation and edema. The child's pediatrician diagnosed preseptal cellulitis, and the patient was treated with a 10-day course of amoxicillin without improvement. The patient subsequently received a 2week course of oral cefprozil and topical sulfacetamide 10% ophthalmic solution with some improvement; however, the inflammatory signs and symptoms recurred. He was referred to the pediatric ophthalmology service for further evaluation. The patient was afebrile on admission, and examination documented significant right periorbital erythema and edema (Figure 1, A). Epiphora and mucopurulent discharge were present, and purulent debris was expressed from the right nasolacrimal sac. No proptosis or motility restriction was noted. Visual acuity was normal. T h e patient was felt to have preseptal cellulitis resulting from chronic dacryocystitis. No blood cultures or other laboratory studies were performed. After 2 days of intravenous ampicillin-sulbactam, less periorbital edema and erythema were noted, although the nasolacrimal duct obstruction persisted. The patient underwent an uncomplicated nasolacrimal duct probing under general anesthesia. A large From the Department of Ophthalmology, University of Kentucky, Lexington, Kentucky. Supported in part by an unrestricted grant from Research to Prevent Blindness, Inc., to the University of Kentucky Department of Ophthalmology. Presented at the Twenty-first Annual Meeting of the American Associationfor Pediatric Ophthalmology and Strabi~wms, Orlando, Florida, April 5-9, 1995. Submitted January 29, 199Z Revision accepted October 11, 199Z J AAPOS 1998;2:120-3. Reprint requests:Julia L. Stevens, MD, E-302 Kentucky Clinic, University of Kentucky, Department of Ophthalmology, Lexington, KY40536-0284. Copyright © 1998 by the American Associatianfor Pediatric Ophthalmology and Strabismus. 1091-8531/98 $5.00 + 0 75/1/88078
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April 1998
degree of restriction to the passage of a nasolacrimal probe was noted at the superior margin of the nasolacrimal sac. The patient was discharged on a 3-week course of oral amoxicillin-clavulanate potassium. Despite resolution of the epiphora and discharge, the patient continued to have intermittent swelling and erythema of the right orbit. Three weeks later he developed proptosis and resistance to retropulsion of the right globe. A computed tomographic scan documented an orbital mass lesion involving the right lateral and inferotemporal orbit, adjacent to the right lateral rectus muscle (Figure 1, B). Bony hyperplasia was present along the posterolateral wall of the right maxillary sinus and the right orbital wall. No opacification of the sinuses was appreciated. A lateral orbitotomy with orbital biopsy was performed because of the high suspicion for a malignant process. The right lateral and posterior orbit were filled with a grayishwhite tissue. Histopathologic study showed dense fibrous connective tissue with scattered areas of chronic inflammatory cells, consistent with sclerosing orbital pseudotumor (Figure 1, C). Laboratory studies were notable for an elevated peripheral blood eosinophil count of 6% and an erythrocyte sedimentation rate of 20. The patient was given 2 days of intravenous methylprednisolone, a 20 mg loading dose and then 2.5 mg every 6 hours. This was followed by a 10-day course of oral prednisone, 20 mg daily for 2 days and then 10 mg daily for 2 days and finally 5 mg for 6 days. The child had an excellent response to steroid therapy, with resolution of the orbital inflammatory process. A repeat computed tomographic scan 2 months after biopsy documented complete clearance of the orbital inflammatory mass. Case 2 is a previously healthy 17-month-old girl with a 2month history of persistent swelling of the right upper hd. The child had a history of frequent sinus infections. Examination showed fight eyelid edema and erythema; the hds were not tender to palpation. A course of prednisone 2 mg/kg/day had been tried with some improvement in the swelling, but it reotrred when the steroids were discontinued. The patient was then treated with intravenous ceftriaxone 50 mg/kg/day, again with a mild decrease in the lid swelling but with subsequent recurrence. She was referred to the pediatric ophthalmology service for evaluation. Examination revealed swelling of the right upper hd and limited supraduction of the right eye with normal visual acuity (Figure 2, A). A magnetic resonance imaging scan showed an extraconal mass involving the right lacrimal gland and extending into the posterior orbit. There was also diffuse involvement of the right upper eyelid (Figure 2, B). The Journal of AAPOS
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FIG. 1. A, Ten-month-old boy with right proptosis and mild periorbital erythema. B, Computed tomographic scan shows extraconal mass in right orbit with involvement of right lateral rectus muscle. There is no evidence of bone destruction. C, Orbital biopsy specimen of case 1. Histologic features typical of orbital pseudotumor: polymorphous inflammatory response together with collagen deposition. (Hematoxylin and eosin stain, original magnification ×40.)
peripheral blood eosinophil count was 8%. Orbital exploration documented an ill-defined, yellow-tan mass involving but not confined to the lacrimal gland. Subtotal excision of the mass was performed through a lateral orbitotomy approach. Pathologic examination showed an acute and chronic inflammatory infiltrate with a large number of eosinophils (Figure 3). The lobular acinar structure of the lacrimal gland was replaced by fibrous connective tissue. The diagnosis of idiopathic orbital inflammation was made, and the child was initially placed on prednisone 15 mg daily with a slow taper over the succeeding 2 months. Three months later complete resolution of the orbital process was noted and ocular motility and visual acuity were normal.
DISCUSSION Orbital pseudotumor accounts for approximately 16% of all cases of unilateral proptosis in adults. 1 Although orbital pseudotumor is more prevalent in adults, it has also been
reported in children. In a study by Blodi and Gass 2 16% of patients with orbital pseudotumor were less than 20 years old, and the youngest was 8 years old. Likewise, in a 227 patient study by Mottow and Jakobiec 3 6.6% of the patients were less than 20 years old; the youngest was 3 years old. Grossniklaus et al. 4 and Berger et al. s have reported the only other patients in the literature with orbital pseudotumor at less than 3 years old. The clinical manifestations of this illness include orbital or periorbital edema, erythema, proptosis, palpable mass lesions, orbital congestion, ptosis, photophobia, tenderness, diplopia, and pain with ocular motility. Constitutional signs including headache, emesis, sore throat, anorexia, abdominal distress, lethargy, and weight loss were seen in 53% of pediatric patients studied by Mottow-Lippa et al. 6 These symptoms are rarely reported by adult patients. These authors also describe three distinguishing features in the pediatric population: (1) bilaterality is common, seen in 45% of their patients, but is rare in
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FI6.3. Biopsy specimen of orbital tissue in case 2 shows infiltration with dense fibrous connective tissue and chronic inflammatory infiltrate including numerous eosinophils. (Hematoxylin and eosin stain, original magnification x125.) TABLE. Neuroimaging features of orbital pseudotumor 1. Proptosis 2. Contrast enhancement and infiltration of orbital tissue 3. Extraecular muscle enlargement 4. Absence of contiguous paranasal sinus disease 5. Absence of bony erosion or distortion of orbital contents
FI6.2. A, Seventeen-month-old girl with erythema and edema of right upper eyelid. B, Magnetic resonance imaging scan documents extraconal mass involving right lacrimal gland. There is no evidence of bone destruction.
adults, (2) associated iritis occurs in 25% of children, usually indicates a poor prognosis, and may be the presenting sign of the disease, 7 and (3) trauma may precede the inflammatory process in children. 6 Additionally, peripheral eosinophilia is seen more commonly in the pediatric patient with orbital pseudotumor than in the adult patient. The etiology of pseudotumor of the orbit is unknown; however, there are three theories as to its pathogenesis. It is thought by some to be the result of an immune reaction because of the increased tendency of some of these children to develop autoimmune disorders in adulthood. 1 Circulating antibodies to extraocular muscle proteins have been found in some patients. There is also an association between orbital pseudotumor and preceding viral respiratory tract infections, suggesting an immune response to a viral or bacterial antigen. Others note that the histopathologic findings are similar to those of systemic fibrotic disorders. They postulate an aberrant immune-mediated production of fibrogenic cytokines such as transforming growth factor-J3 and platelet-derived growth factor, which
both lead to fibroblast proliferation and extracellular matrix deposition. 7 Pseudotumor of the orbit is often a diagnosis of exclusion, and therefore it is important to approach the evaluation with a thorough differential diagnosis. Other entities seen in infants and children include orbital cellulitis, thyroid ophthalmopathy, rhabdomyosarcoma, leukemia, histiocytosis, sinus mucocoele, dermoid cyst, and optic nerve glioma. Typically, laboratory studies in orbital pseudotumor are normal, with the exception of an elevated leukocyte count, an elevated erythrocyte sedimentation rate, and peripheral blood eosinophilia. 6 Laboratory studies will often result in values resembling values obtained in patients with periorbital or orbital cellulitis. Evaluation should always exclude an infectious cause for orbital inflammation. Orbital imaging will usually differentiate orbital pseudotumor from orbital cellulitis. Computed tomographic findings consistent with pseudotumor include presence of a diffuse orbital mass, uveoscleral thickening, contrast enhancement of Tenon's potential space, proptosis, and optic nerve and extraocular muscle enlargement. 8 Bone erosion or destruction is extremely rare in orbital pseudotumor, but it has been reported. 9 A helpful diagnostic point is the presence of concomitant sinusitis, usually seen with orbital cellulitis but rarely present in orbital pseudotumor. We recommend the following laboratory studies in the evaluation of a child with signs and symptoms of an orbital mass lesion: complete blood cell count with absolute
]ournal ofAAPOS Volume 2 Number 2 April 1998 eosinophil count, erythrocyte sedimentation rate, and thyroid function studies. Neuroimaging studies with either a computed tomographic or magnetic resonance scan are indicated in patients with suspected orbital pseudotumor. The imaging pattern reveals diagnostic findings outlined in the Table. Unlike the situation in orbital malignancies, bone erosion or destruction is rare. 7 Our cases were notable in that the inflammatory process occurred in a discrete area resembling a mass lesion, which is more common in the chronic sclerosing form of the disease. Histopathologically, pseudotumor of the orbit consists of nonspecific polyrnorphic lymphocytic infiltrates, with eosinophils, polymorphonuclear leukocytes, and macrophages. Increased connective tissue with edema and fibrosis is also commonly seen. Extensive fibrosis formation on the biopsy specimen is termed sclerosing orbital pseudotumor. Treatment with systemic corticosteroid therapy, 1.0 to 1.5 mg/kg/day in children, often gives symptomatic relief within 24 to 48 hours. Steroids are slowly tapered if the patient remains asymptomatic. Because of the rapid response to corticosteroid treatment, a trial dose of prednisone can be helpful in confirming the diagnosis. Orbital biopsy is recommended for cases suspicious for an orbital malignancy after evaluation with the imaging and serum studies that were mentioned above. Biopsy is also recommended when a poor or equivocal response to steroids is seen. 1° Low-dose irradiation is typically reserved for elderly patients who have lymphoid-type pseudotumor, are unresponsive to steroids, or in whom steroids are contraindicated.10 Surgical decompression is usually indicated only if medical management has failed, but it has recently been suggested as a good approach to patients with a focal or
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anteriorly located tumor. 7 T h e long-term prognosis is favorable, although a 30% recurrence rate is reported. ~ Recurrence is most commonly seen in patients with bilateral disease and iritis, and in severe cases residual proptosis and visual impairment may occur. We have described two patients with the development of orbital pseudotumor before age 18 months. Both of these children were initially treated for infectious conditions but eventually responded nicely to initiation of steroid therapy. These children emphasize the need to include pseudotumor in the differential diagnosis of orbital processes in infants and young children. References
1. Brown DH, MacRae DL, Allen LH. Orbital pseudotumors. J Otolaryngol 1988;17:4:164-8. 2. Blodi FC, Gass J. Inflammatory pseudotumor of the orbit. Br J Ophthalmol 1968;52:79-93. 3. Mot-towLS,JakobiecFA. Idiopathicinflammatoryorbital psendommor in childhood.Arch Ophthalmol 1978;96:1410-7. 4. Grossnildaus HE, Lass JH, Abramowsky CR, Levine MR. Childhood orbital pseudotumor.Ann Ophthalmol 1985;17:372-7. 5. BergerJW,RubinPAD,JakobieeFA. Pediatricorbitalpseudotumor: case report and review of the literature. Int Ophthalmol Clin 1996;30:161-77. 6. Mottow-LippaL, Jakobiec FA, Smith M. Idiopathicinflammatory orbital pseudotumor in childhood. Ophthalmology 1981;88:6: 565-74. 7. MombaertsIL, GoldschmedingR, SchlingemannRO, KoorneefL. What is orbital pseudotumor?Surv Ophthalmol 1996;41:66-78. 8. BloomJN, Graviss ER, Byrne BJ. Orbital pseudotumorin the differential diagnosis of pediatric uveitis. J Pediatr Ophthalmol Strabismus 1992;29:1:59-63. 9. Flanders AE, Mafee Mr, Rao VM, Choi KH. Characteristics of orbital pseudotumors and other orbital inflammatoryprocesses.J Comput AssistTomogr 1989;13:40-7. 10. MaurielloJA, FlanaganJC. Managementof orbital inflammatory disease: a protocol. Surv Ophthalmol 1984;29:104-16.