title: Infrequent bilateral orbital tumors and simulating lesions: the experience of a Chinese institute.
abstract: OBJECTIVE
  To determine the types, frequency, and clinical features of infrequent bilateral orbital lesions.
  
  
  METHODS
  We reviewed 41 cases of either histopathologically or radiologically verified bilateral orbital lesions. The number and entities in each category were recorded. Clinical data and imaging findings were reviewed.
  
  
  RESULTS
  The number and percentage of lesions in each general category were leukemia lesions in eight patients (19.5%), metastatic tumors in seven (17%), optic nerve and meningeal tumors in six (14.6%), secondary tumors in six (14.6%), peripheral nerve lesions in four (9.8%), inflammatory lesions in four (9.8%), and vasculogenic, histiocytic, and miscellaneous lesions, each in two patients (4.9%). These lesions occurred in both childhood and adulthood, but were infrequent in people over 60 years old. Of all cases, 51.2% were benign and 48.8% were malignant. The ocular symptoms and signs presented unilaterally in 18 (43.9%) cases and bilaterally in 23 (56.1%). Of the 15 patients with either metastatic tumors or blood disorders, two (13.3%) had a history of primary neoplasm at presentation. In 19 (46.3%) cases, the configuration of the bilateral lesions was symmetrical, and they were of equal size. Computed tomography scans revealed bone changes in 13 patients (31.7%), while magnetic resonance imaging revealed intracranial extension in nine (22%).
  
  
  CONCLUSIONS
  Varied lesions can involve the bilateral orbits simultaneously or on follow-up. Through the combination of history, bilateral ocular manifestations, radiologic findings, and systemic examinations, the correct diagnosis can be made, which is valuable for early identification of both metastasis and blood disorders.
authors.affiliation: Institute of Orbital Diseases, Armed Police General Hospital, Beijing, China. yieye@sina.com.|Institute of Orbital Diseases, Armed Police General Hospital, No.69 Yongding Road, Haidian District, Beijing, China. yieye@sina.com.
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Orbital Diseases, Armed Police General Hospital, Beijing, China.
authors.forename: Li
authors.initials: L
authors.lastname: Kang
authors.affiliation: Institute of Orbital Diseases, Armed Police General Hospital, Beijing, China.
authors.forename: LiHua
authors.initials: L
authors.lastname: Xiao
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D015994:Incidence; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009918:Orbital Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology; D017678:Sex Distribution; D014057:Tomography, X-Ray Computed