title: Medial canthal tophus associated with gout.
abstract: OBJECTIVE
  To report a case with a gouty tophus at the medial canthus.
  
  
  METHODS
  Observational case report.
  
  
  METHODS
  Review of the clinical, laboratory, photographic, and pathologic records of a patient with a gouty tophus at the medial canthus.
  
  
  RESULTS
  A 27-year-old man had a 3-year history of gouty arthritis and poorly controlled hyperuricemia. A medial canthal mass without discomfort developed gradually over 3 months. An excisional biopsy was performed, and the tissue was fixed in formalin for pathology. Analysis of a routine hematoxylin-and-eosin-stained section disclosed a multilobulated pseudocyst filled with amorphous eosinophilic material. Further staining with nonaqueous alcoholic eosin and viewed under a polarizing microscope indicated the presence of birefringent urate crystals.
  
  
  CONCLUSIONS
  Gouty tophus can develop progressively at the medial canthus, especially in people with uncontrolled hyperuricemia. A formalin-fixed specimen, stained with nonaqueous alcoholic eosin, demonstrates abundant birefringent urate crystals under a polarizing microscope.
authors.affiliation: Department of Ophthalmology, Chang Gung Memorial Hospital, No. 5 Fu-Hsin Street, Kwei-Shan Shiang, Taoyuan, Taiwan.
authors.forename: Yen Chang
authors.initials: YC
authors.lastname: Chu
authors.forename: Yi Yueh
authors.initials: YY
authors.lastname: Hsieh
authors.forename: Lih
authors.initials: L
authors.lastname: Ma
mesh_terms: D000328:Adult; D015210:Arthritis, Gouty / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D001718:Birefringence; D005141:Eyelid Diseases / Q000150:complications* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008297:Male; D014527:Uric Acid / Q000097:blood
chemical_list: D014527:Uric Acid