title: Distribution of mediastinal ectopic thymic tissue in patients without thymic disease.
abstract: BACKGROUND
  Different approaches to treat myasthenia gravis showed variable outcomes probably because of remained ectopic thymic tissue. The aim of this study is to determine incidence of thymic tissue in cases without any thymic disease.
  
  
  METHODS
  Seventy-two patients scheduled for open heart surgery during 2000 and 2007 without thymic disease that were enrolled in the study at Chamran Hospital. Intraoperative biopsies were taken form aortopulmonary window, aortocaval groove and left and right pericardiophrenic regions. Finally, the distribution of ectopic thymic tissue was evaluated in above regions.
  
  
  RESULTS
  Thymic tissue was found overall in 70.85% of patients. The most common sites for thymic tissue were left pericardiophrenic (50%) and right pericardiophrenic (31.9%) regions. Frequencies of ectopic thymus in aortopulmonary window and aortocaval groove were 19.4% and 12.5%, respectively.
  
  
  CONCLUSIONS
  Because of high incidence of ectopic thymic tissue in mediastinum in patients without thymic disease, we recommend wide excision of thymus gland and all of adipose tissue in patients with myasthenia gravis.
authors.affiliation: Department of General Surgery, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Behnam
authors.initials: B
authors.lastname: Sanei
authors.affiliation: Department of General Surgery, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Seid Abbas
authors.initials: SA
authors.lastname: Tabatabie
authors.affiliation: Department of General Surgery, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hamid
authors.initials: H
authors.lastname: Bigdelian
authors.affiliation: Department of General Surgery, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Seid Mozafar
authors.initials: SM
authors.lastname: Hashemi
authors.affiliation: Department of General Surgery, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Amir Hossein
authors.initials: AH
authors.lastname: Davarpanah
authors.affiliation: Medical Student Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Jafari
authors.affiliation: Department of Pathology, Acquired Immunodeficiency Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Sanei
keywords: Ectopic thymic tissue; mediastinum; myasthenia gravis