title: Thyroid hemiagenesis: a case series and review of the literature.
abstract: OBJECTIVE
  The purpose of this study is to present a case series and review recommendations within the literature concerning thyroid hemiagenesis.
  
  
  METHODS
  This is a (1) retrospective case series review of 5 patients and (2) literature review (using Medline) on thyroid hemiagenesis.
  
  
  RESULTS
  Most reported cases are female with the left thyroid lobe absent. Compensatory hypertrophy occurs in most thyroid remnants. Associated diagnoses in the remaining lobe include hyperthyroidism, hypothyroidism, simple and multinodular goiter, and carcinoma. There is no increased risk for the subsequent development of cancer in the remaining lobe, and empiric thyroidectomy is not justified.
  
  
  CONCLUSIONS
  Thyroid hemiagenesis is an uncommon presentation that is frequently asymptomatic and detected incidentally when imaging for another condition. Awareness of its existence can help prevent unnecessary interventions associated with incorrect assumptions in patient care.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Tufts Medical Center, Boston, MA 02111, USA. YWu@tuftsmedicalcenter.org
authors.forename: Yi-Hsuan Emmy
authors.initials: YH
authors.lastname: Wu
authors.forename: Richard O
authors.initials: RO
authors.lastname: Wein
authors.forename: Barbara
authors.initials: B
authors.lastname: Carter
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013959:Thyroid Diseases / Q000151:congenital* / Q000000981:diagnostic imaging; D013961:Thyroid Gland / Q000002:abnormalities* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed