RT Book, Section
A1 Mekel, Michal
A1 Hodin, Richard A.
A2 Morita, Shane Y.
A2 Dackiw, Alan P. B.
A2 Zeiger, Martha A.
SR Print(0)
ID 6162090
T1 Chapter 2. Goiter
T2 McGraw-Hill Manual: Endocrine Surgery
YR 2010
FD 2010
PB The McGraw-Hill Companies
PP New York, NY
SN 978-0-07-160645-5
LK accesssurgery.mhmedical.com/content.aspx?aid=6162090
RD 2024/04/23
AB Goiter  is  defined  as  enlargement  of  the  thyroid  gland.  It  generally  results  from  focal  follicular  cell  hyperplasia  at  one  or  multiple  sites  within  the  thyroid  gland,  and  it  usually  develops  over  years.  Endemic  goiter  refers  to  enlargement  of  the  thyroid  gland  secondary  to  iodine  deficiency  affecting  more  than  10%  of  the  population  in  a  defined  geographic  area.  Sporadic  goiter  develops  in  subjects  living  in  iodine-sufficient  areas.  Goiter  encompasses  a  spectrum  of  entities,  including  diffuse,  uninodular,  or  multinodular  enlargement  of  the  thyroid  gland.  The  overall  hormonal  status  of  the  thyroid  nodules  within  the  goiter  determines  the  function  of  the  gland  and  the  definition.  When  enlargement  of  the  thyroid  gland  is  present  without  clinical  or  laboratory  evidence  of  thyroid  dysfunction,  it  is  euthyroid  multinodular  goiter  (MNG);  when  accompanied  by  hyperthyroidism,  it  is  toxic  nodular  goiter  (TNG).  Less  frequently,  thyroid  enlargement  is  caused  by  two  other  disorders  such  as  fibrous  chronic  Hashimoto's  thyroiditis,  Graves'  disease,  or  neoplasia.  Retrosternal  or  substernal  goiter  refers  to  goiter  that  is  associated  with  extension  into  the  mediastinum.