Questions What is the diagnosis ? How do you manage ?
Introduction SSG First described by Haller in 1749. Account for 10-15% of all the mediastinal mass. SSG / All thyroidectomy = 2.6-20% Madjar Chest 1995
Definition Confused. 1.Decend inferior to the thoracic inlet. Katlic et al Am J Surg 1998 2. >50% thyroid mass inside the thorax. Wax et al J Otolaryngol 1992 Arici et al Int Surg 2001 3.Goitres extend to 4th thoracic vertebra. Lindskog and Goldenberg JAMA 1957
Anatomy SSG classified into two groups. 1.Truly intrathoracic or aberrant goiter (1%). Congenital Blood supply derived from the intrathoracic vessel entirely. No connection to the cervical thyroid gland. Lahey & Swinton et al 1934
Anatomy 2. Arises in the cervical thyroid gland Acquired. Decends along a fascial plane through the thoracic inlet to the mediastinum. Lahey & Swinton et al 1934
Symptomatology Neck mass, SOB, dysphagia. 5-50% can be asymptomatic on presentation. Katlic MR Am J Surg 1985 Prolong course of symptoms. From 2 weeks to 20 years with symptoms before referral. Mean = 31 months.
Rationale for operation 1. SSG is progressive, can result in sudden airway obstruction. Singh B Am J Otolaryngol 1994. 2. Inaccessible to, inaccurate, and dangerous biopsy. Rietz KA Acta Chir Scand 1960 3. Long history MNG does not preclude malignancy, hyperfunction or complication. Malignancy in 7-17% Sanders Arch Surg 1992 Torre G Am Surg 1995
Rationale for operation 4.No effective alternative treatment. I131? T4? Allo MD Surgery 1983 5.Less operative complication in the asymptomatic patients. Para-Menbrives et al Internat Surg 2003 The consensus is that substernal goiter is best managed surgically. Katlic MR Am J Surg 1985
Investigation CT neck and thorax is the most valuable. Netterville et tal Laryngoscope 1998 Sanders LE Arch Surg 1992 1.Outline the extent of thyromegaly. 2.Differentiate the origin of the goiter. 3.Measure the degree of narrowing of the trachea.
The operation 1.Head up, neck well extended. 2.Wider and lower incision. 3.Division of the strap muscles. 4.Control cervical blood supply first. 5.Excise the opposite lobe first, to provide more room in the neck. Wheeler M.H. et al BJS 1999 Sternotomy rate 2-11.7 % Michel LA Br J Surg 1988
The operation No Progress ManubrinectomyClaviclectomy Median sternotomy/ Limited sternotomy