There are three types of retrosternal goiters (RGs): 1) primary intra-thoracic goiters that arise from aberrant thyroid tissue in the mediastinum, 2) secondary RGs that develop from downward migration of the thyroid gland into the mediastinum, and 3) plunging goiters that rise and fall through the thoracic inlet. Secondary RGs are most common and are connected to the cervical thyroid, receiving blood supply from cervical vessels. Symptoms include dyspnea that is worsened by positions reducing the thoracic inlet, and sometimes dysphagia. Thyroidectomy is the treatment, performed via cervical approach but sometimes requiring median sternotomy.

2.  a goitre with a portion of its mass located in the
mediastinum

3.  Primary intra-thoracic goitres arise from aberrant thyroid
tissue which is ectopically located in the mediastinum,
receive their blood supply from mediastinal vessels and are
not connected to the cervical thyroid. They are rare,
representing less than 1% of all RGs
 Secondary RGs develop from the thyroid located in its
normal cervical site. Downward migration of the thyroid
into the mediastinum is facilitated by negative intra-thoracic
pressure, gravity, traction forces during swallowing and the
presence of anatomical barriers preventing the enlargement
in other directions (thyroid cartilage, vertebral bodies, strap
muscles, especially in patients with a short, large neck).
These secondary RGs are, characteristically, in continuity
with the cervical portion of the gland and receive their
blood supply, depending on cervical vessels, almost always
through branches of the inferior thyroid artery.

4.  Plunging goiter : rise with deglutition and then
descent again through the thoracic inlet
 Mediastinal goiter : lie wholly in the chest but
are connected with the thyroid and supplied by
thyroid vessels through narrow band
 Intrathracic goiter : lie wholly in the chest but
completely separated from the gland supplied
by mediastinal vessels

5.  Short-necked individuals
 Usually after middle age
 Intrathracic goiter more common in men

6.  May remain symptomless for years
 Dyspnea due to displacing and compressing on
the trachea
 The Dyspnea aggravated by any posture that
reduces the thoracic inlet as lying down or
flexion the neck
 The patient prefer to spend the night in a chair
 Some time they miss diagnosed as asthmatic
 Sometimes there is dysphagia

7.  Inspection

8.  Palpation : thyroid gland enlarged

9.  Percussion of the sternum may reveal
retrosternal dullness

10.  X-ray

11.  X-ray

12.  CT

13.  CT

14.  CT

15.  Tc99m

16.  Fiberscope

17.  Thyroidectomy is the only line of treatment
 Mostly via cervical approach , rarely a median
sternotmy is required
 Devascularization is done via the neck from
which the retrosternal portion derived its blood
supply
 Special care should be exerted to avoid injury
of the recurrent laryngeal nerves during the
delivery of retrosternal goter