Learning objectives
Be familiar with the different thymus gland appearances in Chest X Ray
What to do next if mediastinal mass is suspected
Characteristics of normal thymus tissue on ultrasound
Background
The thymus is a lymphatic organ located in the antero-superior mediastinum.
When sizeable,
it consist of two lateral lobes touching in the midline,
situated partly in the thorax,
partly in the neck.The two lobes are usually asymmetric in size.
They are occasionally united,
so as to form a single mass.
Sometimes they are separated by an intermediate lobe.
The gland extends from as high as the lower border of the thyroid glandto the fourth costal cartilage downwards.
It originates from the third and fourth branchial...
Findings and procedure details
Conventional radiography:
The thymus is variable in size and position and The appearance of the thymus on frontal chest radiographs is variable and largely dependent on the age of the patient.
It may mimic cardiomegaly,
abnormally positioned vessels,
pericardial fluid,
or a mediastinal mass.
The normal thymus has a soft tissue density and smooth borders.
The thymus is prominent in size with a quadrilateral shape and convex margins during infancy.
After approximately the fifth year of life,
the
thymus becomes more triangular in shape with...
Conclusion
It is important for clinicians to be able to identify normal variations in thymic appearance and avoid over-investigation.
It is important to be familiar with different appearances in the normal thymus gland to be able to identify pathology and make an accurate diagnosis.
Personal information
Dr Nehal Mohamed Saloum.
Clinical Fellow,
Diagnostic Imaging.
Hamad Medical Corporation,
Doha,
Qatar.
Email:
[email protected].
References
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Imaging of the pediatric thymus: Clinicoradiologic approach.
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2017; 8;10-23.
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Caffey's Pediatric Diagnostic Imaging ‘Twelfth Edition’.
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et al.
The thymus: a comprehensive review.
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The thymus: from past misconception to present recognition.
Pediatr Radiol.
1998; 28: 275–282.
5) Slovis TL,
et al.
Aberrant thymus: MR assessment.
Pediatr Radiol 1992; 22:490–492.
6) Steinmann GG.
Changes in the human thymus during aging.
Curr...