Learning objectives
To present and illustrate the thymic CT morphology in relation to age.
To list and discuss the CT features in thymic pathology.
To review the classification of thymic epithelial tumors.
To discuss the differential diagnosis of anterior mediastinal masses.
Background
Thymic function,
embryology,
histology and anatomy
The thymus is a central lymphoid organ that plays an important role in the maturation of the immune system,
especially regarding the cellular immunity during childhood [1].
The thymus arises in the sixth gestational week from the third and fourth branchial pouches and undergoes a descensus process towards its final location,
in the anterior mediastinum,
behind the sternum and anterior to the pericardium and great vessels,
and may extend longitudinally from the lower pole of the thyroid gland to...
Findings and procedure details
A retrospective study of 15 years including 180 patients,
aged 1- 80 years who have undergone a thoracic CT exam,
performed without and with contrast injection,
followed by MPR reconstructions in coronal and sagittal plane,
for suspicion of anterior mediastinal masses or in the context of myasthenia gravis/ myasteniformsyndrome.
In the current study,
60 patients had normal thymic features,
whilst 120 patients presented with anterior mediastinal masses.
The dominant pathologies were lymphoma and thymoma.
NORMAL THYMUS
Normal CT features of the thymus gland
The thymus...
Conclusion
In the context of continuously changing thymic morphology,
it is important to be familiar with its normal CT aspects.
Its shape is quadrilateral/ triangular with convex lateral borders before puberty and triangular with straight or concave lateral borders after puberty.
The size and density of the gland decrease with age.
The main differential diagnosis of masses involving the anterior mediastinum may be summarized by the mnemonic “4T”: thymoma,
teratoma,
thyroid tumors/ goiter and terrible lymphoma.
Whilst some of the anterior mediastinal masses may be diagnosed...
Personal information
Dr.Adriana Selea
mail:
[email protected]
Prof.Dr.Ioana G.Lupescu
mail:
[email protected]
Radiology,
Medical Imaging and Interventional Radiology,
Fundeni Clinical Institute,
UMPh Carol Davila,
Bucharest,
Romania
References
[1].Smita Manchanda,Ashu S Bhalla,Manisha Jana,
et al.Imaging of the pediatric thymus: Clinicoradiologic approach,World Journal of Clinical Pediatrics2017,
6(1): 10-23;
[2].Farbod Nasseri,Farzin Eftekhari,Clinical and Radiologic Review of the Normal and Abnormal Thymus: Pearls and Pitffals,RadioGraphics2010,
30:413-428;
[3].Mizuki Nishino,
Simon K.
Ashiku,Olivier N.
Kocher, et al.The Thymus: A comprehensive Review,RadioGraphics2006,
26: 335-348;
[4].Said Fadi Yassin,Surgery of Thymus Gland,Medscape2018;
[5].Mark Hill,SH Lecture- Lymphatic Structures and Organs,Embryology 2018;
[6].C.
Schaefer,
M.
Prokop,Mediastinum,
Pleura and Chest Wall,Spiral and Multislice Computed Tomography of the Body2003: 374-385;
[7].Koji Takahashi,Nabaa Jaba Al-Janabi,Computed Tomography...