Undescended thymus

Possible abnormalities that can be observed include retroesophageal aortic arch, ventricular septal defects, and partially undescended thymus. 

There are many other abnormalities that can be identified in these sections, ranging from abnormalities considered as malformations (e.g., microphthalmia) through to minor abnormalities (e.g., partially undescended thymus). 

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