This gentleman had a right hemi-thyroidectomy done 10 years ago for a thyroid mass. HPE could not be ascertain. His present ultrasound showed there is no normal thyroid on the right side of the neck (top image) but the left lobe has hypertrohied with even retro-sternal extension (middle image). In addition, the left lobe is also showing changes consistent with multi-nodular goitre (lower image).
Interestingly, in our body there are a number of organs that will hypertrophy (become enlarged) when one part of it or the contra-lateral part is removed or dysfunctional. Examples are kidney, liver, spleen and lung.
Unfortunately, our brain doesn't do that. I wish it is!