The differentiation of a small echonormal intact lobe from a remnant after total lobectomy
A thyroid after total lobectomy. An operated thyroid - Case 2
A small echonormal lobe in an intact thyroid. Benign hyperplastic nodules - Case 7
   
   

The most important difference is that in contrast with the resected thyroid, the intact lobe is not trunctated at the isthmic part. See the difference marked with red arrows in horizontal while with green arrows in longidudinal images.
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