Lobulated Heterogeneous Thyroid
Let’s start with discussing what a Lobulated heterogeneous thyroid means.
Lobe is defined as any of the main divisions of an organ separated by fissures, e.g. a lobe of the brain, lung, or liver. So lobes are small, mostly rounded, divided compartments of any organ. Lobules are further subdivisions of lobes. Hence lobulated appearance of thyroid on ultrasound implies a thyroid surface with multiple, rounded and small projections.
Normal thyroid is Homogeneous in texture. It has two lobes, one on right and the other on the left side. There’s a band of normal thyroid tissue connecting the two. This band is called the isthmus.
Heterogeneous means that thyroid appears to be composed of unrelated or varied elements. For example; heterogeneous areas of fibrosis, cysts, hemorrhage, necrosis etc.
It is not normal for a thyroid to show heterogeneity. However, as we age up, some areas of the gland may become necrosed or fibrosed. That’s normal.
In general, a Heterogenous thyroid needs to be investigated further. Some areas of the gland may be inflamed, as is Thyroiditis, There may be nodules in there, which may be toxic or non toxic.
It’s difficult to comment upon the exact nature of the disease, solely on the basis of ultrasonographic appearance. The diagnosis typically requires microscopic examination of thyroid tissue, obtained through biopsy. Clinical correlation is done to make the diagnosis. But heterogeneous areas may sometimes be seen with various tumors.
Ultrasound Findings Common With Malignancy
Presence of solitary nodes drives more attention towards investigation. Multiple nodules are usually seen in benign states, though exceptions may be seen in papillary carcinomas of the thyroid.
Whether the node is Solid or Cystic- Cystic nodes, in general, point towards benignity. They develop when a focal area of the gland suffered hemorrhage or undergoes a cystic degenerative change. Solid nodules need to be investigated cautiously.
If calcified, the pattern of calcification needs to be studied carefully. A fine microcalcification or a ‘punctate’ calcification may imply malignancy. While, coarse calcification, especially along the margins of the lesion are mostly benign.
Margins of the lesion being observed needs to be studied. Irregular margins, showing a halo around them calls for malignant change.
Classic “Comet tail” appearing lesions of thyroid tissue are considered benign.