Adrenal gland

What it means

There are two of these glands in the body, one perched like a cap on top of each kidney. They are small — roughly the size of a walnut — but they punch above their weight. They make cortisol (a stress hormone), aldosterone (which controls salt and blood pressure), small amounts of sex hormones, and adrenaline. On a CT or MRI scan they appear as thin, inverted V-shaped or Y-shaped structures sitting above each kidney in the upper belly.

Why it appears on a CT or MRI report

Radiologists name these glands when they look anything other than thin and smooth. The most common reason is a small nodule found by chance on a scan ordered for something unrelated — often called an incidentaloma. Reports describe the side, the size in millimetres, the shape, the density (in Hounsfield units on CT) or the signal pattern (on MRI), and whether the nodule looks fatty or solid. Each of those features helps tell a benign nodule apart from one that needs more attention.

What it usually means

An incidental nodule here is one of the most common findings in modern imaging — somewhere around one in twenty adults has one, and that number rises with age. The reassuring news is that the vast majority are benign, non-functioning nodules called adenomas. Two features point strongly toward benign: small size (under about 4 cm) and a low-density, fat-containing appearance on CT. Follow-up often involves a small set of hormone blood tests to check the nodule is not quietly making extra hormones, and sometimes a repeat scan in 6 to 12 months to confirm it is stable. A small minority of nodules need closer evaluation because they are larger, look denser, grow over time, or produce hormones — in which case a hormone specialist (endocrinologist) usually takes over the conversation.

When to follow up

If the report mentions a nodule, expect a routine follow-up rather than an emergency. Talk to your doctor about the size, the density value, and whether a few simple hormone tests are appropriate. Symptoms worth mentioning include hard-to-control high blood pressure, unexplained weight gain around the trunk with thin limbs, easy bruising, muscle weakness, episodes of palpitations with sweating, or unusually low potassium on a previous blood test. A nodule with none of those features and a benign appearance often needs nothing beyond a check-in.

A plain-language way to picture it

Picture each kidney as a kidney-shaped bean lying in the back of the belly, with a small triangular hat resting on top of it. That hat is one of these glands. It is tiny but acts as the body's stress and salt control room. A small lump on the hat is a bit like a felt patch sewn on — usually decorative and harmless, occasionally something the tailor wants to inspect more closely before deciding what, if anything, to do about it.