General information

An involvement of the skull bones is usually first noticed by a deformation or increase in size of the skull, since this becomes visible on the head quite early due to the lack of fat and connective tissue. Patients report, for example, that hats or helmets no longer fit them properly.

X-ray

If there is a suspicion that the bones of the skull are affected by Paget’s disease, an X-ray of the skull is usually taken first. In the early stages of the disease, focal oval brightening is visible, indicating the onset of bone loss (osteolysis). Later, due to the “repair attempts” of the bone-building cells (osteoblasts), an excessive production of bone substance is added, which is shown in the x-ray by a widening of the skull bones with an irregular bone structure (“cotton skull”). The changes usually begin in the area of the frontal and occipital bone and may spread to the temporal bone in the further course (osteolysis circumscripta cranii). Fractures of the skull, which can occur as a result of bone resorption in the course of the disease, can also become visible in the X-ray image.

Scintigraphy

However, an X-ray of the skull should not be taken as a standard procedure in every patient with Paget’s disease, but only if there is evidence that the skull is affected. Except when symptoms occur, this is also the case, for example, when a scintigraphy is performed as part of the initial diagnosis, in which an accumulation of the radioactively marked substance in the area of the head is noticeable. This allows the conclusion to be drawn that there is increased metabolic activity in the cranial bones, which is typical for an infestation with Paget’s disease.

CT and MRT

For this reason, a Paget’s disease of the skull should be accompanied by a neurological examination and a hearing test, because in 30 to 50 percent of cases, hearing loss occurs due to a narrowing of the auditory nerve or damage to the ossicles. Damage to the optic nerve or other cranial nerves is less common, but should still be excluded.