Calvarial Thickening in Tuberous Sclerosis Complex

Abstract

Background: Tuberous sclerosis complex (TSC)-related skeletal abnormalities are understudied. Awareness of skull thickening in patients with TSC is important from the surgical standpoint because a thick skull might complicate craniotomy. This study aimed to discover if patients with TSC are generally prone to skull thickening by retrospectively investigating the frequency and characteristics of skull thickening in these patients.

Methods: Patients with TSC ages 10 to 60 years who underwent magnetic resonance imaging in the neurosurgery, dermatology, or pediatrics clinic between 2010 and 2021 were identified. Two control groups were used for comparison: one with patients with unruptured intracranial aneurysms to serve as control without antiseizure medication exposure and one with non-TSC epilepsy as control with antiseizure medication exposure. In all patients, thickness of frontal, parietal, temporal, and occipital bones was measured at a fixed location of each bone on T2-weighted axial images.

Results: Inclusion criteria were fulfilled by 29 patients. Frontal and temporal bones of the TSC group were significantly thicker than those of either control group. Skull thickening was significantly associated with intracerebral calcification, but not with age, sex, or antiseizure medication exposure. Focal skull thickening was associated with the presence of a subcortical calcification.

Conclusions: Patients with TSC have skull thickening, which is often linked to intracerebral calcification. The presence of skull thickening may require modification of surgical approach during craniotomy. Skull thickening and the underlying intracerebral calcification likely share a common precipitating factor given their relationship. Future studies are warranted to clarify the genetic underpinnings of this relationship and even broader skeletal abnormalities in TSC.

Keywords: Craniotomy; Skull thickening; Tuberous sclerosis complex.