TABLE 1:
Scheme for the evaluation of cranial MR images in patients with LCH
| Anatomic Structure | Changes |
|---|---|
| Craniofacial bones and skull base | Bone destruction, tumorous infiltration, intracranial extension |
| Paranasal sinuses | |
| Ethmoidal | Bone destruction |
| Maxillar | Opacification (fluid intense, tissue intense) |
| Sphenoidal | Enhancement |
| Intracranial and extra-axial | |
| Meninges | |
| Epidural | With or without bone destruction |
| Subdural | Infiltration, enhancement, symmetry |
| Circumventricular organs* | Enlargement, cystic formation, enhancement, symmetry |
| Hypothalamic-pituitary region | |
| Anterior pituitary | Size (empty sella, atrophy, normal, enlarged), symmetry, enhancement |
| Posterior pituitary | Size, T1WI hyperintensity present or absent |
| Infundibulum | Size (measured in at least 2 planes) normal, thickened >2.6 mm, cranial-caudal different, threadlike <1 mm |
| Hypothalamus | Mass lesions, enhancement |
| Intracranial and intra-axial, parenchymal | |
| WM | |
| Vascular pattern | Symmetry |
| VRSs on T2WI† | Enhancement, space-occupying effect, edema |
| Perivascular spaces | Visibility on T2WI |
| Brainstem, pons | Leukoencephalopathy-like pattern |
| Cerebellar WM enhancement | T2WI hyperintensity, T1WI isointensity or hypointensity, not space-occupying |
| GM | |
| Basal ganglia | T1WI hyperintensity or hypointensity |
| Cerebellar dentate nuclei | T2WI isointensity, hypointensity, or hyperintensity |
| Atrophy | Localized, diffuse |
*
Pineal gland, ependyma, choroid plexus.
†
VRS indicates Virchow-Robin space.