Hypertrophic pachymeningitis is a condition where there is localized inflammatory thickening of the dura. On imaging, it presents as a localized, multiple, or diffuse enhancing dural thickening commonly forming mass-like lesions.
Can have a multitude of presentations. Cranial nerve palsies are common.
It can result from a number of causes which include:
When no cause is identified it is termed idiopathic hypertrophic pachymeningitis.
- shows localized, or less often, diffuse dural thickening
- at times can depict mass-like thickening when it is termed tumefactive hypertrophic pachymeningitis
Signal characteristics include:
- T1: thickened areas are hypointense to brain parenchyma on unenhanced T1 images
- T1 C+ (Gd): shows dural enhancement
- T2: thickened areas are hypointense to brain parenchyma
General imaging differential considerations include:
- meningeal metastases
- meningeal involvement with CNS lymphoma
- multiple meningiomas including lymphoplasmacyte-rich meningioma
- intracranial involvement with Erdheim Chester disease
- Polyarteriitis nodosa
- Rheumatoide Arthritis
- dural enhancement
- Granulomatose mit Polyangiitis
- Tuberkulose des ZNS
- tuberculous pachymeningitis
- zerebrale Kryptokokkose
- zerebrales Lymphom
- idiopathische hypertrophe Pachymeningitis