hypertrophic pachymeningitis

Dural masses:

meningiomas and their mimics. IgG4-related hypertrophic pachymeningitis with skull invasion. a Post-contrast coronal T1-weighted MR image showing linear dural thickening and enhancement overlying the left cerebral convexity. Note that the overlying calvarial bone marrow signal is abnormal. b Apparent diffusion coefficient (ADC) map showing restricted diffusion in the lesion overlying the left parietal region. c Post-contrast axial T1-weighted image of the same lesion with enhancing soft tissue seen invading the skull. d Axial fluid attenuated inversion recovery (FLAIR) image showing the lesion is predominantly hypointense due to fibrosis with foci of hyperintensity

insightsimaging.springeropen.com • CC-by-4.0

Anti-NMDAR

encephalitis with simultaneous hypertrophic pachymeningitis in a 68-year-old male: a rare case report. Magnetic resonance imaging of the brain: a thickening of dura mater localized at the left tentorium cerebelli, left cerebral hemisphere, and cerebral falx; the thickening dura mater was characterized by an intense contrast enhancement after the administration of gadolinium (a, b). Magnetic resonance venography: no obvious indication of the left internal jugular vein, and both of the left transverse sinus and the sigmoid sinus was slim with local stenosis; there was also increased cortical drainage in the left cerebral hemisphere (c)

bmcneurol.biomedcentral.com • CC-by-4.0

Hypertrophic

pachymeningitis • Hypertrophic pachymeningitis - Ganzer Fall bei Radiopaedia

Balachandran G, Hypertrophic pachymeningitis. Case study, Radiopaedia.org (Accessed on 03 Dec 2022) https://doi.org/10.53347/rID-10821 • CC by-nc-sa 3.0 (modified)

Hypertrophic

pachymeningitis • Pachymeningitis - Ganzer Fall bei Radiopaedia

Gaillard F, Pachymeningitis. Case study, Radiopaedia.org (Accessed on 03 Dec 2022) https://doi.org/10.53347/rID-43392 • CC by-nc-sa 3.0 (modified)

Radiopaedia • CC-by-nc-sa 3.0 • de

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.

Clinical presentation

Can have a multitude of presentations. Cranial nerve palsies are common.

Pathology

Etiology

It can result from a number of causes which include:

infective
inflammatory
- IgG4-related hypertrophic pachymeningitis
- granulomatosis with polyangiitis
- polyarteritis nodosa
- rheumatoid arthritis: rheumatoid pachymeningitis
neurosarcoidosis
haemodialysis
mucopolysaccharidoses

When no cause is identified it is termed idiopathic hypertrophic pachymeningitis.

Radiographic features

MRI

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