IDIOPATHIC CRANIAL PACHYMENINGOENCEPHALITIS FOCALLY AFFECTING THE PARIETAL DURA-MATER AND ADJACENT BRAIN PARENCHYMA - CASE-REPORT

OBJECTIVE AND IMPORTANCE: Cranial pachymeningitis is a typically diffu se granulomatous disease, which often affects the tentorium and fair. We report a rare case of idiopathic cranial pachymeningoencephalitis f ocally affecting only the left parietal dura mater and adjacent inferi or parietal lobule. CLINICAL PRESENTATION: A 46-year-old woman, with n o history of disease, suddenly had a generalized convulsion. A gadolin ium-enhanced T1-weighted magnetic resonance image showed homogeneously stained meninges extending to the cortical parenchyma with marked per ifocal edema. The thickened dura was visualized as a hypointense area on a T2-weighted magnetic resonance image. INTERVENTION: The patient u nderwent successful en bloc excision of the mass involving the dura ma ter and adjacent brain parenchyma. Histological examination of the dur a mater revealed large numbers of chronic and acute inflammatory cells . These cells were also present in the subarachnoid and Virchow-Robin spaces and part of the brain parenchyma in the resected cortex. After the operation, the patient experienced no neurological deficits or rec urrent mass for 10 months. CONCLUSION: Early diagnosis of pachymeningi tis using magnetic resonance imaging is important for the treatment of pachymeningoencephalitis, because diffuse involvement of the dura mat er and brain parenchyma can make en bloc excision difficult.