title: Idiopathic hypertrophic cranial pachymeningitis misdiagnosed as acute subtentorial hematoma.
abstract: A case of idiopathic hypertrophic cranial pachymeningitis (IHCP) misdiagnosed as an acute subdural hematoma is reported. A 37-year-old male patient presented with headache following head trauma 2 weeks earlier. Computerized tomography showed a diffuse high-density lesion along the left tentorium and falx cerebri. Initial chest X-rays revealed a small mass in the right upper lobe with right lower pleural thickening, which suggested lung cancer, such as an adenoma or mediastinal metastasis. During conservative treatment under the diagnosis of a subdural hematoma, left cranial nerve palsies were developed (3rd and 6th), followed by scleritis and uveitis involving both eyes. Magnetic resonance imaging (MRI) revealed an unusual tentorium-falx enhancement on gadolinium-enhanced T1-weighted images. Non-specific chronic inflammation of the pachymeninges was noticed on histopathologic examination following an open biopsy. Systemic steroid treatment was initiated, resulting in dramatic improvement of symptoms. A follow-up brain MRI showed total resolution of the lesion 2 months after steroid treatment. IHCP should be included in the differential diagnosis of subtentorial-enhancing lesions.
authors.affiliation: Department of Neurosurgery, St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Bucheon, Korea.
authors.forename: Ik-Seong
authors.initials: IS
authors.lastname: Park
authors.forename: Hoon
authors.initials: H
authors.lastname: Kim
authors.forename: Eun Yong
authors.initials: EY
authors.lastname: Chung
authors.forename: Kwang Wook
authors.initials: KW
authors.lastname: Cho