This study investigated the effect of hypoxia on the proliferation of microvascular endothelial cells in the brain. Endothelial cells derived from microvessels of Mongolian gerbil brain and control cells (3T3) were incubated for 7 days under various hypoxic and normoxic conditions at 37°C. The proliferation of endothelial cells was inhibited by severe hypoxia, but stimulated by moderate hypoxia. No significant effect of hypoxia on the proliferation of control cells was observed. Endothelial cell-conditioned medium cultured under moderate hypoxia did not affect the growth of endothelial cells. The stimulatory effect of moderate hypoxia on the proliferation of cultured endothelial cells is due to an inherent property of brain endothelial cells.
Phosphorylethanolamine (PEA) is the major component of the phosphomonoester peak detected by phosphorus-31 magnetic resonance spectroscopy, but the absolute concentration has not been determined. This study measured the PEA concentration in biopsy specimens of brain tumors and lobectomized cerebral cortex using high-performance liquid chromatography. The concentration of PEA was 118.5 ± 10.0 μmol/100 g wet wt in cortex, and was significantly higher in malignant gliomas, metastatic pulmonary adenocarcinoma, and neurinoma. The concentration of PEA was especially high in pituitary adenoma, malignant lymphoma, and medulloblastoma.
A 20-year-old female presented with dysphasia and slight hemiparesis following a head trauma, who had a non-treated growing skull fracture which had remained asymptomatic for about 18 years, despite an encephalocele in the left parietal region. Neuroimaging demonstrated secondary brain damage and herniated brain resulting in gliosis. Electroencephalography revealed epileptic discharge in the affected region. Dural repair and cranioplasty resolved her neurological deficits. Early corrective surgery should be performed for growing skull fracture to prevent secondary brain damage.
A 27-year-old male presented with intracranial embolization due to accidental penetration of his neck by an iron fragment at work. Cerebral angiography revealed foreign body embolization of the left middle cerebral artery. The foreign body was successfully removed via craniotomy and arteriotomy. The extended period from onset to surgical treatment prevented acute hemodynamic reconstruction. However, he had good collateral circulation and was discharged with mild hemiparesis and moderate motor aphasia. The possibility of intracranial embolization should be considered in patients presenting with penetrating injury of the neck.
A 16-year-old girl presented with a pleomorphic adenoma of the lacrimal gland manifesting as left painless exophthalmos which had persisted for 3 years. Computed tomography revealed a tumor about 15 mm in diameter in the superolateral site of the left orbit. The tumor was removed completely by combined orbitofrontal craniotomy through a transcranial approach. Histological examination demonstrated the growth of tumor cells as glandular cavities or sheets, with myxoid and partly chondroid connective tissue stroma. Pleomorphic adenoma of the lacrimal gland is unusual in adolescents.
A 46-year-old male with xeroderma pigmentosum developed an intracranial malignant schwannoma originating from the second branch of the left trigeminal nerve. The tumor was subtotally removed and postoperative radiation therapy given, but the tumor recurred twice over 3 years, and extended to the third branch of the left trigeminal nerve and the ipsilateral facial nerve. Radical surgery and radiation therapy finally achieved a cure. This is the first case of malignant trigeminal schwannoma with xeroderma pigmentosum, although various other internal neoplasms including central nervous system tumors have been reported in xeroderma pigmentosum patients. Radical surgery and radiation therapy are effective for treating intracranial malignant schwannoma. Radiation therapy is considered safe for xeroderma pigmentosum patients.
A 48-year-old female presented with four aneurysms in the anterior half of the circle of Willis associated with aortitis syndrome. All the aneurysms were successfully clipped. In general, intracranial hemodynamic change, due to stenosis or occlusion of carotid arteries, is considered to initiate aneurysm growth in the vertebrobasilar system in this syndrome, but renal hypertension was probably involved in our patient. Careful screening for multiple aneurysms, even in the anterior circulation, should be undertaken in patients with aortitis syndrome who present with an aneurysm.
A female infant manifested a rare case of spontaneous regression of a vascular malformation in the occipital lobe after removal of another arteriovenous malformation in the frontal lobe. She was born with multiple nevi on the face, body, and upper and lower extremities. She demonstrated developmental retardation at 8 months of age. Computed tomography at 11 months of age demonstrated ventricular enlargement and a mass in the subdural portion of the left anterior fossa. Magnetic resonance images demonstrated signal void signs in the left frontal lobe, which suggested vascular malformation. Cerebral angiograms disclosed two vascular malformations. The malformation in the frontal lobe was totally removed. Cerebral angiograms 25 days after the operation failed to demonstrate either vascular malformation previously observed. Hemodynamic change following the removal of the arteriovenous malformation may have contributed to the occlusion of the remaining malformation.
A 50-year-old female presented with an unusual giant intracranial aneurysm that showed rapid, spontaneous thrombus formation and subsequent intramural hemorrhage. The thrombus appeared as a homogeneous area on magnetic resonance images, in contrast to the usual heterogeneous appearance. Two months after thrombus formation, the aneurysm had grown and developed intramural hemorrhage. The growth of giant intracranial aneurysms is related to neovascularization and recurrent intramural hemorrhage. The rapid formation of an intra-aneurysmal thrombus may stimulate neovascularization, resulting in intramural hemorrhage and aneurysmal growth.
The brain areas perfused by superselective intra-arterial (i.a.) chemotherapy were assessed using single photon emission computed tomography (SPECT) with technetium-99m-hexamethyl-propyleneamine oxime (99mTc-HMPAO). A superselective catheter was introduced into the anterior, middle, or posterior cerebral artery of patients with malignant glioma for i.a. chemotherapy. 99mTc-HMPAO was subsequently injected via the same catheter used for chemotherapy, and a higher dose of 99mTcHMPAO was injected intravenously to obtain adequate background brain images. Comparison of the SPECT images with magnetic resonance images could confirm complete perfusion of the tumor tissue. In two patients with malignant glioma, regions of interest were selected in the peritumoral brain area and a reference brain area, and the radioactivity was measured. The concentration of 99mTc-HMPAO was about 50 times higher in tissue perfused by superselective injection into anterior or middle cerebral artery compared to intravenous injection. 99mTc-HMPAO SPECT is readily available in many institutions and the information provided is useful for planning more effective and safe i.a. chemotherapy.