Meningioma arises from the arachnoid cap cell found in the arachnoid layer of the meninges. Most meningiomas are located in the subdural space. Meningiomas are mostly found in adulthood between 20 and 60 years of age. A case of intracranial epidural meningioma without involvement of the subdural space is reported.
Adolescent* ; Arachnoid ; Epidural Neoplasms ; Humans ; Meninges ; Meningioma* ; Subdural Space

The intracranial arachnoid cysts are benign lesions in nature which thin walled cysts lying in relation to or enclosed by the subarachnoid space, filled with clear fluid. They may be due to developmental defects of the brain or meninges and secondary to inflammation, vascular occlusion or trauma but etiology of a large percentage is not well understood. In general, locations are near primary fissure and cisterns of the cerebral cortex and cerebellum. The clinical features and courses are unusual. Preoperative diagnosis is unlikely to be made but treatment is followed by good result. We had experienced two cases of intracranial arachnoid cysts which occurs in middle cranial fossa, and cerebral hemisphere. Pathologic diagnosis are arachnoid cysts.
Arachnoid Cysts* ; Brain ; Cerebellum ; Cerebral Cortex ; Cerebrum ; Cranial Fossa, Middle ; Deception ; Diagnosis ; Inflammation ; Meninges ; Subarachnoid Space

Meningiomas are common intracranial tumors arising from the arachnoid cells of the meninges, but the neurosurgical frequency of multiple intracranial meningiomas is low ; the pathogenesis of multiple meningioma is still unknown. The authors report sixth cases of multiple intracranial meningiomas, representing 3.3% of all meningiomas surgically removed at our hospital during the past ten years. Four cases were female. In four cases the meningiomas affected one hemisphere, and 62% were located in the convexity. All tumors were removed in one stage and except in case 5, there has been no recurrence. In this report, we present precise descriptions of cases 3 and 5.
Arachnoid ; Female ; Humans ; Meninges ; Meningioma* ; Recurrence

It is important to obtain a good exposure of the root exit zone(REZ) of the facial nerve during microvascular decompression(MVD) for hemifacial spasm(HFS). For this purpose, authors dissected cerebellar cortical artery in addition to exposing the proximal portion of lower cranial nerves. During MVD for HFS, surgeons frequently meet a cerebellar cortical artery along the inferolateral aspect of cerebellar hemisphere. It is usually hemispheric branch of anterior inferior cerebellar artery(AICA) or posterior inferior cerebellar artery(PICA). It is reason that authors have dissected the outside arachnoid membrane attached pia mater of cerebellar cortical artery with a arachnoid knife or microscissor but preserve the inside arachnoid membrane attached dura mater. Microsurgical retractor is placed inferolaterally between cerebellar cortical artery and cerebellar hemisphere and elevated from the floor of the posterior fossa. The subarachnoid cisterns over the lower cranial nerves are opened with sharp dissector and wide operative fields and good exposure of REZ of facial nerve is obtained.
Arachnoid ; Arteries* ; Cranial Nerves ; Dura Mater ; Facial Nerve ; Hemifacial Spasm* ; Membranes ; Microvascular Decompression Surgery* ; Pia Mater

Defects in the dura mater can be result from craniocerebral trauma, neoplastic or inflammatory destruction surgical removal and congenital absence. Materials used for closure of dural defects were variable. Of these, autogenous fascia lata have been used for a long time. It seems interesting to study the histologic fate of the autogenous grafted fascia lata in the dural defects. After autogenous fascia lata graft to dural defect in 18 rabbits, the histologic fate of the autogenous grafted fascia lata was observed microscopically. The results are as follows: 1) The adhesions among the grafted fascia lata, arachnoid, pia mater and brain cortex were usually mild. This result may be due to either short period of observation or autogenous substitutional material. 2) The grafted autogenous fascia lata was revealed minimal inflammatory response and was ultimately reabsorbed. 3) The grafted autogenous fascia lata was replaced by granulation tissue and fibroblast originated from the host mesenchymal tissue.
Arachnoid ; Brain ; Craniocerebral Trauma ; Dura Mater ; Fascia Lata* ; Fascia* ; Fibroblasts ; Granulation Tissue ; Pia Mater ; Rabbits* ; Transplants

The spinal canal takes the form of a series of cylinders designated by their relationship to the meninges and is divided by the dura mater into the epidural or extradural space and the intradural space. The epidural space is composed of spinal ligaments, connective and areolar tissue, the epidural venous plexus, lymphatic channels and supporting elements, and various pathologic entities are found there. MR imaging can accurately depict the extent and characteristics of lesions, and in some cases specific diagnosis is possible. In this pictorial essay, we illustrate a variety of spinal epidural lesions and their MR findings.
Diagnosis ; Dura Mater ; Epidural Space ; Ligaments ; Magnetic Resonance Imaging ; Meninges ; Spinal Canal

Bone Neoplasms ; pathology ; Chondrosarcoma, Mesenchymal ; pathology ; Dura Mater ; pathology ; Humans ; Meninges ; pathology

Variations of the dural folds and the dural venous sinuses are infrequently reported in the existing medical literature. Such variations in the posterior cranial fossa may pose difficulties in various analytical and surgical procedures of this region. We present a rare concurrent variation of the falx cerebelli and tentorium cerebelli that was detected during routine dissection of an adult male cadaver. While removing the brain, a partial duplication of tentorium cerebelli was observed below the left half of the tentorium cerebelli and above the left cerebellar hemisphere. This fold did not have any dural venous sinus in it. Further, a complete duplication of falx cerebelli with a single occipital venous sinus within its attached border was also observed. We present the review of literature and discuss the comparative anatomy of this case.
Adult ; Anatomy, Comparative ; Brain ; Cadaver ; Cranial Fossa, Posterior ; Dura Mater ; Humans ; Male ; Meninges ; Spinal Cord

Drainage ; Dura Mater ; blood supply ; Humans ; Intracranial Arteriovenous Malformations ; diagnostic imaging ; surgery ; Male ; Meninges ; blood supply ; Middle Aged ; Radiography

PURPOSE: The purpose of this study was to evaluate the usefulness of computed tomography(CT) and magnetic resonance imaging(MRI) in experimental bacterial meningitis. MATERIALS AND METHODS: CT and MR images of experimental bacterial meningitis were obtained after inoculation of 1ml suspension of 106/ml Staphylococcusaureus directly into the supratentorial arachnoid space of 18 New Zealand white rabbits. Each animal was studied with both Pre-enhanced and post-enhanced CT and MRI at 12, 24, 48 hours and 1 week. Cerebrospinal fluid of all of18 rabbits were sampled and cultured for bacterial growth. RESULTS: All of 18 rabbits had the clinical symptoms such as neck stiffness and anorexia within 24 hours after the inoculation. Cerebrospinal fluid cultures werepositive for Staphylococcus sureus growth. Gd-enhanced MRI exhibited diffuse enhancement along the thickened supratentorial meninges earlier than CT. in Gd-enhanced MRI, the mean contrast enhancement ratio(CER) at supratentorial meninges increased to 1.93 at 12 hours and 2.99 at 24 hours from 1.06 at 0 hour. Histologic evaluation demonstrated inflammatory cell infiltration into the meninges. MRI also identified the complications of mening it is such as ependymitis and hydrocephalus more effectively than CT. CONCLUSION: These results indicatedthat Gd-enhanced MRI detected earlier the abnormal findings of bacterial meningitis and evaluated more effectively the complications of mening it is compared with CT. MRI was more useful than CT in evaluation of the bacterial meningitis.
Animals ; Anorexia ; Arachnoid ; Cerebrospinal Fluid ; Hydrocephalus ; Magnetic Resonance Imaging* ; Meninges ; Meningitis ; Meningitis, Bacterial* ; Neck ; Rabbits ; Staphylococcus