STUDY DESIGN: Review of literature on anatomical and pathophysiological features of cauda equina. OBJECTIVES: To look into the anatomical and pathophysiological features of cauda equina and support their basic knowledge of treating cauda equina syndrome. SUMMARY OF LITERATURE REVIEW: Cauda equina has different anatomical and pathophysiological features to peripheral nerve. MATERIALS AND METHODS: Review of literature. RESULTS: When compressing to cauda equina, the pathophysiologic mechanism develop as follows; increasing the vascular permiablity of nerve root, intraneural edema, and subsequent blood and nutritional impairment. Nerve root injury develops through this pathophysiologic mechanism. CONCLUSIONS: Cauda equina has an extensive ateriovenous anastomosis and guaze-like pia mater, which supply blood and neutrition to it. These anatomical features prevent it from complete cauda equina syndrome when compressing to it under arterial blood pressure.
Arterial Pressure ; Cauda Equina* ; Edema ; Peripheral Nerves ; Pia Mater ; Polyradiculopathy

Malignant melanoma is a relatively rare tumor. It represents 1.4-15.7% of all malignant tumors. Melanin-containing cells are normally found in the pia mater of adult human subjects. A wide variety of disorders ranging from a simple increase in normal leptomeningeal pigmentstion to highly malignant melanoma may be encountered. However, whether benign or malignant, primary melanoma of the nervous system are extremely rare. The diagnosis was confirmed by operation and biopsy. This case, which we have experienced recently, is reported with a review of the literatures.
Adult* ; Biopsy ; Diagnosis ; Humans ; Melanoma ; Nervous System ; Nevus* ; 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

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

Perivascular space (PVS) is a crevice between two slices of cerebral pia maters, filled with tissue fluid, which be formed by pia mater emboling in the surrounding of cerebral perforating branch (excluding micrangium). Normal PVS (diameter < 2 mm) can be found in almost all healthy adults; however enlarged PVS (diameter > 2 mm) has correlation with neurological disorders probably. The article reviews the formation mechanism, imageology characteristics and the relation with neurological disorders of PVS, which is beneficial to the research of some neurological disorders etiopathogenesis and treatment.
Animals ; Blood Vessels ; pathology ; Humans ; Nervous System Diseases ; pathology ; Pia Mater ; pathology

Type IV spinal cord arteriovenous malformation is a spinal vascular anomaly supplied by the anterior spinal artery and drained directly into an enlarged venous outflow. Direct fistula lies completely outside the spinal cord and pia mater. We report a case of intradural perimedullary arteriovenous fistula in 58-years-old man who presented with progressive paraparesis. Angiographically single fistulous perimedullary communication with moderate-sized abnormal venous engorgement was demonstrated through anterior spinal artery. Direct surgical obliteration of the fistulous site was performed. Spinal angiographic evaluation and recognition of their exact pathophysiology according to individual types of spinal AVMs is the most important in successful execution of planned surgery and to achieve the good outcome.
Arteries ; Arteriovenous Fistula* ; Arteriovenous Malformations ; Fistula ; Hyperemia ; Paraparesis ; Pia Mater ; Spinal Cord*

Type IV spinal cord arteriovenous malformation is a spinal vascular anomaly supplied by the anterior spinal artery and drained directly into an enlarged venous outflow. Direct fistula lies completely outside the spinal cord and pia mater. We report a case of intradural perimedullary arteriovenous fistula in 58-years-old man who presented with progressive paraparesis. Angiographically single fistulous perimedullary communication with moderate-sized abnormal venous engorgement was demonstrated through anterior spinal artery. Direct surgical obliteration of the fistulous site was performed. Spinal angiographic evaluation and recognition of their exact pathophysiology according to individual types of spinal AVMs is the most important in successful execution of planned surgery and to achieve the good outcome.
Arteries ; Arteriovenous Fistula* ; Arteriovenous Malformations ; Fistula ; Hyperemia ; Paraparesis ; Pia Mater ; Spinal Cord*

PURPOSE: Complete resection of the tumor nodule(mural nodule or solid portion of the tumor) is the essential goal of surgical treatment for heman-gioblastoma. The purpose of this study was to classify the morphologic types of intracranial hemangioblastoma on MRI and to compare the location and contour of tumor nodule on MRI with those on angiography. MATERIALS AND METHODS: The MRI findings of 34 lesions(38 lesions if 4 spinal cord lesions were included) in 26 patients(17 males and 9 females, range of age, 18-67 years, mean, 39 years) with surgically and histopathologically proved intracranial hemangioblastomas were reviewed. Seventeen patients underwent CT scanning in a short interval. Contrast-enahnced T1 -weighted imaging pa- tterns of hemangioblastoma were classified according to Ho's morphologic types. The location and contour of tumor nodule were compared between MRI and angiography in 15 patients(24 lesions). RESULTS: By location, cerebellar hemisphere was predominated(55%), followed by cerebellar vermis(26%), supratentorial region(5%), and medulla oblongata (3%). Spinal cord lesions(11%) were seen in 3 patients of 5 von HippeI-Lindau diseases. The frequency of morphologic types was as follows; Type 1 (purely cystic), 3%, Type 2(mural nodule), 50%, Type 3(cyst with wall enhancement), 3%, Type 4 (cystic nodule), 15%, Type 5(solid with internal cyst), 9%, and Type 6(solid), 20%. All tumor nodules(33 lesions) enhanced intensely with intravenous contrast material on MRI, of which 24 lesions(in 15 patients) revealed hypervascular masses fed by pial arteries on angiography. They were superficial and abutted pia mater partially or in large portion on both MR I and angiography. CONCLUSION: Over 70% of intracranial hemangioblastomas had a surrounding cyst, and superficial, pial-based location and number of the tumor nodules on MRI was correlated well with those on angiography. MRI is the examination of choice for preoperative evaluation of intracranial hemangioblastoma.
Angiography ; Arteries ; Female ; Hemangioblastoma* ; Humans ; Magnetic Resonance Imaging* ; Male ; Medulla Oblongata ; Pia Mater ; Spinal Cord ; Tomography, X-Ray Computed

OBJECTIVEMultiple subpial transection (MST) is one approach to the surgical treatment of intractable epilepsy with epileptogenic lesion located in functional areas. To verify the effect of MST, an experimental study was performed first, followed by clinical application.

METHODSOn the basis of the experimental study, MST was performed in 200 intractable epileptic patients from 1991 to 2000. Of them, 80 cases underwent MST only while 120 others underwent MST combined with other techniques, such as corpus callosotomy, temporal lobectomy and focus resection. A series of modifications of the surgical techniques were made.

RESULTSThe results of the experimental study indicated that MST could inhibit the formation and spreading of epileptic discharge and limit the damage to neurons in a minimal area on the epileptogenic agent injected cortex. MST does not impair major functions of the cortex. After the clinical application and modifications, 160 patients were followed up for 1 to 8 years. Complete control of seizure was obtained in 100 cases (62.5%), significant reduction (more than 75%) in 32, reduction (more than 50%) in 20 and no change in 8. The total rate of effectiveness was 95.0%, and the significant rate of effectiveness was 82.5%. No functional defects were found in any patients.

CONCLUSIONSThe results indicate that MST is an effective approach to the surgical treatment of intractable epilepsy. MST can be combined with other approaches. The outcome of the subdivision of the MST only group indicates that MST on local epileptogenic lesion without structural changes is as effective as that of the combined operation group. To evade hemispheric disturbance, MST should be done first to avoid severe complications. Hemispherectomy should be performed only on poor effected cases of MST.

Adolescent ; Adult ; Child ; Child, Preschool ; Epilepsy ; surgery ; Female ; Humans ; Male ; Middle Aged ; Pia Mater ; Surgical Procedures, Operative ; methods

Althouth the connective-tissue membrane surrounding a subdural hematoma has been described as hyalinized, calcified partially or in patches, a totally organized, calcified or ossified chronic subdural hematoma in the elderly patient is extremely rate. We report an asymptomatic case of a huge calcified chronic subdural hematoma in a 67-year-old male patient who had no previous trauma history. Computerized tomographic(CT) scan showed an oval-shaped mass with totally calcified rim at the left frontotemporoparietal region. After en-block removal of the calcified mass, postoperative CT scan showed intracerebral hematoma at the deepest portion of the calcified mass that was partially adhesive to the pia mater. The patient suffered from a transient motor aphasia after the operation. Relevant literatures are briefly reviewed.
Adhesives ; Aged ; Aphasia, Broca ; Hematoma ; Hematoma, Subdural ; Hematoma, Subdural, Chronic* ; Humans ; Hyalin ; Male ; Membranes ; Pia Mater ; Tomography, X-Ray Computed