Ependymomas: Prognostic Factors and Outcome Analysis in a Retrospective Series of 33 Patients.

BACKGROUND: The purpose of this study was to evaluate the prognostic factors and outcomes in patients with ependymoma to management plans. METHODS: Between 1997 and 2013, 33 patients with 25 ependymomas (WHO grade II) and eight anaplastic ependymomas (WHO grade III) were pathologically diagnosed. Six were pediatric patients (mean age, 6.15 years; range, 1.3-11 years), while 27 were adults (mean age, 47.5 years; range, 19-70 years). Of those, there were 12 adult patients with totally resected ependymomas without anaplastic pathology and adjuvant treatment. Prognostic factors were assessed in ependymoma patients. Prognostic factors were studied using Kaplan-Meier estimates in subgroups. RESULTS: For six pediatric patients, the progression-free survival (PFS) was 43.7±13.5 months, and the overall survival (OS) was 58.1±13.7 months. For 27 adult patients, the PFS was 125.6±14.3 months, and the OS was 151.2±12.5 months. Age demonstrated a statistically significant effect on PFS (p=0.03) and OS (p=0.03). In adult ependymomas, the extent of tumor removal significantly affected PFS (p=0.03) and trended towards an effect on OS (p=0.06). Out of 12 patients with totally resected ependymomas without anaplastic pathology and adjuvant treatment, one patient showed tumor recurrence during follow-up (mean, 93.5 months; range, 27.9-162.7 months). CONCLUSION: Adult patients with ependymomas were found to have better survival rates compared to pediatric patients. We suggest that totally resected adult ependymomas without anaplastic pathology could be observed without any adjuvant treatment, regardless of the tumor location.

Prevention of Complications in Endoscopic Third Ventriculostomy.

A variety of complications in endoscopic third ventriculostomy have been reported, including neurovascular injury, hemodynamic alterations, endocrinologic abnormalities, electrolyte imbalances, cerebrospinal fluid leakage, fever and infection. Even though most complications are transient, the overall rate of permanent morbidity is 2.38% and the overall mortality rate is 0.28%. To avoid these serious complications, we should keep in mind potential complications and how to prevent them. Proper decisions with regard to surgical indication, choice of endoscopic entry and trajectory, careful endoscopic procedures with anatomic orientation, bleeding control and tight closure are emphasized for the prevention of complications.

Traumatic Dural Venous Sinus Injury.

OBJECTIVE: The importance of traumatic dural venous sinus injury lies in the probability of massive blood loss at the time of trauma or emergency operation resulting in a high mortality rate during the perioperative period. We considered the appropriate methods of treatment that are most essential in the overall management of traumatic dural venous sinus injuries. METHODS: We conducted a retrospective review of all cases involving patients with dural venous sinus injury who presented to our hospital between January 1999 and December 2014. RESULTS: Between January 1999 and December 2014, 20 patients with a dural venous sinus injury out of the 1,200 patients with severe head injuries who had been operated upon in our clinic were reviewed retrospectively. There were 17 male and 3 female patients. In 11 out of the 13 patients with a linear skull fracture crossing the dural venous sinus, massive blood loss from the injured sinus wall could be controlled by simple digital pressure using Gelfoam. All 5 patients with a linear skull fracture parallel to the sinus over the venous sinus developed massive sinus bleeding that could not be controlled by simple digital pressure. CONCLUSION: When there is a linear skull fracture parallel to the sinus over the dural venous sinus or a depressed skull fracture penetrating the sinus, the surgeon should be prepared for the possibility of potentially fatal venous sinus injury, even in the absence of a hematoma.

Predictive factors for a kyphosis recurrence following short-segment pedicle screw fixation including fractured vertebral body in unstable thoracolumbar burst fractures.

OBJECTIVE: The technique of short segment pedicle screw fixation (SSPSF) has been widely used for stabilization in thoracolumbar burst fractures (TLBFs), but some studies reported high rate of kyphosis recurrence or hardware failure. This study was to evaluate the results of SSPSF including fractured level and to find the risk factors concerned with the kyphosis recurrence in TLBFs. METHODS: This study included 42 patients, including 25 males and 17 females, who underwent SSPSF for stabilization of TLBFs between January 2003 and December 2010. For radiologic assessments, Cobb angle (CA), vertebral wedge angle (VWA), vertebral body compression ratio (VBCR), and difference between VWA and Cobb angle (DbVC) were measured. The relationships between kyphosis recurrence and radiologic parameters or demographic features were investigated. Frankel classification and low back outcome score (LBOS) were used for assessment of clinical outcomes. RESULTS: The mean follow-up period was 38.6 months. CA, VWA, and VBCR were improved after SSPSF, and these parameters were well maintained at the final follow-up with minimal degree of correction loss. Kyphosis recurrence showed a significant increase in patients with Denis burst type A, load-sharing classification (LSC) score >6 or DbVC >6 (p<0.05). There were no patients who worsened to clinical outcome, and there was no significant correlation between kyphosis recurrence and clinical outcome in this series. CONCLUSION: SSPSF including the fractured vertebra is an effective surgical method for restoration and maintenance of vertebral column stability in TLBFs. However, kyphosis recurrence was significantly associated with Denis burst type A fracture, LSC score >6, or DbVC >6.

Arachnoid Membrane Suturing for Prevention of Subdural Fluid Collection in Extracranial-intracranial Bypass Surgery.

OBJECTIVE: Water-tight closure of the dura in extracranial-intracranial (EC-IC) bypass is impossible because the superficial temporal artery (STA) must run through the dural defect. Consequently, subdural hygroma and subcutaneous cerebrospinal fluid (CSF) collection frequently occur postoperatively. To reduce these complications, we prospectively performed suturing of the arachnoid membrane after STA-middle cerebral artery (STA-MCA) and evaluated the clinical usefulness. MATERIALS AND METHODS: Between Mar. 2005 and Oct. 2010, extracranial-intracranial arterial bypass (EIAB) with/without encephalo-myo-synangiosis was performed in 88 cases (male : female = 53 : 35). As a control group, 51 patients (57 sides) underwent conventional bypass surgery without closure of the arachnoid membrane. Postoperative computed tomography (CT) scan was performed twice in three days and seven days later, respectively, for evaluation of the presence of subdural fluid collection and other mass lesions. RESULTS: The surgical result was excellent, with no newly developing ischemic event until recent follow-up. The additional time needed for arachnoid suture was five to ten minutes, when three to eight sutures were required. Post-operative subdural fluid collection was not seen on follow-up computed tomography scans in all patients. CONCLUSION: Arachnoid suturing is simple, safe, and effective for prevention of subdural fluid collection in EC-IC bypass surgery, especially the vulnerable ischemic hemisphere.

Traction Induced Vertical Displacement of Odontoid due to Type III Odontoid Fracture with Unrecognized Ligamentous Injury: A Case Report.

Dens fractures are a common traumatic cervical spine injury. Among them, a type III fracture is the second common fracture. Although there are several treatment options, it has been accepted that type III fracture is usually healed by non-surgical method. After adequate reduction with traction, subsequent external immobilization has been associated with successful union rates. However, in the review of literatures, there are some cases with neurological deterioration after application of skull traction. So, the authors report a case of type III dens fracture with initially unrecognized ligamentous injury in which vertical dissociation and quadriplegia occurred after only five-pound Gardner-Well tongs traction. And also, the authors raise awareness of this potentially injury.

Value of indocyanine green videoangiography in deciding the completeness of cerebrovascular surgery.

OBJECTIVE: Recently, microscope-integrated near infrared indocyanine green videoangiography (ICG-VA) has been widely used in cerebrovascular surgery because it provides real-time high resolution images. In our study, we evaluate the efficacy of intraoperative ICG-VA during cerebrovascular surgery. METHODS: Between August 2011 and April 2012, 188 patients with cerebrovascular disease were surgically treated in our institution. We used ICG-VA in that operations with half of recommended dose (0.2 to 0.3 mg/kg). Postoperative digital subtraction angiography and computed tomography angiography was used to confirm anatomical results. RESULTS: Intraoperative ICG-VA demonstrated fully occluded aneurysm sack, no neck remnant, and without vessel compromise in 119 cases (93.7%) of 127 aneurysms. Eight clipping (6.3%) of 127 operations were identified as an incomplete aneurysm occlusion or compromising vessel after ICG-VA. In 41 (97.6%) of 42 patients after carotid endarterectomy, the results were the same as that of postoperative angiography with good patency. One case (5.9%) of 17 bypass surgeries was identified as a nonfunctioning anastomosis after ICG-VA, which could be revised successfully. In the two patients of arteriovenous malformation, ICG-VA was useful for find the superficial nature of the feeding arteries and draining veins. CONCLUSION: ICG-VA is simple and provides real-time information of the patency of vessels including very small perforators within the field of the microscope and has a lower rate of adverse reactions. However, ICG-VA is not a perfect method, and so a combination of monitoring tools assures the quality of cerebrovascular surgery.

The usefulness of electromagnetic neuronavigation in the pediatric neuroendoscopic surgery.

OBJECTIVE: Neuroendoscopy is applied to various intracranial pathologic conditions. But this technique needs informations for the anatomy, critically. Neuronavigation makes the operation more safe, exact and lesser invasive procedures. But classical neuronavigation systems with rigid pinning fixations were difficult to apply to pediatric populations because of their thin and immature skull. Electromagnetic neuronavigation has used in the very young patients because it does not need rigid pinning fixations. The usefulness of electromagnetic neuronavigation is described through our experiences of neuroendoscopy for pediatric groups and reviews for several literatures. METHODS: Between January 2007 and July 2011, nine pediatric patients were managed with endoscopic surgery using electromagnetic neuronavigation (AxiEM, Medtronics, USA). The patients were 4.0 years of mean age (4 months-12 years) and consisted of 8 boys and 1 girl. Totally, 11 endoscopic procedures were performed. The cases involving surgical outcomes were reviewed. RESULTS: The goal of surgery was achieved successfully at the time of surgery, as confirmed by postoperative imaging. In 2 patients, each patient underwent re-operations due to the aggravation of the previous lesion. And one had transient mild third nerve palsy due to intraoperative manipulation and the others had no surgery related complication. CONCLUSION: By using electromagnetic neuronavigation, neuroendoscopy was found to be a safe and effective technique. In conclusion, electromagnetic neuronavigation is a useful adjunct to neuroendoscopy in very young pediatric patients and an alternative to classical optical neuronavigation.

Prognostic significance of neuronal marker expression in glioblastomas.

PURPOSE: Glioblastomas are the most malignant tumors of central nervous system neoplasms and are well known for their biological heterogeneity. Contrary to the putative hypothesis of purely glial differentiation in glioblastomas, they often demonstrate immunopositivity for neuronal markers. However, the significance of their neuronal marker expression is still controversial. To evaluate the prognostic implication of neuronal expression in glioblastoma, this study investigated the expression of neuronal markers in a large series of glioblastoma patients in terms of patient survival rate. METHODS: Expression of synaptophysin, neurofilament protein, and NeuN was explored using immunohistochemistry in 88 cases of glioblastoma. Clinicopathological variables as well as patients' survival data were compared according to the immunopositivity of cases. RESULTS: Sixty-one of the 88 tumors (69.3 %) were positive for at least one neuronal marker. Synaptophysin positivity was observed in 43 cases (48.9 %). Neurofilament protein and NeuN were positive in 38 (43.2 %) and 42 cases (47.7 %), respectively. There was no statistically significant difference in overall survival and progression-free survival in association with neuronal marker expression. However, gross total removal or combined radiotherapy and chemotherapy significantly prolonged survival (P=0.041 and 0.044). Cox's proportional hazard model revealed that NeuN expression was the independent prognostic factors in progression-free survival (P=0.012). CONCLUSIONS: Although the correlation of neuronal marker expression and clinical outcome in glioblastoma is of considerable interest, the presented data support the limited prognostic value of neuronal marker expression in glioblastoma.

Post-traumatic cerebral infarction : outcome after decompressive hemicraniectomy for the treatment of traumatic brain injury.

OBJECTIVE: Posttraumatic cerebral infarction (PTCI), an infarction in well-defined arterial distributions after head trauma, is a known complication in patients with severe head trauma. The primary aims of this study were to evaluate the clinical and radiographic characteristics of PTCI, and to assess the effect on outcome of decompressive hemicraniectomy (DHC) in patients with PTCI. METHODS: We present a retrospective analysis of 20 patients with PTCI who were treated between January 2003 and August 2005. Twelve patients among them showed malignant PTCI, which is defined as PTCI including the territory of Middle Cerebral Artery (MCA). Medical records and radiologic imaging studies of patients were reviewed. RESULTS: Infarction of posterior cerebral artery distribution was the most common site of PTCI. Fourteen patients underwent DHC an average of 16 hours after trauma. The overall mortality rate was 75%. Glasgow outcome scale (GOS) of survivors showed that one patient was remained in a persistent vegetative state, two patients were severely disabled and only two patients were moderately disabled at the time of discharge. Despite aggressive treatments, all patients with malignant PTCI had died. Malignant PTCI was the indicator of poor clinical outcome. Furthermore, Glasgow coma scale (GCS) at the admission was the most valuable prognostic factor. Significant correlation was observed between a GCS less than 5 on admission and high mortality (p<0.05). CONCLUSION: In patients who developed non-malignant PTCI and GCS higher than 5 after head injury, early DHC and duroplasty should be considered, before occurrence of irreversible ischemic brain damage. High mortality rate was observed in patients with malignant PTCI or PTCI with a GCS of 3-5 at the admission. A large prospective randomized controlled study will be required to justify for aggressive treatments including DHC and medical treatment in these patients.

Rapid progression of unilateral moyamoya disease.

The detailed clinical characteristics of unilateral moyamoya disease (MMD) have not been fully elucidated. It has been reported that some patients with unilateral MMD progress to bilateral involvement, while others remain with the unilateral variant. In this series, we present a case of unilateral MMD that progressed to bilateral involvement over the course of just one month.

Increased expression of L-amino acid transporters in balloon cells of tuberous sclerosis.

OBJECTS: Tuberous sclerosis complex (TSC) is a dysgenetic syndrome involved in multiple organs, and the pathognomonic cortical tuber act as an epileptic substrate. The amino acid transport system L (LAT) is a major nutrient transport system, and LAT1 is highly expressed in malignant tumors to support tumor cell growth. To study the life-long epilepsy from the cortical tuber, the expression of LAT1 in balloon cells and dysplastic neurons of the cortical tuber is investigated. MATERIALS AND METHODS: LAT1 expression was investigated by LAT1 mRNA using reverse transcription-polymerase chain reaction and immunohistochemical staining with anti-human LAT1 antibody in nine patients with TSC and three control brains. CONCLUSION: LAT1 mRNA was detectable only in fresh-frozen tissues of TSC, and it was upregulated in the cortical tuber lesion. While the LAT1 immunopositivity of control brains was limited in the capillary endothelial cells in the gray matter, increased LAT1 immunopositivity was noted in balloon cells of the cortical tubers in addition to the capillary endothelial cells as shown in control brains. Linear and strong immunopositivity along the cell membrane and cytoplasm of the balloon cells, and weakly granular immunopositivity in their cytoplasm were noted. Increased expression of LAT1 in the balloon cells is important for the active transport of large neutral amino acids into the balloon cells, and that the biologic process may play an important role in the active protein synthesis with metabolic maintenance of balloon cells in cortical tubers of patients with TSC.

Endocrinological outcomes of pediatric craniopharyngiomas with anatomical pituitary stalk preservation: preliminary study.

OBJECTIVE: We reviewed 17 pediatric craniopharyngioma patients, with a special focus on endocrinological outcomes and tumor recurrence with pituitary stalk preservation. METHODS: From 1992 to February 2008, 17 patients underwent 27 surgical procedures. The male-female patient ratio was 12:5 and median patient age was 12 years (range, 4-18 years). The median follow-up period was 4.97 years (range, 1.16-15.08 years). The most frequent major presenting symptom was increased intracranial pressure (in 76.5%), followed by visual disturbance (in 23.5%). Tumors were totally removed in 70.6% of patients, subtotally removed in 23.5% and partially removed in 5.9%. RESULTS: The postoperative visual improvement rate was 47.6% and the postoperative visual deterioration rate was 33.3%. In 7 patients with stalk preservation, 1 received partial hormone replacement and 6 received total hormone replacement. The overall tumor recurrence and re-growth rate were 52.9%. In patients who did not receive radiotherapy immediately after their first operation, the recurrence-free survival rate differed between those with pituitary stalk preservation and those with stalk section (p = 0.04). The recurrence rate was 60% (3 of 5) in the former and 33.3% (3 of 9) in the latter. Two patients who had undergone a second operation for recurrences died. The operative morbidity rate was 23.5%. CONCLUSIONS: Pediatric craniopharyngiomas had high recurrence rates and low pituitary functional preservation despite anatomical stalk preservation. Therefore, maximal tumor resection might be more important than anatomical stalk preservation in pediatric craniopharyngiomas.

Spontaneous resolution of a traumatic cervicothoracic epidural hematoma presenting with transient paraplegia: a case report.

STUDY DESIGN: Case description. OBJECTIVE: To clinically and radiographically describe a traumatic spinal epidural hematoma (TSEH) without adjacent spinal column fracture or soft tissue injury that completely resolved, without surgical intervention. SUMMARY OF BACKGROUND DATA: Symptomatic TSEH is an infrequent condition after spinal trauma, accounting for 0.5% to 1.7% of cases. It can result in permanent neurologic deficits if not treated in a timely and appropriate manner. METHODS: A 50-year-old man presented with progressive lower motor weakness and sensory change at 2 days after blunt trauma to the upper back area. Neurologic examination revealed paraplegia and hypesthesia below the T4 sensory dermatome. Magnetic resonance imaging for cervicothoracic spine showed a space-occupying lesion in the dorsal spinal epidural space from C7 to T5. The lesion was consistent with acute stage hematoma of the spinal epidural space. RESULTS: The patient was prepared for decompression surgery. However, the patient's neurologic symptoms began to improve (grade 4/5) at 2 hours after onset of paraplegia. Surgical intervention was delayed, and the patient was treated conservatively with close neurologic monitoring. Three days after onset of symptoms, the patient's neurologic symptoms recovered completely. The follow-up magnetic resonance imaging at 12 days after the event showed complete resolution of the epidural hematoma. CONCLUSION: An unpredictable extensive epidural hematoma can occur after blunt trauma of the cervicothoracic spine in patients at low risk for hemorrhage. This case illustrates that immediate surgical intervention may not always be necessary in certain patients with TSEH. Conservative management with careful observation may play a role as a management option for patients initially presenting with severe neurologic dysfunction if neurologic recovery is early and sustained.

The clinical utility of the Kopitnik arteriovenous malformation microclip during STA-MCA bypass surgery.

PURPOSE: Yasagil temporary clips have been widely used in extracranial-intracranial (EC-IC) arterial bypass surgery. However, the extremely delicate vessels involved often require the application of finer clips. We report on the use of the Kopitnik arteriovenous malformation (AVM) microclip system for superficial temporal artery-middle cerebral artery (STA-MCA) bypass. METHODS: Kopitnik AVM microclips are new mechanical devices that are used during AVM surgery. They exert a pre-defined closing force of 50-70 g, and also feature a special, pyramid-shaped structure stamped on inner surfaces of the blades. These characteristics avoid vascular intimal injury and provide a secure grip. We prospectively studied their use in 15 patients requiring STA-MCA anastomosis. RESULTS: Clinical results were excellent and there were no new ischemic events during 6-months' follow-up. CONCLUSIONS: Kopitnik AVM microclips have several advantages; they have small and variously sized clip blades (2, 3, 4 and 5 mm), and the small clip head allows the operator an excellent view of the pathology and clip status. The Kopitnik AVM microclip appears to be clinically effective and safe for EC-IC bypass surgery, especially when smaller vessels are involved.

Thoracic myelopathy caused by ossification of the ligamentum flavum.

OBJECTIVE: Ossification of the ligamentum flavum (OLF) is a rare cause of thoracic myelopathy. The aim of this study was to identify factors associated with the surgical outcome on the basis of preoperative clinical and radiological findings. METHODS: Data obtained in 26 patients whot underwent posterior decompression for thoracic myelopathy, caused by thoracic OLF, were analyzed retrospectively. Patient age, duration of symptoms, OLF type, preoperative and postoperative neurological status using the Japanese Orthopedic Association (JOA) scoring system, surgical outcome, and other factors were reviewed. We compared the various factors and postoperative prognosis. All patients had undergone decompressive laminectomy and excision of the OLF. RESULTS: Using the JOA score, the functional improvement was excellent in 8 patients, good in 14, fair in 2, and unchanged in 2. A mean preoperative JOA score of 6.65 improved to 8.17 after an average of 27.3 months. According to our analysis, age, gender, duration of symptoms, the involved spinal level, coexisting spinal disorders, associated trauma, intramedullary signal change, and dural adhesions were not related to the surgical outcome. However, the preoperative JOA score and type of OLF were the most important predictors of the surgical outcome. CONCLUSION: Early diagnosis and sufficient surgical decompression could improve the functional prognosis for thoracic OLF. The postoperative results were found to be significantly associated with the preoperative severity of myelopathy and type of OLF.

Surgical strategies using cerebral revascularization in complex middle cerebral artery aneurysms.

OBJECTIVES: To describe surgical strategies using cerebral revascularization for complex middle cerebral artery aneurysms unsuitable to microsurgical clipping. MATERIALS AND METHODS: In this study, the clinical features, case management, and results in 9 consecutive patients who underwent 10 cerebral revascularization procedures between January 1999 and April 2008 were retrospectively analyzed. The patient population consisted of 6 men and 3 women whose ages ranged from 15 to 71 years (mean, 42.4 years). The size of the aneurysms ranged from 12 to 35 mm (mean, 24.3 mm). Treated aneurysms were located in the M1 segment in 2 patients, the middle cerebral artery (MCA) bifurcation in 3 patients, the distal M3 segment in 3 patients, and the anterior temporal artery (ATA; the early cortical branch of the M1 segment) in 1 patient. A total of 10 revascularizations were performed. Three aneurysms were saccular and six aneurysms were fusiform. For the fusiform aneurysms of the M1 segment in 2 patients, superficial temporal artery (STA) trunk-saphenous vein (SV)-MCA bypasses followed by trapping were performed. For the large saccular MCA bifurcation aneurysms in 3 patients, STA-MCA bypasses followed by complete neck clipping, including the revascularized branch with the preservation of the flow of the other branch, were performed in 2 cases, and a STA trunk-SV-MCA bypass secondary to direct neck clipping with the preservation of both M2 branches was performed in 1 case. For the fusiform distal MCA aneurysms, STA-MCA bypasses in 2 patients and in situ MCA-MCA bypasses in 2 patients were performed. In one case involving distal MCA fusiform aneurysm, STA-MCA bypass and MCA-MCA bypass were performed simultaneously. In a case involving fusiform ATA aneurysm, primary reanastomosis after aneurysm excision was performed in 1 patient. RESULTS: The post-operative 3-month Glasgow outcome scales were good recovery in 6 patients, severe disability in 1 patient, a vegetative state in 1 patient, and death in 1 patient. A follow-up angiography was performed in 6 patients and revealed a patent bypass in 5 patients. In one case treated by direct neck clipping secondary to cerebral revascularization, the angiography obtained 2 weeks later showed graft occlusion, but there were no neurologic symptoms. Among the unfavorable outcomes of 3 patients who did not undergo follow-up angiography, surgery-related morbidity secondary to cerebral infarction was due to the size discrepancy between the donor and recipient vessels in 1 patient with severe disability. In the other 2 patients, the preoperative conditions were Hunt and Hess grade V. CONCLUSIONS: Cerebral revascularization is a safe and effective technique of treatment for selective cases of complex large or giant aneurysms and unclippable fusiform aneurysms in the MCA.

The role of collagen type I alpha2 polymorphisms: intracranial aneurysms in Koreans.

BACKGROUND: The COL1A2 is located on chromosome 7q22.1, and mutations in this gene have been associated with the development of IAs. In this study, we investigated whether the rs42524 and rs2621215 polymorphisms of the COL1A2 gene are associated with the development of cerebral aneurysms in the Korean population. METHODS: This was a hospital-based case control study conducted at Chonnam University Hospital, Gwangju, Korea. The study population consisted of 320 patients who had been treated for IA and 189 healthy hospital-based controls (angiographically negative for an IA). Two polymorphic loci were amplified by polymerase chain reaction, namely, rs42524 in exon 28 and rs2621215 in intron 46 of the COL1A2 gene, and analyzed by RFLP using HhaI or BfaI restriction enzymes, respectively. RESULTS: The genotype frequencies of rs42524 in cases were 88.0%, 11.4%, and 0.6% for the GG, GC, and CC genotypes, respectively, and in controls were 88.9%, 10.0%, and 1.1%, respectively. Similarly, the genotype frequencies of rs2621515 in cases were 88.0%, 10.1%, and 0.2% for the TT, TG, and GG genotypes, respectively, and among controls were 92.1%, 7.9%, and 0%, respectively. CONCLUSION: The rs2621215 SNP in intron 46 of the COL1A2 gene was found to be marginally associated with an increased risk of IA development in the Korean population examined. In contrast, rs42524 showed no association with an increased risk of IA development.

Post-traumatic intradiploic leptomeningeal cyst of the posterior fossa in an adult.

Intradiploic cysts in the posterior fossa are rare. We report a post-traumatic intradiploic leptomeningeal cyst in an adult and review the diagnosis and pathogenesis of this lesion. A 28-year-old woman presented with a headache and a hard mass in the occipital region. She had a history of head injury as she had fallen from a height at the age of 18 months. CT scans and MRI revealed an expanding intradiploic cyst with the density of cerebrospinal fluid (CSF) and thinning of the inner and outer tables. A bony defect of the inner table connecting to the cisterna magna was also visualized. At surgery, we detected free communication of the CSF between the cystic cavity and the subarachnoid space of the posterior fossa via a defect in the dura and inner table. The dural defect was sutured primarily and covered with the autogenous outer table. An intradiploic cyst of the occipital bone can be detected in adults and might be caused by remote head injuries during childhood. Prompt surgical repair of the dural and bony defect in an adult patient has an excellent prognosis.

Intramedullary subependymoma of the thoracic spinal cord.

We report a rare case of a thoracic intramedullary subependymoma in a 37-year-old woman. The patient developed a monoparesis of the right leg after a subtotal resection of the tumor. During the 30 months of follow-up the neurological deficit improved and the patient remained symptom free without progression of the remnant tumor. A complete resection of the tumor is usually curative with improved function. However, aggressive surgery may cause either worsening of an existing deficit or the development of new deficits. In patients with poor delineation between the tumor and the spinal cord, subtotal removal and close follow-up should be considered.