Extent of Contrast Enhancement on Non-Enhanced Computed Tomography after Intra-Arterial Thrombectomy for Acute Infarction on Anterior Circulation: As a Predictive Value for Malignant Brain Edema

OBJECTIVE: To determine whether the use of contrast enhancement (especially its extent) predicts malignant brain edema after intra-arterial thrombectomy (IAT) in patients with acute ischemic stroke. METHODS: We reviewed the records of patients with acute ischemic stroke who underwent IAT for occlusion of the internal carotid artery or the middle cerebral artery between January 2012 and March 2015. To estimate the extent of contrast enhancement (CE), we used the contrast enhancement area ratio (CEAR)-i.e., the ratio of the CE to the area of the hemisphere, as noted on immediate non-enhanced brain computed tomography (NECT) post-IAT. Patients were categorized into two groups based on the CEAR values being either greater than or less than 0.2. RESULTS: A total of 39 patients were included. Contrast enhancement was found in 26 patients (66.7%). In this subgroup, the CEAR was greater than 0.2 in 7 patients (18%) and less than 0.2 in the other 19 patients (48.7%). On univariate analysis, both CEAR > or =0.2 and the presence of subarachnoid hemorrhage were significantly associated with progression to malignant brain edema (p or =0.2 showed a statistically significant association (p=0.019). In the group with CEAR > or =0.2, the time to malignant brain edema was shorter (p=0.039) than in the group with CEAR or =0.2 (p=0.003) CONCLUSION: The extent of contrast enhancement as noted on NECT scans obtained immediately after IAT could be predictive of malignant brain edema and a poor clinical outcome.

Post-Traumatic Arteriovenous Fistula of the Scalp

Arteriovenous fistula of the scalp is relatively rare disease. We report a traumatic arteriovenous fistula of the scalp treated with complete surgical excision and review the literature with regard to etiology, pathogenesis, and management of these unusual lesions.

Three Cases of Calcifying Pseudoneoplasm which Involve the Epidural Space of the Spine

Calcifying psuedoneoplasm of the spine is a rare non-neoplastic lesion of unknown origin. Radiologic and histologic manifestations are very variable and clinical symptoms include isolated pain, myelopathy, and radiculopathy. Surgical resection is the preferred option of treatment. This report describes three cases of calcifying pseudoneoplasm in the spine. The first case is a 77-year-old female with pain in both legs. The second case is a 67-year-old woman who presented as right leg pain. The third case is a 78-year-old woman with isolated back pain. The involved sites of each of cases were T12, L2-3, and L1, respectively. Surgical resection of the involved masses relieved symptoms.

The Efficacy and Perioperative Complications Associated with Lumbar Spinal Fusion Surgery, Focusing on Geriatric Patients in the Republic of Korea

OBJECTIVE: The purpose of this study was to examine the efficacy and perioperative complications associated with lumbar spinal fusion surgery, focusing on geriatric patients in the Republic of Korea. METHODS: We retrospectively investigated 485 patients with degenerative spinal diseases who had lumbar spinal fusion surgeries between March 2006 and December 2010 at our institution. Age, sex, comorbidity, American Society of Anesthesiologists (ASA) class, fusion segments, perioperative complications, and outcomes were analyzed in this study. Risk factors for complications and their association with age were analyzed. RESULTS: In this study, 81 patients presented complications (16.7%). The rate of perioperative complications was significantly higher in patients 70 years or older than in other age groups (univariate analysis, p=0.015; multivariate analysis, p=0.024). The perioperative complications were not significantly associated with the other factors tested (sex, comorbidity, ASA class, and fusion segments). Post-operative outcomes of lumbar spinal fusion surgeries for the patients were determined on the basis of MacNab's criteria (average follow up period : 19.7 months), and 412 patients (85.0%) were classified as having "excellent" or "good" results. CONCLUSION: Increasing age was an important risk factor for perioperative complications in patients undergoing lumbar spinal fusion surgery, whereas other factors were not significant. However, patients' satisfaction or return to daily activities when compared with younger patients did not show much difference. We recommend good clinical judgment as well as careful selection of geriatric patients for lumbar spinal fusion surgery.

Giant Cystic Cerebral Cavernous Malformation with Multiple Calcification: Case Report

Cerebral cavernous malformation with giant cysts is rare and literature descriptions of its clinical features are few. In this case study, the authors describe the clinical symptoms, radiological findings, and pathological diagnosis of cerebral cavernous malformations with giant cysts, reviewing the relevant literature to clearly differentiate this from other disease entities. The authors present a case of a 19-year-old male with a giant cystic cavernous malformation, who was referred to the division of neurosurgery due to right sided motor weakness (grade II/II). Imaging revealed a large homogenous cystic mass, 7.2x4.6x6 cm in size, in the left fronto-parietal lobe and basal ganglia. The mass had an intra-cystic lesion, abutting the basal portion of the mass. The initial diagnosis considered this mass a glioma or infection. A left frontal craniotomy was performed, followed by a transcortical approach to resect the mass. Total removal was accomplished without post-operative complications. An open biopsy and a histopathological exam diagnosed the mass as a giant cystic cavernous malformation. Imaging appearances of giant cavernous malformations may vary. The clinical features, radiological features, and management of giant cavernous malformations are described based on pertinent literature review.

Comparison of Posterior Fixation Alone and Supplementation with Posterolateral Fusion in Thoracolumbar Burst Fractures

OBJECTIVE: We compared the radiological and clinical outcomes between patients who underwent posterior fixation alone and supplemented with fusion following the onset of thoracolumbar burst fractures. In addition, we also evaluated the necessity of posterolateral fusion for patients treated with posterior pedicle screw fixation. METHODS: From January 2007 to December 2009, 46 consecutive patients with thoracolumbar burst fracture were included in this study. On the basis of posterolateral fusion, we divided our patients into the non-fusion group and the fusion group. The radiological assessment was performed according to the Cobb's method, and results were obtained at immediately, 3, 6, 12 months after surgery. The clinical outcomes were evaluated using the modified Mcnab criteria at the final follow-up. RESULTS: The demographic data and the mean follow-up period were similar between the two groups. Patients of both groups achieved satisfactory clinical outcomes. The mean loss of kyphosis correction showed that patients of both groups experienced loss of correction with no respect to whether they underwent the posterolateral fusion. There was no significant difference in the degree of loss of correction at any time points of the follow-up between the two groups. In addition, we also compared the effect of fixed levels (i.e., short versus long segment) on loss of correction between the two groups and there was no significant difference. There were no major complications postoperatively and during follow-up period. CONCLUSION: We suggest that posterolateral fusion may be unnecessary for patients with thoracolumbar burst fractures who underwent posterior pedicle screw fixation.

The Role of Hyperthyroidism as the Predisposing Factor for Superior Sagittal Sinus Thrombosis

Superior sagittal sinus thrombosis (SSST) is an uncommon cause of stroke, whose symptoms and clinical course are highly variable. It is frequently associated with a variety of hypercoagulable states. Coagulation abnormalities are commonly seen in patients with hyperthyroidism. To the best of our knowledge, there are few reports on the association between hyperthyroidism and cerebral venous thrombosis. We report on a 31-year-old male patient with a six-year history of hyperthyroidism who developed seizure and mental deterioration. Findings on brain computed tomography (CT) showed multiple hemorrhages in the subcortical area of both middle frontal gyrus and cerebral digital subtraction angiography (DSA) showed irregular intra-luminal filling defects of the superior sagittal sinus. These findings were consistent with hemorrhagic transformation of SSST. Findings on clinical laboratory tests were consistent with hyperthyroidism. In addition, our patient also showed high activity of factors IX and XI. The patient received treatment with oral anticoagulant and prophylthiouracil. His symptoms showed complete improvement. A follow-up cerebral angiography four weeks after treatment showed a recanalization of the SSS. In conclusion, findings of our case indicate that hypercoagulability may contribute to development of SSST in a patient with hyperthyroidism.

Posterior Epidural Migration of Lumbar Disc Fragment: Three Cases and Review of Literature

We have experienced three unusual cases of dorsal extradural lumbar disc sequestration, manifesting as severe low back pain, radiating leg pain and motor weakness. Magnetic resonance imaging suggested sequestrated disk fragment located in epidural space had compressed the dural sac from lateral to dorsal sides. With the help of adequate early surgery by open procedure, these symptoms were relieved without any complications.

Comparative Study of Posterior Lumbar Interbody Fusion via Unilateral and Bilateral Approaches in Patients with Unilateral Leg Symptoms

OBJECTIVE: We investigated the clinical and radiological advantages of unilateral laminectomy in posterior lumbar interbody fusion (PLIF) procedure comparing with bilateral laminectomy, under the same procedural condition including bilateral instrumentation and insertion of two cages, in patients with degenerative lumbar disease with unilateral leg symptoms. METHODS: We retrospectively reviewed 124 consecutive cases of PLIF via unilateral or bilateral approach between January 2006 and April 2010. In 80 cases (bilateral group), two cages were inserted via bilateral laminectomy, and in 44 cases (unilateral group), via unilateral laminectomy. The average follow-up duration was 29.5 months. The clinical outcomes were evaluated with the Visual Analogue Scale (VAS) and the Oswestry disability index (ODI). The fusion rates and disc space heights were determined by dynamic standing radiographs and/or computed tomography. Operative times, intra-operative and post-operative blood losses and hospitalization periods were also evaluated. RESULTS: In clinical evaluation, the VAS and ODI scores showed excellent outcomes in both groups. There were no significant differences in term of fusion rate, but the perioperative blood loss and the operative time of the unilateral group were lower than that of the bilateral group. CONCLUSION: Unilateral laminectomy can minimize the operative time and perioperative blood loss in PLIF procedure. However, the different preoperative disc height between two groups is a limitation of this study. Despite this limitation, solid fusion and satisfactory symptomatic improvement could be achieved uniquely by our surgical method. This surgical method can be an alternative surgical technique in patients with unilateral leg pain.

Comparison of Fusion with Cage Alone and Plate Instrumentation in Two-Level Cervical Degenerative Disease

OBJECTIVE: This study assessed the efficacy of anterior cervical discectomy and fusion (ACDF) with cage alone compared with ACDF with plate instrumentation for radiologic and clinical outcomes in two-level cervical degenerative disease. METHODS: Patients with cervical degenerative disc disease from September 2004 to December 2009 were assessed retrospectively. A total of 42 patients received all ACDF at two-level cervical lesion. Twenty-two patients who underwent ACDF with cage alone were compared with 20 patients who underwent ACDF with plate fixation in consideration of radiologic and clinical outcomes. Clinical outcomes were assessed using Robinson's criteria and posterior neck pain, arm pain described by a 10 point-visual analog scale. Fusion rate, subsidence, kyphotic angle, instrument failure and the degenerative changes in adjacent segments were examined during each follow-up examination. RESULTS: VAS was checked during each follow-up and Robinson's criteria were compared in both groups. Both groups showed no significant difference. Fusion rates were 90.9% (20/22) in ACDF with the cage alone group, 95% (19/20) in ACDF with the plate fixation group (p = 0.966). Subsidence rates of ACDF with cage alone were 31.81% (7/22) and ACDF with plate fixation were 30% (6/20) (p = 0.928). Local and regional kyphotic angle difference showed no significant difference. At the final follow-up, adjacent level disease developed in 4.54% (1/22) of ACDF with cage alone and 10% (2/20) of ACDF with plate fixation (p = 0.654). CONCLUSION: In two-level ACDF, ACDF with cage alone would be comparable with ACDF with plate fixation with regard to clinical outcome and radiologic result with no significant difference. We suggest that the routine use of plate and screw in 2-level surgery may not be beneficial.

The Angiographic Feature and Clinical Implication of Accessory Middle Cerebral Artery

OBJECTIVE: Although there are several descriptions of this vessel, there is no detailed angiographic study of the accessory middle cerebral artery (AMCA) in Korea. We describe the angiographic characteristics of the cortical territory and origin of AMCA and discuss the clinical significance of this anomaly. METHODS: We searched for patients with AMCAs from a retrospective review of 1,250 conventional cerebral angiograms. We determined the origins, diameters and cortical territories of these AMCAs. RESULTS: Fifteen patients (15 of 1250 = 1.2%) had 16 AMCAs (one patient had bilateral AMCAs). AMCAs originated from the distal A1 in eleven cases, middle A1 in two, proximal A1 in two, and proximal A2 in one case. All AMCAs followed a course parallel to the main middle cerebral artery (MCA). All but three of these arteries were smaller than the main MCA. Thirteen of the smaller diameter AMCAs had cortical distribution to the orbito-frontal and prefrontal, and precentral areas. Three AMCAs had diameter as large as the main MCA. These three supplied the orbitofrontal, prefrontal, precentral, central and anterior-parietal arteries. CONCLUSION: The AMCAs originated from A1 or A2. Most had smaller diameter than the main MCA. The AMCAs coursed along the horizontal portion of the MCA, but supplied the orbital surface, the anterior frontal lobe and sometimes wider cortical territory, including the precentral, central, anterior-parietal areas.

Quality Control of Radiation Dosimetry Service / 의학물리

We have developed standards based on international criterions for the quality control of dose tested by the measurement institutions of individual exposure doses through improving the reliability of data on the exposure dose of individuals working in radioactive environment and securing the accuracy and reliability of individual dose measurements. Laws related to radiation dose applied to domestic institutions refer to ANSI N13.11?1993, but currently , in U.S. and some other countries the measurement of radiation doses is based on ANSI N13.11?2001 that reduced test categories and tightened the standards. We made efforts to simplify the standards and to reduce the number of dosimeters required in experiment, and avoided preventing or hindering the use of future technologies not approved under the current law such as glass dosimeter and optical stimulation dosimeter. The Quality Management Manual of Radiation Dosimetry Service, Assessment Manual of Radiation Dosimetry Service Accreditation Program, and the Personnel Dosimetry Performance-Criteria for Testing are documents applicable in supervising laboratories.

Primary Malignant Melanoma of the Cervical Spinal Nerve Root: A Case Report

Primary malignant melanoma of the nervous system is a rare disease, and accounts for only 1% of melanoma cases. Primary melanomas on the spinal nerve root, particulary the cervical spinal nerve root, are extremely rare. Only a few cases of primary melanoma arising from the spinal nerve root have been reported. We report our experience with a case of primary malignant melanoma of the cervical spinal nerve root.

Time to Recover Consciousness in Patients with Diffuse Axonal Injury : Assessment with Reference to Magnetic Resonance Grading

OBJECTIVE: This study was conducted to investigate the correlation between the degrees of injury on brain magnetic resonance imaging (MRI) and the time interval to recovery of consciousness in patients with diffuse axonal injury. METHODS: From January 2004 to December 2008, 25 patients with diffuse axonal injury were treated at our hospital. We retrospectively investigated the patients' medical records and radiological findings. We divided the patients into three groups according to the grade of MRI finding : grade I, small scattered lesions on the white matter of the cerebral hemisphere; grade II, focal lesions on the corpus callosum; and grade III, additional focal lesions on the brain stem. RESULT: Seven patients belonged to the grade I group; 10 to the grade II group; and 8 to the grade III group. The mean Glasgow Coma Scale (GCS) score of all patients at the time of admission was 7.28. Recovery of consciousness was observed in 23 of the 25 patients; the remaining two patients never regained consciousness. The time interval to recovery of consciousness (awake status) ranged from 1 day to 125 days (mean 22.1 days) : grade I group patients, within approximately 1 week (mean 3.7 days); grade II group patients, within approximately 2 weeks (mean 12.5 days); and grade III group patients, within approximately 2 months (mean 59.5 days). CONCLUSION: Our study results suggest a correlation between the mean time interval to recovery of consciousness in patients with diffuse axonal injuries and the degrees of brain injuries seen on MRI. Patients with grade I and II diffuse axonal injuries recovered consciousness within 2 weeks, while patients with grade III injuries required approximately 2 months.

Spontaneous Spinal Epidural Hematoma

Spontaneous spinal epidural hematoma (SSEH) is a relatively rare but significant spinal condition. Urgent surgical evacuation of a hematoma is generally indicated to prevent serious permanent neurological deficits. We encountered three cases of spontaneous spinal epidural hematomas associated with motor weakness that were treated successfully by surgical intervention.

Extraordinarily Long-Term Posttraumatic Cerebrospinal Fluid Fistula

Most posttraumatic cerebrospinal fluid (CSF) leakage is noticed by the patients with the first symptom, rhinorrhea. A 38-year-old woman presented with frequent clear continuous rhinorrhea and otorrhea for 5 years after basilar skull fracture. After this, meningitis was developed with subsequent CSF fistula. Her clinical symptom was improved by medical treatment. The dural defect and CSF leakage were not detected by computerized tomography (CT) cisternography. We report a rare case of persistent posttraumatic CSF fistula that continued for five years.

Clinical Analysis of Postoperative Outcome in Elderly Patients with Lumbar Spinal Stenosis

OBJECTIVE : The purpose of this study was to evaluate the efficacy and safety of the surgical treatment for lumbar spinal stenosis in elderly patients. METHODS : The authors reviewed the medical records of 49 patients older than 65 years of age with lumbar spinal stenosis who underwent surgical treatment from January 2002 to December 2004 in our institute. RESULTS : Average age of patients was 70 years old (32 women, 17 men). Twenty-four patients had chronic medical disorders. All patients were operated under the general anesthesia of these, 29 patients underwent decompressive laminectomy and decompressive laminectomy with instrumentation and fusion in 20 patients. The mean operation time was 193.5 minutes, mean estimated blood loss was 378cc and mean postoperative hospital stay length was 15.3 days. The mean follow-up duration was 11.9 months. The evaluation of outcome was assessed by Macnab classification. At first month after operation, the outcome showed excellent in 7 (14.3%), good in 35 (71.4%), fair in 5 (10.2%), and poor in 2 (4.1%). And at 6 months after operation, 17 patients were lost in follow-up, the outcome showed excellent in 4 (12.5%), good in 25 (78.1%), fair in 3 (9.4%), and no poor cases. There was no significant difference between outcome of laminectomy alone and that of laminectomy with fusion. Six patients (12.2%) experienced postoperative complications which included wound infection (3), nerve root injury (1), disc herniation (1), and reoperation due to insufficient decompression (1). There were no deaths related to operation. CONCLUSION : We conclude that the surgical treatment for lumbar spinal stenosis in elderly patients can provide good results with acceptable morbidity when carefully selected. In addition, decision on lumbar spinal fusion should not be against solely on advanced age.

The Incidence and Clinical Significance of Fenestrations in the Horizontal Segment of the Anterior Cerebral Artery Detected by Conventional Angiography and Magnetic Resonance Angiography

OBJECTIVE: We examined the incidence of fenestration in the proximal segment of the anterior cerebral artery(ACA) and reviewed its clinical significance. METHODS: Cerebral angiography was performed in 843 patients and magnetic resonance angiography(MRA) in 1,787; all patients had, or were suspected to have, cerebrovascular disease. We subsequently reviewed the angiography and MRA data. RESULTS: Fourteen patients (six men and eight women, 35~81 years of age, median age = 67 years) had proximal ACA fenestrations. Three of the 843 patients (0.36%) undergoing cerebral angiography had fenestrations of proximal ACA as did eleven of the 1,787 MRA patients (0.62%). Seven fenestrations were located on the right side and seven fenestrations were located on the left side. The fenestrated ACA in one patient was associated with a saccular aneurysm at its proximal end. None of the 120 patients who underwent both conventional cerebral angiography and cranial MRA showed fenestration of proximal ACA. CONCLUSION: Although fenestration of ACA has little clinical significance, knowledge and recognition of this condition is important in the interpretation of cerebral images, especially during neurosurgical procedures.

Fenestration and Duplication of the Vertebrobasilar Artery Detected by Conventional Angiography and Magnetic Resonance Angiography

OBJECTIVE: The purpose of our study is to examine the clinical significance of vertebrobasilar artery(VBA) fenestration and duplication. In addition, we review its incidence and pathogenesis. METHODS: Cerebral angiography was performed in 803 patients and magnetic resonance angiography(MRA) in 880; the patients had or were suspected to have cerebrovascular disease. We retrospectively reviewed angiography and MRA. RESULTS: Fifteen patients (eight men, seven women, 3 to 77 years of age, median age = 58 years) had a VBA fenestration and duplication. Seven (7/803 = 0.87%) of the patients undergoing cerebral angiography revealed fenestrations and one duplication of VBA. Ten patients (10/880 = 1.14%) among 880 patients that underwent MRA demonstrated fenestration of basilar artery(BA). Two of 66 patients that underwent both conventional cerebral angiography and cranial MRA showed a fenestration of BA. Twelve fenestrations were located in the proximal portion of the BA and one was in the mid portion of the BA. One vertebral artery(VA) fenestration was located in the intracranial portion of the right VA, and one VA duplication was at the level of C1-2 in the left VA. CONCLUSION: In addition to medial defects, flow phenomena at the proximal end of fenestrations, where hemodynamic stress and increased turbulence are present, may contribute to aneurysm formation. And arterial fenestration is a predisposing factor in vascular injury and cerebral ischemia.

Persistent Trigeminal Artery Detected by Conventional Angiography and Magnetic Resonance Angiography

OBJECTIVE: A persistent trigeminal artery (PTA) may be found incidentally on conventional cerebral angiography and magnetic resonance(MR) angiography. Our goal is to examine the course and relationships of the vessel to the surrounding structures. METHODS: Cerebral angiography was performed in 494 patients and MRA in 880; the patients had or were suspected to have cerebrovascular disease. In the images, the incidence, origin, course, and relationships of the PTA were evaluated. RESULTS: A PTA was found in two (0.4%) of the patients undergoing cerebral angiography and three (0.34%) receiving an MR angiography. In four patients, the PTA arose from the lateral part of the cavernous segment of the internal carotid artery, then passed caudally and around the base of the dorsum sellae. In the other patient, the PTA arose from the medial aspect of the siphon, and ascended sharply to pierce the dorsum sellae and join the basilar artery. In four cases, there was hypoplasia of a proximal basilar artery below the abnormal communication; the vessel was of increased diameter above the communication. CONCLUSION: Identification of a PTA with a trans-sellar course is crucial if trans-sphenoidal surgery is planned. Hypoplasia of a proximal basilar artery should not be mistaken for an acquired narrowing.