Proper Management of Posttraumatic Tension Pneumocephalus / 대한신경손상학회지

Pneumocephalus is commonly seen after craniofacial injury. The pathogenesis of pneumocephalus has been debated as to whether it was caused by ball valve effect or combined episodic increased pressure within the nasopharynx on coughing. Discontinuous exchange of air and cerebrospinal fluid due to “inverted bottle” effect is assumed to be the cause of it. Delayed tension pneumocephalus is not common, but it requires an active management in order to prevent serious complication. We represent a clinical case of a 57-year-old male patient who fell down from 3 m height, complicated by tension pneumocephalus on 5 months after trauma. We recommend a surgical intervention, but the patient did not want that so we observe the patient. The patient was underwent seizure and meningitis after 7 months after trauma, he came on emergency room on stupor mentality. Tension pneumocephalus may result in a neurologic disturbance due to continued air entrainment and it significantly the likelihood of intracranial infection caused by continued open channel. Tension pneumocephalus threat a life, so need a neurosurgical emergency surgical intervention.

Hinge Fracture during Cervical Open-door Laminoplasty: Does it Affect Clinical and Radiographic Outcomes?

OBJECTIVE: The purpose of this study was to determine whether the status of the hinge gutter affected clinical and radiographic outcomes of cervical open door laminoplasty. METHODS: We retrospectively analyzed 43 patients who had undergone cervical open door laminoplasty. 23 CT scans were performed at 2 days post-operation. The number of CT scans at 3, 6, 12 and 24 months were 16, 12, 21 and 11, respectively. We collected perioperative and follow-up data, including clinical and radiographic results. RESULTS: There were 7 patients without a hinge fracture and 16 patients with one or more hinge fractures at 2 days postoperation. There were 90 hinges, and the rate of ideal greenstick deformation of the hinge was 63% on 2-day-postoperative CT scans. Postoperative VAS scores of neck pain (p=0.012) in patients without a hinge fracture were higher than in patients with hinge fractures. The hinge healing rates were 37% at 3 months, 57.4% at 6 months, 86.4% at 12 months, and 85.4% at 24 months. Among the patients, 14 patients had healed hinges, and 7 patients had one or more hinge(s) that was/were not healed at 12 months post-operation. However, in clinical and radiographic outcomes, there was no difference between these patients. CONCLUSION: Cervical open door laminoplasty was safe and provided stable reconstruction of laminar expansion. In radiographs, the difference between hinges that had healed and hinges that had not healed was statistically negligible. Hinge fractures might not influence the clinical and radiographic outcomes of cervical open door laminoplasty.

Brain Metastases of Papillary Thyroid Carcinoma with Horner's Syndrome

Papillary thyroid carcinoma (PTC) is the most common type of thyroid malignancy and has relatively favorable prognosis. Blood-borne metastases of PTC are very rare among the thyroid malignancies. Moreover a case of blood-borne central nervous system metastasized PTC with only unilateral Horner's syndrome, and without any abnormalities in laboratory or physical examinations has not been described before. A 53-year-old female patient had been managed in ophthalmologic clinic due to vague symptoms of right monocular blurred vision with eye dryness for 3 months, but showed no signs of improvement. So it was performed a magnetic resonance imaging and magnetic resonance angiography to evaluate the possibilities of cerebral lesion. And a left frontal mass was incidentally found, and the tumor turned out to be a PTC that had metastasized to brain, regional lymph node, cervical, thoracic spine, and lung. We describe a PTC with extraordinary initial symptoms that metastasized to an unusual site. We recommend that if a papillary thyroid tumor with unusual symptoms or at an advanced stage is found, further investigation should be performed for distant metastasis.

Erratum to "Prevalence and Epidemiological Features of Moyamoya Disease in Korea" (JCEN vol.14, no.2, 2012)

In the article, name of the first author, "Sang Hyuk Im", was printed mistakenly as "Sang Hyuk Yim" by negligence of the authors. Additionally, the correspondence author's address has been also corrected as follow at their request: Department of Neurosurgery, Catholic Neuroscience Center, Yeouido St. Mary's Hospital, College of Medicine, Catholic University, 82 Yeouido-dong, Yeongdeungpo-gu, Seoul, 150-713, Korea.

Analysis of Risk Factors for the Development of Post-Operative Epidural Hematoma after Intracranial Surgery / 대한신경손상학회지

OBJECTIVE: Patients undergoing intracranial operations often suffer from post-operative epidural hematoma (EDH). The incidence and risk factors for with the occurrence of EDH after intracranial operations are not well described previously. The objective of this study was to identify the risk factors and the incidence of post-operative EDH adjacent and regional to the craniotomy. METHODS: This was a retrospective study of 23 (2.4%) patients, between January 2005 and December 2011, who underwent epidural hematoma evacuation after primary intracranial during this period, 941 intracranial operations were performed. The control group (46 patients) and hematoma group (23 patients) were categorized on the basis of having undergone the same pre-operative diagnosis and treatment within 3 months of their operations. The ages of the hematoma and control group were individually matched to similar ages within 10 years of each other to minimize bias of age. RESULTS: Univariate analysis showed that the significant pre-operative and intra-operative factors associated with post-operative EDH were a pre-operative Glasgow Coma Scale (GCS) scored 1.0 (p=0.014), prothrombin time (PT) >11.3 sec (p=0.008), intra-operative blood loss >650 mL (p=0.003) and craniotomy size >7,420 mm2 (p=0.023). In multivariate analysis, intra-operative blood loss exceeding 650 mL (median of total patients) placed a patient at significantly increased risk for post-operative EDH. CONCLUSION: Recognizing the limitations of the study, large intra-operative blood loss, wide craniotomy area, prolonged PT and a pre-operative GCS <8 are presented implicated with an increased risk of post-operative EDH after intracranial surgery.

Prevalence and Epidemiological Features of Moyamoya Disease in Korea

OBJECTIVE: The objectives of the present study were to investigate the annual detection rate of patients with Moyamoya disease (MMD) and to describe the prevalence and epidemiological features of the Moyamoya patients in Korea. MATERIALS AND METHODS: The authors analyzed the epidemiological data of Korean patients taken from the National Health Insurance Corporation in Korea among Moyamoya patients who were treated from 2004 until 2008. RESULTS: Based on 2004 data, 2,539 MMD patients were treated in Korea and the prevalence rate was 5.2 per 100,000 people. There were 2,987 in 2005, 3,429 in 2006, 4,051 in 2007, and 4,517 cases in 2008, and the prevalence rates per 100.000 people were 6.3, 7.0, 8.6, and 9.1, for those respective years. This represents an annual increase of 15% of new cases during this period. In 2008, 466 people were newly diagnosed with MMD, representing an incidence rate of 1 per 100,000 persons. The gender ratio was 1,547 men (34%) and 2,970 women (66%). Women had a higher incidence rate than men (1.94 times). There were two age peaks: teenagers and those in their forties. CONCLUSION: The present study shows that the number of Moyamoya patients in Korea is increasing. This increase could partly be explained by a recent increase in newly diagnosed cases, suggesting that a more careful consideration of the disease and better diagnostic techniques should be promoted among clinicians.

Hemorrhagic Complications Induced by External Ventricular Draining Catheters / 대한뇌혈관외과학회지

BACKGROUND: External ventricular drainage (EVD) is one of the most frequently performed operative procedures in neurosurgery. A retrospective analysis was conducted for patients who underwent EVD to determine the incidence rate of post-procedural intracranial hemorrhage and to identify underlying risk factors. METHODS: Patients who underwent EVD between January 2003 and January 2011 were selected. Catheter-induced hemorrhage (CIH) was defined as any evidence of new hemorrhage on the post-procedural computerized tomography (CT) scan obtained within 24 hours of catheter insertion. The rate of hemorrhage was calculated, and the possible risk factors were statistically analyzed. RESULTS: The data of 229 patients were analyzed. Twenty-one patients developed CIH, for an incidence rate of 9.17%. The factors that increased the rate of CIH were age > or =60 years, bilateral catheter insertion, and pre-existing heart disease. The patients > or =60 years of age had a 2.8-fold increased risk of CIH. A history of heart disease contributed to a 20-fold increased risk of CIH (p or =60 years, bilateral catheter insertion, and a history of heart disease are the three most significant risk factors for CIH. Since these risk factors are not modifiable, all possible contributors should be considered to minimize the risk such as skilled maneuvers and techniques or high blood pressure.

Hemorrhagic Complications Induced by External Ventricular Draining Catheters / 대한뇌혈관외과학회지

BACKGROUND: External ventricular drainage (EVD) is one of the most frequently performed operative procedures in neurosurgery. A retrospective analysis was conducted for patients who underwent EVD to determine the incidence rate of post-procedural intracranial hemorrhage and to identify underlying risk factors. METHODS: Patients who underwent EVD between January 2003 and January 2011 were selected. Catheter-induced hemorrhage (CIH) was defined as any evidence of new hemorrhage on the post-procedural computerized tomography (CT) scan obtained within 24 hours of catheter insertion. The rate of hemorrhage was calculated, and the possible risk factors were statistically analyzed. RESULTS: The data of 229 patients were analyzed. Twenty-one patients developed CIH, for an incidence rate of 9.17%. The factors that increased the rate of CIH were age > or =60 years, bilateral catheter insertion, and pre-existing heart disease. The patients > or =60 years of age had a 2.8-fold increased risk of CIH. A history of heart disease contributed to a 20-fold increased risk of CIH (p or =60 years, bilateral catheter insertion, and a history of heart disease are the three most significant risk factors for CIH. Since these risk factors are not modifiable, all possible contributors should be considered to minimize the risk such as skilled maneuvers and techniques or high blood pressure.

Axial Neck Pain after Cervical Laminoplasty

OBJECTIVE: It has been demonstrated that cervical laminoplasty is an effective and safe method of treating multi-level cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament. However, recent reports have suggested that axial neck pain is frequently encountered after cervical laminoplasty. The aim of the present study was to determine clinical significance of the C7 spinous process on axial neck pain after cervical laminoplasty. METHODS: A total of 31 consecutive patients that underwent cervical laminoplasty between March 2002 and December 2008 were reviewed. The authors evaluated and compared axial neck pain and lordotic angle in patients that underwent C7 spinous process preserving surgery (group 1, n = 16) and in patients in which the C7 spinous process was sacrificed (group 2, n = 15). RESULTS: Severe or moderate early axial pain occurred in 56.2% of patients in group 1 and in 86.6% in group 2. Severe or moderate late axial pain occurred in 12.5% in group 1 and in 73.3% in group 2. Eighty-Six percent of patients in group 2 and 43% in group 1 experienced aggravation of their axial neck pain during the early postoperative period. Aggravation of axial neck pain during early postoperative period was less common in group 1 but not statistically significant (p = 0.073). Sixty-six percent of patients in group 2 and 12% in group 1 had aggravated axial neck pain at late postoperative period and aggravation of late axial neck pain was significantly less common in group 1 (p = 0.002). CONCLUSION: The present study demonstrates that C7 spinous process preserving laminoplasty decreases the incidence of aggravated axial neck pain after cervical laminoplasty.

Causative analysis of cases with permanent complication following extracranial-entracranial bypass surgery in patients with hemodynamic ischemia / 대한뇌혈관외과학회지

OBJECTIVE: Extracranial-intracranial(EC-IC) bypass procedures have proved to be useful and safe in selected patients for revascularization. We have performed EC-IC bypass procedures in 170 patients with atherosclerotic cerebral ischemia and moyamoya disease. We analyzed the cases that had permanent complications after performing EC-IC bypass procedures in these 170 patients. METHODS: We performed ECIC bypass surgery during the recent 10 years for augmenting the cerebral blood flow in 170 patients with atherosclerotic cerebral ischemia and moyamoya disease. Of the 170 patients, the pathologic lesions were atherosclerotic cerebral ischemia in 125 and moyamoya in 45. All the patients were symptomatic and in a hemodynamic cerebral ischemic state, as diagnosed by the acetazolamide loading test. Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis was performed in 158 cases and graft bypass with using the saphenous vein or radial artery was done in 12 cases. RESULTS: Of 170 patients who underwent bypass surgery, twenty four patients had postoperative neurologic deficits. Of these 24 patients, the neurologic deficits of 17 patients resolved completely within 3 weeks, but the remaining 7 patients (moyamoya in 5 patients and 2 patients were atherosclerotic) had permanent deficits. The probable causes of the permanent neurologic deficits were that bypass was done too soon after an ischemic attack or hemorrhage (3 cases), intracerebral steal phenomenon during anesthesia (2 case), postbypass thrombotic occlusion of the prebypass stenotic artery (1 case) and postbypass thromboembolism (1 case) CONCLUSION: Permanent neurologic deficits could complicate some cases following bypass surgery. The suggested causes of neurologic deficit were hypoperfusion and inappropriate CO2 tension in the blood and fluctuation of the blood pressure during the perioperative period. To prevent complications, maintain an appropriate perfusion pressure and blood pressure control and follow this with antiplatelet or anticoagulation therapy as soon as possible.

Stereotactic Radiosurgery with the CyberKnife for Pituitary Adenomas

OBJECTIVE: In recent years, CyberKnife has emerged as an important treatment modality in the management of pituitary adenomas. Treatment results after performing CyberKnife and the complications of this procedure are reviewed. METHODS: Twenty-six patients with pituitary adenomas received stereotactic radiosurgery with the CyberKnife (CKRS). The follow-up periods ranged from 7 months to 47 months (mean+/-SD : 30+/-12.7 months). The patients consisted of 17 with non-functioning adenomas, 3 with prolactinomas and 6 with acromegaly. The change in the tumor volume, visual acuity, hormonal function, and complications by this therapy were analyzed in each case. RESULTS: The tumor control rate was 92.3%. Hormonal function was improved in all of the 9 (100%) functioning adenomas. Hormonal normalization was observed in 4 of the 9 (44%) patients with a mean duration of 16 months. In two patients (7.6%), visual acuity worsened due to cystic enlargement of the tumor after CKRS. No other complications were observed. CONCLUSION: CyberKnife is considered safe and effective in selected patients with pituitary adenomas. However, longer follow-up is required for a more complete assessment of late toxicity and treatment efficacy.

Thalamic Deep Brain Stimulation for Writer's Cramp

Writer's cramp is a type of idiopathic focal hand dystonia characterized by muscle cramps that accompany execution of the writing task specifically. There has been renewed interest in neurosurgical procedures for the treatment of dystonia over the past several years. In particular, deep brain stimulation (DBS) has received increasing attention as a therapeutic option for patients with dystonia. However, to date, limited reporters made investigations into DBS in relation to the Writer's cramp. In this case, unilateral Ventro-oralis complex (Vo) DBS resulted in a major improvement in patient's focal dystonic movement disorders. Her post-operative Burke-Fahn-Marsden Dystonia Rating (BFMDR) scale demonstrated 1 compared with pre-operative BFMDR scale 4. We conclude that thalamic Vo complex DBS may be an important neurosurgical therapeutic option for Writer's cramp.

Effect of Direct Revascularization in Ischemic Type of Adult Moyamoya Disease / 대한뇌혈관외과학회지

OBJECTIVE: The authors evaluated the effects of direct revascularization (superficial temporal artery-middle cerebral artery bypass) in the prevention of further stroke, including recurrent ischemic event or bleeding in patients with ischemic type of adult moyamoya disease by clinical, pathophysiological and angiographical studies. MATERIALS AND METHODS: Twenty four patients who had ischemic symptoms in adult moyamoya disease were investigated. The mean age of the patients was 40.8 years. The follow up period ranged from 6 months to 8 years. In 24 patients who were surgically treated, thirty one sides (both sides in 7 patients) were performed to superficial temporal artery-middle cerebral artery anastomosis and dura splitting. RESULT: Average follow up period was 4.12 years. Perioperative and postoperative course was uneventful in 16 patients. 2 patients had new ischemic attack probably due to intracerebral steal phenomenon during operation, 6 patients had neurologic symptoms due to change of hemodynamic flow pattern after successful EC-IC bypass that included temporary neurologic deficit in 4, postbypass occlusion of the preoperative stenosis of anterior cerebral artery in one and focal seizure in one. Long term follow up results of 24 patients were showing major deficit in one and minor deficit in two. All patients experienced no further ischemic or hemorrhagic events during follow up period. In postoperative angiogram, drastic diminution of basal moyamoya vessels, which are supposed to be responsible for hemorrhage, was observed in 15 of 18 patients(83%) who were capable of postoperative 3-6 months follow up angiogram. CONCLUSION: In case of adult moyamoya disease, direct bypass surgery is particularly important on the prevention of recurrent ischemic or hemorrhagic events. And a decrease in basal moyamoya vessels was induced significantly by direct bypass surgery, which may reduce the expected risk of hemorrhage effectively. But direct bypass in moyamoya disease had operative morbidity in high frequence. So, moyamoya disease patients who undergo direct revascularization should be monitored carefully during the perioperative and postoperative period.

Changes of flow pattern after extracranial intracranial arterial bypass in patients with artherosclerotic cerebral ischemia and moyamoya disease / 대한뇌혈관외과학회지

OBJECTIVE: Extracranial-intracranial arterial bypass (EIAB) has proved to be useful in selected patients with artherosclerotic cerebral ischemia and moyamoya disease. But neurological deterioration (ND) after EIAB has occasionally been reported in spite of successful EIAB. We have performed EIAB in 150 patients with artherosclerotic cerebral ischemia and moyamoya disease during the recent 8 years. We analyzed the patients who exhibited ND after successful EIAB was performed for a selected group of patients with artherosclerotic cerebral ischemia and moyamoya disease. METHODS: Among 150 patients, the cause of the hemodynamic ischemia was atherosclerotic in 90 and moyamoya disease in 60. Eighteen patients experienced ND after successful EIAB. There were 14 patients with temporary neurologic deficit and 5 patients had a permanent deficit. We divided these 18 patients into two groups. Group 1 revealed relative hyperperfusion of a chronically hypoperfused area of the brain after successful EIAB. Group 2 showed hypoperfusion of the brain by the change of the flow pattern after successful EIAB. RESULTS: Of the 18 patients who experienced ND after successful EIAB, 8 patients belonged to group 1 and 10 patients belonged to group 2. We divided group II into four subgroups according to angiographic flow patterns. The first subgroup (2 patients) showed delayed filling of one division out of two divisions of the middle cerebral artery. The second subgroup (3 patients) showed collision between the orthograde flow and the retrograde flow from the grafted vessel, which resulted in more profound hypoperfusion. The third subgroup (2 patients) exhibited a complete occlusion of the preoperative stenotic artery. The fourth subgroup (3 patients) included the cases with marginal hypoperfusion in the periphery of the perfused region from the grafted extracranial artery. CONCLUSION: EIAB is a reliable, reasonably safe method for establishing new pathways of collateral circulation to the brain. However, this operation can have potential complications according to the relative hyperperfusion or hypoperfusion that's due to the altered flow pattern after the bypass.

Primary Occipital Malignant Melanoma

Primary intracranial melanoma is uncommon. These tumors most commonly occur at the temporal lobe, cerebellum and cerebellopontine angle. We report a case of intracranial malignant melanoma of the occipital lobe in a 60-year-old man who presented with headache and visual disturbance. The mass showed hyperintensity on T1-weighted images and hypointensity on T2-weighted magnetic resonance images. He underwent gross total removal of tumor and received radiotherapy. Followup imaging studies showed neither recurrence nor any signs of residual disease for 4 months.

Effect of Direct Bypass on the Prevention of Hemorrhage in Patients with the Hemorrhagic Type of Moyamoya Disease / 대한뇌혈관외과학회지

OBJECTIVE: The authors evaluated the effect of direct bypass (superficial temporal artery-middle cerebral artery bypass) in the prevention of rebleeding episodes in patients suffering from hemorrhagic moyamoya disease by comparing this method with indirect bypass. METHODS: Fifteen patients who had hemorrhagic moyamoya without aneurysm comprised the study group. The mean age of patients was 44.4 years and follow up period ranged from 0.8 to 7.1 years (mean; 3.61 years). Revascularization surgery was performed in 21 sides in 15 patients. Direct bypass was performed in 17 sides and indirect bypass in the other 4 sides. RESULTS: During the follow-up period after the revascularization surgery, three sides (14.3%) of the 21 sides presented with rebleeding episode, one of 17 sides (mean follow-up periods; 2.94 years) treated with direct method and 2 of 4 sides (mean follow-up periods; 6.45 years) treated with indirect method. Kaplan-Meier analysis of rebleedingfree survival showed quite different between direct and indirect method but statistically insignificant (p=0.0541). CONCLUSION: Direct bypass may reduce the risk of hemorrhage more effectively than indirect bypass. However, direct bypass cannot always prevent rebleeding.

Orbital Infarction Syndrome after Surgery for Ruptured Anterior Communicating Artery Aneurysm: Case Reports / 대한뇌혈관외과학회지

Orbital infarction syndrome is a rare complication of neurosurgical procedures. The authors recently experienced two patients suffered from acute proptosis, ophthalmoplegia, and blindness developed immediately after surgery for ruptured anterior communicating artery aneurysms. Both patients underwent standard frontotemporal craniotomies to clip their aneurysms. Retinal and choroidal nonperfusion, and ophthalmoplegia, which suggested hypoperfusion of the ophthalmic artery and its branches, consistent with the orbital infarction. We report two cases of orbital infarction syndrome and discuss possible mechanism with literature review.

Autologous Bone Marrow Stem Cell Transplantation for Neuronal Regeneration after Extracranial-Intracranial Bypass Surgery in Patients with Cerebral Infarction: Preliminary Report / 대한뇌혈관외과학회지

INTRODUCTION: Adult stem cells generate differentiated cells beyond their own tissue boundaries. To prove that stem cells derived from bone marrow is capable of therapeutic application in cerebral ischemic patients, we performed this study. MATERIAL AND METHOD: We transplanted adult stem cells derived from bone marrow of the patient's iliac bone to 5 patients with cerebral infarction. Of 5 patients, two patients had internal carotid artery occlusion, two patients had severe stenosis of the middle cerebral artery, remaining one patient had occlusion of the branch of the middle cerebral artery. At first, we performed extracranial-intracranial bypass surgery in all patients, and then implanted bone marrow stem cell in the infarcted brain and boder zone area directly under the microscopic navigator and also injected bone marrow stem cells through the grafted vessel to the infarcted area. Two weeks after bypass surgery, we confirmed the patency of bypass graft with external carotid angiography. In the same setting, mesenchymal stem cells acquired from autologous bone marrow were superselectively injected into the bypass graft via a microcatheter. Postoperative evaluation of the patients was decided to the neurological status and the degree of reduction of the high signal area on the T2 image of the postoperative MRI. RESULT: All patients who underwent bypass surgery with stem cell implantation had an uneventful postoperative course and showed some improvement of preoperative neurologic dysfunction. Postoperative significant improvement of cerebral vasoreactivity to acetazolamide was showed in all patients. On postoperative 3 months MRI, three patients showed significant reduction of the high signal area on the T2 image, and also improved neurological status on those patients. Other one patient showed moderate degree of the reduction of the high signal area on T2 image of the postoperative MRI, but neurological status of that patient slightly improved. Remaining one patient who showed poor circulation via bypass graft does neither reduction of the high signal area on T2 image of the postoperative MRI nor improvement of the neurological status of that patient. CONCLUSION: In patients of fixed cerebral infarction with major neurologic deficit, EC-IC bypass surgery is not effective, even though infarcted area filled by grafted vessel extensively. In those patients, autologous bone marrow stem cell implantation combined with bypass seems to be expect neuronal regeneration.

Complications of Extracranial-Intracranial Bypass Surgery / 대한뇌혈관외과학회지

OBJECTIVES: Extracranial-intracranial (EC-IC)bypass procedures have proved useful in selected patients with cerebral ischemia. We have experienced EC-IC bypass procedures in 85 patients with hemodynamic cerebral ischemia, moya moya and complicated aneurysm. In this study, complications after EC-IC bypass procedures was investigated. METHODS: Authors performed EC-IC bypass surgery for augmentation of cerebral blood flow in 85 patients for recent 7 years. Of 85 patients, the pathologic lesions were artherosclerotic hemodynamic cerebral ischemia in 60, moya moya in 14, complicated aneurysm in 9, and traumatic occlusion of the carotid artery in 2. An superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis was performed in 67 cases and graft bypass with saphenous vein or radial artery in 18 cases. RESULTS: Of 85 patients who underwent bypass surgery, 63 had an uneventful postoperative course. Fifteen patients had hyperperfusion syndrome that included temporary neurologic deficit in 7, reperfusion hemorrhage in 3, seizure in 3, and neusea and vomiting in 2. Five patients had wound problems. Permanant neurologic deficit and complete obstruction of the preoperative stenotic lesion occured in one respectively. All patients except three cases of reperfusion hemorrhage and one case of permanent neurologic deficit recovered completely. Two of three cases of reperfusion hemorrhage and one case of permanent neurologic deficit recovered with minor neurologic deficit, and the remaining one case of reperfusion hemorrhage died. CONCLUSION: EC-IC bypass surgery is a reliable and reasonably safe method for establishing new pathways of collateral circulation to the brain. However, this operation can have potential complications by relative hyperperfusion of chronically hypoperfused and presumably dysautoregulated region, and new flow pattern after bypass. Bypass is deferred to 8 weeks till impaired autoregulation is restored after acute cerebral infarction. And blood pressure should be controlled closely throughout the immediate postoperative period.

Effectiveness of Bypass Surgery in Treatment and Prevention for Cerebrovascular Occlusive Disease

To study the effect of extracranial-intracranial(EC/IC) bypass on symptomatic patients with hemodynamic cerebral ischemia, we prospectively reviewed 76 patients who underwent EC/IC bypass surgery in patients with occlusive cerebrovascular disease. A series of 76 patients treated in a 7 years period met following criteria. (1) symptomatic internal carotid artery(ICA) or middle cerebral artery(MCA) obstruction or stenosis over 80%. (2) decrease in basal cerebral blood flow(CBF) over 10%. (3) decreased reactivity of CBF in response to acetazolamide. Among these, the types of ischemic episodes were transient ischemic attack(TIA) or reversible ischemic neurological deficit(RIND) in 39, minor stroke in 22, and major stroke in 15. Based on our criteria, superficial temporal artery(STA)-MCA anastomosis was performed in 67 cases and EC-IC bypass grafting using saphenous vein or radial artery in 9. Average follow up period was 26 months(3 months~7 year). Patency of bypass was confirmed by postoperative angiography or magnetic resonence angiography(MRA) in all case except four cases. Of the 72 patients with patiency of bypass, 68 patients(94%) have had an excellent to good outcome with improvement of preoperative neurologic or cognitive dysfunction, 3 patients showed no improvement of preoperative neurologic symptoms and remaining one patient had new developed deficit. All 72 patients with patency of bypass had experienced no further cerebral ischemic events during following period. Postoperative significant improvement of CBF to acetazolamide was showed in 68 cases(94%) of the 72 cases with patency of bypass, while the basal CBF showed significant improved in 31cases. Postoperative permanent neurologic deficit occurred only in one. In view of these finding, the author suggest that EC-IC bypass surgery is a reliable and resonably safe method for establishing new pathways of collateral circulation to the brain and to be considered as an appropriate therapy for improvement of the cerebrovascular reserve capacity in patients with hemodynamic cerebral ischemia, defined using the strict selection criteria employed in this study.