A Ruptured lenticulostriate artery aneurysm in moyamoya disease treated with Onyx embolization

Lenticulostriate artery (LSA) aneurysms are uncommon. Here, we report one case of ruptured LSA aneurysm which is related to Moyamoya disease (MMD). Surgical treatment of this aneurysm is challenging because of its deep location and complex neural structures around the LSA. We report one case treated with endovascular Onyx embolization, successfully and review LSA aneurysm associated with MMD.

Pre- and Post-Angioplasty Perfusion CT with Acetazolamide Challenge in Patients with Unilateral Cerebrovascular Stenotic Disease

OBJECTIVE: Perfusion computed tomography (PCT) has the ability to measure quantitative value and produce maps of mean transit time (MTT), cerebral blood flow (CBF), and cerebral blood volume (CBV). We assessed cerebral hemodynamics by using these parameters and acetazolamide (ACZ) challenge for pre- and post-procedural evaluation in patients with unilateral cerebrovascular stenotic disease. METHODS: Thirty patients underwent pre-procedural PCT with ACZ challenge, and 24 patients (80%) was conducted follow up PCT after angioplasty with same protocol. The mean MTT, CBF, and CBV were measured and compared in both middle cerebral arterial (MCA) territories before and after ACZ challenge. Hemispheric ratio and percent change after ACZ challenge were calculated before and after angioplasty. RESULTS: The mean stenosis rate was 76.6%. Significant increases in MTT (32.6%, p=0.000) and significant decreases in CBF (-14.2%, p=0.000) were found in stenotic side MCA territories. After ACZ challenge, there were significant changes in MTT (37.4%, p=0.000), CBF (-13.1%, p=0.000), and CBV (-10.5%, p=0.001) in pre-procedural perfusion study. However, no significant increases were found in MTT, or decreases in CBF and CBV in post-procedural study. There were no significant changes after ACZ challenge also. In addition, the degrees of these changes (before and after ACZ challenge) were highly correlated with the stenotic degrees in pre-procedural perfusion study. CONCLUSION: PCT with ACZ challenge appears to be a useful tool to assess the cerebral perfusion status especially in patients with unilateral symptomatic stenotic disease.

Anatomic Consideration of the C1 Laminar Arch for Lateral Mass Screw Fixation via C1 Lateral Lamina : A Landmark between the Lateral and Posterior Lamina of the C1

OBJECTIVE: To clarify the landmark for deciding the entry point for C1 lateral mass screws via the posterior arch by using 3-dimensional (3D) computed images. METHODS: Resnick insisted that the C1 posterior arch could be divided into pure posterior and lateral lamina (C1 pedicle). Authors studied where this transition point (TP) is located between the posterior lamina and the C1 pedicle and how it can be recognized. The 3D computed images of 86 cadaver C1s (M : F=45 : 41) were used in this study. RESULTS: The superior ridge of the C1 posterior arch had 2 types of orientation. One was in the vertical direction in the C1 posterior lamina and the other was in the horizontal direction in the C1 pedicle. The TP was located at the border between the 2 areas, the same site as the posterior end of the groove of the vertebral artery. On posterior-anterior projection, the posterior arch was sharpened abruptly at TP. We were unable to identify the TP in 6.4% of specimens due to complete or partial osseous bridges. A total of 93.8% of the TP were located between the most enlarged point of the spinal canal and the medial wall of the vertebral artery. CONCLUSION: The anatomic entry zone of C1 lateral laminar screws was clarified and identified based on the TP by using preoperative 3D computed images.

Bilateral Superior Cerebellar Artery Infarction after Stent-Angioplasty for Internal Carotid Artery Stenosis

Spontaneous bilateral cerebellar infarction in the territory of the superior cerebellar arteries is extremely rare. Occasionally there have been reports of bilateral cerebellar infarction due to vertebrobasilar atherosclerotic occlusion or stenosis, whereas no report of bilateral cerebellar infarction due to complicated hemodynamic changes. In this report, we present a patient with bilateral cerebral infarctions related to stenoses of bilateral internal carotid arteries, in whom vertebrobasilar system was supplied by multiple collaterals from both posterior communicating arteries and right external carotid artery. We performed stent-angioplasty of bilateral internal cerebral arterial stenosis, and then acute infarction developed on bilateral superior cerebellar artery territories. The authors assumed that the infarction occurred due to hemodynamic change between internal carotid artery and external carotid artery after stent-angioplasty for stenosis of right internal carotid artery.

Comparison of Drug-eluting Coronary Stents, Bare Coronary Stents and Self-expanding Stents in Angioplasty of Middle Cerebral Artery Stenoses

OBJECTIVE: The purpose of this study is to investigate the results of treatment using stent-angioplasty for symptomatic middle cerebral arterial (MCA) stenosis and comparison of in-stent restenosis between drug-eluting stents (DES), bare metal coronary stents (BMS) and self-expanding stents (SES). MATERIALS AND METHODS: From Jan. 2007 to June. 2012, 34 patients (mean age +/- standard deviation: 62.9 +/- 13.6 years) with MCA stenosis were treated. Inclusion criteria were acute infarction or transient ischemic attacks (TIAs) and angiographically proven symptom related severe stenosis. Stents used for treatment were DES (n = 8), BMS (n = 13) and SES (n = 13). National Institutes of Health Stroke Scale (NIHSS) at admission was 2.5 +/- 3.1 and mean stenosis rate was 79.0 +/- 8.2%. Assessment of clinical and angiographic results was performed retrospectively. RESULTS: Among 34 patients, periprocedural complications occurred in four cases (11.8%), however, only two cases (6.0%) were symptomatic. All patients were followed clinically (mean follow-up period; 40.7 +/- 17.7 months) and 31 were followed angiographically (91.2%. 13.4 +/- 8.5 months). There was no occurrence of repeat stroke in all patients; however, mild TIAs related to restenosis occurred in three of 34 patients (8.8%). The mean NIHSS after stent-angioplasty was 1.7 +/- 2.9 and 0.8 +/- 1.1 at discharge. The modified Rankin score (mRS) at discharge was 0.5 +/- 0.9 and 0.3 +/- 0.8 at the last clinical follow-up. In-stent restenosis over 50% occurred in five of 31 angiographically followed cases (16.1%), however, all of these events occurred only in patients who were treated with BMS or SES. Restenosis rate was 0.0% in the DES group and 20.8% in the other group (p = 0.562); it did not differ between BMS and SES (2/11 18.2%, 3/13 23.1%, p = 1.000). CONCLUSION: Stent-angioplasty appears to be effective for symptomatic MCA stenosis. As for restenosis, in our study, DES was presumed to be more effective than BMS and SES; meanwhile, the results did not differ between the BMS and SES groups.

A Case of Meningeal Carcinomatosis from Prostate Cancer / 대한내과학회지

Meningeal carcinomatosis in patients with prostate cancer is very rare. Recently, we experienced a case of meningeal carcinomatosis in a patient with prostate cancer. He had undergone a radical prostatectomy 11 years before presentation and had undergone chemotherapy 4 years before presentation due to bone metastases. This time, he visited the emergency department because of a seizure. Although cerebrospinal fluid (CSF) examinations did not reveal malignant cells, we diagnosed meningeal carcinomatosis based on positive CSF prostate-specific antigen and magnetic resonance imaging (MRI) findings. The diagnosis was confirmed pathologically. We treated the patient with whole brain radiotherapy and intrathecal chemotherapy. We report a case of prostate cancer with meningeal carcinomatosis with a literature review.

Guidelines for the Management of Unruptured Intracranial Aneurysm / 대한뇌혈관외과학회지

Intracranial aneurysmal rupture causes subarachnoid hemorrhage which usually leads to fatality or severe disability. Treatment of unruptured intracranial aneurysms (UIAs) can substantially reduce the risk of rupture and prevent the grave consequences, but the risk of prophylactic treatment cannot be ignored. UIAs have diverse characteristics and management strategy needs to be tailored according to their location, size and clinical status. In the absence of level I evidence, the treatment guidance often relied on expert's opinions and experience. Knowledge of the natural course and management risks of individual aneurysms can help to guide treatment decision, but the natural history is still controversial and risks are not clearly defined. The Korean Society of Cerebrovascular Surgeons (KSCVS) decided to issue a Korean version of UIA management guideline as a framework for the treatment decision and as a basis for future studies, following 'Guideline Development Manual' of the Clinical Research Center for Stroke (CRCS). The organized committee systematically reviewed relevant literature and major guidelines published between January 2000 and July 2010 and took a developmental strategy of adaptation rather than de novo methods. On the basis of interpretation of the published evidences, recommendations were synthesized, and the level of evidence and the grade of recommendation were determined using the methods adapted from those of the US Agency for Healthcare Policy and Research and CRCS. The current guideline focuses on three domains of natural history, diagnosis and treatment of UIAs. The hierarchy of evidence and the recommendation grading indicate the current level by the literature and do not indicate the necessity or the prohibition of a certain clinical practice. Accordingly, this guideline cannot provide the answer for every clinical situation and should not take precedence over the clinical judgment of responsible physicians for individual patients. The final judgment regarding the care of a particular patient must be made by the physician and patient in light of circumstances specific to that patient. This is the first version of the UIA management guideline in Korea and new evidences will be timely and continuously updated in the future guidelines.

Troublesome Occipital Neuralgia Developed by C1-C2 Harms Construct

Recently, Harms and Melcher modified Goel's approach, the C1 lateral mass and C2 pedicle screw fixation, and the new technique is currently in favor among neurosurgeons. Comparing to the advantages of Harms construct, the disadvantages were not extensively investigated. We experienced a patient with severe occipital pain developed after the C1 lateral mass screw placement for the traumatic atlantoaxial instability. We reviewed literatures about Harms construct with focus on the occipital neuralgia as a postoperative complication and suggest here technical tips to avoid the troublesome pain.

Modified Trajectory of C2 Laminar Screw - Double Bicortical Purchase of the Inferiorly Crossing Screw

The crossing laminar screw fixation might be the most recently developed approach among various fixation techniques for C2. The new construct has stability comparable to transarticular or transpedicular screw fixation without risk of vertebral artery injury. Quantitative anatomical studies about C2 vertebra suggest significant variation in the thickness of C2 lamina as well as cross sectional area of junction of lamina and spinous process. We present an elderly patient who underwent an occipito-cervical stabilization incorporating crossed C2 laminar screw fixation. We preoperatively recognized that she had low profiles of C2 lamina, and thus made a modification of trajectory for the inferiorly crossing screw. We introduce a simple modification of crossing C2 laminar screw technique to improve stability in patients with low laminar profiles.

Computerized Tomographic Measurements of Morphometric Parameters of the C2 for the Feasibility of Laminar Screw Fixation in Korean Population

OBJECTIVE: C2 laminar screw fixation is considered as an excellent alternative to Magerl's transfacetal approach or Harms construct for the atlantoaxial stabilization. However, to our knowledge, there is no report on the feasibility of the new approach to Korean population. We investigated morphometric parameters of the dorsal arch of the C2 to provide the quantitative data for the feasibility of laminar screw fixation. METHODS: One-hundred-and-two patients' cervical computed tomography had been reconstructed and investigated on the anatomical parameters related with C2 laminar screw placement. Sixty patients were male and forty-two patients were female. Measurements included the laminar thickness and slope, spino-laminar angle, and maximal screw length. RESULTS: Ages ranged from 20 to 81 and the mean age was 48.4. Mean laminar thickness was 5.7 mm (+/-1.0) (5.8 mm in male and 5.4 mm in female). Fifty-one patients (50%) had a laminar thickness smaller than 5.5 mm at least unilaterally, therefore the patients were considered as inappropriate candidates for the laminar screw fixation in the smaller side of the laminae. Mean value of maximal length of screw was 33.3 mm (34.3 mm in male and 31.9 mm in female). Mean spino-laminar angle was 43.2degrees and mean slope angle was 32.9degrees. CONCLUSION: Half of patients had inappropriate laminar profiles to accommodate a 3.5 mm screw in at least one side of the axis. The three-dimensional computed tomography reconstruction is mandatory for the preoperative assessment for the feasibility of the C2 lamina.

Is Extravasation of Radiographic Contrast a Predictor of Hematoma Enlargement in Spontaneous Supratentorial Intracerebral Hemorrhage? / 대한뇌혈관외과학회지

BACKGROUND AND PURPOSE: The enlargement of a hematoma occurs commonly in patients with spontaneous intracerebral hemorrhage (ICH) after hospitalization and can worsen the clinical outcome. We conducted this study to determine whether extravasation of a radiographic contrast agent is a predictor of hematoma enlargement occurring after admission in patients with spontaneous ICH. METHODS: We reviewed the clinical records and computerized tomography (CT) scan findings of 384 patients with spontaneous ICH admitted within 24 hours of ictus from 2002 to 2005. Only 71 patients with primary ICH in the basal ganglia or thalamus were included in the study. The first CT scan was preformed within 24 hours of onset and the second CT scan was preformed within 72 hours of onset. We compared patients with and without hematoma enlargement according to the radiological findings, clinical characteristics and laboratory data. RESULTS: Seventeen patients (23.9%) showed hematoma enlargement after admission. Extravasation of the radiographic contrast agent on a CT scan was seen in 23 patients (32.4%). The presence of contrast extravasation on a CT scan closely correlated with evidence of hematoma enlargement, as seen on a follow-up CT scan (p = 0.000). Other variables did not reach statistical significance for the independent association with hematoma enlargement. CONCLUSIONS: Due to a high risk for hematoma enlargement, patients with spontaneous ICH in the basal ganglia and thalamus, especially those with evidence of contrast extravasation on a CT scan, should be closely observed. Short term followup radiological studies are needed for the verification of hematoma enlargement.

Recanalization Rate and its Associated Factors after Intravenous Tissue Plasminogen Activator Thrombolysis for Acute Major Cerebral Arterial Occlusion / 대한뇌혈관외과학회지

PURPOSE: To investigate the recanalization rate after intravenous administration of recombinant tissue plasminogen activator (IV-tPA) for acute major arterial occlusion of the anterior cerebral circulation and to investigate the relationship between atrial fibrillation and recanalization. METHODS: From April 2005 to April 2006, 16 patients with acute major arterial occlusion of the anterior cerebral circulation were treated with IV-tPA. Recanalization was classified as good (as compared with an unoccluded contralateral vessel; thrombolysis in myocardial infarction (TIMI) classification grade II and III) and poor (TIMI grade 0 and I). The clinical and radiological parameters associated with recanalization were analyzed. The clinical outcomes were evaluated by use of the National Institute of Health Stroke Scale (NIHSS) at 3 months after treatment. RESULTS: Of all of the 16 patients, 11 patients (68.8%) showed good recanalization. Among these 11 patients, nine patients survived (81.8%). However, only one patient survived (20%, p = 0.036) of the other five patients who showed poor recanalization. The pretreatment NIHSS score and atrial fibrillation were significantly correlated with the recanalization rate. Atrial fibrillation was found in 8 of 16 patients (50.0%) as the cause of the cerebral embolic infarction. Among the patients with atrial fibrillation only three patients showed good recanalization (37.5%); patients without atrial fibrillation showed good recanalization (100%, p = 0.026). CONCLUSIONS: I.-tPA appears to be effective and safe as a recanalization method for acute major cerebral arterial occlusion in patients that do not have atrial fibrillation. Good recanalization was associated with a good clinical result. Atrial fibrillation is a significant associated factor of poor recanalization and high mortality.

The Incidence of Aneurysmal Subarachnoid Hemorrhage in Youngdong District, Korea

OBJECTIVE: The purpose of this study is to investigate the incidence of aneurysmal subarachnoid hemorrhage (SAH) in Youngdong district for 10 years. METHODS: From Jan. 1997 to Dec. 2006, 732 patients (327 males, 405 females, mean age: 54.8+/-13.1 years) with spontaneous SAH were admitted to our hospital. We reviewed the medical records and radiological findings regarding to the ictus of SAH, location and size of the ruptured aneurysms, Hunt-Hess grade and Fisher grade on admission, personal details such as address, age, and sex, and previous history of medical diseases. RESULTS: In these 732 patients, 672 cases were confirmed as aneurysmal SAH. Among them, 611 patients (262 males, 349 females, mean age: 54.9+/-13.2 years) came from Youngdong district. The average crude annual incidence of aneurysmal SAH for men, women, and both sexes combined in Youngdong district was 7.8+/-1.7, 10.5+/-2.7, and 9.1+/-2.1 per 100,000 population, respectively. Because of the problems related to the observation period and geographical confinement, it was suspected that the representative incidence of aneurysmal SAH in Youngdong district should be made during the later eight years in six coastal regions. Therefore, the average age-adjusted annual incidence for men, women, and both sexes combined was 8.8+/-1.4, 11.2+/-1.3 and 10.0+/-1.0, respectively in the coastal regions of Youngdong district from 1999 to 2006. CONCLUSION: In overall, our results on the incidence of aneurysmal SAH was not very different from previous observations from other studies.

Lumbo-sacro-pelvic Fixation Using Iliac Screws for the Complex Lumbo-sacral Fractures

Fractures of lumbo-sacral junction involving bilateral sacral wings are rare. Posterior lumbo-sacral fixation does not always provide with sufficient stability in such cases. Various augmentation techniques including divergent sacral ala screws, S2 pedicle screws and Galveston rods have been reported to improve lumbo-sacral stabilization. Galveston technique using iliac bones would be the best surgical approach especially in patients with bilateral comminuted sacral fractures. However, original Galveston surgery is technically demanding and bending rods into the appropriate alignment is time consuming. We present a patient with unstable lumbo-sacral junction fractures and comminuted U-shaped sacral fractures treated by lumbo-sacro-pelvic fixation using iliac screws and discuss about the advantages of the iliac screws over the rod system of Galveston technique.

Usefulness of Drug-Eluting Stents in Angioplasty and Stenting of the Vertebral Artery Origin : Comparison with Bare Stents: Clinical Research / 대한뇌혈관외과학회지

OBJECT: In the treatment of coronary atherosclerosis, drug-eluting stents are effective in decreasing the rate of major adverse cardiac events and angiographic restenosis compared with bare metal stents. However, the benefits and safety of using these new devices in the cerebral vasculature have not been evaluated. To assess the effectiveness of drug-eluting stents in the cerebral vasculature, the authors analyzed clinical and angiographic results after percutaneous transluminal angioplasty and stenting in patients with vertebral artery origin stenosis. METHODS: Ninety-one patients with 99 vertebral origin stenoses treated with percutaneous endovascular balloon angioplasty and stent placement during a period of 5.1 years (September 1999-October 2004). Follow-up angiograms were obtained from 38 patients with 42 lesions (24 men, 14 women ; mean age, 61.9 yrs ; mean follow-up period, 9.1 months). We reviewed the clinical and radiological records of these patients. RESULTS: Bare stents were implanted in 30 lesions, while drug-eluting stents were implanted in 12 lesions, with a mean residual stenosis of 5.1 %. The overall rate of moderate-to-severe restenosis (> or =50%) was 31.0 % (13 of 42 cases). The restenosis rate in the bare stent group was 36.7 %, compared with 16.7 % in the drug-eluting stent group (p=0.282). Comparing the restenosis rate in stented lesions with reference diameters less than 3.5 mm (11 with bare stents, 12 with drug-eluting stents), the restenosis rates were 63.6 % in the bare stent-group and 16.7 % in the drug-eluting stent-group (p=0.029). CONCLUSION: Drug-eluting stents placed in vertebral artery origin stenosis have lower restenosis rate than bare stents, particularly in small-sized vessels.

Usefulness of Drug-Eluting Stents in Angioplasty and Stenting of the Vertebral Artery Origin : Comparison with Bare Stents: Clinical Research / 대한뇌혈관외과학회지

OBJECT: In the treatment of coronary atherosclerosis, drug-eluting stents are effective in decreasing the rate of major adverse cardiac events and angiographic restenosis compared with bare metal stents. However, the benefits and safety of using these new devices in the cerebral vasculature have not been evaluated. To assess the effectiveness of drug-eluting stents in the cerebral vasculature, the authors analyzed clinical and angiographic results after percutaneous transluminal angioplasty and stenting in patients with vertebral artery origin stenosis. METHODS: Ninety-one patients with 99 vertebral origin stenoses treated with percutaneous endovascular balloon angioplasty and stent placement during a period of 5.1 years (September 1999-October 2004). Follow-up angiograms were obtained from 38 patients with 42 lesions (24 men, 14 women ; mean age, 61.9 yrs ; mean follow-up period, 9.1 months). We reviewed the clinical and radiological records of these patients. RESULTS: Bare stents were implanted in 30 lesions, while drug-eluting stents were implanted in 12 lesions, with a mean residual stenosis of 5.1 %. The overall rate of moderate-to-severe restenosis (> or =50%) was 31.0 % (13 of 42 cases). The restenosis rate in the bare stent group was 36.7 %, compared with 16.7 % in the drug-eluting stent group (p=0.282). Comparing the restenosis rate in stented lesions with reference diameters less than 3.5 mm (11 with bare stents, 12 with drug-eluting stents), the restenosis rates were 63.6 % in the bare stent-group and 16.7 % in the drug-eluting stent-group (p=0.029). CONCLUSION: Drug-eluting stents placed in vertebral artery origin stenosis have lower restenosis rate than bare stents, particularly in small-sized vessels.

Unruptured Aneurysms-Endovascular Treatment / 대한뇌혈관외과학회지

The management of unruptured aneurysm is controversial, and two main discussion points are its natural history and the role of endovascular coiling in the repair of this aneurysms. We reviewed our results of treatments using coil embolization for the unruptured intracranial aneurysms. We treated 106 unruptured aneurysms by endovascular coiling for the last 6 years. while 45 unruptured aneurysms were treated by clipping during same period. Seventy-six (71.7%) unruptured aneurysms were distributed in anterior circulation and 30 (28.3%) was in posterior circulation. Aneaurysms of paraclinoid carotid artery and vertebrobasilar artery was the most frequent location of endovascular coiling of UIAs and anticipated surgical difficulty was the most common reason for choosing coiling. Sixty-three (59.4%) aneurysms were smaller than 10 mm in maximum aneurysm size, 30 (28.3%) aneurysms were 11-20 mm, and 13 (12.2%) were over 21 mm. Complete embolization was achieved in 61 (57.5%) aneurysms, neck remnants in 35 (33.0%) aneurysms, incomplete embolization in 7 (6.7%), and attempted and failed was in three (2.8%). There were 9 procedural complications, 6 thromboembolisms, 2 aneurysm perforations and 1 coil migration. Three patients with thromboembolic complication and a coil migration patient remained in permanent neurologic deficit (morbidity : 3.8%). However, three thromboembolic complications and two aneurysm perforation recovered clinically well. In our series, small aneurysms (<10 mm) were involved larger number of preventive interventions of UIAs than large or giant size aneurysms. Although, over all morbidity and mortality of coil embolization for unruptured aneurysms in our series were low, the indications of repairing for small size unruptured aneurysms need to investigated further.

The Effect of Recombinant Tissue Plasminogen Activator on the Intracerebral Hematomas in Experimental Cat Models

OBJECTIVE: Recent clinical studies have demonstrated that intracisternal administration of recombinant tissue plasminogen activator(rt-PA) can facilitate the normal clearing of blood from the subarachnoid space. Urokinase, a first generation fibrinolytic agent, has been used to liquify such clots with some success. Therefore, recombinant tissue plasminogen activator, a second generation fibrinolytic drug that may be safer and more effective, is studied to evaluate its dosage to lyse clots in vitro and reactivity in the brain parenchyme. METHODS: Intracerebral hematomas were created by stereotactically injecting 2ml of clotted autogenous blood into the brain parenchyme of total 28 anesthetized adult cats (weighting 3.8 to 4.1kg). The control animals (group A) received 1ml of normal saline injected into the clots and the experimental animals received each 0.1mg of rt-PA (group B), 0.5mg of rt-PA (group C) and 1mg of rt-PA (group D) at 6 hours after the clot injection. RESULTS: 1. The amount of remained clots after lysing the hematomas were as follows: 1.80+/-0.17ml in group A, 1.65+/-0.23ml in group B, 0.61+/-0.37ml in group C and 0.52+/-0.34 in group D. The result indicated that hematomas in rt-PA treated groups (C & D) were lysed better than the control group. 2. At least 0.5mg of rt-PA should be required for the lysis of 2ml of hematomas. 3. Light microscopic examination revealed no histological evidence of hemorrhage in tissue sections from each brain. CONCLUSION: Recombinant tissue plasminogen activator may be safely and effectively employed for the lysis of intracerebral hematomas in animal model.

Outcome of the Expansive Open-door Laminoplasty with Titanium Miniplate in Cervical Stenosis

OBJECTIVE: The purpose of this study is to introduce a simple yet effective technique to secure the posterior elements in the open position after expansive open-door laminoplasty and to evaluate factors contributing to surgical results after laminoplasty. METHODS: Twenty two myelopathic or radiculopathic patients with multilevel cervical canal stenosis or ossification of the posterior longitudinal ligament were treated with an expansive open-door laminoplasty. Thirteen patients were cervical spinal stenosis and the other 9 patients were diagnosed as the ossification of the posterior longitudinal ligament. The posterior elements were stabilized in the open position with titanium miniplates without spacers. Morphometric analysis was performed on preoperative and postoperative plain radiographs to obtain spinal canal dimensions and to monitor construct integrity. RESULTS: The mean preoperative sagittal canal diameter was 10.3+/-2.2mm. These dimensions increased to 17.4+/-2.8mm after surgery. Most patients improved from the myelopathy or the radiculopathy and the mean recovery rate was 52.4+/-17.1%. The titanium miniplate constructs did not fail during the follow-up period (mean, 38.5 months) and the decompression was maintained. Serious complications such as instability and kyphosis did not develop in any cases. There were no significant factors that predict surgical outcome. CONCLUSION: Expansive open-door laminoplasty using titanium miniplates can be easily performed and is effective technique for decompression and maintenance of the spinal canal diameter.

Temporal Course and Outcome of Seizure in Patients with Arteriovenous Malformations after Radiosurgery

OBJECTIVE: The purpose of this study is to assess the temporal course of seizure in patients with arteriovenous malformation(AVM) after radiosurgery. METHODS: This study included 48 patients with AVM who underwent LINAC radiosurgery. Seventeen patients(35%) presented with seizure before the diagnosis of AVM. Clinical symptoms, location and volume of AVM, and temporal course of seizure after radiosurgery were analyzed retrospectively. RESULTS: Among seventeen patients with seizure episode before radiosurgery, twelve(70.6%) improved progressively and one patient(5.9%) did not show change in seizure frequency during the follow up period. Transient increase of seizure frequency and subsequent improvement was observed in 4 patients(23.5%), and seizure was controlled in two of these patients during the follow-up. Cumulative seizure frequency of all patients increased transiently from six months to 18 months after radiosurgery, and then it began to decrease significantly. CONCLUSION: Radiosurgery is an effective treatment modality resulting not only in the obliteration of AVM but also improvement of epilepsy associated with AVM. However, in some patients, transient increase of seizure frequency was observed before subsequent improvement. It was around 18 months after radiosurgery that seizure frequency significantly decreased in the majority of the patients. These data suggest that there is a possibility of transient aggravation of epilepsy after radiosurgery even though epilepsy improved eventually in most of the patients.