Jun Kyeung Ko

Hemorrhage Rates Associated with Two Methods of Ventriculostomy: External Ventricular Drainage vs. Ventriculoperitoneal Shunt Procedure

Cerebrospinal fluid (CSF) diversion is an essential component of neurosurgical care, but the rates and significance of hemorrhage associated with external ventricular drainage (EVD) and ventriculoperitoneal (VP) shunt procedures have not been well quantified. In this retrospective study, the authors examined the frequencies of hemorrhagic complications associated with EVD and VP shunt procedures, and attempted to identify associated risk factors. The treatment records of 370 EVDs in 276 patients and 102 VP shunts in 96 patients performed between 2008 and 2010 were retrospectively reviewed. Post-insertion computed tomographic (CT) scans were analyzed for any new hemorrhage related to the ventricular catheter. The effects of diagnosis at admission, endovascular treatment, anti-platelet medication, and a concurrent craniotomy operation were included in the analysis conducted to identify risk factors of ventricular catheter-related hemorrhage. Hemorrhage following EVD was detected on CT scans in 76 (20.5%) of the 370 cases. However, symptomatic hemorrhage occurred in only 5 cases (1.4% of all EVDs). VP shunt was associated with a higher incidence of ventricular catheter-related hemorrhage than EVD (hemorrhage rate: 43.1%) and the rate of detectable neurological change was 2.9%. Multivariate logistic-regression analysis of risk factors of EVD-related hemorrhage identified preoperative anti-platelet medication as the only significant factor (odds ratio, 3.583 [95% confidence interval, 1.353 to 9.486]; p = 0.010). Ventriculostomy-related hemorrhagic complications were more common than anticipated, especially for the VP shunt procedure. However, such hemorrhages are rarely large, rarely the cause of neurological deterioration, and rarely require surgical removal. Preoperative anti-platelet medication appears to affect EVD-related hemorrhage development.

Crossing Y-stent technique with dual open-cell stents for coiling of wide-necked bifurcation aneurysms

OBJECTIVE Double stenting in a Y-configuration is a promising therapeutic option for wide-necked cerebral aneurysms not amenable to reconstruction with a single stent. We retrospectively evaluated the efficacy and safety of the crossing Y-stent technique for coiling of wide-necked bifurcation aneurysms. METHODS By collecting clinical and radiological data we evaluated from January 2007 through December 2013, 20 wide-necked bifurcation aneurysms. RESULTS Twelve unruptured and eight ruptured aneurysms in 20 patients were treated with crossing Y-stent-assisted coiling. Aneurysm size and neck size ranged from 3.2 to 28.2mm (mean 7.5mm) and from 1.9 to 9.1mm (mean 4.5mm). A Y-configuration was established successfully in all 20 patients. All aneurysms were treated with a pair of Neuroform stents. The immediate angiographic results were total occlusion in 17 aneurysms, residual neck in two, and residual sac in one. Peri-operative morbidity was only 5%. Fifteen of 18 surviving patients underwent follow-up conventional angiography (mean, 10.9 months). The result showed stable occlusion in all 15 aneurysms and asymptomatic in-stent occlusion in one branch artery. At the end of the observation period (mean, 33.5 months), all 12 patients without subarachnoid hemorrhage had excellent clinical outcomes (mRS 0), except one (mRS 2). Of eight patients with subarachnoid hemorrhage, four remained symptom free (mRS 0), while the other four had were dependent or dead (mRS score, 3-6). CONCLUSION In this report on 20 patients, crossing Y-stent technique for coiling of wide-necked bifurcation aneurysms showed a good technical safety and favorable clinical and angiographic outcome.

Retained Microcatheter after Onyx Embolization of Intracranial Arteriovenous Malformation

Endovascular embolization is being increasingly used to treat intracranial arteriovenous malformations (AVMs). However, we experienced two patients with retained microcatheters after AVM embolization using Onyx.

Functional outcome after recanalization for acute pure M1 occlusion of the middle cerebral artery as assessed by collateral CTA flow

OBJECTIVE Collateral flow is important for ischemic brain tissue after an acute occlusion of the cerebral artery. The purpose of this study was to evaluate baseline collateral flow, on CT angiography (CTA), as a predictor of functional outcome in patients who had endovascular recanalization, after acute pure first segment (M1) occlusion of the middle cerebral artery (MCA). METHODS Thirty patients with acute pure M1 occlusion treated by endovascular recanalization, who were ineligible for intravenous thrombolysis or resistant to intravenous thrombolysis, were reviewed. The relationship between baseline collateral flow, on CTA, and functional outcome, was analyzed. In addition, other factors affecting clinical outcome were assessed. RESULTS The mean NIHSS score on admission was 16.87±4.86 (7-24). The mean time interval between onset of stroke symptoms and recanalization was 324.37±68.38 (210-463) min. Successful recanalization (TICI 2b-3) was achieved in 18 patients (60%). Twenty-seven of 30 patients improved their NIHSS score (mean 8.4); NIHSS score 8.9±5.4 (median 10, range 0-16) at seven days. Two patients had aggravated symptoms and one patient had no change on the NIHSS score. At 90 days after recanalization, a modified Rankin Scale (mRS) of ≤3 was achieved in 15 patients (50%) and a mRS of ≤2 was achieved in nine patients (30%). Symptomatic intra-cerebral hemorrhage occurred in two patients (6.7%). Multivariate regression analysis showed an initial NIHSS score (p=0.004), grade of baseline collateral flow on CTA (p=0.025), presence of diabetes mellitus (p=0.037), and TICI scale (p=0.049) were factors associated with an improved NIHSS. For the mRS at 90 days, only the grade of the baseline collateral flow on CTA was associated with a good functional outcome (p=0.013). CONCLUSIONS The results of this study suggest that the grade of baseline collateral flow, on CTA, is an independent predictor of functional outcome for endovascular recanalization of acute pure M1 occlusion of the middle cerebral artery.

Emergent Recanalization with Stenting for Acute Stroke due to Athero-Thrombotic Occlusion of the Cervical Internal Carotid Artery : A Single Center Experience

Objective The purpose of this study is to demonstrate the technical feasibility and clinical efficacy of emergent carotid angioplasty and stenting (CAS) for acute stroke due to athero-thrombotic occlusion of the cervical internal carotid artery (ICA). Methods Review of medical records identified 17 patients who underwent emergent CAS for treatment of athero-thrombotic occlusion of the cervical ICA with acute stroke between 2009 and 2013. Eleven patients (64.7%) presented with concomitant intracranial artery occlusion, which was treated primarily by mechanical thrombectomy after CAS. Results Successful revascularization of the cervical ICA with emergent CAS was achieved in all patients. After CAS, intracranial recanalization with Thrombolysis in Cerebral Infarction ≥2b flow was achieved in four of the 11 patients (36.4%). The overall recanalization rate (cervical ICA and intracranial artery) was 10 of 17 patients (58.8%). Symptomatic intracranial hemorrhage occurred in two patients (11.8%), resulting in death. Ten patients (58.8%) showed improvement (decrease in NIHSS score of ≥4 points) at seven days after recanalization. Nine patients (52.9%) showed a favorable outcome (mRS ≤2) at the last follow-up. A favorable outcome (mRS ≤2) was obtained in four of the six patients with isolated cervical ICA occlusion (4/6, 66.7%) and five of 11 patients with intracranial tandem occlusion (5/11, 45.5%). Conclusion Emergent CAS for acute stroke due to athero-thrombotic occusion of the cervical ICA showed a good technical feasibility and favorable clinical outcome.

Non-Dura Based Intaspinal Clear Cell Meningioma

A 34-year-old female patient was presented with leg and hip pain for 6 months as well as voiding difficulty for 1 year. Magnetic resonance imaging revealed a well-demarcated mass lesion at L2-3. The mass was hypo-intense on T1- and T2-weighted images with homogeneous gadolinium enhancement. Surgery was performed with the presumptive diagnosis of intradural extramedullary meningioma. Complete tumor removal was possible due to lack of dural adhesion of the tumor. Histologic diagnosis was clear cell meningioma, a rare and newly included World Health Organization classification of meningioma usually affecting younger patients. During postoperative 2 years, the patient has shown no evidence of recurrence. We report a rare case of cauda equina clear cell meningioma without any dural attachment.

External Carotid Artery Angioplasty and Stenting Followed by Superficial Temporal Artery to Middle Cerebral Artery Anastomosis

A 31-year-old man presented with right hemiparesis, and magnetic resonance imaging revealed a small infarct at left basal ganglia. Digital subtraction angiography showed left cervical internal carotid artery (ICA) occlusion and severe stenosis of the ipsilateral external carotid artery (ECA) with collateral cerebral circulation fed by ECAs. Based on the results of a functional evaluation of cerebral blood flow, we performed preventive ECA angioplasty and stenting for advanced ECA stenosis to ensure sufficient blood flow to the superficial temporal artery. Eight weeks later, superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis was performed. His postoperative course was uneventful and no additional transient ischemic attacks have occurred. To our knowledge, this is the first report of preventive angioplasty and stenting for advanced narrowing of an ECA before STA-MCA anastomosis for ipsilateral ICA occlusion.

Intramedullary spinal cord metastasis of choriocarcinoma.

The authors describe a case of choriocarcinoma that metastasized to the cerebral cortex, vertebral body, and intramedullary spinal cord. A 21-year-old woman presented with sudden headache, vomiting and a visual field defect. Brain computed tomography and magnetic resonance examinations revealed an intracranial hemorrhage in the left temporo-parietal lobe and two enhancing nodules in the left temporal and right frontal lobe. After several days, the size of the hemorrhage increased, and a new hemorrhage was identified in the right frontal lobe. The hematoma and enhancing mass in the left temporo-parietal lobe were surgically removed. Choriocarcinoma was diagnosed after histological examination. At 6 days after the operation, her consciousness had worsened and she was in a state of stupor. The size of the hematoma in the right frontal lobe was enlarged. We performed an emergency operation to remove the hematoma and enhancing mass. Her mental status recovered slowly. Two months thereafter, she complained of paraplegia with sensory loss below the nipples. Whole spine magnetic resonance imaging revealed a well-enhancing mass in the thoracic intramedullary spinal cord and L2 vertebral body. Despite chemotherapy and radiotherapy, the patient died 13 months after the diagnosis.

Endovascular treatment using graft-stent for pseudoaneurysm of the cavernous internal carotid artery.

A 57-year-old man presented with a 2-day history of left oculomotor palsy. Digital subtraction angiography revealed a pseudoaneurysm of the left cavernous internal carotid artery (ICA) measuring 37×32 mm. The pseudoaneurysm was treated with a balloon expandable graft-stent to occlude the aneurysmal neck and preserve the parent artery. A post-procedure angiogram confirmed normal patency of the ICA and complete sealing of the aneurysmal neck with no opacification of the sac. After the procedure, the oculomotor palsy improved gradually, and had completely resolved 3 months after the procedure. A graft-stent can be an effective treatment for a pseudoaneurysm of the cavernous ICA with preservation of the parent artery.

Endovascular treatment of acute intracranial vertebral artery dissection: long-term follow-up results of internal trapping and reconstructive treatment using coils and stents

Background Endovascular internal trapping is an effective procedure for the treatment of acute vertebral artery dissection (VAD). However, the outcomes of reconstructive treatment have not been well established. The aim of our study is to evaluate the long-term clinical and angiographic results of endovascular internal trapping or reconstructive treatment of acute VAD. Methods Between 2005 and 2013, 26 patients with acute VAD were managed with internal coil trapping (n=10), stent-assisted coiling (n=14), stent only (n=1), and proximal occlusion (n=1). Stent-assisted coiling included the modified stent-assisted semi-jailing technique (n=10), balloon-in-stent technique (n=2), and coiling followed by balloon mounted stent (n=2). Digital subtraction angiography (DSA) was performed in all patients except for three who died during the acute stage. Results Of 26 patients with VAD, 14 and 12 presented with hemorrhagic and non-hemorrhagic types, respectively. The dominancy of the relevant artery was defined as dominant (n=9), even (n=12), and non-dominant (n=5). Reconstructive treatment was performed in six patients with ruptured VADs which failed balloon test occlusion and nine with non-hemorrhagic VADs. Clinical outcomes were favorable in 22 (84.6%), severe disability occurred in one, and there were three deaths (11.5%). All patients except the three who died had angiographic follow-up at 6–32 months (mean 10.4 months). The angiographic results of nine cases of internal trapping and one of proximal occlusion all showed a stable occlusion state. Among the 15 cases of reconstructive treatment, follow-up DSAs were available for the 13 surviving patients, 10 of which demonstrated stable occlusion of aneurysmal dilation and patent parent artery. Conclusions This study suggests that internal trapping is a stable and effective treatment for acute VAD. Reconstructive treatment using stent and coils could also be a feasible alternative modality for hemorrhagic type VAD. However, serial DSA follow-up is essential.