Endovascular Coiling for a Wide-neck Bifurcated Aneurysm with Anterograde Horizontal Stenting via Microcatheter Looping: A Technical Case Report

Technical advances with devices such as catheters, balloons, and stents have widened the indications for endovascular coiling for unfavorable aneurysms. The authors report two cases of coil embolization for a wide-neck bifurcated aneurysm with anterograde horizontal stenting via microcatheter looping. Two women, aged 56 and 38 years, respectively, had an undertall- and overwide-neck aneurysm with bifurcated branches at the basilar bifurcation and middle cerebral bifurcation, respectively. The delivery microcatheter was steamed so that it could be looped deliberately to the opposite vessel. The enterprise stent was first anchored to the vessel of the posterior cerebral artery on one side. The remaining portion was spanned into a looped microcatheter to the opposite branch while pushing the stent. The Neuroform Atlas stent was passed directly through the looped segment of the microcatheter at the M2 branch and spanned horizontally by unsheathing. Under horizontal stenting, complete coil embolization was achieved without immediate or delayed complications in both cases. This novel technique presents a viable option for stent-assisted coiling within an optimal anatomy.

Magnetic Resonance Imaging Patterns of Post-Operative Spinal Infection: Relationship between the Clinical Onset of Infection and the Infection Site

OBJECTIVE: To investigate the magnetic resonance imaging (MRI) findings and the patterns of postoperative spinal infection according to the passage of time. METHODS: Institutional review board approval was obtained, and informed consent was not obtained for the retrospective review of patients’ medical records. A total of 43 patients (27 men and 16 women; mean age, 64) diagnosed with postoperative spinal infection were included in this study. We retrospectively reviewed the MRI findings and the medical records and categorized the infection sites based on MRI, i.e., anterior, posterior, and both parts. The duration of the clinical onset from surgery was divided, i.e., acute (≤2 weeks), subacute (2–4 weeks), and late (>4 weeks). RESULTS: Postoperative spinal infection was involved in the posterior part in 31 (72%), anterior part in two (4.7%), and both parts in 10 patients (23.3%). Abscess or phlegmon in the back muscles and laminectomy site were the most common MRI findings. The number of patients with acute, subacute, and late clinical onset were 35, two, and six, respectively (mean, 33.4 days; range, 1–730 days). The mean duration of the clinical onset was 12 days in the posterior part, 15.2 days in both parts, and 456.5 days in the anterior part. CONCLUSION: Postoperative spinal infection usually occurred within four weeks in the posterior part and over time the infection was considered to spread into the anterior part. For the evaluation of postoperative spinal infection, the posterior surgical field was more important than the vertebral body or the disc space on MRI.

Single-Stage Operation for Giant Schwannoma at the Craniocervical Junction with Minimal Laminectomy: A Case Report and Literature Review

Here we report a single-stage operation we performed on a patient with a large schwannoma that extended from the lower clivus to the cervico-thoracic junction caudally. A number of authors have previously performed multilevel laminectomy to remove giant schwannomas that extend for considerable length. This technique has caused cervical instability such as kyphosis or gooseneck deformity on several occasions. We removed the tumor with a left lateral suboccipital craniectomy with laminectomy only at C1 and without any subsequent surgery-related neurologic deficits. However, this technique requires meticulous preoperative evaluation on existence of Cerebrospinal fluid (CSF) cleft between the tumor and spinal cord on magnetic resonance imaging, of tumor origin located at the upper cervical root, and of detachment of tumor from the origin site.

Surgical Treatment for Falcotentorial Meningiomas

Among intracranial meningiomas, falcotentorial meningiomas, occurring at the junction of the falx cerebri and tentorial dural folds, are extremely rare. Because of their deep location, they are surrounded by critical structures, and have been regarded as one of the most challenging lesions for surgical treatment. In this study, we describe our surgical strategy for falcotentorial meningiomas and provide a review of our experience.

Cryptococcal Brainstem Abscess Mimicking Brain Tumors in an Immunocompetent Patient

Usually fungal infections caused by opportunistic and pathogenic fungi had been an important cause of morbidity and mortality among immunocompromised patients. However clinical data and investigations for immunocompetent pathogenic fungal infections had been rare and neglected into clinical studies. Especially Cryptococcal brainstem abscess cases mimicking brain tumors were also much more rare. So we report this unusual case. This 47-year-old man presented with a history of progressively worsening headache and nausea for 1 month and several days of vomituritions before admission. Neurological and laboratory examinations performed demonstrated no abnormal findings. Previously he was healthy and did not have any significant medical illnesses. A CT and MRI scan revealed enhancing 1.8x1.7x2.0 cm mass lesion in the left pons having central necrosis and peripheral edema compressing the fourth ventricle. And also positron emission tomogram scan demonstrated a hot uptake of fluoro-deoxy-glucose on the brainstem lesion without any evidences of systemic metastasis. Gross total mass resection was achieved with lateral suboccipital approach with neuronavigation system. Postoperatively he recovered without any neurological deficits. Pathologic report confirmed Cryptococcus neoformans and he was successively treated with antifungal medications. This is a previously unreported rare case of brainstem Cryptococcal abscess mimicking brain tumors in immunocompetent host without having any apparent typical meningeal symptoms and signs with resultant good neurosurgical recovery.

The Use of Magnetic Resonance Imaging in Predicting the Clinical Outcome of Spinal Arteriovenous Fistula

PURPOSE: Magnetic resonance imaging (MRI) has been used to screen and follow-up spinal dural arteriovenous fistulae (SDAVF). The purpose of this study was to evaluate the association between MRI findings and neurologic function in SDAVF. This study also investigated clinical features and treatment results of SDAVF. MATERIALS AND METHODS: A total of 15 consecutive patients who underwent embolization or surgery for SDAVF were included. We treated seven (60%) patients with embolization and six (40%) with surgery. We analysed clinical features, MRI findings, treatment results, and neurologic function. Neurologic function was measured by the Aminoff-Logue disability scale (ALS). RESULTS: Patients with longer levels of intramedullary high signal intensity in preoperative T2-weighted images (T2WI) exhibited worse pre- and postoperative ALS scores (r=0.557, p=0.031; r=0.530, p=0.042, Pearson correlation). Preoperative ALS score was significantly correlated with postoperative ALS score (r=0.908, p=0.000, Pearson correlation). The number of levels showing intramedullary high signal intensity in T2WI decreased significantly postoperatively (5.2+/-3.1 vs. 1.0+/-1.4, p=0.001, Wilcoxon ranked test). CONCLUSION: The number of involved levels of high signal intensity in preoperative T2WI is useful for predicting pre- and postoperative neurologic function in SDAVF.

The Use of Magnetic Resonance Imaging in Predicting the Clinical Outcome of Spinal Arteriovenous Fistula

PURPOSE: Magnetic resonance imaging (MRI) has been used to screen and follow-up spinal dural arteriovenous fistulae (SDAVF). The purpose of this study was to evaluate the association between MRI findings and neurologic function in SDAVF. This study also investigated clinical features and treatment results of SDAVF. MATERIALS AND METHODS: A total of 15 consecutive patients who underwent embolization or surgery for SDAVF were included. We treated seven (60%) patients with embolization and six (40%) with surgery. We analysed clinical features, MRI findings, treatment results, and neurologic function. Neurologic function was measured by the Aminoff-Logue disability scale (ALS). RESULTS: Patients with longer levels of intramedullary high signal intensity in preoperative T2-weighted images (T2WI) exhibited worse pre- and postoperative ALS scores (r=0.557, p=0.031; r=0.530, p=0.042, Pearson correlation). Preoperative ALS score was significantly correlated with postoperative ALS score (r=0.908, p=0.000, Pearson correlation). The number of levels showing intramedullary high signal intensity in T2WI decreased significantly postoperatively (5.2+/-3.1 vs. 1.0+/-1.4, p=0.001, Wilcoxon ranked test). CONCLUSION: The number of involved levels of high signal intensity in preoperative T2WI is useful for predicting pre- and postoperative neurologic function in SDAVF.

Characteristics and Management of Residual or Slowly Recurred Intracranial Aneurysms

OBJECTIVE: Residual aneurysm from incomplete clipping or slowly recurrent aneurysm is associated with high risk of subarachnoid hemorrhage. We describe complete treatment of the lesions by surgical clipping or endovascular treatment. METHODS: We analyzed 11 patients of residual or recurrent aneurysms who had undergone surgical clipping from 1998 to 2009. Among them, 5 cases were initially clipped at our hospital. The others were referred from other hospitals after clipping. The radiologic and medical records were retrospectively analyzed. RESULTS: All patients presented with subarachnoid hemorrhage at first time, and the most frequent location of the ruptured residual or recurrent aneurysm was in the anterior communicating artery to posterior-superior direction. Distal anterior cerebral artery, posterior communicating artery, and middle cerebral artery was followed. Repositioning of clipping in eleven cases, and one endovascular treatment were performed. No residual aneurysm was found in postoperative angiography, and no complication was noted in related to the operations. CONCLUSION: These results indicate the importance of postoperative or follow up angiography and that reoperation of residual or slowly recurrent aneurysm should be tried if such lesions being found. Precise evaluation and appropriate planning including endovascular treatment should be performed for complete obliteration of the residual or recurrent aneurysm.

Clinical Features and Surgical Results of ICA Bifurcation Aneurysms

OBJECTIVE: The aneurysms developed at internal carotid artery(ICA) bifurcation can be different from other aneurysms because there are many perforating arteries and the hemodynamic changes are characteristic. In this report, we present our cases of ICA bifurcation aneurysms and discuss the clinical features and surgical outcomes of these aneurysms. METHODS: From January 1989 to May 2001, total 808 patients(982 aneurysms) were operated for intracranial aneurysms at our hospital. Among them, twenty two patients(2.7%) had aneurysms at ICA bifurcation. We discussed clinical features according to mental status at admission, size, direction and multiplicity of aneurysms, presence of intracranial hemorrhage and rupture of ICA bifurcation aneurysms. And we also discussed the surgical results of operations depending on pre-operative Hunt-Hess grade and size of aneurysms. RESULTS: Mean age was 43.4 years old and 10 cases(45.5%) were below 40 years old. Six patients(27.2%) had large or giant aneurysms. Fifteen(68.2%) out of 22 patients had good results, 1 fair, 1 poor and 5 dead. CONCLUSION: In our ICA bifurcation aneurysm cases, we conclude that their onset is relative in younger age, and they has a higher incidence of multiple(34.6%) and larger aneurysm(27.2%) than other anterior circulatory aneurysm. And the surgical results of ICA bifurcation aneurysm are relatively poor.

Clinical Characteristics of Takayasu's Arteritis

BACKGROUND AND OBJECTIVES: akayasu's arteritis is a disease of unknown etiology which has recently been reported to be a systemic disease. This is a prospective study of the clinical features and angiographic findings of Takayasu's arteritis from a single center. SUBJECTS AND METHODS: orty five patients were diagnosed as Takayasu's arteritis according to the Numano's diagnostic criteria, where patients satisfying at least one criterion from elevated ESR or CRP, arterial wall enhancement at MRA or CT angiography, or carotid tenderness are categorized into the active group. A disease duration of one year was used to define the division of the disease into either acute or chronic. Ueno's and Numano's classifications obtained through various imaging studies, were used. RESULTS: t the time of diagnosis, 60% of patients were in the active stage while 40% were in inactive stage. Levels of ESR, CRP and fibrinogen were found to differ significantly according to disease activity. The most common type of Takayasu's arteritis was type III according to the Ueno's classification, and type V according to the Numano's. The left subclavian artery was involved most frequently (78.5%). The most commonly involved segment of the aorta was the abdominal aorta (64.4%). Mean systolic blood pressure of the right arm in the renal artery stenosis group was 156+/-39 mmHg, which was significantly higher than that in the group without renal artery stenosis (113+/-46 mmHg) (p=0.005). ESR and CRP were correlated with aortic signal intensity on contrast-enhanced MR imaging (ESR;r=0.685, p=0.007/CRP;r=0.596, p=0.041). CONCLUSION: akayasu's arteritis is a disease of unknown causes, especially among young female patients, and exhibits nonspecific and various symptoms. ESR and CRP remain as valuable indicators of disease activity. The MR enhancement intensity of the arterial wall shows a positive correlation with both ESR and CRP level and it therefore may be correlated to disease activity and represent a useful diagnostic indicator.

Assessment of Flow Dynamics of Cerebrospinal Fluid with Phase-contrast Cine MR Image

Phase contrast magnetic resonance imaging techniques can be used to evaluate the to-and-fro motion of cerebrospinal fluid(CSF) throughout CSF pathways between the ventricles and subarachnoid space of the brain and spine. This CSF motion is due to transmitted cardiac pulsation from systolic expansion of the cerebral hemispheres. To cover the entire cardiac cycle, peripheral cardiac triggering was used. Using this technique, we analyzed quantitative CSF motion over a cardiac cycle to distinguish normal CSF flow from that seen in hydrocephalus. We tested the reproducibility of the aqueductal CSF signal intensity on a phase contrast cine MR sequence in 28 patients with normal ventricle. Sixteen patients with obstructive hydrocephalus and 11 patients with normal pressure hydrocephalus(NPH) were investigated with the sequence before and after CSF diversion. The peak CSF flow velocity in aqueduct was significantly increased in patients with NPH and significantly decreased in patients with obstructive hydrocephalus(NPH group: 6.71cm/sec, control group: 2.94cm/sec, obstructive group; less than 1.0cm/sec). After LP shunting in NPH group, retrograde flow signal curves were anterogradely converted and the peak flow velocities were somewhat decreased(mean: 5.10cm/sec). The clinical diagnosis of NPH was well correlated with the results of cine MRI. After endoscopic third ventriculostomy in obstructive group, we could note increased CSF flow velocity both at prepontine cistern and precordal subarachnoid space with markedly increased flow at prepontine cistern. Phase contrast cine MRI is useful in evaluatng the CSF dynamics in patients with hyperdynamic aqueductal CSF (NPH) or aqueductal obstruction(obstructive hydrocephalus).

Clinical Analysis of Supratentorial Primitive Neuroectodermal Tumor

Fifteen patients with primitive neuroectodermal tumors were reviewed. Because of ongoing nosological difficulty, we include in this series only those tumors which are located in the cerebral hemisphere, and are composed of predominantly undifferentiated neuroepithelial tumor with or without glial or neuronal differentiation. The 20 months cumulative survival rate by Kaplan-Meir method was 40% and only two patients had a long term survival more than 5 years in this series. The prognosis of the patients with cerebral PNETs remains poor despite of treatment including surgical resection. Radiation therapy and/or chemotherapy. The histological features and the extent of surgical resection did not influence the patient's survival. But visible total resection afforded better control of local disease of the primary site.