Ho Jun Seol, Kyu-Chang Wang, Seung-Ki Kim, Yong-Seung Hwang, Ki Joong Kim and Byung-Kyu Cho
Patients with moyamoya disease complain of headache before surgery, after surgery, or in both periods. To clarify the pathophysiological features of these headaches which are one of the major symptoms in moyamoya disease after indirect bypass surgery, the authors reviewed data obtained in patients with moyamoya disease who underwent such surgery at their institute.
The authors surveyed 204 children with moyamoya disease younger than 17 years of age who underwent indirect bypass surgery consecutively between 1988 and 2000. If headache and associated symptoms disturbed their daily activity, required rest and/or medication, and occurred at least once a month, the headache was regarded as significant and the patient was included in the study. A postoperative headache was defined as the presence of significant headache 12 months after the operation or later. Preoperative headache was documented in 44 patients. Postoperative headache was observed in 63% (28 of 44) of the patients with preoperative headache and in 6.3% (10 of 160) of those without preoperative headache. Aggravation on postoperative magnetic resonance images or single-photon emission computerized tomography scans did not correlate with this symptom (p = 0.729 and 0.203, respectively). The clinical course had the following features: 1) a coexisting stage of headache and transient ischemic attack; 2) a second stage of headache only; and 3) a final stage of improvement or disappearance of headache.
The authors demonstrated that headaches can persist or develop after indirect bypass surgery despite successful prevention of cerebral ischemia. In addition to decreased cerebral blood flow, progressive recruitment and redistribution of blood flow should be considered as a cause of headaches in patients with moyamoya disease.
Seung-Ki Kim, Kyu-Chang Wang, Yong-Seung Hwang, Ki Joong Kim, Jong Hee Chae, In-One Kim and Byung-Kyu Cho
Ideal epilepsy surgery would eliminate seizures without causing any functional deficits. The aim of the present study was to assess seizure outcomes and complications after epilepsy surgery in children with intractable epilepsy.
Data obtained in 134 children (75 boys and 59 girls) age 17 years or younger who underwent epilepsy surgery at Seoul National University Children's Hospital between 1993 and 2005 were retrospectively reviewed. Epilepsy surgery included temporal resection (59 cases), extratemporal resection (56 cases), functional hemispherectomy (7 cases), callosotomy (9 cases), multiple subpial transection (1 case), and disconnection of a hamartoma (2 cases). The mean follow-up duration was 62.3 months (range 12–168 months).
The overall seizure-free rate was 69% (93 of 134 cases). The seizure-free rate was significantly higher in children who underwent temporal resection than in those in whom extratemporal resection was performed (88 vs 55%, p < 0.05). The most frequent causes of treatment failure were related to the absence of structural abnormality demonstrated on magnetic resonance imaging, development-associated disease, widespread disease documented by postoperative electroencephalography, and limited resection due to the presence of functional cortex. There were no postoperative deaths. Visual field defects were the most common complication after temporal resection (22% [13 of 59 cases]), whereas hemiparesis (mostly transient) was the most common morbidity after extratemporal resection (18% [10 of 56 cases]).
Epilepsy surgery is an effective and safe therapeutic modality in childhood. In children with extratemporal epilepsy, more careful interpretation of clinical and investigative data is needed to achieve favorable seizure outcome.
Jong-Hyuk Park, Yong-Sook Park, Jong-Sik Suk, Seung-Won Park, Sung-Nam Hwang, Taek-Kyun Nam, Young-Baeg Kim and Won-Bok Lee
Cerebrospinal fluid typically enters the subarachnoid space from the ventricles via the fourth ventricular foramina. However, there is clinical evidence that CSF also flows in the opposite direction. Ventricular reflux of CSF from a cistern is a well-known phenomenon in radioisotope studies in patients with normal-pressure hydrocephalus. Additionally, the presence of ventricular blood in acute subarachnoid hemorrhage is frequently observed. The goal of this investigation was to examine the potential CSF pathways from cisterns to ventricles. The authors examined pathways in rat models in which they occluded the fourth ventricular outlets and injected a tracer into the subarachnoid space.
The model for acute obstructive hydrocephalus was induced using N-butyl cyanoacrylate (NBCA) in 10 Sprague-Dawley rats. After 3 days, cationized ferritin was infused into the lumbar subarachnoid space to highlight retrograde CSF flow pathways. The animals were sacrificed at 48 hours, and the brains were prepared. The CSF flow pathway was traced by staining the ferritin with ferrocyanide.
Ferritin was observed in the third ventricle in 7 of 8 rats with hydrocephalus and in the temporal horn of the lateral ventricles in 4 of 8 rats with hydrocephalus. There was no definite staining in the aqueduct, which suggests that the ventricular reflux originated from routes other than through the fourth ventricular outlets.
The interfaces between the quadrigeminal cistern and third ventricle and those between the ambient cistern and lateral ventricle appear to be potential sites of CSF reflux from cisterns to ventricles in obstructive hydrocephalus.
Young-Hoon Kim, Young Jin Lee, Jung Ho Han, Soyeon Ahn, Jaebong Lee, Jae Hyoung Kim, Byung Se Choi, Jae Seung Bang, Chae-Yong Kim, Gyojun Hwang, O-Ki Kwon and Chang Wan Oh
The authors aimed to assess whether the prevalence of intracranial aneurysms in patients with intracranial meningiomas was higher than that in a healthy population.
The authors performed a hospital-based case-control study of 300 patients with newly diagnosed intracranial meningiomas and 900 age- and sex-matched controls without a history of brain tumors to evaluate any associations between intracranial aneurysms and intracranial meningiomas. Unconditional multivariate logistic regression models were used for case-control comparisons.
Intracranial aneurysms were identified in 23 patients (7.7%) and 24 controls (2.7%; p < 0.001). There was a significant association between intracranial aneurysms and intracranial meningiomas (OR 2.913, 95% CI 1.613–5.261) and hypertension (OR 1.905, 95% CI 1.053–3.446). In a subgroup analysis of the patients with newly diagnosed intracranial meningiomas, there was a significant association between intracranial aneurysms and hypertension (OR 2.876, 95% CI 1.125–7.352) and tumor volume (OR 1.012, 95% CI 1.001–1.024). These patients were also more likely than controls to have other intracranial vascular diseases (p < 0.001), such as isolated occlusion of the intracranial vessels, excluding intracranial aneurysms.
The prevalence of intracranial aneurysms was higher in patients with intracranial meningiomas. Hypertension and tumor volume appear to be associated with the formation of intracranial aneurysms in these patients.
Yun-Sik Dho, Young Jae Kim, Kwang Gi Kim, Sung Hwan Hwang, Kyung Hyun Kim, Jin Wook Kim, Yong Hwy Kim, Seung Hong Choi and Chul-Kee Park
The aim of this study was to analyze the positional effect of MRI on the accuracy of neuronavigational localization for posterior fossa (PF) lesions when the operation is performed with the patient in the prone position.
Ten patients with PF tumors requiring surgery in the prone position were prospectively enrolled in the study. All patients underwent preoperative navigational MRI in both the supine and prone positions in a single session. Using simultaneous intraoperative registration of the supine and prone navigational MR images, the authors investigated the images’ accuracy, spatial deformity, and source of errors for PF lesions. Accuracy was determined in terms of differences in the ability of the supine and prone MR images to localize 64 test points in the PF by using a neuronavigation system. Spatial deformities were analyzed and visualized by in-house–developed software with a 3D reconstruction function and spatial calculation of the MRI data. To identify the source of differences, the authors investigated the accuracy of fiducial point localization in the supine and prone MR images after taking the surface anatomy and age factors into consideration.
Neuronavigational localization performed using prone MRI was more accurate for PF lesions than routine supine MRI prior to prone position surgery. Prone MRI more accurately localized 93.8% of the tested PF areas than supine MRI. The spatial deformities in the neuronavigation system calculated using the supine MRI tended to move in the posterior-superior direction from the actual anatomical landmarks. The average distance of the spatial differences between the prone and supine MR images was 6.3 mm. The spatial difference had a tendency to increase close to the midline. An older age (> 60 years) and fiducial markers adjacent to the cervical muscles were considered to contribute significantly to the source of differences in the positional effect of neuronavigation (p < 0.001 and p = 0.01, respectively).
This study demonstrated the superior accuracy of neuronavigational localization with prone-position MRI during prone-position surgery for PF lesions. The authors recommend that the scan position of the neuronavigational MRI be matched with the surgical position for more precise localization.
Ji Hoon Phi, Byung-Kyu Cho, Kyu-Chang Wang, Ji Yeoun Lee, Yong Seung Hwang, Ki Joong Kim, Jong-Hee Chae, In-One Kim, Sung-Hye Park and Seung-Ki Kim
The long-term surgical outcome of pediatric patients with epilepsy accompanied by focal cortical dysplasia (FCD) is not clear. The authors report on the long-term surgical outcomes of children with FCD, based on longitudinal analyses.
The authors retrospectively analyzed the records of 41 children who underwent epilepsy surgery for pathologically proven FCD. Twenty of these patients were male and 21 were female. The median age at surgery was 9 years (range 1–17 years).
The actuarial seizure-free rates were 49, 44, and 33% in the 1st, 2nd, and 5th years after surgery, respectively. There was no seizure recurrence after 3 years. Three patients with initial failure of seizure control experienced late remission of seizures (the so-called running-down phenomenon). Eventually, 19 patients (46%) were seizure free at their last follow-up visit. Absence of a lesion on MR imaging and incomplete resection were significantly associated with seizure-control failure. Concordance of presurgical evaluation data was a marginally significant variable for seizure control in patients with lesional epilepsy. Three patients with seizure-control failure became seizure free as a result of the running-down phenomenon. The actuarial rate of antiepileptic drug discontinuation was 91% in the 5th year in the seizure-free patients.
The seizure-free rate after surgery in children with FCD was 49% in the 1st year; however, it declined thereafter. The running-down phenomenon could be an important mechanism of seizure alleviation for patients with FCD during long-term follow-up. Because a complete resection of FCD has a strong prognostic implication for seizure control, a better method to define the extent of FCD is required to assist with resection, especially in nonlesional epilepsy.