Se-Hyuk Kim

Incidence and Risk Factors of Recurrence After Endovascular Treatment of Intracranial Vertebrobasilar Dissecting Aneurysms

Background and Purpose— The incidence and risk factors for recurrence after endovascular treatment of intracranial vertebrobasilar dissecting aneurysms (VBDAs) have not been studied. We aimed to evaluate the incidence and risk factors for recurrence after endovascular treatment of VBDAs. Methods— A total of 111 patients (mean age, 45±10 years) underwent endovascular treatment for 119 VBDAs (ruptured/unruptured=73:46). Incidence and risk factors for recurrence were retrospectively evaluated. Results— Sixty-two VBDAs were treated by a reconstructive technique by using 1 to 3 overlapping stents with or without coiling, and 57 VBDAs were treated by a deconstructive technique by using proximal occlusion or internal trapping at the dissected segment of the parent artery. Follow-up angiography was available for 97 VBDAs (81.5%) in 89 patients at 3 days to 48 months (median, 13 months) after treatment. There were 13 recurrences: 6 had rebleeding but 7 had no rebleeding. All 6 hemorrhagic recurrences had initially presented with a ruptured form. Ten recurrences were confirmed by angiography, but 3 recurrences with rebleeding did not receive follow-up angiography. The rate of post-treatment recurrence did not differ between reconstructive and deconstructive treatments. Involvement of the posterior inferior cerebellar artery origin (odds ratio=8.026; 95% confidence interval, 1.561 to 41.259; P=0.013) was the only independent risk factor for recurrence. Conclusions— There was a 13% recurrence after endovascular treatment of VBDAs. Posterior inferior cerebellar artery origin involvement was the only independent risk factor for recurrence after endovascular treatment of VBDAs.

Posttreatment High-Grade Glioma: Usefulness of Peak Height Position with Semiquantitative MR Perfusion Histogram Analysis in an Entire Contrast-enhanced Lesion for Predicting Volume Fraction of Recurrence

PURPOSE To determine whether semiquantitative histogram analysis of the normalized cerebral blood volume (CBV) for an entire contrast material-enhanced lesion could be used to predict the volume fraction of posttreatment high-grade glioma recurrence compared with posttreatment change. MATERIALS AND METHODS The institutional review board approved this retrospective study. Informed consent was obtained. Thirty-nine patients with pathologically proved predominant tumor recurrence (tumor recurrence group, tumor fraction > or =50% [n = 14]), mixed tumor and posttreatment change (mixed group, tumor fraction > or =20% and <50% [n = 10]), and predominant posttreatment change (treatment change group, tumor fraction <20% [n = 15]) were evaluated. Histogram parameters of normalized CBV-histogram width, peak height position (PHP), and maximum value (MV)-were measured in entire contrast-enhanced lesions and used as discriminative indexes. Ordered logistic regression was used to determine independent factors for predicting the diseases of posttreatment contrast-enhanced lesions. Leave-one-out cross-validation was used to determine diagnostic accuracy. RESULTS PHP was an independent predictive factor (P = .003) for differentiating contrast-enhanced lesions in patients with posttreatment gliomas. According to receiver operating characteristic curve analyses, PHP provided sensitivity of 90.2% and specificity of 91.1% for differentiating tumor recurrence from mixed and treatment change groups at an optimum threshold of 1.7 by using leave-one-out cross-validation. MV helped distinguish treatment change group from tumor recurrence and mixed groups at an optimum threshold of 2.6 (sensitivity, 96.5%; specificity, 93.1%). CONCLUSION PHP can be used to predict the volume fraction of posttreatment high-grade glioma recurrence.

Pathologic Diagnosis of Recurrent Glioblastoma: Morphologic, Immunohistochemical, and Molecular Analysis of 20 Paired Cases

To evaluate the prognostic value of the volume of residual viable tumor versus therapy-induced necrosis in resection material and the diagnostic value of ancillary tests in recurrent glioblastoma (GBM), we conducted a retrospective review of 20 patients whose initial and recurrent specimens were available. Recurrent GBMs were graded according to the extent of histopathologic parameters: recurrent tumor with high-grade, non–high-grade, and pure high-grade tumor components and therapy-related necrosis. We also examined MIB-1 labeling, isocitrate dehydrogenase 1R132H mutation, and epidermal growth factor receptor amplification in primary and recurrent GBMs. To evaluate patient outcomes according to clinical and pathologic parameters, a survival analysis was performed, and correlations between histopathologic parameters and each ancillary test were assessed. Among clinical parameters, age above 60 years was associated with decreased survival (P=0.022), but other clinical parameters showed no significant association with overall survival. Among the 3 histopathologic parameters, the extent of recurrent tumor, including high-grade and non–high-grade components, revealed a significant association with overall survival (P=0.042), but neither the extent of pure high-grade components nor therapy-related necrosis showed any prognostic value. MIB-1 labeling, isocitrate dehydrogenase 1R132H mutation, and epidermal growth factor receptor amplification were useful for the diagnosis of recurrent GBMs but showed no prognostic value. Our data suggest that histopathologic evaluation on the basis of tumor extent in resected recurrent GBM specimens may provide additional prognostic information on the survival of patients with recurrent GBM.

Endovascular treatment of bilateral intracranial vertebral artery dissecting aneurysms presenting with subarachnoid hemorrhage.

BACKGROUND: Optimal management of bilateral vertebral artery dissecting aneurysms (bi-VDAs) causing subarachnoid hemorrhage (SAH) remains unclear. OBJECTIVE: To investigate the treatment methods and outcomes of bi-VDA causing SAH. METHODS: Seven patients were treated endovascularly for bi-VDA causing SAH. Treatment methods and outcomes were evaluated retrospectively. RESULTS: Two patients were treated with 2 overlapping stents for both ruptured and unruptured VDAs, 2 with 2 overlapping stents and coiling for ruptured VDA and with conservative treatment for unruptured VDA, 1 with internal trapping (IT) for ruptured VDA and stent-assisted coiling for unruptured VDA, 1 with IT for ruptured VDA and 2 overlapping stents for unruptured VDA, and 1 with IT for ruptured VDA and a single stent for unruptured VDA. None had rebleeding during follow-up (range, 15-48 months). All patients had favorable outcomes (modified Rankin Scale score, 0-2). On follow-up angiography at 6 to 36 months, 9 treated and 2 untreated VDAs revealed stable or improved state, whereas 3 VDAs in 2 patients showed regrowth. Of the 3 recurring VDAs, 1 was initially treated with IT but recurred owing to retrograde flow to the ipsilateral posterior inferior cerebellar artery (PICA), the second was treated with single stent but enlarged, and the last was treated with 2 overlapping stents and coiling but recurred from the remnant sac harboring the PICA origin. All 3 recurred VDAs were retreated with coiling with or without stent insertion. CONCLUSION: Bilateral VDAs presenting with SAH were safely treated with endovascular methods. However, endovascular treatment may be limited for VDAs with PICA origin involvement.

Radiation-Induced Intratumoral Necrosis and Peritumoral Edema after Gamma Knife Radiosurgery for Intracranial Meningiomas

Objective To study the clinical significance and relevant factors of radiation-induced intratumoral necrosis (RIN) and peritumoral edema (PTE) after Gamma knife radiosurgery (GKRS) for intracranial meningiomas. Methods We retrospectively analyzed the data of 64 patients who underwent GKRS for intracranial meningioma. The mean lesion volume was 4.9 cc (range, 0.3-20), and the mean prescription dose of 13.4 Gy (range, 11-18) was delivered to the mean 49.9% (range, 45-50) isodose line. RIN was defined as newly developed or enlarged intratumoral necrosis after GKRS. Results RIN and new development or aggravation of PTE were observed in 21 (32.8%) and 18 (28.1%) cases of meningioma, respectively during the median follow-up duration of 19.9±1.0 months. Among various factors, maximum dose (>25 Gy) and target volume (>4.5 cc) were significantly related to RIN, and RIN and maximum dose (>24 Gy) were significantly related to the development or aggravation of PTE. In 21 meningiomas with development of RIN after GKRS, there was no significant change of the tumor volume itself between the times of GKRS and RIN. However, the PTE volume increased significantly compared to that at the time of GKRS (p=0.013). The median interval to RIN after GKRS was 6.5±0.4 months and the median interval to new or aggravated PTE was 7.0±0.7 months. Conclusion A close observation is required for meningiomas treated with a maximum dose >24 Gy and showing RIN after GKRS, since following or accompanying PTE may deteriorate neurological conditions especially when the location involves adjacent critical structures.

Therapeutic Effect of Gamma Knife Radiosurgery for Multiple Brain Metastases

OBJECTIVE The aim of this study is to evaluate the therapeutic effects of gamma knife radiosurgery (GKRS) in patients with multiple brain metastases and to investigate prognostic factors related to treatment outcome. METHODS We retrospectively reviewed clinico-radiological and dosimetric data of 36 patients with 4-14 brain metastases who underwent GKRS for 264 lesions between August 2008 and April 2011. The most common primary tumor site was the lung (n=22), followed by breast (n=7). At GKRS, the median Karnofsky performance scale score was 90 and the mean tumor volume was 1.2 cc (0.002-12.6). The mean prescription dose of 17.8 Gy was delivered to the mean 61.1% isodose line. Among 264 metastases, 175 lesions were assessed for treatment response by at least one imaging follow-up. RESULTS The overall median survival after GKRS was 9.1±1.7 months. Among various factors, primary tumor control was a significant prognostic factor (11.1±1.3 months vs. 3.3±2.4 months, p=0.031). The calculated local tumor control rate at 6 and 9 months after GKRS were 87.9% and 84.2%, respectively. Paddicks conformity index (>0.75) was significantly related to local tumor control. The actuarial peritumoral edema reduction rate was 22.4% at 6 months. CONCLUSION According to our results, GKRS can provide beneficial effect for the patients with multiple (4 or more) brain metastases, when systemic cancer is controlled. And, careful dosimetry is essential for local tumor control. Therefore, GKRS can be considered as one of the treatment modalities for multiple brain metastase.

A case of pigmentary orthochromatic leukodystrophy with findings of proton MR spectroscopy and serial brain MRIs

Despite a few case reports over the last 60 years, little progress has been made in defining the phenotype, genotype and pathophysiological mechanisms involved in pigmentary orthochromatic leukodystrophy (POLD). Furthermore, there is currently no data available regarding MRI in patients in the relatively early stages of POLD. Here, we present a 37 year old male patient with brain biopsy-proven POLD who had brain MRIs three times during the first year of his clinical course and proton MR spectroscopy (MRS) throughout his diagnostic evaluation. This patient with POLD was clinically characterized by seizures, rapidly progressive frontally predominant dementia and gait disturbance. The brain MRIs taken serially over the first year revealed progressive development of frontal-predominant white matter changes in the periventricular areas during the earlier periods, which later spread into the deep white matter. His MRS was helpful in the diagnostic approach because the results enabled demyelinating changes to be distinguished from other disease processes such as ischemia, gliosis or tumors. The MRS findings also reflected the disease dynamics because metabolic derangement was observed, even in the white matter that appeared normal. The findings presented here provide insight into the dynamics of POLD.

Gamma Knife radiosurgery for cystic brain metastases

Objective. The goal of this study was to investigate the treatment results of Gamma Knife radiosurgery (GKRS) for cystic brain metastases and relevant factors associated with local tumor control. Materials and methods. We retrospectively reviewed the clinical, radiological, and dosimetry data of 37 cystic brain metastases of 28 patients who were treated with GKRS. Cyst drainage was performed in 8 large lesions before GKRS to decrease the target volume. The mean target volume was 4.8 (range, 0.3–15.8) cc at the time of GKRS, and the mean prescription dose was 16.6 (range, 13–22) Gy. Results. The actuarial median survival time was 17.7 ± 10.2 months, and the primary tumor status was a significant prognostic factor for survival. The actuarial local tumor control rate at 6 and 12 months was 93.1 and 82.3%, respectively. Among the various factors, only prescription dose (>15 Gy) was a significant factor related to local tumor control after multivariate analysis (p = 0.049). Cyst volume or cyst/total tumor volume ratio did not influence local control after GKRS, when the target volume was reduced to about 15 cc after cyst drainage. Conclusion. According to our results, we suggest that stereotactic radiosurgery should be considered as one of the treatment options for cystic brain metastases, when large tumor volume can be reduced by surgical drainage before radiosurgery, especially for patients with a controlled primary tumor.

Risk Factors Predicting Unfavorable Neurological Outcome during the Early Period after Traumatic Brain Injury.

OBJECTIVE We aimed to identify clinico-radiological risk factors that may predict unfavorable neurological outcomes in traumatic brain injury (TBI), and to establish a guideline for patient selection in clinical trials that would improve neurological outcome during the early post TBI period. METHODS Initial clinico-radiological data of 115 TBI patients were collected prospectively. Regular neurological assessment after standard treatment divided the above patients into 2 groups after 6 months : the Favorable neurological outcome group (GOS : good & moderate disability, DRS : 0-6, LCFS : 8-10) and the Unfavorable group (GOS : severe disability-death, DRS : 7-29 and death, LCFS : 1-7 and death). RESULTS There was a higher incidence of age >/=35 years, low initial GCS score, at least unilateral pupil dilatation, and neurological deficit in the Unfavorable group. The presence of bilateral parenchymal lesions or lesions involving the midline structures in the initial brain CT was observed to be a radiological risk factor for unfavorable outcome. Multivariate analysis demonstrated that age and initial GCS score were independent risk factors. The majority of the Favorable group patients with at least one or more risk factors showed improvement of GCS scores within 2 months after TBI. CONCLUSION Patients with the above mentioned clinico-radiological risk factors who received standard treatment, but did not demonstrate neurological improvement within 2 months after TBI were deemed at risk for unfavorable outcome. These patients may be eligible candidates for clinical trials that would improve functional outcome after TBI.

Neurological Change after Gamma Knife Radiosurgery for Brain Metastases Involving the Motor Cortex.

Background Although Gamma Knife radiosurgery (GKRS) can provide beneficial therapeutic effects for patients with brain metastases, lesions involving the eloquent areas carry a higher risk of neurologic deterioration after treatment, compared to those located in the non-eloquent areas. We aimed to investigate neurological change of the patients with brain metastases involving the motor cortex (MC) and the relevant factors related to neurological deterioration after GKRS. Methods We retrospectively reviewed clinical, radiological and dosimetry data of 51 patients who underwent GKRS for 60 brain metastases involving the MC. Prior to GKRS, motor deficits existed in 26 patients (50.9%). The mean target volume was 3.2 cc (range 0.001–14.1) at the time of GKRS, and the mean prescription dose was 18.6 Gy (range 12–24 Gy). Results The actuarial median survival time from GKRS was 19.2±5.0 months. The calculated local tumor control rates at 6 and 12 months after GKRS were 89.7% and 77.4%, respectively. During the median clinical follow-up duration of 12.3±2.6 months (range 1–54 months), 18 patients (35.3%) experienced new or worsened neurologic deficits with a median onset time of 2.5±0.5 months (range 0.3–9.7 months) after GKRS. Among various factors, prescription dose (>20 Gy) was a significant factor for the new or worsened neurologic deficits in univariate (p=0.027) and multivariate (p=0.034) analysis. The managements of 18 patients were steroid medication (n=10), boost radiation therapy (n=5), and surgery (n=3), and neurological improvement was achieved in 9 (50.0%). Conclusion In our series, prescription dose (>20 Gy) was significantly related to neurological deterioration after GKRS for brain metastases involving the MC. Therefore, we suggest that careful dose adjustment would be required for lesions involving the MC to avoid neurological deterioration requiring additional treatment in the patients with limited life expectancy.