Chang Taek Moon

Endovascular coil embolization of very small intracranial aneurysms.

IntroductionEndovascular coil embolization of very small (maximum dome diameter ≤3xa0mm) aneurysms is controversial because of a high risk for procedural rupture and technical difficulty. We report clinical and angiographic results of coil embolization of these aneurysms.MethodsFrom August 2005 through July 2009, 43 very small aneurysms (23 ruptured, 20 unruptured) in 38 patients (12 males, 26 females; mean age, 53xa0years) were embolized with detachable coils. Of those 38 patients, 24 (63%) presented with subarachnoid hemorrhage (SAH) from a very small aneurysm (nu2009=u200923) or another aneurysm (nu2009=u20091). We assessed initial angiographic results, procedural complications, and clinical condition with initial Hunt and Hess grade (HH) and Glasgow outcome scale (GOS) at discharge. Follow-up results were evaluated with conventional angiography and/or magnetic resonance angiography (MRA).ResultsInitial aneurysmal occlusion was total in 16 (37%), subtotal in 22 (51%), and partial in five (12%) aneurysms. There were five incidents of thrombosis (12%) and one procedural rupture (2%), but there was no definite adverse effect on clinical outcome. Of 24 patients with SAH, ten patients (42%) were in poor condition (HH 3 or 4) at admission. Seventeen of 24 patients (71%) had good or excellent outcome (GOS ≥4) at discharge. A 6-month or more follow-up angiography and/or MRA was available in 33 (11 total and 20 subtotal and 2 partial in initial occlusion) aneurysms (77%) in 28 patients and revealed stable occlusion in 20 aneurysms (61%), progressive total occlusion in 10 (30%), minor recanalization in 2 (6%), and major recanalization in 1 (3%).ConclusionsCoil embolization of very small aneurysms may be technically feasible with favorable clinical/angiographic outcomes and relatively low recanalization rate during 6xa0months or more follow-up period.

Traumatic Entrapment of the Vertebrobasilar Junction Due to a Longitudinal Clival Fracture: A Case Report

Vertebrobasilar junction entrapment due to a clivus fracture is a rare clinical observation. The present case report describes a 54-yr-old man who sustained a major craniofacial injury. The patient displayed a stuporous mental state (Glasgow Coma Scale [GCS]=8) and left hemiparesis (Grade 3). The initial computed tomography (CT) scan revealed a right subdural hemorrhage in the frontotemporal region, with a midline shift and longitudinal clival fracture. A decompressive craniectomy with removal of the hematoma was performed. Two days after surgery, a follow-up CT scan showed cerebellar and brain stem infarction, and a CT angiogram revealed occlusion of the left vertebral artery and entrapment of vertebrobasilar junction by the clival fracture. A decompressive suboccipital craniectomy was performed and the patient gradually recovered. This appears to be a rare case of traumatic vertebrobasilar junction entrapment due to a longitudinal clival fracture, including a cerebellar infarction caused by a left vertebral artery occlusion. A literature review is provided.

Serial Expression of Hypoxia Inducible Factor-1α and Neuronal Apoptosis in Hippocampus of Rats with Chronic Ischemic Brain

OBJECTIVEnThe purpose of this study is to investigate serial changes of hypoxia-inducible factor 1α (HIF-1α), as a key regulator of hypoxic ischemia, and apoptosis of hippocampus induced by bilateral carotid arteries occlusion (BCAO) in rats.nnnMETHODSnAdult male Wistar rats were subjected to the permanent BCAO. The time points studied were 1, 2, 4, 8, and 12 weeks after occlusions, with n=6 animals subjected to BCAO, and n=2 to sham operation at each time point, and brains were fixed by intracardiac perfusion fixation with 4% neutral-buffered praraformaldehyde for brain section preparation. Immunohistochemistry (IHC), western blot and terminal uridine deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were performed to evaluate HIF-1α expression and apoptosis.nnnRESULTSnIn IHC and western blot, HIF-1α levels were found to reach the peak at the 2nd week in the hippocampus, while apoptotic neurons, in TUNEL assay, were maximal at the 4th week in the hippocampus, especially in the cornu ammonis 1 (CA1) region. HIF-1α levels and apoptosis were found to fluctuate during the time course.nnnCONCLUSIONnThis study showed that BCAO induces acute ischemic responses for about 4 weeks then chronic ischemia in the hippocampus. These in vivo data are the first to show the temporal sequence of apoptosis and HIF-1α expression.

Clinical characteristics of cerebral venous thrombosis in a single center in Korea.

Objective The purpose of this study is to investigate the clinical characteristics of cerebral venous thrombosis (CVT) in a single center in Korea. Methods A total of 36 patients were diagnosed with CVT from August 2005 to May 2013. The patient data regarding age, sex, disease stage, pathogenesis, location, laboratory findings, radiological findings, and treatment modalities were retrospectively collected. The results were compared with those of previous studies in other countries. Results The patient group comprised 21 men and 15 women with a mean age of 46.9 years (ranging from three months to 77 years). The most common cause was a prothrombotic condition (8 patients, 22.2%). Within the patient group, 13 patients (36.1%) had a hemorrhagic infarction, whereas 23 (63.9%) had a venous infarction without hemorrhage. By location, the incidence of hemorrhagic infarction was the highest in the group with a transverse and/or sigmoid sinus thrombosis (n=9); however, the proportion of hemorrhagic infarction was higher in the cortical venous thrombosis group (75%) and the deep venous thrombosis group (100%). By pathogenesis, the incidence of hemorrhagic infarction was the highest in the prothrombotic group (n=6), which was statistically significant (p=0.016). Conclusion According to this study, CVT was more prevalent in men, and the peak age group comprised patients in the sixth decade. The most common cause was a prothrombotic condition. This finding was comparable with reports from Europe or America, in which CVT was more common in younger women. Hemorrhagic infarction was more common in the prothrombotic group (p=0.016) than in the non-prothrombotic group in this study.

Grading of intracerebral hemorrhage in ruptured middle cerebral artery aneurysms.

Objective To propose grading of intracerebral hemorrhage (ICH) in ruptured middle cerebral artery (MCA) aneurysms, which helps to predict the prognosis more accurately. Methods From August 2005 to December 2010, 27 cases of emergent hematoma evacuation and aneurysm clipping for MCA aneurysms were done in the authors clinic. Three variables were considered in grading the ICH, which were 1) hematoma volume, 2) diffuse subarachnoid hemorrhage (SAH) that extends to the contralateral sylvian cistern, and 3) the presence of midline shifting from computed tomography findings. For hematoma volume of greater than 25 mL, we assigned 2 points whereas 1 point for less than 25 cc. We also assigned 1 point for the presence of diffuse SAH whereas 0 point for the absence of it. Then, 1 point was assigned for midline shifting of greater than 5 mm whereas 0 point for less than 5 mm. Results According to the grading system, the numbers of patients from grade 1 to 4 were 4, 6, 8 and 9 respectively and 5, 7, 8, 4 and 3 patients belonged to Glasgow Outcome Scale (GOS) 5 to 1 respectively. It was found that the patients with higher GOS had lower ICH grade which were confirmed to be statistically significant (p<0.01). Preoperative Hunt and Hess grade and absence of midline shifting were the factors to predict favorable outcome. Conclusion The ICH grading system composed of above three variables was helpful in predicting the patients outcome more accurately.

Clinical Utility of an Automated Pupillometer in Patients with Acute Brain Lesion

Objective The purpose of this study was to evaluate the clinical utility and validity of using a pupillometer to assess patients with acute brain lesions. Methods Pupillary examinations using an automated pupillometer (NeurOptics®NPi™-100 Pupillometer) were performed every 4 hours and were simultaneously assessed using the Glasgow Coma Scale (GCS) and for intracranial pressure (ICP), from admission to discharge or expire in neuro-intensive care unit (NICU). Manual pupillary examinations were also recorded for comparison. By comparing these data, we evaluated the validity of using automated pupillometers to predict clinical outcomes. Results The mean values of the Neurologic Pupillary index (NPi) were different in the groups examined manually. The GCS correlated well with NPi values, especially in severe brain injury patients (GCS below 9). However, the NPi values were weakly correlated with intracranial pressure (ICP) when the ICP was lower than 30 cm H2O. The NPi value was not affected by age or intensity of illumination. In patients with a poor prognosis who had a Glasgow Outcome Scale (GOS) of 1 or 2, the mean initial NPi score was 0.88±1.68, whereas the value was 3.89±0.97 in patients with a favorable prognosis who had a GOS greater than 2 (p<0.001). For predicting clinical outcomes, the initial NPi value of 3.4 had the highest sensitivity and specificity. Conclusion An automated pupillometer can serve as a simple and useful tool for the accurate measurement of pupillary reactivity in patients with acute brain lesions.

Tiny aneurysms treated with single coil: Morphological comparison between bare platinum coil and matrix coil

OBJECTIVEnWe analyzed the angiographic results of tiny aneurysms treated with various kinds of single coils including polyglycolic-polylactic acid (PGLA)-coated coils.nnnMETHODSnForty aneurysms with diameters measuring less than 4mm were treated with a single bare platinum, Matrix1, or Matrix2 coil. Most of the aneurysms were treated with a 2 mm diameter coil, except for seven treated with a 3 mm coil, four treated with a 2.5 mm coil, and two treated with a 1.5 mm coil. The mean length of the coils was 3.6 cm.nnnRESULTSnWith mean packing ratios of 21.2%, 19.7%, and 22.8%, we achieved initial complete occlusion rates of 9.5% with the platinum coil, 28.6% with the Matrix1 coil, and 25.0% with the Matrix2 coil. The mean follow-up interval was 23.1 months and the complete occlusion rate improved up to 47.6% for the platinum coil, 57.1% for the Matrix1 coil, and 83.3%for the Matrix2 coil. Compared to the Platinum group, the Matrix2 group showed a greater tendency toward more complete occlusion on the follow-up images. Regardless of coil type, the aneurysms treated with a stent-assisted technique showed better complete occlusion rates (50.0% vs. 90.0%, p=0.03).nnnCONCLUSIONSnThe tiny aneurysms treated with a single Matrix2 coil tended to have better follow-up angiographic results than the aneurysms treated with a single platinum coil. Furthermore, the use of a stent-assisted technique and increasing the packing density also positively affected the healing of these tiny aneurysms.

Simple Coiling versus Stent-Assisted Coiling of Paraclinoid Aneurysms : Radiological Outcome in a Single Center Study

Objective Paraclinoid aneurysms are a group of aneurysms arising at the distal internal carotid artery. Due to a high incidence of small, wide-necked aneurysms in this zone, it is often challenging to achieve complete occlusion when solely using detachable coils, thus stent placement is often required. In the present study, we aimed to investigate the effect of stent placement in endovascular treatment of paraclinoid aneurysms. Methods Data of 98 paraclinoid aneurysms treated by endovascular approach in our center from August 2005 to June 2016 were retrospectively reviewed. They were divided into two groups: simple coiling and stent-assisted coiling. Differences in the recurrence and progressive occlusion between the two groups were mainly analyzed. The recurrence was defined as more than one grade worsening according to Raymond-Roy Classification or major recanalization that is large enough to permit retreatment in the follow-up study compared to the immediate post-operative results. Results Complete occlusion was achieved immediately after endovascular treatment in eight out of 37 patients (21.6%) in the stent-assisted group and 18 out of 61 (29.5%) in the simple coiling group. In the follow-up imaging studies, the recurrence rate was lower in the stent-assisted group (one out of 37, 2.7%) compared to the simple coiling group (13 out of 61, 21.3%) (p=0.011). Multivariate logistic regression model showed lower recurrence rate in the stent-assisted group than the simple coiling group (odds ratio [OR] 0.051, 95% confidence interval [CI] 0.005–0.527). Furthermore there was also a significant difference in the rate of progressive occlusion between the stent-assisted group (16 out of 29 patients, 55.2%) and the simple coiling group (10 out of 43 patients, 23.3%) (p=0.006). The stent-assisted group also exhibited a higher rate of progressive occlusion than the simple coiling group in the multivariate logistic regression model (OR 3.208, 95% CI 1.106–9.302). Conclusion Use of stents results in good prognosis not only by reducing the recurrence rate but also by increasing the rate of progressive occlusion in wide-necked paraclinoid aneurysms. Stent-assisted coil embolization can be an important treatment strategy for paraclinoid aneurysms when considering the superiority of long term outcome.

Relationship between Gyrus Rectus Resection and Cognitive Impairment after Surgery for Ruptured Anterior Communicating Artery Aneurysms.

Objective The gyrus rectus (GR) is known as a non-functional gyrus; hence, its resection is agreed to be a safe procedure frequently practiced to achieve a better surgical view during specific surgeries. This study aimed at comparing the cognitive outcomes following GR resection in patients who underwent surgery for ruptured anterior communicating artery (ACoA) aneurysms. Materials and Methods From 2012 to 2015, 39 patients underwent surgical clipping for ruptured ACoA aneurysms. Mini-mental state examinations (MMSE) were performed in 2 different periods. The statistical relationship between GR resection and MMSE results was evaluated, and further analysis of MMSE subgroup was performed. Results Twenty-five out of the 39 patients (64.19%) underwent GR resection. Mean initial and final MMSE scores in the GR resection group were 16.3 ± 9.8 and 20.8 ± 7.3, respectively. In the non-resection group, the mean initial and final MMSE scores were 17.1 ± 8.6 and 21.9 ± 4.5, respectively. Neither groups scores showed a significant change. Subgroup analysis of initial MMSE showed a significant difference in memory recall and language (p = 0.02) but not in the final MMSE scores. Conclusion There was no significant relationship between the GR resection and cognitive outcomes in terms of total MMSE scores after surgery for ruptured ACoA aneurysm. However, subgroup analysis revealed a temporary negative effect of GR resection in the categories of language and memory recall. This study suggests that GR resection should be executed superficially, owing to its close anatomical relationship with the limbic system.

Serial Mini-Mental Status Examination to Evaluate Cognitive Outcome in Patients with Traumatic Brain Injury

Objective This study was aimed at finding out the changes in cognitive dysfunction in patients with traumatic brain injury (TBI) and investigating the factors limiting their cognitive improvement. Methods Between January 2010 and March 2014, 33 patients with TBI participated in serial mini-mental status examination (MMSE). Their cognitive functions were statistically analyzed to clarify their relationship with different TBI status. Patients who developed hydrocephalus were separately analyzed in regards to their cognitive function depending on the placement of ventriculoperitoneal shunt (VPS). Results Bi-frontal lobe injury (β=-10.441, p<0.001), contre-coup injury (β=-6.592, p=0.007), severe parenchymal injury (β=-7.210, p=0.012), temporal lobe injury (β=-5.524, p=0.027), and dominant hemisphere injury (β=-5.388, p=0.037) significantly lowered the final MMSE scores. The risk of down-grade in the prognosis was higher in severe parenchymal injury [odds ratio (OR)=13.41, 95% confidence interval (CI)=1.31-136.78], temporal lobe injury (OR=12.3, 95% CI=2.07-73.08), dominant hemisphere injury (OR=8.19, 95% CI=1.43-46.78), and bi-frontal lobe injury (OR=7.52, 95% CI=1.31-43.11). In the 11 post-traumatic hydrocephalus patients who underwent VPS, the final MMSE scores (17.7±6.8) substantially increased from the initial MMSE scores (11.2±8.6). Conclusion Presence of bi-frontal lobe injury, temporal lobe injury, dominant hemisphere injury, and contre-coup injury and severe parenchymal injury adversely influenced the final MMSE scores. They can be concluded to be poor prognostic factors in terms of cognitive function in TBI patients. Development of hydrocephalus aggravates cognitive impairment with unpredictable time of onset. Thus, close observation and routine image follow-up are mandatory for early detection and surgical intervention for hydrocephalus.