Seung Hun Sheen

Intraarterial abciximab for treatment of thromboembolism during coil embolization of intracranial aneurysms: outcome and fatal hemorrhagic complications.

OBJECTnExperience with intraarterial abciximab for the treatment of thromboembolism during endovascular coil embolization is limited. The authors report the outcome of intraarterial abciximab use, with an emphasis on fatal hemorrhagic complications.nnnMETHODSnBetween March 2003 and May 2006, the authors treated 606 aneurysms by using endovascular coil embolization, and in 32 (5.3%) of these aneurysms (31 patients) an intraarterial thrombus developed. Sixteen of these aneurysms were ruptured and the other 16 were unruptured. Arterial thrombi were totally occlusive in 3 and partially occlusive in the remaining 29 cases. Intraarterial abciximab was administered at a concentration of 0.2 mg/ml as a bolus of 4-15 mg over a period of 15-30 minutes.nnnRESULTSnComplete thrombolysis was achieved in 17 (53%) and partial thrombolysis in 15 (47%) of 32 lesions. Twenty-eight patients (90.3%) were asymptomatic after abciximab thrombolysis, but 3 had postprocedural rebleeding that occurred after abciximab treatment; all of these patients had recently experienced an aneurysm rupture. Of these patients, 1 displayed severe thrombocytopenia and the other 2 showed a > 25% reduction in platelet count after abciximab treatment.nnnCONCLUSIONSnIntraarterial abciximab is effective for the treatment of thromboembolic complications that occur during intracranial aneurysm coil insertion. Nevertheless, attention should be paid to prevent potentially fatal complications such as thrombocytopenia and hemorrhage, especially in patients with a ruptured aneurysm.

Decrease in dystrophin expression prior to disruption of brain-blood barrier within the rat piriform cortex following status epilepticus.

Increased permeability of the brain-blood barrier (BBB) in the piriform cortex (PC) has been reported in various animal models of temporal lobe epilepsy. Since BBB disruption induced by epileptogenic insult has not fully clarified, we attempted to determine whether changes in BBB-related molecules are associated with vasogenic edema in the PC. One day after status epilepticus (SE), PC neurons and astrocytes showed a pyknotic nucleus and shrunken cytoplasm accompanied by vasogenic edema. At this time point, SMI-71 (an endothelial barrier antigen) immunoreactivity had decreased in the PC. Prior to vasogenic edema formation (12 h after SE), dystrophin immunoreactivity disappeared within astrocytes, while the change in glial fibrillary acidic protein immunoreactivity was negligible. However, glucose transporter-1 (an endothelial cell marker) had increased at 12 h after SE. These findings indicate that dysfunction of dystrophin induced by SE may result in endothelial and astroglial damage with BBB breakdown and increase vascular permeability, leading to vasogenic edema that is involved in pathogenesis of epileptogenesis.

Simple oblique lumbar magnetic resonance imaging technique and its diagnostic value for extraforaminal disc herniation.

Study Design. Prospective study evaluating the oblique lumbar magnetic resonance imaging (MRI). Objective. To present the technique of oblique lumbar MRI and assess the clinical efficacy of this technique for diagnosis of extraforaminal disc herniation. Summary of Background Data. Herniated lumbar discs are traditionally diagnosed using conventional lumbar axial and sagittal MRI. However, conventional lumbar MRI might not reveal nerve root compression in the extraforaminal area. Oblique lumbar MRI can provide clear visualization of the dorsal root ganglion and lumbar nerve root in the foraminal and extraforaminal areas. Methods. Ten patients diagnosed with extraforaminal disc herniations underwent bilateral oblique lumbar MRIs before surgery (turbo spin-echo T2-weighted sequence). We compared the side with symptomatic extraforaminal disc herniation to the asymptomatic contralateral side. Results. Oblique lumbar MRI succeeded in depicting pedicles, dorsal root ganglions, and lumbar nerve roots of the foraminal and extraforaminal areas. In 9 of 10 patients (90.0%), nerve root compression by the herniated disc in the extraforaminal area was clearly demonstrated when compared with the asymptomatic contralateral side (P < 0.05). In 1 patient with scoliosis and spinal stenosis, oblique MRI could not clearly display foraminal or extraforaminal anatomy due to spinal deformity. Conclusion. In light of this data, we suggest that oblique lumbar MRI can precisely demonstrate nerve roots in foraminal and extraforaminal areas. This technique is a simple and useful diagnostic tool for extraforaminal lumbar disc herniations.

Enhanced glial fibrillary acidic protein-δ expression in human astrocytic tumor

Astrocytic tumor is one of the most common primary tumors of the adult brain. Although there are several biochemical markers for the categorization of astrocytic tumor, few markers are used for histopathological diagnosis. Therefore, we evaluated glial fibrillary acidic protein (GFAP)-delta, a product of alternative splicing variants of GFAP-alpha, as a diagnostic marker. GFAP-delta immunoreactive (GFAP-delta(+)) astrocyte was rarely detected in tissue samples from autopsy controls. In tissue samples from patients with low-grade astrocytic tumor (grades I and II), GFAP-delta(+) cells appeared stellate, polygonal or round shape. In tissue samples from patients with high-grade astrocytic tumor (grades III and IV), GFAP-delta(+) cells showed round or spindle shape. GFAP-delta immunoreactivities in grades III and IV astrocytic tumor cells were increased by 1.4- and 1.7-fold in comparison to grade I astrocytic tumor cells. GFAP-delta immunoreactivity was also observed in cell bodies along the margins of astrocytic tumor showing normal histological findings, even though astroglia had normal morphology (showing strong GFAP and glutamine synthase immunoreactivities and a stellate shape with well-developed processes). Furthermore, the malignancy of astrocytic tumor was directly correlated with the degree of GFAP-delta immunoreactivity. These findings suggest that GFAP-delta may be a useful diagnostic marker for the evaluation of functional cataplasia or proliferation of astrocytic tumor.

Morphological changes of injected calcium phosphate cement in osteoporotic compressed vertebral bodies

SummaryThis study was undertaken to investigate the radiologic and clinical outcomes of vertebroplasty with calcium phosphate (CaP) cement in patients with osteoporotic vertebral compression fractures. The morphological changes of injected CaP cement in osteoporotic compressed vertebral bodies were variable and unpredictable. We suggest that the practice of vertebroplasty using CaP should be reconsidered.IntroductionRecently, CaP, an osteoconductive filler material, has been used in the treatment of osteoporotic compression fractures. However, the clinical results of CaP-cement-augmented vertebrae are still not well established. The purpose of this study is to assess the clinical results of vertebroplasty with CaP by evaluating the morphological changes of CaP cement in compressed vertebral bodies.MethodsFourteen patients have been followed for more than 2xa0years after vertebroplasty. The following parameters were reviewed: age, sex, T score, compliance with osteoporosis medications, visual analog scale score, compression ratio, subsequent compression fractures, and any morphological changes in the filler material.ResultsThe morphological changes of injected CaP included reabsorption, condensation, bone formation (osteogenesis), fracture of the CaP solid hump, and heterotopic ossification. Out of 14 patients, 11 (78.6%) developed progression of the compression of the CaP-augmented vertebral bodies after vertebroplasty.ConclusionsThe morphological changes of the injected CaP cement in the vertebral bodies were variable and unpredictable. The compression of the CaP-augmented vertebrae progressed continuously for 2xa0years or more. The findings of this study suggest that vertebroplasty using CaP cement should be reconsidered.

Comparison of different microanastomosis training models : model accuracy and practicality.

OBJECTIVEnThe authors evaluated the accuracies and ease of use of several commonly used microanastomosis training models (synthetic tube, chicken wing, and living rat model).nnnMETHODSnA survey was conducted among neurosurgeons and neurosurgery residents at a workshop held in 2009 at the authors institute. Questions addressed model accuracy (similarity to real vessels and actual procedures) and practicality (availability of materials and ease of application in daily practice). Answers to each question were rated using a 5-point scale. Participants were also asked what types of training methods they would chose to improve their skills and to introduce the topic to other neurosurgeons or neurosurgery residents.nnnRESULTSnOf the 24 participants, 20 (83.3%) responded to the survey. The living rat model was favored for model accuracy (p < 0.001; synthetic tube -0.95 +/- 0.686, chicken wing, 0.15 +/- 0.587, and rat, 1.75 +/- 0.444) and the chicken wing model for practicality (p < 0.001; synthetic tube -1.55 +/- 0.605, chicken wing, 1.80 +/- 0.523, and rat, 1.30 +/- 0.923). All (100%) chose the living rat model for improving their skills, and for introducing the subject to other neurosurgeons or neurosurgery residents, the chicken wing and living rat models were selected by 18 (90%) and 20 (100%), respectively.nnnCONCLUSIONnOf 3 methods examined, the chicken wing model was found to be the most practical, but the living rat model was found to represent reality the best. We recommend the chicken wing model to train surgeons who have mastered basic techniques, and the living rat model for experienced surgeons to maintain skill levels.

Intraarterial Tirofiban Thrombolysis for Thromboembolisms During Coil Embolization for Ruptured Intracranial Aneurysms

Objective Thromboembolus can occur during endovascular coil embolization. The aim of our study was to show our experience of intraarterial (IA) tirofiban infusion for thromboembolism during coil embolization for ruptured intracranial aneurysms. Methods This retrospective analysis was conducted in 64 patients with ruptured aneurysms who had emergent endovascular coil embolization from May 2007 to April 2011 at a single institute. Thromboembolic events were found in ten patients (15.6%). Anticoagulation treatment with intravenous heparin was started after the first coil deployment in ruptured aneurysmal sac. When a thrombus or embolus was found during the procedure, we tried to resolve them without delay with an initial dosage of 0.3 mg of tirofiban up to 1.2 mg. Results Three patients of four with total occlusion had recanalizations of thrombolysis in myocardial infarction (TIMI) grade III and five of six with partial occlusion had TIMI grade III recanalizations. Eight patients showed good recovery, with modified Rankin Scale (mRS) score of 0 and one showed poor outcome (mRS 3 and 6). There was no hemorrhagic or hematologic complication. Conclusion IA tirofiban can be feasible when thromboembolic clots are found during coil embolization in order to get prompt recanalization, even in patients with subarachnoid hemorrhage.

Extracorporeal Membrane Oxygenation for Acute Life-Threatening Neurogenic Pulmonary Edema following Rupture of an Intracranial Aneurysm

Neurogenic pulmonary edema (NPE) leading to cardiopulmonary dysfunction is a potentially life-threatening complication in patients with central nervous system lesions. This case report describes a 28-yr woman with life-threatening fulminant NPE, which was refractory to conventional respiratory treatment, following the rupture of an aneurysm. She was treated successfully with extracorporeal membrane oxygenation (ECMO), although ECMO therapy is generally contraindicated in neurological injuries such as brain trauma and diseases that are likely to require surgical intervention. The success of this treatment suggests that ECMO therapy should not be withheld from patients with life-threatening fulminant NPE after subarachnoid hemorrhage.

Feasibility of Intravenous Flat Panel Detector CT Angiography for Intracranial Arterial Stenosis

BACKGROUND AND PURPOSE: IV FDCT angiography is an emerging technology for the detection of intracranial vascular disease. This study was conducted to determine the feasibility of IV FDCT in estimating major atherosclerotic intracranial arterial stenosis with DSA as the reference. MATERIALS AND METHODS: DSA and IV FDCT were performed simultaneously in patients with transient ischemic attack or acute cerebral infarction. The degree and length of stenosis were measured. The stenotic vessels were categorized into 4 groups by the grade of stenosis: normal (<30%), mild (30%–49%), moderate (50%–69%), or severe (>70%). The vessels of the normal group were excluded from analysis to reduce spectrum bias. Measurement of vessels was recorded by using an electric ruler by a qualified endovascular neurosurgeon and a neuroradiologist. RESULTS: Eight hundred forty-two vessel segments in 69 patients were calculated. Mild (n = 56), moderate (n = 47) and severe stenosis (n = 46) groups were analyzed. IV FDCT had a sensitivity of 97.6%, specificity of 96.9%, and negative predictive value of 96.9% for detecting ≥50% stenosis and respective values of 91.9%, 98.2%, and 97.4% for depicting ≥70% stenosis. The difference of stenotic length between the 2 tests was not significant as an increase in the severity of stenosis (Spearman rank correlation test; r = −0.12, P = .13). CONCLUSIONS: IV FDCT can be a feasible alternative as a noninvasive method for evaluating stenosis of the major intracranial arteries.

Two-year follow-up of contrast stasis within the sac in unruptured aneurysm coil embolization: progressive thrombosis or enlargement?

BACKGROUND AND PURPOSE: The fate of contrast stasis within an aneurysmal sac after coiling has not been established. We followed and evaluated the potential risks of recanalization of unruptured aneurysms embolized with BPCs for 2 years. MATERIALS AND METHODS: A total of 301 unruptured aneurysms in 252 patients were treated with BPCs. Contrast stasis was observed on initial postembolization angiograms in 104 (34.6%) of these aneurysms. For follow-up, skull images by an angiographic unit (at 3, 9, 15, and 21 months), CE-MRA including TOF source images (at 6, 12, and 18 months), and DSA (at 24 months) were used. RESULTS: In 89 (85.6%) of the 104 aneurysms with contrast stasis, the stasis disappeared on 6-month MRAs and occlusions remained unchanged without recanalization for 2 years. In the remaining 15 (14.4%), recanalization occurred during follow-up. The presence of contrast stasis was not found to be associated with the obliteration rate (P = .641) or packing attenuation (aneurysms without contrast stasis 30.7% ± 11.18 versus aneurysms with contrast stasis 33.0% ± 12.11, P = .113). Contrast stasis was not found to be a risk factor for recanalization (15/104 [14.4%] versus 29/197 [14.7%], P = 1.000). CONCLUSIONS: Contrast stasis is a benign angiographic finding that can disappear within 6 months on follow-up MRA. In addition, contrast stasis was not found to be associated with a low obliteration rate or packing attenuation or to be a risk factor for recanalization. The present study shows that aneurysms with contrast stasis on initial postembolization angiograms are no more likely to recanalize than aneurysms without contrast stasis.