NI-16 RESPONSE ASSESSMENT OF BEVACIZUMAB THERAPY FOR GLIOBLASTOMA BY USING MULTIPLE PET TRACERS

Objective

PET scans are useful for the diagnosis and treatment planning of glioma. Introduced in 2013, bevacizumab (Bev) treatment efficacy can be difficult to determine using MRI imaging. We instead performed PET scans to determine the efficacy of Bev-based glioblastoma treatment.

Methods

Eighty glioblastoma patients treated with Bev from July 2013 to December 2021 were included. The patients were divided into the following three groups: the first group received Bev added to the Stupp regimen after biopsy or subtotal resection (first-dose group), the second group received Bev added to the Stupp regimen after biopsy followed by tumor resection (neoadjuvant group), and the third group received the Stupp regimen after tumor resection followed by TMZ + Bev at recurrence (recurrent group). PET scans (FDG, MET, FLT, and FMISO) were performed before and 4 weeks after the start of the Bev treatment. FDG, MET, and FLT measured tumor-to-normal ratio (TNR), and FMISO measured tumor-to-blood ratio (TBR), as well as the percent change in SUVmax, TNR, TBR, and MTV before and after Bev treatment. Using the Cox proportional hazards model, we examined which of these rates of change were the prognostic factors.

Results

The median PFS (months) and median OS from Bev treatment were 8.87, 16.53, and 4.0 and 12.53, 22.13, and 8.0, respectively. Significant differences in the percent change in MTV for MET, FLT, and FMISO in the first-line group, the percent change in MTV for FDG and MET, the percent change in FDG TNR and FMISO TBR in the recurrent group, and the percent change in MTV for MET and FLT in the neoadjuvant group were shown in the Cox proportional hazards model.

Conclusion

Neoadjuvant treatment with Bev prolonged PFS and OS. The decrease in MET MTV change rate and FMISO TBR.

Case Series of Endovascular Therapy for Blood Blister-Like Aneurysm in Acute Phase

Objective

Blood blister-like aneurysms (BBAs) of the internal carotid artery are highly challenging to treat due to their variable morphology and tendency for rupture and regrowth. Here, we report a single-institution experience of endovascular therapy (EVT) for BBA treatment.

Methods

We retrospectively reviewed patients with ruptured BBA from 2006 to 2019. All patients in whom BBA was treated with EVT were included. Patients' aneurysmal characteristics, progression status, aneurysm occlusion on follow-up angiography, and modified Rankin Scale (mRS) score were recorded.

Results

A total of 11 patients (5 women and 6 men) with the mean age of 46 ± 10 years were included in this study. As initial treatment, 9 patients were treated with stent-assisted coiling (SAC). Immediate angiographic results showed that 2 cases were body filling, 4 were neck remnant, and 3 were complete obliteration. Perioperative ischemic complications were not observed. On postoperative day 1, 2 patients suffered from rerupture, and their prognoses were poor. Retreatments were performed in 5 patients. Parent artery occlusion (PAO) was performed in 6 patients including 2 initial treatments and 4 retreatments. Symptomatic infarction developed in 2 patients. In 3 patients, bypass in combination with PAO was performed. Clinical data revealed discharge mRS scores of 0-2 and 3-6 in 4 and 7 patients, respectively.

Conclusion

SAC is effective for the management of BBA. Careful follow-up and response are necessary after treatment with SAC.

A preliminary study of relationship among the degree of internal carotid artery stenosis, wall shear stress on MR angiography and 18F-FDG uptake on PET/CT

BACKGROUND

This preliminary study was undertaken to evaluate relationship among the degree of internal carotid artery (ICA) stenosis, wall shear stress (WSS) by computational fluid dynamics (CFD) on magnetic resonance angiography (MRA) and 18F-FDG uptake of ICA on PET/CT.

METHODS

A total of 40 carotid arteries in 20 patients with carotid atherosclerotic disease were examined with MRA and 18F-FDG PET/CT. Atherosclerotic risk factors were assessed in all patients. Degree of ICA stenosis was calculated according to NASCET method. CFD analysis was performed and maximum WSS (WSSmax) was measured. 18F-FDG uptake in ICA was quantified using maximum target-to-blood pool ratio (TBRmax).

RESULTS

Atherosclerotic risk factors did not affect imaging findings. There were significant correlations between WSSmax and degree of ICA stenosis (ρ = .81, P < .001), WSSmax and TBRmax (ρ = .64, P < .001), and TBRmax and degree of ICA stenosis (ρ = .50, P = .001).

CONCLUSIONS

These preliminary results indicate that there may be significant correlations among the degree of ICA stenosis, WSSmax and TBRmax in patients with carotid artery stenosis.

Endovascular Treatment for Posterior Communicating Artery Aneurysms with Oculomotor Nerve Palsy

Objective

Coil embolization for the treatment of internal carotid artery-posterior communicating artery aneurysms (PComAAn) associated with oculomotor nerve palsy (ONP) remains controversial in terms of the therapeutic effect to improve ONP. Patients with PComAAn treated in our hospital were retrospectively analyzed to evaluate the effectiveness of coil embolization on ONP.

Methods

Twenty-three patients who had coil embolization for PComAAn with ONP were included in the analysis. In the evaluation of postoperative outcome of ONP, complete resolution of all symptoms was considered as a total recovery. ONP with a few residual symptoms that are stable and not disabling was considered as a subtotal recovery and that with only a slight improvement as a partial recovery.

Results

Preoperative ONP was complete palsy in 14 and partial palsy in nine cases. The mean maximum diameter of the aneurysms was 9.1 ± 3.5 mm (3-17 mm), and the mean time from the onset to treatment was 46.3 ± 98.4 days (0-300 days). The embolization state immediately after the procedure was complete occlusion in seven, neck remnant in eight, and body filling (BF) in eight cases. Total recovery was observed in nine, subtotal recovery in 11, and partial recovery in three cases. The mean time to any improvement in ONP was 6.0 ± 6.0 months (0.5-25 months). Comparing 20 cases with total plus subtotal recovery and three cases with partial recovery, five (25.0%) and three (100%) cases showed BF immediately after the procedure, respectively, which was statistically significant (P = 0.015).

Conclusion

The analysis indicated that coil embolization for the treatment of PComAAn with ONP resulted in satisfactory recovery of ONP in 87% of the cases and the outcome of aneurysm embolization was related to improvement in ONP.

Clinicopathologic Factors Associated with Tumor Necrosis after Preoperative Embolization of Meningiomas

Objective

Preoperative embolization of meningiomas induces necrosis prior to surgery and facilitates resection. Lack of contrast enhancement on postembolization MRI correlates with pathological findings of necrosis and can be used to assess embolization efficacy. This study aimed to examine clinicopathologic factors associated with tumor necrosis after embolization.

Methods

A total of 119 patients with intracranial meningioma who underwent 145 surgical resections between 2010 and 2019 at our institute were reviewed. Inclusion criteria for the study were preoperative embolization with trisacryl gelatin microspheres (Embosphere) or absorbable gelatine sponge (Gelfoam). Postembolization Gd-enhanced T1-weighted and angiographic imaging, and histopathologic examination results were reviewed to evaluate the effectiveness of embolization.

Results

In all, 66 patients satisfied the inclusion criteria. In total, 36 patients were embolized with Embosphere and 30 patients were embolized with Gelfoam. Patients embolized with Embosphere had a significantly higher necrosis rate (NR) than patients with Gelfoam (21% vs. 7.1%, P <0.01). The 36 Embosphere patients were analyzed regarding clinicopathologic factors associated with NR. Tumors in 12 patients were located in the parasagittal/falx region; these patients had a significantly lower NR compared with tumors in other locations (10.6% vs. 26.2%, P = 0.016). In all, 13 patients had feeders arising from only the middle meningeal artery (MMA), which was associated with a significantly higher NR (29.3% vs. 14.4%, P = 0.015). In total, 11 patients had meningeal feeders arising from internal carotid artery (ICA), which was associated with a significantly lower NR (9.0% vs. 26.3%, P <0.01).

Conclusion

This study showed embolization agent, tumor location, and blood supply were important factors predicting necrosis after preoperative embolization.

IMG-02. USEFUL DIAGNOSIS OF PEDIATRIC CYSTIC BRAIN TUMORS USING MULTIPLE POSITRON EMISSION TOMOGRAPHY STUDIES

OBJECTIVE

Pediatric brain tumors are primarily diagnosed using MRI or CT examination; however, determining the correct diagnosis using only morphological MRI can sometimes be challenging. Positron emission tomography (PET) uses radiotracers for metabolic and molecular imaging. We examined the accumulation of multiple PET (FDG, MET, FLT, and FMISO) studies for diagnosing pediatric cystic brain tumors.

METHODS

We performed PET scans for eight pediatric patients (five pilocytic astrocytoma, one pleomorphic xanthoastrocytoma, one diffuse astrocytoma with IDH1 mutation, one ganglioglioma) from April 2010 to December 2019. The resulting studies were compared by measuring the tumor-to-normal lesion (T/N) ratio of FDG, MET, and FLT and the tumor-to-blood value (T/B) ratio of FMISO between each pediatric cystic brain tumor.

RESULTS

All pediatric brain tumors showed tumor uptake of FDG, MET, and FLT. We could not examine FMISO PET for one diffuse astrocytoma with IDH1 mutation. The T/N ratios of FDG, MET, and FLT and the T/B ratio of FMISO were 1.07, 2.76, 4.6, and 1.12 for pilocytic astrocytoma; 0.65, 4.6, 7.67, and 1.38 for pleomorphic xanthoastrocytoma; 0.61, 2.14, and 3.82 for diffuse astrocytoma with IDH1 mutation; and 0.79, 1.78, 5, and 1.49 for ganglioglioma, respectively. The T/N ratios of MET and FLT for pleomorphic xanthoastrocytoma were high, but the Ki-67 labeling index was 1%. In the ganglioglioma, the T/N ratio of FLT was high, but the T/N ratio of MET was low.

CONCLUSION

Specialized multiple PET accumulation patterns for tumors are useful for discriminating each tumor.

GEN-09 Pursuing the function of microRNA targeting (Pro)renin receptor against glioma

(Pro)renin receptor((P)RR) is a part of the Wnt receptor complex. Wnt/β-catenin signaling pathway (Wnt signaling) plays important role in pathogenesis and self-renewal of glioblastoma (GBM), or differentiation of glioma stem cell. We previously reported that (P)RR activated Wnt signaling, (P)RR expression correlated with malignancy of glioma, and treatment with (P)RR siRNA reduced the proliferative capacity. This time, we have searched for over 2632 microRNAs by microRNA microarray that its expression is affected by (P)RR whether overexpressed or suppressed and examined their effects in GBM cell lines or its glioma stem cells.

NI-08 Utility of multiple positron emission tomography tracers in the diagnosis of brain tumors according to the 2016 World Health Organization classification

Objective: Magnetic resonance imaging alone is not sufficient for the diagnosis and therapy outcomes in brain tumors. We herein examined the utility of positron emission tomography (PET) studies for diagnosis in brain tumors. Methods: Between April 2009 and June 2020, 320 patients with central nervous diseases, including 140, 65, 52, 52, and 11 patients with glioma, metastatic brain tumor, malignant lymphoma, meningioma, and demyelinating disease, respectively, underwent PET studies (FDG, MET, FLT, and FMISO) in our department. Lesion/normal (L/N) ratios for FDG, MET, and FLT and lesion/blood ratio (L/B ratio) for FMISO were compared. The glioma subtypes were compared based on the 2016 World Health Organization classification (IDH-mut, Codel, IDH-wt, GBM), and metastatic brain tumors, malignant lymphomas, meningiomas, and demyelinating diseases were compared with GBM. Results: In glioma, the cutoff MET L/N ratios to distinguish between IDH-mut and Codel, IDH-mut and GBM, Codel and GBM, and IDH-wt and GBM were 3.61, 4.42, 4.92, and 4.33, respectively, and the cutoff FLT L/N ratios to distinguish between IDH-mut and IDH-wt, IDH-mut and GBM, Codel and GBM, and IDH-wt and GBM were 3.43, 6.46, 3.39, and 7.56, respectively. The cutoff FDG and MET L/N ratios between metastatic brain tumors and GBM were 2.27 and 4.89; the cutoff FDG L/N and FMISO L/B ratios between malignant lymphoma and GBM were 4.68 and 2.13; and the cutoff FDG and MET L/N ratios between meningioma and GBM were 1.58 and 4.36. Demyelinating disease and GBM were distinguishable by FDG, MET, and FLT L/N ratios of 2.29, 3.32, and 5.85, and FMISO L/B ratio of 1.68. Conclusion: Four PET tracers were required to differentiate glioma subtypes. FDG and MET are useful for distinguishing GBM from metastatic brain tumor, malignant lymphoma, and meningioma, whereas accumulation was lower for all four PET tracers in demyelinating diseases than in GBM.

NI-15 THE USEFULNESS OF PET IMAGING IN MOLECULAR DIAGNOSIS OF GLIOMA

OBJECTIVE

After WHO 2016 Classification of Tumors of the Central Nervous System have published, molecular diagnosis became part of the diagnostic criteria. In this study, we investigated the correlation between PET images and molecular diagnosis of glioma.

METHODS

We performed retrospective review of newly diagnosed supratentorial glioma patients who preoperatively underwent all four PET examinations (18F-FDG, 11C-MET, 18F-FLT and 18F-FMISO) from April 2009 to March 2019. The standardized uptake value (SUV) from the accumulation of each PET tracers, TNR (tumor to contralateral normal tissue ratio) of 18F-FDG,11C-MET and 18F-FLT, TBR (tumor to blood values ratio) of 18F-FMISO were measured. We investigated the correlation between these PET images and molecular diagnosis of glioma.

RESULTS

Data from total of 79 patients which were 42 cases of IDH wild type glioblastoma, 2 cases of IDH mutated glioblastoma, 9 cases of IDH wild type astrocytoma, 13 cases of IDH mutated astrocytoma and 13 cases of IDH mutated and 1p/19q co-deleted oligodendroglioma were included in this study. Both TNR of 11C-MET(p&lt;0.01) and 18F-FLT(p&lt;0.01), and also TBR of 18F-FMISO(p&lt;0.01) in IDH wild type gliomas showed significantly higher than IDH mutated gliomas. In WHO Gr2-3 gliomas, only TNR of 18F-FLT showed a significant difference between IDH wild type gliomas and IDH mutated gliomas(p&lt;0.01). TNR of 18F-FLT(p&lt;0.01) and TBR of 18F-FMISO(p&lt;0.01) in 1p/19q co-deleted gliomas were significantly lower than gliomas without 1p/19q co-deletion, but there were no significant differences in WHO Gr2-3 gliomas. Among IDH mutated gliomas, TNR of 11C-MET in 1p/19q co-deleted gliomas showed significantly higher uptake than gliomas without 1p/19q co-deletion(p&lt;0.05).

CONCLUSION

Preoperative PET evaluation of each PET tracers may be useful for the molecular diagnosis of glioma.

Serial blood lactate measurements and its prognostic significance in intensive care unit management of aneurysmal subarachnoid hemorrhage patients

PURPOSE

This study assesses the behavior of serial blood lactate measurements during intensive care unit (ICU) stay to identify prognostic factors of unfavorable neurological outcomes (UO) in patients with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

We retrospectively reviewed all patients who were consecutively hospitalized with SAH between 2009 and 2016. Arterial blood lactate levels were routinely obtained on admission and every 6h in the ICU. Univariate/multivariate analyses were performed to identify independent predictors of UO (modified Rankin scale of 3-6 upon hospital discharge).

RESULTS

There were 145 patients with 46% of UO. Initially, increased lactate levels reached maximum levels during the first 24h and then decreased to within the normal range. Then, the levels slightly increased again to within the normal range for the next 24h, especially in UO. On multiple regression analysis, lactate levels measured at 24h, and 48h after admission were strong predictors of UO. Lactate level measured at 48h after admission demonstrated the greatest accuracy and the highest specificity (area under the curve, 0.716; sensitivity, 40%; specificity, 92.1%).

CONCLUSIONS

The lactate level at 48h after admission was the most accurate predictor of UO with a high specificity in SAH patients.

Cavernous sinus dural arteriovenous fistula treated by facial vein direct puncture: Case report and review of the literature

Introduction In case of cavernous sinus dural arteriovenous fistula (CSDAVF), transvenous embolization (TVE) of the cavernous sinus (CS) via the inferior petrosal sinus (IPS) is generally performed. However, various approach routes have been reported when the accessibility of the IPS is challenging. We herein report a case of CSDAVF treated by TVE with direct puncture of the facial vein. Case report A 70-year-old woman who suffered from tinnitus, chemosis, diplopia and bruit was referred to our hospital. Digital subtraction angiography (DSA) demonstrated CSDAVF. We initially attempted to perform TVE via the IPS route; however, we could not guide a catheter to the CS because of an anatomical difficulty. Then, we performed percutaneous direct puncture of the dilated facial vein, and successfully treated the patient. Conclusion When navigating microcatheter to the CS is difficult because of an anatomical difficulty of the IPS, direct puncture of the facial vein is a feasible route.

Blood Glucose Variability: A Strong Independent Predictor of Neurological Outcomes in Aneurysmal Subarachnoid Hemorrhage

PURPOSE

In patients with aneurysmal subarachnoid hemorrhage (SAH), increased glucose variability (GV) is associated with increased mortality and cerebral infarction; however, there are no reports demonstrating an association between GV and neurological outcome. This study investigated whether GV had an independent effect on neurological outcomes in patients with SAH in the intensive care unit.

MATERIALS AND METHODS

Consecutive adult patients hospitalized with SAH between January 1, 2009, and May 31, 2015 (N = 122) were retrospectively reviewed. Univariate/multivariate analyses were performed to identify independent predictors of poor neurological outcome. Patients were divided according to the mean glucose level (80-139 vs 140-200 mg/dL) and further subdivided using quartiles (Q) of the standard deviation (SD, representing variability) of the glucose level (Q1, Q2 + 3, and Q4).

RESULTS

Unfavorable neurological outcomes occurred in 44.2% of the patients. On multiple regression analysis, age, Hunt and Kosnik grade, SD of glucose (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.02-1.17; P < .01), and minimum blood glucose level (OR, 0.95; 95% CI, 0.91-0.99; P < .01) were significantly associated with unfavorable neurological outcomes. Both groups (mean glucose levels: 80-139 and 140-200 mg/dL groups) had increasing unfavorable neurological outcomes with increasing SD of glucose (Q1, 15.0%; Q2 + 3, 40.0%; Q4, 52.4% and Q1, 44.4%; Q2 + 3, 50%; Q4, 88.9% in the 80-139 and 140-200 mg/dL groups, respectively). Patients with minimum glucose of <90 mg/dL comprised >50% of unfavorable neurological outcome.

CONCLUSION

Increased GV was an independent predictor of unfavorable neurological outcomes in patients with SAH.

Impact of neurointensivist-managed intensive care unit implementation on patient outcomes after aneurysmal subarachnoid hemorrhage

PURPOSE

The purpose of the study is to evaluate the impact of neurointensivist-managed intensive care unit (NIM-ICU) implementation for patients admitted with aneurysmal subarachnoid hemorrhage (SAH).

METHODS

This study retrospectively evaluated 234 patients (mean age, 61.7 years; male, 67) admitted with SAH between January 1, 2001, and March 31, 2014. Neurologic outcomes between patients admitted from January 2001 to December 2006 (intensivist-managed intensive care unit group) and January 2007 to March 2014 (NIM-ICU group) were compared. The primary outcome was the incidence of a good neurologic outcome at discharge (GO; the modified Ranking Scale score: GO, 0-2; poor neurological outcome, 3-6) at discharge.

RESULTS

Neurointensivist-managed intensive care unit was initiated for 151 (64.5%) of 234 patients. Univariate analysis demonstrated significantly better outcomes for NIM-ICU group vs intensivist-managed intensive care unit group (GOs, 58.3% vs 41.0%, respectively, P = .01). Multivariate logistic regression was used to evaluate NIM-ICU efficacy for SAH patients, but NIM-ICU was not significantly associated with GOs (P = .054). Subgroup analysis of patient grading by Hunt and Kosnik grades I to II showed that NIM-ICU implementation was an independent predictor of GOs (odds ratio, 4.54; 95% confidence interval, 1.08-22.17; P = .04).

CONCLUSION

Neurointensivist-managed intensive care unit may improve neurologic outcomes in SAH patients with Hunt and Kosnik grades I to II.

Deferoxamine reduces intracerebral hemorrhage-induced white matter damage in aged rats

Iron contributes to c-Jun N-terminal kinases (JNK) activation in young rats and white matter injury in piglets after intracerebral hemorrhage (ICH). In the present study, we examined the effect of deferoxamine on ICH-induced white matter injury and JNK activation and in aged rats. Male Fischer 344 rats (18months old) had either an intracaudate injection of 100μl of autologous blood or a needle insertion (sham). The rats were treated with deferoxamine or vehicle with different regimen (dosage, duration and time window). White matter injury and activation of JNK were examined. We found that a dose of DFX should be at more than 10mg/kg for a therapeutic duration more than 2days with a therapeutic time window of 12h to reduce ICH-induced white matter loss at 2months. ICH-induced white matter injury was associated with JNK activation. The protein levels of phosphorylated-JNK (P-JNK) were upregulated at day-1 after ICH and then gradually decreased. P-JNK immunoreactivity was mostly located in white matter bundles. ICH-induced JNK activation was reduced by DFX treatment. This study demonstrated that DFX can reduce ICH-induced JNK activation and white matter damage.

[Intrapituitary adenoma metastasis from lung cancer with progressive cranial nerve palsies: a case report and literature review]

We report a rare case of metastasis to a preexisting pituitary adenoma. An 80-year-old man with a history of pituitary adenoma and lung cancer presented with recent onset of bilateral visual impairment, oculomotor nerve palsies, and severe headache. A CT scan revealed a pituitary tumor expanding into the suprasellar region and infiltrating the bilateral cavernous sinuses. We performed transsphenoidal surgery and diagnosed the tumor as lung cancer metastasis to the pituitary adenoma. After the surgery, visual impairment and severe headache were resolved, and the patient underwent radiation therapy for the residual tumor. To the best of our knowledge, 20 cases of metastases to pituitary adenomas have been reported in the literature. Clinical features of metastasis to a pituitary adenoma are different from those of metastasis to normal pituitary gland. In the case of a pituitary lesion with acute aggravation, one should be aware of the possibility of metastasis to preexisting pituitary adenomas.

Deferoxamine reduces neuronal death and hematoma lysis after intracerebral hemorrhage in aged rats

Intracerebral hemorrhage (ICH) is primarily a disease of the elderly. Deferoxamine (DFX), an iron chelator, reduces long-term neurological deficits and brain atrophy after ICH in aged rats. In the present study, we investigated whether DFX can reduce acute ICH-induced neuronal death and whether it affects the endogenous response to ICH (ferritin upregulation and hematoma resolution) in aged rats. Male Fischer 344 rats (18 months old) had an intracaudate injection of 100 μL autologous whole blood into the right basal ganglia and were treated with DFX (100 mg/kg) or vehicle 2 hours post-ICH and then every 12 hours up to 7 days. Rats were euthanized 1, 3, or 7 days later for neuronal death, ferritin and hematoma size measurements. Plasma ferritin levels and behavioral outcome following ICH were also examined. DFX treatment significantly reduced ICH-induced neuronal death and neurological deficits. DFX also suppressed ferritin upregulation in the ipsilateral basal ganglia after ICH and hematoma lysis (hematoma volume at day 7: 13.2±4.9 vs. 3.8±1.2 mm3 in vehicle-treated group, p<0.01). However, effects of DFX on plasma ferritin levels after ICH did not reach significance. In conclusion, DFX reduces neuronal death and neurological deficits after ICH in aged rats. It also affects the endogenous response to ICH.

Treatment of acute cerebral artery occlusion using the Penumbra system: our early experience

Intravenous recombinant tissue-type plasminogen activator (rt-PA) therapy is highly recommended to patients who are diagnosed with ischemic stroke within 4.5 hours after the onset while mechanical clot retrieval can be attempted in patients who are not indicated for or cannot effectively receive intravenous rt-PA therapy. In this article, we report early treatment outcomes and discuss the usefulness of mechanical clot retrieval using the Penumbra system (Penumbra Inc., Alameda, California, USA), especially in terms of technical cautions during the procedure and adaptability to elderly and high National Institutes of Health Stroke Scale (NIHSS) patients. We included 7 patients with thromboembolic occlusion. Pre-treatment NIHSS score ranged from 11 to 36 (mean: 24.9). All patients achieved good recanalization [thrombolysis in cerebral infarction (TICI) grade 2a or greater] without complications. The NIHSS score at 30 days after the treatment ranged between 0 and 28 (mean: 12.4), and improved more than 10 points in 4 of the 7 patients (57.1%). To obtain good recanalization without complications, selection of suitable reperfusion catheter and careful manipulation of separator prefiguring the occluded distal vessels are essential. The improved NIHSS score at 30 days after the treatment may have led to favorable results, such as an increased participation in available rehabilitation programs and the alleviation of the burden of care. Our findings suggest that the Penumbra system might be effective for treatment in elderly patients or patients with high NIHSS score wherein rt-PA therapy is inadvisable or ineffective in ischemic stroke secondary to large vessel occlusion. Recanalization can improve their quality of life on condition that the procedure is performed successfully without serious complications.

Cerebral blood flow and oxygen metabolism measurements using positron emission tomography on the first day after carotid artery stenting

BACKGROUND

The aim of the present study is the characterization of hemodynamics to predict hyperperfusion syndrome (HPS) after carotid artery stenting (CAS) with positron emission tomography (PET) obtained before and on the first day after the treatment.

METHODS

Cerebral perfusion and oxygen metabolism were evaluated by (15)O-gas PET in 18 patients with symptomatic internal carotid artery (ICA) stenosis before and on the first day after CAS. Regional cerebral blood flow (CBF), oxygen extraction fraction (OEF), cerebral metabolic rate of oxygen (CMRO2), and cerebral blood volume (CBV) were measured in the ipsilateral and contralateral middle cerebral artery territories and compared between before and after CAS.

RESULTS

CBF increased in 16 of 18 patients on the first day after CAS and postoperative CBF was significantly higher than preoperative CBF bilaterally. OEF decreased in 15 of 18 patients on the first day after CAS and postoperative OEF was significantly lower than preoperative OEF in the ipsilateral hemisphere. CMRO2 and CBV did not change significantly. None of the patients showed HPS after CAS. All patients who had preoperative OEF of 53% or more (misery perfusion) in the ipsilateral hemisphere showed 50% or more increase in CBF postoperatively. The preoperative OEF value significantly correlated with the rate of postoperative increase in CBF bilaterally.

CONCLUSIONS

CAS increases cerebral perfusion and improves hemodynamic compromise in patients with symptomatic ICA stenosis. Although we could not clarify the usefulness of PET before and on the first day after CAS in predicting HPS, a high preoperative OEF is related to postoperative marked CBF increase and might be used as a predictor of HPS. Patients with greater hemodynamic compromise with a high preoperative OEF should be managed carefully to prevent HPS, but they have a greater chance of CBF increase after CAS.

Usefulness of L-[methyl-11c]methionine positron emission tomography in the treatment of idiopathic hypertrophic cranial pachymeningitis--case report

A 53-year-old man suffered from pulsating headache for 2 months. Magnetic resonance imaging with gadolinium revealed a linear or nodular mass along the left fronto-parietal convexity. Positron emission tomography (PET) with L-[methyl-11C]methionine (11C-MET) demonstrated increased uptake in the enhanced lesion. Biopsy, obtained by craniotomy, demonstrated granulation with lymphocyte and plasma cell infiltration, suggesting inflammatory changes, and a diagnosis of idiopathic hypertrophic cranial pachymeningitis (IHCP) was made. Steroid therapy resulted in improvement of the clinical symptoms and shrinkage of the enhanced lesion in a week. Follow-up 11C-MET PET study, after 18 months of steroid therapy, demonstrated significantly decreased uptake in the lesion, so the steroid therapy was discontinued. Neither clinical nor radiological recurrence was observed one year after discontinuation of the steroid therapy. This case of IHCP with increased 11C-MET uptake, which then decreased after steroid therapy suggests that 11C-MET PET is a useful monitoring modality for therapeutic efficacy against IHCP, and can indicate the appropriate timing of therapy discontinuation.

[11C-methionine positron emission tomography in nontumorous brain lesions]

Positron emission tomography (PET) with L-[methyl-11C]methionine (MET) provides information on the metabolism of brain tumor. MET uptake reflects amino acid active transport and protein synthesis and is proportional to the amount of viable tumor cells. However, MET uptake can be increased as a result of increased density of inflammatory cells and disruption of the blood brain barrier (BBB) in nontumorous brain lesions. From October 2005 through November 2009, 438 MET-PET studies were performed for various brain lesions at our institution. Among them, 27 (6%) were finally diagnosed to be nontumorous by surgical exploration or their clinical course. Nine of 10 intracerebral hemorrhages and all 4 cerebral infarctions demonstrated mild to moderate MET uptake in or surrounding the lesions in the subacute or chronic stage after the ictus. Moderately increased MET uptake was observed in all 3 patients with brain abscess. Active lesions in multiple sclerosis and Beçhet disease showed mild MET uptake. Idiopathic orbital and optic inflammations showed mildly increased MET uptake in the lesions. Finally, a case of hypertrophic cranial pachymeningitis exhibited strong MET uptake in the lesions. We should keep in mind that high MET uptake is frequently observed in nontumorous brain lesions. Although differentiation from tumorous lesions is usually possible by laboratory and morphological examinations, nontumorous lesions should be included in the differential diagnosis when encountering patients with high MET uptake.

Deferoxamine treatment for intracerebral hemorrhage in aged rats: therapeutic time window and optimal duration

BACKGROUND AND PURPOSE

Deferoxamine (DFX) reduces brain edema, neurological deficits, and brain atrophy after intracerebral hemorrhage (ICH) in aged and young rats. Our previous study found that 50 mg/kg is an effective dose in aged rats. In the present study, we explored potential therapeutic time windows and optimal therapeutic durations.

METHODS

Aged male Fischer 344 rats (18 months old) sustained an intracaudate injection of 100 microL autologous whole blood, followed by intramuscular DFX or vehicle beginning at different time points, or continuing for different durations. Subgroups of rats were euthanized at day 3 for brain edema measurement and day 56 for brain atrophy determination. Behavioral tests were performed on days 1, 28, and 56 after ICH.

RESULTS

Systemic administration of DFX, when begun within 12 hours after ICH, reduced brain edema. DFX treatment started 2 hours after ICH and administered for >or=7 days attenuated ICH-induced ventricle enlargement, caudate atrophy, and neurological deficits. DFX attenuated ICH-induced brain atrophy and neurological deficits without detectable side effects when begun within 24 hours and administered for 7 days.

CONCLUSIONS

To the extent that these results can be translated to humans, the therapeutic time window and the optimal duration for DFX in this aged rat model of ICH may provide useful information for an ongoing DFX-ICH clinical trial.

Effects of deferoxamine on intracerebral hemorrhage-induced brain injury in aged rats

BACKGROUND AND PURPOSE

Deferoxamine (DFX) reduces brain edema, neuronal death, and neurological deficits after intracerebral hemorrhage (ICH) in young rats. In the present study, we investigated whether DFX is effective on brain injury after ICH in aged rats and examined dose dependency.

METHODS

Male Fischer 344 rats (18 months old) had an intracaudate injection of 100 microL autologous whole blood and were treated with different doses of DFX (10, 50, and 100 mg/kg) or vehicle 2 and 6 hours post-ICH and then every 12 hours up to 7 days. Rats were euthanized at Day 3 for brain edema determination and Day 56 for brain atrophy measurement. Behavioral tests were performed during the experiments.

RESULTS

All 3 doses of DFX attenuated perihematomal brain edema at 3 days (eg, at dose 50 mg/kg, 80.4+/-0.5 versus 81.6+/-0.9% in the vehicle-treated group, P<0.01). Fifty and 100 mg/kg DFX also reduced ICH-induced ventricle enlargement, caudate atrophy, and ICH-induced neurological deficits in aged rats. However, although 10 mg/kg DFX reduced ventricle enlargement and forelimb-placing deficits, it did not reduce caudate atrophy and corner turn deficits.

CONCLUSIONS

These results indicate that DFX can reduce ICH-induced brain injury in aged as well as young rats and that a dose >10 mg/kg is the optimal dose of DFX in this model.

Tissue-type transglutaminase and the effects of cystamine on intracerebral hemorrhage-induced brain edema and neurological deficits

Neurodegeneration occurs after intracerebral hemorrhage (ICH) and tissue-type transglutaminase (tTG) has a role in neurodegenerative disorders. The present study investigated tTG expression after ICH and the effects of a tTG inhibitor, cystamine, on ICH-induced brain edema and neurological deficits. This study has two parts. In the first, male Sprague-Dawley rats received an intracaudate injection of 100 microL autologous whole blood or a needle insertion (sham). Rats were killed 3 days later and the brains used for immunohistochemistry, Western blots and real-time quantitative polymerase chain reaction. In the second set, ICH rats were treated intraperitoneally with either a tTG inhibitor, cystamine, or vehicle. Rats underwent behavioral testing and were killed at day-3 for measurement of brain swelling. tTG positive cells were found in the ipsilateral basal ganglia after ICH and most of those cells were neuron-like. Western blot analysis showed a 3-fold increase in tTG in the ipsilateral basal ganglia (p<0.01 vs. sham) after ICH. tTG mRNA levels were also significantly higher (8.5-fold increase vs. sham). Cystamine treatment attenuated ICH-induced brain swelling (day 3: 14.4+/-3.2 vs. 21.4+/-4.0% in vehicle-treated rats, p<0.01), neuronal death and improved functional outcome (forelimb placing score: 47+/-23 vs. 17+/-16% in vehicle-treated rats, p<0.05). ICH induces perihematomal tTG upregulation and cystamine, a tTG inhibitor, reduces ICH-induced brain swelling and neurological deficits.

Neurological deficits and brain edema after intracerebral hemorrhage in Mongolian gerbils

We examined the time course of neurological deficits in gerbils after an intracerebral hemorrhage (ICH) induced by autologous blood infusion and examined its correlation with the severity of perihematomal edema. Mongolian gerbils (n = 15) were subjected to stereotaxic autologous blood infusion (30 or 60 microL) into the left caudate nucleus. Corner-turn and forelimb-placing tests were performed before, and 1 and 3 days after ICH. Perihematomal water content was measured by tissue gravimetry. Gerbils developed neurological deficits and perihematomal edema at day 1 after ICH. Both neurological deficits and perihematomal edema were significantly greater in animals with 60 microL blood infusion compared to the 30 microL infusion group, and both neurological deficits and edema were also greater at 3 days compared to 1 day after ICH. The severity of neurological deficits paralleled the degree of perihematomal edema. We conclude that the Mongolian gerbil is a suitable model for studies on the behavioral effects of ICH.

Effects of mild hypothermia and alkalizing agents on brain injuries in rats with acute subdural hematomas

Brain ischemia is the leading pathopysiological mechanism in the development of secondary brain damage after acute subdural hematoma (SDH). Hypothermia has been employed as an effective cerebroprotective treatment on brain injuries, but the control of the general condition is very difficult under hypothermia, and various severe complications have been reported. Cerebral acidosis in the ischemic area is one of the important factors augmenting the brain edema formation. Tris-(hydroxymethyl)-aminomethane (THAM) has been used as an alkalizing agent for acidosis on brain injury and is reported to be effective. In the present study, we used a rat acute SDH model to assess the effect of mild (35 degrees C) hypothermia and THAM combined treatment on brain water content, brain ischemia, and blood-brain barrier (BBB) permeability at 4 h after hematoma induction. Mild hypothermia did not significantly reduce the brain water content beneath the hematoma (79.5 +/- 0.2%) compared to normothermia (80.2 +/- 0.2%), but mild hypothermia combined to THAM resulted in a significant reduction (78.7 +/- 0.0%; p < 0.01). Combined with mild hypothermia, THAM treatment significantly reduced the Evan's blue extravasation (35 +/- 7 ng/g wet tissue; p < 0.05) compared to normothermia (63 +/- 7 ng/g wet tissue). Furthermore, the volume of infarction at 24 h after the hematoma induction (54 +/- 3 mm(3); p < 0.01) was significantly smaller by the combined treatment compared with normothermia (70 +/- 2 mm(3)). The present findings indicate that mild hypothermia of 35 degrees C combined with THAM presents a potent cerebroprotective strategy. The protection of the BBB is one of the possible cerebroprotective mechanisms in this rat acute SDH model.

Effects of hypothermia on intracranial hemodynamics and ischemic brain damage-studies in the rat acute subdural hematoma model

Brain ischemia is the leading pathophysiological mechanism in the development of secondary brain damage after subdural hematoma (SDH). Hypothermia has been used as the effective neuroprotective treatment in clinical and laboratory studies of ischemic brain injury. In this study, we have examined the rat acute SDH model to assess the effect of hypothermia upon intracranial hemodynamics and also upon ischemic brain injury 4 hours after the induction of hematoma. Moderate hypothermia (32 degrees C) did not affect the intracranial pressure nor cerebral perfusion pressure, and it significantly reduced cortical brain edema formation underneath the hematoma (80.88 +/- 0.17%; p < 0.01) compared with the normothermic control group (81.65 +/- 0.52%). This reduction in brain edema formation was comparable to the result of MK-801 (2 mg/kg) treatment (80.95 +/- 0.35%; p < 0.01). Ischemic brain damage detected by H-E staining was also significantly reduced in the hypothermia and MK-801 treated groups (59.1 +/- 12.3 mm3 and 66.4 +/- 13.8 mm3; p < 0.01 and p < 0.05) compared with the normothermic control group (86.6 +/- 20.7 mm3). In conclusion, the present study demonstrates that hypothermia is a potent neuroprotective method and an inhibition of the glutamate excitotoxic process may contribute the protective mechanisms of hypothermia in this rat acute SDH model.

Protective effect of mild hypothermia on symptomatic vasospasm: a preliminary report

Mild hypothermia (32-34 degrees C of brain temperature) was used for brain protection in patients with progressive ischemic neurological deficits associated with severe cerebral vasospasm and who did not respond to medical treatment or intravascular angioplasty. Results showed that 2 of 3 patients in Hunt & Kosnik grade I to III and 2 patients who underwent delayed operation on day 5 and 9 each and had ischemic neurological deficits made good recovery with this treatment. Favourable outcome was obtained in 4 of 9 patients in grade IV and V. Mild hypothermia is thought to provide brain protection in critical ischemia due to severe cerebral vasospasm and can lengthen therapeutic time to employ angioplasty and intraarterial Papaverin infusion.

Effects of hypothermia on thrombin-induced brain edema formation

Recent studies have shown that thrombin plays an important role in brain edema formation after intracerebral hemorrhage (ICH). The possible mechanisms of thrombin-induced brain edema formation include blood-brain barrier (BBB) disruption and inflammatory response involving polymorphonuclear (PMN) leukocyte. Animal experiments have revealed that moderate therapeutic hypothermia improves pathological and functional outcome in various models of brain injury. In this study, we examined the effect of hypothermia on thrombin-induced brain edema formation. Effects of hypothermia on BBB permeability and the accumulation of PMN leukocytes were also determined to clarify the protective mechanism of hypothermia in this model. Anesthetized adult rats received an injection of 10 Units of thrombin into the basal ganglia. Animals were separated into the normothermic and hypothermic groups, which were housed in a room maintained at 25 degrees C and in a cold room maintained at 5 degrees C, respectively, for 24 h after the thrombin injection. The brain temperature in rats housed in a cold room reduced temporarily to approximately 30 degrees C and then gradually recovered to 35 degrees C by the end of the observation. Brain water content in the basal ganglia was significantly reduced in rats treated with hypothermia compared to the normothermic rats (84.3+/-0.2 vs. 82.4+/-0.1%; P<0.01). The decrease of brain water content was accompanied with a significant reduction in BBB permeability to Evan's blue dye and in accumulation of PMN leukocytes. This study indicates that hypothermic treatment significantly reduces thrombin-induced brain edema formation in the rat. Inhibition of thrombin-induced BBB breakdown and inflammatory response by hypothermia appear to contribute to brain protection in this model. Hypothermic treatment may provide an approach to potentially reduce ongoing edema after ICH.

Effects of delayed intraischemic and postischemic hypothermia on a focal model of transient cerebral ischemia in rats

BACKGROUND AND PURPOSE

Intraischemic mild hypothermia has been shown to be neuroprotective in reducing cerebral infarction in transient focal ischemia. As a more clinical relevant issue, we investigated the effect of delayed intraischemic and postischemic hypothermia on cerebral infarction in a rat model of reversible focal ischemia. We also examined the effect of hypothermia on the inflammatory response after ischemia-reperfusion to assess the neuroprotective mechanism of brain hypothermia.

METHODS

Rats were subjected to 2 hours of middle cerebral artery occlusion followed by 22 hours of reperfusion under the following protocols: (1) rats were treated with normothermia (37.0 degrees C, 4 hours) and then housed in room temperature (25 degrees C, 18 hours) and (2) rats were treated with hypothermia (33.0 degrees C, 4 hours, brain temperature modulation was started 30 minutes before the reperfusion) and then housed in cold temperature (5 degrees C, 18 hours). Animals were killed 24 hours after the onset of ischemia. The infarct volume was examined with 2,3,5-triphenyl-tetrazolium chloride staining. The accumulation of polymorphonuclear leukocytes (PMNLs) and the expression of intercellular adhesion molecule-1 mRNA were evaluated in both groups.

RESULTS

A significant reduction (P<0.05) in infarct volume was found in the hypothermia group compared with the normothermia group. Compared with the normothermia group, hypothermic treatment also significantly reduced the accumulation of PMNLs (P<0.01) and inhibited the overexpression of intercellular adhesion molecule-1 mRNA at 22 hours of reperfusion after 2 hours of ischemia.

CONCLUSIONS

Ischemic brain damage can be reduced with delayed intraischemic and prolonged postischemic hypothermia in a focal model of transient cerebral ischemia in rats. The neuroprotective mechanism of hypothermia may be mediated by suppression of PMNL-mediated inflammatory response after ischemia-reperfusion in this model.

Effects of hypothermia on intracranial pressure and brain edema formation: studies in a rat acute subdural hematoma model

Acute subdural hematoma (SDH) is the most common mass lesion in severe head injury, and brain ischemia is the leading pathophysiological mechanism in the development of secondary brain damage following SDH. Hypothermia has been employed as an effective neuroprotective procedure in clinical and laboratory studies on cerebral ischemic and contusional injuries. In the present study, we used a rat acute SDH model to assess the effect of hypothermia on the intracranial pressure (ICP) and also on the brain edema formation at 4 h after hematoma induction. Mild (34 degrees C) and moderate (32 degrees C) hypothermia did not significantly affect the ICP or cerebral perfusion pressure, but they were associated with a significant lower cortical brain edema formation beneath the hematoma (81.09 +/- 0.49%, p<0.05; and 80.88 +/- 0.17%, p<0.01) when compared with the normothermic control group (81.65 +/- 0.52%). This reduction in brain edema formation was comparable to the results of MK-801 treatment (80.95 +/- 0.35%, p<0.01). The present findings indicate that hypothermia represents a potent neuroprotective strategy. The possible protective mechanisms of hypothermic protection afforded in this rat acute SDH model are discussed.