The white-collar sign after Neuroform Atlas stent-assisted coil embolization of unruptured intracranial aneurysms.

PURPOSE: Although stent-assisted technique is expected to help provide a scaffold for neointima formation at the orifice of the aneurysm, not all aneurysms treated with stent-assisted technique develop complete neointima formation. The white-collar sign (WCS) indicates neointimal tissue formation at the aneurysm neck that prevents aneurysm recanalization. The aim of this study was to explore factors related to WCS appearance after stent-assisted coil embolization of unruptured intracranial aneurysms (UIAs). METHODS: A total of 59 UIAs treated with a Neuroform Atlas stent were retrospectively analyzed. The WCS was identified on digital subtraction angiography (DSA) 1 year after coil embolization. The cohort was divided into WCS-positive and WCS-negative groups, and possible predictors of the WCS were explored using logistic regression analysis. RESULTS: The WCS appeared in 20 aneurysms (33.9%). In the WCS-positive group, neck size was significantly smaller (4.2 (interquartile range (IQR): 3.8-4.6) versus 5.4 (IQR: 4.2-6.8) mm, p = .006), the VER was significantly higher (31.8% (IQR: 28.6%-38.4%) versus 27.6% (IQR: 23.6%-33.8%), p = .02), and the rate of RROC class 1 immediately after treatment was significantly higher (70% vs 20.5%, p < .001) than in the WCS-negative group. On multivariate analysis, neck size (odds ratio (OR): 0.542, 95% confidence interval (CI): 0.308-0.954; p = .03) and RROC class 1 immediately after treatment (OR: 6.99, 95% CI: 1.769-27.55; p = .006) were independent predictors of WCS appearance. CONCLUSIONS: Smaller neck size and complete occlusion immediately after treatment were significant factors related to WCS appearance in stent-assisted coil embolization for UIAs using the Neuroform Atlas stent.

An exploratory prospective phase II study of preoperative neoadjuvant bevacizumab and temozolomide for newly diagnosed glioblastoma.

PURPOSE: This multi-institutional phase I/II study was conducted to confirm the safety and explore the clinical utility of preoperative Bevacizumab (Bev) for newly diagnosed glioblastoma (GB). METHODS: Patients were enrolled based on magnetic resonance imaging (MRI) findings typically suggestive of GB. Preoperative Bev and temozolomide (TMZ) were administered at doses of 10 mg/kg on day 0 and 150 mg/m2 on days 1-5, respectively. Surgical resection was performed between days 21 and 30, inclusive. The safety and efficacy were evaluated in a total of 15 cases by progression-free survival (PFS), changes in tumor volume, Karnofsky Performance Scale (KPS) and Mini-Mental State Examination (MMSE) scores after preoperative therapy. RESULTS: Tumor resection was performed on a mean of day 23.7. Pathological diagnosis was GB, isocitrate dehydrogenase (IDH)-wildtype in 14 cases and GB, IDH-mutant in 1 case. Severe adverse events possibly related to preoperative Bev and TMZ were observed in 2 of the 15 patients, as wound infection and postoperative hematoma and thrombocytopenia. KPS and MMSE scores were significantly improved with preoperative therapy. Tumor volume was decreased in all but one case on T1-weighted imaging with contrast-enhancement (T1CE) and in all cases on fluid-attenuated inversion recovery, with mean volume decrease rates of 36.2% and 54.0%, respectively. Median PFS and overall survival were 9.5 months and 16.5 months, respectively. CONCLUSION: Preoperative Bev and TMZ is safe as long as the instructions are followed. The strategy might be useful for GB in some patients, not only reducing tumor burden, but also improving patient KPS preoperatively. TRIAL REGISTRATION NUMBER: UMIN000025579, jRCT1031180233 https://jrct.niph.go.jp/latest-detail/jRCT1031180233 . Registration Date: Jan. 16, 2017.

Predicting difficult transradial approach guiding into left internal carotid artery on unruptured intracranial aneurysms.

Background: The transradial approach (TRA) is less invasive than the transfemoral approach (TFA), but the higher conversion rate represents a drawback. Among target vessels, the left internal carotid artery (ICA) is particularly difficult to deliver the guiding catheter to through TRA. The purpose of this study was thus to explore anatomical and clinical features objectively predictive of the difficulty of delivering a guiding catheter into the left ICA via TRA. Methods: Among 78 consecutive patients who underwent coil embolization for unruptured intracranial aneurysms through TRA in a single institution between March 1, 2021, and August 31, 2022, all 29 patients (37%) who underwent delivery of the guiding catheter into the left ICA were retrospectively analyzed. Clinical and anatomical features were analyzed to assess correlations with difficulty in guiding the catheter into the left ICA. Results: Of the 29 aneurysms requiring guidance of a catheter into the left ICA, 9 aneurysms (31%) required conversion from TRA to TFA. More acute innominate-left common carotid artery (CCA) angle (P < 0.001) and older age (P = 0.015) were associated with a higher conversion rate to TFA. Receiver operating characteristic analysis revealed that optimal cutoff values for the innominate-left CCA angle and age to distinguish between nonconversion and conversion to TFA were 16° (area under the curve [AUC], 0.93; 95% confidence interval [CI], 0.83-1.00) and 74 years (AUC, 0.79; 95% CI, 0.61-0.96), respectively. Conclusion: A more acute innominate-left CCA angle and older age appear associated with difficulty delivering the guiding catheter into the left ICA for neurointervention through TRA.

Efficacy and safety of fetal posterior cerebral artery stented coil embolization for fetal posterior cerebral aneurysms.

PURPOSE: Aneurysms at the origin of the fetal posterior cerebral artery (fPCA) often show fPCA bifurcation from the aneurysm dome, impeding complete embolization and dense coil packing. The recanalization rate for fPCA aneurysms is therefore high. This study aimed to evaluate the efficacy and safety of stenting into fPCA for aneurysms with fPCA incorporated into the aneurysm to determine whether stenting can provide effective embolization results and prevent recanalization. METHODS: A total of 19 consecutive coil embolization procedures between February 2012 and June 2022 for unruptured fPCA aneurysms with fPCA branching from the dome of the aneurysm were divided into two groups: non-stenting (NS) group (n = 11) and stenting into fPCA (PS) group (n = 8). Data were obtained retrospectively and compared regarding embolization results, complications, and recanalization. RESULTS: Compared with the NS group, the PS group achieved significantly higher complete occlusion rate and packing density (p < 0.001, p = 0.01, respectively). No symptomatic complications were observed in the PS group. Both immediately after stenting and at the 1-year follow-up, no stent kinking, stenosis, occlusion, or malposition were observed in any patients in the PS group. During 1-year follow-up, the cumulative minor and major recanalization-free rate after coil embolization for fPCA aneurysms were significantly higher in the PS group compared with the NS group (p = 0.022, 0.0024, respectively). CONCLUSION: Stenting into fPCA for aneurysms with fPCA incorporated into the aneurysm achieved high-density complete embolization without increasing complications, and prevented recanalization. The fPCA stent-assisted coil embolization can offer an alternative treatment for fPCA aneurysms.

Risk factors for radial artery occlusion after neurointervention for unruptured intracranial aneurysm via transradial access.

PURPOSE: Neurointervention via transradial access (TRA) is less invasive than via transfemoral access. However, radial artery occlusion (RAO) may occur with TRA. The purpose of this study was to explore risk factors for RAO after coil embolization of unruptured intracranial aneurysms (UIAs) via TRA. METHODS: Forty-two consecutive patients who underwent coil embolization for UIAs via TRA between March 2021 and March 2022 and were available for angiographic evaluation 1 year after treatment were retrospectively reviewed. Multivariate logistic regression analysis was conducted to identify potential risk factors for RAO. RESULTS: Seventeen (40%) of the 42 patients showed RAO. Compared with the non-RAO group, radial artery size was significantly smaller (2.2 mm [interquartile range (IQR): 2.1, 2.4 mm] vs 2.6 mm [IQR: 2.5, 2.7 mm]; p = 0.001) and the incidence of radial artery spasm (RAS) was significantly higher in the RAO group. Multivariate analysis identified radial artery size (odds ratio [OR] 4.9 × 10-3, 95% confidence interval [CI] 6.4 × 10-5-0.38) and incidence of RAS (OR 14.8, 95%CI 2.1-105) as significant independent predictors of subsequent RAO. Based on receiver operating characteristic (ROC) curve analysis, the optimal cutoff for radial artery size was 2.5 mm (sensitivity, 82.4%; specificity, 76.0%; area under the ROC curve, 0.80 [95%CI 0.66-0.95]). CONCLUSION: Radial artery size and RAS represent reliable parameters for predicting RAO 1 year after coil embolization for UIA via TRA. Prophylaxis against RAS and limiting neurointervention via TRA to patients with radial artery larger than 2.5 mm in diameter may reduce the risk of postoperative RAO.

Compartment syndrome associated with vascular avulsion caused by transradial access in neurointervention for unruptured intracranial aneurysm: illustrative case.

BACKGROUND: Transradial access (TRA) has a lower risk of access-site complications than transfemoral access but can cause major puncture-site complications, including acute compartment syndrome (ACS). OBSERVATIONS: The authors report a case of ACS associated with radial artery avulsion after coil embolization via TRA for an unruptured intracranial aneurysm. An 83-year-old woman underwent embolization via TRA for an unruptured basilar tip aneurysm. Following embolization, strong resistance was felt during removal of the guiding sheath due to vasospasm of the radial artery. One hour after neurointervention via TRA, the patient complained of severe pain in the right forearm, with motor and sensory disturbance of the first 3 fingers. The patient was diagnosed with ACS causing diffuse swelling and tenderness over the entire right forearm due to elevated intracompartmental pressure. The patient was successfully treated by decompressive fasciotomy of the forearm and carpal tunnel release for neurolysis of the median nerve. LESSONS: TRA operators should be aware that radial artery spasm and the brachioradial artery pose a risk of vascular avulsion and resultant ACS and warrant precautionary measures. Prompt diagnosis and treatment are essential because ACS can be treated without the sequelae of motor or sensory disturbance if properly addressed.

Therapeutic efficacy and complications of radial versus femoral access in endovascular treatment of unruptured intracranial aneurysms.

PURPOSE: The transradial approach (TRA) in neuroendovascular treatment is known to have a lower risk of complications than the transfemoral approach (TFA). However, little research has focused on assessments of efficacy and risk of complications in the treatment of intracranial aneurysms. This study aimed to compare the efficacy and complications of TRA and TFA in coil embolization of unruptured intracranial aneurysms (UIAs) at our institution. METHODS: Consecutive patients who underwent endovascular surgery via TRA or TFA at a single institution from 1 April 2019, to 28 February 2022, were retrospectively analyzed. Patients were classified into TRA and TFA groups and assessed using propensity-adjusted analysis for outcomes including fluoroscopy time, volume embolization ratio (VER), and complications. RESULTS: A total of 163 consecutive UIAs were treated with coil embolization during the 35-months study period. The incidence of minor access site complications (ASCs) was significantly higher with TFA (20%, 25/126) than with TRA (2.7%, 1/37; p = 0.01). Propensity-adjusted analysis (matched for age, sex, aneurysm volume, embolization technique, and sheath size) revealed that TRA was associated with a lower risk of minor ASCs (odds ratio, 0.085; 95% confidence interval 0.0094-0.78; p = 0.029). However, TRA did not differ significantly from TFA with respect to fluoroscopy time, VER, major ASCs, and non-ASCs. CONCLUSIONS: Coil embolization for UIAs via TRA can reduce risk of minor ASCs without increasing the risk of non-ASCs compared with conventional TFA, and can achieve comparable results in term of efficacy and fluoroscopy time.

Thromboelastography 6s for assessment of platelet function during coil embolization of unruptured intracranial aneurysms.

OBJECTIVES: Methods for assessing platelet function in patients with neurovascular disease remain controversial and poorly studied. This study aimed to assess associations between thromboelastography 6s (TEG6s) measurements and postoperative ischemic complications in patients with unruptured intracranial aneurysms (UIAs) treated by coil embolization. METHODS: Eighty-four patients with UIAs taking a combined aspirin and clopidogrel protocol were retrospectively reviewed from January 2021 to May 2022. Blood samples were obtained for TEG6s to assess platelet function on the day of coil embolization. To identify acute ischemic complications, diffusion-weighted imaging (DWI) was performed within 24 h after coil embolization. Multivariate logistic regression analysis was conducted to identify potential risk factors for postoperative positive DWI (DWI (+)) lesions. RESULTS: Forty-three of the 84 patients (51%) with DWI (+) lesions were identified. Compared with patients without DWI (+) lesions, Adenosine diphosphate (ADP)-induced platelet-fibrin clot strength (MAADP) was significantly higher (53.6 mm [Interquartile range (IQR): 48.3-58.3 mm] vs 46.7 mm [IQR: 36.8-52.2 mm]; p=0.001) and ADP inhibition rate (ADP%) was significantly lower (19% [IQR: 11-31%] vs 31% [IQR: 21-44%]; p=0.001) in DWI (+) patients. Multivariate analysis identified MAADP, ADP%, and procedure time as significant independent predictors of subsequent DWI (+) lesions (odds ratios: 1.07, 0.96, and 1.02, respectively). Based on receiver operating characteristic curve analysis, MAADP >50.9 mm and ADP% <28.8% were associated with postoperative DWI (+) lesions in patients undergoing coil embolization for UIAs. CONCLUSIONS: MAADP and ADP% as assessed by TEG6s can offer reliable parameters to predict postoperative ischemic complications after coil embolization of UIAs. Lower MAADP values and higher ADP% may decrease the risk of postoperative ischemic complications.

A novel 3-Fr guiding sheath for transradial access in aneurysm embolization: Technical note.

Neurointervention via transradial access (TRA) is challenging when the radial artery is narrow. We performed aneurysm embolization via TRA using a novel 3-Fr guiding sheath (GS) (Axcelguide; Medikit, Tokyo, Japan) with an outer diameter of only 1.76 mm for patients with a radial artery of inner diameter less than 2 mm, and described the whole procedure and pitfalls as a technical note. Here, we present two patients with radial arteries less than 2 mm. One patient had a narrow neck intracranial aneurysm at the bifurcation of the left vertebral artery and posterior inferior cerebellar artery, which was embolized with the primary coiling technique. The other was a patient with a wide-necked extracranial aneurysm in the cavernous portion of the right internal carotid artery, which was embolized with the transcell technique with stent. We utilized a 3-Fr GS, distal access catheter, and a 0.0165-inch microcatheter for coil embolization. All aneurysms were completely occluded, without neurological or puncture site-related complications including subcutaneous hematoma, radial artery occlusion, and vasospasm. This report provides the first description of neurointervention using a 3-Fr GS. The 3-Fr GS contributed to successful completion of TRA aneurysm embolization without neurological or puncture site-related complications in patients with radial arteries narrower than 2 mm. The 3-Fr GS may be useful to accomplish aneurysmal embolization via TRA even in patients with a small radial artery.

Horizontal stenting via retrograde route for recurrent ruptured posterior communicating artery aneurysm after clipping: A case report and literature review.

Treatment of recurrent ruptured aneurysms incorporating a branch vessel arising from the dome is challenging. Here, we attempted horizontal stent-assisted coil embolization via a retrograde route from the contralateral internal carotid artery to treat a small ruptured posterior communicating artery aneurysm incorporating a fetal variant posterior cerebral artery after clipping.

Risk factors for recanalization of dense coil packing for unruptured cerebral aneurysms in endovascular coil embolization: Analysis of a single center's experience.

In coil embolization of cerebral aneurysms, inadequate packing is known to increase the probability of recanalization. Even tightly embolized aneurysms may be recanalized, but predictive factors for recanalization have not been fully investigated. This retrospective study aimed to identify risk factors for recanalization of treated aneurysms with a volume embolization ratio (VER) ≥ 25%. A total of 301 unruptured aneurysms in 248 patients who underwent coil embolization between March 2012 and January 2021 were analyzed. Cases involving dissecting aneurysm, intraluminal thrombosis, parent artery occlusion, intraoperative rupture, re-treatment, rupture the day after surgery, postoperative coil migration, and postoperative parent artery occlusion were excluded due to the inaccuracy of VER. A total of 105 aneurysms (34.9%) treated with VER ≥ 25% were extracted. Clinical features (age, sex, medical history, family history), anatomical features (shape, location, aneurysm size, inflow angle, and volume), procedural features (stent-assisted, Raymond-Roy occlusion classification [RROC] immediately after treatment, re-treatment rate), and follow-up period were compared between Recanalization and Non-recanalization groups. Predictors of recanalization were determined using logistic regression and receiver operating characteristic (ROC) curve analyses. Eleven aneurysms were recanalized. In multivariate analysis, RROC class 3 (odds ratio [OR] 11.0; 95% confidence interval [CI] 2.03-59.4) and aneurysm volume (OR 1.005; 95%CI 1.001-1.008) were independent predictors of recanalization. ROC curve analysis showed optimal cutoff values for aneurysm volume of 69.5 mm3 (sensitivity, 81.8%; specificity, 72.3%). In coil embolization of unruptured aneurysms that VER ≥ 25%, cases with RROC class 3 or high aneurysm volume may be associated with a higher risk of recanalization, and should be carefully followed-up.

Characteristics of Unruptured Intracranial Aneurysms with Delayed Rupture Following Coil Embolization: Case Series and Review of the Literature.

Objective: Long-term clinical outcomes including delayed rupture of unruptured intracranial aneurysms (UIAs) after coil embolization (CE) remain unclear. The purpose of this study was to evaluate the precise timing of re-treatment for recanalized UIAs before rupture. Methods: From February 2012 to June 2020, a total of 197 patients with 207 UIAs underwent CE in our institution and were followed up for more than 6 months. The follow-up period, as well as morphological changes from treatment to recanalization, regrowth, and rupture, was retrospectively analyzed. Delayed rupture was defined as a rupture that occurred more than 1 month after CE. Results: The average length of follow-up was 48.7 months. Three of 207 UIAs (1.45%) ruptured after CE. The aneurysm locations were the middle cerebral artery (MCA), anterior communicating artery (AcomA), and internal carotid artery-posterior communicating artery (ICA-Pcomm). The annual rupture rate after CE was 0.36%. Immediately after the first CE, treated aneurysms were graded according to the Modified Raymond-Roy Classification with class II for MCA aneurysms and class IIIb for AcomA and ICA-Pcomm aneurysms. The ICA-Pcomm aneurysm was treated with two additional CEs and was finally graded as class I. In all cases, DSA or MRA before aneurysm rupture showed recanalization and regrowth of aneurysms. The average periods from final embolization to regrowth and from regrowth to rupture were 54.3 months (±16.8) and 2.3 months (±0.9), respectively. Conclusion: UIAs with recanalization and regrowth after CE should undergo re-treatment as early as possible.

Delayed Tentorial Subdural Hematoma Caused by Traumatic Posterior Cerebral Artery Aneurysm: A Case Report and Literature Review.

BACKGROUND Subdural hematoma (SDH) caused by traumatic intracranial aneurysm (TICA) is rare. TICAs are known to rupture easily, resulting in a high morbidity and mortality rate. Therefore, accurate diagnosis and treatment are crucial for preserving life. We describe a case of delayed SDH in the setting of posterior cerebral artery (PCA) aneurysm. CASE REPORT A 42-year-old man presented with sustained head injury from a traffic accident, and was being followed-up conservatively for traumatic SDH and subarachnoid hemorrhage. Three weeks after the head trauma, the patient developed a sudden deterioration of mental status and disorientation. Computed tomography revealed de novo SDH at the cerebellar tentorium. Computed tomography angiography and magnetic resonance imaging demonstrated TICA in the PCA. The patient was diagnosed with SDH due to a ruptured PCA aneurysm at the quadrigeminal segment. To avoid SDH growth due to re-rupture of the aneurysm, parent artery occlusion was subsequently performed with no complications. The patient was discharged home 2 months after endovascular treatment, with moderate disability. Follow-up angiography 2 years after the operation showed no recanalization, and the patient had returned to work. CONCLUSIONS TICA in the PCA can cause tentorial SDH with or without the presence of subarachnoid hemorrhage. Routine cerebrovascular assessment is crucial for head trauma with hematoma adjacent to the cerebellar tentorium. Parent artery occlusion via an endovascular procedure is an alternative treatment for TICA in the PCA that is less invasive than other approaches.

Avoidance and Improvement in Visual Field Defect After Surgery for Metastatic Brain Tumors in the Parietal and the Occipital Lobe.

OBJECTIVE: Visual field defects occasionally occur secondary to tumors in the parietal and the occipital lobes. The aim of this study was to analyze the efficacy of improvement in hemianopsia after surgery for metastatic brain tumors involving or adjacent to the optic radiation (OR). METHODS: The study included 49 patients with brain metastasis in the parietal and occipital lobes in the present study. Preoperative and postoperative neurological assessments included visual field, Mini-Mental State Examination, and Karnofsky performance scale. RESULTS: Of 49 patients, 33 (67.3%) presented with preoperative homonymous hemianopsia. Of these 33 patients, the visual field was improved postoperatively in 17 patients (51.5%). In all patients regardless of preoperative hemianopsia, postoperative visual fields did not deteriorate. Tractography demonstrated that the OR was split by the tumor (n = 6) and fanning of fibers expanded along the lateral side of the tumor (n = 11). All tumors were removed via surgical access toward the medial side of the tumor. Gross total resection was achieved in most tumors in the group with visual improvement (n = 16/17; 94.1%). Improvement in the visual field was attributed to tumor location in the subcortical white matter, removal rate of the tumor, and higher postoperative Karnofsky performance scale score. CONCLUSIONS: The OR tended to deviate to the lateral side of the tumor in the parieto-occipital junction. The postoperative visual field improved even in cases of an occipital tumor. Based on the present study, total resection via an appropriate surgical route should be considered to preserve the OR, leading to improvement in the postoperative visual field.

Significantly high concentrations of vascular endothelial growth factor in chronic subdural hematoma with trabecular formation.

The underlying mechanism of chronic subdural hematoma (CSDH) after minor head injury is complex, probably due to mechanical injury of the arachnoid membrane, hematological coagulopathy, and pathological angiogenesis in the dura caused by inflammatory cytokines including vascular endothelial growth factor (VEGF). To confirm whether VEGF might be a reliable predictive biomarker for the natural history of CSDH, including progression and recurrence, we analyzed the correlation of VEGF concentration in the subdural fluid with CT findings and clinical features, including interval from minor head injury. Based on CT classification by hematoma density, the mean concentration of VEGF in hematoma fluid was found to be highest in the trabecular group, whereas the recurrence of CSDH was most frequent in the separated group in which VEGF concentration was low. There was a significant correlation between VEGF concentration and the CT classification. Furthermore, only in the trabecular group, a significant negative correlation between the VEGF concentration and interval from minor head injury to surgery was observed. These results suggest that VEGF concentration in the hematoma alone could not be a reliable predictive biomarker for the natural history of CSDH including its recurrence. Amongst the classified groups of CSDH, the trabecular group is likely to follow a different time course of VEGF concentration in the hematoma fluid compared to the other three groups.

Successful Endovascular Trapping for Symptomatic Thrombosed Giant Unruptured Aneurysms of the V1 and V2 Segments of the Vertebral Artery: Case Report and Literature Review.

A thrombosed giant aneurysm of the V1 and V2 segments of the vertebral artery (VA) is rare. Therefore, there is controversy regarding its optimal treatment. A case of a symptomatic giant VA aneurysm located in the V1 to V2 segments on the left treated successfully by endovascular trapping of the VA is reported. A 68-year-old woman presented with swelling in the left anterior neck. Computed tomography angiography (CTA) showed a giant aneurysm measuring 47 × 58 × 47 mm3 in the left neck. Ten days after her first visit, she presented with sudden onset of left anterior neck pain. Repeated CTA showed a partial thrombus in the aneurysm. Angiography showed two thrombosed giant aneurysms located in the V1 to V2 segments of the left VA. After endovascular trapping for the aneurysms, the anterior neck pain resolved and the aneurysm gradually shrank. This case demonstrates that endovascular surgery is better than open surgery because it is less invasive. When performing endovascular treatment, trapping will be an alternative strategy for a symptomatic giant thrombotic aneurysm of the V1 and V2 segments of the VA if the patient can tolerate ischemia.

Alteration of FOXM1 expression and macrophage polarization in refractory meningiomas during long-term follow-up.

Malignant progression of grade I meningioma with a long latency period is rare. We experienced grade II/III meningiomas with refractoriness and recurrence from grade I meningiomas through multiple surgeries. Three patients with atypical/anaplastic meningioma experienced long-latent recurrence after initial surgery for grade I (meningothelial) meningioma without following adjuvant radiotherapy were included in the present study. Histological findings of the initial tumors in all cases (case 1, 2, and 3) revealed meningothelial meningioma with 1%, 5%, and 0.1% MIB-1 positive cells, respectively. Surprisingly, magnetic resonance imaging (MRI) detected a recurrent tumor 2, 12, and 12 years after the initial operation, respectively. Case 1 was atypical meningioma after third recurrence, and case 2 and 3 were anaplastic meningioma after second and third recurrence, respectively. The patient in case 2 received adjuvant radiotherapy. In case 2, the tumor recurred intracranial and distant metastasis to the lung with huge substantial pleural effusion was detected. To investigate the pathogenesis of malignant progression from benign to malignant meningioma, CD163/CD68 expression by immunohistochemically and FOXM1 mRNA expression by RT-PCR were compared using surgical specimens from initial and recurrent tumors in all three patients. The ratio of CD163/CD68 positivity and FOXM1 mRNA expression were increased in recurrent tumors compared with matched initial tumors. CD163 and FOXM1 expression levels were induced even in recurrent grade I meningioma, suggesting that macrophage polarization and pro-mitotic transcriptional factor might be associated with clinical behavior of meningioma and be useful as a prediction marker for malignant progression. Careful long-term follow-up is important for early diagnosis of malignant progression in meningiomas, even if grade I meningioma is completely resected. Development of a multidisciplinary approach including radiation and novel molecular targeted therapy is expected for recurrent and malignant meningiomas.

[Technical "Tips" for Epidural Tenting Using DuraGen® for Surgical Management of Large Dural Defects:A Technical Note].

DuraGen®, an absorbable, engineered collagen-based artificial graft was introduced in Japan in September 2019 for cranial, transsphenoidal, and spinal surgeries. In addition to its efficacy and safety profile, owing to sutureless dural repair, DuraGen® is widely accepted by neurosurgeons. Direct tenting with DuraGen® is occasionally required in patients with large dural defects, particularly in cases of tumors adherent to the dura. To overcome this limitation, we introduced a surgical technique for epidural tenting using DuraGen®. A 78-year-old man with a history of alexia underwent craniotomy for resection of a left temporal lobe metastatic tumor. We completely removed the recurrent tumor, which was strongly adherent to the dura in the middle cranial fossa. A layer of DuraGen® was used as a subdural underlay beneath the autologous dura to close the wide dural defect. To avoid postoperative epidural fluid collection, we retracted the DuraGen® from the epidural aspect and interposed several pieces of muscle, which were sutured on the subdural aspect to ensure that the muscle pieces securely plugged the dural defect. We placed an additional overlay of DuraGen® along the autologous dura. The patient's postoperative course was uneventful without cerebrospinal fluid leakage, tension pneumocephalus, or wound infection. Reoperations for tumor resection, particularly surgical procedures for refractory meningiomas and malignant tumors cause increasing fragility and wide defects of the dura. DuraGen® placement enables sutureless closure and is less time-consuming. Our technique of epidural direct tenting with DuraGen® using muscle pieces sutured on the subdural aspect could be useful in patients with significantly large dural defects and can prevent postoperative epidural fluid collection to ensure complete dural sealing.

IgG4-Related Disease in the Frontal Convexity Concomitant with Smoldering Multiple Myeloma: A Case Report and Review of the Literature Regarding Therapeutic Implications.

BACKGROUND: We have reported an extremely rare case of a frontal convexity tumor diagnosed as IgG4-related disease (IgG4-RD) with unique neuroradiological images. CASE DESCRIPTION: A 64-year-old man with a history of monoclonal gammopathy of undetermined significance and conservative treatment had presented with a left facial spasm. Computed tomography showed a high-density round tumor with perifocal edema in the right frontal convexity. Magnetic resonance imaging demonstrated unique findings, including low signal intensity on T1- and T2-weighted, fluid-attenuated inversion recovery, and diffusion-weighted images, with slight gadolinium enhancement. The tumor was totally removed via right frontal craniotomy. It had been located in the subdural space, was not adherent to the dura, and was less vascular than meningiomas. Histological investigation demonstrated plasma cells that were strongly positive for IgG4 and contained κ and λ light chains at a ratio of 1.5:1. The serum IgG4 level was elevated. The tumor met the diagnostic criteria for IgG4-RD. The patient was followed up for 3 years during postoperative adjuvant steroid therapy. The steroid therapy was discontinued, and during the next 4 years, neither tumor recurrence nor symptoms were observed. CONCLUSION: Intracranial IgG4-RD with smoldering monoclonal gammopathy of undetermined significance is extremely rare. We reviewed the differential diagnosis of plasma cell granuloma and plasmacytoma, therapeutic implications, and clinical outcomes. Complete resection of a conspicuous and solitary IgG4-RD lesion in the frontal convexity is simple and could provide a cure with less-aggressive adjuvant therapy.

Rapid Recurrence and Anaplastic Transformation of a Pilocytic Astrocytoma in an Elderly Patient: Case Report and Review of the Literature.

BACKGROUND: Rapid recurrence of a pilocytic astrocytoma with anaplastic transformation is extremely rare. The case of an elderly patient with a cerebellar pilocytic astrocytoma with anaplastic transformation during short-term follow-up is reported. CASE DESCRIPTION: An 83-year-old woman presented initially with dizziness and a gait deviation to the right. Magnetic resonance imaging demonstrated a homogeneously enhanced mass in the right cerebellar hemisphere, and the tumor was subtotally removed by right suboccipital craniotomy. Histologic examination showed that the tumor cells contained eosinophilic cytoplasm and spindle-shaped processes with Rosenthal fibers and eosinophilic granular bodies, diagnosed as a typical pilocytic astrocytoma (PA). The MIB-1 index was <1%. The patient did not receive postoperative adjuvant radiation and chemotherapy. Two months after surgery, magnetic resonance imaging showed growth of the residual tumor adjacent to the fourth ventricle, causing obstructive hydrocephalus. She underwent surgery again, and the tumor was totally removed. Histologic findings showed mitotic cells and increased cellularity compared with the primary tumor, which was compatible with anaplastic transformation of PA with a MIB-1 index of 50%. Postoperatively, she was observed with best supportive care without postoperative adjuvant therapy. Nine months after the second operation, she died due to tonsillar herniation and obstructive hydrocephalus caused by a recurrent tumor. An autopsy was performed. CONCLUSIONS: It is extremely rare, as in the present case, that a cerebellar PA in an elderly patient recurs rapidly with anaplastic transformation, despite deferred postoperative adjuvant therapy including radiation and chemotherapy. A novel molecular-targeted therapy is needed for anaplastic PA showing aggressive biological behavior.