Incidence of and risk factors for chronic subdural hematoma after endoscopic endonasal surgery: quantitative analysis of pneumocephalus.

OBJECTIVE: Chronic subdural hematoma (CSDH) is known to occur after endoscopic endonasal surgery (EES); however, the detailed clinical picture remains unclear. In this study, the authors aimed to examine the incidence of and risk factors for post-EES CSDH, with a focus on the quantitative evaluation of postoperative pneumocephalus. METHODS: The authors retrospectively collected data on consecutive patients who, between November 2016 and December 2022, had undergone EES during which intraoperative cerebrospinal fluid (CSF) leakage occurred. Using CT images obtained immediately after surgery (CT0), the authors measured the extent of pneumocephalus in detail. The locations of pneumocephalus were divided into two groups: remote and local. Remote pneumocephalus was further subdivided into convexity and ventricular. The incidence of post-EES CSDH was calculated, and its risk factors were analyzed. RESULTS: Among the 159 EES patients included in the study, Esposito grade 1, 2, and 3 intraoperative CSF leakage was confirmed in 22 (14%), 27 (17%), and 110 (69%) patients, respectively. CSDH occurred in 6 patients (3.8%). One patient (0.6%) required unilateral burr hole surgery, whereas the hematomas spontaneously disappeared in the others. All CSDHs occurred in patients with Esposito grade 3 CSF leakage and convexity pneumocephalus on CT0. In the multivariate analysis of 149 sides with convexity pneumocephalus on CT0, the product of the diameter and the thickness of convexity pneumocephalus on CT0 was significantly associated with subsequent CSDH (OR 1.21, 95% CI 1.06-1.38, p = 0.004). Using a cutoff value of 10 cm2, CSDH development could be predicted with a sensitivity of 0.82 and specificity of 0.74. CONCLUSIONS: The incidence of post-EES CSDH is acceptably low, and surgery is rarely required. Patients with extensive convexity pneumocephalus on immediate postoperative CT are prone to develop CSDH and thus should be carefully monitored.

Safety evaluation of sinus patency after stereotactic radiosurgery for transverse-sigmoid sinus dural arteriovenous fistulas: implications of treatment options for patients with Borden type I fistulas.

OBJECTIVE: This study aimed to assess the efficacy and safety of stereotactic radiosurgery (SRS) in treating transverse-sigmoid sinus dural arteriovenous fistulas (TSS DAVFs), and to investigate post-SRS sinus patency, focusing on the risk factors associated with treated sinus occlusion. METHODS: Data from 34 patients treated with SRS between January 2006 and April 2023 were analyzed. Detailed angioarchitecture was confirmed using digital subtraction angiography before SRS. Angiography of the ipsilateral internal carotid artery and vertebral artery was performed to evaluate whether the involved side of the TSS was used for normal venous drainage. TSS stenosis was defined as sinus diameter < 50% of the normal proximal diameter. DAVF shunt obliteration, TSS occlusion, neurological status, and adverse events were also evaluated. RESULTS: Of the 34 patients, 21 had Borden type I and 14 had Borden type II DAVFs. The median age at SRS was 64 years (interquartile range 54-71 years), and the follow-up period was 31 months (interquartile range 15-94 months). Complete shunt obliteration was achieved in 24 (70.6%) patients. The cumulative 2-, 3-, and 5-year shunt obliteration rates were 49.6%, 71.2%, and 86.0%, respectively. Borden type I had higher obliteration rates (60.5%, 83.1%, and 94.4%, respectively) than Borden type II (41.7%, 51.4%, and 75.7%, respectively; p = 0.034). TSS occlusion occurred in 5 patients (14.7%). The cumulative 1-, 5-, and 10-year TSS occlusion rates were 2.9%, 8.3%, and 23.6%, respectively, across the entire cohort. All occlusions occurred exclusively in the sinuses that were not used for normal venous drainage. Cox proportional analyses revealed that TSS stenosis and the sinus not being used for normal venous drainage were significantly associated with a greater risk of TSS occlusion after SRS (HR 9.44, 95% CI 1.01-77.13; p = 0.049). CONCLUSIONS: SRS is effective and safe for TSS DAVF and results in favorable shunt obliteration, symptom improvement, and low complication rates. TSS occlusion after SRS is asymptomatic and is limited to sinuses that are not used for normal venous drainage.

Role of stereotactic radiosurgery for recurrent skull base acinic cell carcinoma: illustrative case.

BACKGROUND: Acinic cell carcinomas (AcCCs), rare malignancies of the salivary glands, often recur and metastasize, particularly in the skull base. Conventional radical resection can be invasive for skull base AcCCs adjacent to cranial nerves and major vasculature, and the effectiveness of stereotactic radiosurgery (SRS) as an alternative is not well established. OBSERVATIONS: This case report details the application of SRS for recurrent skull base AcCCs. A 71-year-old male with a history of resection for a right mandibular AcCC 23 years earlier experienced tumor recurrence involving the right cavernous sinus and nasal cavity. He underwent endoscopic transnasal surgery followed by SRS targeting different tumor locations-the cavernous sinus to the pterygopalatine fossa, maxillary sinus, and clivus-each with a prescribed dose of 20 Gy to the 40% to 50% isodose line. After the first skull base metastasis, additional sessions of localized SRS after endoscopic surgery led to a 12-year survival without sequela. LESSONS: This is a report indicating that SRS for skull base AcCCs can achieve favorable local control, functional preservation, and long-term survival. SRS may be suitable for skull base AcCC given the lesion's tendency toward multiple local recurrences. Further investigation is needed to validate the treatment's efficacy.

Long-term geometric quality assurance of radiation focal point and cone-beam computed tomography for Gamma Knife radiosurgery system.

To investigate the geometric accuracy of the radiation focal point (RFP) and cone-beam computed tomography (CBCT) over long-term periods for the ICON Leksell Gamma Knife radiosurgery system. This phantom study utilized the ICON quality assurance tool plus, and the phantom was manually set on the patient position system before the implementation of treatment for patients. The deviation of the RFP position from the unit center point (UCP) and the positions of the four ball bearings (BBs) in the CBCT from the reference position were automatically analyzed. During 544 days, a total of 269 analyses were performed on different days. The mean ± standard deviation (SD) of the deviation between measured RFP and UCP was 0.01 ± 0.03, 0.01 ± 0.03, and -0.01 ± 0.01 mm in the X, Y, and Z directions, respectively. The deviations with offset values after the cobalt-60 source replacement (0.00 ± 0.03, -0.01 ± 0.01, and -0.01 ± 0.01 mm in the X, Y, and Z directions, respectively) were significantly (p = 0.001) smaller than those before the replacement (0.02 ± 0.03, 0.02 ± 0.01, and -0.02 ± 0.01 mm in the X, Y, and Z directions, respectively). The overall mean ± SD of four BBs was -0.03 ± 0.03, -0.01 ± 0.05, and 0.01 ± 0.03 mm in the X, Y, and Z directions, respectively. Geometric positional accuracy was ensured to be within 0.1 mm on most days over a long-term period of more than 500 days.

Ki-67 labeling index predicts tumor progression patterns and survival in patients with atypical meningiomas following stereotactic radiosurgery.

PURPOSE: This study investigated whether Ki-67 labeling index (LI) correlated with clinical outcomes after SRS for atypical meningiomas. METHODS: This retrospective study examined 39 patients with atypical meningiomas who underwent SRS over a 10-year study period. Ki-67 LI was categorized into 3 groups: low (< 5%), intermediate (5%-10%), and high (> 10%). Local tumor control rates (LCRs), progression-free rates (PFRs), disease-specific survival (DSS) rates, and adverse radiation-induced events (AREs) were evaluated. RESULTS: The median follow-up periods were 26 months. SRS was performed at a median prescription dose of 18 Gy for tumors with a median Ki-67 LI of 9.6%. The 3-year LCRs were 100%, 74%, and 25% in the low, intermediate, and high LI groups, respectively (p = 0.011). The 3-year PFRs were 100%, 40%, and 0% in the low, intermediate, and high LI groups (p = 0.003). The 5-year DSS rates were 100%, 89%, and 50% in the low, intermediate, and high LI groups (p = 0.019). Multivariable Cox proportional hazard analysis showed a significant correlation of high LI with lower LCR (hazard ratio [HR], 3.92; 95% confidence interval [CI] 1.18-13.04, p = 0.026), lower PFR (HR 3.80; 95% CI 1.46-9.88, p = 0.006), and shorter DSS (HR 6.55; 95% CI 1.19-35.95, p = 0.031) compared with intermediate LI. The ARE rates were minimal (8%) in the entire group. CONCLUSION: Patients with high Ki-67 LI showed significantly more tumor progression and tumor-related death. Ki-67 LI might offer valuable predictive insights for the post-SRS management of atypical meningiomas.

Trans-Distal Radial Artery Carotid Revascularization with Forearm Flow Reversal: An Alternative Option of CAS in the TCAR Era.

BACKGROUND: Transcarotid artery revascularization (TCAR) has emerged as an alternative to carotid artery stenting (CAS). TCAR demonstrated its superiority by avoiding femoral artery puncture and establishing proximal protection without crossing the stenotic lesion. In the TCAR era, we focused on the possibility of a trans-distal radial approach (DRA). A balloon-guide catheter was navigated via DRA to establish proximal protection before lesion crossing. The forearm subcutaneous vein was used as the flow-reversal circuit. METHODS: Six internal carotid artery stenosis patients underwent CAS using "the forearm flow reversal technique." Every procedure was performed under continuous flow reversal from the common carotid artery to the forearm cephalic vein. RESULTS: Successful revascularization was achieved without ischemic or access-site complications. The distal radial artery was patent at discharge in all cases. CONCLUSIONS: Trans-distal radial CAS with forearm flow reversal is a feasible and less invasive technical option.

Long-term outcomes of stereotactic radiosurgery for intracranial schwannoma in neurofibromatosis type 2: a genetic analysis perspective.

PURPOSE: Neurofibromatosis type 2 (NF2) is intractable because of multiple tumors involving the nervous system and is clinically diverse and genotype-dependent. Stereotactic radiosurgery (SRS) for NF2-associated schwannomas remains controversial. We aimed to investigate the association between radiosurgical outcomes and mutation types in NF2-associated schwannomas. METHODS: This single-institute retrospective study included consecutive NF2 patients with intracranial schwannomas treated with SRS. The patients' types of germline mutations ("Truncating," "Large deletion," "Splice site," "Missense," and "Mosaic") and Halliday's genetic severity scores were examined, and the associations with progression-free rate (PFR) and overall survival (OS) were analyzed. RESULTS: The study enrolled 14 patients with NF2 with 22 associated intracranial schwannomas (median follow-up, 102 months).　The PFRs in the entire cohort were 95% at 5 years and 90% at 10-20 years. The PFRs tended to be worse in patients with truncating mutation exons 2-13 than in those with other mutation types (91% at 5 years and 82% at 10-20 years vs. 100% at 10-20 years, P = 0.140). The OSs were 89% for patients aged 40 years and 74% for those aged 60 years in the entire cohort and significantly lower in genetic severity group 3 than in the other groups (100% vs. 50% for those aged 35 years; P = 0.016). CONCLUSION: SRS achieved excellent PFR for NF2-associated intracranial schwannomas in the mild (group 2A) and moderate (group 2B) groups. SRS necessitates careful consideration for the severe group (group 3), especially in cases with NF2 truncating mutation exons 2-13.

Impact of ventriculo-cisternal irrigation on prevention of delayed cerebral infarction in aneurysmal subarachnoid hemorrhage: a single-center retrospective study and literature review.

OBJECTIVE: The aim of this study was to evaluate the effectiveness of ventriculo-cisternal irrigation (VCI) in preventing vasospasms and delayed cerebral infarction (DCI) by washing out subarachnoid clots earlier after aneurysm surgery. METHODS: We retrospectively identified 340 subarachnoid hemorrhage (SAH) patients with ruptured intracranial aneurysms treated with postoperative VCI at our institution between December 2010 and January 2020. As VCI therapy, a ventricular drain/cisternal drain was placed during aneurysm surgery, and lactated Ringer's solution was used for irrigation until day 4 of SAH, followed by intracranial pressure control at 5-10 cmH2O until day 14. RESULTS: The median age was 65 years (interquartile range 52-75), with 236 female patients (69%). The World Federation of Neurosurgical Societies grade distribution was as follows: grade I or II, 175 patients (51%); grade III or IV, 84 (25%); and grade V, 81 (24%). With VCI management in all patients, total vasospasm occurred in 162 patients (48%), although the DCI incidence was low (23 patients [6.8%]). Major drainage-related complications were observed in five patients (1.5%). Early surgery, performed on SAH day 0 or 1, was identified as a preventive factor against DCI occurrence (odds ratio (OR) 0.21, 95% confidence interval (CI) 0.07-0.67; P = 0.008), while additional surgery (4.76, 1.62-13.98; P = 0.005) and dyslipidemia (3.27, 1.24-8.63; P = 0.017) were associated with DCI occurrence. CONCLUSION: Managing vasospasms with VCI after SAH is considered a safe and effective method to prevent DCI. Early surgery after SAH may be associated with a decreased risk of DCI with VCI therapy.

Double-catheter technique for the embolization of recurrent cerebral aneurysms: A single-center experience.

Background: Recurrent cerebral aneurysms have complex shapes and are often technically challenging to treat with a single microcatheter. This study evaluates the clinical characteristics and treatment outcomes of patients who received double-catheter coil embolization for recurrent cerebral aneurysms. Methods: Patients who underwent double-catheter coil embolization at our institution between April 2011 and March 2022 for recurrent aneurysms were included in the study. Baseline characteristics, course to recurrence, details of the procedures, and outcomes after endovascular treatment were retrospectively analyzed based on past medical records. Results: Eight patients with recurrent aneurysms were treated with the double-catheter technique. One patient had a subarachnoid hemorrhage due to a rupture of a recurrent aneurysm and the others had radiological recurrence during follow-up. The initial treatment for the aneurysm was clipping in one case and coiling in seven cases. All the aneurysms were located at bifurcation sites. During retreatment, balloon remodeling technique was used in five cases. Angiographic features immediately after the treatment included complete occlusion in one case, neck remnant in three cases, and dome filling in four cases. There were no procedure-related severe complications, besides preexisting oculomotor nerve palsy due to the mass effect of the aneurysm worsened in one patient. The mean follow-up period after retreatment was 4.3 years. There was one case of recurrence after retreatment in which additional endovascular coiling was necessary. Conclusion: This study demonstrated that the double-catheter technique could be a safe and useful treatment option for patients with recurrent aneurysms at bifurcation sites.

Cerebrovascular Events During Treatment for Systemic Malignant Tumors in Patients with Moyamoya Disease.

OBJECTIVE: With the increasing incidence of malignancies, the importance of cancer-associated stroke is emphasized. Although moyamoya disease is a leading cause of stroke, no reports have documented cancer-associated stroke in patients with this condition. We aimed to investigate cerebrovascular events during malignancy treatments in patients with moyamoya disease. METHODS: A total of 405 patients with moyamoya disease who visited our hospital between January 2000 and March 2022 were retrospectively examined. We evaluated the management of moyamoya disease, presence of the ring finger protein 213 p.Arg4810Lys variant, treatments for malignant tumors, presence of cerebrovascular events during treatment, and follow-up periods and outcomes. RESULTS: Among the 405 patients, 17 patients with moyamoya disease (4.2%) were diagnosed with malignancies. Among patients aged 60 years and over, 7 out of 67 (10.4%) had malignancies. Of the 17 patients, 11 (64.7%) were symptomatic, and 7 (41.2%) had revascularization surgery. 9 patients were treated with oral antiplatelet drugs. There was no significant difference between the groups with and without malignancy regarding the presence of the ring finger protein 213 p.Arg4810Lys variant (80.0% vs. 62.7%, P = 0.33). All patients underwent surgical treatment, and 7 (41.2%) received chemotherapy. One death due to tumor progression was reported. No cerebrovascular event was observed during malignancy treatments and follow-up periods, which had a mean duration of 6 years. CONCLUSIONS: In our cohort, malignancy treatments in patients with moyamoya disease were safely conducted without cerebrovascular events. However, it is advisable to avoid hypotension, dehydration, hyperventilation, and long-term discontinuation of antiplatelet drugs during the treatment of malignant tumors.

Long-Term Outcomes of Stereotactic Radiosurgery for Postoperative World Health Organization Grade I Skull Base Meningioma: Utility of Ki-67 Labeling Index as a Prognostic Indicator.

BACKGROUND: Gross total resection, without causing neurological deficits, is challenging in skull base meningioma (SBM). Therefore, stereotactic radiosurgery (SRS) is an important approach for SBMs; however, it is difficult to predict the long-term prognosis. OBJECTIVE: To identify the predictive factors for tumor progression after SRS for World Health Organization (WHO) grade I SBMs, focusing on the Ki-67 labeling index (LI). METHODS: In this single-center retrospective study, factors affecting progression-free survival rates (PFSs) and neurological outcomes in patients undergoing SRS for postoperative SBMs were evaluated. Based on the Ki-67 LI, patients were classified into 3 groups: low (<4%), intermediate (4%-6%), and high LI (>6%). RESULTS: In the 112 patients enrolled, the cumulative 5- and 10-year PFSs were 93% and 83%, respectively. The PFSs were significantly higher in the low LI group (95% at 10 years) compared with the other groups (intermediate LI, 60% at 10 years, P = .007; high LI, 20% at 10 years, P = .001). Multivariable Cox proportional hazard analysis demonstrated that the Ki-67 LI was significantly associated with the PFSs (low vs intermediate LI; hazard ratio, 6.00; 95% CI, 1.41-25.54; P = .015; low vs high LI; hazard ratio, 31.90; 95% CI, 5.59-181.77; P = .001). CONCLUSION: Ki-67 LI may be a useful predictor of long-term prognosis in SRS for postoperative WHO grade I SBM. SRS provides excellent long- and mid-term PFSs in SBMs with Ki-67 LIs <4% or 4% to 6%, with a low risk of radiation-induced adverse events.

RNF213 p.Arg4810Lys Wild Type is Associated with De Novo Hemorrhage in Asymptomatic Hemispheres with Moyamoya Disease.

Clinical implications of RNF213 genetic variants, other than p.Arg4810Lys, in moyamoya disease (MMD), remain unclear. This study aimed to investigate the association of RNF213 variants with clinical phenotypes in MMD. This retrospective cohort study collected data regarding the clinical characteristics of 139 patients with MMD and evaluated the angioarchitectures of 253 hemispheres using digital subtraction angiography at diagnosis. All RNF213 exons were sequenced, and the associations of clinical characteristics and angiographical findings with p.Arg4810Lys, p.Ala4399Thr, and other rare variants (RVs) were examined. Among 139 patients, 100 (71.9%) had p.Arg4810Lys heterozygote (GA) and 39 (28.1%) had the wild type (GG). Fourteen RVs were identified and detetcted in 15/139 (10.8%) patients, and p.Ala4399Thr was detected in 17/139 (12.2%) patients. Hemispheres with GG and p.Ala4399Thr presented with significantly less ischemic events and more hemorrhagic events at diagnosis (p = 0.001 and p = 0.028, respectively). In asymptomatic hemispheres, those with GG were more susceptible to de novo hemorrhage than those with GA (adjusted hazard ratio [aHR] 5.36) with an increased risk when accompanied by p.Ala4399Thr or RVs (aHR 15.22 and 16.60, respectively). Within the choroidal anastomosis-positive hemispheres, GG exhibited a higher incidence of de novo hemorrhage than GA (p = 0.004). The GG of p. Arg4810Lys was a risk factor for de novo hemorrhage in asymptomatic MMD hemispheres. This risk increased with certain other variants and is observed in choroidal anastomosis-positive hemispheres. A comprehensive evaluation of RNF213 variants and angioarchitectures is essential for predicting the phenotype of asymptomatic hemispheres in MMD.

Stereotactic radiosurgery for recurrent skull base polymorphous adenocarcinoma invading the cavernous sinus: illustrative case.

BAKGROUND: Polymorphous adenocarcinomas (PACs) are rare tumors arising from the salivary glands. Radical resection and postoperative radiotherapy are the mainstays of treatment. However, complete tumor resection is not always achievable when the tumor invades the skull base. Stereotactic radiosurgery (SRS) could be a less invasive alternative for treating skull base PACs. OBSERVATIONS: A 70-year-old male with a history of surgery for a right palatine PAC presented with right visual impairment, diplopia, and ptosis. Imaging studies revealed tumor recurrence invading the right cavernous sinus (CS). SRS using a gamma knife was performed for this recurrence, prescribing a marginal dose of 18 Gy at a 50% isodose line. Five months after SRS, his symptoms were relieved, and the tumor was well-controlled for 55 months without any adverse events. LESSONS: To the best of the authors' knowledge, this is the world's first case of recurrent skull base PAC invading the CS that was successfully treated with salvage SRS. Thus, SRS may be an applicable treatment option for skull base PACs.

Controversies and challenges of coil embolization for intracranial aneurysm in a continuous-flow LVAD implanted patient: A case report.

Background: Continuous-flow left ventricular assist device (CF-LVAD) technology has rapidly developed to support the failing heart refractory to standard medical treatments. Although the expected prognosis has improved dramatically, ischemic and hemorrhagic strokes are possible complications and the leading causes of death in the CF-LVAD population. Case Description: We encountered a case of an unruptured large internal carotid aneurysm in a patient with a CF-LVAD. Following a detailed discussion of his expected prognosis, the risk of aneurysm rupture, and the inherited risk of aneurysm treatment, coil embolization was performed without adverse events. The patient remained recurrence-free for 2-year postoperatively. Conclusion: This report illustrates the feasibility of coil embolization in a CF-LVAD recipient and emphasizes the necessity of vigilant consideration of whether to intervene in an intracranial aneurysm after CF-LVAD implantation. We confronted several challenges during the treatment: optimal endovascular technique, management of antithrombotic drugs, safe arterial access, desirable perioperative imaging modalities, and prevention of ischemic complications. This study aimed to share this experience.

Primary Stereotactic Radiosurgery Provides Favorable Tumor Control for Intraventricular Meningioma: A Retrospective Analysis.

The surgical resection of intraventricular meningiomas (IVMs) remains challenging because of their anatomically deep locations and proximity to vital structures, resulting in non-negligible morbidity and mortality rates. Stereotactic radiosurgery (SRS) is a safe and effective treatment option, providing durable tumor control for benign brain tumors, but its outcomes for IVMs have rarely been reported. Therefore, the goal of the present study was to evaluate the SRS outcomes for IVMs at our institution. This retrospective observational study included 11 patients with 12 IVMs with a median follow-up period of 52 months (range, 3-353 months) treated with SRS using the Leksell Gamma Knife. Nine (75%) tumors were located in the trigone of the lateral ventricle, two (17%) in the body of the lateral ventricle, and one (8%) in the third ventricle. Tumor control was achieved in all cases, and seven (55%) decreased in size. Post-SRS perifocal edema was observed in four (37%; three asymptomatic and one symptomatic but transient) patients, all of which were resolved by the last follow-up. SRS appears to provide safe and excellent tumor control for IVMs. A longer follow-up with a larger number of cases is desired for a more solid conclusion.

Clinical and Genetic Characteristics of Patients with Moyamoya Disease who Experienced Both Ischemic and Hemorrhagic Events.

OBJECTIVE: Cerebrovascular events in moyamoya disease are mainly classified into ischemic or hemorrhagic onset. It is rare for one patient to develop both ischemia and hemorrhage in moyamoya disease; detailed clinical course and genetic characteristics of such patients have not been elucidated. We aimed to clarify the clinical features of patients with both ischemic and hemorrhagic cerebrovascular events. METHODS: We analyzed the background factors, radiological features, and genotype of ring finger protein 213 c.14429 G > A (p.Arg4810Lys) of patients with moyamoya disease who visited our hospital between 1996 and 2020, and experienced both ischemic and hemorrhagic cerebrovascular events. Additionally, we analyzed factors that caused subsequent hemorrhage in adult-onset ischemic moyamoya disease. RESULTS: Of 262 patients, 12 presented with both ischemia and hemorrhage, of which, 4 exhibited pediatric onset and 8 had adult onset. In pediatric-onset subjects, ischemia was the initial event in all cases. Hemorrhagic events occurred at a median of 24.7 years postoperatively in patients who had undergone bypass surgery. In adult-onset subjects, ischemia preceded hemorrhage in 7 patients. In males, the interval to subsequent hemorrhage was significantly shorter for adult-onset ischemic moyamoya disease, and the hazard ratio for hemorrhagic events was 5.45. The ring finger protein 213 p.Arg4810Lys heterozygous variant was present in 9 patients. CONCLUSIONS: A majority of patients with moyamoya disease with both ischemia and hemorrhage experience an ischemic event first. Patients who developed ischemia in childhood may develop subsequent hemorrhage in approximately 20-25 years after bypass surgery. Male sex is a risk factor for a subsequent hemorrhagic event in adult-onset ischemic moyamoya disease.

Genetics of brain arteriovenous malformations and cerebral cavernous malformations.

Cerebrovascular malformations comprise abnormal development of cerebral vasculature. They can result in hemorrhagic stroke due to rupture of lesions as well as seizures and neurological defects. The most common forms of cerebrovascular malformations are brain arteriovenous malformations (bAVMs) and cerebral cavernous malformations (CCMs). They occur in both sporadic and inherited forms. Rapidly evolving molecular genetic methodologies have helped to identify causative or associated genes involved in genesis of bAVMs and CCMs. In this review, we highlight the current knowledge regarding the genetic basis of these malformations.

Stereotactic radiosurgery for recurrent pleomorphic adenoma of the lacrimal gland: a case report.

Lacrimal gland pleomorphic adenomas (LGPAs) are common, benign, and intraorbital tumours that cause exophthalmos, ptosis, and visual disturbances. The curative treatment for LGPAs is gross total resection, and radiotherapy is considered adjunctive for recurrence or an alternative for inoperable LGPAs. Stereotactic radiosurgery (SRS) can be used for precise delivery of high radiation doses to the tumour, crucial in the treatment of intra-and extracranial neoplasms. Here, we present a 95-year-old woman who had a rapidly growing, recurrent LGPA and was successfully treated with SRS. The tumour was controlled without any adverse events over 21 months following SRS. SRS is a potential alternative treatment for recurrent LGPA.

Prognosis of Rotational Angiography-Based Stereotactic Radiosurgery for Dural Arteriovenous Fistulas: A Retrospective Analysis.

BACKGROUND: Cerebral dural arteriovenous fistulas (DAVFs) are intracranial vascular malformations with fine, abnormal vascular architecture. High-resolution vascular imaging is vital for their visualization. Currently, rotational angiography (RA) provides the finest 3-dimensional visualization of the arteriovenous shunt with high spatial resolution; however, the efficacies of the integration of RA have never been studied in stereotactic radiosurgery (SRS) for DAVFs until now. Since 2015, our institution has integrated RA into SRS (RA-SRS) to provide more conformal planning, thereby decreasing overtreatment and undertreatment. OBJECTIVE: To analyze the outcomes of RA-SRS for DAVFs. METHODS: We retrospectively analyzed the outcomes of 51 patients with DAVFs and compared those of 20 DAVFs treated with RA-SRS with those of 31 DAVFs treated with conventional SRS (c-SRS). RESULTS: The time to obliteration was shorter in the RA-SRS group (median, 15 months vs 26 months [cumulative rate, 77% vs 33% at 2 years, 77% vs 64% at 4 years]; P = .015). Multivariate Cox proportional hazards analysis demonstrated that RA-SRS (hazard ratio 2.39, 95% CI 1.13-5.05; P = .022) and the absence of cortical venous reflux (hazard ratio 2.12, 95% CI 1.06-4.25; P = .034) were significantly associated with obliteration. The cumulative 5-year post-SRS stroke-free survival rates were 95% and 97% in the RA-SRS and c-SRS groups, respectively ( P = .615). Neurological improvement tended to occur earlier in the RA-SRS group than in the c-SRS group (median time to improvement, 5 months vs 20 months, log-rank test; P = .077). CONCLUSION: RA-based SRS may facilitate earlier fistula obliteration and may contribute to early neurological improvement.