Endovascular management of intracranial carotid blowout syndrome in patients with head and neck cancer.

BACKGROUND: Carotid blowout syndrome is a serious complication of head and neck cancer (HNC) that may involve the intracranial or extracranial internal carotid artery (ICA). Although parent artery occlusion (PAO) is the major endovascular treatment for intracranial carotid blowout syndrome (iCBS), the efficacy of using a balloon-expandable coronary stent-graft (BES) remains unclear. METHODS: This was a quasi-randomized trial, prospective study that included patients with iCBS treated by BES or PAO between 2018 and 2024. Patients were allocated to either group based on the last digit of their chart number; even numbers went to the BES group and odd numbers to the PAO group. The inclusion criteria of iCBS included the pathological process of CBS involving petrous and/or cavernous ICA detected by both imaging and clinical features. The primary outcome was defined as rebleeding events after intervention. The secondary outcome was defined as neurological complication after intervention. RESULTS: Fifty-nine patients with 61 iCBS lesions were enrolled. Thirty-three iCBS lesions were treated with BES and 28 underwent PAO. The results for the BES group versus the PAO group, respectively, were: rebleeding events, 5/33 (15.1%) vs 5/28 (17.8%) (p=0.78); neurological complication, 5/33 (15.1%) vs 5/28 (17.8%) (p=0.78); median hemostatic time (months), 10.0 vs 11.5 (p=0.22); and median survival time (months), 10.0 vs 11.5 (p=0.39). CONCLUSIONS: No significant difference in rebleeding risk or neurological complication was observed between the BES and PAO groups. Our study confirmed the safety and effectiveness of applying BES for iCBS in HNC patients.

Shortened Cerebral Circulation Time Predicts Resistance to Obliteration in High-Flow Brain Arteriovenous Malformations After Stereotactic Radiosurgery.

BACKGROUND AND OBJECTIVES: Treatment selection for brain arteriovenous malformations (BAVMs) is complicated by BAVM size, location, and hemodynamics. Quantitative digital subtraction angiography is used to quantify the hemodynamic impact of BAVMs on cerebral circulation. This study investigated the association between cerebral circulation time and the complete obliteration (CO) rate of BAVMs after stereotactic radiosurgery (SRS). METHODS: We analyzed the data of 143 patients who underwent SRS for BAVMs between January 2011 and December 2019 in our institute. Their pre-SRS magnetic resonance imaging and angiography images were analyzed to acquire BAVM characteristics and quantitative digital subtraction angiography parameters. Modified cerebral circulation time (mCCT) was defined as the time difference between the bolus arrival time of the ipsilateral cavernous internal carotid artery and that of the parietal vein, as determined from the lateral view of images obtained using digital subtraction angiography. Cox regression with hazard ratios and Kaplan-Meier analyses were conducted to determine the associations between the parameters and BAVM CO after SRS. RESULTS: Of the 143 patients, 101 (70.6%) achieved BAVM CO. According to the multivariate analyses, an increased mCCT (hazard ratio: 1.24, P = .041) was the independent factor associated with BAVM CO after adjustment for age, sex, hemorrhagic presentation, a BAVM volume of >5 cm3, and a margin dose of >18 Gy. Individuals with an mCCT of ≤2.32 s had a lower 36-month probability of BAVM CO than did those with an mCCT of >2.32 s (44.1% ± 6.8% vs 63.3% ± 5.6%, P = .034). CONCLUSION: The hemodynamic impact of high-flow BAVM demonstrated by a shortened mCCT is associated with a lower BAVM CO rate after SRS.

Endovascular Management of Post-Irradiated Carotid Blowout Syndrome in Patients with Lower Neck Cancers.

OBJECTIVE: Lower neck cancers (LNCs) include specific tumour types and have some different vascular supply or collaterals from other head and neck cancers. This prospective study evaluated the outcome of endovascular management of post-irradiated carotid blowout syndrome (PCBS) in patients with LNC by comparing reconstructive management (RE) and deconstructive management (DE). METHODS: This was a single centre, prospective cohort study. Patients with LNC complicated by PCBS between 2015 and 2021 were enrolled for RE or DE. RE was performed by stent graft placement covering the pathological lesion and preventive external carotid artery (ECA) embolisation without balloon test occlusion (BTO). DE was performed after successful BTO by permanent coil or adhesive agent embolisation of the internal carotid artery (ICA) and ECA to common carotid artery, or ICA occlusion alone if the pathological lesion was ICA only. Cross occlusion included the proximal and distal ends of the pathological lesion in all patients. Re-bleeding events, haemostatic period, and neurological complications were evaluated. RESULTS: Fifty-nine patients (mean age 58.5 years; 56 male) were enrolled, including 28 patients undergoing RE and 31 patients undergoing DE. Three patients originally grouped to DE were transferred to RE owing to failed BTO. The results of RE vs. DE were as follows: rebleeding events, 13/28 (46%) vs. 10/31 (32%) (p = .27); haemostatic period, 9.4 ± 14.0 months vs. 14.2 ± 27.8 months (p = .59); neurological complication, 4/28 (14%) vs. 5/31 (16%) (p = .84); and survival time, 11.8 ± 14.6 months vs. 15.1 ± 27.5 months (p = .61). CONCLUSION: No difference in rebleeding risk or neurological complications was observed between the DE and RE groups. RE could be used as a potential routine treatment for PCBS in patients with LNC.

Percutaneous transluminal angioplasty and stenting of post-irradiated stenosis of subclavian artery: A matched case-control study.

BACKGROUND: Although radiotherapy is common for head/neck and chest cancers (HNCC), it can result in post-irradiation stenosis of the subclavian artery (PISSA). The efficacy of percutaneous transluminal angioplasty and stenting (PTAS) to treat severe PISSA is not well-clarified. AIMS: To compare the technical safety and outcomes of PTAS between patients with severe PISSA (RT group) and radiation-naïve counterparts (non-RT group). METHODS: During 2000 and 2021, we retrospectively enrolled patients with severe symptomatic stenosis (>60%) of the subclavian artery who underwent PTAS. The rate of new recent vertebrobasilar ischaemic lesions (NRVBIL), diagnosed on diffusion-weight imaging (DWI) within 24 h of postprocedural brain MRI; symptom relief; and long-term stent patency were compared between the two groups. RESULTS: Technical success was achieved in all 61 patients in the two groups. Compared with the non-RT group (44 cases, 44 lesions), the RT group (17 cases, 18 lesions) had longer stenoses (22.1 vs 11.1 mm, P = 0.003), more ulcerative plaques (38.9% vs 9.1%, P = 0.010), and more medial- or distal-segment stenoses (44.4% vs 9.1%, P<0.001). The technical safety and outcome between the non-RT group and the RT group were NRVBIL on DWI of periprocedural brain MRI 30.0% vs 23.1%, P = 0.727; symptom recurrence rate (mean follow-up 67.1 ± 50.0 months) 2.3% vs 11.8%, P = 0.185; and significant in-stent restenosis rate (>50%) 2.3% vs 11.1%, P = 0.200. CONCLUSION: The technical safety and outcome of PTAS for PISSA were not inferior to those of radiation-naïve counterparts. PTAS for PISSA is an effective treatment for medically refractory ischaemic symptoms of HNCC patients with PISSA.

Clinical and imaging findings for the evaluation of large Rathke's cleft cysts and cystic craniopharyngiomas.

PURPOSE: Large Rathke's cleft cysts (LRCCs) and cystic craniopharyngiomas (CCPs) arise from the same embryological origin and may have similar MR presentations. However, the two tumors have different management strategies and outcomes. This study was designed to evaluate the clinical and imaging findings of LRCCs and CCPs, aiming to evaluate their pretreatment diagnosis and outcomes. METHODS: We retrospectively enrolled 20 patients with LRCCs and 25 patients with CCPs. Both tumors had a maximal diameter of more than 20 mm. We evaluated the patients' clinical and MR imaging findings, including symptoms, management strategies, outcomes, anatomic growth patterns and signal changes. RESULTS: The age of onset for LRCCs versus CCPs was 49.0 ± 16.8 versus 34.2 ± 22.2 years (p = .022); the following outcomes were observed for LRCCs versus CCPs: (1) postoperative diabetes insipidus: 6/20 (30%) versus 17/25 (68%) (p = .006); and (2) posttreatment recurrence: 2/20 (10%) versus 10/25 (40%) (p = .025). The following MR findings were observed for LRCCs versus CCPs: (1) solid component: 7/20 (35%) versus 21/25 (84%) (p = .001); (2) thick cyst wall: 2/20 (10%) versus 12/25 (48%) (p = .009); (3) intracystic septation: 1/20 (5%) versus 8/25 (32%) (p = .030); (4) snowman shape: 18/20 (90%) versus 1/25 (4%) (p < .001); (5) off-midline extension: 0/0 (0%) versus 10/25 (40%) (p = .001); and (6) oblique angle of the sagittal long axis of the tumor: 89.9° versus 107.1° (p = .001). CONCLUSIONS: LRCCs can be differentiated from CCPs based on their clinical and imaging findings, especially their specific anatomical growth patterns. We suggest using the pretreatment diagnosis to select the appropriate surgical approach and thus improve the clinical outcome.

Prevention of in-stent restenosis with drug-eluting balloons in patients with postirradiated carotid stenosis accepting percutaneous angioplasty and stenting.

OBJECTIVE: To investigate the technical safety and outcome of in-stent restenosis (ISR) prevention with drug-eluting balloon (DEB) in patients with postirradiated carotid stenosis (PIRCS) undergoing percutaneous angioplasty and stenting (PTAS). METHODS: Between 2017 and 2021, we prospectively recruited patients with severe PIRCS for PTAS. They were randomly separated into two groups based on endovascular techniques performed with and without DEB. Preprocedural and early postprocedural (within 24 hours) MRI, short-term ultrasonography (6 months after PTAS), and long-term CT angiography (CTA)/MR angiography (MRA), 12 months after PTAS, were performed. Technical safety was evaluated based on periprocedural neurological complications and the number of recent embolic ischemic lesions (REIL) in the treated brain territory on diffusion-weighted imaging of early postprocedural MRI. RESULTS: Sixty-six (30 with and 36 without DEB) subjects were enrolled, with one failure in techniques. For 65 patients in the DEB versus conventional groups, technical neurological symptoms within 1 month (1/29 (3.4%) vs 0/36; P=0.197) and REIL numbers within 24 hours (1.0±2.1 vs 1.3±1.5; P=0.592) after PTAS showed no differences. Peak systolic velocity (PSVs) on short-term ultrasonography was significantly higher in the conventional group (104.13±42.76 vs .81.95±31.35; P=0.023). The degree of in-stent stenosis (45.93±20.86 vs 26.58±8.75; P<0.001) was higher, and there were more subjects (n=8, 38.9% vs 1, 3.4%; P=0.029) with significant ISR (≥ 50%) in the conventional group than in the DEB group on long-term CTA/MRA. CONCLUSIONS: We observed similar technical safety of carotid PTAS with and without DEBs. The number of cases of significant ISR were fewer and the degree of stenosis of ISR was less in primary DEB-PTAS of PIRCS than for conventional PTAS in the 12-month follow-up.

Percutaneous transluminal angioplasty and stenting of post-irradiation stenosis of the vertebral artery.

BACKGROUND: The outcomes of percutaneous transluminal angioplasty and stenting (PTAS) in patients with medically refractory post-irradiation stenosis of the vertebral artery (PISVA) have not been clarified. AIM: This retrospective study evaluated the safety and outcomes of PTAS in patients with severe PISVA compared with their radiation-naïve counterparts (non-RT group). METHODS: Patients with medically refractory severe symptomatic vertebral artery stenosis and undergoing PTAS between 2000 and 2021 were classified as the PISVA group or the non-RT group. The periprocedural neurological complications, periprocedural brain magnetic resonance imaging, the extent of symptom relief, and long-term stent patency were compared. RESULTS: As compared with the non-RT group (22 cases, 24 lesions), the PISVA group (10 cases, 10 lesions) was younger (62.0 ± 8.6 vs 72.4 ± 9.7 years, P = 0.006) and less frequently had hypertension (40.0% vs 86.4%, P = 0.013) and diabetes mellitus (10.0% vs 54.6%, P = 0.024). Periprocedural embolic infarction was not significantly different between the non-RT group and the PISVA group (37.5% vs 35.7%, P = 1.000). At a mean follow-up of 72.1 ± 58.7 (3-244) months, there was no significant between-group differences in the symptom recurrence rate (0.00% vs 4.55%, P = 1.000) and in-stent restenosis rate (10.0% vs 12.5%, P = 1.000). CONCLUSION: PTAS of severe medically refractory PISVA is effective in the management of vertebrobasilar ischemic symptoms in head and neck cancer patients. Technical safety and outcome of the procedure were like those features in radiation-naïve patients.

Outflow Patency Correlates with Radiosurgical Outcomes of Lateral Sinus Dural Arteriovenous Fistula.

OBJECTIVE: To explore the impact of outflow patency on radiosurgical outcomes of lateral sinus dural arteriovenous fistulas (DAVFs). METHODS: We retrospectively examined 83 lateral sinus DAVFs treated with Gamma Knife radiosurgery (GKRS) between 1995 and 2020. Two neuroradiologists blinded to the therapeutic outcomes served as imaging evaluators on pre-GKRS digital subtraction angiography and magnetic resonance images. The sinovenous outflow of lateral sinus DAVF was scored using combined conduit score (CCS), ranging from 0 (total occlusion) to 8 (full patency). The patients' follow-up magnetic resonance and digital subtraction angiography images were used to validate the radiosurgical outcomes (obliteration or non-obliteration) of lateral sinus DAVF. Cox regression and Kaplan-Meier analyses were performed to determine the correlations between the variables and outcomes. RESULTS: Among the 83 cases, 60 (72%) lateral sinus DAVFs achieved obliteration after a GKRS at a median latency period of 24.5 months. After adjustment for aggressive presentation, cortical venous reflux, straight sinus reflux, and optic nerve sheath enlargement, a CCS of >6 was independently associated with lateral sinus DAVF obliteration (hazard ratio: 2.335, P = 0.007). The estimated 36-month probabilities of obliteration were 80% versus 53.6% for lateral sinus DAVFs with a CCS of >6 versus ≤6. CONCLUSIONS: Lateral sinus DAVFs with a CCS of >6, indicating a nearly patent sinovenous outflow, were more likely to be obliterated after GKRS. Sinovenous outflow patency is a factor associated with therapeutic outcomes in radiosurgery for lateral sinus DAVFs.

Sinovenous outflow in lateral sinus dural arteriovenous fistulas after stereotactic radiosurgery: a retrospective longitudinal imaging study.

PURPOSE: To investigate sinovenous outflow restriction (SOR) in lateral sinus dural arteriovenous fistulas (LSDAVFs) after Gamma Knife radiosurgery (GKRS) and its association with complete obliteration. METHODS: We retrospectively (1995-2019) enrolled 39 patients with LSDAVFs who had undergone GKRS alone and evaluated their angiography and magnetic resonance imaging (MRI) before and after GKRS. The LS conduits ipsilateral and contralateral to the DAVFs were scored using a 5-point scoring system, with scores ranging from 0 (total occlusion) to 4 (fully patent). SOR was defined by a conduit score < 2. Demographics, imaging features, and outcomes were compared between patients with and without ipsilateral SOR after GKRS. Logistic regression analysis was performed to estimate the odds ratio (OR) for obliteration with the imaging findings. RESULTS: After a median angiographic follow-up of 28 months for the 39 patients, the ipsilateral LS became more restrictive (median conduit score before and after GKRS: 2 vs. 1, p = .011). Twenty-one patients with ipsilateral SOR after GKRS had a significantly lower obliteration rate (52.4% vs. 94.4%, p = .005) than those without SOR. Follow-up SOR was independently associated with a lower obliteration rate (OR 0.05, p = .017) after adjustment for age, cortical venous reflux, and absent sinus flow void on MRI. CONCLUSION: This study demonstrates a restrictive change of outflow in LSDAVFs after GKRS and a lower obliteration rate in patients with SOR. Follow-up imaging for SOR may help predict outcomes of these patients.

Imaging Markers Associated With Radiation-Induced Changes in Brain Arteriovenous Malformations After Radiosurgery.

BACKGROUND: Radiation-induced changes (RICs) in brain tissue, seen as increased perinidal T2-weighted hyperintensity on MRI, are commonly observed in patients with brain arteriovenous malformations (BAVMs) within 2 years after Gamma Knife (Elekta) radiosurgery (GKRS). OBJECTIVE: To explore the imaging markers associated with RICs in patients with BAVMs. METHODS: We retrospectively included 106 treatment-naïve patients with BAVMs who received GKRS alone between 2011 and 2018 and had ≥24 months of clinical and MRI follow-up. Pre-GKRS angiography and MRIs were analyzed for morphological characteristics and quantitative digital subtraction angiography parameters. RIC severity was categorized as mild (grade I), moderate (grade II), or severe (grade III). Firth logistic regression analysis was conducted to determine the associations between the parameters and RICs. RESULTS: Among the 106 patients, 83 (78.3%) developed RICs, with 16 categorized as grade I, 62 as grade II, and 5 as grade III. RICs were symptomatic in 19 patients (17.9%). In multivariable models, BAVMs with a volume of >5 cm3 (odds ratio [OR]: 4.322, P = .024) and neoangiogenesis on angiography before treatment (OR: 3.846, P = .029), and thrombus within nidus or drainage vein on follow-up MRI (OR: 3.679, P = .001) were independently associated with grade II or III RICs. Symptomatic RICs were more likely to develop in basal ganglia or brainstem. CONCLUSION: Large BAVMs and neoangiogenesis were associated with moderate to severe RICs in treatment-naïve patients with BAVMs. Our findings may assist with the complication risk assessment for these patients.

Risk factors of recurrent carotid blowout syndrome and strategy of endovascular management.

BACKGROUND: Carotid blowout syndrome (CBS) is a catastrophic complication after aggressive head and neck cancer treatment. Endovascular embolization is an effective modality to manage CBS. However, some CBS may have recurrent CBS (rCBS) after endovascular management. This study aims to report the potential rCBS risk and endovascular management strategy. METHODS: Of the 225 patients with CBS referred for embolization in 13 years, 31 men and one woman (mean age, 55 years) with 35 rCBS with pseudoaneurysms formation were identified after endovascular management. Moreover, the rCBS preembolization angioarchitecture, rCBS cause, rCBS time interval, embolic materials selection, and final embolization clinical/angiographic outcomes were retrospectively analyzed. RESULTS: rCBS with pseudoaneurysm due to disease progression (DP) occurred in 17 patients, while 15 patients had insufficient embolization (IE) with 18 rCBS. The mean rCBS timing interval was 76 days with 129 and 12 days due to DP or IE. The most common rCBS locations were the carotid bulb and the main trunk of the external carotid artery (n = 20, 57%), followed by internal carotid artery (n = 8, 23%), distal branch of the external carotid artery (n = 4, 11%), and common carotid artery (n = 3, 9%). Endovascular management was technically successful in all patients by reconstruction (n = 7, 20%) or destruction (n = 28, 80%) techniques. Three patients (9%) had procedure-related complications. No rCBS was observed in all affected arteries after the last embolization in a mean 11-month clinical follow-up. CONCLUSION: rCBS may result from DP or IE. The common location of IE-related rCBS usually occurred in the carotid branches. It occurred within two weeks of CBS largely because of the underestimation of the extension of the affected carotid artery. In addition, DP is natural in head and neck cancer after aggressive treatment. Thus, endovascular management remained an effective method to manage rCBS.

Diagnosis of extracranial carotid stenosis by MRA of the brain.

Severe extracranial carotid stenosis (SECS) patients may present with nonspecific neurological symptoms that require intracranial magnetic resonance imaging (MRI) and time-of-flight (TOF)-MR angiography (MRA) to exclude intracranial pathology. Recognition of SECS on intracranial TOF-MRA findings is beneficial to provide a prompt carotid imaging study and aggressive stroke prevention. Patients with SECS (January 2016 to May 2019) undergoing percutaneous transluminal angioplasty and stenting (PTAS) were included. Differences in normalized signal intensities (SRICA) and diameters (DICA) between bilateral petrous internal carotid arteries (ICAs) were calculated 1 cm from the orifice. A hypothesized criterion describing the opacification grades (GOPH) of bilateral ophthalmic arteries was proposed. We correlated SRICA (p = 0.041), DICA (p = 0.001) and GOPH (p = 0.012), with the severity of extracranial carotid stenosis on digital subtractive angiography (DSA) in the examined group (n = 113), and all showed statistical significance in predicting percentages of ICA stenosis. The results were further validated in another patient group with SECS after radiation therapy (n = 20; p = 0.704 between the actual and predicted stenosis grades). Our findings support the evaluation of the signal ratio and diameter of intracranial ICA on TOF-MRA to achieve early diagnosis and provide appropriate management of SECS.

Long-term imaging follow-up to evaluate restenosis in patients with carotid stenosis after angioplasty and stenting.

BACKGROUND: Stent patency after carotid angioplasty and stenting (CAS) correlates not only with stroke prevention but also with improvements in cognition and quality of life by positively influencing cerebral perfusion. The long-term outcomes of CAS after more than 5 years have still not been well described. This retrospective study was designed to evaluate the stent patency and significant restenosis (SR) after CAS with more than 5 years of follow-up. METHODS: Between 2006 and 2012, 118 patients with carotid stenosis who underwent 131 CAS procedures with regular annual imaging follow-up for more than 5 years were enrolled. We evaluated their demographic characteristics and the risk factors related to stent restenosis. Patients with SR (restenosis ≥ 50%) were compared with those with no significant restenosis (NSR, patency or restenosis < 50%) to identify the restenosis predictors and restenosis-free survival. RESULTS: Of the 131 CAS procedures, 16.0% (21/131) had SR. A history of head and neck radiotherapy (HNRT) was a predictor for SR (HR, 6.352; 95% CI, 2.504-16.112; p < 0.001) and was associated with shorter restenosis-free survival (log-rank test p value < 0.001, median time of restenosis-free survival was 38 months). Left-sided stenting was an associated factor for SR (HR, 3.007; 95% CI, 1.068-8.467; p = 0.037) with a trend of less restenosis-free survival (log-rank test p value 0.067). CONCLUSION: Both HNRT and left-sided carotid stenosis were predictors of SR after CAS in more than 5 years of long-term follow-up. Restenosis-free survival was significantly shorter in patients with prior HNRT than in patients without previous irradiation treatment. We suggest close follow-up and aggressive medical treatment for patients with prior HNRT and left-sided carotid stenosis undergoing CAS.

Endovascular management of symptomatic stenosis of supra-aortic arteries in patients with Takayasu arteritis.

BACKGROUND: Endovascular management is used to treat Takayasu arteritis (TA) involving the supra-aortic branches. However, the long-term outcome of this treatment remains unclear. Here, technical safety, outcomes, and restenosis management of supra-aortic arteries in TA patients receiving endovascular treatment were evaluated. METHODS: TA patients with symptomatic supra-aortic stenosis who underwent percutaneous angioplasty and stenting between 2008 and 2018 at our institute were enrolled in this study. Pre- and post-procedural magnetic resonance imaging (MRI) evaluations, including high-resolution vessel wall imaging (HR-VWI), were performed. Technical efficacy, peri-procedural complications, early post-procedural MRI results, and stent patency were examined. RESULTS: All six patients successfully received stent placement or percutaneous transluminal angioplasty in a total of 22 treated arteries without neurologic complications. During follow-up (mean, 56.3 ± 41.1 months), no recurrent stroke occurred, yet significant restenosis developed in 12 of 22 (54.5%) of the treated arteries. Three of the patients underwent HR-VWI before surgery. Concentric wall thickening and enhancement of the left common carotid artery was detected in one patient, indicating acute inflammation. Angioplasty with drug-eluting balloon (DEB) successfully treated a case of refractory restenosis. Among 10 early post-procedure MRI performed, only two asymptomatic new lesions were detected with diffusion-weighted imaging. CONCLUSION: Endovascular treatment of supra-aortic arteries of TA patients was safe and effective, yet was associated with a high restenosis rate. Thus, close follow-up is needed. HR-VWI is helpful for pre-procedural selection of patients for percutaneous angioplasty and stenting and drug-eluting balloon angioplasty appears to be a promising treatment for refractory in-stent restenosis.

Magnetic resonance imaging as a single diagnostic tool for verifying radiosurgery outcomes of cavernous sinus dural arteriovenous fistula.

PURPOSE: MRI and MR angiography (MRA) are noninvasive methods for examining cavernous sinus dural arteriovenous fistulas (CSDAVFs) after radiosurgery. In this study, we investigated the accuracy of unenhanced MRI/3-dimensional time-of-flight (3D TOF) MRA in evaluating CSDAVF obliteration as compared with digital subtraction angiography (DSA). METHODS: From 1995-2012, 48 cases of CSDAVFs received Gamma Knife surgery (GKS) and had undergone both unenhanced MRI/3D TOF MRA and DSA for posttreatment evaluation. Two blinded observers independently interpreted the results of MRI/MRA. The results of MRI/MRA were compared with those of DSA. The sensitivity (the probability of MRI/MRA showing obliteration when DSA showed complete obliteration), specificity, positive predictive value, and negative predictive value for CSDAVF obliteration were reported. RESULTS: The median interval between the final MRI/MRA and the subsequent DSA was 2 months. Follow-up DSA revealed that 38 of 48 (79.2 %) CSDAVFs were completely obliterated. The results of interobserver agreement assessment showed almost perfect agreement between the 2 observers. For unenhanced MRI/3D TOF MRA, the observed sensitivity was 84.2 %, specificity was 100 %, positive predictive value was 100 %, and negative predictive value was 62.5 %. CONCLUSIONS: Unenhanced MRI/3D TOF MRA alone may be adequate to document the complete obliteration of CSDAVFs after GKS. Time-resolved MRA or DSA can be reserved for a suspected residual CSDAVF after a sufficient latency period after GKS.

Stagnant Venous Outflow Predicts Brain Arteriovenous Malformation Obliteration After Gamma Knife Radiosurgery Without Prior Intervention.

BACKGROUND: Gamma Knife radiosurgery (GKRS) obliterates 65% to 82% of brain arteriovenous malformations (BAVMs). OBJECTIVE: To explore the impact of hemodynamics on GKRS outcomes. METHODS: We retrospectively (2011-2017) included 98 patients with BAVMs who had received GKRS alone. Two evaluators, blinded to the outcomes, analyzed the pre-GKRS angiography and magnetic resonance images to obtain the morphological characteristics and quantitative digital subtraction angiography (QDSA) parameters. The venous stasis index was defined as the inflow gradient divided by the absolute value of the outflow gradient. Patients' follow-up magnetic resonance or digital subtraction angiography images were evaluated for the presence of complete obliteration (CO). Cox regression and Kaplan-Meier analyses were conducted to determine the correlations between the parameters and outcomes. RESULTS: Among the 98 patients, 63 (63.4%) achieved CO after GKRS at a median latency period of 31 mo. In multivariable analyses with adjustments for age and sex, increased BAVM volume (hazard ratio (HR) 0.949, P = .022) was an independent characteristic predictor, and venous stenosis (HR 2.595, P = .009), venous rerouting (HR 0.375, P = .022), and larger stasis index (HR 1.227, P = .025) were independent angiographic predictors of CO. BAVMs with a stasis index of >1.71 had a higher 36-mo probability of CO than those with a stasis index of ≤1.71 (61.1% vs 26.7%, P < .001). CONCLUSION: BAVMs with a larger stasis index, indicating more stagnant venous outflow, may predict obliteration after GKRS. QDSA analysis may help in predicting BAVM treatment outcomes and making therapeutic decisions.

Pseudoaneurysm of the basilar artery presenting with epistaxis.

The internal carotid artery is the most commonly affected artery in pseudoaneurysm presenting with epistaxis. Basilar arterial pseudoaneurysm is usually associated with intracranial haemorrhage. We report a basilar artery pseudoaneurysm after endoscopic surgery for clival chordoma, leading to epistaxis. The mechanism of epistaxis and strategy of embolisation are discussed.

Treatment Outcomes of Cavernous Sinus Dural Arteriovenous Fistulas: Comparison of Radiosurgery and Endovascular Embolisation.

BACKGROUND AND PURPOSE: Endovascular treatment (EVT) and stereotaxic gamma-knife radiosurgery (GKRS) can both effectively treat cavernous sinus dural arteriovenous fistulas (CSDAVF). This study compared the prognostic factors and treatment effectiveness of GKRS and EVT for different CSDAVF types. METHODS: The charts of 200 patients undergoing GKRS and 105 patients undergoing EVT were reviewed for data on symptoms (e.g. orbital, cavernous, ocular, and cerebral). The CSDAVFs were classified into proliferative, restrictive, and late restrictive types. The prognostic factors for complete obliteration (CO) were evaluated in both the GKRS and EVT groups and the latent period to CO was measured. For statistical analysis χ2-tests were used to compare final CO rates for EVT and GKRS across the three CSDAVF types. RESULTS: The EVT and cavernous symptoms were significant independent predictors of CO. The CO rate after EVT (97.9%) was significantly higher than that after GKRS (63.5%) for restrictive CSDAVFs (P < 0.001) but not for proliferative or late restrictive types. In the GKRS group, cavernous symptoms (hazard ratio, HR: 0.557) and target volume (HR: 0.853) predicted CO, but only target volume remained significant in multivariate analysis. In the EVT group, the latent period to CO was shortest for restrictive CSDAVFs (3.2 ± 1.6 months, P = 0.05). CONCLUSION: Angioarchitecture did not affect treatment outcomes. Cavernous symptoms were strongly associated with lower complete obliteration rates in the GKRS but not the EVT group. The EVT method remains the treatment of choice, especially for restrictive CSDAVFs; however, compared to EVT, GKRS had lower complication rates and similar therapeutic effects for proliferative type fistulas.

Prognostic factors related to intratumoral hemorrhage in pediatric intracranial germ cell tumors.

BACKGROUND: Certain types of pediatric intracranial germ cell tumors (PIGCTs) are prone to intratumoral hemorrhaging (TH) and associated with poor survival outcome. However, the impact of TH on the functional prognosis of patients with PIGCTs has not been well studied. This study aimed to evaluate the clinical and MR findings in PIGCT patients with TH to identify the factors related to patient survival and functional outcome. METHODS: This study included 17 patients diagnosed with PIGCT and TH between 2002 and 2016 and evaluated TH-associated clinical and MR findings. The modified Rankin scale (mRS) was used to evaluate functional outcome, which was poor when mRS ≧ 3. The volumes of hematomas and tumors were manually tracked within each brain magnetic resonance imaging slice. RESULTS: Among the 17 patients, 6 (35.3%) died and 9 (52.9%) had poor functional outcome. Regarding the functional outcome, the mean hematoma volume to tumor volume ratio (HTVR) was 8.5 ± 3.9% in the favorable outcome group and 42.3 ± 27.8% in the poor outcome group (p = 0.001). For the survival outcome, the mean HTVR was 15.7 ± 16.1% in the living group and 46.0 ± 31.5% in the deceased group (p = 0.016). The cutoff point of the receiver operating characteristics curve for HTVR to predict death and poor functional outcome was 19.27% and 16.8%, respectively. CONCLUSION: Our study demonstrated that patients with larger HTVR had significantly worse functional and survival outcomes than those with smaller HTVR. We suggest that early and aggressive treatment for PIGCTs in patients with large HTVR can improve their long-term prognosis.