Correction: Recurrence pattern predicts aneurysm rupture after coil embolization.

[This corrects the article DOI: 10.1371/journal.pone.0261996.].

Recurrence of an extracranial internal carotid artery aneurysm treated with STA-MCA bypass and trapping due to neovascularization from an ascending pharyngeal artery: illustrative case.

BACKGROUND: Extracranial internal carotid artery aneurysms (EICAs) are rare. Although a high mortality risk has been reported in nonoperated cases, the optimal treatment for EICAs remains unknown. OBSERVATIONS: A 79-year-old female presented with painless swelling in the right neck. Imaging revealed a giant EICA with a maximum diameter of 3.2 cm. Superficial temporal artery-middle cerebral artery bypass and internal carotid artery (ICA) trapping were performed. Because the distal aneurysm edge was at the C1 level, the distal portion of the aneurysm was occluded by endovascular coiling, and the proximal portion was surgically ligated. Blood flow into the aneurysm disappeared after the operation. Three years postsurgery, enlargement of the aneurysm with blood flow from the ascending pharyngeal artery (APA) was detected. The EICA was resected after coiling the APA and ligating both ends of the aneurysm. Pathologically, neovascularization within the aneurysm wall was observed. LESSONS: Even if blood flow into an EICA disappears after ICA trapping, the EICAs can enlarge due to neovascularization from the neighboring artery. From the outset, removal of the aneurysm should be considered as a radical treatment strategy for giant EICAs.

Recurrence pattern predicts aneurysm rupture after coil embolization.

INTRODUCTION: Hemorrhage from a recurrent aneurysm is a major concern after coiling for intracranial aneurysms. We aimed to identify aneurysm recurrence patterns associated with hemorrhage. MATERIAL AND METHODS: We investigated radiological data of patients who underwent coiling for intracranial aneurysms in 2008-2016 and were followed-up for at least 6 months. Aneurysm recurrence patterns were classified as: type Ⅰ, enlargement of aneurysm neck; type Ⅱ, recurrent cavity within the coil mass; type Ⅲ, recurrent cavity along the aneurysm wall; and type Ⅳ, formation of a daughter sac. We evaluated the incidence of various recurrence patterns with or without hemorrhage. RESULTS: Of the 173 aneurysms included in the study (mean follow-up period, 32 months; range, 6-99 months), 22 (13%) recurred and required re-treatment. The recurrence patterns included type Ⅰ, Ⅱ, Ⅲ, and Ⅳ in 7 (4%), 4 (2%), 9 (5%), and 2 (1%) cases, respectively. Most of the type Ⅰ, Ⅱ, and Ⅲ recurrences occurred within 1 year, and type Ⅳ occurred at 7 years after coiling. Three aneurysms exhibited hemorrhage, one with type Ⅲ and two with type Ⅳ pattern. The two aneurysms with type Ⅳ recurrence initially occurred as type Ⅰ; however, the recurrent neck enlarged gradually, resulting in new sac formation. CONCLUSIONS: We recommend prompt re-treatment for aneurysms recurring with type Ⅲ or Ⅳ patterns, as such patterns were associated with hemorrhage. Furthermore, we need a special care to type Ⅰ recurrence with enlargement of recurrent neck because this specific pattern may develop to type Ⅳ.

Hypertrophic Pachymeningitis with Characteristics of Both IgG4-related Disorders and Granulomatosis with Polyangiitis.

We herein report a 73-year-old man with isolated hypertrophic pachymeningitis (HP) showing serological and pathological characteristics of both IgG4-related disorders and granulomatosis with polyangiitis. The patient presented with chronic onset headaches and ophthalmalgia. Brain magnetic resonance imaging (MRI) revealed a hypertrophic enhanced dura mater. Serum IgG4 and myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA) levels were elevated. A dura mater biopsy showed infiltration of numerous IgG4-positive plasma cells and granulomatous inflammation without apparent vasculitic lesions, storiform fibrosis, or obstructive phlebitis. Corticosteroid treatments improved his clinical symptoms and MRI findings. There have been reports of MPO-ANCA-positive IgG4-related HP presenting as granulomatous inflammation in the dura mater.

Limb-shaking syndrome derived from the contralateral hemisphere following unilateral revascularisation for moyamoya disease.

BACKGROUND: Moyamoya disease is a rare chronic steno-occlusive cerebrovascular disease. It may have variable clinical symptoms associated with cerebral stroke, including motor paralysis, sensory disturbances, seizures, or headaches. However, patients with moyamoya disease rarely present with involuntary movement disorders, including limb-shaking syndrome, with no previous reports of limb-shaking syndrome occurring after revascularization procedures for this disease. Although watershed shifts can elicit transient neurological deterioration after revascularisation, symptoms originating from the contralateral hemisphere following the revascularization procedure are rare. Here, we report the case of moyamoya disease wherein the patient developed limb-shaking syndrome derived from the contralateral hemisphere after unilateral revascularisation. CASE DESCRIPTION: A 16-year-old girl presented with transient left upper and lower limb numbness and headache. Based on digital subtraction angiography, she was diagnosed with symptomatic moyamoya disease. Single-photon emission computed tomography (SPECT) showed decreased cerebral blood flow (CBF) on the right side, and she underwent direct and indirect bypasses on this side. Involuntary movements appeared in her right upper limb immediately postoperatively. SPECT showed decreased CBF to the bilateral frontal lobes. Subsequently, the patient was diagnosed with limb-shaking syndrome. After performing left-hemispheric revascularisation, the patient's symptoms resolved, and SPECT imaging confirmed improvements in CBF to the bilateral frontal lobes. CONCLUSION: Revascularization for moyamoya disease can lead to watershed shifts, which can induce limb-shaking syndrome derived from abnormalities in the contralateral hemisphere of the revascularized side. For patients with new-onset limb-shaking syndrome after moyamoya revascularisation procedures, additional revascularization may be warranted for treatment of low perfusion areas.

Spinal Accessory Nerve Meningioma at the Foramen Magnum with Medullar Compression: A Case Report and Literature Review.

BACKGROUND: Meningiomas that arise from the cranial nerve are rare. We present a case with an intradural extramedullary tumor at the foramen magnum originating from the spinal accessory nerve. CASE DESCRIPTION: The patient was a 69-year-old woman with dizziness and pain in the bilateral shoulder for 2 years. Neurologic examination revealed spinal accessory nerve palsy (difficult in raising the shoulder, deficit of 3/5) on the left side without further deficits. Magnetic resonance imaging showed medullar compression because of a left intradural extramedullary foramen magnum lesion dorsolateral to the medulla. Surgical exposure via a midline suboccipital approach with C1 laminectomy revealed that the lesion arises from the left accessory nerve without dural attachment. The tumor was resected without injury to the spinal accessory nerve, and histologic examination revealed that it was a meningothelial meningioma. The spinal accessory nerve palsy improved to 4 of 5 after 3 months after surgery. CONCLUSIONS: To our knowledge, this is the first report of an accessory nerve meningioma at the foramen magnum in which the spinal accessory nerve palsy appeared before operation and improved after tumor resection.

Intraorbital Solitary Fibrous Tumor Requiring Preoperative Embolization of Feeding Artery.

Solitary fibrous tumors (SFTs) are derived from mesenchymal cells and commonly develop in thoracoabdominal organs; however, their occurrence in orbit is rare. The first-choice treatment is to surgically remove as much of the SFT as possible; however, if total removal is not achieved, the recurrence rate is high, resulting in poor prognosis. A 42-year-old man presented with painless right-sided proptosis and diplopia 4 years ago. Orbital computed tomography revealed a right extraconal mass medial to the optic nerve, measuring 25 mm. Magnetic resonance imaging demonstrated iso-signal intensity on T1- and T2-weighted imaging, including flow-void signals. During biopsy of the intraorbital mass, which was performed by ophthalmologists 3 years earlier, difficulty with hemostasis occurred due to massive hemorrhage from the mass. The mass grew to reach a maximal diameter of 33 mm, resulting in referral to the authors' department. Diagnostic cerebral angiography revealed a hypervascular orbital tumor with multiple feeding arteries. To control intraoperative bleeding, the patient underwent preoperative endovascular embolization. Subsequently, the tumor was completely removed using a combination of microsurgical craniotomy and endoscopic endonasal approach, without the occurrence of massive intraoperative hemorrhage from the tumor. Postoperatively, his clinical course was uneventful except for the remaining preoperative diplopia. The tumor was diagnosed histologically as SFT and has not recurred for 8 months since surgery. Preoperative intravascular embolization of branches of the ophthalmic artery can be performed safely, resulting in excellent control of intraoperative bleeding and facilitating complete removal of SFT without additional complications.

High Pressure in Virtual Postcoiling Model is a Predictor of Internal Carotid Artery Aneurysm Recurrence After Coiling.

BACKGROUND: Hemodynamic factors play a crucial role in the recurrence of intracranial aneurysms after coiling. However, the strongest factor for predicting recurrence remains unclear because each risk factor has been investigated and reported separately. OBJECTIVE: To clarify the strongest predictor of recurrence with computational fluid dynamics (CFD). METHODS: Using pretreatment patient-specific 3-dimensional rotational angiography data of 50 internal carotid artery (ICA) aneurysms (7 recanalized, 43 stable) treated with endovascular coiling, we created a precoiling model and a virtual postcoiling model produced by manually cutting the aneurysm by the flat plane corresponding to the virtual coil surface. We conducted CFD analysis to investigate inflow dynamics in the precoiling model and pressure difference and wall shear stress on the virtual coil surface. The pressure difference was calculated by subtracting average pressure at the proximal ICA from the maximum pressure at the coil surface and dividing by dynamic pressure at the proximal ICA for normalization. We compared hemodynamic parameters in both models between recanalized and stable aneurysms. RESULTS: Compared with stable aneurysms, recanalized aneurysms showed a significantly larger inflow area and higher inflow rate in the precoiling model (P = .016, .028), and higher pressure difference at the coil surface in the postcoiling model (P < .001). The receiver-operating characteristic analysis showed that the area under the curve value for the pressure difference (0.967) was superior to that of other evaluated parameters. CONCLUSION: The pressure difference in the virtual postcoiling model may be a strong predictor of recurrence after coiling.

Hyperperfusion syndrome after trapping with high-flow bypass for a giant paraclinoid internal carotid artery aneurysm.

BACKGROUND: Hyperperfusion syndrome associated with aneurysm surgery is rare. The occurrence of the syndrome after trapping with high-flow bypass has not been described previously. Herein, we present a case of the syndrome that occurred after trapping with high-flow bypass of an unruptured giant paraclinoid internal carotid artery (ICA) aneurysm. CASE DESCRIPTION: The patient was a 68-year-old woman with progressive loss of vision in her left eye. After a diagnosis of left giant ICA aneurysm, she underwent successful trapping with high-flow bypass. No new neurologic deficits were observed after surgery. Computed tomography on the same day and magnetic resonance imaging on the next day revealed no hemorrhage or infarction. The patient had a headache and transit motor aphasia on postoperative day (POD) 8. Arterial spin-labeling magnetic resonance perfusion imaging on the same day and single photon emission CT on POD 10 demonstrated hyperperfusion in the left cerebral cortex. The symptoms gradually improved over a week, and she had no new neurologic deficits when discharged from hospital. CONCLUSIONS: This report suggests that hyperperfusion syndrome after trapping with high-flow bypass, although rare, should be considered in patients with giant aneurysm if they present with headache and neurologic deficits after a delay.

Objective evaluation of cerebrovascular reactivity for acetazolamide predicts cerebral hyperperfusion after carotid artery stenting: Comparison with region of interest methods.

BACKGROUND AND PURPOSE: Hemodynamic impairments are considered risk factors of cerebral hyperperfusion after carotid artery stenting (CAS); measurement by Single-photon emission computed tomography (SPECT) using a subjective region of interest (ROI) method lacks consistency and reproducibility. MATERIALS AND METHODS: The present study compared objective perfusion analysis (stereotactic extraction estimation [SEE] method) with the ROI method for preoperative SPECT to predict the hyperperfusion phenomenon (HPP) after CAS. Preoperative resting asymmetry index (cerebral blood flow [CBF] ratio from the affected to unaffected hemisphere) and cerebrovascular reactivity (CVR) to acetazolamide were measured by N-isopropyl-p-[123I]-iodoamphetamine SPECT using the SEE and ROI method in 84 patients. CBF was also measured the day after CAS. Perfusion data with the highest area under the curve (AUC) by receiver-operating characteristic (ROC) analysis was considered a perfusion risk factor of HPP. Multivariate analyses for clinical characteristics and perfusion risk factors were performed to determine predictors of HPP. RESULTS: The HPP was observed in 10 patients (11.9%). Female sex, contralateral stenosis, and degree of stenosis were significantly associated with HPP development on univariate analysis, and symptomatic stenosis was not found to be a significant factor. On SPECT analysis, CVR in the MCA area by SEE method had the highest AUC (0.981). Multivariate analysis showed that CVR in the MCA area was a significant predictor of HPP (P=0.041). To predict hyperperfusion, the ROC curve of the CVR showed a cutoff value of -0.60%, sensitivity of 94.6%, and specificity of 100% (P<0.001). CONCLUSIONS: Objective SEE method had better a predictive capability than ROI method to identify risk of hyperperfusion after CAS.

Physical Risk Factors of Hemorrhagic Complications Associated with Angio-Seal Closure Device Use in Neurointerventional Procedures.

BACKGROUND: Few studies have demonstrated detailed physical risk factors of hemorrhagic complications (HCs) associated with the Angio-Seal closure device. This retrospective study aimed to identify the risk factors of HC due to Angio-Seal use. METHODS: Data from 143 cases that underwent neurointerventional procedures that involved puncturing the femoral artery and that used an Angio-Seal to close the puncture site were reviewed. We divided these cases into HC and no HC groups and retrospectively compared age, sex, past medical and preference history, body mass index (BMI), femoral artery depth, dual antiplatelet therapy use, activated clotting time, general anesthesia use, sheath size, right femoral artery puncture, and treatment time. RESULTS: HC occurred in 7 cases, 2 of which were excluded because of technical failure. Accordingly, we examined physical risk factors in 5 cases (3.5%) in the HC group and in 136 cases (96.5%) in the no HC group. A low BMI and shallow femoral artery depth were significantly associated with HC, whereas the other factors were not. A receiver operating characteristic curve indicated that a BMI cut-off value of 20.98 and a femoral artery depth of 11.1 mm could achieve optimal diagnostic efficiency for predicting HC. CONCLUSIONS: Patients with a BMI <21 may require careful hemostasis monitoring, and it is better not to undergo arterial puncture site closure using Angio-Seal for those with a femoral artery depth <11.1 mm.

A Pediatric Case of Reversible Cerebral Vasoconstriction Syndrome With Similar Radiographic Findings to Posterior Reversible Encephalopathy Syndrome.

BACKGROUND: Reversible cerebral vasoconstriction syndrome occurs predominantly in middle-aged women. Only nine pediatric patients with this syndrome have been reported. PATIENT DESCRIPTION: We present a ten-year-old boy with reversible cerebral vasoconstriction syndrome with radiographic findings similar to those of posterior reversible encephalopathy syndrome (PRES). He presented with a thunderclap headache without a neurological deficit. Brain magnetic resonance angiography (MRA) revealed multifocal narrowing of the cerebral arteries, whereas magnetic resonance imaging (MRI) with diffusion-weighted imaging and fluid-attenuated inversion recovery demonstrated hyperintense lesions in the occipital lobes and the left cerebellum. The patient's symptoms resolved spontaneously after a few hours with no recurrence. MRA on the second day showed a complete normalization of the affected arteries, and MRI after one month demonstrated improvement in the abnormal findings, leading to a diagnosis of RCVS with radiographic findings similar to those of PRES. CONCLUSIONS: This child's findings suggests that, RCVS, with or without PRES, may occur in children who present with a thunderclap headache.

Long-term predictive factors of the morphology based outcome in bare platinum coiled intracranial aneurysms: Evaluation by pre- and post-contrast 3D time-of-flight MR angiography.

PURPOSE: Our aim was to identify long-term predictive factors of the morphology-based outcome (MBO) of bare platinum coiled intracranial aneurysms. MATERIALS AND METHODS: A retrospective analysis of 96 bare platinum coiled intracranial aneurysms followed up from 1997 to 2016 using pre- and post-contrast 3D time-of-flight MR angiography (MRA) was performed. Logistic regression analysis was used to identify factors associated with a positive history of surrounding coil mass enhancement (SCME) and poor MBO. Spearman's rank correlation test was used to analyze the relationship between the initial angiographic result (IAR) class, sequential change of the SCME category, and MBO grade. RESULTS: Factors independently associated with poor MBO were incomplete IAR (OR=14.94, 95%CI: 2.46, 289.21, P=0.002) and a history of SCME (OR=4.13, 95% CI: 1.05, 18.65, P=0.043). The MBO grade strongly correlated with the IAR class (correlation coefficient [r]=0.84, P<0.0001). MBO grade correlated with sequential change of the SCME category (r=0.56, P<0.0001). The sequential change of the SCME category correlated with IAR class (r=0.53, P<0.0001). CONCLUSION: Although IAR and its class were strong long-term predictive factors of MBO, a history of SCME and upgrading of sequential change of SCME category were also long-term predictive factors of the MBO of bare platinum coiled intracranial aneurysms.

Concurrent cervical dural and multiple perimedullary arteriovenous fistulas presenting with subarachnoid hemorrhage: The source of bleeding was invisible at initial angiography.

BACKGROUND: We report the concurrence of a spinal dural arteriovenous fistula (DAVF) and multiple perimedullary arteriovenous fistulas (PAVFs) presenting with subarachnoid hemorrhage (SAH). Moreover, the bleeding site was detected 1 month after onset. CASE DESCRIPTION: A 56-year-old man was admitted to our hospital with an SAH. A DAVF and two PAVFs were detected at the C2 level by two rounds of digital subtraction angiography. The source of bleeding, an aneurysm on the feeding artery of PAVF, was detected at the second angiogram, which was performed 1 month after the onset of SAH. The aneurysm was not demonstrated at initial angiogram because of thrombosis in the aneurysm. The DAVF was interrupted by transarterial embolization, and the two PAVFs were subsequently treated with surgery. CONCLUSION: A part of the whole AVFs or the source of bleeding may be invisible in the acute stage just after hemorrhage. Repeated angiography is necessary to diagnose such complex AVFs especially in case of an SAH and treatment should be performed during the subacute stage.

Delayed asymptomatic coil migrations toward different arteries after aneurysmal embolization: case report.

Delayed coil migration after endovascular treatment with detachable coils, particularly several months after treatment, is extremely rare. In this report, the authors describe a 77-year-old female in whom delayed coil migration to the anterior cerebral artery and posterior communicating artery (PCoA) developed 3 months after an uncomplicated aneurysm embolization. The patient was successfully retreated with a closed-cell stent. Computational fluid dynamics (CFD) revealed high wall shear stress (WSS) and multiple vortices in the residual cavity of the initially treated aneurysm. CFD could be useful to detect and predict this complication, and a stent-assisted technique could be an important treatment option.

Intraoperative Rupture of Unruptured Cerebral Aneurysm during Craniotomy: A Case Report.

An unruptured aneurysm was incidentally found in the right middle cerebral artery in a 67-year-old woman. During an attempt to turn the temporalis muscle for surgical clipping, systolic blood pressure suddenly increased. After opening the dura mater, we found a subarachnoid hemorrhage and severe brain swelling. We promptly expanded the craniotomy area to reach the aneurysm while pulling part of the frontal lobe to apply a clip. We retrospectively analyzed the aneurysm using computational fluid dynamics. Our analysis suggests that the rupture of the aneurysm occurred at a location with very low wall shear stress.

Unique Venous Drainage of a Sphenoid Wing Dural Arteriovenous Fistula with Ocular Symptoms.

BACKGROUND: Dural arteriovenous fistulas (DAVFs) presenting with ocular symptoms, such as exophthalmos and chemosis, are commonly situated in the cavernous sinus (CS). DAVFs at the sphenoid wing with a drainage route into the superior orbital vein (SOV) should be considered as one of the differential diagnoses of ocular symptoms. CASE DESCRIPTION: A 41-year-old woman presented with progressive left-sided chemosis and proptosis after left pulsating tinnitus that disappeared spontaneously. Cerebral angiography showed that the fistula was situated along the inferior edge of the superior orbital fissure on the greater sphenoid wing and drained solely into the SOV without flowing into the CS that caused ocular symptoms. Transvenous selective catheterization was performed via the facial vein and SOV. The fistula was then embolized using detachable coils. CONCLUSIONS: After embolization, the ocular symptoms resolved, and the patient was discharged without neurologic deficit. Herein, we discuss the developmental mechanism of the unique drainage pattern, including the clinical symptoms and anatomic features of greater sphenoid wing DAVFs.

Intracranial aneurysm formation after radiotherapy for medulloblastoma.

BACKGROUND: The development of an intracranial aneurysm after radiotherapy is rare but secondary effect of cranial irradiation in a primary disease treatment. CASE DESCRIPTION: The patient was a 17-year-old male adolescent who was diagnosed as having a posterior fossa medulloblastoma when he was 8 years old. He had undergone tumor resection with radiotherapy and chemotherapy. A distal posterior inferior cerebellar artery aneurysm was identified by magnetic resonance imaging 8 years after radiotherapy and grew rapidly throughout the next 1 year. The patient underwent microsurgical clipping and was discharged without deficit. CONCLUSION: This experience demonstrates that physicians caring for patients who have undergone intracranial radiotherapy should carefully consider the possibility of an aneurysmal formation when conducting follow-up imaging.

Treatment Result in the Initial Stage of Kanazawa Mobile Embolectomy Team for Acute Ischemic Stroke.

Five recent multicenter randomized controlled trials (RCTs) have clearly shown the superiority of mechanical thrombectomy in large vessel occlusion acute ischemic stroke compared to systemic thrombolysis. Although 14 hospitals in Ishikawa prefecture have uninterrupted availability of systemic thrombolysis, mechanical thrombectomy is not available at all of these hospitals. Therefore, we established a Kanazawa mobile embolectomy team (KMET), which could travel to these hospitals and perform the acute reperfusion therapy. In this article, we report early treatment outcomes and validate the effectiveness of a network between affiliated hospitals and KMET. Between January 2014 and December 2015, 48 patients, aged 45-92 years (mean: 73.0 years), underwent acute reperfusion therapy provided by KMET in 10 affiliated hospitals of Kanazawa University Hospital. The pre-treatment NIHSS scores ranged from 5 to 39 (mean: 19.1). ASPECTS+W ranged from 1 to 11 (mean: 7.3). Successful revascularization, defined as thrombolysis in cerebral infarction (TICI) 2b or 3, was achieved in 38/48 cases (80%), and a good outcome, defined as modified Rankin Scale (mRS) score from 0 to 2 at 90 days after the treatment, was achieved in 24/48 cases (50%). There were two cases of intracranial bleeding (4%). Mean time from onset to recanalization was 297 min. These results, which are similar to those of five previous RCTs, suggest that a collaborative network between affiliated hospitals and KMET is effective for acute reperfusion therapy in local areas wherein experienced neuroendovascular specialists are insufficient.

Pseudoaneurysm formation caused by the withdrawal of a Trevo ProVue stent at a tortuous cerebral vessel: a case report.

This is the first report on the mechanism of pseudoaneurysm formation after withdrawal of a stent retriever. A 79-year-old woman developed cardiogenic embolization of the distal middle cerebral artery (M2). The deployed stent retriever bent because of vessel tortuosity. After withdrawal of the stent with strong resistance, complete revascularization was achieved, but an extravasation was detected at the site. Eight hours after disappearance of the extravasation, re-bleeding occurred with aneurysm-like pooling of contrast media. Direct surgical observation confirmed a pseudoaneurysm formation. The pseudoaneurysm was likely formed by avulsion of a fine vessel during withdrawal of the stent retriever at a tortuous vessel.