[Preoperative Embolization for Organized Hematoma of the Maxillary Sinus with Low-concentration n-butyl-2-cyanoacrylate:A Case Report].

Organized hematoma is a rare, non-neoplastic, and hemorrhage-prone condition that requires attention due to the risk of intraoperative bleeding. Preoperative embolization was performed to ensure intraoperative hemorrhage control. Here, we report a case of preoperative embolization of an organized hematoma using a low-concentration of n-butyl-2-cyanoacrylate(NBCA). An 80-year-old male presented with a 2-month history of repeated nasal bleeding and nasal obstruction. Diagnostic imaging revealed a mass measuring 3.7 cm in the right maxillary sinus with thinning of the surrounding bone. This was diagnosed as an organized hematoma with a biopsy. As a preoperative treatment, embolization of the main feeding artery was performed through the external carotid artery, using a low concentration of NBCA(5%). When the NBCA cast had reached the organized hematoma, as observed on plain CT, endoscopic sinus surgery was performed, and the organized hematoma was resected without significant bleeding. Preoperative embolization of the organized hematoma with low-concentration NBCA was useful to prevent heavy intraoperative bleeding.

Angiogenesis in the Septum and Inner Membrane of Refractory Chronic Subdural Hematomas: Consideration of Findings after Middle Meningeal Artery Embolization with Low-concentration n-butyl-2-cyanoacrylate.

The middle meningeal artery (MMA) is suggested to play an important role in the recurrence of chronic subdural hematomas (CSDHs). However, the exact mechanisms involved in the recurrence of CSDHs still remain unknown. For recurring CSDHs, MMA embolization is performed using low-concentration n-butyl-2-cyanoacrylate (NBCA) at our hospital. We report new findings and a discussion related to the mechanism of CSDH recurrence based on the imaging findings after MMA embolization, and cases that required craniotomy due to recurrence. The study included eight patients with recurrent CSDH, defined as ipsilateral hematoma re-enlargement within 3 months, and treated with MMA embolization. MMA embolization was performed successfully in all eight patients with no complications. Of the eight patients treated, one patient required craniotomy for the evacuation of CSDHs due to hematoma re-enlargement. NBCA casts were observed in the inner membrane of CSDHs in five of the eight patients by postoperative computed tomography scans. In the case that required craniotomy, the formation of neovasculatures was observed in the inner membrane of the CSDH. Our results suggested that angiogenesis also occurs in the septum and inner membrane through the MMA and the outer membrane of the CSDH. Additionally, these neovascular vessels may be involved in the recurrence of CSDH after MMA embolization. In a future larger study, it is necessary to elucidate in detail the vascular architecture of the CSDH membrane associated with the hematoma re-enlargement, and the effectiveness of MMA embolization that embolized to these peripheral neovascular vessels.

Impact of Right-Sided Aneurysm, Rupture Status, and Size of Aneurysm on Perforator Infarction Following Microsurgical Clipping of Posterior Communicating Artery Aneurysms with a Distal Transsylvian Approach.

BACKGROUND: Posterior communicating artery (PCoA) aneurysms are among the most common aneurysms. Because blockage of the PCoA and perforators can cause adverse outcomes, occlusion of these arteries by surgical clipping should be avoided. The impact of factors on PCoA perforator infarction when using a distal transsylvian approach for PCoA aneurysms was examined. METHODS: A total of 183 patients underwent PCoA aneurysm clipping, excluding application of fenestrated clips. Patients were divided into 2 groups: patients with PCoA perforator infarction (infarction group) and patients without infarction (noninfarction group). Multiple factors were analyzed in the 2 groups. RESULTS: Twenty-two of the 183 patients (12.0%) showed perforator infarction, mainly on magnetic resonance imaging evaluation, resulting in permanent deficits in 2 patients (1.1%). The proportion of right-sided operations (86.4% vs. 53.4%; P = 0.005) and surgery for rupture (90.9% vs. 55.9%; P = 0.002) were significantly higher in the infarction group than in the noninfarction group. Aneurysms were significantly larger in the infarction group (8.4 ± 3.8 mm) than in the noninfarction group (6.3 ± 3.0 mm; P = 0.02). Ruptured status (odds ratio [OR], 7.35; P = 0.01), right side (OR, 5.19; P = 0.01), and aneurysm size (OR, 1.18; P = 0.02) remained independent predictors of perforator infarction on multivariate logistic regression analysis. CONCLUSIONS: Ruptured status, right side, and large PCoA aneurysm were independent predictors of PCoA perforator infarction. Symptoms due to PCoA perforating infarction were mostly transient and rarely affected outcomes.

Efficacy of Cone Beam Computed Tomography in Treating Cavernous Sinus Dural Arteriovenous Fistula.

BACKGROUND: Exact identification of feeding arteries, shunt points, and draining veins is essential in treating cavernous sinus dural arteriovenous fistula (CS dAVF). In addition to digital subtraction angiography (DSA) and 3-dimensional rotational angiography (3DRA), high-resolution cone beam computed tomography (CBCT; especially 80-kv high-resolution cone beam computed tomography) have been performed in recent years. We evaluated the efficacy of CBCT in treating CS dAVF. METHODS: Eight CS dAVFs were treated with endovascular embolization between January 2013 and December 2016. We retrospectively examined these cases regarding information from DSA, 3DRA, and CBCT with contrast medium. RESULTS: Although all procedures can evaluate feeding arteries, shunt points, and draining veins, CBCT can provide the best definition of feeders and their course through the bony structures and the compartment of CS. Therefore, CBCT with placed microcatheter in the CS can reveal whether the microcatheter is set at the appropriate compartment to be embolized. CONCLUSIONS: The efficacy of CBCT in treating dAVF is illustrating the relationships among the bony structures and feeders, compartment of CS, and the position of the microcatheter. Detailed information obtained with CBCT can lead to fewer complications and more effective treatment.

Initially Missed or Delayed Diagnosis of Subarachnoid Hemorrhage: A Nationwide Survey of Contributing Factors and Outcomes in Japan.

BACKGROUND: Subarachnoid hemorrhage (SAH) remains a significant cause of mortality in Japan. The Japan Stroke Society set out to conduct a nationwide survey to identify contributing factors and outcomes of SAH misdiagnosis. METHODS: We initially surveyed 737 training institutes and 1259 departments in Japan between April 2012 and March 2014 for the presence of misdiagnosed SAH. Clinical information was then sought from respondents with a positive misdiagnosis. Information on 579 misdiagnosed cases was collected. RESULTS: Most initial misdiagnoses occurred in nonteaching hospitals (72%). Of those presenting with headache, 55% did not undergo a computed tomography (CT) scan. In addition, SAH was missed in the patients who underwent CT scans. The clinically diagnosed rerupture rate was 27%. Mortality among all cases was 11%. Institutes achieving a final diagnosis were staffed by neurologists or neurosurgeons. Multivariate logistic regression analysis indicated that age (≥65), consciousness level (Japan Coma Scale score at correct diagnosis), rerupture of an aneurysm, and no treatment by clipping or coiling were significantly associated with poor clinical outcome. CONCLUSIONS: The prognosis of misdiagnosis of SAH is severe. Neuroradiological assessment and correct diagnosis can prevent SAH misdiagnosis. When there is a possible diagnosis of SAH, consultation with a specialist is important.

Efficacy of high-resolution cone-beam CT in the evaluation of perforators in vertebral artery dissection.

Introduction A major complication of internal coil trapping for vertebral artery dissection (VAD) is medullary infarction associated with perforator occlusion. Currently, higher spatial resolution imaging can be obtained with high-resolution cone-beam computed tomography (VASO CT), and the efficacy of perforator visualization adjacent to VAD was examined. Methods Eight patients who underwent internal coil trapping or stent-supported coil embolization underwent VASO CT to evaluate perforators around VAD. Visualization of perforators was compared with conventional digital subtraction angiography (DSA) and three-dimensional rotational angiography (3D-RA). Postoperative MRI was performed in all patients to investigate ischemic complications. The relationship between the perforators and the infarction was analyzed. Results Perforator visualization was much clearer on VASO CT than on 2D DSA or 3D-RA. It was sharp enough to identify each perforating artery. Medullary infarctions were detected in two cases. In these two cases, each ischemic lesion corresponded to the territory of a perforator that was well visualized on VASO CT. The axial view with adjoining tissue structures on VASO CT was useful to detect the territories of perforators. Conclusions VASO CT is an efficient modality for the detection and identification of perforators in the vicinity of VAD. It provides accurate anatomical information about the vertebrobasilar system that is useful for the treatment of unruptured VAD.

Delayed Normalization of Electrocardiograms in Patients with Takotsubo Cardiomyopathy due to Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Takotsubo cardiomyopathy (TCM) is caused by excessive physical and mental stress, and sometimes causes potentially fatal arrhythmias such as torsades de pointes. This study characterized the features of TCM due to aneurysmal subarachnoid hemorrhage, particularly the delayed normalization of electrocardiograms compared with that of transthoracic echocardiograms. METHODS: Ten patients with TCM were selected from the 450 patients with subarachnoid hemorrhage treated in our hospital between January 2007 and November 2015. We retrospectively examined these 10 patients with regard to various factors, including durations of abnormal electrocardiographic and echocardiographic findings. RESULTS: All 10 patients were women. Mean age at diagnosis was 69.3 years (range, 40-90 years). Electrocardiographic findings were as follows: inverted or flattened T waves (100%); QTc prolongation >0.45 seconds (90.0%); ST segment elevation (60.0%); and ST segment depression (20.0%). Echocardiograms showed typical findings of TCM in 9 cases and inverted TCM in 1 case. In 1 case, ventral fibrillation was observed. Normalization of electrocardiograms was consistently delayed compared with that of echocardiograms, by more than 3 weeks in at least 5 cases (50%). If follow-up of electrocardiographic parameters is discontinued at the point of normalization of wall motion and the end of the vasospasm period, fatal arrhythmia may occur in the aftermath. CONCLUSIONS: This study showed a notable delay in recovery of abnormal electrocardiographic findings compared with the recovery of echocardiographic findings. Sufficient attention to persistent abnormalities on electrocardiography is warranted, even after improvements in cardiac wall motion and the vasospasm period.

Histopathological Findings in Brains of Patients Who Died in the Acute Stage of Poor-grade Subarachnoid Hemorrhage.

Patients with poor-grade aneurysmal subarachnoid hemorrhage (SAH) are likely to die due to irreversible acute-stage primary brain damage. However, the mechanism(s) and pathology responsible for their high mortality rate remain unclear. We report our findings on the brains of individuals who died in the acute stage of SAH. An autopsy was performed on the brains of 11 SAH patients (World Federation of Neurosurgical Societies grade 5) who died within 3 days of admission and who did not receive respiratory assistance. All brains were free of intracranial hematoma and hydrocephalus; all harbored ruptured aneurysms. In all brains, multiple infarcts with perifocal edema were scattered throughout the cortex and subcortical white matter of the whole brain. Infarcts with a patchy - were more often seen than infarcts with a wedge-shaped pattern. Microscopic examination revealed multiple areas with cytotoxic edema and neuronal death indicative of acute ischemic changes. Edema and congestion were more obvious in areas where the subarachnoid clot tightly adhered to the pia mater. Pathologically, the brains of deceased patients with acute poor-grade SAH were characterized by edema and multifocal infarcts spread throughout the whole brain; they were thought to be attributable to venous ischemia. Diffuse disturbance in venous drainage attributable to an abrupt increase in the intracranial pressure and focal disturbances due to tight adhesion of the subarachnoid clot to the pia mater, may contribute strongly to irreversible brain damage in the acute stage of SAH.

Subarachnoid hemorrhage from dissecting aneurysm of the posterior communicating artery.

A 36-year-old woman on chronic hemodialysis presented with sudden onset of headache and deterioration of consciousness. She was sent to our hospital on day 1, with subarachnoid hemorrhage. Cerebral angiography showed pearl and string sign on the left posterior communicating artery, which was consistent with a diagnosis of hemorrhage from a dissecting aneurysm of the left posterior communicating artery. She underwent parent artery occlusion via endovascular treatment on day 2. Although cone beam computed tomography before embolization showed a perforator from the lesion, there were no ischemic lesions on diffusion-weighted imaging after the procedure. She was discharged without any neurological deficits. It is important to recognize that dissecting aneurysm of the posterior communicating artery is one cause of subarachnoid hemorrhage. We also discuss the utility of cone beam computed tomography in formulating the treatment plan for such patients.

Efficacy of high-resolution cone-beam CT in the evaluation of carotid atheromatous plaque.

INTRODUCTION: A major disadvantage of carotid artery stenting (CAS) is the high incidence of perioperative cerebral embolism. Cerebral embolism after CAS is associated with soft plaque. Currently, higher spatial resolution imaging can be obtained with cone-beam CT (CB-CT). The correlation between the degree of contrast enhancement of the vasa vasorum (VV) on CB-CT and the vulnerability of plaque in terms of risk factors for CAS was evaluated. METHODS: 18 patients who underwent CAS had high-resolution CB-CT to evaluate enhancement of the VV covering carotid plaque performed intraoperatively. The appearance of the surface of the carotid plaque was classified as either enhancing (VV-positive) or non-enhancing (VV-negative). Carotid plaque vulnerability on black-blood MRI (BB-MRI) and postoperative ipsilateral ischemic lesions on diffusion-weighted imaging (DWI) were analyzed in the two groups. RESULTS: Of the 18 patients, 9 were VV-positive and 9 were VV-negative. The proportion of ipsilateral new ischemic lesions on DWI was significantly higher in the VV-positive group than in the VV-negative group (8/9 patients (88.9%) vs 3/9 patients (33.3%), p=0.026). BB-MRI was performed preoperatively in 15 of 18 patients. The proportion of unstable plaque on BB-MRI was significantly higher in the VV-positive group than in the VV-negative group (9/9 patients (100%) vs 1/6 patients (16.7%), p=0.002). CONCLUSIONS: Enhancement of the VV covering carotid plaque on high-resolution CB-CT was significantly associated with unstable plaque on BB-MRI and postoperative ipsilateral new ischemic lesions.

Venous-Preserving Sylvian Dissection.

OBJECTIVE: The Sylvian fissure has been dissected through the frontal side of the superficial Sylvian veins with sacrifice of the tributaries of the frontal superficial Sylvian vein, which may lead to venous infarction. In addition, disturbed venous drainage makes the brain susceptible to brain retraction. Therefore, preservation of the vein is essential in modern neurosurgery to decrease morbidity. METHODS: We describe the technical nuances of Sylvian dissection with an emphasis on preserving the veins. RESULTS: The arachnoid between the frontal and temporal superficial Sylvian veins is divided as to enter the fissure. After the deep part in the Sylvian fissure is reached, the inside of the fissure is dissected along the "microvascular Sylvian fissure," the temporal side of the frontal vessels or the frontal side of the temporal vessels. The Sylvian fissure is dissected in a deep-to-superficial and posterior-to-anterior fashion ("paperknife technique") up to the skull base. The frontal superficial Sylvian vein usually tethers the brain to the dura, restricting the surgical corridor when approaching deep lesions. Peeling off the arachnoid that wraps this vein ("denude technique") allows the vein to stretch. CONCLUSIONS: Keeping the proper dissection plane ("microvascular Sylvian fissure") is crucial to preserve the veins. The "paperknife technique" makes the division of the frontal and temporal lobe easier. The "denude technique" provides a wider space between the frontal lobe and the skull base. These techniques make it possible to obtain a sufficiently wide surgical corridor to the basal cistern without sacrificing the veins and their tributaries.

Role of bypass surgery and balloon occlusion test for the endovascular management of fusiform dissecting aneurysms. Report of two cases.

Fusiform intracranial aneurysm is one of the most difficult pathologies to treat. The role and efficacy of recent advanced endovascular technique and conventional bypass surgery are discussed.

Takotsubo cardiomyopathy following subarachnoid haemorrhage.

A 67-year-old woman was admitted with aneurysmal subarachnoid haemorrhage and a 12-lead ECG showed ST segment elevation. Transthoracic echocardiography confirmed akinesis of the left ventricular mid-apical segment, with an ejection fraction of 26%, features characteristic of takotsubo cardiomyopathy. Five days later, we identified thrombus in the apex of the left ventricle. Sixteen days after onset, the thrombus had disappeared and wall motion improved (ejection fraction 58%) without evidence of cardioembolism. Takotsubo cardiomyopathy is a cause of cardiac dysfunction after stroke, including SAH. It is characterised by transiently depressed contractile function of the left mid and apical ventricle, without obstructive coronary artery disease. Clinicians should suspect takotsubo cardiomyopathy in patients with subarachnoid haemorrhage who have an ECG abnormality. Echocardiography is needed to detect the distinctive regional wall motion abnormality. Despite its severity in the acute phase, takotsubo cardiomyopathy is self-limiting and its management is conservative.

Cosmetic frontotemporal craniotomy using an osteotome: technical note.

A frontotemporal craniotomy is usually performed using a "keyhole," made at the union of the zygomatic arch and frontal bone. Consequently, skull depression may occur postoperatively, leading to temporal area deformities and poor cosmetic results. To prevent these complications, we describe our technique for frontotemporal craniotomy using an osteotome to prevent cosmetic deformities. After the temporal muscle is dissected and reflected with the scalp flap, a total of 3 burr holes are made in the frontal and temporal bones. In the lateral greater wing of the sphenoid, where a keyhole is usually made, a bone incision is made anteriorly-posteriorly with an osteotome. The bone flap is lifted upward, and the osteotome is inserted from behind to continue the incision. At craniotomy closure, the bone flap is fixed using a cranial bone flap fixation clamp. This procedure involves almost no removal of frontal or inferior temporal bone, resulting in virtually no bone defect. The absence of skull depression or deformity in the temples postoperatively leads to excellent cosmetic results. Our technique for frontotemporal craniotomy using an osteotome does not create bone defects, and use of titanium clamps for bone flap fixation provides normal skull bone alignment. This procedure provides excellent postoperative cosmetic results.

Middle meningeal artery aneurysm associated with meningioma.

Middle meningeal artery aneurysm associated with meningioma is extremely rare, and only two cases have previously been reported. In our case, a 72-year-old woman with convexity meningioma underwent preoperative cerebral angiography, which revealed a flow-related aneurysm on the middle meningeal artery. Embolization of the aneurysm was performed with N-butycyanoacrylate glue, and complete obliteration was confirmed under craniotomy. In order to eliminate the risk of preoperative rupture resulting in intracranial hemorrhage, endovascular embolization with liquid glue is safe and effective for this kind of aneurysm.

Post-operative changes of cerebral circulation and metabolism in the acute stage of low-grade aneurysmal subarachnoid hemorrhage.

OBJECTIVE: Pre- and post-operative cerebral circulation and metabolism were evaluated in patients with low-grade acute aneurysmal subarachnoid hemorrhage (SAH) who underwent early surgery to investigate the effects on brain dysfunction. METHODS: Positron emission tomography (PET) was performed to measure the regional cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), oxygen extraction fraction (OEF) and cerebral blood volume in four patients (one male and three females, mean age: 60.3 years) with low-grade SAH within 30 hours of onset. Post-operative PET was performed on the seventh post-operative day. No patient suffered clinical deterioration during the study. Pre-operative PET scans demonstrated significant global reduction of CBF and CMRO2, compared to 16 normal control subjects, and no significant change in OEF. CBF and CMRO2 reduction post-operatively improved to the normal control values. Post-operative OEF was significantly increased compared to the normal control value. CONCLUSIONS: Patients with low-grade SAH have impairment of cerebral circulation and metabolism in the acute period, which improves after surgery. Early surgery for low-grade SAH, necessary to avoid rerupture of the aneurysm, did not worsen the impairment of cerebral circulation and metabolism. However, measures to protect the brain from perioperative damage are necessary to achieve the optimum outcome.

Carotid artery resection: preoperative temporary occlusion is not always an accurate predictor of collateral blood flow.

CONCLUSION: The morbidity predicted by means of preoperative PET studies does not always correlate with the morbidity experienced after permanent carotid artery occlusion. A pre-resection extracranial-intracranial bypass may be necessary to reduce the risk of neurologic morbidity, in particular when carotid artery resection is planned for tumors involving the skull base. OBJECTIVES: Carotid artery resection is generally considered the only curative treatment for patients with advanced head and neck carcinoma involving the carotid artery. PET can be used during temporary occlusion of the internal carotid artery to assess the safety of the procedure. The aims of this paper were to clarify the risk of carotid artery resection and the benefit of extracranial-intracranial bypass. MATERIAL AND METHODS: Twelve patients diagnosed with head and neck cancer adherent to the carotid artery and in proximity to the skull base who had shown good hemispheric collateral blood flow by means of PET underwent carotid artery resection without preoperative bypass. RESULTS: Of the 12 patients who underwent carotid artery resection without reconstruction, 10 suffered no serious neurologic complications; however, 2 suffered cerebral infarctions intraoperatively.

Morbidity and mortality from surgical treatment of unruptured cerebral aneurysms at Research Institute for Brain and Blood Vessels-Akita.

OBJECTIVE: Although the necessity of craniotomy for an unruptured cerebral aneurysm (UCA) is controversial, surgery is warranted if surgical risks are less than the risks of natural history. In this study, we investigated the need for craniotomy for UCAs on the basis of surgical risk. METHODS: History of cerebrovascular disorders, aneurysm site and size, surgical complications, and clinical outcome were investigated in 368 patients (134 men, 234 women; ages 31-79 yr) who underwent craniotomy for treatment of UCA at our institute between 1993 and 2000. RESULTS: We investigated 549 aneurysms. The mean size was 6.0 mm. Sites affected were the anterior cerebral artery (101 aneurysms), internal carotid artery (224 aneurysms), middle cerebral artery (201 aneurysms), and vertebrobasilar artery (23 aneurysms). The most common previous cerebrovascular disorders were subarachnoid hemorrhage (58 patients, 15.8%) and cerebral infarction (41 patients, 11.1%). Eight patients experienced permanent neurological deficits, for a total morbidity of 2.2%. One patient died, for a total mortality of 0.3%. For UCAs less than 10 mm in size, the morbidity was 0.6% and the mortality was 0%. For UCAs greater than 10 mm in size, the morbidity was 6.1% and the mortality was 1.2%. For UCAs in the anterior cerebral artery or middle cerebral artery, the morbidity was 0.3%. Temporary deficits were more frequently observed in patients older than 70 years of age than in patients 70 years of age or less. CONCLUSION: Surgical treatment is a viable alternative for patients 70 years of age or less with UCAs less than 10 mm in size or UCAs located in the anterior cerebral artery or middle cerebral artery, because the surgical risk of treating such UCAs is sufficiently lower than the annual rupture rate of UCAs (2.3%) and the mental stress suffered by patients with untreated UCAs.

Incidence and risk factors for the growth of unruptured cerebral aneurysms: observation using serial computerized tomography angiography.

OBJECT: The goal of this study was to examine the growth of unruptured intracranial aneurysms with the focus on the risk factors and incidence of these lesions. METHODS: One hundred sixty-six untreated cerebral saccular aneurysms were analyzed in 140 patients. The age of the patients ranged from 29 to 82 years (mean 62.8 years), the female/male ratio was 94:46, and the mean follow-up period was 17.7 months. Aneurysms were located at the internal carotid artery (ICA) in 68 patients, the middle cerebral artery (MCA) in 43, the anterior cerebral artery in 38, the basilar artery (BA) in 13, and the vertebral artery in four patients. The maximum diameter of the lesions ranged from 2 to 20 mm (mean 4.1 mm). All patients were examined using serial computerized tomography angiography to evaluate signs of aneurysm growth. Although growth was identified in 10 aneurysms (nine patients 16.4%]), no bleeding occurred. Growth-related changes were significantly associated with the size of the aneurysm and occurred in three (2.4%) of 125 aneurysms measuring 2 to 4 mm, three (9.1%) of 33 lesions measuring 5 to 9 mm, and four (50%) of eight lesions measuring 10 to 20 mm. These changes were more frequently found in aneurysms located at the BA bifurcation (two [40%] of five lesions) and the ICA (six [8.8%] of 68 lesions) than in those located at the MCA (zero of 43 lesions, p < 0.05). The 1-, 2-, and 3-year cumulative growth rates calculated using the Kaplan-Meier method were 2.5, 8, and 17.6%, respectively. CONCLUSIONS: A diameter of at least 10 mm and a location at the BA bifurcation or the ICA were significant risk factors for aneurysm growth. The incidence of growth was 2.5% in the 1st year and this risk increased yearly. Computerized tomography angiography is useful for follow up of patients with aneurysms because it allows the detection of even subtle morphological changes.