Morphological Classification of the Medial Frontal Cortex Based on Cadaver Dissections: A Guide for Interhemispheric Approach.

The medial frontal cortex (MFC) is a part of the medial surface of the frontal lobe situated in the rostral portion of the corpus callosum (CC). In a surgical interhemispheric approach (IHA), the MFC covers the anterior communicating artery (Aco) complex until the final stage of dissection. To clarify the anatomical relationship between the MFC and the Aco complex, and to facilitate orientation in IHA, we analyzed the morphological features of the MFC in number, size, and pattern of gyri from the medial surface of the hemisphere in the subcallosal portion using 53 adult cadaveric hemispheres. The mean width of the MFC excluding cingulate gyrus (MFCexcg) was 20.6 ± as mm in the subcallosal portion. MFCexcg consisting of 2, 3, 4, or 5 gyri were observed in 7.5%, 56.6%, 32.1%, or 3.8% of the hemispheres, respectively. Bilateral MFCexcg consisting of >2 gyri were observed in approximately 85% of the hemispheres. Therefore, in many cases, the dissection performed at 2 cm upward from the base of the straight gyrus (SG) or 3-4 gyri of the MFC is sufficient to safely reach the upper portion of the cistern of lamina terminalis located distal to the Aco complex in IHA. The MFC is a good landmark for intraoperative orientation in IHA.

Stenting for Innominate Artery Stenosis Under Double-Filter Protection of the Anterior and Posterior Circulation via the Right Brachial Artery.

Several protocols for angioplasty and stenting for stenosis of an innominate artery (IA) are reported, but the protocols are sometimes complicated and have disadvantages. We report a case of IA stenosis presenting ischemic symptoms in a 58-year-old woman. Stenting for the IA stenosis was performed through the right femoral artery. The cerebral protection was placed via the right brachial artery, with a filter at the right internal carotid artery and another filter at the right vertebral artery. The symptomatic IA stenosis was resolved without any complications. Regardless of the direction of blood flow, simultaneous protection of both the anterior and posterior cerebral circulation is necessary during IA stenting. Double-filter protection can provide excellent cerebral protection during an IA stenting procedure.

Morphological Pattern and Classification of the Superficial Middle Cerebral Vein by Cadaver Dissections: An Embryological Viewpoint.

In this study, we used 45 adult cadaveric cerebral hemispheres to investigate the anatomical classification of the superficial middle cerebral vein (SMCV) based on the number of stems, course, and anastomosis at the distal portion. We classified the SMCVs into five types based on embryological concept. Type A (18 cases, 40.0%) is that the frontosylvian veins (FSVs) merge with the vein of Trolard (VT) and the vein of Labbé (VL) at the distal portion of the sylvian fissure. Type B (5 cases, 11.1%) is that the temporosylvian veins (TSVs) merge with the VT and the VL at the distal portion. Type C (13 cases, 28.9%) is that no vein merge with the VT and the VL at the distal portion. The VT merges with the SMCV from the FSV and the VL merges with the SMCV from the TSV. They course along the sylvian fissure and merge at the proximal portion. In Type D (eight cases: 17.8%), the VT and the VL merge at the distal portion, and the SMCV from the FSV and the SMCV from the TSV join their confluence without merging. Type E (one case, 2.2%) show an undeveloped SMCV. Formation rate of intravenous anastomoses or bridging veins(BVs) at the distal portion between the frontosylvian trunk (FST) and the temporosylvian trunk (TST), between the FST and the temporal lobe, and between the TST and the frontal lobe was very low, because these formation may be difficult to occur during the embryological process in which the SMCV is formed from the telencephalic vein.

Endovascular Coil Embolization with Low-Profile Visualized Intraluminal Support Junior Stent for Ruptured Dissecting Aneurysm of Proximal Superior Cerebellar Artery-Case Report and Literature Review.

BACKGROUND: Superior cerebellar artery (SCA) aneurysm arising from the SCA itself is rare, and treatment of this aneurysm is challenging because of the important anatomic structures, such as the perforating arteries to the brainstem and cranial nerves. We describe a successful coil embolization with a Low-profile Visualized Intraluminal Support Junior (LVIS Jr.) stent for the proximal SCA dissecting aneurysm. CASE DESCRIPTION: A 50-year-old woman presented with right oculomotor nerve palsy and subarachnoid hemorrhage. Cerebral angiography showed a dissecting wide neck aneurysm at the anterior pontomesencephalic segment of the right SCA (diameter 1 mm). The patient was treated with coiling assisted by an LVIS Jr. stent. Postoperative angiography demonstrated a complete embolized aneurysm and parent artery preservation. CONCLUSIONS: Endovascular treatment assisted with LVIS Jr. stent for proximal SCA dissecting aneurysm arising from small parent artery was safely and effectively feasible.

[Treatment of a Traumatic Direct Carotid Cavernous Fistula with an Intradural Internal Carotid Artery Pseudoaneurysm Using a Low-profile Visualized Intraluminal Support(LVIS)Stent:A Case Report].

Traumatic carotid cavernous fistula(CCF)is known to present a direct connection between the cavernous segment of the internal carotid artery(ICA)and the cavernous sinus(CS). In rare cases, the fistula is formed between the intradural internal carotid artery(ICA)and the cavernous sinus(CS)via a pseudoaneurysm(pAN), requiring appropriate management and aggressive surgical treatment. We describe a 58-year-old man who sustained a severe head injury diagnosed as traumatic CCF treated with an intradural pAN procedure and transarterial coil embolization combined with a Low-profile Visualized Intraluminal Support(LVIS)stent. While slow arteriovenous shunt flow persisted at the end of the surgery, the fistula was completely occluded on the digital subtraction angiography obtained 2 weeks after the procedure. It was suspected that the flow-diversion effect of the LVIS stent might have caused the curable progression of the fistula occlusion.

Factors Related to Frailty Associated with Clinical Deterioration After Meningioma Surgery in the Elderly.

BACKGROUND: Older patients are increasingly presenting for surgery with intracranial meningioma because of progress with diagnostic imaging and longer life expectancy. However, older patients have many problems, such as comorbidities and reduced physiological capacity reflected in the frailty index. This study examines the factors affecting clinical deterioration after surgery in older patients, particularly factors associated with frailty. METHODS: Two hundred sixty-five patients older than 65 years underwent surgical resection of meningioma at Hiroshima University and related hospitals between 2000 and 2016. Karnofsky Performance Status (KPS) scores before and after surgery were evaluated. Factors related to the deterioration of KPS were analyzed with multivariate logistic regression modeling, including body mass index and serum albumin. RESULTS: KPS score deteriorated compared with preoperative score in 56 patients at discharge and in 40 patients at 3 months later, and 2 patients died within 1 year after surgery. Multivariate logistic regression analysis in addition to preoperative body mass index and serum albumin indicated skull base tumor location (odds ratio [OR], 4.67; 95% confidence interval [CI], 2.02-10.8) and serum albumin (OR, 2.38; 95% CI, 1.06-5.34) were risk factors for deterioration of KPS score at discharge. Age (OR, 0.91; 95% CI, 0.85-0.98), skull base tumor location (OR, 4.32; 95% CI, 1.45-12.9), tumor size (OR, 1.03; 95% CI, 1.00-1.05), and serum albumin (OR, 3.53; 95% CI, 1.29-9.61) were significant risk factors for perioperative intracranial complications. CONCLUSIONS: Skull base tumor location and serum albumin correlated with deterioration of clinical status after surgery.

Importance of frailty evaluation in the prediction of the prognosis of patients with chronic subdural hematoma.

AIM: The present study aimed to clarify the relationship between frailty and prognosis of patients with chronic subdural hematoma. METHODS: This retrospective study involved 211 patients aged ≥65 years with chronic subdural hematoma, who underwent surgery at Higashihiroshima Medical Center, Hiroshima, Japan, between July 2011 and May 2017. The study outcome was the patient's modified Rankin Scale score at 3 months after surgery. A logistic regression analysis was carried out to analyze factors that influenced the outcome. RESULTS: Chronic subdural hematoma patients with frailty had a poorer prognosis than those without (median modified Rankin Scale: 4 and 2, P < 0.001; proportions of patients discharged to home: 35% and 91%, P < 0.001, respectively). After adjusting for patients' background, the patients' modified Rankin Scale scores at 3 months after surgery were found to be associated with age, controlling nutritional status score and recurrence, but not with frailty. However, receiver operating characteristic curves of the model with the Clinical Frailty Scale were more accurately correlated with prognosis than those of the model without this scale (area under the curve 0.98, 95% confidence interval 0.96-0.99; and 0.87, 95% confidence interval 0.82-0.91, respectively.) CONCLUSIONS: Chronic subdural hematoma patients with frailty had poorer prognosis than those without. The evaluation of the presence of frailty on admission can be an important factor in the prediction of the prognosis of chronic subdural hematoma patients. Geriatr Gerontol Int 2018; 18: 1173-1176.

The Effect of Irrigation Solutions on Recurrence of Chronic Subdural Hematoma: A Consecutive Cohort Study of 234 Patients.

Chronic subdural hematomas (CSDHs) occur often in elderly persons and can occur with mild head trauma. With burr-hole irrigation as standard treatment, symptoms usually improve and can be cured, and outcomes are good, but postoperative recurrences are a common problem. This study investigated the effectiveness and recurrence rates when using artificial cerebrospinal fluid (ACF) instead of normal saline (NS) as an irrigation solution for burr-hole irrigation in patients with CSDH. This prospective study included 234 consecutive patients who underwent initial surgical treatment by burr-hole irrigation for a CSDH between April 2008 and June 2015. The irrigation solution used was changed from NS to ACF in June 2011. Factors examined with regard to recurrence included age, sex, unilateral or bilateral surgery, computed tomography (CT) findings, antiplatelet or anticoagulant drug use, past history, and irrigation solution (NS or ACF). These were analyzed by univariate and multivariate analyses. Univariate analyses (chi-square test) with a significance level <5% showed that recurrence rates were significantly lower in the ACF group than in the NS group (P = 0.003). Multivariate analysis (multiple logistic regression analysis) showed that the risk of recurrence was reduced 3.14-fold in the ACF group compared to the NS group (odds ratio, 3.143; 95% confidence interval, 0.1504-0.6733; P = 0.0028). None of the other factors were significantly different. In burr-hole irrigation for CSDH, the use of ACF instead of NS as an irrigation solution significantly reduces recurrence rates.

Frequency and Predicting Factors on Chronic Expanding Intracerebral Hematoma in Spontaneous Intracerebral Hemorrhage.

BACKGROUND: Chronic expanding intracerebral hematoma is a well-known complication of spontaneous intracerebral hemorrhage. However, because chronic expanding intracerebral hematoma is relatively rare, it has not been studied systemically. The purpose of this study was to characterize a patient population with chronic expanding intracerebral hematoma, and to identify the predictive factors for it. METHODS: We retrospectively evaluated 112 patients with spontaneous putaminal hemorrhage who were treated at our institution between January 1, 2010 and December 31, 2015. Data on age, sex, Glasgow Coma Scale score, presence of intraventricular hemorrhage, and intracerebral hemorrhage volume were collected, and their predictive values for chronic expanding intracerebral hematoma were investigated. We also evaluated the predictive value of a characteristic radiological finding at onset called the "layer sign," which was represented as a fluid level adjacent to the clot. RESULTS: Chronic expanding intracerebral hematoma was observed in 4 patients (4.9%) with spontaneous intracerebral hemorrhage. Only the layer sign was significantly related to chronic expanding intracerebral hematoma (P = .003), and was found to be independently associated with chronic expanding intracerebral hematoma in a multivariate analysis (odds ratio, 18.6; 95% confidence interval, 1.19-291.0; P = .037). CONCLUSIONS: The frequency of chronic expanding intracerebral hematoma in those with spontaneous intracerebral hemorrhage was estimated at 4.9%. The layer sign was a useful factor for predicting chronic expanding intracerebral hematoma.

A Case of Holocord Leptomeningeal Dissemination from Cerebellar Hemangioblastoma without von Hippel-Lindau Disease.

Hemangioblastoma disseminated along leptomeninges from the solitary cranial lesion without von Hippel-Lindau (VHL) disease is a quite rare instance with 23 cases reported in 40 years. We add a new case and discuss these rare instances. A 55-year-old female underwent surgery for total removal of cerebellar hemangioblastoma. Twenty months later, magnetic resonance (MR) images of the spinal cord revealed a tumor compressing the thoracic cord at T3-4 level which was removed en bloc by emergent spinal surgery. However, paraplegia and bowel bladder dysfunction recurred 5 months after the spinal surgery. Spine MR images showed diffuse enhancement of subarachnoid space. Exploratory surgery disclosed that the enhanced lesion was disseminated hemangioblastoma. After whole spinal irradiation, she was transferred to a palliative care hospital. Even after complete removal, possibility of leptomeningeal dissemination demands continuous follow-up. The mechanism of seeding of hemangioblastoma remains unclear, but attention must be paid to avoid spreading tumor cells during surgery because all the disseminated cases had precedent cranial surgery.

Surgical resection of large encephalocele: a report of two cases and consideration of resectability based on developmental morphology.

INTRODUCTION: The first-line treatment of encephalocele is reduction of herniated structures. Large irreducible encephalocele entails resection of the lesion. In such case, it is essential to ascertain preoperatively if the herniated structure encloses critical venous drainage. CASE REPORTS: Two cases of encephalocele presenting with large occipital mass underwent magnetic resonance (MR) imaging. In first case, the skin mass enclosed the broad space containing cerebrospinal fluid and a part of occipital lobe and cerebellum. The second case had occipital mass harboring a large portion of cerebrum enclosing dilated ventricular space. Both cases had common venous anomalies such as split superior sagittal sinus and high-positioned torcular herophili. They underwent resection of encephalocele without subsequent venous congestion. We could explain the pattern of venous anomalies in encephalocele based on normal developmental theory. CONCLUSION: Developmental theory connotes that major dural sinuses cannot herniate into the sac of encephalocele. Irrespective to its size, encephalocele can be resected safely at the neck without subsequent venous congestion.

Isolated neurosarcoidosis presenting with multiple cranial nerve palsies.

BACKGROUND: As an extremely rare subtype of sarcoidosis that develops exclusively in the nervous system, isolated neurosarcoidosis is difficult to diagnose. In addition, its exact clinical features are not known. CASE DESCRIPTION: A 61-year-old man presented with right ear hearing loss, diplopia, and fever. Computed tomography (CT) and magnetic resonance imaging revealed mass lesions in the right cerebellum and left side body of the lateral ventricle. Neither systemic CT nor positron emission tomography revealed extracranial lesions. A neuroendoscopic biopsy was performed on the lateral ventricle lesion, and a histopathology analysis revealed epithelioid granulomatous inflammation. By systematic exclusion of other possible granulomatous diseases, isolated neurosarcoidosis was diagnosed. The lesions disappeared immediately upon corticosteroid (methylprednisolone) treatment and had not recurred as of a 12-month follow-up examination. CONCLUSIONS: Isolated neurosarcoidosis is difficult to diagnose. Successful diagnosis requires compatible clinical findings, histological demonstration of noncaseating granulomas, and exclusion of other granulomatous diseases. Isolated neurosarcoidosis has a relatively good clinical prognosis, which could be characteristic of the disease.

[Apixaban-Related Convexal Subarachnoid Hemorrhage:A Case Report].

The risk of anticoagulant-associated intracranial hemorrhage(ICH)is relatively low in patients treated with non-vitamin K antagonist oral anticoagulants(NOAC). The anticoagulant-associated ICH comprises mainly intraparenchimal hemorrhage. Subdural hematoma and subarachnoid hemorrhage(SAH)are rare complications after treatment with NOAC, trauma being the most common cause for these two types of ICH. We report a case of non-traumatic convexal SAH(cSAH)associated with Apixavan. A 68-year-old man with repeated history of cerebral embolism with cardiogenic cause presented with weakness of the lower limbs. Magnetic resonance imaging revealed infarctions, and treatment with apixaban(5 mg twice per day)was administered. Three days later, SAH in the right superior frontal sulcus was discovered incidentally on computed tomography(CT). NOAC-associated SAH is a rare manifestation. Cerebral amyloid angiopathy(CAA)is the most common cause of cSAH in the elderly, and cSAH is supposed to be a warning sign of cerebral hemorrhage in CAA. Patients with CAA started on NOAC require careful monitoring.

A Japanese pedigree of familial cerebral cavernous malformations--a case report.

Familial cerebral cavernous malformations (FCCM) are autosomal-dominant vascular malformations. At present, 3 cerebral cavernous malformation genes (KRIT1/CCM1, MGC4607/CCM2, and PDCD10/CCM3) have been identified. Few genetic analyses of Japanese FCCM have been reported. A Japanese pedigree of 4 patients with FCCM has been reported that includes the genetic analysis of one of the patients. All 4 patients showed multiple lesions in the brain. Surgical removal was performed at our hospital due to enlargement or hemorrhage of the intracranial lesions in a 21-year-old female (Case 1) and a 30-year-old male (Case 2). The histological diagnoses were cavernous malformations. A 62-year-old female (Case 4), the mother of Cases 1, 2, and 3, suffered from intramedullary hemorrhage at T6-7 and surgical removal was performed at another hospital. Only one patient, a 32-year-old female (Case 3), did not show symptoms. The genetic analysis of Case 2 demonstrated heterozygous partial deletions of exons 12-15 of the KRIT1 gene.

Differences between middle cerebral artery bifurcations with normal anatomy and those with aneurysms.

The objectives of this study were to elucidate the normal anatomy of middle cerebral artery (MCA) bifurcations and to analyze the differences in patients with MCA aneurysms. In the present study, 62 patients underwent three-dimensional magnetic resonance angiography, and no intracranial lesions were noted. The widths of M1 and the superior and inferior M2 branches, as well as their respective lateral angles, were measured. These values were used to calculate the daughter artery ratio (DA ratio; width of larger M2/width of smaller M2) and the lateral angle ratio (LA ratio; lateral angle between M1 and larger M2/lateral angle between M1 and smaller M2). The DA and LA ratios of 54 MCA aneurysm patients (34 with ruptured aneurysms, 20 with unruptured aneurysms) were also calculated, using three-dimensional digital subtraction angiography, and compared with the normal values. In normal patients, the widths of M1 and the branches of M2, the lateral angles, and the LA and DA ratios were not significantly different between the right and left sides. The bilateral superior and inferior lateral angles of normal MCAs were significantly wider than those of MCAs with aneurysms. The DA ratio was 1.5 ± 0.4 in normal MCAs and 1.7 ± 0.7 in MCAs with aneurysms; this difference was significant (p < 0.05). The LA ratio was 1.3 ± 0.4 in normal MCAs and 2.1 ± 1.4 in MCAs with aneurysms; these values were also significantly different (p < 0.01). Normal cerebral artery bifurcations show close to symmetric structure in the M2 branches and the lateral angles, whereas aneurysmal MCAs do not show this symmetry.

[Accessory nerve schwannoma of the intracisternal type: a case report].

Accessory nerve schwannomas are extremely rare and they are classified into three types according to their locations; intrajugular, intracisternal and spinal canal type. We report a case of intracisternal schwannoma that arose from the spinal accessory nerve roots and we describe it's clinical characteristics. A-48-year-old female was admitted to our hospital with a complaint of left occipital pain. Magnetic resonance imaging (MRI) showed a well-defined mass 2.5×1.5 cm in the left cerbellomedullary cistern. It was enhanced heterogeneously with gadolinium. Cerebral angiography showed a mildly hypervascular lesion. Total removal of the tumor was performed by the left lateral suboccipital approach and the histological diagnosis was schwannoma.

Morphological differences between ruptured and unruptured cases in middle cerebral artery aneurysms.

OBJECTIVE: To elucidate the morphological differences between ruptured and unruptured aneurysms, three-dimensional digital subtraction angiography was performed in 44 cases (20 unruptured, 24 ruptured) of middle cerebral artery aneurysm. METHODS: When the neck was located on the extension of the midline of the parent artery, it was defined as Type C; when it was not, it was defined as Type D. Aspect ratio (AP ratio; dome/neck ratio) and daughter artery ratio (DA ratio; diameter of the larger daughter artery/diameter of the smaller daughter artery) were calculated, and these ratios were compared for ruptured and unruptured cases. RESULTS: Nineteen cases were Type C and 25 cases were Type D. chi2 test revealed that there were significantly more ruptured cases among Type C (14 out of 19) compared with Type D (10 out of 25) (P < 0.05). AP ratios were 2.24 +/- 0.75 for ruptured cases and 1.56 +/- 0.58 for unruptured cases. DA ratios were 1.53 +/- 0.54 in ruptured cases and 2.14 +/- 0.80 for unruptured cases. Both showed significant differences (P < 0.01). In cases with an AP ratio of 1.8 or greater and a DA ratio less than 1.7, 13 out of 15 (87%) were ruptured cases. On the contrary, in cases with an AP ratio less than 1.8 and a DA ratio of 1.7 or greater, 12 out of 13 (92%) were unruptured cases. CONCLUSION: Type C and equality of the diameters of two daughter arteries, together with high AP ratios, seem to be morphological factors that associate with aneurysmal rupture.

The characteristics of the anterior communicating artery aneurysm complex by three-dimensional digital subtraction angiography.

To elucidate the three-dimensional structure of the anterior communicating artery complex, we performed three-dimensional digital subtraction angiography in anterior communicating (Acom) aneurysm cases. Eighteen patients (six male and 12 female) with Acom aneurysms were studied. The total number of aneurysms was 18, of which three were unruptured and 15 were ruptured. Aneurysmal sizes and angles between the parent artery and each of the two daughter arteries were measured. Two types were defined, based on the daughter arteries. When the sizes of the two daughter arteries were the same, they were defined as AA' type, and when different, they were defined as AB type. Furthermore, aneurysms were classified into two types based on neck location. Thus, when the neck was located on the extension of the midline of the parent artery, it was defined as classical neck type, and when it was not, it was defined as deviating neck type. There were 11 cases of AA' type and seven of AB type. In AA' type all cases were of the classical neck type, and in AB type three cases were of the classical neck type and three were of the deviating neck type. In the deviating neck type, the necks were deviated to the smaller daughter arteries in all cases.

Solitary brain metastasis from renal cell carcinoma 15 years after nephrectomy: case report.

A 77-year-old man presented with a metastatic brain tumor 15 years after nephrectomy for a renal cell carcinoma. Neurological examination showed recent memory disturbance and slight right hemiparesis. Magnetic resonance imaging revealed a round well-demarcated mass extending from the left thalamus to the left trigone of the lateral ventricle. Preoperative angiography showed tumor staining. Surgery was performed by opening the inferior temporal sulcus. Only biopsy could be performed because of extensive bleeding from the tumor. Histological examination identified metastatic renal cell carcinoma. Gamma knife surgery was performed which resulted in resolution of his hemiparesis. Metastatic renal cell carcinoma should be considered even if nephrectomy was performed 10 or more years before presentation.

Reconstruction of pterional key hole using three-dimensional titanium plate: technical note.

Patients who have undergone pterional craniotomy sometimes complain about postoperative cosmetic impairment in the frontotemporal area. This problem occurs as a result of inappropriate repair or no repair of the pterional key hole. The authors have developed an intraoperative hand-made three-dimensional titanium plate, and as a result of using this plate the postoperative cosmetic appearance was satisfactory.