Takashi Sadatomo

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

OBJECTIVETo 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. METHODSWhen 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. RESULTSNineteen cases were Type C and 25 cases were Type D. χ2 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. CONCLUSIONType 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.

Evaluation of relation among aneurysmal neck, parent artery, and daughter arteries in middle cerebral artery aneurysms, by three-dimensional digital subtraction angiography

Intracranial aneurysms usually occur at arterial bifurcations. However, in middle cerebral artery (MCA) aneurysms, we often find that the aneurysmal neck does not necessarily exist just on the arterial bifurcation. In this study, we have evaluated the relation among aneurysmal neck, parent artery, and daughter arteries in middle cerebral artery aneurysms, by three-dimensional digital subtraction angiography. Twenty consecutive patients (9 men and 11 women) with MCA aneurysms were examined. The total number of aneurysms was 22, of which 10 aneurysms were unruptured and 12 were ruptured. Aneurysmal sizes and angles between the parent artery and each of the two daughter arteries were measured. 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 a classical neck type aneurysm, and when it was not, it was defined as a deviating neck type aneurysm. There were 15 cases of deviating and 7 cases of classical neck type. Interestingly, in the deviating neck type, all the aneurysms existed on the side of the daughter arteries of which the angles between parent arteries were narrower, and in 93%, the sizes of the daughter arteries in which the neck existed were smaller compared with other daughter arteries.

Growth Inhibition of Human Glioma Cells by Transfection-induced P21 and its Effects on Telomerase Activity

The aim of this study is to investigate the effect of the p21 gene transfection on the growth of cultured human glioma cell lines, and analyze the telomerase activity, and detection of telomerase components in p21 transfectant.The p21 gene was transfected into human glioma cell lines, U251MG and T98G with our novel liposome. The cell growth was assessed by counting the number of trypan blue-excluding cells in a hemocytometer and flow cytometry analysis. The expression of P21 protein and its mRNA were examined by Western and Northern blot analysis. The telomerase activity was assayed by TRAP (telomerase repeat amplification protocol)/TRAP–HPA (hybridization protection assay) method qualitatively and quantitatively. The length of telomere was measured by Southern blot analysis. The expression of telomerase components (hTERT, hTERC and TEP1) were examined by RT-PCR (reverse transcriptase-polymerase chain reaction).The p21 transfectant demonstrated the expression of P21 protein and its mRNA. The p21 transfection of human glioma cells results in growth inhibition and G0/G1 arrest. The p21 transfectant revealed a decrease of telomerase activity and hTERT expression as compared with control cells.These results suggest that p21 transfection induces G0/G1 arrest in human glioma cells which associates with the reduction in the telomerase activity and hTERT expression.

Telomerase activity in central nervous system malignant lymphoma

Primary central nervous system malignant lymphoma (PCNSL) has been regarded as a rare neoplasm. Recently, however, its incidence has been rapidly increasing. Despite active clinical trials, its clinical and biologic features remain unknown and there has been no effective treatment or prognostic factor. The current study attempted to elucidate telomerase activity and expression of the telomere‐related RNA of PCNSL as novel prognostic factors.

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.

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.

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.

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.

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

IntroductionThe 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 reportsTwo 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.ConclusionDevelopmental 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.

[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.