44 research outputs found
Subtemporal approach to basilar tip aneurysm with division of posterior communicating artery: Technical note
The subtemporal approach with division of the posterior communicating artery (PcomA) is described for treating aneurysms of the basilar tip. When the ipsilateral posterior cerebral artery (PCA) interferes with visibility and manipulation around the aneurysm neck and the artery is tethered by the PcomA and not mobilized, the PcomA can be divided near the junction with the PCA. The procedure permits PCA mobilization and exposes the neck of the aneurysm. We applied this procedure to a patient with a ruptured aneurysm of the basilar tip. The postoperative course was uneventful except for transient left oculomotor nerve palsy. Postoperative cerebral angiography and magnetic resonance imaging confirmed the respective disappearance of the aneurysm and no new ischemic lesions. The subtemporal approach allows safer and easier division of the PcomA near the junction to the PCA compared with the pterional approach, and the present procedure is more suitable for the subtemporal approach
Effect of continuous cisternal cerebrospinal fluid drainage for patients with thin subarachnoid hemorrhage
External cerebrospinal fluid (CSF) drainage is an effective method to remove massive subarachnoid hemorrhage (SAH), but carries the risk of meningitis and shunt-dependent hydrocephalus. This study investigated whether postoperative cisternal CSF drainage affects the incidence of cerebral vasospasm and clinical outcome in patients with thin SAH. Seventy-eight patients with thin SAH, 22 men and 56 women aged from 17 to 73 years (mean 51.2 years), underwent surgical repair for ruptured anterior circulation aneurysm. Patients were divided into groups with (38 patients) and without (40 patients) postoperative cisternal CSF drainage, and the incidences of angiographical and symptomatic vasospasm, shunt-dependent hydrocephalus, meningitis, and the clinical outcome were compared. The incidences of angiographical vasospasm (31.6% vs 50.0%), symptomatic vasospasm (7.9% vs 12.5%), shunt-dependent hydrocephalus (5.3% vs 0%), and meningitis (2.6% vs 0%) did not differ between patients with and without cisternal CSF drainage. All patients in both groups resulted in good recovery. Postoperative cisternal CSF drainage does not affect the incidence of cerebral vasospasm or the clinical outcome in patients with thin SAH
Hemorrhagic infarction at 33 days after birth in a healthy full-term neonate
Intraparenchymal hemorrhage in the full-term neonate rarely occurs more than 2 weeks after birth, and its definitive cause remains unclear. In the present report, a case of a patient with intraparenchymal hemorrhage occurring 33 days after birth is described. Histological examination of the brain tissue obtained during hematoma evacuation through craniotomy showed hemorrhagic infarction. Patent foramen ovale may have been present and this may have led to spontaneous paradoxical cerebral embolism followed by hemorrhagic infarction
Prediction of stroke patients’ bedroom-stay duration: machine-learning approach using wearable sensor data
Background: The importance of being physically active and avoiding staying in bed has been recognized in stroke rehabilitation. However, studies have pointed out that stroke patients admitted to rehabilitation units often spend most of their day immobile and inactive, with limited opportunities for activity outside their bedrooms. To address this issue, it is necessary to record the duration of stroke patients staying in their bedrooms, but it is impractical for medical providers to do this manually during their daily work of providing care. Although an automated approach using wearable devices and access points is more practical, implementing these access points into medical facilities is costly. However, when combined with machine learning, predicting the duration of stroke patients staying in their bedrooms is possible with reduced cost. We assessed using machine learning to estimate bedroom-stay duration using activity data recorded with wearable devices.Method: We recruited 99 stroke hemiparesis inpatients and conducted 343 measurements. Data on electrocardiograms and chest acceleration were measured using a wearable device, and the location name of the access point that detected the signal of the device was recorded. We first investigated the correlation between bedroom-stay duration measured from the access point as the objective variable and activity data measured with a wearable device and demographic information as explanatory variables. To evaluate the duration predictability, we then compared machine-learning models commonly used in medical studies.Results: We conducted 228 measurements that surpassed a 90% data-acquisition rate using Bluetooth Low Energy. Among the explanatory variables, the period spent reclining and sitting/standing were correlated with bedroom-stay duration (Spearman’s rank correlation coefficient (R) of 0.56 and −0.52, p < 0.001). Interestingly, the sum of the motor and cognitive categories of the functional independence measure, clinical indicators of the abilities of stroke patients, lacked correlation. The correlation between the actual bedroom-stay duration and predicted one using machine-learning models resulted in an R of 0.72 and p < 0.001, suggesting the possibility of predicting bedroom-stay duration from activity data and demographics.Conclusion: Wearable devices, coupled with machine learning, can predict the duration of patients staying in their bedrooms. Once trained, the machine-learning model can predict without continuously tracking the actual location, enabling more cost-effective and privacy-centric future measurements
Optimizing the timing of 3.6 mg Pegfilgrastim Administration for Dose-Dense Chemotherapy in Japanese Patients with Breast Cancer
Perioperative dose-dense chemotherapy (DDCT) with pegfilgrastim (Peg) prophylaxis is a standard treatment for high-risk breast cancer. We explored the optimal timing of administration of 3.6 mg Peg, the dose approved in Japan. In the phase II feasibility study of DDCT (adriamycin+cyclophosphamide or epirubicin+cyclophosphamide followed by paclitaxel) for breast cancer, we investigated the feasibility, safety, neutrophil transition, and optimal timing of Peg treatment by administering Peg at days 2, 3, and 4 post-chemotherapy (P2, P3, and P4 groups, respectively). Among the 52 women enrolled, 13 were aged > 60 years. The anthracycline sequence was administered to P2 (n=33), P3 (n=5), and P4 (n=14) patients, and the taxane sequence to P2 (n=38) and P3 (n=6) patients. Both sequences showed no interaction between Peg administration timing and treatment discontinuation, treatment delay, or dose reduction. However, the relative dose intensity (RDI) was significantly different among the groups. The neutrophil count transition differed significantly among the groups receiving the anthracycline sequence. However, the neutrophil count remained in the appropriate range for both sequences in the P2 group. The timing of Peg administration did not substantially affect the feasibility or safety of DDCT. Postoperative day 2 might be the optimal timing for DDCT
Superb Microvascular Imaging Ultrasound for Cervical Carotid Artery Stenosis for Prediction of the Development of Microembolic Signals on Transcranial Doppler during Carotid Exposure in Endarterectomy
Introduction: During exposure of the carotid arteries, embolism from the surgical site is recognized as a primary cause of neurological deficits or new cerebral ischemic lesions following carotid endarterectomy (CEA), and associations have been reported between histological neovascularization in the carotid plaque and both plaque vulnerability and the development of artery-to-artery embolism. Superb microvascular imaging (SMI) enables accurate visualization of neovessels in the carotid plaque without the use of intravenous contrast. This study aimed to determine whether preoperative SMI ultrasound for cervical carotid artery stenosis predicts the development of microembolic signals (MES) on transcranial Doppler (TCD) during exposure of the carotid arteries in CEA. Methods: Preoperative cervical carotid artery SMI ultrasound followed by CEA under TCD monitoring of MES in the ipsilateral middle cerebral artery was conducted in 70 patients previously diagnosed with internal carotid artery stenosis (defined as ≥70%). First, observers visually identified intraplaque microvascular flow (IMVF) signals as moving enhancements located near the surface of the carotid plaque within the plaque on SMI ultrasonograms. Next, regions of interest (ROI) were manually placed at the identified IMVF signals (or at arbitrary places within the plaque when no IMVF signals were identified within the carotid plaque) and the carotid lumen, and time-intensity curves of the IMVF signal and lumen ROI were generated. Ten heartbeat cycles of both time-intensity curves were segmented into each heartbeat cycle based on gated electrocardiogram findings and averaged with respect to the IMVF signal and lumen ROI. The difference between the maximum and minimum intensities (ID) was calculated based on the averaged IMVF signal (IDIMVF) and lumen (IDl) curves. Finally, the ratio of IDIMVF to IDl was calculated. Results: MES during exposure of the carotid arteries were detected in 17 patients (24%). The incidence of identification of IMVF signals was significantly greater in patients with MES (94%) than in those without (57%; p = 0.0067). The IDIMVF/IDl ratio was significantly greater in patients with MES (0.108 ± 0.120) than in those without (0.017 ± 0.042; p < 0.0001). The specificity and positive predictive value for the IDIMVF/IDl ratio for prediction of the development of MES were significantly higher than those for the identification of IMVF signals. Logistic regression analysis revealed that only the IDIMVF/IDl ratio was significantly associated with the development of MES (95% CI 101.1–3,628.9; p = 0.0048). Conclusion: Preoperative cervical carotid artery SMI ultrasound predicts the development of MES on TCD during exposure of the carotid arteries in CEA
Current Performance and On-Going Improvements of the 8.2 m Subaru Telescope
An overview of the current status of the 8.2 m Subaru Telescope constructed
and operated at Mauna Kea, Hawaii, by the National Astronomical Observatory of
Japan is presented. The basic design concept and the verified performance of
the telescope system are described. Also given are the status of the instrument
package offered to the astronomical community, the status of operation, and
some of the future plans. The status of the telescope reported in a number of
SPIE papers as of the summer of 2002 are incorporated with some updates
included as of 2004 February. However, readers are encouraged to check the most
updated status of the telescope through the home page,
http://subarutelescope.org/index.html, and/or the direct contact with the
observatory staff.Comment: 18 pages (17 pages in published version), 29 figures (GIF format),
This is the version before the galley proo
Generation of transgenic cynomolgus monkeys that express green fluorescent protein throughout the whole body.
Nonhuman primates are valuable for human disease modelling, because rodents poorly recapitulate some human diseases such as Parkinson\u27s disease and Alzheimer\u27s disease amongst others. Here, we report for the first time, the generation of green fluorescent protein (GFP) transgenic cynomolgus monkeys by lentivirus infection. Our data show that the use of a human cytomegalovirus immediate-early enhancer and chicken beta actin promoter (CAG) directed the ubiquitous expression of the transgene in cynomolgus monkeys. We also found that injection into mature oocytes before fertilization achieved homogenous expression of GFP in each tissue, including the amnion, and fibroblasts, whereas injection into fertilized oocytes generated a transgenic cynomolgus monkey with mosaic GFP expression. Thus, the injection timing was important to create transgenic cynomolgus monkeys that expressed GFP homogenously in each of the various tissues. The strategy established in this work will be useful for the generation of transgenic cynomolgus monkeys for transplantation studies as well as biomedical research
A newly designed hydroxyapatite ceramic burr-hole button
Hiroshi Kashimura, Kuniaki Ogasawara, Yoshitaka Kubo, Kenji Yoshida, Atsushi Sugawara, Akira OgawaDepartment of Neurosurgery, Iwate Medical University School of Medicine, Morioka, Iwate, JapanAbstract: Conventional burr-hole buttons sometimes do not fit the burr hole well due to the curvature of the surrounding bone. An irregular surface at the border between the button and the surrounding skull may appear unaesthetic. The major problem is the difference between the curvature radius of the skull and the burr-hole button in contact with the skull. To solve this problem, the authors designed a button made of hydroxyapatite ceramic to snugly fit the burr hole. The specifications of this device and its clinical application are described here.Keywords: hydroxyapatite ceramic, bone curvature, burr-hole button, craniotomy, cosmetic outcom