Publications by authors named "Kazuhiro Ando"

15 Publications

  • Page 1 of 1

Hemodynamic features of an intracranial aneurysm rupture predicted by perianeurysmal edema: A case report.

Surg Neurol Int 2021 10;12:49. Epub 2021 Feb 10.

Department of Neurosurgery, Niigata University, Brain Research Institute, Niigata, Japan.

Background: Perianeurysmal edema (PAE) has been suggested as an indicator of potential aneurysm rupture; however, the hemodynamic features of these aneurysms are still unknown. A computational fluid dynamic (CFD) analysis was performed to evaluate the hemodynamic features of a very rare case of a ruptured middle cerebral artery (MCA) aneurysm with PAE.

Case Description: A 65-year-old woman presented with disturbed consciousness. A subarachnoid hemorrhage due to an azygos anterior cerebral artery (ACA) aneurysm rupture was suspected. An unruptured MCA aneurysm with PAE was identified in the left temporal lobe. Although the ACA aneurysm was clipped to prevent re-bleeding, the MCA aneurysm subsequently ruptured 6 days later. Clipping of the MCA aneurysm was performed, and hemosiderin deposits suggestive of sentinel bleeding were found on the surface of the aneurysm dome. CFD analysis revealed unstable hemodynamic stress at the expanded bleb area after rupture, localized to the rupture site. Moreover, this analysis revealed flow impingement with pressure elevation and low wall shear stress, which indicated increased inflammation and aneurysm wall thinning that likely led to rupture.

Conclusion: Hemosiderin deposits at the aneurysm wall and PAE indicates leakage from a cerebral aneurysm. Hemodynamic stress at the aneurysm may promote an inflammatory response and lead to wall weakening accompanied by PAE. Based on our findings, we recommend that surgical intervention should be considered as the first line of treatment for such aneurysms to prevent rupture.
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http://dx.doi.org/10.25259/SNI_780_2020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7911146PMC
February 2021

Delayed Bleeding of Unruptured Intracranial Aneurysms After Coil Embolization: A Retrospective Case Series.

World Neurosurg 2021 Feb 20. Epub 2021 Feb 20.

Department of Neurosurgery, Brain Research Institute, Niigata University, Niigata, Japan.

Objective: Delayed bleeding of unruptured intracranial aneurysms (UIAs) after coil embolization is rare; this study aimed to analyze the occurrence of delayed bleeding of UIAs after coil embolization.

Methods: We retrospectively analyzed patients with UIAs after coil embolization between January 2002 and December 2018 and assessed the features of UIAs with delayed bleeding after coil embolization.

Results: Analysis included 307 patients with 335 UIAs. Mean follow-up was 7.1 ± 4.9 years, and total follow-up was 2365 aneurysm-years. There were 271 (80.9%) aneurysms located in the anterior circulation and 64 (19.1%) aneurysms located in the posterior circulation. Significant differences were observed between the 2 groups in terms of maximum size of the aneurysm (P < 0.01), width of the aneurysm neck (P < 0.01), and number of retreatment cases (P < 0.01). During the follow-up period, delayed bleeding occurred in 4 aneurysms (annual bleeding rate of 0.17%); all were located in the posterior circulation. The original size was not relatively large (mean 8.6 ± 2.4 mm). All aneurysms bled within 5 years (mean 35 ± 9.6 months) after the initial treatment. Two were de novo aneurysms that developed adjacent to the coiled aneurysms and were not detected on follow-up magnetic resonance angiography.

Conclusions: Cautious follow-up of UIAs with digital subtraction angiography is important, articularly within the first 5 years after the procedure. If there are changes in the anatomic outcomes, short-term reassessment or additional treatment should be actively considered, particularly for aneurysms in the posterior circulation.
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http://dx.doi.org/10.1016/j.wneu.2021.02.061DOI Listing
February 2021

Possibility of Worsening Flow Diversion Effect Due to Morphological Changes of a Stented Artery With Multiple Overlapping Stents for Partially Thrombosed Vertebral Artery Aneurysms.

Front Neurol 2020 15;11:611124. Epub 2020 Dec 15.

Department of Neurosurgery, Brain Research Institute, Niigata University, Niigata, Japan.

Morphological changes of a stented artery can cause a flow diversion effect to reduce intra-aneurysmal flow; however, there is a potential for the negative effect of increased intra-aneurysmal flow. We present cases with multiple overlapping stents for a partially thrombosed vertebral artery aneurysm and characterize the hemodynamic properties of a recurrent case by focusing on the morphological changes of the stented artery. Between October 2017 and April 2019, four consecutive cases of symptomatic unruptured large and giant partially thrombosed vertebral artery aneurysms were treated with multiple overlapping low-profile visualized intraluminal support stents and no coils. Both angiographic and clinical outcomes were assessed. Computational fluid dynamics analysis was performed to clarify hemodynamic features. The degree of pressure elevation was calculated as the pressure difference (Pd). Wall shear stress (WSS) was also calculated. In three of the four cases, successful flow reduction was achieved with no morphological change of the stented arteries. The patients' symptoms were gradually improved. The remaining case required additional stents after the initial treatment. In the recurrent case, Pd was noticeably elevated at the aneurysm neck after treatment, and WSS was generally increased in the area due to altered blood flow into the aneurysm dome caused by morphological changes of the stented artery. Overlapping stents can be used for the treatment of large and giant thrombosed vertebral artery aneurysms with flow diversion effect; however, morphological changes of the stented artery requires careful attention as it may lead to an increase in the intra-aneurysmal flow, causing negative outcomes.
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http://dx.doi.org/10.3389/fneur.2020.611124DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7770215PMC
December 2020

Unilateral oculomotor nerve palsy caused by arterial compression accompanying subarachnoid hemorrhage: a case report.

Acta Neurochir (Wien) 2021 03 5;163(3):813-816. Epub 2020 Nov 5.

Department of Neurosurgery, Brain Research Institute, Niigata University, 1-757 Asahimachidori, Chuo-ku, Niigata, Niigata, 951-8585, Japan.

Unilateral oculomotor nerve palsy, often caused by aneurysmal compression, is one of the decisive findings for confirming the site of a ruptured aneurysm. However, arterial compression can also cause unilateral oculomotor nerve palsy. Here, we present the case of a 59-year-old woman with a ruptured right internal carotid-posterior communicating artery aneurysm accompanied by contralateral oculomotor nerve palsy. The nerve was found to be compressed by the posterior cerebral artery and was isolated from the ruptured aneurysm. When confirming a ruptured aneurysm based on the evidence of unilateral oculomotor palsy, the arteries surrounding the nerve must be thoroughly assessed.
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http://dx.doi.org/10.1007/s00701-020-04633-xDOI Listing
March 2021

[Endovascular Revascularization for Acute Ischemic Stroke Related to Blunt Carotid Injury:A Case Report].

No Shinkei Geka 2020 Jun;48(6):527-532

Department of Neurosurgery, Brain Research Institute, Niigata University.

Although blunt carotid artery injury is known as an important cause of ischemic stroke, the role of the endovascular treatment for acute ischemic stroke related to blunt carotid injuries remains unclear. We report the case of a patient with acute ischemic stroke secondary to blunt carotid artery injury who was treated with endovascular revascularization. A 46-year-old man suffered from sudden left-sided hemiparesis a day after a strike from a Japanese fencing staff on his right neck. 3D-CT angiography revealed tandem internal carotid artery occlusions of the cervical and C1 portions. We performed endovascular revascularization with carotid artery stenting and direct aspiration of the thrombus and achieved complete recanalization. The patient recovered almost completely. We conclude that endovascular revascularization should not be withheld from patients with acute ischemic stroke related to blunt carotid injury.
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http://dx.doi.org/10.11477/mf.1436204223DOI Listing
June 2020

Safety and feasibility of the distal transradial approach: A novel technique for diagnostic cerebral angiography.

Interv Neuroradiol 2020 Dec 13;26(6):713-718. Epub 2020 May 13.

Department of Neurosurgery, Brain Research Institute, Niigata University, Niigata, Japan.

Purpose: We aimed to evaluate the safety and feasibility of the distal transradial approach (DTRA) as a novel technique for cerebral angiography based on our institutional initial experience.

Methods: We retrospectively analyzed our institutional database of consecutive diagnostic cerebral angiographies performed with DTRA from December 2018 to August 2019. Patient demographics and clinical and procedural data were recorded.

Results: In total, 51 diagnostic cerebral angiographies in 51 patients (age, 15-83 years; mean age, 59.4 years, SD 13.5; 35 (69%) females) were performed or attempted with DTRA. Ultrasound evaluation showed that the mean inner distal radial artery diameter was significantly smaller than the mean inner forearm radial artery diameter (2.19 mm vs. 2.56 mm, P < 0.001). Cannulation via the distal radial artery was successful in 47 (92%) procedures. In the four procedures that failed, operators converted to the ipsilateral transradial approach without repositioning or redraping. Selective catheterization of the intended vessel was achieved in 64 (91%) of 70 vessels. In the remaining six, operators achieved the objective of the examination with angiography injecting from proximal and conversion to another approach was not required. One patient experienced temporary numbness around the puncture site after the procedure. No radial artery occlusion was identified in the patients who underwent ultrasound evaluation.

Conclusion: Our results demonstrate that DTRA could become a standard approach for diagnostic cerebral angiography owing to the low complication rate and the high cannulation success rate.
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http://dx.doi.org/10.1177/1591019920925709DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7724605PMC
December 2020

Treatment Strategies for Infectious Intracranial Aneurysms: Report of Three Cases and Review of the Literature.

Neurol Med Chir (Tokyo) 2019 Sep 4;59(9):344-350. Epub 2019 Jul 4.

Department of Neurosurgery, Brain Research Institute, Niigata University.

We retrospectively reviewed the cases of three patients with infectious intracranial aneurysms (IIAs), and discuss the indications for surgical and endovascular treatments. We treated two men and one woman with a total of six aneurysms. The mean age was 43.3 years, ranging from 36 to 51 years. One patient presented initially with an intraparenchymal hemorrhage, one with mass effect, and the other one had four aneurysms (one causing subarachnoid hemorrhages and the other causing delayed intraparenchymal hemorrhages). The average size of all aneurysms was 12.2 mm (range, 2-50 mm). They were preferentially located in the distal posterior cerebral artery, and then, in the middle cerebral artery. All cases were caused by infective endocarditis. We selected endovascular treatments for five aneurysms and treated all but one within 24 h from detection. One aneurysm was treated by combined therapy with endovascular intervention and surgery. After treatment, none of the IIAs presented angiographical recurrence or re-bleeding. If feasible, endovascular treatment is probably the first choice, but a combined surgical and endovascular approach should be considered if surgery or endovascular treatment alone are not feasible. The method of treatment should be individualized. For cases with high risk of aneurysm rupture, treatment should be performed as soon as possible.
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http://dx.doi.org/10.2176/nmc.oa.2019-0051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6753255PMC
September 2019

Successful Resection of a Growing Distal Medial Lenticulostriate Artery Pseudoaneurysm Presenting with Isolated Intraventricular Hemorrhage.

J Stroke Cerebrovasc Dis 2017 Oct 18;26(10):e206-e209. Epub 2017 Aug 18.

Department of Neurosurgery, Cerebrovascular Center, Niigata Rosai Hospital, Japan Organization of Occupational Health and Safety, Niigata, Japan.

Introduction: Distal medial lenticulostriate artery (LSA) aneurysms associated with isolated intraventricular hemorrhage (IVH) are extremely rare. We report a very rare case of the isolated IVH due to the rupture of the distal medial LSA pseudoaneurysm that was not visible at the initial angiography but later emerged and grew.

Case Report: A 61-year-old woman with a history of hypertension had sudden onset of severe headache and mild consciousness disturbance. The computed tomography scan revealed the IVH, but the initial angiographies showed no evidence of aneurysm. The follow-up magnetic resonance imaging revealed that an intraventricular mass, arising from the right distal medial LSA, emerged and grew into the right anterior horn. Considering the risk of rebleeding, we resected the mass lesion via the transsulcal transventricular approach. The postoperative imaging showed complete obliteration of the mass lesion. Histopathological analysis indicated the pseudoaneurysm. The patient was discharged without any neurological deficit.

Conclusions: The careful and repetitive follow-up imaging should be done in the cases with isolated IVH even if the initial image evaluations are unrevealing. The transsulcal transventricular approach can be the most minimally invasive surgical option for intraventricular lesion.
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http://dx.doi.org/10.1016/j.jstrokecerebrovasdis.2017.07.021DOI Listing
October 2017

[A Case of Fibromuscular Dysplasia in a Patient with Various Main Trunk Dissections in the Head and Neck over a Short Period].

No Shinkei Geka 2016 Jul;44(7):583-90

Department of Neurosurgery, Niigata City General Hospital.

We report a case of subarachnoid hemorrhage(SAH)from an intracranial vertebral artery(VA)dissection in a patient with fibromuscular dysplasia(FMD)who presented with headache. A 54-year-old woman complained of spontaneous occipital headache. The dilatation of the left VA was detected on magnetic resonance angiography(MRA). She was diagnosed with left VA dissection(headache onset type). After sudden onset of headache on the second day of hospitalization, her consciousness level, as defined by the Japan Coma Scale, was 300. Computed tomography(CT)revealed SAH. Cerebral angiography showed the dilatation of the left intracranial VA and contrast material pooling, which was suspected to be a sign of dissection. We performed VA intravascular ligation by coil embolization. The postoperative course was good but postoperative MRA revealed arterial wall irregularities in both the extra cranial internal carotid artery and the right VA. Cerebral angiography showed the presence of the string-of-beads sign at these arteries. She was diagnosed with FMD. SAH might develop during the follow-up period in patients with VA dissection, even those in whom the initial symptom is headache. In addition, cases of FMD might also be complicated by various lesions of the main trunk of the cerebral artery.
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http://dx.doi.org/10.11477/mf.1436203334DOI Listing
July 2016

[Clinical Study on Cerebellar Contusion:A Report on 9 Cases and Literature Review].

No Shinkei Geka 2015 Oct;43(10):901-6

Department of Neurosurgery, Niigata City General Hospital.

We report 9 cases of cerebellar contusion from April 2011 to September 2014 at our department. Frequency, clinicoradiological findings, mechanism of injury, treatments, and outcomes were retrospectively analyzed. Of 239 head injury cases admitted to our department during the same period, 9(3.8%)were diagnosed as cerebellar contusion. Among these 9 cases, 7 were men, and 2 were women. The patient age ranged from 12 to 83 years with a mean age of 64.7 years. The mechanism of injury was traffic accident in one patient, and fall in 8. All cases were associated with direct head trauma to the occiput, and radiographic studies showed occipital bone fracture in 8 cases. Six cases were managed conservatively. Three cases underwent suboccipital craniectomies and clot evacuations. Glasgow Outcome Scale(GOS)score at discharge were Good Recovery(GR)in 2, Moderate Disability(MD)in 2, Severe Disability(SD)in 3, Vegetative State(VS)in 1, and Dead(D)in 1. GOS scores in surgically treated cases were GR in 1, SD in 1, and VS in 1. Supratentorial severe traumatic lesions were concomitant with poor prognosis. Coup injury was a significant cause of cerebellar contusion. External decompression and clot evacuation were useful in patients who suffered severe cerebellar contusion;however, concomitant supratentorial lesions influenced the prognosis.
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http://dx.doi.org/10.11477/mf.1436203144DOI Listing
October 2015

[Pure motor monoparesis of a lower limb due to head injury: a case report].

Brain Nerve 2012 Dec;64(12):1427-30

Department of Neurosurgery, Akita Red Cross Hospital, Japan.

A 70-year-old woman sustained a head injury after a motor vehicle accident. Physical examination conducted on admission revealed pure motor monoparesis (PMM) and pathological reflexes in the right lower extremity. Her left lower extremity and upper extremities were intact. Computed tomography showed a spotty high-density lesion in the left precentral gyrus and a subgaleal hematoma in the left occipital region. Magnetic resonance imaging was performed on the next day. Fluid-attenuated inversion recovery (FLAIR) imaging demonstrated a high-intensity lesion in the left precentral gyrus, and T₂ imaging revealed a low-intensity lesion suggesting a small hemorrhage in the same area. The small hemorrhage and perifocal edema were identified on diffusion-weighted images in which low- and high-intensity lesions were observed in the anterior and posterior left precentral gyrus, respectively. Subsequent neurological examinations over 2 weeks showed improvement. We discuss the clinical presentation, diagnosis, and treatment of PMM due to head injury. We concluded that FLAIR and T₂ and diffusion-weighted imaging may be useful techniques for diagnosing PMM due to head injury.
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December 2012

Eye movement during facial affect recognition by patients with schizophrenia, using Japanese pictures of facial affect.

Percept Mot Skills 2011 Oct;113(2):409-20

Department of Community Psychiatric Nursing, School of Nursing, Faculty of Medicine, University of Miyazaki, Japan.

A possible relationship between recognition of facial affect and aberrant eye movement was examined in patients with schizophrenia. A Japanese version of standard pictures of facial affect was prepared. These pictures of basic emotions (surprise, anger, happiness, disgust, fear, sadness) were shown to 19 schizophrenic patients and 20 healthy controls who identified emotions while their eye movements were measured. The proportion of correct identifications of 'disgust' was significantly lower for schizophrenic patients, their eye fixation time was significantly longer for all pictures of facial affect, and their eye movement speed was slower for some facial affects (surprise, fear, and sadness). One index, eye fixation time for "happiness," showed a significant difference between the high- and low-dosage antipsychotic drug groups. Some expected facial affect recognition disorder was seen in schizophrenic patients responding to the Japanese version of affect pictures, but there was no correlation between facial affect recognition disorder and aberrant eye movement.
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http://dx.doi.org/10.2466/02.13.15.27.PMS.113.5.409-420DOI Listing
October 2011

The possibility of determination of accuracy of performance just before the onset of a reaching task using movement-related cortical potentials.

Med Biol Eng Comput 2010 Sep 21;48(9):845-52. Epub 2010 Jul 21.

Department of Management Systems Engineering, Tokyo Metropolitan University, Tokyo, Japan.

This study aimed to examine the relationships among electroencephalogram parameters as physiological indices, ballistic movement as an index of operation, and accuracy of task performance. Experiments were conducted using a "reaching" task, in which subjects touched the target appearing 300 pixels away from a start point in a vertical direction on a touch-sensitive screen with the forefinger. During experiments, EEG, EMG as trigger, high-speed camera images, and task efficiency were acquired. Significant differences between the high- and low-performance groups were clearly confirmed on the slope of NS (negative slope) in movement-related cortical potentials (MRCPs) acquired from Fz (p < 0.05) and Cz (p < 0.05). Furthermore, a difference between these groups was confirmed in duration of ballistic movement. Based on our findings, we discuss whether it is possible to extract MRCP rapidly and automatically without using signal averaging and also to estimate accuracy just before a motion is executed.
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http://dx.doi.org/10.1007/s11517-010-0664-4DOI Listing
September 2010

An exploratory study of long-term neurocognitive outcomes following recovery from opportunistic brain infections in HIV+ adults.

J Clin Exp Neuropsychol 2008 Oct 8;30(7):836-43. Epub 2008 Feb 8.

Los Angeles-National Neurological AIDS Bank, University of California, Los Angeles, CA 90025, USA.

Central nervous system opportunistic infections (CNS-OI) are a significant cause of morbidity and mortality in AIDS. While current interventions are increasingly successful in treating CNS-OI, little information exists regarding long-term behavioral outcomes among survivors. In this exploratory study we examined neurocognitive data among three groups of adults with different AIDS-related CNS-OI: 15 with past cryptococcal meningitis (CM), 8 with toxoplasmosis encephalitis (TE), and 8 with progressive multifocal leukoencephalopathy (PML). A group of 61 individuals with AIDS, but without CNS-OI, was used as a comparison group. A battery of standardized neuropsychological tests assessing a variety of cognitive domains was administered upon entry. Results indicate that individuals with a history of CNS-OI were most impaired on measures of cognitive and psychomotor speed relative to the HIV+ comparison group. Among the CNS-OI groups, individuals with history of TE had the most severe and varied deficits. The results are discussed in relation to what is known about the neuropathological consequences of the various CNS-OIs. While this is the first systematic group study of residual CNS-OI effects on neurocognitive function, future studies employing more participants, perhaps focusing on specific CNS-OIs, will further characterize the long-term outcomes in AIDS-related CNS-OI.
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http://dx.doi.org/10.1080/13803390701819036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2886735PMC
October 2008

High-performance fluorescent particles prepared via miniemulsion polymerization.

J Colloid Interface Sci 2005 May;285(2):619-26

Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Yokohama 223-8522, Japan.

Highly fluorescent polymer particles were prepared with Eu beta-diketonates complex as a fluorophore by miniemulsion polymerization technique. Eu beta-diketonates complex has a long decay time, a large Stokes shift, and very narrow emission bands in comparison with other organic fluorescent compounds. Aqueous miniemulsion was prepared by mixing monomer, crosslinker, hydrophobe, and Eu beta-diketonates complex and then putting the mixture into an aqueous solution of surfactant, followed by ultrasonication. An aqueous solution of initiator was added to the miniemulsion to obtain fluorescent polymer particles, which were monodispersed without aggregation. Particle size was decreased to deca-nano scale by increasing the amount of surfactant. Fluorescent intensity was increased by using Eu beta-complex coordinated with additional ligand. Further fluorescence quantum yields and fluorescent properties in the presence of DNA were investigated to the confirm superiority of Eu beta-diketonates complexes in polymer particles.
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http://dx.doi.org/10.1016/j.jcis.2004.12.020DOI Listing
May 2005