著者
Tatsuya Ishikawa Akira Kurashima
出版者
The Plankton Society of Japan, The Japanese Association of Benthology
雑誌
Plankton and Benthos Research (ISSN:18808247)
巻号頁・発行日
vol.15, no.2, pp.112-120, 2020-05-27 (Released:2020-05-30)
参考文献数
50
被引用文献数
3

This study aimed to estimate the feeding pressure of a Diadema setosum population on a barren ground in Kata Bay, Mie Prefecture, Japan, which is a temperate region. We combined data of the feeding rate of D. setosum from tank experiments and of the D. setosum population dynamics obtained from monthly surveys. We conducted tank experiments to clarify the relationships between the feeding rate of D. setosum and the water temperature and test diameter of the sea urchins. The feeding rate and water temperature were positively correlated over the range of 15°C to 30°C. The test diameter composition of the D. setosum population in Kata Bay was stable throughout the study period (June 2014 to May 2015). The results revealed distinct seasonal changes in the feeding pressure of the D. setosum population owing to temperature variations.
著者
Tatsuya Ishikawa Miyuki Maegawa Akira Kurashima
出版者
日本プランクトン学会、日本ベントス学会
雑誌
Plankton and Benthos Research (ISSN:18808247)
巻号頁・発行日
vol.11, no.4, pp.112-119, 2016-11-25 (Released:2016-11-23)
参考文献数
30
被引用文献数
13

This study examines the effects of the sea urchin Diadema setosum on algal composition, coverage and biomass on barren ground. In cage experiments, the effects of D. setosum density were examined at 5 levels over the range of 0–8 ind. m−2. Algal coverage and number of species, densities and lengths of Sargassum spp. on experimental blocks in each cage were measured monthly. In the cage without D. setosum, algal coverage and biomass were higher than in cages with D. setosum. For D. setosum density of 1 ind. m−2 and higher, decreased algal coverage and decreased biomass and density of Sargassum spp. were observed. D. setosum at a density higher than 2 ind. m−2 had a negative effect on algal species numbers. Consequently, algae could grow when the D. setosum density was fewer than 2 ind. m−2. This study revealed that grazing by D. setosum has a great effect on the seaweed bed ecosystems along the coast of central Japan.
著者
Tatsuya ISHIKAWA Naoki NAKAYAMA Junta MOROI Norikata KOBAYASHI Hideya KAWAI Tastushi MUTO Nobuyuki YASUI
出版者
The Japan Neurosurgical Society
雑誌
Neurologia medico-chirurgica (ISSN:04708105)
巻号頁・発行日
vol.49, no.6, pp.273-278, 2009 (Released:2009-06-25)
参考文献数
18
被引用文献数
22 30

The concept of optimum closure line was applied to a series of 51 consecutive middle cerebral artery aneurysms (14 ruptured, 37 unruptured) in 41 patients, 16 men and 25 women aged 29-79 years (mean 59.1 years). Visual inspection through the operating microscope revealed 3 types of aneurysm based on the origin of the aneurysm: bifurcation type (n = 39), trunk type (n = 9), and combined type (n = 3). Clipping along the optimum closure line should restore the vascular structure to the original configuration. Combination clip techniques were useful to form a curved closure line. This technique requires adequate operative fields with dissection of the aneurysm and related arteries from the neighboring structures as far as possible. The closure line concept is helpful to decide how to apply clips for particular aneurysms to avoid risks of ischemic complication and future recurrence. Combination clip techniques are often necessary to match a curved closure line.
著者
Takahiro YOKOYAMA Tatsuya ISHIKAWA Yosuke MOTEKI Takayuki FUNATSU Koji YAMAGUCHI Seiichiro EGUCHI Hayato YAMAHATA Buntou RO Takakazu KAWAMATA
出版者
The Japan Neurosurgical Society
雑誌
NMC Case Report Journal (ISSN:21884226)
巻号頁・発行日
vol.10, pp.115-119, 2023-12-31 (Released:2023-04-21)
参考文献数
18

PulseRider (Cerenovus, Irvine, CA, USA) is a relatively novel device used for the treatment of wide-neck aneurysms with a coil-assisted effect. However, treatment options for recurrent aneurysms after PulseRider-assisted coil embolization remain controversial. Here we report a case of recurrent basilar tip aneurysm (BTA) treated with Enterprise 2 after PulseRider-assisted coil embolization. A woman in her 70s underwent coil embolization for a subarachnoid hemorrhage with ruptured BTA 16 years ago. Recurrence was detected at 6-year follow-up, and an additional coil embolization was performed. Nevertheless, gradual recurrence still occurred, and PulseRider-assisted coil embolization was performed without any complications 9 years after the second treatment. However, recurrence was detected once more at 6-month follow-up. Thus, stent-assisted coil embolization using Enterprise 2 (Cerenovus) through PulseRider was selected for angular remodeling. Enterprise 2 was deployed between the right P2 segment of the posterior cerebral artery (PCA) and basilar artery (BA) after an effective coil embolization, which achieved effective angular remodeling between the right PCA and BA. The patient's postoperative course was uneventful, and no recanalization was detected after half a year. Although PulseRider is effective for wide-neck aneurysm treatment, recurrence remains a possibility. Additional treatment using Enterprise 2 is safe and effective with the expectation of angular remodeling.
著者
Koji YAMAGUCHI Takayuki FUNATSU Yosuke MOTEKI Taku NONAKA Akihiro NIWA Kosuke IMANAKA Kilsoo KIM Tatsuya ISHIKAWA Tatsuki MOCHIZUKI Yoshikazu OKADA Takakazu KAWAMATA
出版者
The Japan Neurosurgical Society
雑誌
Neurologia medico-chirurgica (ISSN:04708105)
巻号頁・発行日
pp.2022-0307, (Released:2023-03-31)
参考文献数
18
被引用文献数
1

Various surgical treatments are available for occlusive subclavian and common carotid artery diseases. Nevertheless, to date, when cerebral endovascular treatment is utilized, revascularization via direct surgery may be required. This study reported five symptomatic cases of revascularization for CCA and SCA occlusive and stenotic lesions that were expected to be challenging to treat with endovascular treatment. We performed subclavian artery-common carotid artery or internal carotid artery bypass using artificial blood vessels or saphenous vein grafts in five patients with subclavian steal syndrome, symptomatic common carotid artery occlusion, and severe proximal common carotid artery stenosis. In this study, good bypass patency was achieved in all five cases. Although there were no intraoperative complications, one patient had a postoperative lymphatic leak. Moreover, there was no recurrence of stroke during postoperative follow-up for an average of 2 years. Conclusively, subclavian artery-common carotid artery bypass can be an effective surgical treatment for common carotid artery occlusion, proximal common carotid artery stenosis, and subclavian artery occlusion.
著者
Yuki TAKANO Tatsuya ISHIKAWA Takayuki FUNATSU Seiichiro EGUCHI Masatake SUMI Koji YAMAGUCHI Takakazu KAWAMATA
出版者
The Japan Neurosurgical Society
雑誌
NMC Case Report Journal (ISSN:21884226)
巻号頁・発行日
vol.9, pp.371-376, 2022-12-31 (Released:2022-11-09)
参考文献数
20

Spontaneous internal carotid artery dissection (CAD) is a relatively rare disease, with patients, including those with bilateral CAD, often recovering after conservative therapy. However, patients with symptomatic and progressive disease require urgent carotid artery stenting (CAS). If CAD extends to the petrous portion of the internal carotid artery (ICA), it is difficult to treat with a carotid stent alone. This report describes a rare case of consecutive spontaneous bilateral CAD that required an intracranial stent with an interval of 4 years between the first and second CAS. A 58-year-old man with a history of dyslipidemia was admitted for transient ischemic attacks. He underwent CAS with carotid and intracranial stents on the third day for the left CAD due to exacerbation of symptoms under antithrombotic therapy and new stroke on magnetic resonance imaging (MRI). He recovered well. However, 4 years after the initial treatment, the patient was admitted again because of a sudden headache, photophobia, and transient weakness of the left lower limb. He was diagnosed with CAD on the contralateral side. He underwent CAS with carotid and intracranial stents due to progressive neurological deterioration under antithrombotic therapy. After treatment, he was clinically stable without any new infarctions on a follow-up MRI. He was discharged without neurological deficit. Our case of bilateral internal CAD treatment demonstrated that early revascularization with immediate stenting with carotid and intracranial stents in CAD contributes to the prevention of extensive neurological damage, thereby providing a favorable outcome in some cases.
著者
Atsushi KUWANO Koji YAMAGUCHI Takayuki FUNATSU Yosuke MOTEKI Seiichiro EGUCHI Isamu MIURA Momo UCHIDA Kaname ITO Tatsuya ISHIKAWA Takakazu KAWAMATA
出版者
The Japan Neurosurgical Society
雑誌
NMC Case Report Journal (ISSN:21884226)
巻号頁・発行日
vol.9, pp.337-342, 2022-12-31 (Released:2022-10-13)
参考文献数
19
被引用文献数
1

Cavernous malformations of the midbrain have a higher rate of hemorrhage and a poorer prognosis than vascular malformations of other brain areas. Surgical resection of these lesions is often necessary to avoid neurological deficits in affected patients. Herein, the literature surrounding cavernous malformations was examined, and the case of a 48-year-old man with left hemiparesis and diplopia caused by incomplete right oculomotor nerve palsy, who was diagnosed with a hemorrhage from a midbrain cavernous malformation, was discussed. The lesion expanded gradually on magnetic resonance imaging and was symptomatic; radical removal of the lesion before the onset of irreversible symptoms due to recurring bleeding was therefore considered to be beneficial for the patient. Surgical removal of the entire cavernous malformations of the midbrain was performed using an interhemispheric transcallosal subchoroidal approach, with excellent postoperative results and complete recovery from the oculomotor nerve palsy and left hemiparesis. This case shows that this approach is the most appropriate for surgical resections of lesions in the upper midbrain.
著者
Tamon ANDO Tatsuya ISHIKAWA Takayuki FUNATSU Koji YAMAGUCHI Yosuke MOTEKI Seiichiro EGUCHI Momo UCHIDA Makiko SAKAGUCHI Masahiko NISHITANI Takakazu KAWAMATA
出版者
The Japan Neurosurgical Society
雑誌
NMC Case Report Journal (ISSN:21884226)
巻号頁・発行日
vol.9, pp.269-273, 2022-12-31 (Released:2022-08-26)
参考文献数
20

Kissing aneurysms refer to the condition in which two cerebral aneurysms with separate necks are in contact with each other. At present, there is scarce information on kissing aneurysms occurring near the vertebral artery (VA) -posterior inferior cerebellar artery (PICA). We report the first case of VA-PICA and nonbranched PICA kissing aneurysms, which were successfully treated with contralateral stenting after the anchor coil technique using two microcatheters. A 64-year-old woman was diagnosed with a left VA-PICA aneurysm (5.5 mm) and an adjacent small PICA aneurysm (2.5 mm) with the aneurysmal walls in close contact. For stenting, microcatheters were navigated to the PICA from the contralateral side, and framing coils for the anchor were placed into each aneurysm from the ipsilateral side. Next, a Neuroform Atlas stent was deployed from the PICA to the distal side of the VA, and coiling was completed using the jailing technique. The patient had a good postoperative course, and a left vertebral angiogram revealed complete occlusion of both aneurysms after 6 months. Adequate surgical planning and application of an appropriate stent-assisted coil embolization technique contributed to the success of the procedure in this rare case.