Kazumasa Orihashi

Kochi University, Kôti, Kōchi, Japan

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Publications (250)393.31 Total impact

  • No preview · Article · Oct 2015 · Journal of the American College of Surgeons
  • Hideaki Nishimori · Masaki Yamamoto · Kazumasa Orihashi

    No preview · Article · Sep 2015 · The Journal of thoracic and cardiovascular surgery
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    Preview · Article · Aug 2015
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    ABSTRACT: We encountered a rare case of infection in a vascular graft created using the elephant trunk technique. A 65-year-old woman who underwent total arch replacement with the elephant trunk technique was re-admitted with fever. She developed embolization of multiple organs from vegetation attached to the elephant trunk graft which was elucidated by transesophageal echocardiography. Surgery for ruptured jejunal artery aneurysm was performed, and the graft infection healed after long-term antibiotic therapy with the prosthesis left in situ. Graft infection may generate vegetations on an elephant trunk graft. Transesophageal echocardiography is a helpful tool for accurate diagnosis.
    No preview · Article · Jun 2015 · General Thoracic and Cardiovascular Surgery
  • Kazumasa Orihashi
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    ABSTRACT: Mesenteric ischemia complicated by acute aortic dissection (AAD) is uncommon, but serious, as there is no established treatment strategy and it can progress rapidly to multi-organ failure. Diagnosing mesenteric ischemia before necrotic change is difficult, not only for primary care physicians, but even for gastrointestinal or cardiovascular surgeons as it can occur at any time during surgery. Thus, measures need to be in place at the bedside to enable us to obtain information on visceral perfusion. It is often difficult to decide which of laparotomy or aortic repair should be performed first, especially when there is associated shock or malperfusion of other vital organs. The standard surgical procedures for mesenteric ischemia are prompt revascularization of the mesenteric artery and, if needed, resection of necrotic intestine. However, the development of endovascular treatment and the introduction of hybrid ORs have improved the treatment strategies for mesenteric ischemia. This article reviews the issues of "diagnosis" in relation to the mechanism of mesenteric ischemia, and discusses the current "treatment strategies".
    No preview · Article · May 2015 · Surgery Today
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    ABSTRACT: In most general thoracic operations performed via standard posterolateral thoracotomy, such as for descending aortic aneurysms and lung cancer, the latissimus dorsi (LD) muscle is divided. However, division of the LD can hamper reconstructive surgery because the initial operation creates unstable blood flow to the divided LD. We conducted this study to assess blood flow in a divided distal LD muscle flap using intraoperative indocyanine green-fluorescence angiography (ICG-FA) with the Hyper Eye Medical System(®) (Mizuho Medical Co., Ltd., Tokyo, Japan). The subjects were 11 patients who underwent posterolateral thoracotomy with reconstructive surgery using a divided distal LD and other peripheral muscle flaps. Intraoperative ICG-FA was conducted to assess blood flow to the LD. Intraoperative ICG-FA revealed that at least two intercostal perforators from the sixth to the tenth intercostal spaces were preserved as feeding vessels to the divided distal LD. There were no major complications associated with inadequate blood flow to the muscle flaps. Intraoperative ICG-FA proved extremely useful for assessing altered blood flow of the divided LD and for selecting preserved intercostal perforators.
    No preview · Article · May 2015 · Surgery Today
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    ABSTRACT: The present study was designed to evaluate the efficacy of photothermal ablation therapy for lung cancer by low-power near-infrared laser and topical injection of indocyanine green (ICG). In vitro study 1: an 808 nm laser with 250 mW was irradiated for 10 minutes using different dilutions of ICG and the temporal thermal effect was monitored. ICG (1 mL of 0.5 g/L) was heated to a temperature of >30°C from the base temperature by laser irradiation. In vitro study 2: the cytotoxic effect of hyperthermia on human lung cancer cells was examined in different temperature and time settings. Cell viability was quantified by both an MTS assay and reculturing. Fatal conditions evaluated by reculturing were as follows: thermal treatment at 55°C for 5 minutes, 53°C for 10 minutes, and 51°C for 15 minutes. The MTS assay study suggested that thermal treatment at 59°C for 5 minutes and 57°C for 20 minutes showed a severe cytotoxic effect. In vivo study: nude mouse subcutaneous NCI-H460 human lung cancer xenograft models were used for the study. Saline or 0.5 g/L of ICG was injected topically into the tumor (n=3/group). Tumors were irradiated with a laser at 500 mW for 10 minutes. Although the tumor diameter reached 1 cm within 24 days after treatment in all 3 mice using saline/laser, tumor sizes were gradually reduced in all 3 mice using the ICG/laser. In 2 of the 3 mice using ICG/laser, tumors had disappeared macroscopically. The efficacy of the photothermal ablation therapy by low-power near-infrared laser and a topical injection of ICG was clarified using a mouse subcutaneous a lung cancer xenograft model.
    No preview · Article · Apr 2015 · Journal of Bronchology and Interventional Pulmonology
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    ABSTRACT: In aortic arch surgery, we reconstruct branches before opening the arch to avoid cerebral embolism of the debris derived from the aortic wall. We made a trifurcated graft for branch reconstruction using 10 mm and 8 mm polyester grafts. Cardiopulmonary bypass started under right axillary perfusion and venous drainage through the right atrium. While cooling, the left subclavian artery was clamped andanastomosed to the end of the trifurcated graft. Then the ascending aorta was cross-clamped and cardioplegic solution was infused. At 25 degrees centigrade of the tympanic temperature, the left carotid artery is clamped and anastomosed to the branch of the trifurcated graft with or without perfusion into the left carotid artery. Subsequently the brachiocephalic artery was reconstructed in the same manner. After antegrade cerebral perfusion was established through the trifurcated graft via right axillary perfusion, distal anastomosis of the aortic arch was done with the open distal technique. Graft-graft anasto mosis was followed to reperfuse the lower half of the body. Finally proximal anastomosis was performed to complete total arch replacement. Forty-four patients underwent total arch replacement in this technique. In-hospital mortality was 4.5%. Cerebral infarction occurred in 4.5% of the patients probably due to embolization of the debris derived from the branches of the aortic arch.
    No preview · Article · Mar 2015 · Kyobu geka. The Japanese journal of thoracic surgery
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    ABSTRACT: Maximal graft flow acceleration (max df/dt) determined by transit-time flowmetry (TTFM) in the diastolic phase was assessed as a possible predictor of graft failure in coronary artery bypass patients. Max df/dt was retrospectively measured in 57 in situ left internal thoracic artery grafts. TTFM data were fitted to a 5-polynomial curve, which was derived from the first-derivative curve to measure max df/dt (5-polymial max df/dt). Abnormal TTFM was defined as a mean flow of <15 ml/min, pulsatility index of >5 or diastolic filling ratio of <50%. Postoperative coronary angiography (CAG) or multidetector computed tomography (MDCT) was performed within 1 year after surgery. The grafts were classified into four groups: Normal TTFM/Patent MDCT/CAG (N/P), Normal TTFM/Failing MDCT/CAG (N/F), Abnormal TTFM/Patent MDCT/CAG (Ab-N/P) and Abnormal TTFM/Failing MDCT/CAG graft (Ab-N/F). By TTFM, 34 grafts were normal, 5 of which were occluded on CAG, and 23 grafts were abnormal, six of which were occluded on CAG. There were significant differences in 5-polynomial max df/dt between each group pair (P < 0.05, Mann-Whitney U-test) except for the N/F:Ab-N/P group pair; especially, 5-polynomial max df/dt was significantly lower in the Ab-N/F group compared with the other groups (Ab-N/F: 0.89 ± 0.41 vs N/P: 4.74 ± 3.18, N/F: 2.23 ± 0.65, Ab-N/P: 2.70 ± 1.31 ml/s(2), P < 0.01, Mann-Whitney U-test). The sensitivity and specificity of 5-polynomial max df/dt were, respectively, 72.7 and 80.4% (cut-off value, 1.918 ml/s(2)) for all grafts and 100 and 88.2% (cut-off value, 1.273 ml/s(2)) for abnormal TTFM grafts. The TTFM 5-polymial max df/dt value in the early diastolic phase may be a promising predictor of future graft failure. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
    Preview · Article · Jan 2015 · Interactive Cardiovascular and Thoracic Surgery

  • No preview · Article · Dec 2014 · The American surgeon
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    ABSTRACT: Video-assisted thoracoscopic wedge resection of multiple small, non-visible, and nonpalpable pulmonary nodules is a clinical challenge. We propose an ultra-minimally invasive technique for localization of pulmonary nodules using the electromagnetic navigation bronchoscope (ENB)-guided transbronchial indocyanine green (ICG) injection and intraoperative fluorescence detection with a near-infrared (NIR) fluorescence thoracoscope. Fluorescence properties of ICG topically injected into the lung parenchyma were determined using a resected porcine lung. The combination of ENB-guided ICG injection and NIR fluorescence detection was tested using a live porcine model. An electromagnetic sensor integrated flexible bronchoscope was geometrically registered to the three-dimensional chest computed tomographic image data by way of a real-time electromagnetic tracking system. The ICG mixed with iopamidol was injected into the pulmonary nodules by ENB guidance; ICG fluorescence was visualized by a near-infrared (NIR) thoracoscope. The ICG existing under 24-mm depth of inflated lung was detectable by the NIR fluorescence thoracoscope. The size of the fluorescence spot made by 0.1 mL of ICG was 10.4 ± 2.2 mm. An ICG or iopamidol spot remained at the injected point of the lung for more than 6 hours in vivo. The ICG fluorescence spot injected into the pulmonary nodule with ENB guidance was identified at the pulmonary nodule with the NIR thoracoscope. The ENB-guided transbronchial ICG injection and intraoperative NIR thoracoscopic detection is a feasible method to localize multiple pulmonary nodules. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
    No preview · Article · Nov 2014 · The Annals of Thoracic Surgery

  • No preview · Article · Oct 2014 · Journal of the American College of Surgeons
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    ABSTRACT: Purpose: When performing coronary artery bypass grafting, anastomotic insufficiency needs to be detected during surgery. We developed a novel indocyanine green angiography system, the HyperEye Medical System (HEMS), which enables color imaging of the bypass flow. This article described the accuracy of HEMS angiography for predicting graft patency. Methods: A total of 144 grafts in 40 coronary artery bypass grafting patients were assessed by HEMS angiography, a transit time flowmeter (TTF) during surgery and fluoroscopic angiography 1 year after the operation. Results: HEMS angiography showed normal flow in 133 grafts, but abnormal flow in 11. Fluoroscopic angiography showed that 130 of the 133 "normal" grafts were patent (negative predictive value: 97.7%) and that nine of the 11 "abnormal" grafts were occluded (positive predictive value: 81.8%). As a result, 134 grafts were assessed as normal and 10 as abnormal by TTF. Fluoroscopic angiography showed that 124 of these 134 grafts were patent (negative predictive value: 92.5%), whereas two of the 10 grafts were occluded (positive predictive value: 20.0%). For the 127 grafts with compatible results by the HEMS and TTF assessments, the positive and negative predictive values were 100 and 97.6%, respectively. Conclusion: HEMS angiography of a bypass graft may provide an accurate prediction of the graft patency after surgery.
    No preview · Article · Aug 2014 · Surgery Today
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    ABSTRACT: Background: We have developed a novel method of measuring spinal cord-evoked potentials with stimulation and recording at the intercostal nerves (transintercostal-evoked spinal cord potential: Tic-ESCP). The purpose of this study was to examine the feasibility and accuracy of Tic-ESCP during thoracic aortic surgery. Methods: In addition to the conventional electrodes (cranial and intrathecal), stimulating and recording electrodes were placed on the intercostal nerves that were located at a cephalad and caudal level relative to the aneurysm after the pleura on the intercostal nerves was opened. Specially designed hook-type electrodes were anchored to the nerves and surroundings atraumatically and fixed on the pleura. The conventional transcranial motor-evoked potential (Tc-MEP) and Tic-ESCP were recorded simultaneously. Eight patients were examined in this study. Results: In all patients, Tic-ESCP could be clearly recorded with biphasic waveforms consisting of first a positive wave and a subsequent negative wave. In all 8 patients, the waveform of Tc-MEP and Tic-ESCP changed during aortic reconstruction. In 2 cases, the waveform of Tc-MEP and Tic-ESCP decreased below 50% of baseline during aortic clamping and the intercostal arteries were reconstructed with no resultant spinal cord injury. In 1 case with a shaggy aorta, Tc-MEP and Tic-ESCP had different values and each evoked potential could have reflected that regional spinal cord infarction and paraplegia had occurred. Conclusions: Tic-ESCP was clinically feasible and changes were compatible with the conventional Tc-MEP. The Tic-ESCP waveforms were simple and appeared to be specific to the spinal cord within the target range, in contrast to the other evoked potentials which are multimorphic and reflect the amplitudes at the brain and multiple levels of the spinal cord.
    No preview · Article · May 2014 · Annals of Vascular Surgery
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    ABSTRACT: We report two cases of graft migration during open stent grafting, detected by transesophageal echocardiography (TEE). The incidence was 3.7% in our series. The length of landing zone was reduced from 45 mm to 25 mm in case 1 and from 50 mm to 22 mm in case 2 before chest closure. Aneurysmal protrusion on the greater curvature with thin mural thrombus were findings common in both cases. Although additional intervention was not done based on the TEE findings of no endoleak and thrombus formation in the aneurysm, and postoperative course was uneventful, meticulous imaging check-up was needed.
    No preview · Article · Apr 2014 · Annals of Vascular Diseases
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    ABSTRACT: In the treatment for pacemaker infection, removal of infected devices and intensive antibiotics therapy are in principle and new devices should be implanted apart from the infected site. However, there are some problems in the case of children:it is not easy to remove infected devices because epicardial leads are often used for them. If endocardial leads are chosen as a new system, extension of the lead would be concerned with their growth. We report a pediatric case of infection of pacemaker using epicardial leads. It was difficult to cure infection by repeated local treatment leaving epicardial leads and antibiotics therapy was obliged to continue for 9 years to keep infection under control. After growing up, we implanted endocardial leads for her and removed infected devices to cure infection completely.
    No preview · Article · Feb 2014 · Kyobu geka. The Japanese journal of thoracic surgery
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    ABSTRACT: Real-time graft flow assessment in the operative field has been performed to ascertain the patency in coronary artery bypass grafting (CABG). This study aims to evaluate the efficacy of graft flow assessment by epigraftic ultrasonography. CABG was performed in 135 patients from January 2010 to December 2012. One hundred and ten patients (81.4%) underwent both real-time graft flow measurement using epigraftic ultrasonography and coronary angiography (CAG) with a total of 249 grafts. Parameters were obtained from flow velocity curves in all grafts. The grafts were divided into two groups: patent grafts (Group A) and failing grafts (Group B). All parameters were compared in these two groups. Logistic regression analysis was performed to detect the predictors of graft failure and receiver operating characteristic (ROC) curve analysis was used to calculate the optimal cut-off value of the predictors of graft failure. The overall patency as measured by CAG of the grafts was 97.2% (242/249). Logistic regression analysis revealed that the percentage of systolic and diastolic reverse flow (%sRF, %dRF) as well as the pulsatility index (PI) were predictors of early postoperative graft failure. ROC curve analysis revealed that mean velocity <12.5 cm/s, %sRF >9.3%, %dRF >4.1% and PI >4.4 were predictors of early graft failure. In this series, epigraftic ultrasonography depicted graft flow clearly. Epigraftic ultrasonography is a useful tool to predict graft failure during CABG. This technique is easily performed using a conventional linear ultrasound transducer.
    No preview · Article · Jan 2014 · European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery
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    ABSTRACT: Here we report the case of a 68-year-old woman who presented with shortness of breath. Respiratory function tests showed a slightly obstructive physiology. Computed tomography (CT) revealed an aberrant left subclavian artery and a Kommerell diverticulum arising from a right-sided aortic arch that was compressing the trachea and surrounding tissues. A median sternotomy was performed with the patient under circulatory arrest with moderate hypothermia, and a trans-aortic stent graft was inserted to exclude the Kommerell diverticulum. The aberrant left subclavian artery was ligated and an axillo-axillar bypass was constructed. Postoperative CT showed complete exclusion of the Kommerell diverticulum without an endoleak. The patient's breathing difficulty resolved and she was discharged uneventfully. This procedure should be considered as an alternative strategy for exclusion of Kommerell diverticulum.
    No preview · Article · Dec 2013 · Annals of Vascular Surgery
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    ABSTRACT: A calcified amorphous tumor (CAT) is a rare intracardiac mass that carries a risk of embolism. We herein present the case of a club-shaped CAT that originated from the calcified mitral annulus. Echocardiography indicated a pendular motion of the mass and repeated entrapment by a stenotic aortic valve that was sustained for several beats, mimicking a chameleon's tongue. An emergency operation was performed because of the risk of embolism, as well as potential progression of cardiac failure due to worsening aortic valve stenosis. The histological findings were consistent with the diagnosis of a CAT. This report describes a case of an intracardiac tumor that showed unique motion like a chameleon's tongue.
    No preview · Article · Aug 2013 · Surgery Today
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    ABSTRACT: This study tested to see if trehalose, a cytoprotective disaccharide, protects against spinal cord ischemia in a rabbit model. The infrarenal aorta was mobilized in four groups of 10 rabbits. In groups I, II, and III, it was clamped proximally and distally for 20 minutes. In group I, the clamped aorta was infused at 2.5 L/min for 2 hours with lactated Ringer's (LR) solution. In group II, the clamped aorta was infused with 5% trehalose in LR. LR was administered intravenously (2.0 mL/min) in groups I and II starting 30 minutes before clamping. In group III, 5% trehalose in LR was infused intravenously only. Group IV was a sham-operated control group without aortic clamping. At 8, 24, and 48 hours after reperfusion, hind limb function was scored using the Tarlov score (paralysis = 0, perceptible joint movement = 1, good joint movement but unable to stand = 2, able to walk = 3, normal = 4). Histologic analysis and electron microscopy were performed on anterior horn cells. The Tarlov scores in groups I, II, and III were, respectively, 1.1 ± 1.4, 3.5 ± 0.5, and 2.9 ± 0.9 at 8 hours; 0.8 ± 1.2, 3.9 ± 0.3, and 2.9 ± 0.9 at 24 hours; and 0.6 ± 0.7, 3.9 ± 0.3, and 2.7 ± 0.9 at 48 hours after reperfusion. Group IV scores were normal (4 ± 0) at all assessments. These scores were higher in groups II and III than in group I (P < .01) at all assessments. Scores at 24 and 48 hours were higher in group II than in group III (P < .05). In group III, delayed paraparesis developed in one rabbit at 24 hours and in two more at 48 hours. Histopathologic analysis showed the number of normal neurons was higher in groups II (P < .0001), III (P = .006), and IV (P < .0001) vs group I. Electron microscopy confirmed preserved neuronal cell ultrastructure in rabbits with normal limb function. Transaortic trehalose infusion was protective against paraplegia, whereas intravenous trehalose reduced spinal cord ischemia. This study was preliminary and further studies are needed.
    No preview · Article · Aug 2013 · Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter

Publication Stats

2k Citations
393.31 Total Impact Points


  • 2012-2015
    • Kochi University
      • • Department of Surgery
      • • Division of Surgery II
      Kôti, Kōchi, Japan
  • 2011-2014
    • Kochi Medical School
      Kôti, Kōchi, Japan
  • 1987-2013
    • Hiroshima University
      • • Department of Surgery
      • • Department of Cardiovascular Surgery
      • • School of Medicine
      Hirosima, Hiroshima, Japan
  • 2005
    • Showa General Hospital
      Edo, Tōkyō, Japan