Kenichi Sudo

Prognosis of aortic intramural hemorrhage compared with classic aortic dissection

Aortic intramural hemorrhage occurs fairly frequently among patients with aortic dissection, and may not have a poor prognosis if it is Stanford type B. In patients with type A aortic dissection, cardiac tamponade should be ruled out during observation.

Multiple ulcers with perforation of the small intestine in buerger's disease: a case report.

We present the case of a young man with Buergers disease that involved the gastrointestinal tract. The patient experienced sudden onset of abdominal pain during the period of treatment for peripheral manifestations. Radiographic workup revealed free air in the abdomen. A laparotomy was performed, and the resected specimen revealed regularly distanced and multiple ulcers in proximity of the perforation, which was accompanied by occluded intramural arteries of the small intestine. Although visceral localization of Buergers disease is unusual, several cases have been previously reported. Nevertheless, the manifestation of regularly distanced skip intestinal ulcers in Buergers disease is apparently unique. In addition, detailed pathological findings delineated this rare condition.

Development of MR Compatible Surgical Manipulator toward a Unified Support System for Diagnosis and Treatment of Heart Disease

We propose a new concept of a unified system for supporting both surgical treatment and intrasurgical diagnosis of heart diseases, especially ischemic heart disease like myocardial infarction, under a magnetic-resonance-imaging (MRI) environment. In developing the system, we first designed and built a prototype of maneuverable manipulator as a subsystem. We then evaluated MR compatibility of the manipulator by moving its arm tip close to a phantom in the field of view of an open-configuration MR imager. No noticeable deformation, but some signal-to-noise ratio (SNR) deterioration, was observed in the MR images taken during evaluation. It is planned to combine the manipulator with other subsystems and function modules in order to construct an easy-to-use unified support system. This system will then be applied to treat a variety of diseases of organs and tissues in the human body.

Clinical Application of Intermittent Pressure-Augmented Retrograde Cerebral Perfusion

Brain protection is important during aortic arch surgery, especially in patients with cerebral ischemia. We clinically applied the effectiveness of a novel protocol of retrograde cerebral perfusion with intermittent pressure augmentation for brain protection in a canine model, as described in a previous report. Although, in our patient the brachiocephalic artery and left subclavian artery were occluded as a result of aortitis, there was a history of right cerebral infarction, recovery of consciousness, and no neurologic sequelae. Near-infrared oximetry showed recovery of intracranial blood oxygen saturation every time the pressure was augmented.

Clinical efficacy of intermittent pressure augmented–retrograde cerebral perfusion

OBJECTIVEnDuring aortic surgery under hypothermic circulatory arrest, retrograde cerebral perfusion (RCP) is commonly used as a cerebroprotective method to extend the duration of circulatory arrest safely. Kitahori and colleagues described a novel protocol of RCP using intermittent pressure augmented (IPA)-RCP in 2005. The aim of the present study was to determine the clinical effectiveness of this novel protocol.nnnMETHODSnA total of 20 consecutive patients undergoing total replacement of the aortic arch were assigned to a conventional RCP (n = 10) or an IPA-RCP group (n = 10). Cerebral perfusion was provided at a continuous venous pressure of 25 mm Hg in the conventional RCP, and venous pressure was intermittently provided at 20 mm Hg for 120 seconds and at 45 mm Hg for 30 seconds in the IPA-RCP group. The clinical outcomes were compared between the 2 groups. Regional cerebral oxygen saturation (rSO(2)) was measured using near infrared spectroscopy every 10 minutes from the beginning of RCP initiation. To represent the brain oxygen consumption, the decline ratio of rSO(2) was calculated.nnnRESULTSnThere was no surgical mortality or major neurologic complications in either group. The interval from the end of surgery to full wakefulness was significantly shorter in the IPA-RCP group (85 ± 64 minutes) than in the conventional RCP group (310 ± 282 minutes; P < .05). Although the initial rSO(2) value did not show significant difference in both groups, the rSO(2) with IPA-RCP was greater than that with conventional RCP from 10 to 70 minutes (P < .05). The decline ratio of rSO(2) was lower in the IPA-RCP group than in the RCP perfusion group at all points (P < .05).nnnCONCLUSIONSnIPA-RCP might provide more homogenous cerebral perfusion and a more effective oxygen supply to the brain with better clinical results than conventional RCP.

A prototype master-slave system consisting of two MR-compatible manipulators with interchangeable surgical tools: part of a unified support system for diagnosis and treatment

A prototype master-slave system consisting of two MR-compatible manipulators with interchangeable surgical tools was designed, implemented, and evaluated. The manipulators are designed so as to fit into vertical-magnetic-field open-configuration MR imagers. They are also designed so that the surgical tool mounted at the tip of their arm is interchangeable. The MR compatibility of the manipulator including a surgical tool was evaluated by moving it close to a phantom in the field of view of an open-configuration MR imager. No noticeable deformation, but deterioration in the signal-to-noise ratio of approximately 10 percent, was observed in the MR images. Consulted clinicians then evaluated the manipulability of the master-slave system by maneuvering a pair of slave manipulators through an operation input device consisting of a pair of master manipulators. After several minutes of trial and error, they could perform each primitive motion for suturing tasks on training material mimicking human tissue.

Total aortic arch replacement under intermittent pressure-augmented retrograde cerebral perfusion

Kitahori, Kawata, Takamoto et al. described the effectiveness of a novel protocol for retrograde cerebral perfusion that included intermittent pressure augmentation for brain protection in a canine model. Based on their report, we applied this novel technique clinically. Although the duration of circulatory arrest with retrograde cerebral perfusion was long, the patient recovered consciousness soon after the operation and had no neurological deficit. Near-infrared oximetry showed recovery of intracranial blood oxygen saturation every time the pressure was augmented.

An MR-compatible master-slave manipulator with interchangeable surgical tools.

Abstract This paper describes design, implementation and evaluation of a prototype of magnetic resonance (MR)-compatible master–slave manipulator with interchangeable surgical tools. The manipulator is designed so as to fit vertical-magnetic-field open-configuration MR imagers. Also, it is designed so that the surgical tool at the arm tip is interchangeable. We evaluated MR compatibility of the manipulator including a surgical tool by moving it close to a phantom in the field of view of an open-configuration MR imager. No noticeable deformation, but some signal-to-noise ratio (SNR) deterioration, was observed in the MR images. Consulted clinicians then evaluated its manipulability by maneuvering the master–slave manipulator system. After several-minute trial and error, they could perform each primitive motion for suturing task to training materials.

Intra-operative guidance with real-time information of open MRI and manipulators using coordinate-integration module

Assuming the surgery under open magnetic resonance imaging (MRI) equipment with manipulators, we developed the coordinate-integration module and the real-time functions that could display the manipulators position on the volume data of MRI and could obtain the cross-section images of MRI at the manipulators position. The small field of view from an endoscope is the problem in most of the minimally invasive surgeries with manipulators. Therefore, we propose an endoscopic surgery with manipulators under open MRI equipment. The coordinate-conversion parameters were calculated in the coordinate-integration module by calibration with an optical tracking system and markers. The delay of the manipulator-position display on the volume data was approximately within 0.5 second though it depended on the amount of the volume data. We could also obtain the cross-section images of MRI at the manipulators position using the information from the coordinate-integration module. With these functions, we can cope with the change of the organ shape during surgery with the guidance based on the individual information. Furthermore, we can use the manipulator as an MRI probe to define cross-section position like an ultrasonic probe.

Equine pericardial roll graft replacement of infected pseudoaneurysm of the aortic arch

Resection of the infected aorta, debridement of the surrounding tissue, in situ graft replacement, and omentopexy is the standard procedure for treating infected aortic aneurysms, but the question of which graft material is optimal is still a matter of controversy. We recently treated a patient with an infected thoracic aortic aneurysm. The aneurysm was located in the proximal aortic arch. Because the patients had previously undergone abdominal surgery, the aortic arch were replaced in situ with a branched equine pericardial roll grafts. The patient is alive and well 23u2009months after the operation.