Publications by authors named "Hiroyuki Tsukihara"

Article Synopsis
  • This study addresses the challenges of tracking kidney and liver organs during high-intensity focused ultrasound (HIFU) treatment, as respiratory movements can hinder precise cauterization and risk damage to surrounding tissues.
  • The researchers developed and tested three methods (AEMA, AEMAD, AEMAD++) for estimating organ angles in ultrasound images, using a phantom model to create a dataset by capturing various images of the kidney.
  • AEMAD++ was found to have the best performance in terms of accuracy (29.5%) and processing speed (3.20 FPS), indicating its potential for effective organ tracking in medical applications.
View Article and Find Full Text PDF

Purpose: An inevitable feature of ultrasound-based diagnoses is that the quality of the ultrasound images produced depends directly on the skill of the physician operating the probe. This is because physicians have to constantly adjust the probe position to obtain a cross section of the target organ, which is constantly shifting due to patient respiratory motions. Therefore, we developed an ultrasound diagnostic robot that works in cooperation with a visual servo system based on deep learning that will help alleviate the burdens imposed on physicians.

View Article and Find Full Text PDF

Laparoscopic vision-based ultrasound probe tracking systems have gained considerable attention in ultrasound-guided laparoscopic surgeries as replacements for external tracking systems (e.g. optical tracking and electromagnetic tracking systems), which increase cost and setting time, require additional operation space, and introduce new limitations.

View Article and Find Full Text PDF

Accurate morphological information on aortic valve cusps is critical in treatment planning. Image segmentation is necessary to acquire this information, but manual segmentation is tedious and time consuming. In this paper, we propose a fully automatic aortic valve cusps segmentation method from CT images by combining two deep neural networks, spatial configuration-Net for detecting anatomical landmarks and U-Net for segmentation of aortic valve components.

View Article and Find Full Text PDF

Purpose: Noise-free ultrasound images are essential for organ monitoring during regional ultrasound-guided therapy. When the affected area is located under the ribs, however, acoustic shadow is caused by the reflection of sound from hard tissues such as bone, and the image is output with missing information in this region. Therefore, in the present study, we attempt to complement the image in the missing area.

View Article and Find Full Text PDF

Background: The Japan Cardiovascular Surgery Database (JCVSD) is a nationwide registry of patients undergoing cardiovascular surgery in Japan. To investigate and improve data quality, we have been conducting on-site institutional audits since 2004. This study aimed to investigate the accuracy of the registered data by comparing it to site visit data.

View Article and Find Full Text PDF

Background/aim: We investigated pelvic arterial deformation and shift due to intraoperative pneumoperitoneum and postural changes in an animal model.

Materials And Methods: Computed tomography images of pigs were acquired in different body positions (supine, head down at 5° and 10°, right lateral recumbent at 5° and 15°) before and after insufflation. We used a free software (3D Slicer) for image analysis.

View Article and Find Full Text PDF

Background: Neuroendovascular therapy is now the choice for the management of many neurovascular pathologies, and physicians with endovascular skills are in high demand. In addition to the traditional method of practicing hand movements to learn skills, a new strategy of practicing eye movements to learn skills is also attracting attention. This preliminary study explored the differences in gaze behavior depending on experience with endovascular procedures to be facilitated in future skill training in neuroendovascular therapy.

View Article and Find Full Text PDF

Background: Laparoscopic lateral pelvic lymph node dissection (LPLND) in rectal cancer surgery requires considerable skill because the pelvic arteries, which need to be located to guide the dissection, are covered by other tissues and cannot be observed on laparoscopic views. Therefore, surgeons need to localize the pelvic arteries accurately before dissection, to prevent injury to these arteries.

Methods: This report proposes a surgical navigation system to facilitate artery localization in laparoscopic LPLND by combining ultrasonic imaging and laparoscopy.

View Article and Find Full Text PDF

In the original publication of the article, the values of the row "Norwood procedure", under "(3) Main procedure" in Table 3 were published incorrectly. The corrected part of the table is given in this Correction.

View Article and Find Full Text PDF

The Japan Cardiovascular Surgery Database (JCVSD) was created in 2000 with the support of the Society of Thoracic Surgeons (STS). The STS database content was translated to Japanese using the same disease criteria and in 2001, data entry for adult cardiac surgeries was initiated online using the University Hospital Medical Information Network (UMIN). In 2008, data entry for congenital heart surgeries was initiated in the congenital section of JCVSD and preoperative expected mortality (JapanSCORE) in adult cardiovascular surgeries was first calculated using the risk model of JCVSD.

View Article and Find Full Text PDF

In this study, we aimed to develop a stereoscopic fluorescence camera system for simultaneous evaluation of wall motion and tissue perfusion using indocyanine green (ICG) fluorescence imaging. The system consists of two high-speed stereo cameras, an excitation lamp, and a computer for image processing. Evaluation experiments demonstrated that the stereoscopic fluorescence camera system successfully performed the simultaneous measurement of wall motion and tissue perfusion based on ICG fluorescence imaging.

View Article and Find Full Text PDF

Background: Perioperative risk during coronary artery bypass grafting (CABG) is reportedly high in patients with chronic renal disease. We aimed to determine postoperative mortality and morbidity and identify the perioperative risk factors of mortality during CABG in hemodialysis (HD)-dependent patients.

Methods And Results: From the Japan Adult Cardiovascular Surgery Database, we compared 1,300 HD-dependent chronic renal failure patients with 18,387 non-HD patients who all underwent isolated CABG between January 2005 and December 2008.

View Article and Find Full Text PDF

Background: To develop a new endoscope for performing simple surgical tasks inside the blood-filled cardiac atrium/chamber, that is, "off-pump" cardiac surgeries.

Methods: We developed the endoscope system with plasma flushing and coaxial round jet nozzle. The "plasma flushing" system was invented to observe the interior of the blood-filled heart by displacing blood cells in front of the endoscope tip.

View Article and Find Full Text PDF

Background And Aim Of The Study: Risk models of cardiac valve surgery using a large database are useful for improving surgical quality. In order to obtain accurate, high-quality assessments of surgical outcome, each geographic area should maintain its own database. The study aim was to collect Japanese data and to prepare a risk stratification of cardiac valve procedures, using the Japan Adult Cardiovascular Surgery Database (JACVSD).

View Article and Find Full Text PDF

Objective: While isolated coronary artery bypass grafting (CABG) poses major risks as well as benefits to cardiovascular surgery, procedures such as thoracic aortic surgery and combined CABG surgeries are also important contributors to mortality and morbidity. The objective of this study was to create and validate risk models including high-risk cardiovascular procedures to improve quality.

Methods: The Japan Cardiovascular Surgery Database of patients enrolled cardiovascular surgical patients between January 2005 and December 2007.

View Article and Find Full Text PDF

Background: Although understanding the association between surgical volume and outcome has been the focus of much research, no study has yet reported the volume-outcome effect for thoracic aortic surgery.

Methods: From the clinical database, we identified and analyzed 2875 procedures that took place across 36 centers between 2003 and 2005. The effect of hospital procedural volume was assessed for each outcome measure using a hierarchical mixed-effects logistic regression model.

View Article and Find Full Text PDF

The purpose of this study is to develop a new endoscope for performing simple surgical tasks inside a cardiac atrium/chamber filled with blood, i.e., for performing "off-pump" cardiac surgeries.

View Article and Find Full Text PDF

Background: Risk models of coronary artery bypass grafting (CABG) using a large database are useful for improving surgical quality. To obtain accurate, high-quality assessments of the surgical outcomes, each country should maintain its own database. This study was conducted to collect Japanese data and prepare a risk stratification of isolated CABG procedures using the Japan Adult Cardiovascular Surgery Database (JACVSD).

View Article and Find Full Text PDF