Clinical impact of systematic pelvic and para-aortic lymphadenectomy for pT1 and pT2 ovarian cancer: a retrospective survey by the Sankai Gynecology Study Group.

BACKGROUND: The therapeutic value of systematic lymphadenectomy for early-stage epithelial ovarian cancer (EOC) is controversial. This study evaluates the survival impact and adverse events of systematic pelvic and para-aortic lymphadenectomy in patients with pT1 and pT2 EOC. METHODS: A retrospective investigation was performed using data from patients with pT1 and pT2 EOC at multi-institutions belonging to the Sankai Gynecologic Study Group (SGSG). We selected patients who had undergone systematic pelvic and para-aortic lymphadenectomy (Group LA) (n = 284) and patients who had not undergone lymph node resection (Group no-LA) (n = 138). Outcomes for patients and peri-operative adverse events were compared between the two groups. RESULTS: The median operation time was significantly longer in Group LA (288 min) than in Group no-LA (128 min) (P < 0.0001). Total blood loss was significantly higher in Group LA, 43.7 % of patients receiving blood transfusions. There were no significant differences between the treatment groups for progression-free survival (PFS) or overall survival (OS). However, for patients with pT2, PFS was significantly longer in Group LA than in Group no-LA (P = 0.0150). Lymph node metastases were detected in 23 cases (8.1 %) and these patients had significantly shorter PFS than those without metastasis (P = 0.0409). The outcome for patients who underwent chemotherapy after surgery was significantly improved in the Group no-LA, but no improvement was observed in Group LA. CONCLUSIONS: Systematic lymphadenectomy may improve outcomes only in pT2 EOC patients with acceptable peri-operative events. Furthermore, accurate surgical staging may avoid unnecessary adjuvant chemotherapy in selected early-stage cases.

Quantitative evaluation of upper limb ataxia in spinocerebellar ataxias.

OBJECTIVE: To quantitatively evaluate upper limb ataxia using a novel pen-like sensor device in patients with spinocerebellar ataxia (SCA) and to assess its validity, reliability, and sensitivity to disease progression. METHODS: We designed a cross-sectional and longitudinal study of patients with SCA and healthy controls. Upper limb ataxia was evaluated using a device that measures the three-dimensional position every 10 msec. Participants were instructed to move a pen-like part of the device iteratively between two buttons. We evaluated the time, length, velocity, and variation coefficient of the stroke, and calculated the distortion index using the mean squared error. The following scales were also evaluated: Scale for the Assessment and Rating of Ataxia (SARA), the International Cooperative Ataxia Rating Scale (ICARS), and the nine-hole pegboard test. Subjects were followed 12 months after the baseline evaluation. RESULTS: A total of 42 patients with SCA and 33 healthy controls were enrolled and evaluated. For all ataxia indices measured using the device there were significant differences between healthy controls and patients with SCA. Among the ataxia indices, the distortion index showed the strongest correlation with the SARA and ICARS upper limb score (Pearson's r = 0.647 and 0.722, respectively). Test-retest reliability was high for most of the ataxia indices. In the longitudinal analysis, the distortion index showed high standardized response mean and adjusted effect size, regardless of disease severity. INTERPRETATION: Our study demonstrated that the distortion index is a reliable functional marker that is sensitive to longitudinal change in patients with SCA.

Evaluation of the characteristics of various types of coils for the embolization of intracranial aneurysms with an optical pressure sensor system.

INTRODUCTION: In coil embolization for an intracranial aneurysm, it is important to appropriately choose the coil most suitable for coping with various unforeseen situations. Additionally, because dense coil packing of the aneurysm sac is the most important factor to avoid a recurrence, properly selecting the coil is essential. In this article, the authors measured the coil insertion pressure of various types of coils with a newly developed sensor system, and coil characteristics were investigated. METHODS: The sensor consists of a hemostatic valve connected to the proximal end of a microcatheter. The sensor principle is based on an optical system. Using this, an experimental silicone aneurysm embolization was performed automatically at constant speed. The pattern of the insertion pressure and the maximum insertion pressure (MIP) were analyzed for the various types of coils. The sensor continuously monitored the mechanical force during the insertions. RESULTS: The sensor adequately recorded the coil insertion pressure during embolization in each coil. MIP was generally ranked in order of the coil type. The soft type coils required relatively less insertion pressure than standard/helical and 3D type. As for the patterns of coil insertion pressure, each coil presented a saw-like pressure pattern, though we observed some slight differences. 3D type coils showed peak pressure at the moment of "painting". Coil loop diameters barely affected MIP. However, as to the patterns of pressure, larger size coils more often presented the peak. CONCLUSIONS: Coil characteristics were well evaluated. The results obtained here reflected some actual clinical experience. Furthermore, collecting the in vivo study is mandatory, which may provide clinically useful data.

Measurement of inserting motion of bladeless trocar at real surgery for development of a virtual training system for initial trocar placement in laparoscopic surgery.

BACKGROUND/AIMS: The optical view method is an alternative to the open method as a laparoscopic entry technique, but it calls for a certain experience. Therefore we undertook the development of a training system for optical view method in initial trocar placement. For this purpose, kinetic data concerning insertion of a trocar were measured by means of non-invasive monitoring during actual surgery. METHODOLOGY: We slotted force and motion sensors into an adapted trocar and measured the kinetic aspects of trocar insertion in terms of force and torque. The measurement was carried out at the time of the second and third trocar insertion by a single experienced surgeon. RESULTS: The measurement was carried out at 11 sites in 6 patients. We measured position, inserting force and inserting torque of the measuring trocar continuously. Mean maximum inserting force was 71.4N (range: 63.9-75.5N) at the perinavel port and 65.3N (range: 31.8-83.8N) at other sites. Mean maximum torque was 0.19Nm (range: 0.18-0.21Nm) at the perinavel port, and 0.23Nm (0.15-0.35Nm) at other sites. The number of rotations needed to penetrate the abdominal wall differed considerably among the patients. CONCLUSION: In the measurement by an experienced operator, inserting force and torque data were consistent and generally did not depend on the patient characteristics or the site of puncture. Difficulty in penetration according to the physical characteristics of the patients was adjusted by differences in the number of rotations applied to the trocar.

A novel pressure sensor with an optical system for coil embolization of intracranial aneurysms. Laboratory investigation.

OBJECT: In endovascular coil embolization for an intracranial aneurysm, the excessive pressure created during coil insertion into an aneurysm can cause a catastrophic rupture or dislodge a microcatheter tip from the aneurysm dome, resulting in insufficient embolization. Such undue mechanical pressure can only be subjectively detected by the subtle tactile feedback the surgeon experiences. Therefore, the authors of this study developed a new sensor device to measure the coil insertion pressure via an optical system. METHODS: This novel sensor system consists of a hemostatic valve connected to the proximal end of a microcatheter (Y-connector). The sensor principle is based on an optical system composed of a light-emitting diode (LED) and a line sensor. The latter measures how much the coil-delivery wire slightly bends in response to the insertion pressure by detecting the wire shadow. This information is translated into a given force level. Experimental aneurysm embolization was performed using this optical sensor. A silicone aneurysm model and an in vivo model (porcine aneurysm model) were used in this study. Several surgeons manually performed the coil insertions. The sensor continuously monitored the mechanical force during the insertions. RESULTS: The sensor adequately recorded the coil insertion pressure during embolization. The presence of the sensor did not hinder the embolization procedure in any way. During embolization in the silicone aneurysm model, a sinusoid pattern of pressure occurred, reflecting actual clinical experience. Similar results were obtained in the in vivo study. CONCLUSIONS: This new sensor device adequately measures coil insertion pressure. This system provides potentially safer and more reliable aneurysm embolizations.

New objective evaluation method for functional bowel disorder using video capsule endoscopy.

AIM: The aim of the present study was to use video capsule endoscopy (VCE) to objectively evaluate bowel movements in patients with irritable bowel syndrome (IBS) compared with healthy volunteers. METHODS: Subjects were nine healthy volunteers (group A) and five IBS patients (group B) whose VCE reached the cecum within the examination time. As the darkest component in an image of VCE is the lumen, we regarded real movements of the intestine observed in the images as the changes of luminal movement, and analyzed them. We trimmed the luminal edge, counted pixels in the lumen and the low brightness area (LBA), of all VCE images and compared them between the groups. RESULTS: There was no difference in the frequency observed in the LBA corresponding to the luminal area between the groups. As for the average volume of the LBA found in an image, it was 1702 pixels in healthy persons versus 305 in IBS patients (P = 0.21) and in healthy persons it tends to be larger. We drew a graph of LBA by time-course. A periodic change in the volume of LBA was found in eight of nine (88.9%) healthy persons over time, but in only two of five (40.0%) IBS patients (P = 0.62). Using endoscopy, a difference in the bowel movement between groups A and B could be evaluated objectively. CONCLUSION: The present study presents the possibility of a new technique to evaluate functional bowel disorders objectively using an endoscopic procedure.

Sport-specific characteristics of trunk muscles in collegiate wrestlers and judokas.

This study evaluated the sport-specific characteristics of the cross-sectional areas (CSAs) of trunk muscles and trunk muscle strength in wrestlers and judokas. We also examined whether their trunk muscles and muscle strength depended on athletic performance levels in each sport. The subjects comprised 14 male collegiate wrestlers and 14 judokas. Magnetic resonance imaging was used to assess the trunk muscle CSAs at the L3-4 level parallel to the lumbar disc space. A Biodex System3 was used to measure isokinetic trunk flexor and extensor muscle strength of peak torque, work, average torque, and average power. The absolute and relative CSAs of the trunk muscles in the wrestlers and judokas were significantly different (rectus abdominis: wrestling > judo, P < 0.05; obliques: wrestling < judo, P < 0.05; quadratus lumborum: wrestling < judo, P < 0.01). We confirmed that the absolute and relative trunk extensor and flexor strength of peak torque, work, and average torque were significantly higher in the collegiate wrestlers than in judokas. On athletic performance, the tendency of the CSAs and muscular strength of trunk muscles was not consistent with athletic performance levels in each sport. Our findings indicated that the sport-specific characteristics of the CSAs of the trunk muscles and trunk muscle strength obviously differed between the 2 similar sports. Athletes should practice the sport-specific training of trunk muscles and develop sport specificity in their sports. Particularly, wrestlers have to train in trunk flexion and extension motions, and judokas need to strengthen trunk rotation and lateral flexion motions. This information will be available for athletes as well as strength and technical training coaches in wrestling, judo, and the other sports.

Trunk muscle strength and disability level of low back pain in collegiate wrestlers.

INTRODUCTION/PURPOSE: Low back pain (LBP) is a frequent injury in athletes. This study examined the relationship between isokinetic trunk muscle strength and the functional disability level of chronic LBP. We particularly focused on the existence of radiological abnormalities (RA) in the lumbar region. METHODS: Subjects were 53 collegiate wrestlers. Trunk extensor and flexor muscle strength was measured at three angular velocities (60, 90, and 120degrees x s(-1)). The examined parameters for trunk muscle strength were peak torque, work, average torque, and average power. The disability level of LBP was estimated by using two questionnaires. Based on the RA evaluation with x-ray and MRI, all 53 wrestlers were assigned to two groups as the RA group (N = 35, 66%) and the non-RA group (N = 18, 34%). Correlations between trunk muscle strength and the disability level of LBP in each group were analyzed with Spearman's rank test. RESULTS: Without considering the disability level, there were 14 subjects with LBP (40%) in the RA group and 8 (44%) in the non-RA. Significantly correlated parameters with the disability level of LBP could be observed only when the subjects were restricted to the non-RA group. The correlated parameters with the two questionnaires were peak torque at 120degrees x s(-1), work at 60degrees x s(-1) and 90degrees x s(-1), and average torque at 90degrees x s(-1) and 120degrees x s(-1). There were no significantly correlated parameters in the RA group. None of the trunk flexor parameters were significantly correlated with the disability level of LBP. CONCLUSION: The relatively low strength of trunk extensors may be one of the factors related to nonspecific chronic low back pain in collegiate wrestlers.

Surgical bedside master console for neurosurgical robotic system.

PURPOSE: We are currently developing a neurosurgical robotic system that facilitates access to residual tumors and improves brain tumor removal surgical outcomes. The system combines conventional and robotic surgery allowing for a quick conversion between the procedures. This concept requires a new master console that can be positioned at the surgical bedside and be sterilized. METHODS: The master console was developed using new technologies, such as a parallel mechanism and pneumatic sensors. The parallel mechanism is a purely passive 5-DOF (degrees of freedom) joystick based on the author's haptic research. The parallel mechanism enables motion input of conventional brain tumor removal surgery with a compact, intuitive interface that can be used in a conventional surgical environment. In addition, the pneumatic sensors implemented on the mechanism provide an intuitive interface and electrically isolate the tool parts from the mechanism so they can be easily sterilized. RESULTS: The 5-DOF parallel mechanism is compact (17 cm width, 19cm depth, and 15cm height), provides a 505,050 mm and 90° workspace and is highly backdrivable (0.27N of resistance force representing the surgical motion). The evaluation tests revealed that the pneumatic sensors can properly measure the suction strength, grasping force, and hand contact. In addition, an installability test showed that the master console can be used in a conventional surgical environment. CONCLUSION: The proposed master console design was shown to be feasible for operative neurosurgery based on comprehensive testing. This master console is currently being tested for master-slave control with a surgical robotic system.

Neurosurgical robotic system for brain tumor removal.

PURPOSE: Brain tumor (e.g., glioma) resection surgery, representing the first step for many treatments, is often difficult and time-consuming for neurosurgeons. Thus, intelligent neurosurgical instruments have been developed to improve tumor removal. METHODS: The concept and robotic structure of intelligent neurosurgical instruments were introduced. These instruments consist of a surgical robot, a master device and operating software. The robot incorporates a surgical motion base and tool manipulator, including a volume control suction tool. Open Core Control software was developed for connecting intelligent neurosurgical instruments through a network connection and integrating the instruments into a system. RESULTS: Mechanical evaluation tests on the components and a preliminary system evaluation were performed. A phantom model was fixed on a head frame, and a tumor-removal procedure was successfully performed using prototype intelligent neurosurgical instruments. CONCLUSION: Intelligent neurosurgical instruments are feasible and suitable for on-going evaluation in practical tasks, including in-vivo animal testing.

Cartilage intermediate layer protein gene is associated with lumbar disc degeneration in male, but not female, collegiate athletes.

BACKGROUND: The authors previously identified a significant association between lumbar disc degeneration (LDDG) and cartilage intermediate layer protein (CILP) single nucleotide polymorphism (SNP) in collegiate male judokas. HYPOTHESIS: A significant association between LDDG and the CILP SNP is observed in Japanese collegiate athletes. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: The participants were 601 trained collegiate athletes (male, 403; female, 198) from 7 different sports. Lumbar disc degeneration was evaluated using T2-weighted magnetic resonance imaging. Genotyping of the CILP gene (1184T/C) was performed by using DNA sequencing. RESULTS: Among the 601 collegiate athletes, the odds ratio (OR) for the occurrence of LDDG with the CILP C allele was 1.4 (95% confidence interval [CI], 1.05-1.86). By using logistic regression analysis concomitant with the interaction term and the Wald test, the authors found that weight (OR, 1.04; 95% CI, 1.02-1.06), CILP genotype (CT: OR, 2.0; 95% CI, 1.24-3.15; CC: OR, 2.9; 95% CI, 1.09-7.74), and gender (OR, 2.1; 95% CI, 1.21-3.67) were significant risk factors for LDDG. These analyses also indicated that there was no effect of the CILP genotype on LDDG in female athletes. CONCLUSION: The CILP SNP 1184T/C is a risk factor for male collegiate athletes. Information regarding the CILP gene polymorphism may be important for preventing and managing lumbar disc diseases, especially in male athletes.

Development of a real-time tactile sensing system for brain tumor diagnosis.

PURPOSE: Tactile sensing techniques may distinguish tumor from healthy tissue and have potential for intraoperative brain tumor diagnosis. The aim of this study is to develop a biocompatible real-time sensing system to measure tactile information such as softness and smoothness, and its application to brain tumor diagnosis. METHODS: An active tactile sensor is developed using balloon expansion. This compact system provides instantaneous tactile information and has potential for brain tumor diagnosis. Measurements are obtained on soft samples with different stiffness and surface condition with testing of boundary condition influence on thickness and area of the object. Then, measurements on white matter and gray matter of porcine ex vivo brain are done as the first step for brain tumor diagnosis. RESULTS: The sensor can discriminate samples with different stiffness and surface condition subject to influence by boundary conditions. The sensor can evaluate an object relatively under the same boundary conditions but requires enough thickness and area to evaluate absolutely. Measurements on brain show that the sensor can discriminate between white matter and gray matter. CONCLUSIONS: Although the sensor has problems on absolute evaluation, results show that the sensor can evaluate tactile information, and it has potential for brain tumor diagnosis.

Open core control software for surgical robots.

OBJECT: In these days, patients and doctors in operation room are surrounded by many medical devices as resulting from recent advancement of medical technology. However, these cutting-edge medical devices are working independently and not collaborating with each other, even though the collaborations between these devices such as navigation systems and medical imaging devices are becoming very important for accomplishing complex surgical tasks (such as a tumor removal procedure while checking the tumor location in neurosurgery). On the other hand, several surgical robots have been commercialized, and are becoming common. However, these surgical robots are not open for collaborations with external medical devices in these days. A cutting-edge "intelligent surgical robot" will be possible in collaborating with surgical robots, various kinds of sensors, navigation system and so on. On the other hand, most of the academic software developments for surgical robots are "home-made" in their research institutions and not open to the public. Therefore, open source control software for surgical robots can be beneficial in this field. From these perspectives, we developed Open Core Control software for surgical robots to overcome these challenges. MATERIALS AND METHODS: In general, control softwares have hardware dependencies based on actuators, sensors and various kinds of internal devices. Therefore, these control softwares cannot be used on different types of robots without modifications. However, the structure of the Open Core Control software can be reused for various types of robots by abstracting hardware dependent parts. In addition, network connectivity is crucial for collaboration between advanced medical devices. The OpenIGTLink is adopted in Interface class which plays a role to communicate with external medical devices. At the same time, it is essential to maintain the stable operation within the asynchronous data transactions through network. In the Open Core Control software, several techniques for this purpose were introduced. Virtual fixture is well known technique as a "force guide" for supporting operators to perform precise manipulation by using a master-slave robot. The virtual fixture for precise and safety surgery was implemented on the system to demonstrate an idea of high-level collaboration between a surgical robot and a navigation system. The extension of virtual fixture is not a part of the Open Core Control system, however, the function such as virtual fixture cannot be realized without a tight collaboration between cutting-edge medical devices. By using the virtual fixture, operators can pre-define an accessible area on the navigation system, and the area information can be transferred to the robot. In this manner, the surgical console generates the reflection force when the operator tries to get out from the pre-defined accessible area during surgery. RESULTS: The Open Core Control software was implemented on a surgical master-slave robot and stable operation was observed in a motion test. The tip of the surgical robot was displayed on a navigation system by connecting the surgical robot with a 3D position sensor through the OpenIGTLink. The accessible area was pre-defined before the operation, and the virtual fixture was displayed as a "force guide" on the surgical console. In addition, the system showed stable performance in a duration test with network disturbance. CONCLUSION: In this paper, a design of the Open Core Control software for surgical robots and the implementation of virtual fixture were described. The Open Core Control software was implemented on a surgical robot system and showed stable performance in high-level collaboration works. The Open Core Control software is developed to be a widely used platform of surgical robots. Safety issues are essential for control software of these complex medical devices. It is important to follow the global specifications such as a FDA requirement "General Principles of Software Validation" or IEC62304. For following these regulations, it is important to develop a self-test environment. Therefore, a test environment is now under development to test various interference in operation room such as a noise of electric knife by considering safety and test environment regulations such as ISO13849 and IEC60508. The Open Core Control software is currently being developed software in open-source manner and available on the Internet. A communization of software interface is becoming a major trend in this field. Based on this perspective, the Open Core Control software can be expected to bring contributions in this field.