Design of Steerable Endoscopes to Improve the Visual Perception of Depth During Laparoscopic Surgery

2004 ◽  
Vol 126 (1) ◽  
pp. 2-5 ◽  
Author(s):  
Paul Breedveld ◽  
Shigeo Hirose
Keyword(s):  
Laparoscopic Surgery ◽  
Visual Perception ◽  
Abdominal Wall ◽  
Visual Feedback ◽  
Degrees Of Freedom ◽  
Bending Stiffness ◽  
Small Incision ◽  
Torsion Stiffness ◽  
4 Degrees Of Freedom

Visual feedback during laparoscopic surgery is provided by an endoscope with a camera that is inserted through a small incision in the abdominal wall. The incision restricts the endoscope movements to 4 degrees of freedom (DOF), making it impossible to observe organs from different sides. This paper describes two 6 DOF steerable endoscopes that contain a new spatial parallelogram-mechanism to transform the handgrip movements into movements of the steerable tip. Part of the mechanism is a new kind of spring that combines high torsion stiffness with a low bending stiffness. The endoscopes and the spring have been applied for two international patents.

scholarly journals Steerable Laparoscopic Cable-Ring Forceps

2010 ◽  
Vol 4 (2) ◽  
Author(s):  
Paul Breedveld
Keyword(s):  
Laparoscopic Surgery ◽  
Abdominal Wall ◽  
Degrees Of Freedom ◽  
Manual Control ◽  
The Future ◽  
Ring Mechanism ◽  
4 Degrees Of Freedom

Laparoscopic surgery is carried out using long and slender endoscopes and instruments that are inserted through small incisions in the abdominal wall. Current endoscopes and instruments are rigid and have the drawback that their motion is restricted to 4-degrees of freedom (DOF). This paper describes a 6-DOF steerable laparoscopic grasping forceps incorporating a novel and very simple “cable-ring” mechanism consisting out of a ring of cables surrounded by two coil springs. Methods are described to increase stiffness and to improve manual control, resulting in a well-working prototype suitable for commercialization. The paper ends with a discussion on a number of cable-ring variants suitable for challenging new steerable designs in the future.

FORCE CHARACTERISTICS AND EFFECTIVE STOPPING UPON THE ABDOMINAL WALL IS PENETRATED OUT BY TROCAR DURING LAPAROSCOPIC SURGERY

2018 ◽  
Vol 18 (03) ◽  
pp. 1850025
Author(s):  
JUNPENG SUN ◽  
KOTARO TADANO
Keyword(s):  
Laparoscopic Surgery ◽  
Abdominal Wall ◽  
Degrees Of Freedom ◽  
Medical Negligence ◽  
Two Degrees Of Freedom ◽  
Experimental Platform ◽  
Trocar Insertion ◽  
Insertion Device ◽  
Injury Patient ◽  
Force Characteristics

Overshooting during trocar insertion may injury patient viscera and arteries or even lead to death. It has been extensively cited as a kind of common medical negligence. Hence, this paper investigated the force characteristics during a trocar inserted into the abdominal wall and developed strategies for effective stopping upon the trocar penetrated out of the abdominal wall. First, an experimental platform with two degrees of freedom was assembled. Second, two insertion methods were compared and the insertion forces using three types of trocars were measured respectively. Subsequently, we interpreted the force characteristics in terms of insertion principle and the abdominal structure. And based on the force characteristics, we generated two algorithms for the two insertion methods, which can be utilized to stop inserting effectively upon the trocar penetrated out of the abdominal wall. Finally, we evaluated the merits and demerits of the two algorithms. This paper proposed the interpretation of force characteristics during trocar insertion and achieved effective stopping to avoid overshooting. It provides foundations for the development of automatic trocar insertion device in the future.

KeyLoop: Mechanical Retraction of the Abdominal Wall for Gasless Laparoscopy

2021 ◽  
pp. 155335062110310
Author(s):  
Aryaman Gupta ◽  
Erin Brown ◽  
Joseph T. Davis ◽  
John Sekabira ◽  
Nimmi Ramanujam ◽  
...  
Keyword(s):  
Laparoscopic Surgery ◽  
Abdominal Wall ◽  
Degrees Of Freedom ◽  
Structural Integrity ◽  
Permanent Deformation ◽  
Load Testing ◽  
Gasless Laparoscopy ◽  
Element Analysis ◽  
Middle Income ◽  
Lifting System

Background. Despite favorable outcomes of laparoscopic surgery in high-income countries, its implementation in low- and middle-income countries (LMICs) is challenging given a shortage of consumable supplies, high cost, and risk of power outages. To overcome these barriers, we designed a mechanical retractor that provides vertical tension on the anterior abdominal wall. Methods. The retractor design is anatomically and mathematically optimized to provide exposure similar to traditional gas-based insufflation methods. Anatomical data from computed tomography scans were used to define retractor size. The retractor is constructed of biocompatible stainless steel rods and paired with a table-mounted lifting system to provide 5 degrees of freedom. Structural integrity was assessed through finite element analysis (FEA) and load testing. Functional testing was performed in a laparotomy model. Results. A user guide based on patient height and weight was created to customize retractor size, and 4 retractor sizes were constructed. FEA data using a 13.6 kg mass (15 mm Hg pneumoperitoneum) show a maximum of 30 mm displacement with no permanent deformation. Physical load testing with applied weight from 0 to 13.6 kg shows a maximum of 60 mm displacement, again without permanent deformation. Retraction achieved a 57% larger field of view compared to an unretracted state in a laparotomy model. Conclusions. The KeyLoop retractor maintains structural integrity, is easily sterilized, and can be readily manufactured, making it a viable alternative to traditional insufflation methods. For surgeons and patients in LMICs, the KeyLoop provides a means to increase access to laparoscopic surgery.

Remapping Hand Movements in a Novel Geometrical Environment

2005 ◽  
Vol 94 (6) ◽  
pp. 4362-4372 ◽  
Author(s):  
Kristine M. Mosier ◽  
Robert A. Scheidt ◽  
Santiago Acosta ◽  
Ferdinando A. Mussa-Ivaldi
Keyword(s):  
Nervous System ◽  
Visual Perception ◽  
Euclidean Space ◽  
Visual Feedback ◽  
Degrees Of Freedom ◽  
Motor Coordination ◽  
Hand Movements ◽  
Data Glove ◽  
Extended Practice ◽  
Final Error

The issue of how the Euclidean properties of space are represented in the nervous system is a main focus in the study of visual perception, but is equally relevant to motor learning. The goal of our experiments was to investigate how the properties of space guide the remapping of motor coordination. Subjects wore an instrumented data glove that recorded the finger motions. Signals generated by the glove operated a remotely controlled endpoint: a cursor on a computer monitor. The subjects were instructed to execute movements of this endpoint with controlled motions of the fingers. This required inverting a highly redundant map from fingers to cursor motions. We found that 1) after training with visual feedback of the final error (but not of the ongoing cursor motion), subjects learned to map cursor locations into configurations of the fingers; 2) extended practice of movement led to more rectilinear cursor movement, a trend facilitated by training under continuous visual feedback of cursor motions; 3) with practice, subjects reduced motion in the degrees of freedom that did not contribute to the movements of the cursor; 4) with practice, subjects reduced variability of both cursor and hand movements; and 5) the reduction of errors and the increase in linearity generalized beyond the set of movements used for training. These findings suggest that subjects not only learned to produce novel coordinated movement to control the placement of the cursor, but they also developed a representation of the Euclidean space on which hand movements were remapped.

scholarly journals Development and assessment of a telesonography system for musculoskeletal imaging

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Mohammed Obaid ◽  
Qianwei Zhang ◽  
Scott J. Adams ◽  
Reza Fotouhi ◽  
Haron Obaid
Keyword(s):  
Degrees Of Freedom ◽  
Ultrasound Images ◽  
Ultrasound Probe ◽  
Rural And Remote ◽  
Significant Delay ◽  
Remote Communities ◽  
Internet Connection ◽  
Good For ◽  
4 Degrees Of Freedom

Abstract Background Telesonography systems have been developed to overcome barriers to accessing diagnostic ultrasound for patients in rural and remote communities. However, most previous telesonography systems have been designed for performing only abdominal and obstetrical exams. In this paper, we describe the development and assessment of a musculoskeletal (MSK) telesonography system. Methods We developed a 4-degrees-of-freedom (DOF) robot to manipulate an ultrasound probe. The robot was remotely controlled by a radiologist operating a joystick at the master site. The telesonography system was used to scan participants’ forearms, and all participants were conventionally scanned for comparison. Participants and radiologists were surveyed regarding their experience. Images from both scanning methods were independently assessed by an MSK radiologist. Results All ten ultrasound exams were successfully performed using our developed MSK telesonography system, with no significant delay in movement. The duration (mean ± standard deviation) of telerobotic and conventional exams was 4.6 ± 0.9 and 1.4 ± 0.5 min, respectively (p = 0.039). An MSK radiologist rated quality of real-time ultrasound images transmitted over an internet connection as “very good” for all telesonography exams, and participants rated communication with the radiologist as “very good” or “good” for all exams. Visualisation of anatomic structures was similar between telerobotic and conventional methods, with no statistically significant differences. Conclusions The MSK telesonography system developed in this study is feasible for performing soft tissue ultrasound exams. The advancement of this system may allow MSK ultrasound exams to be performed over long distances, increasing access to ultrasound for patients in rural and remote communities.

scholarly journals Annular Defects Impair the Mechanical Stability of the Intervertebral Disc

2021 ◽  
pp. 219256822110060
Author(s):  
Jun-Xin Chen ◽  
Yun-He Li ◽  
Jian Wen ◽  
Zhen Li ◽  
Bin-Sheng Yu ◽  
...  
Keyword(s):  
Intervertebral Disc ◽  
Degrees Of Freedom ◽  
Mechanical Stability ◽  
Biomechanical Testing ◽  
Bending Stiffness ◽  
Biomechanical Study ◽  
Torsional Stiffness ◽  
P Value ◽  
Lateral Bending ◽  
Flexion Extension

Study Design: A biomechanical study. Objectives: The purpose of this study was to investigate the effects of cruciform and square incisions of annulus fibrosus (AF) on the mechanical stability of bovine intervertebral disc (IVD) in multiple degrees of freedom. Methods: Eight bovine caudal IVD motion segments (bone-disc-bone) were obtained from the local abattoir. Cruciform and square incisions were made at the right side of the specimen’s annulus using a surgical scalpel. Biomechanical testing of three-dimensional 6 degrees of freedom was then performed on the bovine caudal motion segments using the mechanical testing and simulation (MTS) machine. Force, displacement, torque and angle were recorded synchronously by the MTS system. P value <.05 was considered statistically significant. Results: Cruciform and square incisions of the AF reduced both axial compressive and torsional stiffness of the IVD and were significantly lower than those of the intact specimens ( P < .01). Left-side axial torsional stiffness of the cruciform incision was significantly higher than a square incision ( P < .01). Neither incision methods impacted flexional-extensional stiffness or lateral-bending stiffness. Conclusions: The cruciform and square incisions of the AF obviously reduced axial compression and axial rotation, but they did not change the flexion-extension and lateral-bending stiffness of the bovine caudal IVD. This mechanical study will be meaningful for the development of new approaches to AF repair and the rehabilitation of the patients after receiving discectomy.

scholarly journals Automatic positioning of surgical instruments during laparoscopic surgery with robots using automatic visual feedback

2002 ◽  
Vol 12 ◽  
pp. 75-83
Author(s):  
A. Krupa ◽  
M. de Mathelin ◽  
C. Doignon ◽  
J. Gangloff ◽  
G. Morel ◽  
...  
Keyword(s):  
Laparoscopic Surgery ◽  
Visual Feedback ◽  
Surgical Instruments ◽  
Automatic Positioning

scholarly journals A Case of Traumatic Abdominal Wall Hernia Repaired by Laparoscopic Surgery

2019 ◽  
Vol 80 (10) ◽  
pp. 1882-1887
Author(s):  
Hirohiko SATO ◽  
Daichi ISHIKAWA ◽  
Tsuyoshi TOYOTA ◽  
Kazuhito TAKAMURA ◽  
Murato MIURA
Keyword(s):  
Laparoscopic Surgery ◽  
Abdominal Wall ◽  
Abdominal Wall Hernia ◽  
Traumatic Abdominal Wall Hernia
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