Peter Culmer - Academia.edu (original) (raw)

Papers by Peter Culmer

Research paper thumbnail of Friction characteristics of trocars in laparoscopic surgery

Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine, Jan 30, 2015

This article investigates the friction characteristics of the instrument-trocar interface in lapa... more This article investigates the friction characteristics of the instrument-trocar interface in laparoscopic surgery for varying linear instrument velocities, trocar seal design and material, and trocar tilt. Furthermore, the effect of applying lubrication at the instrument-trocar seal interface on friction was studied. A friction testing apparatus was designed and built to characterise the resistance force at the instrument-trocar interface as a function of the instrument's linear movement in the 12-mm trocar (at constant velocity) for different design, seal material, and angle of tilt. The resistance force depended on the trocar seal design and material properties, specifically surface roughness, elasticity, hardness, the direction of movement, and the instrument linear velocity, and varied between 0.25 and 8 N. Lubricating the shaft with silicone oil reduced the peak resistance force by 75% for all trocars and eliminated the stick-slip phenomenon evident in non-lubricated cases....

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Research paper thumbnail of Neurosurgical patties: adhesion and damage mitigation

Journal of Neurosurgery, 2015

OBJECT Neurosurgical patties are textile pads used during most neurosurgical operations to protec... more OBJECT Neurosurgical patties are textile pads used during most neurosurgical operations to protect tissues, manage the fluid environment, control hemostasis, and aid tissue manipulation. Recent research has suggested that, contrary to their aim, patties adhere to brain tissue and cause damage during removal. This study aimed to characterize and quantify the degree of and consequences resulting from adhesion between neurosurgical patties and brain tissue. METHODS Using a customized peel apparatus, the authors performed 90° peel tests on 5 patty products: Policot, Telfa, Americot, Delicot, and Ray-Cot (n = 247) from American Surgical Company. They tested 4 conditions: wet patty on glass (control), wet patty on wet brain peeled at 5 mm/sec (wet), dry patty on wet brain peeled at 5 mm/sec (dry), and wet patty on wet brain peeled at 20 mm/sec (speed). The interaction between patty and tissue was analyzed using peel-force traces and pre-peel histological analysis. RESULTS Adhesion strength differed between patty products (p < 0.001) and conditions (p < 0.001). Adhesion strength was greatest for Delicot patties under wet (2.22 mN/mm) and dry (9.88 mN/mm) conditions. For all patties, damage at the patty-tissue interface was proportional to the degree of fiber contact. When patties were irrigated, mechanical adhesion was reduced by up to 550% compared with dry usage. CONCLUSIONS For all patty products, mechanical (destructive) and liquid-mediated (nondestructive) adhesion caused damage to neural tissue. The greatest adhesion occurred with Delicot patties. To mitigate patty adhesion and neural tissue damage, surgeons should consider regular irrigation to be essential during neurosurgical procedures.

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Research paper thumbnail of The Cerebral Palsy Kinematic Assessment Tool (CPKAT): feasibility testing of a new portable tool for the objective evaluation of upper limb kinematics in children with cerebral palsy in the non-laboratory setting

Disability and Rehabilitation: Assistive Technology, 2014

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Research paper thumbnail of Vision-based body tracking: turning Kinect into a clinical tool

Disability and Rehabilitation: Assistive Technology, 2014

Abstract Purpose: Vision-based body tracking technologies, originally developed for the consumer ... more Abstract Purpose: Vision-based body tracking technologies, originally developed for the consumer gaming market, are being repurposed to form the core of a range of innovative healthcare applications in the clinical assessment and rehabilitation of movement ability. Vision-based body tracking has substantial potential, but there are technical limitations. Method: We use our "stories from the field" to articulate the challenges and offer examples of how these can be overcome. Results: We illustrate that: (i) substantial effort is needed to determine the measures and feedback vision-based body tracking should provide, accounting for the practicalities of the technology (e.g. range) as well as new environments (e.g. home). (ii) Practical considerations are important when planning data capture so that data is analysable, whether finding ways to support a patient or ensuring everyone does the exercise in the same manner. (iii) Home is a place of opportunity for vision-based body tracking, but what we do now in the clinic (e.g. balance tests) or in the home (e.g. play games) will require modifications to achieve capturable, clinically relevant measures. Conclusions: This article articulates how vision-based body tracking works and when it does not to continue to inspire our clinical colleagues to imagine new applications. Implications for Rehabilitation Vision-based body tracking has quickly been repurposed to form the core of innovative healthcare applications in clinical assessment and rehabilitation, but there are clinical as well as practical challenges to make such systems a reality. Substantial effort needs to go into determining what types of measures and feedback vision-based body tracking should provide. This needs to account for the practicalities of the technology (e.g. range) as well as the opportunities of new environments (e.g. the home). Practical considerations need to be accounted for when planning capture in a particular environment so that data is analysable, whether it be finding a chair substitute, ways to support a patient or ensuring everyone does the exercise in the same manner. The home is a place of opportunity with vision-based body tracking, but it would be naïve to think that we can do what we do now in the clinic (e.g. balance tests) or in the home (e.g. play games), without appropriate modifications to what constitutes a practically capturable, clinically relevant measure.

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Research paper thumbnail of Lags in measuring eye–hand coordination

Journal of Neuroscience Methods, 2014

We challenge a number of the claims for novelty and innovation made in a recent published paper (... more We challenge a number of the claims for novelty and innovation made in a recent published paper (Lee et al., 2014) with regard to a computerised methodology that these authors present for assessing eye-hand coordination (EHC). Published work on similar pre-existing computerised systems is discussed and arguments made for these alternative systems being equal, if not superior, in terms of their innovativeness. The commentary does not dispute the usefulness of systems such as the one described by Lee et al. Rather, in the interests of scholarship it provides an accompanying insight into the significant scholarly contributions previously, and contemporaneously, being made by other research groups working in this area.

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Research paper thumbnail of Dual robot system for upper limb rehabilitation after stroke: the design process

Proceedings of The Institution of Mechanical Engineers Part C-journal of Mechanical Engineering Science, 2007

Stroke is the most common cause of severe disability in the UK. Arm impairment is common and reco... more Stroke is the most common cause of severe disability in the UK. Arm impairment is common and recovery is partly dependent on the intensity and frequency of rehabilitation inter- vention. However, physical therapy resources are often limited, so methods of supplementing traditional physiotherapy are essential. Robot assisted physiotherapy is one way to increase the duration patients spend participating in rehabilitation

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Research paper thumbnail of Development of a dual robotic system for upper-limb stroke rehabilitation

Stroke is a common condition resulting in 30,000 people per annum left with significant disabilit... more Stroke is a common condition resulting in 30,000 people per annum left with significant disability. In patients with severe arm paresis after stroke, functional recovery in the affected arm is poor. Inadequate intensity of treatment is cited as one factor accounting for the lack arm recovery found in some studies. Given that physical therapy resource is limited, strategies to enhance the physiotherapists' efforts are needed. One approach is to use robotic techniques to augment movement therapy. Kinematic analysis of upper limb movement during a patient's physiotherapy session was used to determine the appropriate therapeutic workspace. An existing single robot arm is adapted to optimize its operating area to allow full movement in this desired workspace. The kinematic data is also used to look at the constraints involved in attaching two robot arms to the user's forearm and upper arm. An optimized design and configuration of the dual robot arms is proposed that allows...

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Research paper thumbnail of Reviewing the technological challenges associated with the development of a laparoscopic palpation device

The International Journal of Medical Robotics and Computer Assisted Surgery, Jun 1, 2012

Minimally invasive surgery (MIS) has heralded a revolution in surgical practice, with numerous ad... more Minimally invasive surgery (MIS) has heralded a revolution in surgical practice, with numerous advantages over open surgery. Nevertheless, it prevents the surgeon from directly touching and manipulating tissue and therefore severely restricts the use of valuable techniques such as palpation. Accordingly a key challenge in MIS is to restore haptic feedback to the surgeon. This paper reviews the state-of-the-art in laparoscopic palpation devices (LPDs) with particular focus on device mechanisms, sensors and data analysis. It ...

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Research paper thumbnail of The coordination of upper and lower arm rotation

Experimental Brain Research, Feb 1, 2009

We tested the hypothesis that the upper and lower arm act as a coordinative structure coupled thr... more We tested the hypothesis that the upper and lower arm act as a coordinative structure coupled through a higher order control system. Five healthy participants moved their hand between two targets in ten conditions via internal/external rotation of the shoulder. In eight conditions, the task required concurrent rotation of the lower arm (180° pronation/supination). Movements were stereotypical within a condition but plotting the upper and lower arm angle against each other produced an asymmetrical pattern. With ...

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Research paper thumbnail of A new tool for assessing human movement: The Kinematic Assessment Tool

Journal of neuroscience methods, Oct 30, 2009

The study of human behaviour ultimately requires the documentation of human movement. In some ins... more The study of human behaviour ultimately requires the documentation of human movement. In some instances movements can be recorded through a simple button press on a computer input device. In other situations responses can be captured through questionnaire surveys. Nevertheless, there is a need within many neuroscience settings to capture how complex movements unfold over time (human kinematics). Current methods of measuring human kinematics range from accurate but multifarious laboratory configurations to ...

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Research paper thumbnail of The ontogeny of visual–motor memory and its importance in handwriting and reading: a developing construct

Humans have evolved a remarkable ability to remember visual shapes and use these representations ... more Humans have evolved a remarkable ability to remember visual shapes and use these representations to generate motor activity (from Palaeolithic cave drawings through Jiahu symbols to cursive handwriting). The term visual–motor memory (VMM) describes this psychological ability, which must have conveyed an evolutionary advantage and remains critically important to humans (e.g. when learning to write). Surprisingly, little empirical investigation of this unique human ability exists—almost certainly because of the technological difficulties involved in measuring VMM. We deployed a novel technique for measuring this construct in 87 children (6–11 years old, 44
females). Children drew novel shapes presented briefly on a tablet laptop screen, drawing their responses from memory on the screen using a digitizer stylus. Sophisticated algorithms (using point-registration techniques) objectively quantified the accuracy of the children’s reproductions. VMM improved with age and performance decreased with shape complexity, indicating that the measure captured meaningful developmental changes. The relationship between VMM and scores on nationally standardized writing assessments were explored with the results showing a clear relationship between these measures, even after controlling for age. Moreover, a relationship between VMM and the nationally standardized reading test was mediated via writing ability, suggesting VMM’s wider importance within language development.

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Research paper thumbnail of Friction characteristics of trocars in laparoscopic surgery

Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine, Jan 30, 2015

This article investigates the friction characteristics of the instrument-trocar interface in lapa... more This article investigates the friction characteristics of the instrument-trocar interface in laparoscopic surgery for varying linear instrument velocities, trocar seal design and material, and trocar tilt. Furthermore, the effect of applying lubrication at the instrument-trocar seal interface on friction was studied. A friction testing apparatus was designed and built to characterise the resistance force at the instrument-trocar interface as a function of the instrument's linear movement in the 12-mm trocar (at constant velocity) for different design, seal material, and angle of tilt. The resistance force depended on the trocar seal design and material properties, specifically surface roughness, elasticity, hardness, the direction of movement, and the instrument linear velocity, and varied between 0.25 and 8 N. Lubricating the shaft with silicone oil reduced the peak resistance force by 75% for all trocars and eliminated the stick-slip phenomenon evident in non-lubricated cases....

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Research paper thumbnail of Neurosurgical patties: adhesion and damage mitigation

Journal of Neurosurgery, 2015

OBJECT Neurosurgical patties are textile pads used during most neurosurgical operations to protec... more OBJECT Neurosurgical patties are textile pads used during most neurosurgical operations to protect tissues, manage the fluid environment, control hemostasis, and aid tissue manipulation. Recent research has suggested that, contrary to their aim, patties adhere to brain tissue and cause damage during removal. This study aimed to characterize and quantify the degree of and consequences resulting from adhesion between neurosurgical patties and brain tissue. METHODS Using a customized peel apparatus, the authors performed 90° peel tests on 5 patty products: Policot, Telfa, Americot, Delicot, and Ray-Cot (n = 247) from American Surgical Company. They tested 4 conditions: wet patty on glass (control), wet patty on wet brain peeled at 5 mm/sec (wet), dry patty on wet brain peeled at 5 mm/sec (dry), and wet patty on wet brain peeled at 20 mm/sec (speed). The interaction between patty and tissue was analyzed using peel-force traces and pre-peel histological analysis. RESULTS Adhesion strength differed between patty products (p < 0.001) and conditions (p < 0.001). Adhesion strength was greatest for Delicot patties under wet (2.22 mN/mm) and dry (9.88 mN/mm) conditions. For all patties, damage at the patty-tissue interface was proportional to the degree of fiber contact. When patties were irrigated, mechanical adhesion was reduced by up to 550% compared with dry usage. CONCLUSIONS For all patty products, mechanical (destructive) and liquid-mediated (nondestructive) adhesion caused damage to neural tissue. The greatest adhesion occurred with Delicot patties. To mitigate patty adhesion and neural tissue damage, surgeons should consider regular irrigation to be essential during neurosurgical procedures.

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Research paper thumbnail of The Cerebral Palsy Kinematic Assessment Tool (CPKAT): feasibility testing of a new portable tool for the objective evaluation of upper limb kinematics in children with cerebral palsy in the non-laboratory setting

Disability and Rehabilitation: Assistive Technology, 2014

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Vision-based body tracking: turning Kinect into a clinical tool

Disability and Rehabilitation: Assistive Technology, 2014

Abstract Purpose: Vision-based body tracking technologies, originally developed for the consumer ... more Abstract Purpose: Vision-based body tracking technologies, originally developed for the consumer gaming market, are being repurposed to form the core of a range of innovative healthcare applications in the clinical assessment and rehabilitation of movement ability. Vision-based body tracking has substantial potential, but there are technical limitations. Method: We use our "stories from the field" to articulate the challenges and offer examples of how these can be overcome. Results: We illustrate that: (i) substantial effort is needed to determine the measures and feedback vision-based body tracking should provide, accounting for the practicalities of the technology (e.g. range) as well as new environments (e.g. home). (ii) Practical considerations are important when planning data capture so that data is analysable, whether finding ways to support a patient or ensuring everyone does the exercise in the same manner. (iii) Home is a place of opportunity for vision-based body tracking, but what we do now in the clinic (e.g. balance tests) or in the home (e.g. play games) will require modifications to achieve capturable, clinically relevant measures. Conclusions: This article articulates how vision-based body tracking works and when it does not to continue to inspire our clinical colleagues to imagine new applications. Implications for Rehabilitation Vision-based body tracking has quickly been repurposed to form the core of innovative healthcare applications in clinical assessment and rehabilitation, but there are clinical as well as practical challenges to make such systems a reality. Substantial effort needs to go into determining what types of measures and feedback vision-based body tracking should provide. This needs to account for the practicalities of the technology (e.g. range) as well as the opportunities of new environments (e.g. the home). Practical considerations need to be accounted for when planning capture in a particular environment so that data is analysable, whether it be finding a chair substitute, ways to support a patient or ensuring everyone does the exercise in the same manner. The home is a place of opportunity with vision-based body tracking, but it would be naïve to think that we can do what we do now in the clinic (e.g. balance tests) or in the home (e.g. play games), without appropriate modifications to what constitutes a practically capturable, clinically relevant measure.

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Research paper thumbnail of Lags in measuring eye–hand coordination

Journal of Neuroscience Methods, 2014

We challenge a number of the claims for novelty and innovation made in a recent published paper (... more We challenge a number of the claims for novelty and innovation made in a recent published paper (Lee et al., 2014) with regard to a computerised methodology that these authors present for assessing eye-hand coordination (EHC). Published work on similar pre-existing computerised systems is discussed and arguments made for these alternative systems being equal, if not superior, in terms of their innovativeness. The commentary does not dispute the usefulness of systems such as the one described by Lee et al. Rather, in the interests of scholarship it provides an accompanying insight into the significant scholarly contributions previously, and contemporaneously, being made by other research groups working in this area.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Dual robot system for upper limb rehabilitation after stroke: the design process

Proceedings of The Institution of Mechanical Engineers Part C-journal of Mechanical Engineering Science, 2007

Stroke is the most common cause of severe disability in the UK. Arm impairment is common and reco... more Stroke is the most common cause of severe disability in the UK. Arm impairment is common and recovery is partly dependent on the intensity and frequency of rehabilitation inter- vention. However, physical therapy resources are often limited, so methods of supplementing traditional physiotherapy are essential. Robot assisted physiotherapy is one way to increase the duration patients spend participating in rehabilitation

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Development of a dual robotic system for upper-limb stroke rehabilitation

Stroke is a common condition resulting in 30,000 people per annum left with significant disabilit... more Stroke is a common condition resulting in 30,000 people per annum left with significant disability. In patients with severe arm paresis after stroke, functional recovery in the affected arm is poor. Inadequate intensity of treatment is cited as one factor accounting for the lack arm recovery found in some studies. Given that physical therapy resource is limited, strategies to enhance the physiotherapists' efforts are needed. One approach is to use robotic techniques to augment movement therapy. Kinematic analysis of upper limb movement during a patient's physiotherapy session was used to determine the appropriate therapeutic workspace. An existing single robot arm is adapted to optimize its operating area to allow full movement in this desired workspace. The kinematic data is also used to look at the constraints involved in attaching two robot arms to the user's forearm and upper arm. An optimized design and configuration of the dual robot arms is proposed that allows...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Reviewing the technological challenges associated with the development of a laparoscopic palpation device

The International Journal of Medical Robotics and Computer Assisted Surgery, Jun 1, 2012

Minimally invasive surgery (MIS) has heralded a revolution in surgical practice, with numerous ad... more Minimally invasive surgery (MIS) has heralded a revolution in surgical practice, with numerous advantages over open surgery. Nevertheless, it prevents the surgeon from directly touching and manipulating tissue and therefore severely restricts the use of valuable techniques such as palpation. Accordingly a key challenge in MIS is to restore haptic feedback to the surgeon. This paper reviews the state-of-the-art in laparoscopic palpation devices (LPDs) with particular focus on device mechanisms, sensors and data analysis. It ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The coordination of upper and lower arm rotation

Experimental Brain Research, Feb 1, 2009

We tested the hypothesis that the upper and lower arm act as a coordinative structure coupled thr... more We tested the hypothesis that the upper and lower arm act as a coordinative structure coupled through a higher order control system. Five healthy participants moved their hand between two targets in ten conditions via internal/external rotation of the shoulder. In eight conditions, the task required concurrent rotation of the lower arm (180° pronation/supination). Movements were stereotypical within a condition but plotting the upper and lower arm angle against each other produced an asymmetrical pattern. With ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A new tool for assessing human movement: The Kinematic Assessment Tool

Journal of neuroscience methods, Oct 30, 2009

The study of human behaviour ultimately requires the documentation of human movement. In some ins... more The study of human behaviour ultimately requires the documentation of human movement. In some instances movements can be recorded through a simple button press on a computer input device. In other situations responses can be captured through questionnaire surveys. Nevertheless, there is a need within many neuroscience settings to capture how complex movements unfold over time (human kinematics). Current methods of measuring human kinematics range from accurate but multifarious laboratory configurations to ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The ontogeny of visual–motor memory and its importance in handwriting and reading: a developing construct

Humans have evolved a remarkable ability to remember visual shapes and use these representations ... more Humans have evolved a remarkable ability to remember visual shapes and use these representations to generate motor activity (from Palaeolithic cave drawings through Jiahu symbols to cursive handwriting). The term visual–motor memory (VMM) describes this psychological ability, which must have conveyed an evolutionary advantage and remains critically important to humans (e.g. when learning to write). Surprisingly, little empirical investigation of this unique human ability exists—almost certainly because of the technological difficulties involved in measuring VMM. We deployed a novel technique for measuring this construct in 87 children (6–11 years old, 44
females). Children drew novel shapes presented briefly on a tablet laptop screen, drawing their responses from memory on the screen using a digitizer stylus. Sophisticated algorithms (using point-registration techniques) objectively quantified the accuracy of the children’s reproductions. VMM improved with age and performance decreased with shape complexity, indicating that the measure captured meaningful developmental changes. The relationship between VMM and scores on nationally standardized writing assessments were explored with the results showing a clear relationship between these measures, even after controlling for age. Moreover, a relationship between VMM and the nationally standardized reading test was mediated via writing ability, suggesting VMM’s wider importance within language development.

Bookmarks Related papers MentionsView impact