As the Web becomes more integral to day-to-day life, there is a danger that many older people wil... more As the Web becomes more integral to day-to-day life, there is a danger that many older people will be excluded if their access needs are not considered by content designers. Although accessibility guidelines for designers are available, experience shows that these guidelines have not been successful enough in producing Web sites accessible to older people. In this paper, the shortcomings of relying solely on accessibility guidelines are reviewed, and several ideas are proposed for encouraging a more holistic approach to accessibility.
A course on computers was run for computer beginners aged over 55. An iterative and flexible appr... more A course on computers was run for computer beginners aged over 55. An iterative and flexible approach aimed to ensure that students’ anxieties and difficulties were addressed as the course proceeded. Several layers of difficulty were encountered, ranging from initial difficulties understanding Windows systems and the working of the mouse to more fundamental and long-term problems such as repeatedly forgetting
Magnetic resonance imaging (MRI)-guided deep brain stimulation (DBS) and high frequency focused u... more Magnetic resonance imaging (MRI)-guided deep brain stimulation (DBS) and high frequency focused ultrasound (FUS) is an emerging modality to treat several neurological disorders of the brain. Developing reliable models to train and assess future neurosurgeons is paramount to ensure safety and adequate training of neurosurgeons of the future. We evaluated the use of Thiel cadaveric model to practice MRI-guided DBS implantation and high frequency MRI-guided FUS in the human brain. We performed three training sessions for DBS and five sonications using high frequency MRI-guided FUS in five consecutive cadavers to assess the suitability of this model to use in training for stereotactic functional procedures. We found the brains of these cadavers preserved in an excellent anatomical condition up to 15 months after embalmment and they were excellent model to use, MRI-guided DBS implantation and FUS produced the desired lesions accurately and precisely in these cadaveric brains. Thiel cadav...
The use of endourology training models is on the rise. Surgical practice is moving toward a more ... more The use of endourology training models is on the rise. Surgical practice is moving toward a more minimally invasive approach and deficits in surgical exposure by enforcement of the European Working Time Directive call for simulation models to be anatomically sound. Thiel-embalmed cadavers have been found to demonstrate efficacy in tissue quality, elasticity, and handling in addition to playing a role in teaching and training. This review summarizes the current status of the Thiel method and its role in urologic skills training.
Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exp... more Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exposure to clinical cases. As such, there is widespread acceptance that trainees need to train in environments other than the ward or operating theatre in order to gain practical skills. Formalin-fixed cadavers demonstrate gross muscle and nerve anatomy but needle insertion under ultrasound guidance is poor. In contrast, a new development in medical simulation is the use of Thiel-embalmed cadavers, developed by Professor Thiel of the University of Graz, Austria, using a novel preservation technique that retains full flexibility of the limbs. Thiel cadavers have been used to successfully simulate laparoscopic surgery, neurosurgery and oral surgery. This paper investigates, for the first time, the application of ultrasound-based regional anaesthesia to the Thiel cadaver by tracing the course of peripheral nerves, injecting local anaesthetic around nerves, and reproducing inadvertent intraneural injection by injecting preservative directly into the nerve. The Thiel cadaver provides good conditions for anaesthetists to simulate regional anaesthetic block techniques using ultrasound.
Ultrasound guidance is now the standard procedure for regional nerve block in anaesthesiology. Ho... more Ultrasound guidance is now the standard procedure for regional nerve block in anaesthesiology. However, ultrasonic visualisation of needle manipulation and guidance within tissues n remains a problem. Two new echogenic needles (Pajunk and Braun) have been introduced to anaesthesiology clinical practice, but evaluation has been restricted to preserved animal tissue. In this study the visibility of both echogenic needles was compared to a standard non echogenic needle in a Thiel cadaver model. A total of 144 intramuscular injections were made in the upper arm in-plane and out-of-plane to the ultrasound beam at 4 angles (30o, 45o, 60o and 75o). The visibility of the needle was assessed by two independent, blinded observers using a 5-point Likert ordinal scale. Weighted Kappa for interobserver agreement was 0.77 (95% CI: 0.68 -0.86). The Pajunk Echogenic needle was more visible than the Braun Standard needle in-plane (P=0.04), and the Braun Standard and Braun Echogenic needles out of plane (P=0.02). Independent predictors of visibility using logistic regression were needle (p<0.001) and plane of insertion (p=0.08), Receiver Operator Characteristic (ROC) area under the curve 0.90. In conclusion, the Pajunk echogenic needle offers the best visibility for ultrasound guided regional anaesthesia.
Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor v... more Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor visibility of the needle tip and poor quantification of local anaesthetic spread. Sonoelastography based on tissue compression is a technique depicting tissue strain. Hitherto used largely for tumour diagnosis, we used it in both Thiel embalmed cadavers and two patients receiving interscalene and femoral blocks to observe changes in tissue strain during local anaesthetic injection. The primary aim of our study was to measure the area under the curve (weighted for time) of the strain pattern in Thiel perineural tissue when using a range of volumes of embalming fluid (0.25, 0.5, 1, 2.5, 5 and 7.5 ml) for interscalene and femoral blocks using sonoelastography. Our secondary aims were to evaluate static images of anatomy and videos of needle insertion and perineural injection using combined B-Mode ultrasound and sonoelastography. Independent raters assessed the anatomy and spread using a 7-point Likert scale, ranked from extremely poor to extremely good. We performed 83 blocks in cadavers. Concordance between both raters was good, with weighted Kappa (95% CI) 0.66 (0.61-0.71). The characteristics of spread were similar with both interscalene and femoral block; spread increased with injectate volume up to 1 ml. Analysis of variance showed differences in spread between injection volumes (p = 0.009), but not between regional blocks (p = 0.05). Post-hoc analysis showed greater spread with 1 and 2.5 ml volumes compared with 0.25 ml. In patients, visibility of strain during injection was better with sonoelastography than with B-Mode ultrasound and showed a dose response from 1 to 5 ml volumes of local anaesthetic. Colour strain recognition using sonoelastography offers the ability to differentiate between nerve and surrounding tissue during local anaesthetic injection by improving visibility of spread (p = 0.04).
For decades, embalmed cadavers have played an important role in teaching anatomy to the scientist... more For decades, embalmed cadavers have played an important role in teaching anatomy to the scientists and doctors of the future. Most anatomy departments use a traditional formaldehyde-based embalming method, but formalin embalming makes the bodies very rigid, which limits their usefulness for procedures other than dissection. A more recent embalming method developed by W. Thiel has allowed these &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;silent teachers&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; to take on a further role in applied anatomy research and teaching: to act as models for surgical training and medical research.
The European Working Time Directive has increased the need for surgical skills training which doe... more The European Working Time Directive has increased the need for surgical skills training which does not involve patients. Recent changes in the anatomy legislation now make it possible to perform surgical procedures on human cadavers. Standard formalin embalming, however does not provide a very realistic model and alternative approaches, such as Thiel soft-fix embalmed cadavers, should be explored and evaluated. Two formalin and 3 Thiel embalmed cadavers were used at a senior trainee and consultant course in thyroid surgery. The 12 participants (8 trainees and 4 consultants) were asked to score 15 aspects, such as quality of different tissues, for each type of cadaver. Some of these aspects were specific to thyroid surgery, however many are equally applicable to other specialties. All participants rated the Thiel embalmed cadavers better or equal for all aspects. Of the 180 pairs of scores 33 were excluded, 10 were equal for formalin and Thiel, while in the remaining 137 Thiel scored better. The preference was particularly pronounced in aspects that require flexibility of tissues such as flap raising. Thiel embalmed cadavers provide a more realistic model for training of thyroid surgical skills; this is expected to be similar for many other types of surgery.
Respiration-related movement of organs is a complication in a range of diagnostic and interventio... more Respiration-related movement of organs is a complication in a range of diagnostic and interventional procedures. The development and validation of techniques to compensate for such movement requires appropriate models. Human cadavers embalmed with the Thiel method remain flexible and could provide a suitable model. In this study liver displacement during ventilation was assessed in eight Thiel embalmed cadavers, all of which showed thoracic and abdominal motion. Four cadavers displayed realistic lung behaviour, one showed some signs of pneumothorax after prolonged ventilation, one had limited filling of the lungs, and two displayed significant leakage of air into the thorax. A coronal slice containing the largest section through the liver was imaged with a real-time Fast Gradient Echo (FGR) MRI sequence: Craniocaudal displacement of the liver was then determined from a time-series of slices. The maximum liver displacement observed in the cadavers ranged from 7 to 35 mm. The ventilation applied was comparable to tidal breathing at rest and the results found for liver displacement are similar to values in the literature for respiratory motion of the liver under similar conditions. This indicates that Thiel embalmed cadavers have potential as a model for research and training in minimally invasive procedures.
To explain the observed considerable loss of signal and contrast when Thiel-embalmed human cadave... more To explain the observed considerable loss of signal and contrast when Thiel-embalmed human cadavers are imaged using clinical magnetic resonance imaging (MRI) sequences, especially those based on spin-echo MRI. All cadavers were imaged with a medical 1.5T scanner using standard MRI sequences. Dual angle B1+ magnitude mapping and electromagnetic (EM) simulations that characterize the radiofrequency (RF) penetration in a male human body model (HBM) were carried out for a range of tissue conductivities. The EM simulations show that RF penetration issues begin to affect the image quality for values of electrical conductivity as low as 2.6 S/m. The electrical conductivity values of the embalming fluids were found to be within the range of 5-10.6 S/m, thus strongly suggesting that the observed loss in signal and contrast is due to diminished RF penetration inside the cadavers. Furthermore, it was demonstrated that gradient-echo (GRE)-based MRI sequences perform better than spin-echo (SE)-based sequences, as they are less susceptible to imperfections in the flip angle that are inevitably present when imaging Thiel cadavers. The diminished signal and contrast observed when imaging Thiel-embalmed human cadavers may be attributed to the high conductivity of the embalming liquids.
Anthropological examination of defleshed bones is the gold standard for osteological measurement ... more Anthropological examination of defleshed bones is the gold standard for osteological measurement in forensic practice. However, multi-detector computed tomography (MDCT) offers the opportunity of three-dimensional imaging of skeletal elements, allowing measurement of bones in any plane without defleshing. We present our experiences of the examination of 15 human lower limbs in different states of decomposition using MDCT. We present our method of imaging and radiological measurement of the bones including sex assessment. The radiological measurements were undertaken by three professional groups-anthropology, radiology, and forensic pathology-both at the site of scanning and at a remote site. The results were compared to anthropological oestological assessment of the defleshed bones. We discuss the limitations of this technique and the potential applications of our observations. We introduce the concept of remote radiological anthropological measurement of bones, so-called teleanthro-radiology and the role that this could play in providing the facility for standardization of protocols, international peer review and quality assurance schemes.
As the Web becomes more integral to day-to-day life, there is a danger that many older people wil... more As the Web becomes more integral to day-to-day life, there is a danger that many older people will be excluded if their access needs are not considered by content designers. Although accessibility guidelines for designers are available, experience shows that these guidelines have not been successful enough in producing Web sites accessible to older people. In this paper, the shortcomings of relying solely on accessibility guidelines are reviewed, and several ideas are proposed for encouraging a more holistic approach to accessibility.
In 2009, the Centre for Anatomy and Human Identification started Thiel embalming on a small scale... more In 2009, the Centre for Anatomy and Human Identification started Thiel embalming on a small scale to assess (i) the suitability for our current teaching in which long-lasting dissection courses are key, (ii) the potential for new collaborations and activities, and (iii) the practical implications of changing our embalming method from formalin to Thiel. Twenty six Thiel-embalmed cadavers have been used for dissection by staff and students on a taught MSc course, as a model for clinical and surgical training, and increasingly as a model for evaluation of new medical devices and procedures. Our experiences with dissection were mostly positive especially for teaching the musculoskeletal system. Internal organs handle differently from formalin-fixed organs and dissection manuals need to be adjusted to reflect this. Durability of the cadavers was not an issue, though changes are seen over time due to gradual fluid loss. We have started new collaborations related to postgraduate anatomy teaching and advanced training in surgical and clinical skills. In general, feedback is very positive and demand for cadavers outstrips our current limited supply. Thiel-embalmed cadavers were found to provide a unique opportunity for evaluation of medical products especially in areas where no suitable alternative model is available, and without the complications associated with clinical testing. This has resulted in new collaborations and research projects. As a result Thiel-embalmed cadavers are used for longer and for more activities than formalin cadavers: this requires changes in our procedures and staff roles.
Human cadaveric tissue is the fundamental substrate for basic anatomic and surgical skills traini... more Human cadaveric tissue is the fundamental substrate for basic anatomic and surgical skills training. A qualitative assessment of the use of human cadavers preserved by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method for a British Association of Urological Surgeons-approved, advanced laparoscopic renal resection skills training course is described in the present study. Four trainees and four experienced laparoscopic surgeons participated in the course. All participants completed a five-point Likert scale satisfaction questionnaire after their training sessions. The quality of cadaveric tissue and the training session were assessed with particular emphasis placed on the ease of patient positioning, the ease of trocar placement, the preservation of tissue planes, the ease of renal pedicle dissection, and the quality of tissue preservation. All of the participants highly rated the quality of the cadaveric tissue embalmed by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method (mean scores for quality on the five-point Likert scale were 4.5 and 4.3 by the trainees and experienced laparoscopic surgeons, respectively). All of the steps of laparoscopic renal resection were rated 4.0 or more on the Likert scale by both trainees and faculty members. The initial response rates for using a human cadaver embalmed by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method as a training tool for laparoscopic nephrectomy showed encouraging results. The performance of a laparoscopic nephrectomy on a human cadaver embalmed by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method bears close resemblance to real laparoscopic nephrectomy procedures, and thus demonstrates added advantages to the previously reported models.
Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor v... more Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor visibility of the needle tip and poor quantification of local anaesthetic spread. Sonoelastography based on tissue compression is a technique depicting tissue strain. Hitherto used largely for tumour diagnosis, we used it in both Thiel embalmed cadavers and two patients receiving interscalene and femoral blocks to observe changes in tissue strain during local anaesthetic injection. The primary aim of our study was to measure the area under the curve (weighted for time) of the strain pattern in Thiel perineural tissue when using a range of volumes of embalming fluid (0.25, 0.5, 1, 2.5, 5 and 7.5 ml) for interscalene and femoral blocks using sonoelastography. Our secondary aims were to evaluate static images of anatomy and videos of needle insertion and perineural injection using combined B-Mode ultrasound and sonoelastography. Independent raters assessed the anatomy and spread using a 7-point Likert scale, ranked from extremely poor to extremely good. We performed 83 blocks in cadavers. Concordance between both raters was good, with weighted Kappa (95% CI) 0.66 (0.61-0.71). The characteristics of spread were similar with both interscalene and femoral block; spread increased with injectate volume up to 1 ml. Analysis of variance showed differences in spread between injection volumes (p = 0.009), but not between regional blocks (p = 0.05). Post-hoc analysis showed greater spread with 1 and 2.5 ml volumes compared with 0.25 ml. In patients, visibility of strain during injection was better with sonoelastography than with B-Mode ultrasound and showed a dose response from 1 to 5 ml volumes of local anaesthetic. Colour strain recognition using sonoelastography offers the ability to differentiate between nerve and surrounding tissue during local anaesthetic injection by improving visibility of spread (p = 0.04).
Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exp... more Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exposure to clinical cases. As such, there is widespread acceptance that trainees need to train in environments other than the ward or operating theatre in order to gain practical skills. Formalin-fixed cadavers demonstrate gross muscle and nerve anatomy but needle insertion under ultrasound guidance is poor. In contrast, a new development in medical simulation is the use of Thiel-embalmed cadavers, developed by Professor Thiel of the University of Graz, Austria, using a novel preservation technique that retains full flexibility of the limbs. Thiel cadavers have been used to successfully simulate laparoscopic surgery, neurosurgery and oral surgery. This paper investigates, for the first time, the application of ultrasound-based regional anaesthesia to the Thiel cadaver by tracing the course of peripheral nerves, injecting local anaesthetic around nerves, and reproducing inadvertent intraneural injection by injecting preservative directly into the nerve. The Thiel cadaver provides good conditions for anaesthetists to simulate regional anaesthetic block techniques using ultrasound.
As the Web becomes more integral to day-to-day life, there is a danger that many older people wil... more As the Web becomes more integral to day-to-day life, there is a danger that many older people will be excluded if their access needs are not considered by content designers. Although accessibility guidelines for designers are available, experience shows that these guidelines have not been successful enough in producing Web sites accessible to older people. In this paper, the shortcomings of relying solely on accessibility guidelines are reviewed, and several ideas are proposed for encouraging a more holistic approach to accessibility.
A course on computers was run for computer beginners aged over 55. An iterative and flexible appr... more A course on computers was run for computer beginners aged over 55. An iterative and flexible approach aimed to ensure that students’ anxieties and difficulties were addressed as the course proceeded. Several layers of difficulty were encountered, ranging from initial difficulties understanding Windows systems and the working of the mouse to more fundamental and long-term problems such as repeatedly forgetting
Magnetic resonance imaging (MRI)-guided deep brain stimulation (DBS) and high frequency focused u... more Magnetic resonance imaging (MRI)-guided deep brain stimulation (DBS) and high frequency focused ultrasound (FUS) is an emerging modality to treat several neurological disorders of the brain. Developing reliable models to train and assess future neurosurgeons is paramount to ensure safety and adequate training of neurosurgeons of the future. We evaluated the use of Thiel cadaveric model to practice MRI-guided DBS implantation and high frequency MRI-guided FUS in the human brain. We performed three training sessions for DBS and five sonications using high frequency MRI-guided FUS in five consecutive cadavers to assess the suitability of this model to use in training for stereotactic functional procedures. We found the brains of these cadavers preserved in an excellent anatomical condition up to 15 months after embalmment and they were excellent model to use, MRI-guided DBS implantation and FUS produced the desired lesions accurately and precisely in these cadaveric brains. Thiel cadav...
The use of endourology training models is on the rise. Surgical practice is moving toward a more ... more The use of endourology training models is on the rise. Surgical practice is moving toward a more minimally invasive approach and deficits in surgical exposure by enforcement of the European Working Time Directive call for simulation models to be anatomically sound. Thiel-embalmed cadavers have been found to demonstrate efficacy in tissue quality, elasticity, and handling in addition to playing a role in teaching and training. This review summarizes the current status of the Thiel method and its role in urologic skills training.
Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exp... more Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exposure to clinical cases. As such, there is widespread acceptance that trainees need to train in environments other than the ward or operating theatre in order to gain practical skills. Formalin-fixed cadavers demonstrate gross muscle and nerve anatomy but needle insertion under ultrasound guidance is poor. In contrast, a new development in medical simulation is the use of Thiel-embalmed cadavers, developed by Professor Thiel of the University of Graz, Austria, using a novel preservation technique that retains full flexibility of the limbs. Thiel cadavers have been used to successfully simulate laparoscopic surgery, neurosurgery and oral surgery. This paper investigates, for the first time, the application of ultrasound-based regional anaesthesia to the Thiel cadaver by tracing the course of peripheral nerves, injecting local anaesthetic around nerves, and reproducing inadvertent intraneural injection by injecting preservative directly into the nerve. The Thiel cadaver provides good conditions for anaesthetists to simulate regional anaesthetic block techniques using ultrasound.
Ultrasound guidance is now the standard procedure for regional nerve block in anaesthesiology. Ho... more Ultrasound guidance is now the standard procedure for regional nerve block in anaesthesiology. However, ultrasonic visualisation of needle manipulation and guidance within tissues n remains a problem. Two new echogenic needles (Pajunk and Braun) have been introduced to anaesthesiology clinical practice, but evaluation has been restricted to preserved animal tissue. In this study the visibility of both echogenic needles was compared to a standard non echogenic needle in a Thiel cadaver model. A total of 144 intramuscular injections were made in the upper arm in-plane and out-of-plane to the ultrasound beam at 4 angles (30o, 45o, 60o and 75o). The visibility of the needle was assessed by two independent, blinded observers using a 5-point Likert ordinal scale. Weighted Kappa for interobserver agreement was 0.77 (95% CI: 0.68 -0.86). The Pajunk Echogenic needle was more visible than the Braun Standard needle in-plane (P=0.04), and the Braun Standard and Braun Echogenic needles out of plane (P=0.02). Independent predictors of visibility using logistic regression were needle (p<0.001) and plane of insertion (p=0.08), Receiver Operator Characteristic (ROC) area under the curve 0.90. In conclusion, the Pajunk echogenic needle offers the best visibility for ultrasound guided regional anaesthesia.
Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor v... more Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor visibility of the needle tip and poor quantification of local anaesthetic spread. Sonoelastography based on tissue compression is a technique depicting tissue strain. Hitherto used largely for tumour diagnosis, we used it in both Thiel embalmed cadavers and two patients receiving interscalene and femoral blocks to observe changes in tissue strain during local anaesthetic injection. The primary aim of our study was to measure the area under the curve (weighted for time) of the strain pattern in Thiel perineural tissue when using a range of volumes of embalming fluid (0.25, 0.5, 1, 2.5, 5 and 7.5 ml) for interscalene and femoral blocks using sonoelastography. Our secondary aims were to evaluate static images of anatomy and videos of needle insertion and perineural injection using combined B-Mode ultrasound and sonoelastography. Independent raters assessed the anatomy and spread using a 7-point Likert scale, ranked from extremely poor to extremely good. We performed 83 blocks in cadavers. Concordance between both raters was good, with weighted Kappa (95% CI) 0.66 (0.61-0.71). The characteristics of spread were similar with both interscalene and femoral block; spread increased with injectate volume up to 1 ml. Analysis of variance showed differences in spread between injection volumes (p = 0.009), but not between regional blocks (p = 0.05). Post-hoc analysis showed greater spread with 1 and 2.5 ml volumes compared with 0.25 ml. In patients, visibility of strain during injection was better with sonoelastography than with B-Mode ultrasound and showed a dose response from 1 to 5 ml volumes of local anaesthetic. Colour strain recognition using sonoelastography offers the ability to differentiate between nerve and surrounding tissue during local anaesthetic injection by improving visibility of spread (p = 0.04).
For decades, embalmed cadavers have played an important role in teaching anatomy to the scientist... more For decades, embalmed cadavers have played an important role in teaching anatomy to the scientists and doctors of the future. Most anatomy departments use a traditional formaldehyde-based embalming method, but formalin embalming makes the bodies very rigid, which limits their usefulness for procedures other than dissection. A more recent embalming method developed by W. Thiel has allowed these &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;silent teachers&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; to take on a further role in applied anatomy research and teaching: to act as models for surgical training and medical research.
The European Working Time Directive has increased the need for surgical skills training which doe... more The European Working Time Directive has increased the need for surgical skills training which does not involve patients. Recent changes in the anatomy legislation now make it possible to perform surgical procedures on human cadavers. Standard formalin embalming, however does not provide a very realistic model and alternative approaches, such as Thiel soft-fix embalmed cadavers, should be explored and evaluated. Two formalin and 3 Thiel embalmed cadavers were used at a senior trainee and consultant course in thyroid surgery. The 12 participants (8 trainees and 4 consultants) were asked to score 15 aspects, such as quality of different tissues, for each type of cadaver. Some of these aspects were specific to thyroid surgery, however many are equally applicable to other specialties. All participants rated the Thiel embalmed cadavers better or equal for all aspects. Of the 180 pairs of scores 33 were excluded, 10 were equal for formalin and Thiel, while in the remaining 137 Thiel scored better. The preference was particularly pronounced in aspects that require flexibility of tissues such as flap raising. Thiel embalmed cadavers provide a more realistic model for training of thyroid surgical skills; this is expected to be similar for many other types of surgery.
Respiration-related movement of organs is a complication in a range of diagnostic and interventio... more Respiration-related movement of organs is a complication in a range of diagnostic and interventional procedures. The development and validation of techniques to compensate for such movement requires appropriate models. Human cadavers embalmed with the Thiel method remain flexible and could provide a suitable model. In this study liver displacement during ventilation was assessed in eight Thiel embalmed cadavers, all of which showed thoracic and abdominal motion. Four cadavers displayed realistic lung behaviour, one showed some signs of pneumothorax after prolonged ventilation, one had limited filling of the lungs, and two displayed significant leakage of air into the thorax. A coronal slice containing the largest section through the liver was imaged with a real-time Fast Gradient Echo (FGR) MRI sequence: Craniocaudal displacement of the liver was then determined from a time-series of slices. The maximum liver displacement observed in the cadavers ranged from 7 to 35 mm. The ventilation applied was comparable to tidal breathing at rest and the results found for liver displacement are similar to values in the literature for respiratory motion of the liver under similar conditions. This indicates that Thiel embalmed cadavers have potential as a model for research and training in minimally invasive procedures.
To explain the observed considerable loss of signal and contrast when Thiel-embalmed human cadave... more To explain the observed considerable loss of signal and contrast when Thiel-embalmed human cadavers are imaged using clinical magnetic resonance imaging (MRI) sequences, especially those based on spin-echo MRI. All cadavers were imaged with a medical 1.5T scanner using standard MRI sequences. Dual angle B1+ magnitude mapping and electromagnetic (EM) simulations that characterize the radiofrequency (RF) penetration in a male human body model (HBM) were carried out for a range of tissue conductivities. The EM simulations show that RF penetration issues begin to affect the image quality for values of electrical conductivity as low as 2.6 S/m. The electrical conductivity values of the embalming fluids were found to be within the range of 5-10.6 S/m, thus strongly suggesting that the observed loss in signal and contrast is due to diminished RF penetration inside the cadavers. Furthermore, it was demonstrated that gradient-echo (GRE)-based MRI sequences perform better than spin-echo (SE)-based sequences, as they are less susceptible to imperfections in the flip angle that are inevitably present when imaging Thiel cadavers. The diminished signal and contrast observed when imaging Thiel-embalmed human cadavers may be attributed to the high conductivity of the embalming liquids.
Anthropological examination of defleshed bones is the gold standard for osteological measurement ... more Anthropological examination of defleshed bones is the gold standard for osteological measurement in forensic practice. However, multi-detector computed tomography (MDCT) offers the opportunity of three-dimensional imaging of skeletal elements, allowing measurement of bones in any plane without defleshing. We present our experiences of the examination of 15 human lower limbs in different states of decomposition using MDCT. We present our method of imaging and radiological measurement of the bones including sex assessment. The radiological measurements were undertaken by three professional groups-anthropology, radiology, and forensic pathology-both at the site of scanning and at a remote site. The results were compared to anthropological oestological assessment of the defleshed bones. We discuss the limitations of this technique and the potential applications of our observations. We introduce the concept of remote radiological anthropological measurement of bones, so-called teleanthro-radiology and the role that this could play in providing the facility for standardization of protocols, international peer review and quality assurance schemes.
As the Web becomes more integral to day-to-day life, there is a danger that many older people wil... more As the Web becomes more integral to day-to-day life, there is a danger that many older people will be excluded if their access needs are not considered by content designers. Although accessibility guidelines for designers are available, experience shows that these guidelines have not been successful enough in producing Web sites accessible to older people. In this paper, the shortcomings of relying solely on accessibility guidelines are reviewed, and several ideas are proposed for encouraging a more holistic approach to accessibility.
In 2009, the Centre for Anatomy and Human Identification started Thiel embalming on a small scale... more In 2009, the Centre for Anatomy and Human Identification started Thiel embalming on a small scale to assess (i) the suitability for our current teaching in which long-lasting dissection courses are key, (ii) the potential for new collaborations and activities, and (iii) the practical implications of changing our embalming method from formalin to Thiel. Twenty six Thiel-embalmed cadavers have been used for dissection by staff and students on a taught MSc course, as a model for clinical and surgical training, and increasingly as a model for evaluation of new medical devices and procedures. Our experiences with dissection were mostly positive especially for teaching the musculoskeletal system. Internal organs handle differently from formalin-fixed organs and dissection manuals need to be adjusted to reflect this. Durability of the cadavers was not an issue, though changes are seen over time due to gradual fluid loss. We have started new collaborations related to postgraduate anatomy teaching and advanced training in surgical and clinical skills. In general, feedback is very positive and demand for cadavers outstrips our current limited supply. Thiel-embalmed cadavers were found to provide a unique opportunity for evaluation of medical products especially in areas where no suitable alternative model is available, and without the complications associated with clinical testing. This has resulted in new collaborations and research projects. As a result Thiel-embalmed cadavers are used for longer and for more activities than formalin cadavers: this requires changes in our procedures and staff roles.
Human cadaveric tissue is the fundamental substrate for basic anatomic and surgical skills traini... more Human cadaveric tissue is the fundamental substrate for basic anatomic and surgical skills training. A qualitative assessment of the use of human cadavers preserved by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method for a British Association of Urological Surgeons-approved, advanced laparoscopic renal resection skills training course is described in the present study. Four trainees and four experienced laparoscopic surgeons participated in the course. All participants completed a five-point Likert scale satisfaction questionnaire after their training sessions. The quality of cadaveric tissue and the training session were assessed with particular emphasis placed on the ease of patient positioning, the ease of trocar placement, the preservation of tissue planes, the ease of renal pedicle dissection, and the quality of tissue preservation. All of the participants highly rated the quality of the cadaveric tissue embalmed by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method (mean scores for quality on the five-point Likert scale were 4.5 and 4.3 by the trainees and experienced laparoscopic surgeons, respectively). All of the steps of laparoscopic renal resection were rated 4.0 or more on the Likert scale by both trainees and faculty members. The initial response rates for using a human cadaver embalmed by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method as a training tool for laparoscopic nephrectomy showed encouraging results. The performance of a laparoscopic nephrectomy on a human cadaver embalmed by Thiel&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s method bears close resemblance to real laparoscopic nephrectomy procedures, and thus demonstrates added advantages to the previously reported models.
Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor v... more Ultrasound guidance is now common in regional anaesthesia practice, but remains limited by poor visibility of the needle tip and poor quantification of local anaesthetic spread. Sonoelastography based on tissue compression is a technique depicting tissue strain. Hitherto used largely for tumour diagnosis, we used it in both Thiel embalmed cadavers and two patients receiving interscalene and femoral blocks to observe changes in tissue strain during local anaesthetic injection. The primary aim of our study was to measure the area under the curve (weighted for time) of the strain pattern in Thiel perineural tissue when using a range of volumes of embalming fluid (0.25, 0.5, 1, 2.5, 5 and 7.5 ml) for interscalene and femoral blocks using sonoelastography. Our secondary aims were to evaluate static images of anatomy and videos of needle insertion and perineural injection using combined B-Mode ultrasound and sonoelastography. Independent raters assessed the anatomy and spread using a 7-point Likert scale, ranked from extremely poor to extremely good. We performed 83 blocks in cadavers. Concordance between both raters was good, with weighted Kappa (95% CI) 0.66 (0.61-0.71). The characteristics of spread were similar with both interscalene and femoral block; spread increased with injectate volume up to 1 ml. Analysis of variance showed differences in spread between injection volumes (p = 0.009), but not between regional blocks (p = 0.05). Post-hoc analysis showed greater spread with 1 and 2.5 ml volumes compared with 0.25 ml. In patients, visibility of strain during injection was better with sonoelastography than with B-Mode ultrasound and showed a dose response from 1 to 5 ml volumes of local anaesthetic. Colour strain recognition using sonoelastography offers the ability to differentiate between nerve and surrounding tissue during local anaesthetic injection by improving visibility of spread (p = 0.04).
Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exp... more Working hours of UK trainee doctors have recently been reduced to 48 hours per week, reducing exposure to clinical cases. As such, there is widespread acceptance that trainees need to train in environments other than the ward or operating theatre in order to gain practical skills. Formalin-fixed cadavers demonstrate gross muscle and nerve anatomy but needle insertion under ultrasound guidance is poor. In contrast, a new development in medical simulation is the use of Thiel-embalmed cadavers, developed by Professor Thiel of the University of Graz, Austria, using a novel preservation technique that retains full flexibility of the limbs. Thiel cadavers have been used to successfully simulate laparoscopic surgery, neurosurgery and oral surgery. This paper investigates, for the first time, the application of ultrasound-based regional anaesthesia to the Thiel cadaver by tracing the course of peripheral nerves, injecting local anaesthetic around nerves, and reproducing inadvertent intraneural injection by injecting preservative directly into the nerve. The Thiel cadaver provides good conditions for anaesthetists to simulate regional anaesthetic block techniques using ultrasound.
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