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Journal of Forensic Sciences Sep 2020Correctly assessing heart weight can be critical at postmortem examination. The current international guidelines advocate using the short-axis method in dissecting the...
Correctly assessing heart weight can be critical at postmortem examination. The current international guidelines advocate using the short-axis method in dissecting the heart and the heart weighed when the blood is emptied. However, it did not specify at what point the heart should be weighed or how the blood should be emptied. This study compared heart weights at three different time points during the heart examination (immediately after dissecting out of the pericardial sac with blood still in chambers, blood washed/removed from heart chambers without the heart opened, and the heart completely opened, blood emptied, and pad dried). This was to illustrate the variation in measurement and potential errors when the heart is weighed at different time of dissection. The results show that there were statistical and clinical significant differences between the heart weights at each weighing points. We recommend the heart to be completely dissected with any blood and residual washing/rinsing water emptied before being weighed. Although performed in this study, the effect of pad drying the heart on heart weight was not explored and was a limitation in this study.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Autopsy; Dissection; Female; Humans; Male; Middle Aged; Myocardium; Organ Size; Young Adult
PubMed: 32396225
DOI: 10.1111/1556-4029.14451 -
European Surgical Research. Europaische... 2014The water jet technique dissects tissue while sparing cord-like structures such as blood vessels. The mechanism of such tissue-selective dissection has been unknown. The...
The dissection profile and mechanism of tissue-selective dissection of the piezo actuator-driven pulsed water jet as a surgical instrument: laboratory investigation using Swine liver.
BACKGROUND/PURPOSE
The water jet technique dissects tissue while sparing cord-like structures such as blood vessels. The mechanism of such tissue-selective dissection has been unknown. The novel piezo actuator-driven pulsed water jet (ADPJ) system can achieve dissection with remarkably reduced water consumption compared to the conventional water jet; however, the system's characteristics and dissection capabilities on any organ have not been clarified. The purposes of this study were to characterize the physical properties of the novel ADPJ system, evaluate the dissection ability in swine organs, and reveal the mechanism of tissue-selective dissection.
METHODS
The pulsed water jet system comprised a pump chamber driven by a piezo actuator, a stainless steel tube, and a nozzle. The peak pressure of the pulsed water jet was measured through a sensing hole using a pressure sensor. The pulsed water jet technique was applied on swine liver in order to dissect tissue on a moving table using one-way linear ejection at a constant speed. The dissection depth was measured with light microscopy and evaluated histologically. The physical properties of swine liver were evaluated by breaking strength tests using tabletop universal testing instruments. The liver parenchyma was also cut with three currently available surgical devices to compare the histological findings.
RESULTS
The peak pressure of the pulsed water jet positively correlated with the input voltage (R(2) = 0.9982, p < 0.0001), and this was reflected in the dissection depth. The dissection depth negatively correlated with the breaking strength of the liver parenchyma (R(2) = 0.6694, p < 0.0001). The average breaking strengths of the liver parenchyma, hepatic veins, and Glisson's sheaths were 1.41 ± 0.45, 8.66 ± 1.70, and 29.6 ± 11.0 MPa, respectively. The breaking strength of the liver parenchyma was significantly lower than that of the hepatic veins and Glisson's sheaths. Histological staining confirmed that the liver parenchyma was selectively dissected, preserving the hepatic veins and Glisson's sheaths in contrast to what is commonly observed with electrocautery or ultrasonic instruments.
CONCLUSIONS
The dissection depth of liver tissue is well controlled by input voltage and is influenced by the moving velocity and the physical properties of the organ. We showed that the device can be used to assure liver resection with tissue selectivity due to tissue-specific physical properties. Although this study uses an excised organ, further in vivo studies are necessary. The present work demonstrates that this device may function as an alternative tool for surgery due to its good controllability of the dissection depth and ability of tissue selectivity.
Topics: Animals; Dissection; Liver; Piezosurgery; Swine
PubMed: 25139450
DOI: 10.1159/000365288 -
Advances in Experimental Medicine and... 2023In the post-pandemic era, one of the significant challenges for anatomy teachers is to reciprocate the experience of practical exposure while teaching the subject to...
In the post-pandemic era, one of the significant challenges for anatomy teachers is to reciprocate the experience of practical exposure while teaching the subject to undergraduates. These challenges span from conducting cadaveric dissections to handling real human bones, museum specimens, and tissue sections in the histology lab. Such exposures help the instructors to develop interactive communication with their fellow students and thus help to enhance communication skills among them. Recently, anatomy teachers all over the world started using cutting-edge educational technologies to make teaching-learning experiences for students more engaging, interesting, and interactive. Utilizing such cutting-edge educational technologies was an "option" prior to the pandemic, but the pandemic has significantly altered the situation. What was previously an "option" is now a "compulsion." Despite the fact that the majority of medical schools have resumed their regular on-campus classes, body donation and the availability of cadavers remain extremely limited, resulting in a deadlock. Anatomy teachers must incorporate cutting-edge educational technologies into their teaching and learning activities to make the subject more visual. In this chapter, we have attempted to discuss various new technologies which can provide a near-realistic perception of anatomical structures as a complementary tool for dissection/cadaver, various visualization techniques currently available and explore their importance as a pedagogic alternative in learning anatomy. We also discussed the recent advancement in visualization techniques and the pros and cons of technology-based visualization. This chapter identifies the limitations of technology-based visualization as a supplement and discusses effective utilization as an adjunct to the conventional pedagogical approaches to undergraduate anatomy education.
Topics: Humans; Curriculum; Education, Medical, Undergraduate; Students, Medical; Learning; Dissection; Cadaver
PubMed: 37016115
DOI: 10.1007/978-3-031-26462-7_8 -
JAMA Jan 2023
Topics: Anatomy; Dissection; Germany; History, 20th Century; National Socialism
PubMed: 36648461
DOI: 10.1001/jama.2022.23531 -
Anatomical Sciences Education 2023The anatomy laboratory can incite strong emotional reactions in students, which can in turn facilitate growth in empathy, care for vulnerable others, and...
The anatomy laboratory can incite strong emotional reactions in students, which can in turn facilitate growth in empathy, care for vulnerable others, and professionalism. Despite this, little is known about the relative emotional impacts of different laboratory modalities. The response to the COVID-19 pandemic created an opportunity to compare the emotional experiences of students in similar courses in which one group of students dissected donors and the other group learned from prosected donors. The courses were otherwise the same in content, length, instructional design, and assessment. Students in the dissection-based (Fall 2019) and prosection-based (Fall 2020) courses completed a previously validated survey that used quantitative and qualitative questions to assess their feelings about the donors and the anatomy laboratory experience. Students in both cohorts reported overall appreciation for having had the experience. Negative themes experienced by both groups included feeling anxiety, worries about depersonalizing donors, and physical discomfort in the laboratory. Students in the dissection course reported stronger connections with the donors and the donors' families but also more frequently felt negative feelings such as disgust, anxiety, and feeling alone. Students in the prosection course reported more consistently positive responses but worried about not using the donors to the fullest extent possible. Regardless of pedagogical design, students have complex emotional experiences in the anatomy laboratory and our results indicate that these feelings may be more intense in the context of dissection. Anatomists should foster educational settings that enable students to learn to process complex or challenging emotions.
Topics: Humans; Anatomy; Pandemics; Students, Medical; Dissection; Emotions; Education, Medical, Undergraduate; Cadaver
PubMed: 37060250
DOI: 10.1002/ase.2281 -
Academic Medicine : Journal of the... Aug 2023Despite numerous pedagogical approaches and technologies now available for medical gross anatomy, students can find it difficult to translate what occurs in a dissection...
PROBLEM
Despite numerous pedagogical approaches and technologies now available for medical gross anatomy, students can find it difficult to translate what occurs in a dissection laboratory into the context of clinical practice.
APPROACH
Using complementary and collaborative approaches at 2 different medical schools, Virginia Commonwealth University (VCU) and University of Maryland (UM), we designed and implemented a series of clinical activities in the preclerkship medical gross anatomy laboratory that directly link dissected structures to clinical procedures. These activities specifically direct students to perform simulated clinically related procedures on anatomic donors during laboratory dissection sessions. The activities are called OpNotes at VCU and Clinical Exercises at UM. Each activity in the VCU OpNotes requires about 15 minutes of group activity at the end of a scheduled laboratory and involves faculty to grade the student responses submitted via a web-based-assessment form. Each exercise in UM Clinical Exercises also requires about 15 minutes of group activity during the schedule laboratory but does not involve faculty to complete grading.
OUTCOMES
Cumulatively, the activities in OpNotes and Clinical Exercises both brought clinical context directly to anatomical dissections. These activities began in 2012 at UM and 2020 at VCU, allowing a multiyear and multi-institute development and testing of this innovative approach. Student participation was high, and perception of its effectiveness was almost uniformly positive.
NEXT STEPS
Future iterations of the program will work to assess the efficacy of the program as well as to streamline the scoring and delivery of the formative components. Collectively, we propose that the concept of executing clinic-like procedures on donors in anatomy courses is an effective means of enhancing learning in the anatomy laboratory while concurrently underscoring the relevance of basic anatomy to future clinical practice.
Topics: Humans; Curriculum; Dissection; Learning; Educational Measurement; Faculty; Anatomy; Education, Medical, Undergraduate; Students, Medical; Cadaver
PubMed: 36972133
DOI: 10.1097/ACM.0000000000005216 -
Journal of Animal Science Feb 1976
Topics: Animals; Cattle; Dissection; Reticulum; Rumen
PubMed: 1262269
DOI: 10.2527/jas1976.422535x -
Surgery Today Jun 2014Multiple energy-based surgical dissection and coagulation modalities are available to facilitate surgical dissection and hemostasis, but there is limited information... (Comparative Study)
Comparative Study
PURPOSE
Multiple energy-based surgical dissection and coagulation modalities are available to facilitate surgical dissection and hemostasis, but there is limited information regarding the acute tissue effects of these devices. Our objective was to compare the functional characteristics and tissue effects of four energy-based surgical dissection and coagulation modalities on the rabbit liver.
METHODS
Linear incisions were created in the rabbit liver using monopolar electrocautery, a harmonic scalpel, a PlasmaBlade and a new ferromagnetic induction loop device. Subjective cutting and coagulation characteristics for each device were recorded, and the histological tissue effects were evaluated.
RESULTS
Each of the modalities successfully incised the liver tissue. The PlasmaBlade and the ferromagnetic induction loop exhibited significantly less perceived tissue drag during the incision, significantly less collateral tissue damage and significantly better margin uniformity than the monopolar electrocautery device. Each device showed comparable subjective hemostasis. The harmonic scalpel did not demonstrate a significant difference compared with any of the other devices in any of the parameters examined. The histological analysis revealed that the least lateral thermal damage resulted when the PlasmaBlade, harmonic scalpel and ferromagnetic induction loop were used, and the most damage occurred with the use of monopolar electrocautery.
CONCLUSIONS
Each of the newer energy-based surgical tools showed improvement over monopolar electrocautery with regard to lateral thermal injury, and the ferromagnetic induction device and the PlasmaBlade demonstrated superior surgical tissue handling characteristics to the monopolar electrocautery device.
Topics: Animals; Dissection; Electrocoagulation; Liver; Rabbits
PubMed: 24006128
DOI: 10.1007/s00595-013-0712-4 -
Journal of Anatomy Oct 2011Classical fiber dissection of post mortem human brains enables us to isolate a fiber tract by removing the cortex and overlying white matter. In the current work, a...
Classical fiber dissection of post mortem human brains enables us to isolate a fiber tract by removing the cortex and overlying white matter. In the current work, a modification of the dissection methodology is presented that preserves the cortex and the relationships within the brain during all stages of dissection, i.e. 'cortex-sparing fiber dissection'. Thirty post mortem human hemispheres (15 right side and 15 left side) were dissected using cortex-sparing fiber dissection. Magnetic resonance imaging study of a healthy brain was analyzed using diffusion tensor imaging (DTI)-based tractography software. DTI fiber tract reconstructions were compared with cortex-sparing fiber dissection results. The fibers of the superior longitudinal fasciculus (SLF), inferior fronto-occipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF) and uncinate fasciculus (UF) were isolated so as to enable identification of their cortical terminations. Two segments of the SLF were identified: first, an indirect and superficial component composed of a horizontal and vertical segment; and second, a direct and deep component or arcuate fasciculus. The IFOF runs within the insula, temporal stem and sagittal stratum, and connects the frontal operculum with the occipital, parietal and temporo-basal cortex. The UF crosses the limen insulae and connects the orbito-frontal gyri with the anterior temporal lobe. Finally, a portion of the ILF was isolated connecting the fusiform gyrus with the occipital gyri. These results indicate that cortex-sparing fiber dissection facilitates study of the 3D anatomy of human brain tracts, enabling the tracing of fibers to their terminations in the cortex. Consequently, it is an important tool for neurosurgical training and neuroanatomical research.
Topics: Aged; Aged, 80 and over; Brain; Dissection; Humans; Nerve Fibers; Neural Pathways
PubMed: 21767263
DOI: 10.1111/j.1469-7580.2011.01414.x -
Journal of Visualized Experiments : JoVE Dec 2016There is an increasing interest in using Drosophila to model human brain degenerative diseases, map neuronal circuitries in adult brains, and study the molecular and...
There is an increasing interest in using Drosophila to model human brain degenerative diseases, map neuronal circuitries in adult brains, and study the molecular and cellular basis of higher brain functions. A whole-mount preparation of adult brains with well-preserved morphology is critical for such whole brain-based studies, but can be technically challenging and time-consuming. This protocol describes an easy-to-learn, one-step dissection approach of an adult fly head in less than 10 s, while keeping the intact brain attached to the rest of the body to facilitate subsequent processing steps. The procedure helps remove most of the eye and tracheal tissues normally associated with the brain that can interfere with the later imaging step, and also places less demand on the quality of the dissecting forceps. Additionally, we describe a simple method that allows convenient flipping of the mounted brain samples on a coverslip, which is important for imaging both sides of the brains with similar signal intensity and quality. As an example of the protocol, we present an analysis of dopaminergic (DA) neurons in adult brains of WT (w) flies. The high efficacy of the dissection method makes it particularly useful for large-scale adult brain-based studies in Drosophila.
Topics: Animals; Brain; Dissection; Drosophila; Head
PubMed: 27929474
DOI: 10.3791/55128