Study on the damage of primary branches of the Glisson system in the hepatic portal by argon plasma coagulation with different spraying time / 中华肝胆外科杂志

Objective:To investigate the effect of different spray-coagulation time of argon plasma coagulation (APC) injury on the Glisson system primary branche(G1) in the hepatic portal of pigs.Methods:Fifty clean healthy domestic pigs (27 females and 23 males, aged 7 to 14 months) were selected, with the body weighted (100.0±9.5) kg. They were randomly divided into five groups (A, B, C, D, and E), with 10 pigs in each group. G1 models were made and sprayed by APC for 1, 2, 3, 4, and 5 seconds. The damage, maximum damage area, maximum damage depth, and damage of the three branches of the Glisson system (the first branches of the portal vein, intrahepatic bile duct, and hepatic artery) were compared among the groups. The pigs were divided into two groups based on whether the three branches were damaged or not: the three-branch damage group ( n=23) and the control group ( n=27). The maximum damage area and maximum damage depth were compared between the two groups. Results:After the APC spraying, circular or elliptical damage appeared on the surface of the G1, with changes such as yellow-brown color, brown color, charred appearance, and defects. Under the microscope, G1 capsule was found to be deficient, the fibrous tissue beneath the capsule was ruptured, and the structures of small blood vessels and small bile ducts were incomplete. " Burn marks" and damage to the three branches of the Glisson system in G1 were also observed, and the damage was more severe at the center of the spray-coagulation. As the spray-coagulation time increased, the maximum damage area of the G1 model also increased, and the two were positively correlated ( r=0.90, P<0.001). The maximum damage depth was also positively correlated with spray-coagulation time ( r=0.97, P<0.001). The numbers of pigs with damage to the three branches of the Glisson system in Groups A-E were 0, 2, 5, 6, and 10, respectively, and the number of pigs with damage increased with the spray-coagulation time. In the three-branch damage group, the spray-coagulation time, maximum damage area, and maximum damage depth were all higher than those in the control group (without three-branch damage), and the differences were statistically significant (all P<0.05). Conclusion:The degree of damage to G1 caused by APC is positively correlated with the spray-coagulation time, and damage to the three branches of the Glisson system in G1 is related to the maximum damage area, maximum damage depth, and APC spray-coagulation time.

Design, Simulation and Experimental Study of a Novel Radiofrequency Tissue Welding Electrode / 医用生物力学

Objective Aiming at improving biomechanical strength of the anastomotic stoma as well as reducing tissue thermal damage, a novel radiofrequency (RF) tissue welding electrode was developed. Methods A novel electrode with a hollow structure on the surface ( the plum electrode) was designed and the ring electrode was used as control group to conduct the welding of intestinal tissues based on RF energy. Biomechanical properties of anastomotic stoma were studied by shear test and burst pressure test. The tissue thermal damage during welding was investigated by finite element electro-thermal-mechanical multi-field coupling simulation analysis and thermocouple probe, and the tissue microstructures were also studied. Results Under 120 W RF energy, 8 s welding duration and 20 kPa compression pressure, the anastomotic stoma had the optimal biomechanical properties. Compared with the ring electrode group, biomechanical strength of the anastomotic stoma in plum electrode group was higher, with the shear strength and burst pressure increasing from (9. 7±1. 47) N, (84. 0±5. 99) mmHg to (11. 1±1. 71) N, (89. 4±6. 60) mmHg, respectively. There was a significant reduction in tissue thermal damage, and intact and fully fused stomas could be formed in anastomotic area. Conclusions The proposed novel electrode could improve biomechanical strength of the anastomosis as well as reduce tissue hermal damage, thus achieve better fusion. The research result provide references for realizing the seamless connection of human lumen tissues

Effect of continuous saline irrigation during operation on the incision pain relief after posterior lumbar surgery / 解放军医学杂志

Objective: To explore the effect of continuous saline irrigation and cooling during posterior lumbar surgery using high-frequency electric knife to expose lumbar lamina on postoperative incision pain. Methods: A total of 34 adult patients with lumbar intraspinal tumor were included in present study who received surgical treatment from August 2017 to July 2018 in Changzheng Hospital Affiliated to Navy Medical University, and were randomly divided into irrigated group (n=17) and nonirrigated group (n=17). Patients in irrigated group received continuous normal saline irrigation for cooling surgical field, while those in non-irrigated group did not receive such treatment. The time required for exposure of bilateral lamina, the temperature of tissues around the electrosurgical scalpel, degree of thermal damage of muscle tissue, postoperative C-reactive protein level, the visual analogue scale (VAS) scores at 1st, 2nd and 3rd day after operation, and the amount of analgesics were compared between the two groups. Results: The time required for exposure of bilateral lamina was obviously longer in irrigated group than in nonirrigated group [(29.12±4.68) min vs. (24.94±3.23) min, P0.05) between the two groups. The VAS score and the amount of analgesics were obviously lower in irrigated group than in non-irrigated group at the 1st day after operation (P0.0.5) at the 2nd and 3rd day after operation. Conclusion: Continuous normal saline irrigation may reduce the thermal damage of muscle tissue to some extent after posterior lumbar surgery, and relieve the postoperative pain.

Comparison of the thermal damage of energy-based surgical devices during thyroid surgery / 中华内分泌外科杂志

Objective Energy based surgical devices such as high frequency electrotome,Harmonic scalpel and LigaSure are widely used in thyroid operations.This study is to demonstrate the difference of tissue thermal damage among different surgical instruments.Methods 12 beagle dogs were randomly divided into 3 groups,electrotome 15 W groups (group A),three-speed Harmonic scalpel (group B) and LigaSure middle gear group (group C).Patients of each group received energy instruments operating on their thyroid tissue which mimics traditional thyroidectomy.The temperatures of gland tissue during procedures were monitored by infrared thermal imager,and the operated thyroid tissues were histologically analyzed.Results The highest temperature was (83.9±8.2)℃ in the electrotome group,(70.7±7.5)℃ in three-speed Harmonic scalpel group,and (56.6±5.7)℃ in LigaSure group.The highest temperature among the three groups was statistically significant.The electrotome (15 W) caused more serious thermal damage to thyroid tissues than that caused by either the Harmonic scalpel or LigaSure (thermal damaged depth:(0.96±0.07) mm vs (0.74±0.07) mm,P＜0.01;(0.96±0.07) mm vs (0.72± 0.11) mm,P＜0.01).Nevertheless,the thermal damage had no significant differences between the Harmonic scalpel and LigaSure group (P=0.845).The thermal damage caused by the 15 W electrotome was significantly larger than that in the other two groups,and the difference had statistical significance (P＜0.01).Conclusion Compared to the high frequency electrotome,Harmonic scalpel and LigaSure lead less tissue thermal damage during thyroid surgeries,owing to less heat production.In that way,Harmonic scalpel and LigaSure are superior to electrotome in terms of safety.

The effect of thermal damage on the cell proliferation and invasive metastasis of HCC: an experimental study in vitro / 介入放射学杂志

Objective To evaluate the influence of thermal damage on the cell proliferation,invasive metastasis and epithelial-mesenchymal transition of hepatocellular carcinoma (HCC) through experiments in vitro,and to explore the relationship between thermal ablation and the recurrence,metastasis of HCC.Methods The McA-RH7777 HCC cell thermal damage model was established by using external heating method.The effect of thermal damage on the proliferation of HCC cells was detected by Kit-8 assay (CCK-8),and the cell cycle changes were studied by flow cytometry.The effect of thermal damage on the invasion potential of HCC cells was assessed by using Transwell assay.Fluorescence quantitative polymerase chain reaction (RT-PCR) and Western blot were used to evaluate the influence of thermal damage on HCC cell invasion potential,and on the mRNA and protein expression levels of EMT-related molecular markers,including VEGF,MMP-9,Nm23,E-cadherinand vimentin.Results Heating treatment of McA-RH7777HCC cells was performed by putting the cells in 43.5℃ water basin for 30 min.Two to five days after heating treatment the cell proliferative ability was significantly higher than that of control group (P＜0.05).At 48-72hours after heating treatment the proportion of HCC cells in G1 phase was obviously reduced and the proportion of HCC cells in S+G2 phase was significantly increased,the differences were statistically significant (P＜0.05).Compared with the control group,the difference in HCC cell invasion potential determined at 24 h after heating treatment was not significant,while the HCC cell invasion potential determined at 72 h after heating treatment was strikingly increased (22.3±2.46 vs.14.2±l.82,P＜0.001).Real-time PCR and Western blotting results indicated that at 72 h after heating treatment the expression levels of VEGF,MMP-9 and vimentin were significantly increased,while the expression level of E-cadherin was remarkably decreased,the differences were statistically significant (P＜0.05).Conclusion Thermal damage with sub-lethal heating dose can induce McA-RH7777 HCC cell to develop epithelial-mesenchymal transition and to enhance its proliferation and invasive metastasis potential,and HCC cells show higher malignant potential.

Comparison of Thermal Damage and Wound Repair in Rat Skin after Bipolar Fractional Radiofrequency and CO₂ Laser Treatment / 대한피부과학회지

BACKGROUND: Several studies have described the use of bipolar fractional radiofrequency (FRF) treatment not only to reverse aging or restore photo-damaged skin but also to treat acne and acne-related scarring with a low downtime and few potential complications. However, few histological studies have been conducted to identify the precise mechanism responsible for the success of bipolar FRF treatment. OBJECTIVE: To compare thermal tissue damage and wound repair after exposure to bipolar FRF and ablative CO₂ laser treatment. METHODS: We irradiated the skin of an albino rat (Sprague-Dawley, 200∼250 g) using a CO₂ laser and a bipolar FRF device. Biopsy specimens of the irradiated skin were collected on the first, third and fourteenth day after treatment. For histological analysis, the skin samples were stained with hematoxylin and eosin, Masson's trichrome, and Verhoeff-van Gieson stain. RESULTS: Immediately after bipolar FRF treatment, the skin samples showed coagulated columns in the dermis forming a pyramidal zone of sublative thermal injury. Three days after treatment, they showed re-epithelialization with minimal crust formation. Compared to the ablative CO₂ laser, bipolar FRF treatment showed lower epidermal disruption and more extensive dermal remodeling, with a rapid tissue repair response to the damage. CONCLUSION: With bipolar FRF treatment, wound repair is rapid with minimal recovery time and pigmentary complications. The bulk impact of coagulation and residual heating occurring deep within the dermis causes significant collagen contracture and remodeling, leading to effective improvement in skin texture and wrinkles, acne scars, and dyschromia in all skin types.

Comparison of Thermal Damage and Wound Repair in Rat Skin after Bipolar Fractional Radiofrequency and CO₂ Laser Treatment / 대한피부과학회지

BACKGROUND: Several studies have described the use of bipolar fractional radiofrequency (FRF) treatment not only to reverse aging or restore photo-damaged skin but also to treat acne and acne-related scarring with a low downtime and few potential complications. However, few histological studies have been conducted to identify the precise mechanism responsible for the success of bipolar FRF treatment. OBJECTIVE: To compare thermal tissue damage and wound repair after exposure to bipolar FRF and ablative CO₂ laser treatment. METHODS: We irradiated the skin of an albino rat (Sprague-Dawley, 200∼250 g) using a CO₂ laser and a bipolar FRF device. Biopsy specimens of the irradiated skin were collected on the first, third and fourteenth day after treatment. For histological analysis, the skin samples were stained with hematoxylin and eosin, Masson's trichrome, and Verhoeff-van Gieson stain. RESULTS: Immediately after bipolar FRF treatment, the skin samples showed coagulated columns in the dermis forming a pyramidal zone of sublative thermal injury. Three days after treatment, they showed re-epithelialization with minimal crust formation. Compared to the ablative CO₂ laser, bipolar FRF treatment showed lower epidermal disruption and more extensive dermal remodeling, with a rapid tissue repair response to the damage. CONCLUSION: With bipolar FRF treatment, wound repair is rapid with minimal recovery time and pigmentary complications. The bulk impact of coagulation and residual heating occurring deep within the dermis causes significant collagen contracture and remodeling, leading to effective improvement in skin texture and wrinkles, acne scars, and dyschromia in all skin types.

Research on thermal damage of recurrent laryngeal nerve by the high frequency electric knife / 中华内分泌外科杂志

Objective To investigate the heat effects of the high-frequency electric knife on the recurrent laryngeal nerve ( RLN) in pigs and the safety margin in which electric knife can be used .Methods Totally 12 pigs for experiment were randomly divided into 3 groups by the distance between the head of the electric knife and the nerve(2 mm, 1 mm, 0 mm).The application time of the electric knife touching RLN was set to be 3 s and the application energy of the electric knife was 90 W.The data of electromyogram were measured by means of nerve detector before and after operation .Statistical analysis was made based on those data .The nerve tissues were taken to make paraffin sections so that the histological change can be observed and compared before and after damage.Results The data from electromyogram by nerve detector indicated that the difference of the amplitude of group 2(1 mm)and group 3(0 mm)had statistical significance(P<0.05)within group.There were significant difference of the amplitude between the 3 groups.Histological study showed that the tissues of group 3(0 mm)had obvious injury .Conclusions In thyroid surgery , the safety range of high frequency electrical knife used around RLN is:the distance from electrical knife head to nerve should be no less than 2 mm.

Análise computacional do dano térmico no olho humano portador de um melanoma de coroide quando submetido à termoterapia transpupilar a laser / Computational analysis of thermal damage in the human eye carrying a choroidal melanoma when exposed to laser transpupillary thermotherapy treatment

Este trabalho apresenta um modelo bidimensional do olho humano para investigar a evolução da temperatura em estado transitório e o dano térmico associado nas camadas do olho e, principalmente, no melanoma de coroide. A modelagem e simulação computacional foram executadas para um paciente portador de um melanoma de coroide, submetido a um tratamento por irradiação com laser. Para determinar o campo de temperaturas, foi desenvolvido um modelo que utiliza a equação da biotransferência de calor de Pennes (BHTE - Bioheat Transfer Equation) que possui um termo de fonte/sumidouro que responde pelo calor transferido através da perfusão sanguínea. O modelo de Birngruber foi utilizado para determinar a função dano térmico durante a termoterapia transpupilar a laser (TTT). A análise foi efetuada a partir de uma imagem de ultrassom do paciente. Este tipo de exame forneceu as dimensões do olho e do tumor. O software comercial de CFD (Computational Fluid Dynamics) FLUENT, que emprega o Método dos Volumes Finitos (MVF), foi utilizado nas análises do modelo. Foram calculadas as temperaturas em estado estacionário para o olho não irradiado e estes resultados foram utilizados como condição inicial para a simulação de estado transitório para o olho irradiado, durante 60 segundos, com um laser de diodo (810 nm e potências de saída de 178, 222, 400 e 500 mW) cujos feixes apresentavam diâmetros de 2,0 e 3,0 mm e intensidades de 56.588 W/m² e 70.736 W/m² sobre a córnea. Para validar o modelo, os resultados das temperaturas, em estado estacionário para o olho não exposto à radiação do laser, foram comparados com outros mostrando uma boa concordância entre eles. Os resultados das temperaturas e do dano térmico, estado transitório, para o olho irradiado com o laser estão, qualitativamente, em acordo com a literatura disponível.

This paper presents a two-dimensional model of the human eye to investigate the evolution of temperature in transient state and the associated thermal damage in the layers of the eye and, especially in the choroidal melanoma. The computer modeling and simulation were performed for a patient with a choroidal melanoma, undergoing treatment by laser irradiation. To determine the temperature field, we developed a model that uses the Pennes Bioheat Transfer Equation (BHTE) that has a term of source/sink that responds to the heat transferred through the blood perfusion. The Birngruber model was used to determine the function of thermal damage during the laser transpupillary thermotherapy (TTT). The analysis was carried out from an ultrasound image of the patient. This type of examination provided the dimensions of the eye and the tumor. The CFD (Computational Fluid Dynamics) commercial software FLUENT&®, which uses the Finite Volume Method (FVM) was used in the analysis of the model. The temperatures, steady-state, were calculated for the normal eye, i.e, without laser irradiation and these results were used as initial condition for the simulation of transient state to the eye irradiated for 60 seconds with a diode laser (810 nm and output power of 178, 222, 400 and 500 mW) whose beam had a diameter of 2.0 to 3.0 mm and irradiance of 56,588 and 70,736 W/m² on the cornea. To validate the model, the results of temperatures, in steady state to the eye not exposed to laser radiation, were compared with others showing a good agreement between them. The results of thermal damage and transient state, for the eye irradiated by the laser, show that the values of damage depth are in agreement with the literature.

Quantification of thermal damage in skin tissue / 西安交通大学学报·英文版

Skin thermal damage or skin burns are the most commonly encountered type of trauma in civilian and military communities. Besides, advances in laser, microwave and similar technologies have led to recent developments of thermal treatments for disease and damage involving skin tissue, where the objective is to induce thermal damage precisely within targeted tissue structures but without affecting the surrounding, healthy tissue. Further, extended pain sensation induced by thermal damage has also brought great problem for burn patients. Thus, it is of great importance to quantify the thermal damage in skin tissue. In this paper, the available models and experimental methods for quantification of thermal damage in skin tissue are discussed.

Quantification of thermal damage in skin tissue / 药物分析学报

Skin thermal damage or skin burns are the most commonly encountered type of trauma in civilian and military communities. Besides, advances in laser, microwave and similar technologies have led to recent developments of thermal treatments for disease and damage involving skin tissue, where the objective is to induce thermal damage precisely within targeted tissue structures but without affecting the surrounding, healthy tissue. Further, extended pain sensation induced by thermal damage has also brought great problem for burn patients. Thus, it is of great importance to quantify the thermal damage in skin tissue. In this paper, the available models and experimental methods for quantification of thermal damage in skin tissue are discussed.