Conditionally t-diagnosable and t-diagnosable are important in system level diagnosis. Therefore,it is valuable to identify whether the system is conditionally t-diagnosable or t-diagnosable and derive the correspondi...Conditionally t-diagnosable and t-diagnosable are important in system level diagnosis. Therefore,it is valuable to identify whether the system is conditionally t-diagnosable or t-diagnosable and derive the corresponding conditional diagnosability and diagnosability. In the paper,distinguishable measures of pairs of distinct faulty sets with a new perspective on establishing functions are focused.Applying distinguishable function and decision function,it is determined whether a system is conditionally t-diagnosable( or t-diagnosable) or not under the PMC( Preparata,Metze,and Chien)model directly. Based on the decision function,a novel conditional diagnosability algorithm under the PMC model is introduced which can calculate conditional diagnosability rapidly.展开更多
For bounded Petri nets, Cabasino et al. propose a diagnosability test method that is based on the analysis of a modified basis reachability graph and a basis reachability diagnoser. However, its complexity is exponent...For bounded Petri nets, Cabasino et al. propose a diagnosability test method that is based on the analysis of a modified basis reachability graph and a basis reachability diagnoser. However, its complexity is exponential in the number of nodes of the basis reachability diagnoser. In order to reduce the complexity of their method, this paper presents a new diagnosability test approach for bounded Petri nets. We present the concept of an extended basis reachability graph and prove that our approach is of polynomial complexity in the number of nodes of extended basis reachability graphs. An example is given to illustrate the application of the presented approach.展开更多
Up to present,the problem of the evaluation of fault diagnosability for nonlinear systems has been investigated by many researchers.However,no attempt has been done to evaluate the diagnosability of multiple faults oc...Up to present,the problem of the evaluation of fault diagnosability for nonlinear systems has been investigated by many researchers.However,no attempt has been done to evaluate the diagnosability of multiple faults occurring simultaneously for nonlinear systems.This paper proposes a method based on differential geometry theories to solve this problem.Then the evaluation of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is achieved.To deal with the effect of control laws on the evaluation results of fault diagnosability,a design scheme of the evaluation of fault diagnosability is proposed.Then the influence of uncertainties on the evaluation results of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is analyzed.The numerical simulation results are obtained to show the effectiveness of the proposed evaluation scheme of fault diagnosability.展开更多
Diagnosability of a multiprocessor system is one important study topic. In 2012,Peng et al. proposed the g-good-neighbor diagnosability that restrains every fault-free nodeto contain at least g fault-free neighbors. T...Diagnosability of a multiprocessor system is one important study topic. In 2012,Peng et al. proposed the g-good-neighbor diagnosability that restrains every fault-free nodeto contain at least g fault-free neighbors. The locally twisted cube LTQn has many goodproperties. In this paper, we show that the 1-good-neighbor connectivity al （LTQn） =2n-2and the 1-good-neighbor diagnosability of LTQn is 2n - 1 under the PMC model for n ≥ 4and the MM model for n ≥ 5.展开更多
In a multiprocessor systems, it is important to local and to replace the faulty processors to maintain systempsilas high reliability. The fault diagnosis, which is the process of identifying fault processors in a mult...In a multiprocessor systems, it is important to local and to replace the faulty processors to maintain systempsilas high reliability. The fault diagnosis, which is the process of identifying fault processors in a multiprocessor system through testing. The conditional diagnosis requires that for each processor u in a system, all the processors that are directly connected to u do not fail at the same time. In this paper, we study the conditional diagnosability of the n-dimensional locally twisted cubes. After showing some properties of the locally twisted cubes, we prove that it under the PMC model is 4n – 7 for n ≥ 5.展开更多
Diagnosability of a multiprocessor system G is one important measure of the reliability of interconnection networks. In 2016, Zhang et al. proposed the g-extra diagnosability of G, which restrains that every component...Diagnosability of a multiprocessor system G is one important measure of the reliability of interconnection networks. In 2016, Zhang et al. proposed the g-extra diagnosability of G, which restrains that every component of G – S has at least (g + 1) vertices. The locally twisted cube LTQn is applied widely. In this paper, we show that LTQn is tightly (4n – 9) super 3-extra connected for n ≥ 6 and the 3-extra diagnosability of LTQn under the PMC model and MM* model is 4n - 6 for n ≥ 5 and n ≥ 7, respectively.展开更多
Diagnosability of a multiprocessor system is one important study topic. In 2012, Peng et al. proposed a measure for fault tolerance of the system, which is called the g-good-neighbor diagnosability that restrains ever...Diagnosability of a multiprocessor system is one important study topic. In 2012, Peng et al. proposed a measure for fault tolerance of the system, which is called the g-good-neighbor diagnosability that restrains every fault-free node containing at least g fault-free neighbors. In 2015, Zhang et al. proposed a measure for fault diagnosis of the system, namely, g-extra diagnosability, which restrains that every fault-free component has at least g+1 fault-free nodes. In this paper, we obtain some properties of the g-good-neighbor (g-extra) diagnosability of the system and give the g-good-neighbor (g-extra) diagnosability of some graphs under the PMC model and MM<sup>*</sup> model.展开更多
This paper describes, by means of a Voronoi hypersphere, the nearest neighbor relations of all the feature submatrices in the fault classification space and analyses the deviation disturbance angles between fault feat...This paper describes, by means of a Voronoi hypersphere, the nearest neighbor relations of all the feature submatrices in the fault classification space and analyses the deviation disturbance angles between fault feature submatrices and a k-dimension unitary matrix of the measured voltage change matrix. With the above two concepts, this paper discusses the diagnos-ability in the fault classification approach. The paper also classifies and defines the fault diagnosis problems. Finally, the paper derives the corresponding necessary and sufficient conditions for correct location of faults.展开更多
Diagnosability of a multiprocessor system is one important study topic. In 2015, Zhang et al. proposed a new measure for fault diagnosis of the system, namely, g-extra diagnosability, which restrains that every fault-...Diagnosability of a multiprocessor system is one important study topic. In 2015, Zhang et al. proposed a new measure for fault diagnosis of the system, namely, g-extra diagnosability, which restrains that every fault-free component has at least (g + 1) fault-free nodes. As a favorable topology structure of interconnection networks, the n-dimensional alternating group graph AGn has many good properties. In this paper, we give that the 2-extra diagnosability of AGn is 6n - 17 for n≥ 5 under the PMC model and MM* model.展开更多
The diagnosability of a multiprocessor system or an interconnection network is an important research topic. The system and an interconnection network have an underlying topology, which is usually presented by a graph....The diagnosability of a multiprocessor system or an interconnection network is an important research topic. The system and an interconnection network have an underlying topology, which is usually presented by a graph. In this paper, we show proof for the g-good-neighbor diagnosability of the exchanged hypercube EH (s,t) under the PMC model and MM* model.展开更多
Fault diagnosis is an important area of study with regard to the design and maintenance of multiprocessor systems.A new measure for fault diagnosis of systems,namely,non-inclusive diagnosability(denoted by MM^(*)),was...Fault diagnosis is an important area of study with regard to the design and maintenance of multiprocessor systems.A new measure for fault diagnosis of systems,namely,non-inclusive diagnosability(denoted by MM^(*)),was proposed by Ding et al.In this paper,we establish the non-inclusive diagnosability of a class of regular graphs under the PMC model and the MM^(*)model.As applications,the non-inclusive diagnosabilities of hypercubes,hierarchical hypercubes,folded hypercubes,star graphs,bubble-sort graphs,pancake graphs and dual cubes are determined under the PMC model and the[Math Processing Error]model.展开更多
The reliability of a network is an important indicator for maintaining communication and ensuring its stable operation. Therefore, the assessment of reliability in underlying interconnection networks has become an inc...The reliability of a network is an important indicator for maintaining communication and ensuring its stable operation. Therefore, the assessment of reliability in underlying interconnection networks has become an increasingly important research issue. However, at present, the reliability assessment of many interconnected networks is not yet accurate,which inevitably weakens their fault tolerance and diagnostic capabilities. To improve network reliability,researchers have proposed various methods and strategies for precise assessment. This paper introduces a novel family of interconnection networks called general matching composed networks(gMCNs), which is based on the common characteristics of network topology structure. After analyzing the topological properties of gMCNs, we establish a relationship between super connectivity and conditional diagnosability of gMCNs. Furthermore, we assess the reliability of g MCNs, and determine the conditional diagnosability of many interconnection networks.展开更多
In the work of Peng et al.(Appl Math Comput 218(21):10406–10412,2012),a new measure was proposed for fault diagnosis of systems:namely g-goodneighbor conditional diagnosability,which requires that any fault-free vert...In the work of Peng et al.(Appl Math Comput 218(21):10406–10412,2012),a new measure was proposed for fault diagnosis of systems:namely g-goodneighbor conditional diagnosability,which requires that any fault-free vertex has at least g fault-free neighbors in the system.In this paper,we establish the g-goodneighbor conditional diagnosability of locally twisted cubes under the PMC model and the MM∗model.展开更多
Diagnosability of a multiprocessor system is one important study topic.Cayley graph network Cay(T_n,S_n) generated by transposition trees Tnis one of the attractive underlying topologies for the multiprocessor system....Diagnosability of a multiprocessor system is one important study topic.Cayley graph network Cay(T_n,S_n) generated by transposition trees Tnis one of the attractive underlying topologies for the multiprocessor system.In this paper,it is proved that diagnosability of Cay(T_n,S_n) is n-1 under the comparison diagnosis model for n ≥ 4.展开更多
BACKGROUND Esophageal cysts are relatively rare in clinical practice,with most of the literature comprising case reports.Esophageal cysts protruding into the thyroid gland are easily misdiagnosed as thyroid tumors.No ...BACKGROUND Esophageal cysts are relatively rare in clinical practice,with most of the literature comprising case reports.Esophageal cysts protruding into the thyroid gland are easily misdiagnosed as thyroid tumors.No such cases have been reported so far.CASE SUMMARY This article reports the case of a 31-year-old adult male diagnosed with thyroid nodules before admission.The patient underwent left thyroidectomy and isthmusectomy.During the surgery,esophageal cysts were identified in the esophageal muscle and thyroid glands.The pathology results confirmed a nodular goiter combined with esophageal cysts.Postoperatively,the patient developed a neck infection and underwent another operation and broad-spectrum antibiotic treatment for recovery.CONCLUSION We report the first clinical case of an esophageal cyst located within the thyroid gland that was successfully treated surgically.Esophageal cyst located within the thyroid gland cause difficulties in diagnosis.In the present study,the contents of the esophageal cysts were calcified foci,and a small amount of fluid mixture,which were easily misdiagnosed as thyroid nodules and misled the surgical methods.展开更多
The growing size of the multiprocessor systems increases their vulnerability to component failures. It is crucial to local and to replace the fault processors to maintain system's high reliability. The fault diagn...The growing size of the multiprocessor systems increases their vulnerability to component failures. It is crucial to local and to replace the fault processors to maintain system's high reliability. The fault diagnosis is the process of identifying faulty processors in a system through testing. This paper establishes the diagnosabilities of the incomplete star graph Sn (n≥4) with missing links under the PMC model and its variant, the BGM model, and shows that the diagnosabilities of incomplete star graph Sn under these two diagnostic models can be determined by the minimum degree of its topology structure. This method can also be applied to the other existing multiprocessor systems.展开更多
The diagnosability of discrete event systems has been a topic of interest to many researchers. The diagnosability conditions for various systems have evolved based on a regularity condition that is imposed on faulty t...The diagnosability of discrete event systems has been a topic of interest to many researchers. The diagnosability conditions for various systems have evolved based on a regularity condition that is imposed on faulty traces with respect to their observable continuations. Improving upon this weak but necessary condition, a new model of diagnosability that is based on sensor outputs, which are called observatio ns, upon a command in put is proposed in this paper. Necessary and sufficient con ditions are derived for the proposed diagnosability model. The search performance of the proposed diagnosability condition is of linear complexity in terms of the power set of the system events and observations, compared to the exponential complexity of the search with the existing diag nosability regularity condition. Moreover, a system that is not diag no sable according to the existi ng diag nosability condition may be diagnosable in the proposed diagnosability model, which includes observations.展开更多
The fault analysis of analog circuits at subnetwork-level is confronted with two essentialcore problems: (ⅰ) Is it necessary that all the torn nodes are accessible? (ⅱ) Are there any topological conditions of subnet...The fault analysis of analog circuits at subnetwork-level is confronted with two essentialcore problems: (ⅰ) Is it necessary that all the torn nodes are accessible? (ⅱ) Are there any topological conditions of subnetwork which guarantee the fault at subnetwork-level to bediagnosed correctly? This paper answers the two problems in two theorems. The conditions are necessary and almost sufficient, and if all the torn nodes are accessible, the required topological conditions can be almost satisfied automatically. This is a special situation of our research on the distribution of the accessible nodes.展开更多
BACKGROUND Hepatic perivascular epithelioid cell neoplasms(PEComas)are rare.Diagnostic and treatment experience with hepatic PEComa remains insufficient.CASE SUMMARY Three hepatic PEComa cases are reported in this pap...BACKGROUND Hepatic perivascular epithelioid cell neoplasms(PEComas)are rare.Diagnostic and treatment experience with hepatic PEComa remains insufficient.CASE SUMMARY Three hepatic PEComa cases are reported in this paper:One case of primary malignant hepatic PEComa,one case of benign hepatic PEComa,and one case of hepatic PEComa with an ovarian mature cystic teratoma.During preoperative imaging and pathological assessment of intraoperative frozen samples,patients were diagnosed with hepatocellular carcinoma(HCC),while postoperative pathology and immunohistochemistry subsequently revealed hepatic PEComa.Patients with hepatic PEComa which is misdiagnosed as HCC often require a wider surgical resection.It is easy to mistake them for distant metastases of hepatic PEComa and misdiagnosed as HCC,especially when it’s combined with tumors in other organs.Three patients eventually underwent partial hepatectomy.After 1-4 years of follow-up,none of the patients experienced recurrence or metastases.CONCLUSION A clear preoperative diagnosis of hepatic PEComa can reduce the scope of resection and prevent unnecessary injuries during surgery.展开更多
基金Supported by the National Natural Science Foundation of China(No.61562046)Science and Technology Project of Jiangxi Provincial Education Department(No.GJJ150777,GJJ160742)
文摘Conditionally t-diagnosable and t-diagnosable are important in system level diagnosis. Therefore,it is valuable to identify whether the system is conditionally t-diagnosable or t-diagnosable and derive the corresponding conditional diagnosability and diagnosability. In the paper,distinguishable measures of pairs of distinct faulty sets with a new perspective on establishing functions are focused.Applying distinguishable function and decision function,it is determined whether a system is conditionally t-diagnosable( or t-diagnosable) or not under the PMC( Preparata,Metze,and Chien)model directly. Based on the decision function,a novel conditional diagnosability algorithm under the PMC model is introduced which can calculate conditional diagnosability rapidly.
基金supported by National Natural Science Foundation of China(61134007)National Basic Research Program of China(2013CB035406)
文摘For bounded Petri nets, Cabasino et al. propose a diagnosability test method that is based on the analysis of a modified basis reachability graph and a basis reachability diagnoser. However, its complexity is exponential in the number of nodes of the basis reachability diagnoser. In order to reduce the complexity of their method, this paper presents a new diagnosability test approach for bounded Petri nets. We present the concept of an extended basis reachability graph and prove that our approach is of polynomial complexity in the number of nodes of extended basis reachability graphs. An example is given to illustrate the application of the presented approach.
基金the Natural Science Foundation of Fujian Province,China(2019J05024)the Education Department Foundation of Fujian Province,China(JAT170091).
文摘Up to present,the problem of the evaluation of fault diagnosability for nonlinear systems has been investigated by many researchers.However,no attempt has been done to evaluate the diagnosability of multiple faults occurring simultaneously for nonlinear systems.This paper proposes a method based on differential geometry theories to solve this problem.Then the evaluation of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is achieved.To deal with the effect of control laws on the evaluation results of fault diagnosability,a design scheme of the evaluation of fault diagnosability is proposed.Then the influence of uncertainties on the evaluation results of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is analyzed.The numerical simulation results are obtained to show the effectiveness of the proposed evaluation scheme of fault diagnosability.
基金supported by the National Natural Science Foundation of China(61772010)
文摘Diagnosability of a multiprocessor system is one important study topic. In 2012,Peng et al. proposed the g-good-neighbor diagnosability that restrains every fault-free nodeto contain at least g fault-free neighbors. The locally twisted cube LTQn has many goodproperties. In this paper, we show that the 1-good-neighbor connectivity al （LTQn） =2n-2and the 1-good-neighbor diagnosability of LTQn is 2n - 1 under the PMC model for n ≥ 4and the MM model for n ≥ 5.
文摘In a multiprocessor systems, it is important to local and to replace the faulty processors to maintain systempsilas high reliability. The fault diagnosis, which is the process of identifying fault processors in a multiprocessor system through testing. The conditional diagnosis requires that for each processor u in a system, all the processors that are directly connected to u do not fail at the same time. In this paper, we study the conditional diagnosability of the n-dimensional locally twisted cubes. After showing some properties of the locally twisted cubes, we prove that it under the PMC model is 4n – 7 for n ≥ 5.
文摘Diagnosability of a multiprocessor system G is one important measure of the reliability of interconnection networks. In 2016, Zhang et al. proposed the g-extra diagnosability of G, which restrains that every component of G – S has at least (g + 1) vertices. The locally twisted cube LTQn is applied widely. In this paper, we show that LTQn is tightly (4n – 9) super 3-extra connected for n ≥ 6 and the 3-extra diagnosability of LTQn under the PMC model and MM* model is 4n - 6 for n ≥ 5 and n ≥ 7, respectively.
文摘Diagnosability of a multiprocessor system is one important study topic. In 2012, Peng et al. proposed a measure for fault tolerance of the system, which is called the g-good-neighbor diagnosability that restrains every fault-free node containing at least g fault-free neighbors. In 2015, Zhang et al. proposed a measure for fault diagnosis of the system, namely, g-extra diagnosability, which restrains that every fault-free component has at least g+1 fault-free nodes. In this paper, we obtain some properties of the g-good-neighbor (g-extra) diagnosability of the system and give the g-good-neighbor (g-extra) diagnosability of some graphs under the PMC model and MM<sup>*</sup> model.
文摘This paper describes, by means of a Voronoi hypersphere, the nearest neighbor relations of all the feature submatrices in the fault classification space and analyses the deviation disturbance angles between fault feature submatrices and a k-dimension unitary matrix of the measured voltage change matrix. With the above two concepts, this paper discusses the diagnos-ability in the fault classification approach. The paper also classifies and defines the fault diagnosis problems. Finally, the paper derives the corresponding necessary and sufficient conditions for correct location of faults.
文摘Diagnosability of a multiprocessor system is one important study topic. In 2015, Zhang et al. proposed a new measure for fault diagnosis of the system, namely, g-extra diagnosability, which restrains that every fault-free component has at least (g + 1) fault-free nodes. As a favorable topology structure of interconnection networks, the n-dimensional alternating group graph AGn has many good properties. In this paper, we give that the 2-extra diagnosability of AGn is 6n - 17 for n≥ 5 under the PMC model and MM* model.
文摘The diagnosability of a multiprocessor system or an interconnection network is an important research topic. The system and an interconnection network have an underlying topology, which is usually presented by a graph. In this paper, we show proof for the g-good-neighbor diagnosability of the exchanged hypercube EH (s,t) under the PMC model and MM* model.
基金supported by the National Natural Science Foundation of China(No.11571044)the Natural Science Foundation of Shanxi Province(No.201901D211106)。
文摘Fault diagnosis is an important area of study with regard to the design and maintenance of multiprocessor systems.A new measure for fault diagnosis of systems,namely,non-inclusive diagnosability(denoted by MM^(*)),was proposed by Ding et al.In this paper,we establish the non-inclusive diagnosability of a class of regular graphs under the PMC model and the MM^(*)model.As applications,the non-inclusive diagnosabilities of hypercubes,hierarchical hypercubes,folded hypercubes,star graphs,bubble-sort graphs,pancake graphs and dual cubes are determined under the PMC model and the[Math Processing Error]model.
基金supported by National Natural Science Foundation of China (No.62362005)。
文摘The reliability of a network is an important indicator for maintaining communication and ensuring its stable operation. Therefore, the assessment of reliability in underlying interconnection networks has become an increasingly important research issue. However, at present, the reliability assessment of many interconnected networks is not yet accurate,which inevitably weakens their fault tolerance and diagnostic capabilities. To improve network reliability,researchers have proposed various methods and strategies for precise assessment. This paper introduces a novel family of interconnection networks called general matching composed networks(gMCNs), which is based on the common characteristics of network topology structure. After analyzing the topological properties of gMCNs, we establish a relationship between super connectivity and conditional diagnosability of gMCNs. Furthermore, we assess the reliability of g MCNs, and determine the conditional diagnosability of many interconnection networks.
基金This research was supported by the National Natural Science Foundation of China(Nos.11571044 and 61373021)the Fundamental Research Funds for the Central University of China.
文摘In the work of Peng et al.(Appl Math Comput 218(21):10406–10412,2012),a new measure was proposed for fault diagnosis of systems:namely g-goodneighbor conditional diagnosability,which requires that any fault-free vertex has at least g fault-free neighbors in the system.In this paper,we establish the g-goodneighbor conditional diagnosability of locally twisted cubes under the PMC model and the MM∗model.
基金supported by the National Natural Science Foundation of China(61370001,U1304601)
文摘Diagnosability of a multiprocessor system is one important study topic.Cayley graph network Cay(T_n,S_n) generated by transposition trees Tnis one of the attractive underlying topologies for the multiprocessor system.In this paper,it is proved that diagnosability of Cay(T_n,S_n) is n-1 under the comparison diagnosis model for n ≥ 4.
基金Supported by The Research Project of Guangzhou Science and Technology Plan,No.2024A03J0042.
文摘BACKGROUND Esophageal cysts are relatively rare in clinical practice,with most of the literature comprising case reports.Esophageal cysts protruding into the thyroid gland are easily misdiagnosed as thyroid tumors.No such cases have been reported so far.CASE SUMMARY This article reports the case of a 31-year-old adult male diagnosed with thyroid nodules before admission.The patient underwent left thyroidectomy and isthmusectomy.During the surgery,esophageal cysts were identified in the esophageal muscle and thyroid glands.The pathology results confirmed a nodular goiter combined with esophageal cysts.Postoperatively,the patient developed a neck infection and underwent another operation and broad-spectrum antibiotic treatment for recovery.CONCLUSION We report the first clinical case of an esophageal cyst located within the thyroid gland that was successfully treated surgically.Esophageal cyst located within the thyroid gland cause difficulties in diagnosis.In the present study,the contents of the esophageal cysts were calcified foci,and a small amount of fluid mixture,which were easily misdiagnosed as thyroid nodules and misled the surgical methods.
基金the Foundation of Fujian Provincial Department of Science & Technology (No. 2006F5035)the National Natural Science Foundation of China (No. 60502047)
文摘The growing size of the multiprocessor systems increases their vulnerability to component failures. It is crucial to local and to replace the fault processors to maintain system's high reliability. The fault diagnosis is the process of identifying faulty processors in a system through testing. This paper establishes the diagnosabilities of the incomplete star graph Sn (n≥4) with missing links under the PMC model and its variant, the BGM model, and shows that the diagnosabilities of incomplete star graph Sn under these two diagnostic models can be determined by the minimum degree of its topology structure. This method can also be applied to the other existing multiprocessor systems.
文摘The diagnosability of discrete event systems has been a topic of interest to many researchers. The diagnosability conditions for various systems have evolved based on a regularity condition that is imposed on faulty traces with respect to their observable continuations. Improving upon this weak but necessary condition, a new model of diagnosability that is based on sensor outputs, which are called observatio ns, upon a command in put is proposed in this paper. Necessary and sufficient con ditions are derived for the proposed diagnosability model. The search performance of the proposed diagnosability condition is of linear complexity in terms of the power set of the system events and observations, compared to the exponential complexity of the search with the existing diag nosability regularity condition. Moreover, a system that is not diag no sable according to the existi ng diag nosability condition may be diagnosable in the proposed diagnosability model, which includes observations.
基金Project supported by the National Natural Science Foundation of China
文摘The fault analysis of analog circuits at subnetwork-level is confronted with two essentialcore problems: (ⅰ) Is it necessary that all the torn nodes are accessible? (ⅱ) Are there any topological conditions of subnetwork which guarantee the fault at subnetwork-level to bediagnosed correctly? This paper answers the two problems in two theorems. The conditions are necessary and almost sufficient, and if all the torn nodes are accessible, the required topological conditions can be almost satisfied automatically. This is a special situation of our research on the distribution of the accessible nodes.
文摘BACKGROUND Hepatic perivascular epithelioid cell neoplasms(PEComas)are rare.Diagnostic and treatment experience with hepatic PEComa remains insufficient.CASE SUMMARY Three hepatic PEComa cases are reported in this paper:One case of primary malignant hepatic PEComa,one case of benign hepatic PEComa,and one case of hepatic PEComa with an ovarian mature cystic teratoma.During preoperative imaging and pathological assessment of intraoperative frozen samples,patients were diagnosed with hepatocellular carcinoma(HCC),while postoperative pathology and immunohistochemistry subsequently revealed hepatic PEComa.Patients with hepatic PEComa which is misdiagnosed as HCC often require a wider surgical resection.It is easy to mistake them for distant metastases of hepatic PEComa and misdiagnosed as HCC,especially when it’s combined with tumors in other organs.Three patients eventually underwent partial hepatectomy.After 1-4 years of follow-up,none of the patients experienced recurrence or metastases.CONCLUSION A clear preoperative diagnosis of hepatic PEComa can reduce the scope of resection and prevent unnecessary injuries during surgery.
