Cerebral cavernous malformations are a rare and congenital vascular malformation that can present as a challenge in neurosurgical management. The term “giant cerebral cavernous malformations” still does not have a c...Cerebral cavernous malformations are a rare and congenital vascular malformation that can present as a challenge in neurosurgical management. The term “giant cerebral cavernous malformations” still does not have a clear definition in the literature, with a wide variety of results. It is known, however, that there is an association between the size of the cavernoma and postoperative sequelae, especially in those with a size greater than 3 cm in its largest diameter. We present a case report of resection of a giant brain cavernoma measuring approximately 8 cm in its largest diameter, emphasizing on clinical presentation, diagnoses and postoperative evolution. Additionally, we performed a comprehensive review of the existing literature on the subject, addressing the epidemiology, pathophysiology, diagnostic methods, treatment options, and prognosis associated with this condition.展开更多
BACKGROUND Direct carotid cavernous fistulas(CCFs)are typically the result of a severe traumatic brain injury.High-flow arteriovenous shunts secondary to rupture of an intracavernous aneurysm,resulting in direct CCFs,...BACKGROUND Direct carotid cavernous fistulas(CCFs)are typically the result of a severe traumatic brain injury.High-flow arteriovenous shunts secondary to rupture of an intracavernous aneurysm,resulting in direct CCFs,are rare.The use of a pipeline embolization device in conjunction with coils and Onyx glue for treatment of direct high-flow CCF resulting from ruptured cavernous carotid artery aneurysm in a clinical setting is not well documented.CASE SUMMARY A 58-year-old woman presented to our department with symptoms of blepharoptosis and intracranial bruits for 1 wk.During physical examination,there was right eye exophthalmos and ocular motor palsy.The rest of the neurological examination was clear.Notably,the patient had no history of head injury.The patient was treated with a pipeline embolization device in the ipsilateral internal carotid artery across the fistula.Coils and Onyx were placed through the femoral venous route,followed by placement of the pipeline embolization device with assistance from a balloon-coiling technique.No intraoperative or perioperative complications occurred.Preoperative symptoms of bulbar hyperemia and bruits subsided immediately after the operation.CONCLUSION Pipeline embolization device in conjunction with coiling and Onyx may be a safe and effective approach for direct CCFs.展开更多
Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to...Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.展开更多
Underground salt cavern CO_(2) storage(SCCS)offers the dual benefits of enabling extensive CO_(2) storage and facilitating the utilization of CO_(2) resources while contributing the regulation of the carbon market.Its...Underground salt cavern CO_(2) storage(SCCS)offers the dual benefits of enabling extensive CO_(2) storage and facilitating the utilization of CO_(2) resources while contributing the regulation of the carbon market.Its economic and operational advantages over traditional carbon capture,utilization,and storage(CCUS)projects make SCCS a more cost-effective and flexible option.Despite the widespread use of salt caverns for storing various substances,differences exist between SCCS and traditional salt cavern energy storage in terms of gas-tightness,carbon injection,brine extraction control,long-term carbon storage stability,and site selection criteria.These distinctions stem from the unique phase change characteristics of CO_(2) and the application scenarios of SCCS.Therefore,targeted and forward-looking scientific research on SCCS is imperative.This paper introduces the implementation principles and application scenarios of SCCS,emphasizing its connections with carbon emissions,carbon utilization,and renewable energy peak shaving.It delves into the operational characteristics and economic advantages of SCCS compared with other CCUS methods,and addresses associated scientific challenges.In this paper,we establish a pressure equation for carbon injection and brine extraction,that considers the phase change characteristics of CO_(2),and we analyze the pressure during carbon injection.By comparing the viscosities of CO_(2) and other gases,SCCS’s excellent sealing performance is demonstrated.Building on this,we develop a long-term stability evaluation model and associated indices,which analyze the impact of the injection speed and minimum operating pressure on stability.Field countermeasures to ensure stability are proposed.Site selection criteria for SCCS are established,preliminary salt mine sites suitable for SCCS are identified in China,and an initial estimate of achievable carbon storage scale in China is made at over 51.8-77.7 million tons,utilizing only 20%-30%volume of abandoned salt caverns.This paper addresses key scientific and engineering challenges facing SCCS and determines crucial technical parameters,such as the operating pressure,burial depth,and storage scale,and it offers essential guidance for implementing SCCS projects in China.展开更多
Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An ...Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed.Firstly,the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns.Then,overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out,and the critical unstable state of multi-caverns can be identified,if the plastic-strain band appeared between caverns during these overloading processes.Thus,the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient.Practical analysis for the Yingliangbao(YLB)hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions,but also identify the caverns’high-risk zone of local instability through localized plastic strain of surrounding rock.This study can provide some reference for the layout design and seismic optimization of underground cavern group.展开更多
Underground hydrogen storage(UHS)and compressed air energy storage(CAES)are two viable largescale energy storage technologies for mitigating the intermittency of wind and solar power.Therefore,it is meaningful to comp...Underground hydrogen storage(UHS)and compressed air energy storage(CAES)are two viable largescale energy storage technologies for mitigating the intermittency of wind and solar power.Therefore,it is meaningful to compare the properties of hydrogen and air with typical thermodynamic storage processes.This study employs a multi-physical coupling model to compare the operations of CAES and UHS,integrating gas thermodynamics within caverns,thermal conduction,and mechanical deformation around rock caverns.Gas thermodynamic responses are validated using additional simulations and the field test data.Temperature and pressure variations of air and hydrogen within rock caverns exhibit similarities under both adiabatic and diabatic simulation modes.Hydrogen reaches higher temperature and pressure following gas charging stage compared to air,and the ideal gas assumption may lead to overestimation of gas temperature and pressure.Unlike steel lining of CAES,the sealing layer(fibre-reinforced plastic FRP)in UHS is prone to deformation but can effectively mitigates stress in the sealing layer.In CAES,the first principal stress on the surface of the sealing layer and concrete lining is tensile stress,whereas UHS exhibits compressive stress in the same areas.Our present research can provide references for the selection of energy storage methods.展开更多
Large‐scale underground hydrogen storage(UHS)provides a promising method for increasing the role of hydrogen in the process of carbon neutrality and energy transition.Of all the existing storage deposits,salt caverns...Large‐scale underground hydrogen storage(UHS)provides a promising method for increasing the role of hydrogen in the process of carbon neutrality and energy transition.Of all the existing storage deposits,salt caverns are recognized as ideal sites for pure hydrogen storage.Evaluation and optimization of site selection for hydrogen storage facilities in salt caverns have become significant issues.In this article,the software CiteSpace is used to analyze and filter hot topics in published research.Based on a detailed classification and analysis,a“four‐factor”model for the site selection of salt cavern hydrogen storage is proposed,encompassing the dynamic demands of hydrogen energy,geological,hydrological,and ground factors of salt mines.Subsequently,20 basic indicators for comprehensive suitability grading of the target site were screened using the analytic hierarchy process and expert survey methods were adopted,which provided a preliminary site selection system for salt cavern hydrogen storage.Ultimately,the developed system was applied for the evaluation of salt cavern hydrogen storage sites in the salt mines of Pingdingshan City,Henan Province,thereby confirming its rationality and effectiveness.This research provides a feasible method and theoretical basis for the site selection of UHS in salt caverns in China.展开更多
BACKGROUND Colorectal cavernous hemangioma is a rare vascular malformation resulting in recurrent lower gastrointestinal hemorrhage,and can be misinterpreted as colitis.Surgical resection is currently the mainstay of ...BACKGROUND Colorectal cavernous hemangioma is a rare vascular malformation resulting in recurrent lower gastrointestinal hemorrhage,and can be misinterpreted as colitis.Surgical resection is currently the mainstay of treatment,with an emphasis on sphincter preservation.CASE SUMMARY We present details of two young patients with a history of persistent hematochezia diagnosed with colorectal cavernous hemangioma by endoscopic ultrasound(EUS).Cavernous hemangioma was relieved by several EUS-guided lauromacrogol injections and the patients achieved favorable clinical prognosis.CONCLUSION Multiple sequential EUS-guided injections of lauromacrogol is a safe,effective,cost-efficient,and minimally invasive alternative for colorectal cavernous hemangioma.展开更多
BACKGROUND Patients with giant intracranial aneurysms(GIAs)are at a high risk of rupture,morbidity,and mortality even after surgical or endovascular treatment.We described a case of a spontaneously occluded GIA second...BACKGROUND Patients with giant intracranial aneurysms(GIAs)are at a high risk of rupture,morbidity,and mortality even after surgical or endovascular treatment.We described a case of a spontaneously occluded GIA secondary to gradual growth of the GIA,continuously progressed aneurysmal thrombosis,complete aneurysmal calcification and complete occlusion of the parent artery-the right internal carotid artery(RICA).CASE SUMMARY A 72-year-old female patient complained of sudden pain in her right eye upon admission to our hospital.She had been diagnosed with a GIA[30 mm(axial)×38 mm(coronal)×28 mm(sagittal)]containing an aneurysmal thrombus located in the cavernous sinus segment of RICA diagnosed by magnetic resonance imaging(MRI),enhanced MRI,and magnetic resonance angiography more than 14 years ago.Later,with slow growth of the cavernous carotid GIA,aneurysmal thrombosis progressed continuously,spontaneous occlusion of the RICA,complete aneurysmal calcification,and occlusion of the GIA occurred gradually.She had no history of subarachnoid hemorrhage but missed the chance for endovascular therapy at an early stage.As a result,she was left with severe permanent sequelae from the injuries to the right cranial nerves Ⅱ,Ⅲ,Ⅳ,V1/V2,and Ⅴ.CONCLUSION The risk of rupture of the cavernous carotid GIAs was relatively low and possibly further be reduced by the stasis flow and spontaneous occlusion of the parent artery internal carotid artery(ICA)induced by the mass effect of the cavernous carotid GIAs and the extremely rare aneurysmal calcification.However,nowadays,it is advisable to recommend early endovascular treatment for the cavernous carotid GIAs to prevent injuries to the surrounding intracranial nerves and occlusion of the ICA,mainly caused by the mass effect of the cavernous carotid GIAs.展开更多
BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in adults.As a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis.However,lymph...BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in adults.As a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis.However,lymphangiomas can give rise to complications such as abdominal pain,bleeding,volvulus,and intussusception.Here,we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male adult.CASE SUMMARY A 66-year-old man presented with intermittent melena,fatigue and refractory anemia nine months prior.Esophagogastroduodenoscopy and colonoscopy were performed many times and revealed no apparent bleeding.Conservative management,including transfusion,hemostasis,gastric acid secretion inhibition and symptomatic treatment,was performed,but the lesions tended to recur shortly after surgery.Ultimately,the patient underwent capsule endoscopy,which revealed a more than 10 cm lesion accompanied by active bleeding.After singleballoon enteroscopy and biopsy,a diagnosis of jejunal cavernous lymphangioma was confirmed,and the patient underwent surgical resection.No complications or recurrences were observed postoperatively.CONCLUSION Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal bleeding.Capsule endoscopy and single-balloon enteroscopy can facilitate diagnosis.Surgical resection is an effective management method.展开更多
Objective:To investigate the computed tomography(CT)and magnetic resonance imaging(MRI)features of cavernous hemangioma malformation(CHM)to enhance diagnostic accuracy.Methods:The CT and MRI findings and clinical info...Objective:To investigate the computed tomography(CT)and magnetic resonance imaging(MRI)features of cavernous hemangioma malformation(CHM)to enhance diagnostic accuracy.Methods:The CT and MRI findings and clinical information of 23 patients with CHM were retrospectively analyzed.Results:CT examinations were conducted in 7 cases,while MRI was utilized in 23 cases.Additionally,SWI was employed in 5 cases and enhanced imaging techniques were applied in 14 cases.Among the observed lesions,20 cases presented with a singular lesion,whereas 3 cases exhibited multiple lesions.The lesions were located in 8 frontal lobes,6 cerebellums,2 brainstems,6 temporal lobes,1 basal ganglia,3 parieto-occipital lobes,and 2 thalamus regions.The nodules appeared as quasi-circular lesions with clear or well-defined boundaries.They presented as isodense lesions on CT scans,with one lesion showing peritumoral edema.On MRI,T1-weighted imaging(T1WI)demonstrated isointense signals,while T2-weighted imaging(T2WI)showed isointense and hyperintense signals.Additionally,10 lesions exhibited a low signal ring on T2WI.Diffusion-weighted imaging(DWI)revealed nodular or isointense low signals,while susceptibility-weighted imaging(SWI)displayed enlarged areas of low signal.Fourteen lesions underwent contrast-enhanced scanning,with 2 lesions showing no obvious enhancement,1 lesion demonstrating mild to moderate enhancement,and 11 lesions exhibiting significant enhancement.Notably,6 of these enhanced lesions were surrounded by small blood vessels.Conclusion:Cavernous hemangioma malformation is more commonly found in individual cases.CT alone lacks specificity,making it prone to misdiagnosis.A more comprehensive evaluation of cavernous hemangioma malformation can be achieved through a combination of MRI,DWI,SWI,and enhanced examination,providing valuable references for clinical assessment.展开更多
The storage of hydrogen gas in underground lined rock caverns(LRCs)enables the implementation of the first fossil-free steelmaking process to meet the large demand for crude steel.Predicting the response of rock mass ...The storage of hydrogen gas in underground lined rock caverns(LRCs)enables the implementation of the first fossil-free steelmaking process to meet the large demand for crude steel.Predicting the response of rock mass is important to ensure that gas leakage due to rupture of the steel lining does not occur.Analytical and numerical models can be used to estimate the rock mass response to high internal pressure;however,the fitness of these models under different in situ stress conditions and cavern shapes has not been studied.In this paper,the suitability of analytical and numerical models to estimate the maximum cavern wall tangential strain under high internal pressure is studied.The analytical model is derived in detail and finite element(FE)models considering both two-dimensional(2D)and three-dimensional(3D)geometries are presented.These models are verified with field measurements from the LRC in Skallen,southwestern Sweden.The analytical model is inexpensive to implement and gives good results for isotropic in situ stress conditions and large cavern heights.For the case of anisotropic horizontal in situ stresses,as the conditions in Skallen,the 3D FE model is the best approach.展开更多
The hydrodynamic performance of three mixers single shaft central mixer(SSC), single shaft off-centred mixer(SSO), dual shaft off-centred mixer(DSO), was investigated in the mixing of yield-pseudoplastic fluids(xantha...The hydrodynamic performance of three mixers single shaft central mixer(SSC), single shaft off-centred mixer(SSO), dual shaft off-centred mixer(DSO), was investigated in the mixing of yield-pseudoplastic fluids(xanthan gum solutions) in the laminar regime. To explore and determine the efficiency of three mixers, both numerical and experimental approaches were adopted. The fluid rheology was described by the Herschel–Bulkley rheological model. Computational fluid dynamics was employed to simulate the apparent viscosity distribution, mixing time, and the flow pattern inside the stirred tank. The developed model was validated through experimentally measured torque. The influence mechanism of the rotational speed and fluid rheology on the cavern evolution was explored deeply. The performances of three mixers in this work were compared at the constant power input and fluid rheology with respect to the flow pattern, mixing time, and mixing efficiency. The results verify that the faster the rotating speed, the greater influence of the fluid rheology on the cavern evolution, and the more uniform apparent viscosity distribution. Moreover, the mixing time decreases continuously as the increasing power consumption per unit volume, and the dimensionless mixing time of DSO mixer was nearly 42.8% and 6.1% shorter than that of SSC and SCO mixer at the same Reynolds number, respectively. According to the mixing efficiency criteria, these data also revealed that DSO was more efficient than SSC and SSO.展开更多
Spalling is a typical brittle failure phenomenon of hard rock in deep caverns under high geostress.In this study,key issues are systematically studied concerning the spalling failure of deep hard rock caverns.First,th...Spalling is a typical brittle failure phenomenon of hard rock in deep caverns under high geostress.In this study,key issues are systematically studied concerning the spalling failure of deep hard rock caverns.First,the prismatic rock specimens with small thicknesses(i.e.width×thickness×height:20 mm×50 mm×100 mm)are employed in our tests which not only successfully simulate the spalling failure of hard rock in the laboratory but also obtain a reasonable spalling strength similar to that of the rock mass.Then,a series of spalling experiments is carried out to investigate the mechanism of spalling failure of deep hard rock caverns.Our results show that the intermediate principal stress,weak dynamic disturbances,and rock microstructure have significant effects on the spalling failure.The spalling strength is approximately(0.3–0.8)UCS,where UCS is the uniaxial compressive strength of the cylindrical rock sample with a diameter of around 50 mm.The spalling strength increases first and then decreases with increasing intermediate principal stress.Moreover,an empirical spalling strength criterion and a numerical method of spalling failure are proposed.This numerical method can not only simulate the spalling failure zone formed by tangential compressive stress concentration after excavation under different intermediate principal stresses,but also successfully simulate the failure transition from tensile mode to shear mode associated with confinement change in deep hard rock caverns.Furthermore,an acoustic emission-based early warning method using neural network is proposed to predict the spalling failure.Finally,a technical roadmap for preventing and controlling spalling failure of deep hard rock caverns is presented after summarizing the successful experiences in a typical engineering case.展开更多
Purpose:To evaluate the feasibility and efficacy of a transmesenteric vein extrahepatic portosystemic shunt(TmEPS)for the treatment of cavernous transformation of the portal vein(CTPV).Materials and methods:The clinic...Purpose:To evaluate the feasibility and efficacy of a transmesenteric vein extrahepatic portosystemic shunt(TmEPS)for the treatment of cavernous transformation of the portal vein(CTPV).Materials and methods:The clinical data of 20 patients with CTPV who underwent TmEPS between December 2020and January 2022 at Henan Provincial People’s Hospital were retrospectively collected.The superior mesenteric vein(SMV)trunk was patent or partially occluded in these patients.An extrahepatic portosystemic shunt between the inferior vena cava and the SMV was established using a stent graft through an infraumbilical median longitudinal mini-laparotomy.The technical success,efficacy,and complication rates were evaluated,and the preand postoperative SMV pressures were compared.Patients’clinical outcomes and shunt patency were assessed.Results:TmEPS was successfully performed in 20 patients.The initial puncture success rate of the balloon-assisted puncture technique is 95%.The mean SMV pressure decreased from 29.1±2.9 mmHg to 15.6±3.3 mmHg(p<0.001).All symptoms of portal hypertension resolved.No fatal procedural complications occurred.During the follow-up period,hepatic encephalopathy occurred in two patients.The remaining patients remained asymptomatic.All shunts were patent.Conclusions:TmEPS is a feasible,safe,and effective treatment option for patients with CTPV.展开更多
Undergroundgas storage caverns aremonitoredfor environmental safety in termsof equipmentandpotential emissions,particularly methane emissions from the underground and above-ground parts of the storage facility.Periodi...Undergroundgas storage caverns aremonitoredfor environmental safety in termsof equipmentandpotential emissions,particularly methane emissions from the underground and above-ground parts of the storage facility.Periodical measurements of land surface deformations and costly echometric measurements of convergence of individual storage facilities are carried out.The aims of environmental monitoring are:(1)to eliminate potential hazards in the shortest time,(2)assess the overall impact of intensive operation of storage facilities on the environment,(3)developmonitoringmethods relevant to environmental protection,and(4)take actions in case of failure.The paper presents a solution to the problem of determination of the convergence of underground caverns in a salt rock mass based on the results of land surface subsidence measurements carried out using the Gauss-Markov equalization algorithm.Themethod makes it possible for ongoing control of cavern volume convergence after each subsidence measurement on the ground surface and determining the actual impact of the use frequency(injection-mediumconsumption)on the convergence in time.The presentedmethodology is universal and verified on caverns located in a salt rockmass.The Gauss-Markov inversion model is the first used in this area,hence its application is significant.展开更多
BACKGROUND Primary abdominal and retroperitoneal cavernous hemangioma is a vascular tumor and rarely seen in the clinic.Due to the lack of specific imaging features,retroperitoneal cavernous hemangioma cannot be diagn...BACKGROUND Primary abdominal and retroperitoneal cavernous hemangioma is a vascular tumor and rarely seen in the clinic.Due to the lack of specific imaging features,retroperitoneal cavernous hemangioma cannot be diagnosed accurately.Some symptoms may develop with the enlargement of lesion volume or the occurrence of complications such as rupture or oppression.We report here a special case who was admitted with chronic abdominal pain.Admission examination suggested a retroperitoneal lymphatic duct cyst.Laparoscopic resection of the retroperitoneal mass was performed,and histological examination confirmed retroperitoneal cavernous hemangioma.CASE SUMMARY The patient was a 43-year-old Tibetan woman with intermittent left lower abdominal pain and discomfort 3 years ago.Ultrasonography revealed a cystic mass in the retroperitoneum with clear boundaries,internal septa,and no blood flow signal.Computed tomography(CT)and magnetic resonance imaging(MRI)showed an irregular space-occupying mass in the retroperitoneum,and retroperitoneal lymphatic cyst was considered.Plain CT scanning showed multiple cystlike hypo-intense shadows in the retroperitoneum,partially fused into a mass,and no obvious enhancement was found on enhanced scanning.MRI showed multiple irregular clump-like long T1 and long T2 signal shadows above the pancreas,within which linear short T2 signal shadows were seen.Diffusionweighted imaging sequence showed hypo-signal shadows,without obvious enhancement on enhanced scanning.Ultrasound,CT,and MRI all suggested the possibility of retroperitoneal lymphatic cyst.However,the patient was finally diagnosed with retroperitoneal cavernous hemangioma by pathological examination.CONCLUSION Retroperitoneal cavernous hemangioma is a benign lesion,and it is difficult to make a diagnosis preoperatively.Surgical resection may be the only treatment,which not only allows histopathological confirmation as a diagnostic purpose and excludes any risk of malignancy,but also avoids invasion of adjacent tissues,oppression,and other complications as a therapeutic goal.展开更多
The storage of hydrogen gas in lined rock caverns(LRCs)may enable the implementation of the firstlarge-scale fossil-free steelmaking process in Sweden,but filling such storage causes joints in the rockmass to open,con...The storage of hydrogen gas in lined rock caverns(LRCs)may enable the implementation of the firstlarge-scale fossil-free steelmaking process in Sweden,but filling such storage causes joints in the rockmass to open,concentrating strains in the lining.The structural interaction between the LRC componentsmust be able to reduce the strain concentration in the sealing steel lining;however,this interaction iscomplex and difficult to predict with analytical methods.In this paper,the strain concentration in LRCsfrom the opening of rock joints is studied using finite element(FE)analyses,where the large-and small-scale deformation behaviors of the LRC are coupled.The model also includes concrete crack initiation anddevelopment with increasing gas pressure and rock joint width.The interaction between the jointed rockmass and the reinforced concrete,the sliding layer,and the steel lining is demonstrated.The results showthat the rock mass quality and the spacing of the rock joints have the greatest influence on the straindistributions in the steel lining.The largest effect of rock joints on the maximum strains in the steellining was observed for geological conditions of“good”quality rock masses.展开更多
BACKGROUND High flow priapism(HFP)is a rare type of priapism.Perineal trauma is the most common cause of HFP.Trauma-induced penile artery injury may lead to an arterial-cavernosal fistula,whereas persistent irregular ...BACKGROUND High flow priapism(HFP)is a rare type of priapism.Perineal trauma is the most common cause of HFP.Trauma-induced penile artery injury may lead to an arterial-cavernosal fistula,whereas persistent irregular arterial blood flow entering the corpora cavernosum can cause a persistent penile erection.The routine treatment of HFP focuses on addressing the abnormal penile erectile status and avoiding post-treatment erectile dysfunction.Interventional embolization is an important therapeutic modality for HFP,and bilateral embolization therapy is currently the most commonly used technique for patients with bilateral cavernous artery fistulas;however,unilateral embolization therapy has yet to be reported.CASE SUMMARY Herein,we report of the case of a 26-year-old Chinese male who presented with a persistent abnormal erection for 12 h after perineal impact injury.Medical history,cavernous arterial blood gas analysis and radiological examinations led to a diagnosis of HFP caused by bilateral cavernous artery fistulas.We performed routine conservative treatment(compression therapy and ice application)for the patient after admission;however,10 d later,his symptoms had not been relieved.After completion of the preoperative workup,right(severe side)selective perineal artery embolization was performed;the left cavernous artery fistula was left untreated.After postoperative continuation of conservative treatment for 72 h,the patient experienced complete penile thinning.The patient had no symptoms of erectile dysfunction over a follow-up period of 12 mo.CONCLUSION Compared with bilateral cavernous artery fistula embolization,we believe that unilateral cavernous artery fistula embolization can achieve positive clinical efficacy and reduce the risk of postoperative erectile dysfunction secondary to penile ischemia.展开更多
BACKGROUND Pancreatic cavernous hemangioma(pCH)is a rare type of benign vascular tumor.Making the right diagnosis is challenging due to low clinical suspicion and the lack of existing cross-sectional imaging tools to ...BACKGROUND Pancreatic cavernous hemangioma(pCH)is a rare type of benign vascular tumor.Making the right diagnosis is challenging due to low clinical suspicion and the lack of existing cross-sectional imaging tools to distinguish it from other pancreatic lesions.CASE SUMMARY We describe a male patient,age 18,who presented with a pCH.Computed tomography,magnetic resonance imaging,and ultrasound showed cystic space in the tail of the pancreas.A dark spot sign on the T2 weighted image sequence was observed.Clinically,a mucinous cystic neoplasm with hemorrhage was suspected preoperatively by combining imaging,and the operative indication was clear.The patient underwent a distal pancreatic tumor resection under laparoscopic control.Immunohistochemical staining for CD31 and CD34 was positive;D2-40 was positive in interstitial lymphatic vessels and negative in vascular epithelial cells;and calcium-binding protein was negative.The results support the diagnosis of pCH combined with chronic intracapsular spontaneous hemorrhage.No complications or recurrences were observed during the follow-up period.CONCLUSION Chronic spontaneous hemorrhage may occur in pCH,which may greatly influence the accuracy of diagnosis using imaging modalities.Surgical resection for uncertain pCH seems reasonable with a good outcome.展开更多
文摘Cerebral cavernous malformations are a rare and congenital vascular malformation that can present as a challenge in neurosurgical management. The term “giant cerebral cavernous malformations” still does not have a clear definition in the literature, with a wide variety of results. It is known, however, that there is an association between the size of the cavernoma and postoperative sequelae, especially in those with a size greater than 3 cm in its largest diameter. We present a case report of resection of a giant brain cavernoma measuring approximately 8 cm in its largest diameter, emphasizing on clinical presentation, diagnoses and postoperative evolution. Additionally, we performed a comprehensive review of the existing literature on the subject, addressing the epidemiology, pathophysiology, diagnostic methods, treatment options, and prognosis associated with this condition.
文摘BACKGROUND Direct carotid cavernous fistulas(CCFs)are typically the result of a severe traumatic brain injury.High-flow arteriovenous shunts secondary to rupture of an intracavernous aneurysm,resulting in direct CCFs,are rare.The use of a pipeline embolization device in conjunction with coils and Onyx glue for treatment of direct high-flow CCF resulting from ruptured cavernous carotid artery aneurysm in a clinical setting is not well documented.CASE SUMMARY A 58-year-old woman presented to our department with symptoms of blepharoptosis and intracranial bruits for 1 wk.During physical examination,there was right eye exophthalmos and ocular motor palsy.The rest of the neurological examination was clear.Notably,the patient had no history of head injury.The patient was treated with a pipeline embolization device in the ipsilateral internal carotid artery across the fistula.Coils and Onyx were placed through the femoral venous route,followed by placement of the pipeline embolization device with assistance from a balloon-coiling technique.No intraoperative or perioperative complications occurred.Preoperative symptoms of bulbar hyperemia and bruits subsided immediately after the operation.CONCLUSION Pipeline embolization device in conjunction with coiling and Onyx may be a safe and effective approach for direct CCFs.
文摘Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.
基金supported by the National Natural Science Foundation of China(52074046,52122403,51834003,and 52274073)the Graduate Research and Innovation Foundation of Chongqing(CYB22023)+2 种基金the Chongqing Talents Plan for Young Talents(cstc2022ycjh-bgzxm0035)Hunan Institute of Engineering(21RC025 and XJ2005)Hunan Province Education Department(21B0664).
文摘Underground salt cavern CO_(2) storage(SCCS)offers the dual benefits of enabling extensive CO_(2) storage and facilitating the utilization of CO_(2) resources while contributing the regulation of the carbon market.Its economic and operational advantages over traditional carbon capture,utilization,and storage(CCUS)projects make SCCS a more cost-effective and flexible option.Despite the widespread use of salt caverns for storing various substances,differences exist between SCCS and traditional salt cavern energy storage in terms of gas-tightness,carbon injection,brine extraction control,long-term carbon storage stability,and site selection criteria.These distinctions stem from the unique phase change characteristics of CO_(2) and the application scenarios of SCCS.Therefore,targeted and forward-looking scientific research on SCCS is imperative.This paper introduces the implementation principles and application scenarios of SCCS,emphasizing its connections with carbon emissions,carbon utilization,and renewable energy peak shaving.It delves into the operational characteristics and economic advantages of SCCS compared with other CCUS methods,and addresses associated scientific challenges.In this paper,we establish a pressure equation for carbon injection and brine extraction,that considers the phase change characteristics of CO_(2),and we analyze the pressure during carbon injection.By comparing the viscosities of CO_(2) and other gases,SCCS’s excellent sealing performance is demonstrated.Building on this,we develop a long-term stability evaluation model and associated indices,which analyze the impact of the injection speed and minimum operating pressure on stability.Field countermeasures to ensure stability are proposed.Site selection criteria for SCCS are established,preliminary salt mine sites suitable for SCCS are identified in China,and an initial estimate of achievable carbon storage scale in China is made at over 51.8-77.7 million tons,utilizing only 20%-30%volume of abandoned salt caverns.This paper addresses key scientific and engineering challenges facing SCCS and determines crucial technical parameters,such as the operating pressure,burial depth,and storage scale,and it offers essential guidance for implementing SCCS projects in China.
基金Project(2023YFC2907204)supported by the National Key Research and Development Program of ChinaProject(52325905)supported by the National Natural Science Foundation of ChinaProject(DJ-HXGG-2023-16)supported by the Key Technology Research Projects of Power China。
文摘Underground energy and resource development,deep underground energy storage and other projects involve the global stability of multiple interconnected cavern groups under internal and external dynamic disturbances.An evaluation method of the global stability coefficient of underground caverns based on static overload and dynamic overload was proposed.Firstly,the global failure criterion for caverns was defined based on its band connection of plastic-strain between multi-caverns.Then,overloading calculation of the boundary geostress and seismic intensity on the caverns model was carried out,and the critical unstable state of multi-caverns can be identified,if the plastic-strain band appeared between caverns during these overloading processes.Thus,the global stability coefficient for the multi-caverns under static loading and earthquake was obtained based on the corresponding overloading coefficient.Practical analysis for the Yingliangbao(YLB)hydraulic caverns indicated that this method can not only effectively obtain the global stability coefficient of caverns under static and dynamic earthquake conditions,but also identify the caverns’high-risk zone of local instability through localized plastic strain of surrounding rock.This study can provide some reference for the layout design and seismic optimization of underground cavern group.
基金the financial support from the Natural Science Foundation of China (Nos.52179118,52209151 and 42307238)the Science and Technology Project of Jiangsu Provincial Department of Science and Technology-Carbon Emissions Peak and Carbon Neutrality Science and Technology Innovation Specia Fund Project (No.BK20220025)+3 种基金the Excellent Postdoctoral Program of Jiangsu Province (No.2023ZB602)the China Postdoctora Science Foundation (Nos.2023M733773 and 2023M733772)Xuzhou City Science and Technology Innovation Special Basic Research Plan (KC23045)State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,China University of Mining&Technology (No SKLGDUEK1916)。
文摘Underground hydrogen storage(UHS)and compressed air energy storage(CAES)are two viable largescale energy storage technologies for mitigating the intermittency of wind and solar power.Therefore,it is meaningful to compare the properties of hydrogen and air with typical thermodynamic storage processes.This study employs a multi-physical coupling model to compare the operations of CAES and UHS,integrating gas thermodynamics within caverns,thermal conduction,and mechanical deformation around rock caverns.Gas thermodynamic responses are validated using additional simulations and the field test data.Temperature and pressure variations of air and hydrogen within rock caverns exhibit similarities under both adiabatic and diabatic simulation modes.Hydrogen reaches higher temperature and pressure following gas charging stage compared to air,and the ideal gas assumption may lead to overestimation of gas temperature and pressure.Unlike steel lining of CAES,the sealing layer(fibre-reinforced plastic FRP)in UHS is prone to deformation but can effectively mitigates stress in the sealing layer.In CAES,the first principal stress on the surface of the sealing layer and concrete lining is tensile stress,whereas UHS exhibits compressive stress in the same areas.Our present research can provide references for the selection of energy storage methods.
基金supported by the Henan Institute for Chinese Development Strategy of Engineering&Technology(Grant No.2022HENZDA02)the Since&Technology Department of Sichuan Province Project(Grant No.2021YFH0010)the High‐End Foreign Experts Program of the Yunnan Revitalization Talents Support Plan of Yunnan Province.
文摘Large‐scale underground hydrogen storage(UHS)provides a promising method for increasing the role of hydrogen in the process of carbon neutrality and energy transition.Of all the existing storage deposits,salt caverns are recognized as ideal sites for pure hydrogen storage.Evaluation and optimization of site selection for hydrogen storage facilities in salt caverns have become significant issues.In this article,the software CiteSpace is used to analyze and filter hot topics in published research.Based on a detailed classification and analysis,a“four‐factor”model for the site selection of salt cavern hydrogen storage is proposed,encompassing the dynamic demands of hydrogen energy,geological,hydrological,and ground factors of salt mines.Subsequently,20 basic indicators for comprehensive suitability grading of the target site were screened using the analytic hierarchy process and expert survey methods were adopted,which provided a preliminary site selection system for salt cavern hydrogen storage.Ultimately,the developed system was applied for the evaluation of salt cavern hydrogen storage sites in the salt mines of Pingdingshan City,Henan Province,thereby confirming its rationality and effectiveness.This research provides a feasible method and theoretical basis for the site selection of UHS in salt caverns in China.
基金Supported by Natural Science Foundation of Zhejiang Province,No.LY20H030010Medical Health Science and Technology Project of Zhejiang Provincial Health Commission,No.2019-KY1-001-181.
文摘BACKGROUND Colorectal cavernous hemangioma is a rare vascular malformation resulting in recurrent lower gastrointestinal hemorrhage,and can be misinterpreted as colitis.Surgical resection is currently the mainstay of treatment,with an emphasis on sphincter preservation.CASE SUMMARY We present details of two young patients with a history of persistent hematochezia diagnosed with colorectal cavernous hemangioma by endoscopic ultrasound(EUS).Cavernous hemangioma was relieved by several EUS-guided lauromacrogol injections and the patients achieved favorable clinical prognosis.CONCLUSION Multiple sequential EUS-guided injections of lauromacrogol is a safe,effective,cost-efficient,and minimally invasive alternative for colorectal cavernous hemangioma.
基金Supported by The Fong Shu Fook Tong and Fong Yun Wah Foundations,No.14X30127.
文摘BACKGROUND Patients with giant intracranial aneurysms(GIAs)are at a high risk of rupture,morbidity,and mortality even after surgical or endovascular treatment.We described a case of a spontaneously occluded GIA secondary to gradual growth of the GIA,continuously progressed aneurysmal thrombosis,complete aneurysmal calcification and complete occlusion of the parent artery-the right internal carotid artery(RICA).CASE SUMMARY A 72-year-old female patient complained of sudden pain in her right eye upon admission to our hospital.She had been diagnosed with a GIA[30 mm(axial)×38 mm(coronal)×28 mm(sagittal)]containing an aneurysmal thrombus located in the cavernous sinus segment of RICA diagnosed by magnetic resonance imaging(MRI),enhanced MRI,and magnetic resonance angiography more than 14 years ago.Later,with slow growth of the cavernous carotid GIA,aneurysmal thrombosis progressed continuously,spontaneous occlusion of the RICA,complete aneurysmal calcification,and occlusion of the GIA occurred gradually.She had no history of subarachnoid hemorrhage but missed the chance for endovascular therapy at an early stage.As a result,she was left with severe permanent sequelae from the injuries to the right cranial nerves Ⅱ,Ⅲ,Ⅳ,V1/V2,and Ⅴ.CONCLUSION The risk of rupture of the cavernous carotid GIAs was relatively low and possibly further be reduced by the stasis flow and spontaneous occlusion of the parent artery internal carotid artery(ICA)induced by the mass effect of the cavernous carotid GIAs and the extremely rare aneurysmal calcification.However,nowadays,it is advisable to recommend early endovascular treatment for the cavernous carotid GIAs to prevent injuries to the surrounding intracranial nerves and occlusion of the ICA,mainly caused by the mass effect of the cavernous carotid GIAs.
文摘BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in adults.As a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis.However,lymphangiomas can give rise to complications such as abdominal pain,bleeding,volvulus,and intussusception.Here,we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male adult.CASE SUMMARY A 66-year-old man presented with intermittent melena,fatigue and refractory anemia nine months prior.Esophagogastroduodenoscopy and colonoscopy were performed many times and revealed no apparent bleeding.Conservative management,including transfusion,hemostasis,gastric acid secretion inhibition and symptomatic treatment,was performed,but the lesions tended to recur shortly after surgery.Ultimately,the patient underwent capsule endoscopy,which revealed a more than 10 cm lesion accompanied by active bleeding.After singleballoon enteroscopy and biopsy,a diagnosis of jejunal cavernous lymphangioma was confirmed,and the patient underwent surgical resection.No complications or recurrences were observed postoperatively.CONCLUSION Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal bleeding.Capsule endoscopy and single-balloon enteroscopy can facilitate diagnosis.Surgical resection is an effective management method.
文摘Objective:To investigate the computed tomography(CT)and magnetic resonance imaging(MRI)features of cavernous hemangioma malformation(CHM)to enhance diagnostic accuracy.Methods:The CT and MRI findings and clinical information of 23 patients with CHM were retrospectively analyzed.Results:CT examinations were conducted in 7 cases,while MRI was utilized in 23 cases.Additionally,SWI was employed in 5 cases and enhanced imaging techniques were applied in 14 cases.Among the observed lesions,20 cases presented with a singular lesion,whereas 3 cases exhibited multiple lesions.The lesions were located in 8 frontal lobes,6 cerebellums,2 brainstems,6 temporal lobes,1 basal ganglia,3 parieto-occipital lobes,and 2 thalamus regions.The nodules appeared as quasi-circular lesions with clear or well-defined boundaries.They presented as isodense lesions on CT scans,with one lesion showing peritumoral edema.On MRI,T1-weighted imaging(T1WI)demonstrated isointense signals,while T2-weighted imaging(T2WI)showed isointense and hyperintense signals.Additionally,10 lesions exhibited a low signal ring on T2WI.Diffusion-weighted imaging(DWI)revealed nodular or isointense low signals,while susceptibility-weighted imaging(SWI)displayed enlarged areas of low signal.Fourteen lesions underwent contrast-enhanced scanning,with 2 lesions showing no obvious enhancement,1 lesion demonstrating mild to moderate enhancement,and 11 lesions exhibiting significant enhancement.Notably,6 of these enhanced lesions were surrounded by small blood vessels.Conclusion:Cavernous hemangioma malformation is more commonly found in individual cases.CT alone lacks specificity,making it prone to misdiagnosis.A more comprehensive evaluation of cavernous hemangioma malformation can be achieved through a combination of MRI,DWI,SWI,and enhanced examination,providing valuable references for clinical assessment.
基金This work has been conducted as part of the HYBRIT research project RP-1.This research was financially supported by the Swedish Energy Agency(Grant No.42684e2).
文摘The storage of hydrogen gas in underground lined rock caverns(LRCs)enables the implementation of the first fossil-free steelmaking process to meet the large demand for crude steel.Predicting the response of rock mass is important to ensure that gas leakage due to rupture of the steel lining does not occur.Analytical and numerical models can be used to estimate the rock mass response to high internal pressure;however,the fitness of these models under different in situ stress conditions and cavern shapes has not been studied.In this paper,the suitability of analytical and numerical models to estimate the maximum cavern wall tangential strain under high internal pressure is studied.The analytical model is derived in detail and finite element(FE)models considering both two-dimensional(2D)and three-dimensional(3D)geometries are presented.These models are verified with field measurements from the LRC in Skallen,southwestern Sweden.The analytical model is inexpensive to implement and gives good results for isotropic in situ stress conditions and large cavern heights.For the case of anisotropic horizontal in situ stresses,as the conditions in Skallen,the 3D FE model is the best approach.
基金supported by the National Natural Science Foundation of China (22078030, U1802255)National Key Research and Development Project (2019YFC1905802)+1 种基金Key Project of Independent Research Project of State Key Laboratory of Coal Mine Disaster Dynamics and Control (2011DA105287-zd201902)Three Gorges Laboratory Open Fund of Hubei Province (SK211009, SK215001)。
文摘The hydrodynamic performance of three mixers single shaft central mixer(SSC), single shaft off-centred mixer(SSO), dual shaft off-centred mixer(DSO), was investigated in the mixing of yield-pseudoplastic fluids(xanthan gum solutions) in the laminar regime. To explore and determine the efficiency of three mixers, both numerical and experimental approaches were adopted. The fluid rheology was described by the Herschel–Bulkley rheological model. Computational fluid dynamics was employed to simulate the apparent viscosity distribution, mixing time, and the flow pattern inside the stirred tank. The developed model was validated through experimentally measured torque. The influence mechanism of the rotational speed and fluid rheology on the cavern evolution was explored deeply. The performances of three mixers in this work were compared at the constant power input and fluid rheology with respect to the flow pattern, mixing time, and mixing efficiency. The results verify that the faster the rotating speed, the greater influence of the fluid rheology on the cavern evolution, and the more uniform apparent viscosity distribution. Moreover, the mixing time decreases continuously as the increasing power consumption per unit volume, and the dimensionless mixing time of DSO mixer was nearly 42.8% and 6.1% shorter than that of SSC and SCO mixer at the same Reynolds number, respectively. According to the mixing efficiency criteria, these data also revealed that DSO was more efficient than SSC and SSO.
基金The authors greatly gratefully acknowledge the financial support from the National Natural Science Foundation of China(Grant Nos.52169021 and 51869003)the Interdisciplinary Scientific Research Foundation of Guangxi University,China(Grant No.2022JCA004).
文摘Spalling is a typical brittle failure phenomenon of hard rock in deep caverns under high geostress.In this study,key issues are systematically studied concerning the spalling failure of deep hard rock caverns.First,the prismatic rock specimens with small thicknesses(i.e.width×thickness×height:20 mm×50 mm×100 mm)are employed in our tests which not only successfully simulate the spalling failure of hard rock in the laboratory but also obtain a reasonable spalling strength similar to that of the rock mass.Then,a series of spalling experiments is carried out to investigate the mechanism of spalling failure of deep hard rock caverns.Our results show that the intermediate principal stress,weak dynamic disturbances,and rock microstructure have significant effects on the spalling failure.The spalling strength is approximately(0.3–0.8)UCS,where UCS is the uniaxial compressive strength of the cylindrical rock sample with a diameter of around 50 mm.The spalling strength increases first and then decreases with increasing intermediate principal stress.Moreover,an empirical spalling strength criterion and a numerical method of spalling failure are proposed.This numerical method can not only simulate the spalling failure zone formed by tangential compressive stress concentration after excavation under different intermediate principal stresses,but also successfully simulate the failure transition from tensile mode to shear mode associated with confinement change in deep hard rock caverns.Furthermore,an acoustic emission-based early warning method using neural network is proposed to predict the spalling failure.Finally,a technical roadmap for preventing and controlling spalling failure of deep hard rock caverns is presented after summarizing the successful experiences in a typical engineering case.
基金supported by the Henan medical science and technology research projects(222102310014)
文摘Purpose:To evaluate the feasibility and efficacy of a transmesenteric vein extrahepatic portosystemic shunt(TmEPS)for the treatment of cavernous transformation of the portal vein(CTPV).Materials and methods:The clinical data of 20 patients with CTPV who underwent TmEPS between December 2020and January 2022 at Henan Provincial People’s Hospital were retrospectively collected.The superior mesenteric vein(SMV)trunk was patent or partially occluded in these patients.An extrahepatic portosystemic shunt between the inferior vena cava and the SMV was established using a stent graft through an infraumbilical median longitudinal mini-laparotomy.The technical success,efficacy,and complication rates were evaluated,and the preand postoperative SMV pressures were compared.Patients’clinical outcomes and shunt patency were assessed.Results:TmEPS was successfully performed in 20 patients.The initial puncture success rate of the balloon-assisted puncture technique is 95%.The mean SMV pressure decreased from 29.1±2.9 mmHg to 15.6±3.3 mmHg(p<0.001).All symptoms of portal hypertension resolved.No fatal procedural complications occurred.During the follow-up period,hepatic encephalopathy occurred in two patients.The remaining patients remained asymptomatic.All shunts were patent.Conclusions:TmEPS is a feasible,safe,and effective treatment option for patients with CTPV.
文摘Undergroundgas storage caverns aremonitoredfor environmental safety in termsof equipmentandpotential emissions,particularly methane emissions from the underground and above-ground parts of the storage facility.Periodical measurements of land surface deformations and costly echometric measurements of convergence of individual storage facilities are carried out.The aims of environmental monitoring are:(1)to eliminate potential hazards in the shortest time,(2)assess the overall impact of intensive operation of storage facilities on the environment,(3)developmonitoringmethods relevant to environmental protection,and(4)take actions in case of failure.The paper presents a solution to the problem of determination of the convergence of underground caverns in a salt rock mass based on the results of land surface subsidence measurements carried out using the Gauss-Markov equalization algorithm.Themethod makes it possible for ongoing control of cavern volume convergence after each subsidence measurement on the ground surface and determining the actual impact of the use frequency(injection-mediumconsumption)on the convergence in time.The presentedmethodology is universal and verified on caverns located in a salt rockmass.The Gauss-Markov inversion model is the first used in this area,hence its application is significant.
基金Supported by Health Commission of Qinghai Province,No.2020-wjzdx-28.
文摘BACKGROUND Primary abdominal and retroperitoneal cavernous hemangioma is a vascular tumor and rarely seen in the clinic.Due to the lack of specific imaging features,retroperitoneal cavernous hemangioma cannot be diagnosed accurately.Some symptoms may develop with the enlargement of lesion volume or the occurrence of complications such as rupture or oppression.We report here a special case who was admitted with chronic abdominal pain.Admission examination suggested a retroperitoneal lymphatic duct cyst.Laparoscopic resection of the retroperitoneal mass was performed,and histological examination confirmed retroperitoneal cavernous hemangioma.CASE SUMMARY The patient was a 43-year-old Tibetan woman with intermittent left lower abdominal pain and discomfort 3 years ago.Ultrasonography revealed a cystic mass in the retroperitoneum with clear boundaries,internal septa,and no blood flow signal.Computed tomography(CT)and magnetic resonance imaging(MRI)showed an irregular space-occupying mass in the retroperitoneum,and retroperitoneal lymphatic cyst was considered.Plain CT scanning showed multiple cystlike hypo-intense shadows in the retroperitoneum,partially fused into a mass,and no obvious enhancement was found on enhanced scanning.MRI showed multiple irregular clump-like long T1 and long T2 signal shadows above the pancreas,within which linear short T2 signal shadows were seen.Diffusionweighted imaging sequence showed hypo-signal shadows,without obvious enhancement on enhanced scanning.Ultrasound,CT,and MRI all suggested the possibility of retroperitoneal lymphatic cyst.However,the patient was finally diagnosed with retroperitoneal cavernous hemangioma by pathological examination.CONCLUSION Retroperitoneal cavernous hemangioma is a benign lesion,and it is difficult to make a diagnosis preoperatively.Surgical resection may be the only treatment,which not only allows histopathological confirmation as a diagnostic purpose and excludes any risk of malignancy,but also avoids invasion of adjacent tissues,oppression,and other complications as a therapeutic goal.
基金supported by the Swedish Energy Agency(Grant Nos.42684-2,P2022-00209).
文摘The storage of hydrogen gas in lined rock caverns(LRCs)may enable the implementation of the firstlarge-scale fossil-free steelmaking process in Sweden,but filling such storage causes joints in the rockmass to open,concentrating strains in the lining.The structural interaction between the LRC componentsmust be able to reduce the strain concentration in the sealing steel lining;however,this interaction iscomplex and difficult to predict with analytical methods.In this paper,the strain concentration in LRCsfrom the opening of rock joints is studied using finite element(FE)analyses,where the large-and small-scale deformation behaviors of the LRC are coupled.The model also includes concrete crack initiation anddevelopment with increasing gas pressure and rock joint width.The interaction between the jointed rockmass and the reinforced concrete,the sliding layer,and the steel lining is demonstrated.The results showthat the rock mass quality and the spacing of the rock joints have the greatest influence on the straindistributions in the steel lining.The largest effect of rock joints on the maximum strains in the steellining was observed for geological conditions of“good”quality rock masses.
基金Supported by Foundation of the General Hospital of Western Command,No.2021-XZYG-C04。
文摘BACKGROUND High flow priapism(HFP)is a rare type of priapism.Perineal trauma is the most common cause of HFP.Trauma-induced penile artery injury may lead to an arterial-cavernosal fistula,whereas persistent irregular arterial blood flow entering the corpora cavernosum can cause a persistent penile erection.The routine treatment of HFP focuses on addressing the abnormal penile erectile status and avoiding post-treatment erectile dysfunction.Interventional embolization is an important therapeutic modality for HFP,and bilateral embolization therapy is currently the most commonly used technique for patients with bilateral cavernous artery fistulas;however,unilateral embolization therapy has yet to be reported.CASE SUMMARY Herein,we report of the case of a 26-year-old Chinese male who presented with a persistent abnormal erection for 12 h after perineal impact injury.Medical history,cavernous arterial blood gas analysis and radiological examinations led to a diagnosis of HFP caused by bilateral cavernous artery fistulas.We performed routine conservative treatment(compression therapy and ice application)for the patient after admission;however,10 d later,his symptoms had not been relieved.After completion of the preoperative workup,right(severe side)selective perineal artery embolization was performed;the left cavernous artery fistula was left untreated.After postoperative continuation of conservative treatment for 72 h,the patient experienced complete penile thinning.The patient had no symptoms of erectile dysfunction over a follow-up period of 12 mo.CONCLUSION Compared with bilateral cavernous artery fistula embolization,we believe that unilateral cavernous artery fistula embolization can achieve positive clinical efficacy and reduce the risk of postoperative erectile dysfunction secondary to penile ischemia.
文摘BACKGROUND Pancreatic cavernous hemangioma(pCH)is a rare type of benign vascular tumor.Making the right diagnosis is challenging due to low clinical suspicion and the lack of existing cross-sectional imaging tools to distinguish it from other pancreatic lesions.CASE SUMMARY We describe a male patient,age 18,who presented with a pCH.Computed tomography,magnetic resonance imaging,and ultrasound showed cystic space in the tail of the pancreas.A dark spot sign on the T2 weighted image sequence was observed.Clinically,a mucinous cystic neoplasm with hemorrhage was suspected preoperatively by combining imaging,and the operative indication was clear.The patient underwent a distal pancreatic tumor resection under laparoscopic control.Immunohistochemical staining for CD31 and CD34 was positive;D2-40 was positive in interstitial lymphatic vessels and negative in vascular epithelial cells;and calcium-binding protein was negative.The results support the diagnosis of pCH combined with chronic intracapsular spontaneous hemorrhage.No complications or recurrences were observed during the follow-up period.CONCLUSION Chronic spontaneous hemorrhage may occur in pCH,which may greatly influence the accuracy of diagnosis using imaging modalities.Surgical resection for uncertain pCH seems reasonable with a good outcome.