BACKGROUND Infarction of the conus medullaris is a rare form of spinal cord infarction.The first symptom is usually acute non-characteristic lumbar pain,followed by lower limb pain,saddle numbness,fecal incontinence,a...BACKGROUND Infarction of the conus medullaris is a rare form of spinal cord infarction.The first symptom is usually acute non-characteristic lumbar pain,followed by lower limb pain,saddle numbness,fecal incontinence,and sexual dysfunction.Spontaneous conus infarction with"snake-eye appearance"on magnetic resonance imaging has rarely been reported.CASE SUMMARY We report a 79-year-old male patient with spontaneous conus infarction who had acute lower extremity pain and dysuria as the first symptoms.He did not have any recent history of aortic surgery and trauma.Magnetic resonance imaging revealed a rare"snake-eye appearance."In addition,we reviewed the literature on 23 similar cases and summarized the clinical features and magnetic resonance manifestations of common diseases related to the"snake-eye sign"to explore the etiology,imaging findings,and prognosis of spontaneous conus infarction.CONCLUSION We conclude that acute onset of conus medullaris syndrome combined with"snake-eye appearance"should be strongly suspected as conus medullaris infarction caused by anterior spinal artery ischemia.This special imaging manifestation is helpful in the early diagnosis and treatment of conus infarction.展开更多
In this study,an experimental setup is designed and built to investigate the feasibility and performance of the proposed dual-mode cascade refrigeration cycle.The apparatus can be operated in two modes:dual-stage mode...In this study,an experimental setup is designed and built to investigate the feasibility and performance of the proposed dual-mode cascade refrigeration cycle.The apparatus can be operated in two modes:dual-stage mode and single-stage mode such that the low temperature cycle(LTC) can be operated together with the high temperature cycle(HTC) or can run independently.Experimental results validate the feasibility of independent operation of LTC.The performance of the independent operation of LTC mode is theoretically investigated using experimental data as bases.Detailed suggestions are made for the improvement of the coefficient of performance(COP) of the experimental system.Theoretically,high COP of the cycle provides excellent application for the presented refrigeration cycle.展开更多
文摘BACKGROUND Infarction of the conus medullaris is a rare form of spinal cord infarction.The first symptom is usually acute non-characteristic lumbar pain,followed by lower limb pain,saddle numbness,fecal incontinence,and sexual dysfunction.Spontaneous conus infarction with"snake-eye appearance"on magnetic resonance imaging has rarely been reported.CASE SUMMARY We report a 79-year-old male patient with spontaneous conus infarction who had acute lower extremity pain and dysuria as the first symptoms.He did not have any recent history of aortic surgery and trauma.Magnetic resonance imaging revealed a rare"snake-eye appearance."In addition,we reviewed the literature on 23 similar cases and summarized the clinical features and magnetic resonance manifestations of common diseases related to the"snake-eye sign"to explore the etiology,imaging findings,and prognosis of spontaneous conus infarction.CONCLUSION We conclude that acute onset of conus medullaris syndrome combined with"snake-eye appearance"should be strongly suspected as conus medullaris infarction caused by anterior spinal artery ischemia.This special imaging manifestation is helpful in the early diagnosis and treatment of conus infarction.
基金supported by the National Natural Science Foundation of China (No. 50976082)the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20090201110006)the State Key Laboratory of Multiphase Flow of Xi’an Jiaotong University,China
文摘In this study,an experimental setup is designed and built to investigate the feasibility and performance of the proposed dual-mode cascade refrigeration cycle.The apparatus can be operated in two modes:dual-stage mode and single-stage mode such that the low temperature cycle(LTC) can be operated together with the high temperature cycle(HTC) or can run independently.Experimental results validate the feasibility of independent operation of LTC.The performance of the independent operation of LTC mode is theoretically investigated using experimental data as bases.Detailed suggestions are made for the improvement of the coefficient of performance(COP) of the experimental system.Theoretically,high COP of the cycle provides excellent application for the presented refrigeration cycle.