Non-invasive Doppler ultrasonographic study of cerebral arteries [transcranial Doppler(TCD)] has been extensively applied on both outpatient and inpatient settings. It is performed placing a low-frequency(≤ 2 MHz) tr...Non-invasive Doppler ultrasonographic study of cerebral arteries [transcranial Doppler(TCD)] has been extensively applied on both outpatient and inpatient settings. It is performed placing a low-frequency(≤ 2 MHz) transducer on the scalp of the patient over specific acoustic windows, in order to visualize the intracranial arterial vessels and to evaluate the cerebral blood flow velocity and its alteration in many different conditions. Nowadays the most widespread indication for TCD in outpatient setting is the research of right to left shunting, responsable of so called "paradoxical embolism", most often due to patency of foramen ovale which is responsable of the majority of cryptogenic strokes occuring in patients younger than 55 years old. TCD also allows to classify the grade of severity of such shunts using the so called "microembolic signal grading score". In addition TCD has found many useful applications in neurocritical care practice. It is useful on both adults and children for day-to-day bedside assessment of critical conditions including vasospasm in subarachnoidal haemorrhage(caused by aneurysm rupture or traumatic injury), traumatic brain injury, brain stem death. It is used also to evaluate cerebral hemodynamic changes after stroke. It also allows to investigate cerebral pressure autoregulation and for the clinical evaluation of cerebral autoregulatory reserve.展开更多
BACKGROUND Cardiogenic embolism caused by patent foramen ovale(PFO)is a common etiology of cryptogenic stroke(CS),particularly in young and middle-aged patients.Studies about right-to-left shunt(RLS)detection using co...BACKGROUND Cardiogenic embolism caused by patent foramen ovale(PFO)is a common etiology of cryptogenic stroke(CS),particularly in young and middle-aged patients.Studies about right-to-left shunt(RLS)detection using contrast-enhanced transcranial Doppler(c-TCD)are numerous.According to the time phase and number of microbubbles detected on c-TCD,RLS can be classified and graded.We hypothesized that the characteristics of an infarction lesion on diffusion-weighted imaging differs when combining the type and grade of RLS on c-TCD in patients with PFO-related CS.AIM To explore the characteristics of infarction lesions on diffusion-weighted imaging when combining the RLS type and grade determined by c-TCD.METHODS We retrospectively evaluated CS patients from August 2015 to December 2019 at a tertiary hospital.In total,111 PFO-related CS patients were divided according to whether RLS was permanent(microbubbles detected both at resting state and after the Valsalva maneuver)or latent(microbubbles detected only after the Valsalva maneuver)on c-TCD.Each group was subdivided into small,mild and large RLS according to the grade of shunt on c-TCD.A normal control group was composed of 33 patients who suffered from simple dizziness.Intragroup and intergroup differences were analyzed in terms of clinical,laboratory and diffusion-weighted imaging lesion characteristics.The correlation between RLS grade evaluated by c-TCD and size of PFO determined by transesophageal echocardiography were also analyzed.RESULTS In 111 patients with PFO-related CS,68 had permanent RLS and 43 had latent RLS.Clinical characteristics and laboratory tests were not significantly different among the permanent RLS,latent RLS and normal control groups.The proportion of patients with multiple territory lesions in the permanent RLS group(50%)was larger than that in the latent RLS group(27.91%;P=0.021).Posterior circulation was more likely to be affected in the latent RLS group than in the permanent RLS group(30.23%vs 8.82%,P=0.004).Permanent-large and latent-large RLS were both more likely to be related to multiple(P_(trend)=0.017 and 0.009,respectively),small(P_(trend)=0.035 and 0.006,respectively)and cortical(P_(trend)=0.031 and 0.033,respectively)lesions.The grade of RLS evaluated by c-TCD was correlated to the size of PFO determined by transesophageal echocardiography(r=0.758,P<0.001).CONCLUSION Distribution of the infarct suggested the possible type of RLS.Multiple,small and cortical infarcts suggest large RLS induced by a large PFO.展开更多
Objective To explore the effect of locally using dexamethasone on the blood flow velocity in the middle cerebral artery(FVmca) and cerebral edema after brain injury. Methods 20 rabbits were classified to 2 groups, gro...Objective To explore the effect of locally using dexamethasone on the blood flow velocity in the middle cerebral artery(FVmca) and cerebral edema after brain injury. Methods 20 rabbits were classified to 2 groups, group A( the control group) and B (the treated group). An experimental rabbit model was conducted to contusion by bone window plasty with extradural hitting. Group B was treated by locally infiltrating of dexamethasone at equidistance to lesions. Group A was given normal saline the same way as Group B. The changes of FVmca using trans－cranial Doppler and moisture in brain tissues were observed. Results The normal value of FVmca was (31.8± 4.5)cm/s, while the value of FVmca in group A and B were (15.4± 3.9)cm/s and (22.1± 3.5)cm/s separately.Water content in damaged hemisphere in Group A and B were (81.54± 0.55)％ and (79.35± 0.50)％ respectively. There was a significant difference between the 2 groups (P<0.05). The levels of FVmca in group A and B were lower than that of control and there was also a significant difference between group A and B (P<0.05).Conclusions FVmca decreased and the brain moisture increased after brain injury while FVmca increased and the brain moisture reduced after treatment with dexamethasone. It demonstreated that local treatment of dexamethasone had an obvious therapeutical effect on brain injury.展开更多
BACKGROUND： Latest researches at home and abroad indicate that glycerol trinitrate plays its function because it can metabolize into nitrogen monoxide （NO） in vivo. OBJECTIVE： To study the therapeutic effects of N...BACKGROUND： Latest researches at home and abroad indicate that glycerol trinitrate plays its function because it can metabolize into nitrogen monoxide （NO） in vivo. OBJECTIVE： To study the therapeutic effects of NO vector of ultrasonic atomizing inhalation on vertebro-basilar artery insufficiency （VBI） through transcranial Doppler （TCD） detection and serum NO content and indirect effect of TCD on cerebral blood flow changes. DESIGN： Randomized grouping and controlled clinical study. SETTING： Department of Neurology, the Fourth People＇s Hospital of Jinan. PARTICIPANTS： A total of 130 patients who were diagnosed as VBI were selected from Department of Neurology, the Fourth People＇s Hospital of Jinan from December 2001 to December 2005. The involved inpatients were checked by CT and MRI, and met the VBI diagnostic standard enacted by the Fourth National Academic Meeting of Cerebrovascular Disease in 1995. All patients and their relatives provided the confumed consent. They were randomly divided into low-dose treatment group （n =60）, high-lose treatment group （n =30） and control group （n =40）. METHODS： Patients in the low-dose and high-dose treatment groups were given ultrasonic atomizing inhalation of 3 mg and 5 mg glycerol trinitrate, respectively, for 20 minutes, once a day. In addition, ligustrazine and energy mixture were used once a day for three days in a course. Cases in the control group were only given ligustrazine and energy mixture. All selected cases accepted TCD, blood NO content was checked at the time of beginning, after the first time and after a period of treatment. According to the TCD test, VBI patients were divided into two groups （high-low flow velocity）. The vertebral artery （VA） and basal artery （BA） of left or right sides were detected by 2 Hz detector via occipital window. MAIN OUTCOME MEASURES： ①Blood flow velocity of systolic phase, blood flow velocity of diastole phase and vascular resistance in left and right VA and BA detected by using TCD before treatment, after treatment for one course; ②content of serum NO indirectly measured by using nitric acid disoxidation technique. RESULTS： All 130 VBI patients were involved in the final analysis. ①Changes of hemodynamic indexes： Systolic phase of VA and diastole phase of BA were higher in low-dose treatment group than that in the control group after first treatment, and there was significant difference （P 〈 0.05）; meanwhile, systolic phase and diastole phase of VA and systolic phase of BA were also higher in treatment group than that in the control group after one course （P 〈 0.05）. However, both systolic phase and diastole phase of VA and BA were lower in high-dose treatment group than that in the control group after first treatment and one course, and there was significant difference （P 〈 0.05）. ②Content of serum NO： After first treatment, there was no significant difference between low-dose treatment group and high-dose treatment group （P 〉 0.05）; but both groups were higher than control group, and there was significant difference （P 〈 0.05, 0.01）. CONCLUSION： NO vector of ultrasonic atomizing inhalation can improve VBI so as to improve cerebral blood-supply state.展开更多
Sickle-cell disease (SCD) is the most common cause of ischemic stroke in children and it happens in about 11% of patients between the age of 2 and 20 years old. About 7% of the world population is affected by hemoglob...Sickle-cell disease (SCD) is the most common cause of ischemic stroke in children and it happens in about 11% of patients between the age of 2 and 20 years old. About 7% of the world population is affected by hemoglobin disorders, mostly sickle cell anemia. SCD has a high prevalence in the population of African offspring and it is a public health problem in Brazil that affects more than 30,000 million people. Prevention of primary stroke might be feasible with a way to identify children at greatest risk. Transcranial Doppler Ultrasonography (TCD) to SCD patients can be a valuable service that results in a significant decrease of first stroke rates. In this work, we present a review about TCD as an effective strategy to detect children with SCD who are at risk for stroke.展开更多
Aim. Comparison of the trascranial Doppler (TCD) characteristics of cerebral circulation in persistent vegetative status (PVS), locked in syndrome and brain death patients. Methods. Using ...Aim. Comparison of the trascranial Doppler (TCD) characteristics of cerebral circulation in persistent vegetative status (PVS), locked in syndrome and brain death patients. Methods. Using TCD ultrasound to detect the flow velocity and waveform patterns of middle cerebral artery (MCA) and basilar artery (BA) in patients with PVS, locked in syndrome and brain death. Results. The mean velocities of middle cerebral artery (Vmca) and basilar artery (Vba) were 30.0cm/s and 24.3cm/s in PVS patients respectively, which decreased 45.0% and 14.4% in comparing with normal value. For patients with locked in syndrome, Vmca and Vba were 49.7cm/s and 9.8cm/s, which decreased 5.0% and 61.7% than the normal value respectively. These results showed that the decrease of anterior circulation was predominant in PVS, and the decrease of posterior circulation was predominant in locked in syndrome. A unique diastolic reverse flow, short peak systolic wave or undetectable flow signal in middle cerebral artery were predominant in brain death patients, which was completely different from that of either PVS or locked in syndrome. Conclusion. TCD was a valuable tool in distinguishing PVS, locked in syndrome and brain death patients according to the differences in velocities and patterns of anterior and posterior cerebral arteries.展开更多
Transcranial Doppler(TCD) is useful for investigation of intracranial arterial blood flow and can be used to detect a real-time embolic signal. Unfortunately, artefacts can mimic the embolic signal, complicating inter...Transcranial Doppler(TCD) is useful for investigation of intracranial arterial blood flow and can be used to detect a real-time embolic signal. Unfortunately, artefacts can mimic the embolic signal, complicating interpretation and necessitating expert-level opinion to distinguish the two. Resolving this situation is critical to achieve improved accuracy and utility of TCD for patients with disrupted intracranial arterial blood flow, such as stroke victims. A common type of stroke encountered in the clinic is cryptogenic stroke(or stroke with undetermined etiology), and patent foramen ovale(PFO) has been associated with the condition. An early clinical trial of PFO closure effect on secondary stroke prevention failed to demonstrate any benefit for the therapy, and research into the PFO therapy generally diminished. However, the recent publication of large randomized control trials with demonstrated benefit of PFO closure for recurrent stroke prevention has rekindled the interest in PFO in patients with cryptogenic stroke. To confirm that emboli across the PFO can reach the brain, TCD should be applied to detect the air embolic signal after injection of agitated saline bubbles at the antecubital vein. In addition, the automated embolic signal detection method should further facilitate use of TCD for air embolic signal detection after the agitated saline bubbles injection in patients with cryptogenic stroke and PFO.展开更多
BACKGROUND： If changes of hemodynamics in internal or external cranial artery and stenosis of atherosclerosis are found eady, patients with transient ischemic attack （TIA） may be treated at an eady phase so as to p...BACKGROUND： If changes of hemodynamics in internal or external cranial artery and stenosis of atherosclerosis are found eady, patients with transient ischemic attack （TIA） may be treated at an eady phase so as to prevent and decrease the onset of cerebral infarction. Carotid Doppler can analyze carotid canal wall, hemodynamic properties and stenosis, and changes of plaque morphology; however, transcranial Doppler （TCD） can evaluate vascular stenosis and occlusion and judge collateral circulation in cranium through detecting velocity and direction of blood flow. Can the association of them increase the diagnostic rate of TIA？ OB3ECTIVE： To evaluate the effect of the association of carotid Doppler and TCD on TIA in internal carotid artery. DESIGN： Contrast observational study SETTING： Department of Neuroelectrophysiology, Central People＇s Hospital of Huizhou PARTICIPANTS： A total of 54 patients with TIA in internal carotid artery were selected from the Department of Neurology of Huizhou Central People＇s Hospital from May 2004 to June 2005. There were 35 males and 24 females aged 46-81 years. The clinical situation was asthenia of single limb, hemiplegia, anaesthesia of single upper or lower limb, hemianesthesia, sensory disorder and aphasia. The symptoms lasted for less than 2 hours. All cases were diagnosed with CT, and those who had pathological changes of acute cerebral infarction and history of cardiac disease were excluded. Additionally, 50 healthy subjects who were regarded as control group were selected from the Department of Neurology of Huizhou Central People＇s Hospital. There were 30 males and 20 females aged 45-80 years. All subjects were consent. METHODS： HD15000 color Doppler ultrasound （Philips Company, USA） and Muliti-DopX2 TCD （DWL Company, Germany） were used to detect hemodynamics, stenosis and distribution of atherosclerosis in carotid artery and internal carotid artery. Evaluation of marker： Stenosis was calculated by the ratio between the minimal cavity and vascular sectional area at the maximal site of plaque （mild： stenosis 〈 50%; moderate and severe： stenosis t〉 50%）. With TCD, the following results were regarded as stenosis： blood velocity of average envelope 〉 120 cm/s （diagnostic criteria of vascular stenosis of basilar artery： blood velocity of average envelope 〉 80 cm/s）, increase and segmental property of blood flow, and murmu of turbulent flow and vessel. MAIN OUTCOME MEASURES： Positive rate of atherosclerosis and incidence of stenosis with carotid Doppler and TCD. RESULTS： All 54 TIA patients and 50 healthy subjects were involved in the final analysis. ① Results of carotid Doppler： Atherosclerosis and stenosis were obvious in experimental group. Positive rate of atherosclerosis was 85% （46/54） and incidence of stenosis of carotid artery was 41% （22/54）, which were higher than those in control group [52% （26/54）, 41% （22/54）, x^2 = 13.42, 10.90, P 〈 0.01]. ② Results of TCD： In experimental group, positive rate of atherosclerosis at base of skull was 89% （48/54） and incidence of stenosis of internal cranial artery was 48% （26/54）, which were higher than those in control group [62% （31/50）, 0, x^2 = 10.28, 32.00, P 〈 0.01]. Stenosis of artery was mainly involved in middle cerebral artery, initial segment and crotch of carotid artery. CONCLUSION： The association of carotid Doppler and TCD can increase clinically diagnostic rate of TIA and provide bases for apposition and intensity of TIA lesion.展开更多
文摘Non-invasive Doppler ultrasonographic study of cerebral arteries [transcranial Doppler(TCD)] has been extensively applied on both outpatient and inpatient settings. It is performed placing a low-frequency(≤ 2 MHz) transducer on the scalp of the patient over specific acoustic windows, in order to visualize the intracranial arterial vessels and to evaluate the cerebral blood flow velocity and its alteration in many different conditions. Nowadays the most widespread indication for TCD in outpatient setting is the research of right to left shunting, responsable of so called "paradoxical embolism", most often due to patency of foramen ovale which is responsable of the majority of cryptogenic strokes occuring in patients younger than 55 years old. TCD also allows to classify the grade of severity of such shunts using the so called "microembolic signal grading score". In addition TCD has found many useful applications in neurocritical care practice. It is useful on both adults and children for day-to-day bedside assessment of critical conditions including vasospasm in subarachnoidal haemorrhage(caused by aneurysm rupture or traumatic injury), traumatic brain injury, brain stem death. It is used also to evaluate cerebral hemodynamic changes after stroke. It also allows to investigate cerebral pressure autoregulation and for the clinical evaluation of cerebral autoregulatory reserve.
基金People’s Livelihood Science and Technology Project(Research on Application of Key Technologies)of Suzhou(No.SS202061)Technical Cooperation Project of Soochow University(No.H211064).
文摘BACKGROUND Cardiogenic embolism caused by patent foramen ovale(PFO)is a common etiology of cryptogenic stroke(CS),particularly in young and middle-aged patients.Studies about right-to-left shunt(RLS)detection using contrast-enhanced transcranial Doppler(c-TCD)are numerous.According to the time phase and number of microbubbles detected on c-TCD,RLS can be classified and graded.We hypothesized that the characteristics of an infarction lesion on diffusion-weighted imaging differs when combining the type and grade of RLS on c-TCD in patients with PFO-related CS.AIM To explore the characteristics of infarction lesions on diffusion-weighted imaging when combining the RLS type and grade determined by c-TCD.METHODS We retrospectively evaluated CS patients from August 2015 to December 2019 at a tertiary hospital.In total,111 PFO-related CS patients were divided according to whether RLS was permanent(microbubbles detected both at resting state and after the Valsalva maneuver)or latent(microbubbles detected only after the Valsalva maneuver)on c-TCD.Each group was subdivided into small,mild and large RLS according to the grade of shunt on c-TCD.A normal control group was composed of 33 patients who suffered from simple dizziness.Intragroup and intergroup differences were analyzed in terms of clinical,laboratory and diffusion-weighted imaging lesion characteristics.The correlation between RLS grade evaluated by c-TCD and size of PFO determined by transesophageal echocardiography were also analyzed.RESULTS In 111 patients with PFO-related CS,68 had permanent RLS and 43 had latent RLS.Clinical characteristics and laboratory tests were not significantly different among the permanent RLS,latent RLS and normal control groups.The proportion of patients with multiple territory lesions in the permanent RLS group(50%)was larger than that in the latent RLS group(27.91%;P=0.021).Posterior circulation was more likely to be affected in the latent RLS group than in the permanent RLS group(30.23%vs 8.82%,P=0.004).Permanent-large and latent-large RLS were both more likely to be related to multiple(P_(trend)=0.017 and 0.009,respectively),small(P_(trend)=0.035 and 0.006,respectively)and cortical(P_(trend)=0.031 and 0.033,respectively)lesions.The grade of RLS evaluated by c-TCD was correlated to the size of PFO determined by transesophageal echocardiography(r=0.758,P<0.001).CONCLUSION Distribution of the infarct suggested the possible type of RLS.Multiple,small and cortical infarcts suggest large RLS induced by a large PFO.
文摘Objective To explore the effect of locally using dexamethasone on the blood flow velocity in the middle cerebral artery(FVmca) and cerebral edema after brain injury. Methods 20 rabbits were classified to 2 groups, group A( the control group) and B (the treated group). An experimental rabbit model was conducted to contusion by bone window plasty with extradural hitting. Group B was treated by locally infiltrating of dexamethasone at equidistance to lesions. Group A was given normal saline the same way as Group B. The changes of FVmca using trans－cranial Doppler and moisture in brain tissues were observed. Results The normal value of FVmca was (31.8± 4.5)cm/s, while the value of FVmca in group A and B were (15.4± 3.9)cm/s and (22.1± 3.5)cm/s separately.Water content in damaged hemisphere in Group A and B were (81.54± 0.55)％ and (79.35± 0.50)％ respectively. There was a significant difference between the 2 groups (P<0.05). The levels of FVmca in group A and B were lower than that of control and there was also a significant difference between group A and B (P<0.05).Conclusions FVmca decreased and the brain moisture increased after brain injury while FVmca increased and the brain moisture reduced after treatment with dexamethasone. It demonstreated that local treatment of dexamethasone had an obvious therapeutical effect on brain injury.
文摘BACKGROUND： Latest researches at home and abroad indicate that glycerol trinitrate plays its function because it can metabolize into nitrogen monoxide （NO） in vivo. OBJECTIVE： To study the therapeutic effects of NO vector of ultrasonic atomizing inhalation on vertebro-basilar artery insufficiency （VBI） through transcranial Doppler （TCD） detection and serum NO content and indirect effect of TCD on cerebral blood flow changes. DESIGN： Randomized grouping and controlled clinical study. SETTING： Department of Neurology, the Fourth People＇s Hospital of Jinan. PARTICIPANTS： A total of 130 patients who were diagnosed as VBI were selected from Department of Neurology, the Fourth People＇s Hospital of Jinan from December 2001 to December 2005. The involved inpatients were checked by CT and MRI, and met the VBI diagnostic standard enacted by the Fourth National Academic Meeting of Cerebrovascular Disease in 1995. All patients and their relatives provided the confumed consent. They were randomly divided into low-dose treatment group （n =60）, high-lose treatment group （n =30） and control group （n =40）. METHODS： Patients in the low-dose and high-dose treatment groups were given ultrasonic atomizing inhalation of 3 mg and 5 mg glycerol trinitrate, respectively, for 20 minutes, once a day. In addition, ligustrazine and energy mixture were used once a day for three days in a course. Cases in the control group were only given ligustrazine and energy mixture. All selected cases accepted TCD, blood NO content was checked at the time of beginning, after the first time and after a period of treatment. According to the TCD test, VBI patients were divided into two groups （high-low flow velocity）. The vertebral artery （VA） and basal artery （BA） of left or right sides were detected by 2 Hz detector via occipital window. MAIN OUTCOME MEASURES： ①Blood flow velocity of systolic phase, blood flow velocity of diastole phase and vascular resistance in left and right VA and BA detected by using TCD before treatment, after treatment for one course; ②content of serum NO indirectly measured by using nitric acid disoxidation technique. RESULTS： All 130 VBI patients were involved in the final analysis. ①Changes of hemodynamic indexes： Systolic phase of VA and diastole phase of BA were higher in low-dose treatment group than that in the control group after first treatment, and there was significant difference （P 〈 0.05）; meanwhile, systolic phase and diastole phase of VA and systolic phase of BA were also higher in treatment group than that in the control group after one course （P 〈 0.05）. However, both systolic phase and diastole phase of VA and BA were lower in high-dose treatment group than that in the control group after first treatment and one course, and there was significant difference （P 〈 0.05）. ②Content of serum NO： After first treatment, there was no significant difference between low-dose treatment group and high-dose treatment group （P 〉 0.05）; but both groups were higher than control group, and there was significant difference （P 〈 0.05, 0.01）. CONCLUSION： NO vector of ultrasonic atomizing inhalation can improve VBI so as to improve cerebral blood-supply state.
文摘Sickle-cell disease (SCD) is the most common cause of ischemic stroke in children and it happens in about 11% of patients between the age of 2 and 20 years old. About 7% of the world population is affected by hemoglobin disorders, mostly sickle cell anemia. SCD has a high prevalence in the population of African offspring and it is a public health problem in Brazil that affects more than 30,000 million people. Prevention of primary stroke might be feasible with a way to identify children at greatest risk. Transcranial Doppler Ultrasonography (TCD) to SCD patients can be a valuable service that results in a significant decrease of first stroke rates. In this work, we present a review about TCD as an effective strategy to detect children with SCD who are at risk for stroke.
文摘Aim. Comparison of the trascranial Doppler (TCD) characteristics of cerebral circulation in persistent vegetative status (PVS), locked in syndrome and brain death patients. Methods. Using TCD ultrasound to detect the flow velocity and waveform patterns of middle cerebral artery (MCA) and basilar artery (BA) in patients with PVS, locked in syndrome and brain death. Results. The mean velocities of middle cerebral artery (Vmca) and basilar artery (Vba) were 30.0cm/s and 24.3cm/s in PVS patients respectively, which decreased 45.0% and 14.4% in comparing with normal value. For patients with locked in syndrome, Vmca and Vba were 49.7cm/s and 9.8cm/s, which decreased 5.0% and 61.7% than the normal value respectively. These results showed that the decrease of anterior circulation was predominant in PVS, and the decrease of posterior circulation was predominant in locked in syndrome. A unique diastolic reverse flow, short peak systolic wave or undetectable flow signal in middle cerebral artery were predominant in brain death patients, which was completely different from that of either PVS or locked in syndrome. Conclusion. TCD was a valuable tool in distinguishing PVS, locked in syndrome and brain death patients according to the differences in velocities and patterns of anterior and posterior cerebral arteries.
文摘Transcranial Doppler(TCD) is useful for investigation of intracranial arterial blood flow and can be used to detect a real-time embolic signal. Unfortunately, artefacts can mimic the embolic signal, complicating interpretation and necessitating expert-level opinion to distinguish the two. Resolving this situation is critical to achieve improved accuracy and utility of TCD for patients with disrupted intracranial arterial blood flow, such as stroke victims. A common type of stroke encountered in the clinic is cryptogenic stroke(or stroke with undetermined etiology), and patent foramen ovale(PFO) has been associated with the condition. An early clinical trial of PFO closure effect on secondary stroke prevention failed to demonstrate any benefit for the therapy, and research into the PFO therapy generally diminished. However, the recent publication of large randomized control trials with demonstrated benefit of PFO closure for recurrent stroke prevention has rekindled the interest in PFO in patients with cryptogenic stroke. To confirm that emboli across the PFO can reach the brain, TCD should be applied to detect the air embolic signal after injection of agitated saline bubbles at the antecubital vein. In addition, the automated embolic signal detection method should further facilitate use of TCD for air embolic signal detection after the agitated saline bubbles injection in patients with cryptogenic stroke and PFO.
文摘BACKGROUND： If changes of hemodynamics in internal or external cranial artery and stenosis of atherosclerosis are found eady, patients with transient ischemic attack （TIA） may be treated at an eady phase so as to prevent and decrease the onset of cerebral infarction. Carotid Doppler can analyze carotid canal wall, hemodynamic properties and stenosis, and changes of plaque morphology; however, transcranial Doppler （TCD） can evaluate vascular stenosis and occlusion and judge collateral circulation in cranium through detecting velocity and direction of blood flow. Can the association of them increase the diagnostic rate of TIA？ OB3ECTIVE： To evaluate the effect of the association of carotid Doppler and TCD on TIA in internal carotid artery. DESIGN： Contrast observational study SETTING： Department of Neuroelectrophysiology, Central People＇s Hospital of Huizhou PARTICIPANTS： A total of 54 patients with TIA in internal carotid artery were selected from the Department of Neurology of Huizhou Central People＇s Hospital from May 2004 to June 2005. There were 35 males and 24 females aged 46-81 years. The clinical situation was asthenia of single limb, hemiplegia, anaesthesia of single upper or lower limb, hemianesthesia, sensory disorder and aphasia. The symptoms lasted for less than 2 hours. All cases were diagnosed with CT, and those who had pathological changes of acute cerebral infarction and history of cardiac disease were excluded. Additionally, 50 healthy subjects who were regarded as control group were selected from the Department of Neurology of Huizhou Central People＇s Hospital. There were 30 males and 20 females aged 45-80 years. All subjects were consent. METHODS： HD15000 color Doppler ultrasound （Philips Company, USA） and Muliti-DopX2 TCD （DWL Company, Germany） were used to detect hemodynamics, stenosis and distribution of atherosclerosis in carotid artery and internal carotid artery. Evaluation of marker： Stenosis was calculated by the ratio between the minimal cavity and vascular sectional area at the maximal site of plaque （mild： stenosis 〈 50%; moderate and severe： stenosis t〉 50%）. With TCD, the following results were regarded as stenosis： blood velocity of average envelope 〉 120 cm/s （diagnostic criteria of vascular stenosis of basilar artery： blood velocity of average envelope 〉 80 cm/s）, increase and segmental property of blood flow, and murmu of turbulent flow and vessel. MAIN OUTCOME MEASURES： Positive rate of atherosclerosis and incidence of stenosis with carotid Doppler and TCD. RESULTS： All 54 TIA patients and 50 healthy subjects were involved in the final analysis. ① Results of carotid Doppler： Atherosclerosis and stenosis were obvious in experimental group. Positive rate of atherosclerosis was 85% （46/54） and incidence of stenosis of carotid artery was 41% （22/54）, which were higher than those in control group [52% （26/54）, 41% （22/54）, x^2 = 13.42, 10.90, P 〈 0.01]. ② Results of TCD： In experimental group, positive rate of atherosclerosis at base of skull was 89% （48/54） and incidence of stenosis of internal cranial artery was 48% （26/54）, which were higher than those in control group [62% （31/50）, 0, x^2 = 10.28, 32.00, P 〈 0.01]. Stenosis of artery was mainly involved in middle cerebral artery, initial segment and crotch of carotid artery. CONCLUSION： The association of carotid Doppler and TCD can increase clinically diagnostic rate of TIA and provide bases for apposition and intensity of TIA lesion.
