The effect of low voltage and low concentration contrast agent on image quality of coronary CT angiography,radiation dose and iodine intake was evaluated.A total of 121 patients with body mass index(BMI)<26 kg/m2 a...The effect of low voltage and low concentration contrast agent on image quality of coronary CT angiography,radiation dose and iodine intake was evaluated.A total of 121 patients with body mass index(BMI)<26 kg/m2 and heart rate(HR)<70 beats/min were randomly divided into four groups:group A(n=31,80 kVp,270 mgl/mL);group B(n=33,100 kVp,270 mgl/mL);group C(h=30,100 kVp,320 mgl/mL);group D(w=27,100 kVp,400 mgl/mL).The automatic current modulation system and the iterative algorithm for reconstruction were adopted in each group.The CT values and SD values of the aortic root(AR),subcutaneous fat,left coronary artery opening(LCA),and right coronary artery opening(RCA)were measured in all groups,the signalto-noise ratio(SNR)and contrast noise ratio(CNR)were calculated,and effective radiation dose and iodine intake were recorded.The subjective assessment for image quality was performed by two physicians using a 4-point scale.The results were compared using the one-way ANOVA and rank sum tests.The image quality of the four groups met the clinical diagnostic requirements.The CT values of AR in groups A,B,C,and D were 537.6±71.4,447.2±81.9,445.2±64.9 and 518.5±94.9 Hu,respectively,with no significant difference between group A and group D,or between group B and group C,while CT values in groups B and C were significantly lower than those in groups A and D(P<0.05).In groups A,B,C,and D,the LCA SNR values were 22.7±9.1,23.3±9.1,23.3±7.7 and 26.6±8.9,and the RCA CNR values were 26.9±9.&28.5±11.4,27.7土&8 and 32」±10.6,respectively.The AR visual scores in groups A,B,C and D were 3.8±0.2,3.9±0.3,3.9±0.3 and 4.0±0.3,respectively.There were no significant differences in SNR,CNR and visual score among the four groups(P>0.05).The radiation doses in groups A,B,C and D were 2.6±1.4,3.6±1.&4.9±3.5 and 4.9±2.8 mSv,respectively.The radiation dose in group A was significantly less than that in the rest three groups(P<0.05).The iodine intakes in groups A,B,C and D were 14.9±1.5,15.0±1.5,17.7±2.0 and 18.1±2.5 g,respectively.There was no significant difference in the intake of iodine between groups C and D,or between groups A and B,while iodine intake in groups A and B were significantly reduced as compared with that in groups C and D(P<0.05).It was concluded that for patients with low BMI and controlled HR,compared to 100 kVp tube voltage combined with multiple concentration contrast agents,80 kVp combined with 270 mgl/mL contrast agent is enough to ensure the quality of the images,and can reduce the radiation dose significantly,while reducing the amount of iodine intake notably,thus reducing the incidence of adverse reaction.展开更多
Objective This study aimed to explore the feasibility of enhancing image quality in computed tomography(CT) pulmonary angiography (CTPA) and reducing radiation dose using the nonlinear blending (NLB)technique of dual-...Objective This study aimed to explore the feasibility of enhancing image quality in computed tomography(CT) pulmonary angiography (CTPA) and reducing radiation dose using the nonlinear blending (NLB)technique of dual-energy CT.Methods A total of 61 patients scheduled for CTPA were enrolled, and 30 patients underwent dual-energyscanning. Nonlinear blending images (NLB group) and three groups of linear blending images (LB group,80 kV group, and 140 kV group) were reconstructed after scanning;31 patients underwent single-energyscanning (120 kV group). The CT values and standard deviations of the pulmonary trunk, left and rightpulmonary arteries, and ipsilateral back muscle at the bifurcation level of the left and right pulmonaryarteries were measured. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the fivegroups were calculated. The subjective image quality of the five groups was assessed. The radiation dosesof the dual- and single-energy groups were recorded and calculated.Results The CNR and SNR values of blood vessels in the NLB group were significantly higher than thosein the LB, 140 kV, and 80 kV groups (CNR of pulmonary artery trunk: t = 3.50, 4.06, 7.17, all P < 0.05;SNRof pulmonary trunk: t = 3.76, 4.71, 6.92, all P < 0.05). There were no statistical differences in the CNR andSNR values between the NLB group and 120 kV group (P > 0.05). The effective radiation dose of the dualenergygroup was lower than that of the single-energy group (t = –4.52, P < 0.05). The subjective scores ofimages in the NLB group were the highest (4.28 ± 0.74).Conclusion The NLB technique of dual-energy CT can improve the image quality of CTPA and reducethe radiation dose, providing more reliable imaging data for the clinical diagnosis of pulmonary embolism.展开更多
Objective:To analyze the imaging effect and accuracy of 64-slice spiral CT in the diagnosis of coronary artery stenosis.Methods:30 patients with suspected coronary heart disease admitted to our hospital from March 202...Objective:To analyze the imaging effect and accuracy of 64-slice spiral CT in the diagnosis of coronary artery stenosis.Methods:30 patients with suspected coronary heart disease admitted to our hospital from March 2022 to March 2023 were selected.All patients underwent both 64-slice spiral CT and digital subtraction angiography(DSA).DSA is considered the gold standard for diagnosis,so it was used to analyze the diagnostic performance of 64-slice spiral CT.Results:(1)The diagnostic results of digital subtraction angiography and 64-slice spiral CT was analyzed and compared with each other.The 64-slice spiral CT had an accuracy of 96.67%(29/30),a sensitivity 96.55%(28/29),and a specificity of 100.00%(1/1)in diagnosing coronary artery stenosis.(2)There was no significant difference between 64-slice spiral CT and digital subtraction angiography in the positive detection rate of anterior descending artery lesion,the positive detection rate of left main lesion,the positive detection rate of left circumflex artery lesion and the positive detection rate of right coronary artery lesion(P>0.05).(3)There was no significant difference between 64-slice spiral CT examination and DSA examination in identifying mild stenosis,moderate stenosis,and severe stenosis of coronary arteries(P>0.05).Conclusion:64-slice spiral CT examination can accurately determine the degree of occlusion of coronary arteries,which allows for the accurate diagnosis of coronary artery stenosis.展开更多
Objectives To investigate the morphologic characteristics of intramural hematoma(IMH)on CT angiography(CTA),and evaluate the possible correlation of serum C-reactive protein(CRP)with morphologic characteristics of IMH...Objectives To investigate the morphologic characteristics of intramural hematoma(IMH)on CT angiography(CTA),and evaluate the possible correlation of serum C-reactive protein(CRP)with morphologic characteristics of IMH.Material and Methods Forty-two patients who were initially diagnosed as IMH by aortic CTA and also had serum CRP examination on the same day of CTA were enrolled in this retrospective study,including 30 males and 12 females,with the mean age of 61±14 years old.The volumetric CT data were retrospectively processed and analyzed on post-processing workstation.Based on the thickness of IMH and the length-area curve,the crosssectional area of true lumen and total vessel were measured,the hematoma-vessel ratio(HVR)was calculated.Imaging characteristics were compared between patients who had pathological elevated CRP(>0.8 mg/dl)and those did not.Spearman correlation analyses of CRP level and morphological characteristics of IMH were performed,and the receiver operating characteristic(ROC)curve was used to evaluate the diagnostic validity of CRP.Results Of all 42 IMH patients,the mean serum CRP was 3.94±4.71 mg/dl,and the mean HVR was 46.7%±14.2%.HVR in patients with elevated CRP was significantly higher than those with normal CRP(49.7%±15.0%vs.40.7%±10.5%,P=0.030).HVR was mildly correlated with CRP in all patients(r=0.48,P<0.001).CRP levels differed neither between patients with Stanford type A and B(P=0.207),nor between patients with and without intimal disruption(P=0.230).To discriminate HVR>47%(the mean value),the area under curve(AUC)were 0.700(95%CI:0.535-0.865)for CRP at a cutoff point of 3.55 mg/dl,with a sensitivity of 54.5%and a specificity of 90.0%.Conclusion CRP was mildly correlated with the severity of cross-sectional hematoma area of IMH,but not with Stanford types and the presence of intimal disruption.展开更多
Objective: To identify the morphological parameters that are related to intracranial aneurysms(IAs) rupture using a case-control model.Methods: A total of 107 patients with multiple IAs and aneurysmal subarachnoid hem...Objective: To identify the morphological parameters that are related to intracranial aneurysms(IAs) rupture using a case-control model.Methods: A total of 107 patients with multiple IAs and aneurysmal subarachnoid hemorrhage between August 2011 and February 2017 were enrolled in this study.Characteristics of IAs location, shape, neck width, perpendicular height, depth, maximum size, flow angle, parent vessel diameter(PVD), aspect ratio(AR) and size ratio(SR) were evaluated using CT angiography.Multiple logistic regression analysis was used to identify the independent risk factors associated with IAs rupture.Receiver operating characteristic curve analysis was performed on the final model, and the optimal thresholds were obtained.Results: IAs located in the internal carotid artery(ICA) was associated with a negative risk of rupture, whereas AR, SR1(height/PVD) and SR2(depth/PVD) were associated with increased risk of rupture.When SR was calculated differently, the odds ratio values of these factors were also different.The receiver operating characteristic curve showed that AR, SR1 and SR2 had cut-off values of 1.01, 1.48 and 1.40, respectively.SR3(maximum size/PVD) was not associated with IAs rupture.Conclusions: IAs located in the ICA are associated with a negative risk of rupture, while high AR(>1.01), SR1(>1.48) or SR2(>1.40) are risk factors for multiple IAs rupture.展开更多
BACKGROUND:This study was undertaken to identify the prevalence of pulmonary embolism(PE) in the emergency department(ED) of an urban teaching hospital and also to test a Bayesian model in estimating the number of CT ...BACKGROUND:This study was undertaken to identify the prevalence of pulmonary embolism(PE) in the emergency department(ED) of an urban teaching hospital and also to test a Bayesian model in estimating the number of CT pulmonary angiography(CTA) expected to be performed in an emergency department.METHODS:The data for this study was obtained through a retrospective review of electronic medical records for all ED patients suspected of PE who underwent chest CTA or ventilation perfusion scanning(V/Q) between 2009 and 2010.The data is presented as means and standard deviation for continuous variables and percentages with 95%confidence intervals(95%CI) for proportions.The prevalence of PE was used as pre-test probability in the Bayesian model.Post-test probability was obtained using a Fagan nomogram and likelihood ratios for CTA.RESULTS:A total of 778 patients(560 females) with mean age of 50 years(range 18-98 years)were enrolled(98.3%underwent chest CTA and 1.7%underwent V/Q scan).A total of 69 patients had PE,rendering an overall prevalence of 8.9%(95%CI,7.1%to 11.1%) for PE.We calculated that132 CTA's per year could be avoided in our institution,without compromising safe exclusions of PE(keeping post-test probability of PE below 2%).CONCLUSIONS:Despite differences in our patient populations and /or study designs,the prevalence of PE in our institution is about average compared to other institutions.Our proposed model for calculating redundant chest CTA is simple and can be used by institutions to identify overuse of CTA.展开更多
Basilar artery fenestration is a rare anatomical variation resulting from the failed fusion of the two vertebral arteries during embryonic life. In order of frequency, it is the second most common location of vascular...Basilar artery fenestration is a rare anatomical variation resulting from the failed fusion of the two vertebral arteries during embryonic life. In order of frequency, it is the second most common location of vascular fenestrations after the anterior communicating artery. Vertebrobasilar junction aneurysms are uncommon but often associated with basilar artery fenestration. We report the case of a fenestrated vertebrobasilar junction saccular aneurysm in a 57-year-old woman. The diagnosis was incidentally made on CT angiography which found the anatomical variant and the aneurysm. The radiological features illustrating this association are detailed here and a brief discussion of its pathogenesis and management was made. Vertebrobasilar junction aneurysms are rare and their presence should suggest an associated basilar fenestration.展开更多
Introduction: Rupture of intracranial aneurisms leads to severe morbidity and mortality. There are two modalities of treatment surgery and endovascular treatment. The diagnosis is made by angiography (DSA, CTA, RMA). ...Introduction: Rupture of intracranial aneurisms leads to severe morbidity and mortality. There are two modalities of treatment surgery and endovascular treatment. The diagnosis is made by angiography (DSA, CTA, RMA). The angiographic features used to assess the risk of the complications and choose the treatment modality are size, location and aneurism morphology. Materials and Methods: We reviewed and analyzed the computed tomographic angiography and magnetic resonance angiography of all patients admitted to the hospital of Mali with IAs from 2015 to 2021 either 7 years. Patients who were less than 18 years old, those with non-aneurysmal SAH, patients who request a discharge and those with an incomplete angiographic description of the IAs were excluded from the analysis. Results: We have collected 105 patients with 109 aneurysms. The sex ratio was 2/1 in favor of females. The mean age was 44.51 years with the range from 18 to 70 years. The presentation mode was subarachnoid hemorrhage (SAH) in 97% of cases. 76.19% had confirmed high blood pressure before the bleeding. 19.04% were diabetics. 98% of our patients have made a CT angiography and 2% have made MR angiography for the aneurysm diagnosis. 97.24% of aneurisms were located in the anterior part of the Willis circle. 39.44% of these aneurisms were the anterior communicating complex aneurysm. 27.52% of aneurysm had a small size, 42.20% had a medium size, 20.18% large size against 5.50% of the giant (Figure 3) and the middle cerebral artery was the most involved in the least. 95.41% of cases were saccular aneurysms against 4.59% fusiform. Conclusion: The angiographic feature of an intracranial aneurism in the Malian population may differ from other populations of the sub-region. The anterior communicating complex aneurysm is more common and the aneurism of the posterior part of the Willis circle is less common. We found the aneurism size ≥ 6 mm, ACA, MCA and Pcom more frequent.展开更多
Context: Cerebellar syndrome caused by disturbances of balance and coordination is not an uncommon neurological disorder. It has varied etiologies usually caused by tumor processes or suppurative collections. Vascular...Context: Cerebellar syndrome caused by disturbances of balance and coordination is not an uncommon neurological disorder. It has varied etiologies usually caused by tumor processes or suppurative collections. Vascular causes remain very rare, especially when it is a giant aneurysm of PICA representing 1% of intracranial aneurysms. Treating giant PICA aneurysms is a very difficult task for neurosurgeons because the surgical dissection can lead to severe damage due to the intimate relationship of PICA with the brainstem or nerve structures. We report a case of giant PICA aneurysm responsible for cerebellar syndrome successfully treated with surgery. The objective of this work is to draw the attention of practitioners to this unusual cause which can lead to diagnosis wandering and a lack of planning at the time of management. Case report: A 65 years old hypertensive patient was seen for a progressive disturbance of balance and walking disorder, but worsened in the last three months with no notion of fever. On admission, the patient was lucid, oriented in time and space and presented with static and kinetic cerebellar syndrome. Brain CT-scan without and with contrast revealed a tissular mass in the posterior fossa suggesting a tumor process, however, CT angiography showed a giant aneurysm of the PICA after reconstruction. A careful microdissection by a sub-occipital approach was decided. Opening the large cistern made it possible to visualize the aneurysm sack surrounded by a yellowish gliosis. The reclining and microdissection revealed the neck of the aneurysm, which was clipped to exclude the giant aneurysm in block. Postoperative follow-up was simple with progressive improvement in the cerebellar syndrome and walking over three months. Conclusion: Giant aneurysm of the PICA is rare. The localization in the posterior cerebral fossa can be confusing. Microsurgery gives a good result.展开更多
文摘The effect of low voltage and low concentration contrast agent on image quality of coronary CT angiography,radiation dose and iodine intake was evaluated.A total of 121 patients with body mass index(BMI)<26 kg/m2 and heart rate(HR)<70 beats/min were randomly divided into four groups:group A(n=31,80 kVp,270 mgl/mL);group B(n=33,100 kVp,270 mgl/mL);group C(h=30,100 kVp,320 mgl/mL);group D(w=27,100 kVp,400 mgl/mL).The automatic current modulation system and the iterative algorithm for reconstruction were adopted in each group.The CT values and SD values of the aortic root(AR),subcutaneous fat,left coronary artery opening(LCA),and right coronary artery opening(RCA)were measured in all groups,the signalto-noise ratio(SNR)and contrast noise ratio(CNR)were calculated,and effective radiation dose and iodine intake were recorded.The subjective assessment for image quality was performed by two physicians using a 4-point scale.The results were compared using the one-way ANOVA and rank sum tests.The image quality of the four groups met the clinical diagnostic requirements.The CT values of AR in groups A,B,C,and D were 537.6±71.4,447.2±81.9,445.2±64.9 and 518.5±94.9 Hu,respectively,with no significant difference between group A and group D,or between group B and group C,while CT values in groups B and C were significantly lower than those in groups A and D(P<0.05).In groups A,B,C,and D,the LCA SNR values were 22.7±9.1,23.3±9.1,23.3±7.7 and 26.6±8.9,and the RCA CNR values were 26.9±9.&28.5±11.4,27.7土&8 and 32」±10.6,respectively.The AR visual scores in groups A,B,C and D were 3.8±0.2,3.9±0.3,3.9±0.3 and 4.0±0.3,respectively.There were no significant differences in SNR,CNR and visual score among the four groups(P>0.05).The radiation doses in groups A,B,C and D were 2.6±1.4,3.6±1.&4.9±3.5 and 4.9±2.8 mSv,respectively.The radiation dose in group A was significantly less than that in the rest three groups(P<0.05).The iodine intakes in groups A,B,C and D were 14.9±1.5,15.0±1.5,17.7±2.0 and 18.1±2.5 g,respectively.There was no significant difference in the intake of iodine between groups C and D,or between groups A and B,while iodine intake in groups A and B were significantly reduced as compared with that in groups C and D(P<0.05).It was concluded that for patients with low BMI and controlled HR,compared to 100 kVp tube voltage combined with multiple concentration contrast agents,80 kVp combined with 270 mgl/mL contrast agent is enough to ensure the quality of the images,and can reduce the radiation dose significantly,while reducing the amount of iodine intake notably,thus reducing the incidence of adverse reaction.
基金Supported by a grant from the Science and Technology Plan of Sichuan Province(No.2021YFS0225)the Science and Technology Plan of Chengdu(No.2021-YF05-01507-SN).
文摘Objective This study aimed to explore the feasibility of enhancing image quality in computed tomography(CT) pulmonary angiography (CTPA) and reducing radiation dose using the nonlinear blending (NLB)technique of dual-energy CT.Methods A total of 61 patients scheduled for CTPA were enrolled, and 30 patients underwent dual-energyscanning. Nonlinear blending images (NLB group) and three groups of linear blending images (LB group,80 kV group, and 140 kV group) were reconstructed after scanning;31 patients underwent single-energyscanning (120 kV group). The CT values and standard deviations of the pulmonary trunk, left and rightpulmonary arteries, and ipsilateral back muscle at the bifurcation level of the left and right pulmonaryarteries were measured. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the fivegroups were calculated. The subjective image quality of the five groups was assessed. The radiation dosesof the dual- and single-energy groups were recorded and calculated.Results The CNR and SNR values of blood vessels in the NLB group were significantly higher than thosein the LB, 140 kV, and 80 kV groups (CNR of pulmonary artery trunk: t = 3.50, 4.06, 7.17, all P < 0.05;SNRof pulmonary trunk: t = 3.76, 4.71, 6.92, all P < 0.05). There were no statistical differences in the CNR andSNR values between the NLB group and 120 kV group (P > 0.05). The effective radiation dose of the dualenergygroup was lower than that of the single-energy group (t = –4.52, P < 0.05). The subjective scores ofimages in the NLB group were the highest (4.28 ± 0.74).Conclusion The NLB technique of dual-energy CT can improve the image quality of CTPA and reducethe radiation dose, providing more reliable imaging data for the clinical diagnosis of pulmonary embolism.
文摘Objective:To analyze the imaging effect and accuracy of 64-slice spiral CT in the diagnosis of coronary artery stenosis.Methods:30 patients with suspected coronary heart disease admitted to our hospital from March 2022 to March 2023 were selected.All patients underwent both 64-slice spiral CT and digital subtraction angiography(DSA).DSA is considered the gold standard for diagnosis,so it was used to analyze the diagnostic performance of 64-slice spiral CT.Results:(1)The diagnostic results of digital subtraction angiography and 64-slice spiral CT was analyzed and compared with each other.The 64-slice spiral CT had an accuracy of 96.67%(29/30),a sensitivity 96.55%(28/29),and a specificity of 100.00%(1/1)in diagnosing coronary artery stenosis.(2)There was no significant difference between 64-slice spiral CT and digital subtraction angiography in the positive detection rate of anterior descending artery lesion,the positive detection rate of left main lesion,the positive detection rate of left circumflex artery lesion and the positive detection rate of right coronary artery lesion(P>0.05).(3)There was no significant difference between 64-slice spiral CT examination and DSA examination in identifying mild stenosis,moderate stenosis,and severe stenosis of coronary arteries(P>0.05).Conclusion:64-slice spiral CT examination can accurately determine the degree of occlusion of coronary arteries,which allows for the accurate diagnosis of coronary artery stenosis.
基金Fund supported by the Clinical Research Supporting Fund of Chinese PLA General Hospital(2016FC-TSYS-1039)~~
文摘Objectives To investigate the morphologic characteristics of intramural hematoma(IMH)on CT angiography(CTA),and evaluate the possible correlation of serum C-reactive protein(CRP)with morphologic characteristics of IMH.Material and Methods Forty-two patients who were initially diagnosed as IMH by aortic CTA and also had serum CRP examination on the same day of CTA were enrolled in this retrospective study,including 30 males and 12 females,with the mean age of 61±14 years old.The volumetric CT data were retrospectively processed and analyzed on post-processing workstation.Based on the thickness of IMH and the length-area curve,the crosssectional area of true lumen and total vessel were measured,the hematoma-vessel ratio(HVR)was calculated.Imaging characteristics were compared between patients who had pathological elevated CRP(>0.8 mg/dl)and those did not.Spearman correlation analyses of CRP level and morphological characteristics of IMH were performed,and the receiver operating characteristic(ROC)curve was used to evaluate the diagnostic validity of CRP.Results Of all 42 IMH patients,the mean serum CRP was 3.94±4.71 mg/dl,and the mean HVR was 46.7%±14.2%.HVR in patients with elevated CRP was significantly higher than those with normal CRP(49.7%±15.0%vs.40.7%±10.5%,P=0.030).HVR was mildly correlated with CRP in all patients(r=0.48,P<0.001).CRP levels differed neither between patients with Stanford type A and B(P=0.207),nor between patients with and without intimal disruption(P=0.230).To discriminate HVR>47%(the mean value),the area under curve(AUC)were 0.700(95%CI:0.535-0.865)for CRP at a cutoff point of 3.55 mg/dl,with a sensitivity of 54.5%and a specificity of 90.0%.Conclusion CRP was mildly correlated with the severity of cross-sectional hematoma area of IMH,but not with Stanford types and the presence of intimal disruption.
基金supported by Research Project of Third Military Medical University(2016YLC22)
文摘Objective: To identify the morphological parameters that are related to intracranial aneurysms(IAs) rupture using a case-control model.Methods: A total of 107 patients with multiple IAs and aneurysmal subarachnoid hemorrhage between August 2011 and February 2017 were enrolled in this study.Characteristics of IAs location, shape, neck width, perpendicular height, depth, maximum size, flow angle, parent vessel diameter(PVD), aspect ratio(AR) and size ratio(SR) were evaluated using CT angiography.Multiple logistic regression analysis was used to identify the independent risk factors associated with IAs rupture.Receiver operating characteristic curve analysis was performed on the final model, and the optimal thresholds were obtained.Results: IAs located in the internal carotid artery(ICA) was associated with a negative risk of rupture, whereas AR, SR1(height/PVD) and SR2(depth/PVD) were associated with increased risk of rupture.When SR was calculated differently, the odds ratio values of these factors were also different.The receiver operating characteristic curve showed that AR, SR1 and SR2 had cut-off values of 1.01, 1.48 and 1.40, respectively.SR3(maximum size/PVD) was not associated with IAs rupture.Conclusions: IAs located in the ICA are associated with a negative risk of rupture, while high AR(>1.01), SR1(>1.48) or SR2(>1.40) are risk factors for multiple IAs rupture.
文摘BACKGROUND:This study was undertaken to identify the prevalence of pulmonary embolism(PE) in the emergency department(ED) of an urban teaching hospital and also to test a Bayesian model in estimating the number of CT pulmonary angiography(CTA) expected to be performed in an emergency department.METHODS:The data for this study was obtained through a retrospective review of electronic medical records for all ED patients suspected of PE who underwent chest CTA or ventilation perfusion scanning(V/Q) between 2009 and 2010.The data is presented as means and standard deviation for continuous variables and percentages with 95%confidence intervals(95%CI) for proportions.The prevalence of PE was used as pre-test probability in the Bayesian model.Post-test probability was obtained using a Fagan nomogram and likelihood ratios for CTA.RESULTS:A total of 778 patients(560 females) with mean age of 50 years(range 18-98 years)were enrolled(98.3%underwent chest CTA and 1.7%underwent V/Q scan).A total of 69 patients had PE,rendering an overall prevalence of 8.9%(95%CI,7.1%to 11.1%) for PE.We calculated that132 CTA's per year could be avoided in our institution,without compromising safe exclusions of PE(keeping post-test probability of PE below 2%).CONCLUSIONS:Despite differences in our patient populations and /or study designs,the prevalence of PE in our institution is about average compared to other institutions.Our proposed model for calculating redundant chest CTA is simple and can be used by institutions to identify overuse of CTA.
文摘Basilar artery fenestration is a rare anatomical variation resulting from the failed fusion of the two vertebral arteries during embryonic life. In order of frequency, it is the second most common location of vascular fenestrations after the anterior communicating artery. Vertebrobasilar junction aneurysms are uncommon but often associated with basilar artery fenestration. We report the case of a fenestrated vertebrobasilar junction saccular aneurysm in a 57-year-old woman. The diagnosis was incidentally made on CT angiography which found the anatomical variant and the aneurysm. The radiological features illustrating this association are detailed here and a brief discussion of its pathogenesis and management was made. Vertebrobasilar junction aneurysms are rare and their presence should suggest an associated basilar fenestration.
文摘Introduction: Rupture of intracranial aneurisms leads to severe morbidity and mortality. There are two modalities of treatment surgery and endovascular treatment. The diagnosis is made by angiography (DSA, CTA, RMA). The angiographic features used to assess the risk of the complications and choose the treatment modality are size, location and aneurism morphology. Materials and Methods: We reviewed and analyzed the computed tomographic angiography and magnetic resonance angiography of all patients admitted to the hospital of Mali with IAs from 2015 to 2021 either 7 years. Patients who were less than 18 years old, those with non-aneurysmal SAH, patients who request a discharge and those with an incomplete angiographic description of the IAs were excluded from the analysis. Results: We have collected 105 patients with 109 aneurysms. The sex ratio was 2/1 in favor of females. The mean age was 44.51 years with the range from 18 to 70 years. The presentation mode was subarachnoid hemorrhage (SAH) in 97% of cases. 76.19% had confirmed high blood pressure before the bleeding. 19.04% were diabetics. 98% of our patients have made a CT angiography and 2% have made MR angiography for the aneurysm diagnosis. 97.24% of aneurisms were located in the anterior part of the Willis circle. 39.44% of these aneurisms were the anterior communicating complex aneurysm. 27.52% of aneurysm had a small size, 42.20% had a medium size, 20.18% large size against 5.50% of the giant (Figure 3) and the middle cerebral artery was the most involved in the least. 95.41% of cases were saccular aneurysms against 4.59% fusiform. Conclusion: The angiographic feature of an intracranial aneurism in the Malian population may differ from other populations of the sub-region. The anterior communicating complex aneurysm is more common and the aneurism of the posterior part of the Willis circle is less common. We found the aneurism size ≥ 6 mm, ACA, MCA and Pcom more frequent.
文摘Context: Cerebellar syndrome caused by disturbances of balance and coordination is not an uncommon neurological disorder. It has varied etiologies usually caused by tumor processes or suppurative collections. Vascular causes remain very rare, especially when it is a giant aneurysm of PICA representing 1% of intracranial aneurysms. Treating giant PICA aneurysms is a very difficult task for neurosurgeons because the surgical dissection can lead to severe damage due to the intimate relationship of PICA with the brainstem or nerve structures. We report a case of giant PICA aneurysm responsible for cerebellar syndrome successfully treated with surgery. The objective of this work is to draw the attention of practitioners to this unusual cause which can lead to diagnosis wandering and a lack of planning at the time of management. Case report: A 65 years old hypertensive patient was seen for a progressive disturbance of balance and walking disorder, but worsened in the last three months with no notion of fever. On admission, the patient was lucid, oriented in time and space and presented with static and kinetic cerebellar syndrome. Brain CT-scan without and with contrast revealed a tissular mass in the posterior fossa suggesting a tumor process, however, CT angiography showed a giant aneurysm of the PICA after reconstruction. A careful microdissection by a sub-occipital approach was decided. Opening the large cistern made it possible to visualize the aneurysm sack surrounded by a yellowish gliosis. The reclining and microdissection revealed the neck of the aneurysm, which was clipped to exclude the giant aneurysm in block. Postoperative follow-up was simple with progressive improvement in the cerebellar syndrome and walking over three months. Conclusion: Giant aneurysm of the PICA is rare. The localization in the posterior cerebral fossa can be confusing. Microsurgery gives a good result.
