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Kazuhiro Yoshioka - One of the best experts on this subject based on the ideXlab platform.

  • o 012 utilization of blood sampling global Oxygen extraction fraction to anticipate cerebral hyperfusion syndrome following elective carotid artery stenting
    Journal of NeuroInterventional Surgery, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Shigen Kasakura, Y Tannoo, Kazuhiro Yoshioka
    Abstract:

    Background It is required to anticipate cerebral hyperperfusion syndrome (CHS) following elective carotid artery stenting (eCAS). Purpose The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) had relation to CHS following eCAS. Methods Included in our analysis were patients (1) who underwent eCAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation just before and immediately after eCAS, and (3) who underwent SPECT before and just after eCAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as restlessness or altered level of conscious in addition to classical triad of headache, seizure or neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after eCAS. CBF increase in the eCAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CBF in the CAS-sided MCA territory divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and the incidence of CHS. Results Median pre-CAS OEF and post-CAS OEF were 0.41 and 0.42, respectively. Nine patients presented CHS. Scattergrams of the two groups with CHS and without CHS showed that the cut-off values of the pre-CAS OEF, the post-CAS OEF, the pre-CAS CBF ratio and the increase of CBF ratio to anticipate CHS were more than 0.46 (p Conclusion Elevation of blood sampling pre-CAS or post-CAS OEF can anticipate CHS following eCAS. Disclosures T. Mori: 2; C; Kaneka Medix. 6; C; Medikit. T. Iwata: None. Y. Tannoo: None. S. Kasakura: None. K. Yoshioka: None.

  • abstract t p103 global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion syndrome following carotid artery stenting
    Stroke, 2015
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: Cerebral hyperperfusion syndrome (CHS) sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. The incidence of CHS following carotid revascularization is not high. However, once it occurs, it may result in disabled clinical outcome. Therefore, it is very important to anticipate CHS. To anticipate CHS, single-photon emission computed tomography (SPECT) or PET may be useful, but it is impractical for all patients. Purpose: The purpose of our study was to investigate whether or not global Oxygen extraction fraction (OEF) by blood sampling anticipated CHS following carotid artery stenting (CAS). Methods: When patients underwent elective CAS from September 2010 to June 2014, we performed blood sampling for OEF calculation before and immediately after elective CAS. Elective CAS was defined as CAS in asymptomatic patients or CAS in patients who experienced a last ischemic attack 30 days or more previously. Data were collected prospectively. OEF was calculated from Arteriovenous Oxygen Difference as follows: OEF = (Ca02-Cv02)/Ca02 where Ca02 is arterial Oxygen content and CvO2 is the jugular vein Oxygen content. We evaluated baseline features of patients, pre-CAS OEF, post-CAS OEF and the occurrence of CHS. Results: In overall 131 patients, the median pre-CAS OEF was 0.41 (0.37-0.46; IQR), and median post-CAS OEF was 0.42 (0.38-0.47; IQR). Seven patients presented CHS. Between the two groups with and without CHS, there were no Differences in patient characteristics. Between the two groups, there were not statistically significant Differences of pre-CAS OEF (0.47 vs 0.41). However, patients in CHS group had higher post-CAS OEF than patients in non_CHS group (0.51 vs 0.42) (Mann-Whitney’s U test, p Conclusion: Elevation of blood sampling OEF immediately after CAS anticipated post-CAS CHS.

  • abstract w p115 utilization of blood sampling global Oxygen extraction fraction and spect to anticipate cerebral hyperperfusion syndrome following elective carotid artery stenting
    Stroke, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: It is required to anticipate cerebral hyperperfusion syndrome (CHS) following carotid artery stenting (CAS). Purpose: The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) and post-CAS CBF increase in SPECT had relation to CHS following CAS. Methods: Included in our analysis were patients (1) who underwent elective CAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation before and immediately after CAS, and (3) who underwent SPECT before and just after CAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as pulsatile headaches, restlessness, convulsion, and/or new neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after CAS. CBF increase in the CAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CAS-sided fronto-parietal CBF divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and CHS. Results: During the study period, 134 patients matched our criteria for analysis. Pre-CAS OEF was 0.41+-0.06, post-CAS OEF was 0.42+-0.08, pre-CAS CBF ratio: 88.7+-15.4%, CBF increase: 1.86+-12.3%. Nine patients presented CHS. Among them, pre-CAS OEF, CBF ratio and CBF increase were significant. ROC curves showed that pre-CAS OEF of 0.46 (p Conclusion: Elevation of pre-CAS OEF and increase of post-CAS CBF were strongly related to CHS.

Tomonori Iwata - One of the best experts on this subject based on the ideXlab platform.

  • o 012 utilization of blood sampling global Oxygen extraction fraction to anticipate cerebral hyperfusion syndrome following elective carotid artery stenting
    Journal of NeuroInterventional Surgery, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Shigen Kasakura, Y Tannoo, Kazuhiro Yoshioka
    Abstract:

    Background It is required to anticipate cerebral hyperperfusion syndrome (CHS) following elective carotid artery stenting (eCAS). Purpose The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) had relation to CHS following eCAS. Methods Included in our analysis were patients (1) who underwent eCAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation just before and immediately after eCAS, and (3) who underwent SPECT before and just after eCAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as restlessness or altered level of conscious in addition to classical triad of headache, seizure or neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after eCAS. CBF increase in the eCAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CBF in the CAS-sided MCA territory divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and the incidence of CHS. Results Median pre-CAS OEF and post-CAS OEF were 0.41 and 0.42, respectively. Nine patients presented CHS. Scattergrams of the two groups with CHS and without CHS showed that the cut-off values of the pre-CAS OEF, the post-CAS OEF, the pre-CAS CBF ratio and the increase of CBF ratio to anticipate CHS were more than 0.46 (p Conclusion Elevation of blood sampling pre-CAS or post-CAS OEF can anticipate CHS following eCAS. Disclosures T. Mori: 2; C; Kaneka Medix. 6; C; Medikit. T. Iwata: None. Y. Tannoo: None. S. Kasakura: None. K. Yoshioka: None.

  • abstract t p103 global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion syndrome following carotid artery stenting
    Stroke, 2015
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: Cerebral hyperperfusion syndrome (CHS) sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. The incidence of CHS following carotid revascularization is not high. However, once it occurs, it may result in disabled clinical outcome. Therefore, it is very important to anticipate CHS. To anticipate CHS, single-photon emission computed tomography (SPECT) or PET may be useful, but it is impractical for all patients. Purpose: The purpose of our study was to investigate whether or not global Oxygen extraction fraction (OEF) by blood sampling anticipated CHS following carotid artery stenting (CAS). Methods: When patients underwent elective CAS from September 2010 to June 2014, we performed blood sampling for OEF calculation before and immediately after elective CAS. Elective CAS was defined as CAS in asymptomatic patients or CAS in patients who experienced a last ischemic attack 30 days or more previously. Data were collected prospectively. OEF was calculated from Arteriovenous Oxygen Difference as follows: OEF = (Ca02-Cv02)/Ca02 where Ca02 is arterial Oxygen content and CvO2 is the jugular vein Oxygen content. We evaluated baseline features of patients, pre-CAS OEF, post-CAS OEF and the occurrence of CHS. Results: In overall 131 patients, the median pre-CAS OEF was 0.41 (0.37-0.46; IQR), and median post-CAS OEF was 0.42 (0.38-0.47; IQR). Seven patients presented CHS. Between the two groups with and without CHS, there were no Differences in patient characteristics. Between the two groups, there were not statistically significant Differences of pre-CAS OEF (0.47 vs 0.41). However, patients in CHS group had higher post-CAS OEF than patients in non_CHS group (0.51 vs 0.42) (Mann-Whitney’s U test, p Conclusion: Elevation of blood sampling OEF immediately after CAS anticipated post-CAS CHS.

  • abstract w p115 utilization of blood sampling global Oxygen extraction fraction and spect to anticipate cerebral hyperperfusion syndrome following elective carotid artery stenting
    Stroke, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: It is required to anticipate cerebral hyperperfusion syndrome (CHS) following carotid artery stenting (CAS). Purpose: The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) and post-CAS CBF increase in SPECT had relation to CHS following CAS. Methods: Included in our analysis were patients (1) who underwent elective CAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation before and immediately after CAS, and (3) who underwent SPECT before and just after CAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as pulsatile headaches, restlessness, convulsion, and/or new neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after CAS. CBF increase in the CAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CAS-sided fronto-parietal CBF divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and CHS. Results: During the study period, 134 patients matched our criteria for analysis. Pre-CAS OEF was 0.41+-0.06, post-CAS OEF was 0.42+-0.08, pre-CAS CBF ratio: 88.7+-15.4%, CBF increase: 1.86+-12.3%. Nine patients presented CHS. Among them, pre-CAS OEF, CBF ratio and CBF increase were significant. ROC curves showed that pre-CAS OEF of 0.46 (p Conclusion: Elevation of pre-CAS OEF and increase of post-CAS CBF were strongly related to CHS.

  • global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion phenomenon after carotid artery stenting
    Neurosurgery, 2014
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yuichi Miyazaki, Yoshinori Aoyagi
    Abstract:

    BACKGROUND: Cerebral hyperperfusion syndrome sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. To prevent cerebral hyperperfusion syndrome, cerebral hyperperfusion phenomenon (CHP) must be detected early. Single-photon emission computed tomography (SPECT) is useful for detecting CHP, but it is impractical on a daily basis. A tool with high availability to find CHP is desired. OBJECTIVE: To investigate whether global Oxygen extraction fraction (OEF) by a blood sampling method is useful for indicating CHP after carotid artery stenting (CAS). METHODS: When patients underwent elective CAS from September 2010 to August 2012, we performed blood sampling for OEF calculation and SPECT before and immediately after elective CAS. Data were collected prospectively. OEF was calculated from the cerebral Arteriovenous Oxygen Difference. Cerebral blood flow was measured in the affected middle cerebral artery (MCA) territory and in the ipsilateral cerebellum by SPECT. The ratio of MCA to cerebellar activity was defined as cerebral blood flow in the affected MCA territory divided by cerebral blood flow in the ipsilateral cerebellar hemisphere. Probable CHP was defined as ≥10% increase in the ratio of MCA to cerebellar activity after CAS. The relationship between peri-CAS OEF and probable CHP was evaluated. RESULTS: Of the 96 patients enrolled, 92 patients were analyzed. Probable CHP occurred in 17 patients. Post-CAS OEF was related to probable CHP (P < .01), but pre-CAS OEF was not. The receiver-operating characteristic curve showed that the cutoff value was 45% for probable CHP (P < .001). CONCLUSION: An increase in blood sampling OEF immediately after CAS was related to probable CHP; then the Oxygen demand should be reduced.

  • abstract wp128 blood sampling Oxygen extraction fraction as predictors of hyperperfusion phenomenon following carotid artery stenting
    Stroke, 2013
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yoichiro Takahashi, Yuichi Miyazaki, M Nakazaki, Koji Mizokami
    Abstract:

    Backgrounds and Purpose: Hyperperfusion syndrome following carotid artery stenting (CAS) may occur in patients suffering from stage 2 hemodynamic failure, where Oxygen extraction fraction is elevated. The purpose of our retrospective study was to investigate whether or not blood sampling OEF has some relation to hyperperfusion phenomenon (HP) following CAS. Materials and Methods: Included for analysis were patients (1) who were admitted to our institution from 2010 to 2012, (2) who underwent elective CAS and (3) who underwent blood sampling for OEF calculation and single-photon emission computed tomography (SPECT) before and immediately after CAS. Oxygen extraction fraction (OEF) was calculated from Arteriovenous Oxygen Difference as follows: OEF = (Ca02-Cv02) / Ca02 where Ca02 is arterial Oxygen content and CvO2 is the jugular vein Oxygen content. Cerebral blood flow (CBF) was measured in bilateral middle cerebral artery (MCA) territory and in the affected side cerebellar hemisphere by SPECT. Asymmetry index (AI) was defined as CBF in the affected side / CBF in the unaffected side, and MCA-to-cerebellar activity ratio as the CBF in the affected side / the CBF in the ipsilateral cerebellar hemisphere. HP was defined as 10% or more of increase in MCA-to-cerebellar activity ratio following CAS. Results: During the study period, 90 patients matched our criteria for retrospective analysis and 21 patients presented post-CAS HP. Procedures were successful in every case. There was no relation of pre-CAS OEF to asymmetry index and MCA-to-cerebellar activity ratio. There was no relation of post-CAS OEF to asymmetry index, but post-CAS OEF had relation to MCA-to-cerebellar activity ratio (r=0.26, p Conclusion: Elevation of blood sampling OEF immediately after CAS is related to post-CAS HP.

Takahisa Mori - One of the best experts on this subject based on the ideXlab platform.

  • o 012 utilization of blood sampling global Oxygen extraction fraction to anticipate cerebral hyperfusion syndrome following elective carotid artery stenting
    Journal of NeuroInterventional Surgery, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Shigen Kasakura, Y Tannoo, Kazuhiro Yoshioka
    Abstract:

    Background It is required to anticipate cerebral hyperperfusion syndrome (CHS) following elective carotid artery stenting (eCAS). Purpose The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) had relation to CHS following eCAS. Methods Included in our analysis were patients (1) who underwent eCAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation just before and immediately after eCAS, and (3) who underwent SPECT before and just after eCAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as restlessness or altered level of conscious in addition to classical triad of headache, seizure or neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after eCAS. CBF increase in the eCAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CBF in the CAS-sided MCA territory divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and the incidence of CHS. Results Median pre-CAS OEF and post-CAS OEF were 0.41 and 0.42, respectively. Nine patients presented CHS. Scattergrams of the two groups with CHS and without CHS showed that the cut-off values of the pre-CAS OEF, the post-CAS OEF, the pre-CAS CBF ratio and the increase of CBF ratio to anticipate CHS were more than 0.46 (p Conclusion Elevation of blood sampling pre-CAS or post-CAS OEF can anticipate CHS following eCAS. Disclosures T. Mori: 2; C; Kaneka Medix. 6; C; Medikit. T. Iwata: None. Y. Tannoo: None. S. Kasakura: None. K. Yoshioka: None.

  • abstract t p103 global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion syndrome following carotid artery stenting
    Stroke, 2015
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: Cerebral hyperperfusion syndrome (CHS) sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. The incidence of CHS following carotid revascularization is not high. However, once it occurs, it may result in disabled clinical outcome. Therefore, it is very important to anticipate CHS. To anticipate CHS, single-photon emission computed tomography (SPECT) or PET may be useful, but it is impractical for all patients. Purpose: The purpose of our study was to investigate whether or not global Oxygen extraction fraction (OEF) by blood sampling anticipated CHS following carotid artery stenting (CAS). Methods: When patients underwent elective CAS from September 2010 to June 2014, we performed blood sampling for OEF calculation before and immediately after elective CAS. Elective CAS was defined as CAS in asymptomatic patients or CAS in patients who experienced a last ischemic attack 30 days or more previously. Data were collected prospectively. OEF was calculated from Arteriovenous Oxygen Difference as follows: OEF = (Ca02-Cv02)/Ca02 where Ca02 is arterial Oxygen content and CvO2 is the jugular vein Oxygen content. We evaluated baseline features of patients, pre-CAS OEF, post-CAS OEF and the occurrence of CHS. Results: In overall 131 patients, the median pre-CAS OEF was 0.41 (0.37-0.46; IQR), and median post-CAS OEF was 0.42 (0.38-0.47; IQR). Seven patients presented CHS. Between the two groups with and without CHS, there were no Differences in patient characteristics. Between the two groups, there were not statistically significant Differences of pre-CAS OEF (0.47 vs 0.41). However, patients in CHS group had higher post-CAS OEF than patients in non_CHS group (0.51 vs 0.42) (Mann-Whitney’s U test, p Conclusion: Elevation of blood sampling OEF immediately after CAS anticipated post-CAS CHS.

  • abstract w p115 utilization of blood sampling global Oxygen extraction fraction and spect to anticipate cerebral hyperperfusion syndrome following elective carotid artery stenting
    Stroke, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: It is required to anticipate cerebral hyperperfusion syndrome (CHS) following carotid artery stenting (CAS). Purpose: The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) and post-CAS CBF increase in SPECT had relation to CHS following CAS. Methods: Included in our analysis were patients (1) who underwent elective CAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation before and immediately after CAS, and (3) who underwent SPECT before and just after CAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as pulsatile headaches, restlessness, convulsion, and/or new neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after CAS. CBF increase in the CAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CAS-sided fronto-parietal CBF divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and CHS. Results: During the study period, 134 patients matched our criteria for analysis. Pre-CAS OEF was 0.41+-0.06, post-CAS OEF was 0.42+-0.08, pre-CAS CBF ratio: 88.7+-15.4%, CBF increase: 1.86+-12.3%. Nine patients presented CHS. Among them, pre-CAS OEF, CBF ratio and CBF increase were significant. ROC curves showed that pre-CAS OEF of 0.46 (p Conclusion: Elevation of pre-CAS OEF and increase of post-CAS CBF were strongly related to CHS.

  • global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion phenomenon after carotid artery stenting
    Neurosurgery, 2014
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yuichi Miyazaki, Yoshinori Aoyagi
    Abstract:

    BACKGROUND: Cerebral hyperperfusion syndrome sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. To prevent cerebral hyperperfusion syndrome, cerebral hyperperfusion phenomenon (CHP) must be detected early. Single-photon emission computed tomography (SPECT) is useful for detecting CHP, but it is impractical on a daily basis. A tool with high availability to find CHP is desired. OBJECTIVE: To investigate whether global Oxygen extraction fraction (OEF) by a blood sampling method is useful for indicating CHP after carotid artery stenting (CAS). METHODS: When patients underwent elective CAS from September 2010 to August 2012, we performed blood sampling for OEF calculation and SPECT before and immediately after elective CAS. Data were collected prospectively. OEF was calculated from the cerebral Arteriovenous Oxygen Difference. Cerebral blood flow was measured in the affected middle cerebral artery (MCA) territory and in the ipsilateral cerebellum by SPECT. The ratio of MCA to cerebellar activity was defined as cerebral blood flow in the affected MCA territory divided by cerebral blood flow in the ipsilateral cerebellar hemisphere. Probable CHP was defined as ≥10% increase in the ratio of MCA to cerebellar activity after CAS. The relationship between peri-CAS OEF and probable CHP was evaluated. RESULTS: Of the 96 patients enrolled, 92 patients were analyzed. Probable CHP occurred in 17 patients. Post-CAS OEF was related to probable CHP (P < .01), but pre-CAS OEF was not. The receiver-operating characteristic curve showed that the cutoff value was 45% for probable CHP (P < .001). CONCLUSION: An increase in blood sampling OEF immediately after CAS was related to probable CHP; then the Oxygen demand should be reduced.

  • abstract wp128 blood sampling Oxygen extraction fraction as predictors of hyperperfusion phenomenon following carotid artery stenting
    Stroke, 2013
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yoichiro Takahashi, Yuichi Miyazaki, M Nakazaki, Koji Mizokami
    Abstract:

    Backgrounds and Purpose: Hyperperfusion syndrome following carotid artery stenting (CAS) may occur in patients suffering from stage 2 hemodynamic failure, where Oxygen extraction fraction is elevated. The purpose of our retrospective study was to investigate whether or not blood sampling OEF has some relation to hyperperfusion phenomenon (HP) following CAS. Materials and Methods: Included for analysis were patients (1) who were admitted to our institution from 2010 to 2012, (2) who underwent elective CAS and (3) who underwent blood sampling for OEF calculation and single-photon emission computed tomography (SPECT) before and immediately after CAS. Oxygen extraction fraction (OEF) was calculated from Arteriovenous Oxygen Difference as follows: OEF = (Ca02-Cv02) / Ca02 where Ca02 is arterial Oxygen content and CvO2 is the jugular vein Oxygen content. Cerebral blood flow (CBF) was measured in bilateral middle cerebral artery (MCA) territory and in the affected side cerebellar hemisphere by SPECT. Asymmetry index (AI) was defined as CBF in the affected side / CBF in the unaffected side, and MCA-to-cerebellar activity ratio as the CBF in the affected side / the CBF in the ipsilateral cerebellar hemisphere. HP was defined as 10% or more of increase in MCA-to-cerebellar activity ratio following CAS. Results: During the study period, 90 patients matched our criteria for retrospective analysis and 21 patients presented post-CAS HP. Procedures were successful in every case. There was no relation of pre-CAS OEF to asymmetry index and MCA-to-cerebellar activity ratio. There was no relation of post-CAS OEF to asymmetry index, but post-CAS OEF had relation to MCA-to-cerebellar activity ratio (r=0.26, p Conclusion: Elevation of blood sampling OEF immediately after CAS is related to post-CAS HP.

Yoshinori Aoyagi - One of the best experts on this subject based on the ideXlab platform.

  • abstract w p115 utilization of blood sampling global Oxygen extraction fraction and spect to anticipate cerebral hyperperfusion syndrome following elective carotid artery stenting
    Stroke, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: It is required to anticipate cerebral hyperperfusion syndrome (CHS) following carotid artery stenting (CAS). Purpose: The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) and post-CAS CBF increase in SPECT had relation to CHS following CAS. Methods: Included in our analysis were patients (1) who underwent elective CAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation before and immediately after CAS, and (3) who underwent SPECT before and just after CAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as pulsatile headaches, restlessness, convulsion, and/or new neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after CAS. CBF increase in the CAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CAS-sided fronto-parietal CBF divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and CHS. Results: During the study period, 134 patients matched our criteria for analysis. Pre-CAS OEF was 0.41+-0.06, post-CAS OEF was 0.42+-0.08, pre-CAS CBF ratio: 88.7+-15.4%, CBF increase: 1.86+-12.3%. Nine patients presented CHS. Among them, pre-CAS OEF, CBF ratio and CBF increase were significant. ROC curves showed that pre-CAS OEF of 0.46 (p Conclusion: Elevation of pre-CAS OEF and increase of post-CAS CBF were strongly related to CHS.

  • abstract t p103 global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion syndrome following carotid artery stenting
    Stroke, 2015
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: Cerebral hyperperfusion syndrome (CHS) sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. The incidence of CHS following carotid revascularization is not high. However, once it occurs, it may result in disabled clinical outcome. Therefore, it is very important to anticipate CHS. To anticipate CHS, single-photon emission computed tomography (SPECT) or PET may be useful, but it is impractical for all patients. Purpose: The purpose of our study was to investigate whether or not global Oxygen extraction fraction (OEF) by blood sampling anticipated CHS following carotid artery stenting (CAS). Methods: When patients underwent elective CAS from September 2010 to June 2014, we performed blood sampling for OEF calculation before and immediately after elective CAS. Elective CAS was defined as CAS in asymptomatic patients or CAS in patients who experienced a last ischemic attack 30 days or more previously. Data were collected prospectively. OEF was calculated from Arteriovenous Oxygen Difference as follows: OEF = (Ca02-Cv02)/Ca02 where Ca02 is arterial Oxygen content and CvO2 is the jugular vein Oxygen content. We evaluated baseline features of patients, pre-CAS OEF, post-CAS OEF and the occurrence of CHS. Results: In overall 131 patients, the median pre-CAS OEF was 0.41 (0.37-0.46; IQR), and median post-CAS OEF was 0.42 (0.38-0.47; IQR). Seven patients presented CHS. Between the two groups with and without CHS, there were no Differences in patient characteristics. Between the two groups, there were not statistically significant Differences of pre-CAS OEF (0.47 vs 0.41). However, patients in CHS group had higher post-CAS OEF than patients in non_CHS group (0.51 vs 0.42) (Mann-Whitney’s U test, p Conclusion: Elevation of blood sampling OEF immediately after CAS anticipated post-CAS CHS.

  • global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion phenomenon after carotid artery stenting
    Neurosurgery, 2014
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yuichi Miyazaki, Yoshinori Aoyagi
    Abstract:

    BACKGROUND: Cerebral hyperperfusion syndrome sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. To prevent cerebral hyperperfusion syndrome, cerebral hyperperfusion phenomenon (CHP) must be detected early. Single-photon emission computed tomography (SPECT) is useful for detecting CHP, but it is impractical on a daily basis. A tool with high availability to find CHP is desired. OBJECTIVE: To investigate whether global Oxygen extraction fraction (OEF) by a blood sampling method is useful for indicating CHP after carotid artery stenting (CAS). METHODS: When patients underwent elective CAS from September 2010 to August 2012, we performed blood sampling for OEF calculation and SPECT before and immediately after elective CAS. Data were collected prospectively. OEF was calculated from the cerebral Arteriovenous Oxygen Difference. Cerebral blood flow was measured in the affected middle cerebral artery (MCA) territory and in the ipsilateral cerebellum by SPECT. The ratio of MCA to cerebellar activity was defined as cerebral blood flow in the affected MCA territory divided by cerebral blood flow in the ipsilateral cerebellar hemisphere. Probable CHP was defined as ≥10% increase in the ratio of MCA to cerebellar activity after CAS. The relationship between peri-CAS OEF and probable CHP was evaluated. RESULTS: Of the 96 patients enrolled, 92 patients were analyzed. Probable CHP occurred in 17 patients. Post-CAS OEF was related to probable CHP (P < .01), but pre-CAS OEF was not. The receiver-operating characteristic curve showed that the cutoff value was 45% for probable CHP (P < .001). CONCLUSION: An increase in blood sampling OEF immediately after CAS was related to probable CHP; then the Oxygen demand should be reduced.

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  • o 012 utilization of blood sampling global Oxygen extraction fraction to anticipate cerebral hyperfusion syndrome following elective carotid artery stenting
    Journal of NeuroInterventional Surgery, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Shigen Kasakura, Y Tannoo, Kazuhiro Yoshioka
    Abstract:

    Background It is required to anticipate cerebral hyperperfusion syndrome (CHS) following elective carotid artery stenting (eCAS). Purpose The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) had relation to CHS following eCAS. Methods Included in our analysis were patients (1) who underwent eCAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation just before and immediately after eCAS, and (3) who underwent SPECT before and just after eCAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as restlessness or altered level of conscious in addition to classical triad of headache, seizure or neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after eCAS. CBF increase in the eCAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CBF in the CAS-sided MCA territory divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and the incidence of CHS. Results Median pre-CAS OEF and post-CAS OEF were 0.41 and 0.42, respectively. Nine patients presented CHS. Scattergrams of the two groups with CHS and without CHS showed that the cut-off values of the pre-CAS OEF, the post-CAS OEF, the pre-CAS CBF ratio and the increase of CBF ratio to anticipate CHS were more than 0.46 (p Conclusion Elevation of blood sampling pre-CAS or post-CAS OEF can anticipate CHS following eCAS. Disclosures T. Mori: 2; C; Kaneka Medix. 6; C; Medikit. T. Iwata: None. Y. Tannoo: None. S. Kasakura: None. K. Yoshioka: None.

  • abstract t p103 global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion syndrome following carotid artery stenting
    Stroke, 2015
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: Cerebral hyperperfusion syndrome (CHS) sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. The incidence of CHS following carotid revascularization is not high. However, once it occurs, it may result in disabled clinical outcome. Therefore, it is very important to anticipate CHS. To anticipate CHS, single-photon emission computed tomography (SPECT) or PET may be useful, but it is impractical for all patients. Purpose: The purpose of our study was to investigate whether or not global Oxygen extraction fraction (OEF) by blood sampling anticipated CHS following carotid artery stenting (CAS). Methods: When patients underwent elective CAS from September 2010 to June 2014, we performed blood sampling for OEF calculation before and immediately after elective CAS. Elective CAS was defined as CAS in asymptomatic patients or CAS in patients who experienced a last ischemic attack 30 days or more previously. Data were collected prospectively. OEF was calculated from Arteriovenous Oxygen Difference as follows: OEF = (Ca02-Cv02)/Ca02 where Ca02 is arterial Oxygen content and CvO2 is the jugular vein Oxygen content. We evaluated baseline features of patients, pre-CAS OEF, post-CAS OEF and the occurrence of CHS. Results: In overall 131 patients, the median pre-CAS OEF was 0.41 (0.37-0.46; IQR), and median post-CAS OEF was 0.42 (0.38-0.47; IQR). Seven patients presented CHS. Between the two groups with and without CHS, there were no Differences in patient characteristics. Between the two groups, there were not statistically significant Differences of pre-CAS OEF (0.47 vs 0.41). However, patients in CHS group had higher post-CAS OEF than patients in non_CHS group (0.51 vs 0.42) (Mann-Whitney’s U test, p Conclusion: Elevation of blood sampling OEF immediately after CAS anticipated post-CAS CHS.

  • abstract w p115 utilization of blood sampling global Oxygen extraction fraction and spect to anticipate cerebral hyperperfusion syndrome following elective carotid artery stenting
    Stroke, 2015
    Co-Authors: Takahisa Mori, Tomonori Iwata, Yuhei Tanno, Shigen Kasakura, Yoshinori Aoyagi, Kazuhiro Yoshioka
    Abstract:

    Background: It is required to anticipate cerebral hyperperfusion syndrome (CHS) following carotid artery stenting (CAS). Purpose: The purpose of our retrospective study was to investigate whether or not blood sampling Oxygen extraction fraction (OEF) and post-CAS CBF increase in SPECT had relation to CHS following CAS. Methods: Included in our analysis were patients (1) who underwent elective CAS in our institution between October 2010 and May 2014, and (2) who underwent blood sampling for OEF calculation before and immediately after CAS, and (3) who underwent SPECT before and just after CAS. OEF was calculated from cerebral Arteriovenous Oxygen Difference. Arterial blood was sampled from the common carotid artery and venous blood from the dominant-sided superior jugular bulb. CHS was defined as pulsatile headaches, restlessness, convulsion, and/or new neurological symptoms not due to cerebral ischemia within seven days following CAS. CBF was measured before and just after CAS. CBF increase in the CAS side was defined as follows; (post-CAS CBF ratio - pre-CAS CBF ratio) of more than 10%, where CBF ratio was defined as CAS-sided fronto-parietal CBF divided by ipsilateral cerebellar CBF (%). Evaluated were baseline features in patients, pre-CAS OEF, post-CAS OEF, CBF ratio, CBF increase and CHS. Results: During the study period, 134 patients matched our criteria for analysis. Pre-CAS OEF was 0.41+-0.06, post-CAS OEF was 0.42+-0.08, pre-CAS CBF ratio: 88.7+-15.4%, CBF increase: 1.86+-12.3%. Nine patients presented CHS. Among them, pre-CAS OEF, CBF ratio and CBF increase were significant. ROC curves showed that pre-CAS OEF of 0.46 (p Conclusion: Elevation of pre-CAS OEF and increase of post-CAS CBF were strongly related to CHS.

  • global Oxygen extraction fraction by blood sampling to anticipate cerebral hyperperfusion phenomenon after carotid artery stenting
    Neurosurgery, 2014
    Co-Authors: Tomonori Iwata, Takahisa Mori, Yuhei Tanno, Shigen Kasakura, Yuichi Miyazaki, Yoshinori Aoyagi
    Abstract:

    BACKGROUND: Cerebral hyperperfusion syndrome sometimes occurs after carotid revascularization in patients with severe hemodynamic failure. To prevent cerebral hyperperfusion syndrome, cerebral hyperperfusion phenomenon (CHP) must be detected early. Single-photon emission computed tomography (SPECT) is useful for detecting CHP, but it is impractical on a daily basis. A tool with high availability to find CHP is desired. OBJECTIVE: To investigate whether global Oxygen extraction fraction (OEF) by a blood sampling method is useful for indicating CHP after carotid artery stenting (CAS). METHODS: When patients underwent elective CAS from September 2010 to August 2012, we performed blood sampling for OEF calculation and SPECT before and immediately after elective CAS. Data were collected prospectively. OEF was calculated from the cerebral Arteriovenous Oxygen Difference. Cerebral blood flow was measured in the affected middle cerebral artery (MCA) territory and in the ipsilateral cerebellum by SPECT. The ratio of MCA to cerebellar activity was defined as cerebral blood flow in the affected MCA territory divided by cerebral blood flow in the ipsilateral cerebellar hemisphere. Probable CHP was defined as ≥10% increase in the ratio of MCA to cerebellar activity after CAS. The relationship between peri-CAS OEF and probable CHP was evaluated. RESULTS: Of the 96 patients enrolled, 92 patients were analyzed. Probable CHP occurred in 17 patients. Post-CAS OEF was related to probable CHP (P < .01), but pre-CAS OEF was not. The receiver-operating characteristic curve showed that the cutoff value was 45% for probable CHP (P < .001). CONCLUSION: An increase in blood sampling OEF immediately after CAS was related to probable CHP; then the Oxygen demand should be reduced.