ABSTRACT The aim of this present study is to increase bandwidth (BW) and echo train length (ETL) ... more ABSTRACT The aim of this present study is to increase bandwidth (BW) and echo train length (ETL) in Proton Density Turbo Spin Echo (PD TSE) sequences with and without fat saturation (FS) as well as in Turbo Inversion Recovery Magnitude sequences (TIRM) in order to assess whether these sequences are capable of reducing susceptibility artifacts. We compared 1) TIRM coronal (COR) with the same sequence with increased both BW and ETL 2) Conventional PD TSE sagittal (SAG) with FS with an increased BW 3) Conventional PD TSE SAG without FS with an increased BW 4) Conventional PD TSE SAG without FS with increased both BW and ETL. A quantitative analysis was performed to measure the extent of the susceptibility artifacts. Furthermore, a qualitative analysis was performed by two radiologists in order to evaluate the susceptibility artifacts, image distortion and fat suppression. The depiction of cartilage, menisci, muscles, tendons and bone marrow were also qualitatively analyzed. The quantitative analysis found that the modified TIRM sequence is significantly superior to the conventional one regarding the extent of the susceptibility artifacts. In the qualitative analysis, the modified TIRM sequence was superior to the corresponding conventional one in eight characteristics out of ten that were analyzed. The modified PD TSE with FS was superior to the corresponding conventional one regarding the susceptibility artifacts, image distortion and depiction of bone marrow and cartilage while achieving effective fat saturation. The modified PD TSE sequence without FS with a high (H) BW was found to be superior corresponding to the conventional one in the case of cartilage. Consequently, TIRM sequence with an increased BW and ETL is proposed for producing images of high quality and modified PD TSE with H BW for smaller metals, especially when FS is used.
To assess the efficacy of the BLADE technique (MR imaging with &a... more To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space covering') to significantly reduce motion, truncation, flow and other artifacts in cervical spine compared to the conventional technique. In eighty consecutive subjects, who had been routinely scanned for cervical spine examination, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitative analysis was performed using the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0: non-visualization; 1: poor; 2: average; 3: good; 4: excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). In quantitative analysis, the CNR values of the CSF/SC between TIRM SAG and TIRM SAG BLADE were found to present statistically significant differences (p < 0.001). Regarding motion and truncation artifacts, the T2 TSE BLADE SAG was superior compared to the T2 TSE SAG, and the T2 TIRM BLADE SAG was superior compared to the T2 TIRM SAG. Regarding flow artifacts, T2 TIRM BLADE SAG eliminated more artifacts than T2 TIRM SAG. In cervical spine MRI, BLADE sequences appear to significantly reduce motion, truncation and flow artifacts and improve image quality. BLADE sequences are proposed to be used for uncooperative subjects. Nevertheless, more research needs to be done by testing additional specific pathologies.
ABSTRACT Purpose: The purpose of this study is to evaluate the ability of Proton Density (PD)‐BLA... more ABSTRACT Purpose: The purpose of this study is to evaluate the ability of Proton Density (PD)‐BLADE sequences in reducing or even eliminating motion and pulsatile flow artifacts in knee MRI examinations. Methods: Eighty consecutive patients, who had been routinely scanned for knee examination, participated in the study. The following pairs of sequences with and without BLADE were compared: a) PD Turbo Spin Echo (TSE) Sagittal (SAG) Fat Saturation (FS) in thirty five patients, b) PD TSE Coronal (COR) FS in nineteen patients, c) T2 TSE AXIAL in thirteen patients and d) PD TSE SAG in thirteen patients. Both qualitative and quantitative analyses were performed based on the signal‐to‐noise ratio (SNR), contrast‐to‐noise ratio (CNR), and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion and pulsation artifacts was evaluated. Results: Based on the results of the SNR, CRN and ReCon for the different sequences and anatomical structures, the BLADE sequences were significantly superior in nineteen cases, whereas the corresponding conventional sequences were significantly superior in six only cases. The BLADE sequences eliminated motion artifacts in all the cases. However, motion artifacts were shown in: a) six PD TSE SAG FS, b) three PD TSE COR FS, c) three PD TSE SAG, and d) two T2 TSE AXIAL conventional sequences. In our results, it was found that in PD FS sequences (Sagittal and Coronal) the differences between the BLADE and conventional sequences regarding the elimination of motion and pulsatile flow artifacts were statistically significant. In all the comparisons, the PD FS BLADE sequences (coronal and sagittal) were significantly superior to the corresponding conventional sequences regarding the classification of their image quality. Conclusion: This technique appears to be capable to potentially eliminate motion and pulsatile flow artifacts in knee MR images.
The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) e... more The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) examinations of uncooperative and cooperative patients. For each group of patients, the pairs of sequences that were compared were two T2-weighted (T2-W) fluid attenuated inversion recovery sequences with different k-space trajectories (conventional Cartesian and BLADE) and two T2-TSE weighted with different k-space trajectories (conventional Cartesian and BLADE). Twenty-three consecutive uncooperative patients and 44 cooperative patients, who routinely underwent brain MR imaging examination, participated in the study. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio, contrast-to-noise ratio (CNR), and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of motion, other (e.g., Gibbs, susceptibility artifacts, phase encoding from vessels) artifacts and pulsatile flow artifacts was evaluated. In the uncooperative group of patients, BLADE sequences were superior to the corresponding conventional sequences in all the cases. Furthermore, the differences were found to be statistically significant in almost all the cases. In the cooperative group of patients, BLADE sequences were superior to the conventional sequences with the differences of the CNR and ReCon values in nine cases being statistically significant. Furthermore, BLADE sequences eliminated motion and other artifacts and T2 FLAIR BLADE sequences eliminated pulsatile flow artifacts. BLADE sequences (T2-TSE and T2 FLAIR) should be used in brain MR examinations of uncooperative patients. In cooperative patients, T2-TSE BLADE sequences may be used as part of the routine protocol and orbital examinations. T2 FLAIR BLADE sequences may be used optionally in examinations of AVM, orbits, haemorrhages, ventricular lesions, lesions in the frontal lobe, periventricular lesions, lesions in regions close to artifacts and lesions in posterior fossa.
The purpose of this study is to evaluate the ability of proton density (PD)-BLADE sequences in re... more The purpose of this study is to evaluate the ability of proton density (PD)-BLADE sequences in reducing or even eliminating motion and pulsatile flow artifacts in knee magnetic resonance imaging examinations. Eighty consecutive patients, who had been routinely scanned for knee examination, participated in the study. The following pairs of sequences with and without BLADE were compared: (a) PD turbo spin echo (TSE) sagittal (SAG) fat saturation (FS) in 35 patients, (b) PD TSE coronal (COR) FS in 19 patients, (c) T2 TSE axial in 13 patients and (d) PD TSE SAG in 13 patients. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion and pulsation artifacts was evaluated. Based on the results of the SNR, CRN and ReCon for the different sequences ...
The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) e... more The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) examinations of uncooperative and cooperative patients. For each group of patients, the pairs of sequences that were compared were two T2-weighted (T2-W) fluid attenuated inversion recovery sequences with different k-space trajectories (conventional Cartesian and BLADE) and two T2-TSE weighted with different k-space trajectories (conventional Cartesian and BLADE). Twenty-three consecutive uncooperative patients and 44 cooperative patients, who routinely underwent brain MR imaging examination, participated in the study. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio, contrast-to-noise ratio (CNR), and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of motion, other (e.g., Gibbs, susceptibility artifacts, phase encoding from vessels) artifact...
To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space c... more To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space covering') to significantly reduce motion, truncation, flow and other artifacts in cervical spine compared to the conventional technique. In eighty consecutive subjects, who had been routinely scanned for cervical spine examination, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitative analysis was performed using the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0:non-visualization; 1:poor; 2:average; 3:good; 4:excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). In quantitative analysis, the CNR values of the CSF/SC between TIRM SAG and TIRM SAG BLADE were found to present statistically signif...
ABSTRACT The aim of this present study is to increase bandwidth (BW) and echo train length (ETL) ... more ABSTRACT The aim of this present study is to increase bandwidth (BW) and echo train length (ETL) in Proton Density Turbo Spin Echo (PD TSE) sequences with and without fat saturation (FS) as well as in Turbo Inversion Recovery Magnitude sequences (TIRM) in order to assess whether these sequences are capable of reducing susceptibility artifacts. We compared 1) TIRM coronal (COR) with the same sequence with increased both BW and ETL 2) Conventional PD TSE sagittal (SAG) with FS with an increased BW 3) Conventional PD TSE SAG without FS with an increased BW 4) Conventional PD TSE SAG without FS with increased both BW and ETL. A quantitative analysis was performed to measure the extent of the susceptibility artifacts. Furthermore, a qualitative analysis was performed by two radiologists in order to evaluate the susceptibility artifacts, image distortion and fat suppression. The depiction of cartilage, menisci, muscles, tendons and bone marrow were also qualitatively analyzed. The quantitative analysis found that the modified TIRM sequence is significantly superior to the conventional one regarding the extent of the susceptibility artifacts. In the qualitative analysis, the modified TIRM sequence was superior to the corresponding conventional one in eight characteristics out of ten that were analyzed. The modified PD TSE with FS was superior to the corresponding conventional one regarding the susceptibility artifacts, image distortion and depiction of bone marrow and cartilage while achieving effective fat saturation. The modified PD TSE sequence without FS with a high (H) BW was found to be superior corresponding to the conventional one in the case of cartilage. Consequently, TIRM sequence with an increased BW and ETL is proposed for producing images of high quality and modified PD TSE with H BW for smaller metals, especially when FS is used.
To assess the efficacy of the BLADE technique (MR imaging with &a... more To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space covering') to significantly reduce motion, truncation, flow and other artifacts in cervical spine compared to the conventional technique. In eighty consecutive subjects, who had been routinely scanned for cervical spine examination, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitative analysis was performed using the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0: non-visualization; 1: poor; 2: average; 3: good; 4: excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). In quantitative analysis, the CNR values of the CSF/SC between TIRM SAG and TIRM SAG BLADE were found to present statistically significant differences (p < 0.001). Regarding motion and truncation artifacts, the T2 TSE BLADE SAG was superior compared to the T2 TSE SAG, and the T2 TIRM BLADE SAG was superior compared to the T2 TIRM SAG. Regarding flow artifacts, T2 TIRM BLADE SAG eliminated more artifacts than T2 TIRM SAG. In cervical spine MRI, BLADE sequences appear to significantly reduce motion, truncation and flow artifacts and improve image quality. BLADE sequences are proposed to be used for uncooperative subjects. Nevertheless, more research needs to be done by testing additional specific pathologies.
ABSTRACT Purpose: The purpose of this study is to evaluate the ability of Proton Density (PD)‐BLA... more ABSTRACT Purpose: The purpose of this study is to evaluate the ability of Proton Density (PD)‐BLADE sequences in reducing or even eliminating motion and pulsatile flow artifacts in knee MRI examinations. Methods: Eighty consecutive patients, who had been routinely scanned for knee examination, participated in the study. The following pairs of sequences with and without BLADE were compared: a) PD Turbo Spin Echo (TSE) Sagittal (SAG) Fat Saturation (FS) in thirty five patients, b) PD TSE Coronal (COR) FS in nineteen patients, c) T2 TSE AXIAL in thirteen patients and d) PD TSE SAG in thirteen patients. Both qualitative and quantitative analyses were performed based on the signal‐to‐noise ratio (SNR), contrast‐to‐noise ratio (CNR), and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion and pulsation artifacts was evaluated. Results: Based on the results of the SNR, CRN and ReCon for the different sequences and anatomical structures, the BLADE sequences were significantly superior in nineteen cases, whereas the corresponding conventional sequences were significantly superior in six only cases. The BLADE sequences eliminated motion artifacts in all the cases. However, motion artifacts were shown in: a) six PD TSE SAG FS, b) three PD TSE COR FS, c) three PD TSE SAG, and d) two T2 TSE AXIAL conventional sequences. In our results, it was found that in PD FS sequences (Sagittal and Coronal) the differences between the BLADE and conventional sequences regarding the elimination of motion and pulsatile flow artifacts were statistically significant. In all the comparisons, the PD FS BLADE sequences (coronal and sagittal) were significantly superior to the corresponding conventional sequences regarding the classification of their image quality. Conclusion: This technique appears to be capable to potentially eliminate motion and pulsatile flow artifacts in knee MR images.
The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) e... more The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) examinations of uncooperative and cooperative patients. For each group of patients, the pairs of sequences that were compared were two T2-weighted (T2-W) fluid attenuated inversion recovery sequences with different k-space trajectories (conventional Cartesian and BLADE) and two T2-TSE weighted with different k-space trajectories (conventional Cartesian and BLADE). Twenty-three consecutive uncooperative patients and 44 cooperative patients, who routinely underwent brain MR imaging examination, participated in the study. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio, contrast-to-noise ratio (CNR), and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of motion, other (e.g., Gibbs, susceptibility artifacts, phase encoding from vessels) artifacts and pulsatile flow artifacts was evaluated. In the uncooperative group of patients, BLADE sequences were superior to the corresponding conventional sequences in all the cases. Furthermore, the differences were found to be statistically significant in almost all the cases. In the cooperative group of patients, BLADE sequences were superior to the conventional sequences with the differences of the CNR and ReCon values in nine cases being statistically significant. Furthermore, BLADE sequences eliminated motion and other artifacts and T2 FLAIR BLADE sequences eliminated pulsatile flow artifacts. BLADE sequences (T2-TSE and T2 FLAIR) should be used in brain MR examinations of uncooperative patients. In cooperative patients, T2-TSE BLADE sequences may be used as part of the routine protocol and orbital examinations. T2 FLAIR BLADE sequences may be used optionally in examinations of AVM, orbits, haemorrhages, ventricular lesions, lesions in the frontal lobe, periventricular lesions, lesions in regions close to artifacts and lesions in posterior fossa.
The purpose of this study is to evaluate the ability of proton density (PD)-BLADE sequences in re... more The purpose of this study is to evaluate the ability of proton density (PD)-BLADE sequences in reducing or even eliminating motion and pulsatile flow artifacts in knee magnetic resonance imaging examinations. Eighty consecutive patients, who had been routinely scanned for knee examination, participated in the study. The following pairs of sequences with and without BLADE were compared: (a) PD turbo spin echo (TSE) sagittal (SAG) fat saturation (FS) in 35 patients, (b) PD TSE coronal (COR) FS in 19 patients, (c) T2 TSE axial in 13 patients and (d) PD TSE SAG in 13 patients. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of image motion and pulsation artifacts was evaluated. Based on the results of the SNR, CRN and ReCon for the different sequences ...
The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) e... more The purpose of this study is to compare two types of sequences in brain magnetic resonance (MR) examinations of uncooperative and cooperative patients. For each group of patients, the pairs of sequences that were compared were two T2-weighted (T2-W) fluid attenuated inversion recovery sequences with different k-space trajectories (conventional Cartesian and BLADE) and two T2-TSE weighted with different k-space trajectories (conventional Cartesian and BLADE). Twenty-three consecutive uncooperative patients and 44 cooperative patients, who routinely underwent brain MR imaging examination, participated in the study. Both qualitative and quantitative analyses were performed based on the signal-to-noise ratio, contrast-to-noise ratio (CNR), and relative contrast (ReCon) measures of normal anatomic structures. The qualitative analysis was performed by experienced radiologists. Also, the presence of motion, other (e.g., Gibbs, susceptibility artifacts, phase encoding from vessels) artifact...
To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space c... more To assess the efficacy of the BLADE technique (MR imaging with 'rotating blade-like k-space covering') to significantly reduce motion, truncation, flow and other artifacts in cervical spine compared to the conventional technique. In eighty consecutive subjects, who had been routinely scanned for cervical spine examination, the following pairs of sequences were compared: a) T2 TSE SAG vs. T2 TSE SAG BLADE and b) T2 TIRM SAG vs. T2 TIRM SAG BLADE. A quantitative analysis was performed using the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measures. A qualitative analysis was also performed by two radiologists, who graded seven image characteristics on a 5-point scale (0:non-visualization; 1:poor; 2:average; 3:good; 4:excellent). The observers also evaluated the presence of image artifacts (motion, truncation, flow, indentation). In quantitative analysis, the CNR values of the CSF/SC between TIRM SAG and TIRM SAG BLADE were found to present statistically signif...
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