The Influence of Number of Signal Average Variation to the Scan Time and Anatomic Information of Lumbar MRI on Sagittal Slice with Stir Sequence

Background : Parallel imaging is one of the MRI Scanning techniques used to reduce the overall scan time when the patients with unvoluntary movement being examined with a low magnetic field of 0,35 T. This research aims to determine the difference between the clinical image quality of the conventional turbo spin echo (TSE) with mSENSE and that of the TSE with GRAPPA parallel imaging techniques from which resulting the MRI T1 and T2 Weighted Images (T1WI and T2WI) sagittal view of lumbar spines, and to define the techniques that clinically provide the most approriate anatomical information.Methods : This experimental study is made performed by the MRI 0.35 T in which 10 patients who had hernia nucleus pulposus (HNP) desease participated in the experiments ramdomly. The appointed Radiologists blended in the image evaluation using an image checklist to assess the visualisation of anatomical organs on the resulted sagittal lumbar MRI T1WI and T2WI. The two non-parametric statistical tools, Friedman test and the post hoc Wilcoxon matched pairs test, is used to analyze all the data descriptively. Testing the resesearch hypotheses with 95% of confident interval is to proved the differences between resulted sagittal lumbar MRI T1WI and T2WI..Results : The results shown there is a significant difference on the image quality of anatomical information when conventional TSE, parallel imaging-mSENSE and -GRAPPA, with T1WI are applied in the imaging techniques. When those imaging techniques are employed to obtain T2WI, the result is not significant in contrast.Conclusion : Good imaging techniques with adequate clinical image quality are ranked sequently as the conventional TSE, the mSENSE and GRAPPA.

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Coronal STIR sequence, a simple adjustment to routine MRI protocol for extra-spinal sciatica and sciatica-like symptoms

Egyptian Journal of Radiology and Nuclear Medicine ◽

10.1186/s43055-019-0096-6 ◽

2019 ◽

Vol 50 (1) ◽

Author(s):

Rania Zeitoun ◽

Mohammed Saleh Ali Mohieddin

Keyword(s):

Young Adults ◽

Soft Tissue ◽

Mr Imaging ◽

Age Groups ◽

Field Of View ◽

Mri Protocol ◽

Stir Sequence ◽

Tissue Abnormalities ◽

Additional Value ◽

Bone Abnormalities

Abstract Background The value of adding coronal STIR images to MR imaging of sciatica aiming to detect extra-spinal abnormalities. Results Additional coronal STIR images detected extra-spinal abnormalities in 20% of the patients, thereby downgraded the normal studies from 21 to 13%. The extra-spinal abnormalities included bone abnormalities (36.4%), soft tissue abnormalities (4.5%), neurological abnormalities (2.3%), gynecological abnormalities (50%), and miscellaneous (6.8%). In 6.9% of patients, the extra-spinal abnormalities explained the patients’ pain and influenced their management. Extra-spinal causes of pain significantly correlated to positive trauma and neoplasm history, normal routine protocol images, and absent nerve root impingement. Extra-spinal abnormalities were more prevalent in age groups (20–39 years). Conclusion Coronal STIR images (field of view: mid abdomen to the lesser trochanters) identify extra-spinal abnormalities that maybe overlooked on routine MRI protocol. It is of additional value in young adults, trauma, neoplasm, and negative routine images.

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Radial self-navigated native magnetic resonance angiography in comparison to navigator-gated contrast-enhanced MRA of the entire thoracic aorta in an aortic patient collective

Journal of Cardiovascular Magnetic Resonance ◽

10.1186/s12968-021-00774-9 ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Martina Correa Londono ◽

Nino Trussardi ◽

Verena C. Obmann ◽

Davide Piccini ◽

Michael Ith ◽

...

Keyword(s):

Magnetic Resonance ◽

Image Quality ◽

Magnetic Resonance Angiography ◽

Thoracic Aorta ◽

Aortic Root ◽

Aortic Disease ◽

Ascending Aorta ◽

Scan Time ◽

Contrast Enhanced

Abstract Background The native balanced steady state with free precession (bSSFP) magnetic resonance angiography (MRA) technique has been shown to provide high diagnostic image quality for thoracic aortic disease. This study compares a 3D radial respiratory self-navigated native MRA (native-SN-MRA) based on a bSSFP sequence with conventional Cartesian, 3D, contrast-enhanced MRA (CE-MRA) with navigator-gated respiration control for image quality of the entire thoracic aorta. Methods Thirty-one aortic native-SN-MRA were compared retrospectively (63.9 ± 10.3 years) to 61 CE-MRA (63.1 ± 11.7 years) serving as a reference standard. Image quality was evaluated at the aortic root/ascending aorta, aortic arch and descending aorta. Scan time was recorded. In 10 patients with both MRA sequences, aortic pathologies were evaluated and normal and pathologic aortic diameters were measured. The influence of artifacts on image quality was analyzed. Results Compared to the overall image quality of CE-MRA, the overall image quality of native-SN-MRA was superior for all segments analyzed (aortic root/ascending, p < 0.001; arch, p < 0.001, and descending, p = 0.005). Regarding artifacts, the image quality of native-SN-MRA remained superior at the aortic root/ascending aorta and aortic arch before and after correction for confounders of surgical material (i.e., susceptibility-related artifacts) (p = 0.008 both) suggesting a benefit in terms of motion artifacts. Native-SN-MRA showed a trend towards superior intraindividual image quality, but without statistical significance. Intraindividually, the sensitivity and specificity for the detection of aortic disease were 100% for native-SN-MRA. Aortic diameters did not show a significant difference (p = 0.899). The scan time of the native-SN-MRA was significantly reduced, with a mean of 05:56 ± 01:32 min vs. 08:51 ± 02:57 min in the CE-MRA (p < 0.001). Conclusions Superior image quality of the entire thoracic aorta, also regarding artifacts, can be achieved with native-SN-MRA, especially in motion prone segments, in addition to a shorter acquisition time.

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A Real-Time, Automatic, and Dynamic Scheduling and Control System for PET Patients Based on Wearable Sensors

Sensors ◽

10.3390/s21041104 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1104

Author(s):

Shin-Yan Chiou ◽

Kun-Ju Lin ◽

Ya-Xin Dong

Keyword(s):

Control System ◽

Real Time ◽

Human Error ◽

Dynamic Scheduling ◽

Wearable Sensors ◽

Time Data ◽

Scan Time ◽

Number Of Patients ◽

And Control ◽

Automatic Scheduling

Positron emission tomography (PET) is one of the commonly used scanning techniques. Medical staff manually calculate the estimated scan time for each PET device. However, the number of PET scanning devices is small, the number of patients is large, and there are many changes including rescanning requirements, which makes it very error-prone, puts pressure on staff, and causes trouble for patients and their families. Although previous studies proposed algorithms for specific inspections, there is currently no research on improving the PET process. This paper proposes a real-time automatic scheduling and control system for PET patients with wearable sensors. The system can automatically schedule, estimate and instantly update the time of various tasks, and automatically allocate beds and announce schedule information in real time. We implemented this system, collected time data of 200 actual patients, and put these data into the implementation program for simulation and comparison. The average time difference between manual and automatic scheduling was 7.32 min, and it could reduce the average examination time of 82% of patients by 6.14 ± 4.61 min. This convinces us the system is correct and can improve time efficiency, while avoiding human error and staff pressure, and avoiding trouble for patients and their families.

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Contrast-agent free evaluation of cardiomyopathies with T1 mapping and the new fast strain-encoded (fSENC) magnetic resonance imaging

European Heart Journal ◽

10.1093/ehjci/ehaa946.0218 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

K Hirschberg ◽

O Paul ◽

J Salatzki ◽

F Andre ◽

J Riffel ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Contrast Agent ◽

T1 Mapping ◽

Hypertensive Heart Disease ◽

Study Groups ◽

Resonance Imaging ◽

Gadolinium Enhancement ◽

Scan Time ◽

Normal Individuals

Abstract Background Cardiomyopathies (CMP) may cause impairment of cardiac function and structure. Cardiac Magnetic Resonance Imaging (CMR) is used for analysis and risk stratification of CMP by Late Gadolinium Enhancement (LGE). However, T1 mapping (T1) and fast strain encoded (f-SENC) sequences allow contrast-free and faster exams. The aim of this study was to characterize CMP by T1 and f-SENC to develop a faster and safer CMR protocol (fast-CMR). Methods CMP scans from our CMR database were retrospectively analyzed. All patients were scanned at 1.5T/3T scanner. Study groups were divided as follows: Patients with normal findings, dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), hypertensive heart disease (HHD) and cardiac amyloidosis. Global T1 times, longitudinal (GLS) and circumferential (GCS) strain using f-SENC of study groups were compared to healthy individuals (controls). Scan time and amount of gadolinium-based contrast agent (CA) in CMR-protocol with LGE were compared to fast-CMR. Results 174 patients and 31 controls were recruited. T1 times, GLS and GCS were similar between controls and normal individuals. T1 times were significantly increased (p<0.05), while GLS and GCS were significantly reduced (p<0.05) in all CMR study groups compared to controls (Table 1). Using fast-CMR 21 (±6) min of scan time were saved, about 47%, and 9 (±2) ml of CA were saved per patient. Conclusion Normal findings could be identified by fast-CMR without contrast agent. Fast CMR might also be a useful tool to identify different forms of CMP. Funding Acknowledgement Type of funding source: None

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Predictors of outcome in a large retrospective cohort of patients with transverse myelitis

Multiple Sclerosis Journal ◽

10.1177/1352458517731911 ◽

2017 ◽

Vol 24 (13) ◽

pp. 1743-1752 ◽

Cited By ~ 2

Author(s):

Matteo Gastaldi ◽

Enrico Marchioni ◽

Paola Banfi ◽

Valeria Mariani ◽

Laura Di Lodovico ◽

...

Keyword(s):

Nervous System ◽

Connective Tissue ◽

Autoimmune Diseases ◽

Inflammatory Diseases ◽

Univariate Analysis ◽

Transverse Myelitis ◽

Inflammatory Disorder ◽

Prognostic Assessment ◽

Lumbar Mri ◽

Post Infectious

Background: Transverse myelitis (TM) is an inflammatory disorder that can be idiopathic or associated with central nervous system autoimmune/dysimmune inflammatory diseases, connective tissue autoimmune diseases, or post-infectious neurological syndromes. Prognosis of initial TM presentations is uncertain. Objective: To identify outcome predictors in TM. Methods: Retrospective study on isolated TM at onset. Scores ⩾3 on the modified Rankin scale (mRS) marked high disability. Results: A total of 159 patients were identified. TM was classified as follows: idiopathic (I-TM, n = 53), post-infectious (PI-TM, n = 48), associated with multiple sclerosis (MS-TM, n = 51), or neuromyelitis optica spectrum disorders/connective tissue autoimmune diseases/neurosarcoidosis ( n = 7). At follow-up (median, 55 months; interquartile range, 32–80), 42 patients were severely disabled, and patients with I-TM or PI-TM showed the worst outcomes. Predictors of disability were infectious antecedents, sphincter and pyramidal symptoms, high mRS scores, blood–cerebrospinal fluid barrier damage, lumbar magnetic resonance imaging (MRI) lesions on univariate analysis, and older age (odds ratio (OR), 1.1; 95% confidence interval (CI), 1.0–1.1), overt/subclinical involvement of the peripheral nervous system (PNS) (OR, 9.4; 95% CI, 2.2–41.0), complete TM (OR, 10.8; 95% CI, 3.4–34.5) on multivariate analysis. Conclusion: Our findings help define prognosis and therapies in TM at onset. Infectious antecedents and PNS involvement associate with severe prognosis. Nerve conduction studies and lumbar MRI could improve the prognostic assessment of this condition.

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Delayed image of iodine-123 iomazenil as a relative map of benzodiazepine receptor binding: The optimal scan time

European Journal of Nuclear Medicine ◽

10.1007/bf01254474 ◽

1996 ◽

Vol 23 (11) ◽

pp. 1491-1497 ◽

Cited By ~ 18

Author(s):

Yoshihiro Onishi ◽

Yoshiharu Yonekura ◽

Fumiko Tanaka ◽

Sadahiko Nishizawa ◽

Hidehiko Okazawa ◽

...

Keyword(s):

Receptor Binding ◽

Benzodiazepine Receptor ◽

Scan Time ◽

Delayed Image ◽

Iodine 123

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The remnant of primary head sinus found in the case of dural arteriovenous fistula: A case report

Interventional Neuroradiology ◽

10.1177/1591019916641903 ◽

2016 ◽

Vol 22 (4) ◽

pp. 452-456 ◽

Cited By ~ 1

Author(s):

Katsuhiro Mizutani ◽

Takenori Akiyama ◽

Kazunari Yoshida

Keyword(s):

Arteriovenous Fistula ◽

Dural Arteriovenous Fistula ◽

Rare Condition ◽

Venous Drainage ◽

Petrous Bone ◽

Jugular Bulb ◽

Cone Beam ◽

Middle Fossa ◽

Rotational Angiography ◽

Anatomic Information

In the embryo, the primary head sinus (PHS) is the first venous drainage channel in the craniocervical region. During embryonic development, this channel regresses and usually disappears completely; accordingly, a remnant of the PHS is an extremely rare condition and has been described in only a few previous studies. Here, we report a case of remnant of the PHS with a dural arteriovenous fistula (dAVF) in an adult. The remnant of the PHS had penetrated the petrous bone to run from the middle fossa to the jugular bulb and served as a drain for the middle fossa dAVF. We used digital subtraction angiography and reconstructed cone-beam computed tomography in 3D rotational angiography to obtain detailed anatomic information about the remnant PHS and additionally scrutinised and discussed its features.

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Evaluation of baroreceptor reflex by blood pressure monitoring in unanesthetized cats

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1988.254.2.h377 ◽

1988 ◽

Vol 254 (2) ◽

pp. H377-H383 ◽

Cited By ~ 104

Author(s):

G. Bertinieri ◽

M. Di Rienzo ◽

A. Cavallazzi ◽

A. U. Ferrari ◽

A. Pedotti ◽

...

Keyword(s):

Blood Pressure ◽

Regression Coefficient ◽

Blood Pressure Monitoring ◽

Sinus Node ◽

Pulse Interval ◽

Pressure Monitoring ◽

Physiological Conditions ◽

Average Variation

The arterial baroreceptor control of the sinus node operating in unanesthetized conditions was evaluated in 10 cats in which blood pressure was recorded intra-arterially and scanned by a computer to identify the "spontaneous" sequences of three or more consecutive beats in which systolic blood pressure (SBP) progressively rose and pulse interval (PI) progressively lengthened (type 1 sequences) or SBP progressively fell and PI progressively shortened (type 2 sequences). Many type 1 and 2 three-beat sequences were found; four-, five-, and six-beat sequences of either type were progressively less common, and sequences longer than six beats were almost never identified. The regression coefficient was 30% greater for type 1 than for type 2 sequences. However a prominent feature of either regression coefficient was a wide scattering in each cat (average variation coefficient 50.9 +/- 5.5%). The regression coefficient values were related to some extent to the PI but not to the SBP existing at the beginning of the sequence. Sinoaortic denervation dramatically reduced the number of sequences of either type. These data validate a method for collecting a large number of observations on the baroreceptor-heart rate reflex in physiological conditions. This method may improve understanding of baroreflex involvement in integrated cardiovascular regulation.

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Event-Locked Time-Resolved Fourier Spectroscopy

Applied Spectroscopy ◽

10.1366/0003702971941917 ◽

1997 ◽

Vol 51 (8) ◽

pp. 1106-1112 ◽

Cited By ~ 20

Author(s):

H. Weidner ◽

R. E. Peale

Keyword(s):

Signal To Noise Ratio ◽

Low Cost ◽

Michelson Interferometer ◽

Far Infrared ◽

Time Base ◽

The Novel ◽

Time Resolved ◽

Mathematical Algorithm ◽

Scan Time ◽

Recorded Data

A low-cost method of adding time-resolving capability to commercial Fourier transform spectrometers with a continuously scanning Michelson interferometer has been developed. This method is specifically designed to eliminate noise and artifacts caused by mirror-speed variations in the interferometer. The method exists of two parts: (1) a novel timing scheme for synchronizing the transient events under study and the digitizing of the interferogram and (2) a mathematical algorithm for extracting the spectral information from the recorded data. The novel timing scheme is a modification of the well-known interleaved, or stroboscopic, method. It achieves the same timing accuracy, signal-to-noise ratio, and freedom from artifacts as step-scan time-resolving Fourier spectrometers by locking the sampling of the interferogram to a stable time base rather than to the occurrences of the HeNe fringes. The necessary pathlength-difference information at which samples are taken is obtained from a record of the mirror speed. The resulting interferograms with uneven pathlength-difference spacings are transformed into wavenumber space by least-squares fits of periodic functions. Spectra from the far-infrared to the upper visible at resolutions up to 0.2 cm−1 are used to demonstrate the utility of this method.

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