Reliability of High-resolution Gadolinium-enhanced MR Cisternography and Gasket-seal Technique for Management of Anterior Skull Base Defects.

PURPOSE: Precise preoperative localization of anterior skull base defects is important to plan surgical access, increase the success rate and reduce complications. A stable closure of the defect is vital to prevent recurrence of cerebrospinal fluid (CSF) rhinorrhea. The purpose of this retrospective case series was to evaluate the reliability of a new high-resolution gadolinium-enhanced compressed-sensing SPACE technique (CS T1 SPACE) for magnetic resonance (MR) cisternography to detect cerebrospinal fluid leaks of the anterior skull base and to assess the long-term success rate of the gasket-seal technique for closure of skull base defects. METHOD: All patients with spontaneous or postoperative cerebrospinal fluid rhinorrhea and defects of the anterior skull base presenting to the Departments of Otorhinolaryngology and Neurosurgery between 2019 and 2020, receiving a computed tomography (CT) cisternography and MR cisternography (on a 3T whole-body MR scanner using a 64-channel head and neck coil) with CS T1 SPACE sequence and closure of the defect with the gasket-seal technique, were enrolled in the study. For the cisternography, iodinated contrast agent (15 ml Solutrast 250 M®), saline (4 mL) mixed with a 0.5 mL of gadoteridol was injected into the lumbar subarachnoid space. RESULTS: A total of four patients were included in the study and MR cisternography with CS T1 SPACE sequence was able to precisely localize CSF leaks in all patients. The imaging results correlated with intraoperative findings. All defects could be successfully closed with the gasket-seal technique. The mean follow-up was 35.25 months (range 33-37 months). CONCLUSION: MR cisternography with CS T1 SPACE sequence could be a promising technique for precise localization of CSF leaks and the gasket-seal technique resulted in good closure of the CSF fistula in this case series.

Rapid Whole Genome Sequencing Diagnoses and Guides Treatment in Critically Ill Children in Belgium in Less than 40 Hours.

Rapid Whole Genome Sequencing (rWGS) represents a valuable exploration in critically ill pediatric patients. Early diagnosis allows care to be adjusted. We evaluated the feasibility, turnaround time (TAT), yield, and utility of rWGS in Belgium. Twenty-one unrelated critically ill patients were recruited from the neonatal intensive care units, the pediatric intensive care unit, and the neuropediatric unit, and offered rWGS as a first tier test. Libraries were prepared in the laboratory of human genetics of the University of Liège using Illumina DNA PCR-free protocol. Sequencing was performed on a NovaSeq 6000 in trio for 19 and in duo for two probands. The TAT was calculated from the sample reception to the validation of results. Clinical utility data were provided by treating physicians. A definite diagnosis was reached in twelve (57.5%) patients in 39.80 h on average (range: 37.05-43.7). An unsuspected diagnosis was identified in seven patients. rWGS guided care adjustments in diagnosed patients, including a gene therapy, an off-label drug trial and two condition-specific treatments. We successfully implemented the fastest rWGS platform in Europe and obtained one of the highest rWGS yields. This study establishes the path for a nationwide semi-centered rWGS network in Belgium.

Depiction of detailed surgical anatomy and CSF flow information using a single MRI technique.

We describe a novel MRI sequence (T2 SPACE) capable of demonstrating detailed structural anatomy and functional CSF flow information simultaneously. While traditionally, a variety of sequences are utilised for this purpose, we have highlighted the advantages of this technique over traditional approaches, using example of a patient with CSF loculation in prepontine/suprasellar cistern, causing third ventricular compression and hydrocephalus. The sequence depicted the surgical anatomy by showing the web/cyst wall as well as CSF flow entering the cyst potentially causing increased pressure.

Contrast-enhanced 3D-T2-weighted SPACE sequence for MRI detection and localization of adrenocorticotropin (ACTH)-secreting pituitary microadenomas.

OBJECTIVE: Cushing disease is a potentially fatal endocrine disorder caused by adrenocorticotropin (ACTH)-secreting microadenomas in the pituitary gland. Accurate detection and localization of the adenomas is the key to clinical treatment. This study analysed the value of contrast-enhanced Sampling Perfection with Application-optimized Contrasts using different flip angle Evolutions (SPACE) sequence in magnetic resonance imaging (MRI) assessment of ACTH-secreting pituitary microadenomas. DESIGN AND PATIENTS: We carried out a retrospective study in which 45 patients with ACTH-secreting pituitary microadenomas were enrolled. Dynamic contrast-enhanced (DCE) coronal T1-SE sequence was performed. A contrast-enhanced coronal SPACE sequence was added immediately after DCE MRI finished. Two independent observers assessed the tumour existence and location, then the results were compared with surgical findings. RESULTS: Twenty-four lesions (53.3%) were detected by the DCE T1-SE sequence alone, while 35 lesions (80.0%) were detected with the addition of contrast-enhanced SPACE sequence. The sensitivity (58.5% vs. 85.3%; p < .05) and best diagnostic accuracy (62.0% vs. 84.4%; p < .05) were significantly better for addition with SPACE sequence than DCE-SE images alone in detection of ACTH-secreting pituitary microadenomas. For lesions <5 mm, the detected numbers were 4 (16.6%) versus 10 (27.8%) by DCE T1-SE sequence and combined DCE T1-SE with SPACE sequence. CONCLUSIONS: A combination of contrast-enhanced SPACE with DCE T1-SE sequence could improve the detection of ACTH-secreting pituitary microadenomas. Contrast-enhanced SPACE sequence could be a supplementary sequence for imaging of ACTH-secreting pituitary adenomas when T1-SE sequence provides negative or equivocal findings.

Evaluation of craniocervical pseudomeningoceles with three-dimensional T2-SPACE sequence at 3T.

BACKGROUND: Pseudomingocele is a postoperative fluid collection adjacent to the dural membrane. The distinction of pseudomeningocele from other postoperative collections is very important. PURPOSE: To show the efficacy of three-dimensional (3D) T2-weighted sampling perfection with application-optimized contrasts using a different flip-angle evolution (SPACE) magnetic resonance imaging (MRI) sequence in the diagnosis of pseudomeningocele in which conventional MRI sequences may be insufficient. MATERIAL AND METHODS: A total of 10 patients were included in the study. All of these patients also had 3D T2-SPACE high-resolution volumetric MR image in addition to conventional cervical and cerebral MR sequences. All MR examinations were reviewed by two neuroradiologists. RESULTS: Pseudomeningocele neck was shown in six patients by both conventional sequences and SPACE sequence. In two patients, the neck was only shown in the SPACE sequence. Four pseudomeningocele necks were shown to have flow void with both conventional sequences and SPACE sequence. Flow void could only be demonstrated by SPACE sequence in two patients. CONCLUSION: A T2-SPACE sequence can show the presence of pseudomeningocele neck and flow void even in cases where conventional MRI cannot show, thus contributing to the diagnosis of pseudomeningocele. Therefore, especially in postoperative imaging, the T2-SPACE sequence may be included in routine sequences to make the differential diagnosis correctly.

Quality comparison between three-dimensional T2-weighted SPACE and two-dimensional T2-weighted turbo spin echo magnetic resonance images for the brachytherapy planning evaluation of prostate and periprostatic anatomy.

PURPOSE: The purpose of this study was to compare an isotropic three-dimensional (3D) T2-weighted sequence sampling perfection with application-optimized contrasts by using flip angle evolution (SPACE) with an axial two-dimensional T2-weighted turbo spin echo (TSE) sequence with regard to overall image quality and the delineation of normal prostate and periprostatic anatomy for low-dose-rate prostate cancer brachytherapy planning evaluation. METHODS AND MATERIALS: Patients (n = 69) with prostate cancer who had pelvic magnetic resonance imaging (MRI) for low-dose-rate brachytherapy treatment planning were included. Three radiologists independently assessed the visibility of nine anatomic structures on each sequence by using a 5-point scale and overall image quality by using a 4-point scale. The significance of the differences in diagnostic performance was tested with a Wilcoxon signed rank test. RESULTS: No significant intersequence differences were found for most (7/9) anatomical structures and overall image quality. The mean scores for visibility of anatomical structures on the 3D SPACE and 2D TSE sequences, respectively, were as follows: the zonal anatomy (3.7; 3.9, p = 0.05), prostate capsule (3.9; 4.0, p = 0.08), neurovascular bundle (2.9; 2.9, p = 0.9), rectoprostatic angle (3.8; 3.8, p = 0.35), rectum (4.2; 4.3, p = 0.26), urethra (3.8; 3.9, p = 0.12), urinary bladder (4.6; 4.6, p = 0.61), and overall image quality (2.9; 2.9, p = 0.33). 3D SPACE was superior for delineation of the genitourinary diaphragm (3.8; 3.6, p = 0.003), whereas 2D TSE was superior for delineation of the seminal vesicles (3.5; 4.0, p < 0.0001). CONCLUSIONS: Anatomic delineation of the prostatic and periprostatic anatomy provided by the 3D SPACE sequence is as robust in quality as that provided by a conventional 2D TSE sequence with superior delineation of the genitourinary diaphragm. For MRI-based brachytherapy treatment planning, the 3D SPACE sequence with subcentimeter isotropic resolution can replace the 2D TSE sequence and be incorporated into standard MRI protocols.

Feasibility of High-Resolution 3-Dimensional Sampling Perfection with Application-Optimized Contrast Using Different Flip Angle Evolution Imaging for the Preoperative Detection of Parasinus Meningioma: A Pilot Study Compared with Contrast-Enhanced Magnetic Resonance Venography.

OBJECTIVES: To prospectively evaluate the diagnostic value of 3.0 Tesla magnetic resonance 3-dimensional sampling perfection with application-optimized contrast using different flip angle evolution (3D-SPACE) in the detection of sinus wall invasion and sinus patency in parasinus meningiomas. METHODS: In this study, 28 patients with suspected meningiomas adjacent to the venous sinus underwent conventional magnetic resonance imaging, contrast-enhanced magnetic resonance venography, and 3D-SPACE scans. We collected patient charts and surgical reports for demographic details, histologic analysis, and neurologic performance preoperatively and postoperatively. Images obtained by each technique were assessed independently by 2 neurosurgeons for characteristics of sinus infiltration, wall invasion, lumen patency, and collateral veins. RESULTS: The blood flow signal inside the lumen and collateral veins were depressed and presented as black, contrasting well with the sinus wall on 3D-SPACE imaging. When the curved-planar reconstruction images were combined, it was intuitive and accurate to detect the extent of sinus wall invasion by meningioma and also to detect lumen patency. An intratumoral "false lumen" was shown to maintain the blood flow inside the sinus at a totally invaded lesion. Moreover, collateral veins enveloped in a meningioma with their confluence points of the venous sinus were easily observed on 3D-SPACE images. CONCLUSION: With an integrative presentation of parasinus meningioma, wall invasion, lumen patency, and collateral veins, high-resolution 3D-SPACE imaging provides a reliable technique to accurately assess venous sinus invasion preoperatively.

Preoperative detection of malignant liver tumors: Comparison of 3D-T2-weighted sequences with T2-weighted turbo spin-echo and single shot T2 at 1.5 T.

PURPOSE: To assess the performances of three-dimensional (3D)-T2-weighted sequences compared to standard T2-weighted turbo spin echo (T2-TSE), T2-half-Fourier acquisition single-shot turbo spin-echo (T2-HASTE), diffusion weighted imaging (DWI) and 3D-T1-weighted VIBE sequences in the preoperative detection of malignant liver tumors. METHODS: From 2012 to 2015, all patients of our institution undergoing magnetic resonance imaging (MRI) examination for suspected malignant liver tumors were prospectively included. Patients had contrast-enhanced 3D-T1-weighted, DWI, 3D-T2-SPACE, T2-HASTE and T2-TSE sequences. Imaging findings were compared with those obtained at follow-up, surgery and histopathological analysis. Sensitivities for the detection of malignant liver tumors were compared for each sequence using McNemar test. A subgroup analysis was conducted for HCCs. Image artifacts were analyzed and compared using Wilcoxon paired signed rank-test. RESULTS: Thirty-three patients were included: 13 patients had 40 hepatocellular carcinomas (HCC) and 20 had 54 liver metastases. 3D-T2-weighted sequences had a higher sensitivity than T2-weighted TSE sequences for the detection of malignant liver tumors (79.8% versus 68.1%; P < 0.001). The difference did not reach significance for HCC. T1-weighted VIBE and DWI had a higher sensitivity than T2-weighted sequences. 3D-T2-weighted-SPACE sequences showed significantly less artifacts than T2-weitghted TSE. CONCLUSION: 3D-T2-weighted sequences show very promising performances for the detection of liver malignant tumors compared to T2-weighted TSE sequences.

Role of 3D SPACE sequence and susceptibility weighted imaging in the evaluation of hydrocephalus and treatment-oriented refined classification of hydrocephalus.

OBJECTIVE: The aim of our study was to evaluate the diagnostic utility of three-dimensional sampling perfection with application optimized contrast using different flip angle evolution (3D SPACE) sequence and Susceptibility Weighted Imaging (SWI) in hydrocephalus and to propose a refined definition and classification of hydrocephalus with relevance to the selection of treatment option. MATERIALS AND METHODS: A prospective study of 109 patients with hydrocephalus was performed with magnetic resonance imaging (MRI) brain using standardized institutional sequences along with additional sequences 3D SPACE and SWI. The images were independently read by two senior neuroradiologists and the etiopathogenesis of hydrocephalus was arrived by consensus. RESULTS: With conventional sequences, 46 out of 109 patients of hydrocephalus were diagnosed as obstructive of which 21 patients showed direct signs of obstruction and 25 showed indirect signs. In the remaining 63 patients of communicating hydrocephalus, cause could not be found out in 41 patients. Whereas with 3D SPACE sequence, 88 patients were diagnosed as obstructive hydrocephalus in which all of them showed direct signs of obstruction and 21 patients were diagnosed as communicating hydrocephalus. By including SWI, we found out hemorrhage causing intraventricular obstruction in three patients and hemorrhage at various sites in 24 other patients. With these findings, we have classified the hydrocephalus into communicating and noncommunicating, with latter divided into intraventricular and extraventricular obstruction, which is very well pertaining to the selection of surgical option. CONCLUSION: We strongly suggest to include 3D SPACE and SWI sequences in the set of routine MRI sequences, as they are powerful diagnostic tools and offer complementary information regarding the precise evaluation of the etiopathogenesis of hydrocephalus and have an effective impact in selecting the mode of management.

Value of three-dimensional SPACE sequence on analysis of sinus tarsi ligament of ankle / 医疗卫生装备

Objective To compare the values of 3D-SPACE sequence and 2D-TSE sequence for displaying the anatomical details of the sinus tarsi ligament of the ankle.Methods 1.5T Siemens Auanto MRI scanner and 8-channel skull phased array coil were used for the examination of 26 healthy volunteers with 3D-SPACE three-dimensional isotropic sectional scanning as well as 2D-T1WI-TSE transverse and 2D-T2WI-TSE coronal sagittal two-dimensional fast spin echo scan.Two senior MRI radiologists evaluated the display rates of the two sequences for the cervical ligament of sinus tarsi and talus ligament so as to determine the values of the two sequences for displaying the cervical ligament of sinus tarsi.Results 3D-SPACE sequence behaved significantly better than 2D sequence when used to display the sinus tarsi ligament (P＜0.05),and the display rates were statistically different at different positions (P＜0.05).3D-SPACE sequence gained obvious advantages over 2D conventional TSE sequence when used to display the cervical ligament of sinus tarsi and talus ligament,and the highest display rate occurred in case of the cervical ligament of sinus tarsi scanned with 3D-SPACE coronal view and in case of the talus ligament scanned at coronal and sagittal positions.Conclusion 3D-SPACE sequence can display clearly the anatomical details of the sinus tarsi ligament with multiplanar reconstruction,curved planar reformation and etc,and thus is worthy promoting clinically.

Comparative study of MR 3D-SPACE,3D-True FISP and 2D-FSE-PD sequences in articular cartilage of the knee joint / 实用放射学杂志

Objective To compare the imaging quality of articular cartilage of the knee with 3D-sampling perfection with applica-tion optimized contrast using different flip angle evolutions (3D-SPACE),3D-true fast imaging with steady-state precession (3D-True FISP)and 2D-fast-spin-echo-proto-density(2D-FSE-PD)sequences.Methods 40 healthy volunteers and 20 patients of knee joints were examined with 3D-SPACE,3D-True FISP and 2D-FSE-PD sequences at 1.5T MRI.Signal-noise ratio (SNR),contrast-to-noise ratio (CNR)and lesion visualization of articular cartilage were compared.Results 3D-SPACE showed the highest SNR of cartilage and CNR of fluid/cartilage among the three sequences (P <0.05).3D-SPACE had the better capability for showing the lev-el I 、level Ⅱcartilage injury comparing with 3D-True FISP,but no significant difference between the cartilage injury at level Ⅲ and level Ⅳ.For all levels of cartilage injury,3D sequence was better than the 2D sequence.Conclusion Compared with the 3D-True FISP sequence and 2D-FSE-PD sequence,3D-SPACE sequence can show the structure of knee and knee cartilage injury better.

Herniation of spinal cord into nerve root avulsion pseudomeningocele: A rare cause of delayed progressive neurological deficit.

We present a patient with old traumatic right brachial plexus injury, who developed progressive neurological deterioration 4 years after the initial injury. On magnetic resonance imaging (MRI), herniation of the upper dorsal cord was noted into a post-traumatic pseudomeningocele. Though the herniation of cord into a post-traumatic pseudomeningocele is very rare, it should be suspected in cases of delayed progressive myelopathy. A three dimensional (3-D) T2-weighted sequence such as Sampling Perfection with Application optimized Contrasts using different flip angle Evolution (SPACE) or constructive interference in steady state (CISS) provides optimal visualization of the herniated cord and helps in surgical planning.

Discussion on the application of 3D SPACE sequence to display normal brachial plexus / 中国医学装备

Objective: To investigate the value of enhanced 3D SPACE sequence in displaying brachial plexus. Methods:35 healthy volunteers with no history of brachial plexus injury of brachial plexus MRI examinations by DWIBS scan, and SPACE scanned. Analysis and comparison of DWIBS sequences, sequences of SPACE provides a clear display of the brachial plexus, and two sets of image sequence average signal-to-noise ratio (SNR) and the contrast to noise ratio (CNR). Results:A total of 35 cases 70 lateral brachial plexus after coronary DWIBS is clearly displayed on the sequence;the partial medial cord of brachial plexus, beams and lateral beams can also be displayed in the SPACE sequence. SPACE sequence of image signal-to-noise ratio and contrast noise ratio than the DWIBS sequence, and the difference is statistically significant. Conclusion:SPACE sequence can clearly show the brachial plexus, and DWIBS sequences compared to the normal image has a higher resolution of the brachial plexus.