Visualization of deglutition and gastroesophageal reflux using real-time MRI: a standardized approach to image acquisition and assessment.

This study aims to develop a standardized algorithm for gastroesophageal image acquisition and diagnostic assessment using real-time MRI. Patients with GERD symptoms undergoing real-time MRI of the esophagus and esophagogastric junction between 2015 and 2018 were included. A 10 ml bolus of pineapple juice served as an oral contrast agent. Patients performed Valsalva maneuver to provoke reflux and hiatal hernia. Systematic MRI assessment included visual presence of achalasia, fundoplication failure in patients with previous surgical fundoplication, gastroesophageal reflux, and hiatal hernia. A total of 184 patients (n = 92 female [50%], mean age 52.7 ± 15.8 years) completed MRI studies without adverse events at a mean examination time of 15 min. Gastroesophageal reflux was evident in n = 117 (63.6%), hiatal hernia in n = 95 (52.5%), and achalasia in 4 patients (2.2%). Hiatal hernia was observed more frequently in patients with reflux at rest (n = 67 vs. n = 6, p < 0.01) and during Valsalva maneuver (n = 87 vs. n = 8, p < 0.01). Real-time MRI visualized a morphologic correlate for recurring GERD symptoms in 20/22 patients (90%) after fundoplication procedure. In a large-scale single-center cohort of patients with GERD symptoms undergoing real-time MRI, visual correlates for clinical symptoms were evident in most cases. The proposed assessment algorithm could aid in wider-spread utilization of real-time MRI and provides a comprehensive approach to this novel imaging modality.

T1 mapping of the prostate using Single-Shot T1FLASH and MOLLI MRI Techniques: Comparison of artifact burden and image quality.

PURPOSE: To assess artifact burden and image quality of different MRI T1 mapping techniques of the prostate. METHODS: Participants with suspected prostate cancer (PCa) were prospectively enrolled from June-October 2022 and examined with multiparametric prostate MRI (mpMRI; 3 T scanner; T1wi, T2wi, DWI und DCE). T1 mapping was performed before and after administration of gadolinium-based contrast-agent (GBCA) using (i) a modified Look-Locker inversion (MOLLI) technique and (ii) a novel single-shot T1FLASH inversion recovery technique. T2wi, DWI, T1FLASH and MOLLI sequences were systematically examined regarding prevalence of artifacts and image quality using a 5-point Likert-Scale. RESULTS: A total of n = 100 patients were included (median age: 68 years). T1FLASH maps (pre-and post-GBCA) showed metal artifacts in 7% of cases and susceptibility artifacts in 1%. For MOLLI maps, pre-GBCA metal and susceptibility artifacts were documented in 6.5% of cases each. MOLLI maps post-GBCA showed artifacts in 59% of cases resulting primarily from urinary GBCA excretion and GBCA accumulation at the bladder base (p < 0.01 versus T1FLASH post-GBCA). Image quality for T1FLASH pre-GBCA was rated at a mean 4.9+/-0.4 and for MOLLI at 4.8+/-0.6 (p = 0.14). Post-GBCA image quality was rated at a mean 4.9+/-0.4 for T1FLASH and at 3.7+/-1.1 for MOLLI (p < 0.001). CONCLUSIONS: T1FLASH maps provide a fast and robust method for quantification of T1 relaxation times of the prostate. T1FLASH is suitable for T1 mapping of the prostate following administration of contrast agents, while MOLLI T1 mapping is impaired through GBCA accumulation at the bladder base leading to severe image artifacts and reduced image quality.

T1 Mapping of the Prostate Using Single-Shot T1FLASH: A Clinical Feasibility Study to Optimize Prostate Cancer Assessment.

PURPOSE: The aim of this study was to assess the clinical feasibility of magnetic resonance imaging (MRI) T1 mapping using T1FLASH for assessment of prostate lesions. METHODS: Participants with clinical suspicion for prostate cancer (PCa) were prospectively enrolled between October 2021 and April 2022 with multiparametric prostate MRI (mpMRI) acquired on a 3 T scanner. In addition, T1 mapping was accomplished using a single-shot T1FLASH technique with inversion recovery, radial undersampling, and iterative reconstruction. Regions of interest (ROIs) were manually placed on radiologically identified prostate lesions and representative reference regions of the transitional zone (TZ), benign prostate hyperplasia nodules, and peripheral zone (PZ). Mean T1 relaxation times and apparent diffusion coefficient (ADC) values (b = 50/b = 1400 s/mm 2 ) were measured for each ROI. Participants were included in the study if they underwent ultrasound/MRI fusion-guided prostate biopsy for radiologically or clinically suspected PCa. Histological evaluation of biopsy cores served as reference standard, with grading of PCa according to the International Society of Urological Pathology (ISUP). ISUP grades 2 and above were considered clinically significant PCa for the scope of this study. Histological results of prostate biopsy cores were anatomically mapped to corresponding mpMRI ROIs using biopsy plans. T1 relaxation times and ADC values were compared across prostate regions and ISUP groups. Across different strata, T1 relaxation time, ADC values, and diagnostic accuracy (area under the curve [AUC]) were compared using statistical methods accounting for clustered data. RESULTS: Of 67 eligible participants, a total of 40 participants undergoing ultrasound/MRI fusion-guided prostate biopsy were included. Multislice T1 mapping was successfully performed in all participants at a median acquisition time of 2:10 minutes without evident image artifacts. A total of 71 prostate lesions was radiologically identified (TZ 49; PZ 22). Among those, 22 were histologically diagnosed with PCa (ISUP groups 1/2/3/4 in n = 3/15/3/1 cases, respectively). In the TZ, T1 relaxation time was statistically significantly lower for PCa compared with reference regions ( P = 0.029) and benign prostate hyperplasia nodules ( P < 0.001). Similarly, in the PZ, PCa demonstrated shorter T1 relaxation times versus reference regions ( P < 0.001). PCa also showed a trend toward shorter T1 relaxation times (median, 1.40 seconds) compared with radiologically suspicious lesions with benign histology (median, 1.47 seconds), although statistical significance was not reached ( P = 0.066). For discrimination of PCa from reference regions and benign prostate lesions, T1 relaxation times and ADC values demonstrated AUC = 0.80 and AUC = 0.83, respectively ( P = 0.519). Discriminating PCa from radiologically suspicious lesions with benign histology, T1 relaxation times and ADC values showed AUC = 0.69 and AUC = 0.62, respectively ( P = 0.446). CONCLUSIONS: T1FLASH-based T1 mapping yields robust results for quantification of prostate T1 relaxation time at a short examination time of 2:10 minutes without evident image artifacts. Associated T1 relaxation times could aid in discrimination of significant and nonsignificant PCa. Further studies are warranted to confirm these results in a larger patient cohort, to assess the additional benefit of T1FLASH maps in conjunction with mpMRI sequences in the setting of deep learning, and to evaluate the robustness of T1FLASH maps compared with potentially artifact-prone diffusion-weighted imaging sequences.

Comparing Apparent Diffusion Coefficient and FNCLCC Grading to Improve Pretreatment Grading of Soft Tissue Sarcoma-A Translational Feasibility Study on Fusion Imaging.

Histological subtype and grading are cornerstones of treatment decisions in soft tissue sarcoma (STS). Due to intratumoral heterogeneity, pretreatment grading assessment is frequently unreliable and may be improved through functional imaging. In this pilot study, 12 patients with histologically confirmed STS were included. Preoperative functional magnetic resonance imaging was fused with a computed tomography scan of the resected specimen after collecting core needle biopsies and placing radiopaque markers at distinct tumor sites. The Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) grading criteria of the biopsies and apparent diffusion coefficients (ADCs) of the biopsy sites were correlated. Concordance in grading between the specimen and at least one biopsy was achieved in 9 of 11 cases (81.8%). In 7 of 12 cases, fusion imaging was feasible without relevant contour deviation. Functional analysis revealed a tendency for high-grade regions (Grade 2/3 (G2/G3)) (median (range) ± standard deviation: 1.13 (0.78-1.70) ± 0.23 × 10-3 mm2/s) to have lower ADC values than low-grade regions (G1; 1.43 (0.64-2.03) ± 0.46 × 10-3 mm2/s). In addition, FNCLCC scoring of multiple tumor biopsies proved intratumoral heterogeneity as expected. The ADC appears to correlate with the FNCLCC grading criteria. Further studies are needed to determine whether functional imaging may supplement histopathological grading.

Evidence of Two Novel LAMA2 Variants in a Patient With Muscular Dystrophy: Facing the Challenges of a Certain Diagnosis.

Background: Benefits and challenges resulting from advances in genetic diagnostics are two sides of the same coin. Facilitation of a correct and timely diagnosis is paralleled by challenges in interpretation of variants of unknown significance (VUS). Focusing on an individual VUS-re-classification pipeline, this study offers a diagnostic approach for clinically suspected hereditary muscular dystrophy by combining the expertise of an interdisciplinary team. Methods: In a multi-step approach, a thorough phenotype assessment including clinical examination, laboratory work, muscle MRI and histopathological evaluation of muscle was performed in combination with advanced Next Generation Sequencing (NGS). Different in-silico tools and prediction programs like Alamut, SIFT, Polyphen, MutationTaster and M-Cap as well as 3D- modeling of protein structure and RNA-sequencing were employed to determine clinical significance of the LAMA2 variants. Results: Two previously unknown sequence alterations in LAMA2 were detected, a missense variant was classified initially according to ACMG guidelines as a VUS (class 3) whereas a second splice site variant was deemed as likely pathogenic (class 4). Pathogenicity of the splice site variant was confirmed by mRNA sequencing and nonsense mediated decay (NMD) was detected. Combination of the detected variants could be associated to the LGMDR23-phenotype based on the MRI matching and literature research. Discussion: Two novel variants in LAMA2 associated with LGMDR23-phenotype are described. This study illustrates challenges of the genetic findings due to their VUS classification and elucidates how individualized diagnostic procedure has contributed to the accurate diagnosis in the spectrum of LGMD.

Effectiveness of fourth-line dual immunotherapy in hepatocellular carcinoma with simultaneous steroid administration for immune-related hepatitis.

Medical therapy of advanced hepatocellular carcinoma (HCC) remains an emerging subject, but therapeutic sequences together with toxicity management are rarely described. Herein, we report the case of a therapeutic sequence and toxicity management in a 72-year old White male with advanced non-cirrhotic HCC. The HCC of this patient was refractory against treatment with several tyrosine kinase inhibitors, including lenvatinib and cabozantinib or immune combination of pembrolizumab and lenvatinib. Double immune combination of nivolumab and ipilimumab was effective in fourth-line treatment but resulted in immunotherapy-related grade 4 hepatitis. This toxicity responded well to high doses of corticosteroids, and reinduction of dual immune combination remained effective despite continuation of high-dose corticosteroids in a non-cirrhotic HCC. This case demonstrated the efficacy of double immune therapy in higher treatment lines in advanced non-cirrhotic HCC even if the patient was treated with other immune modulatory therapies earlier. Moreover, it can remain effective under concomitant administration of high-dose corticosteroids.

Endoscopic internal drainage and low negative-pressure endoscopic vacuum therapy for anastomotic leaks after oncologic upper gastrointestinal surgery.

BACKGROUND: Endoscopic internal drainage (EID) with double-pigtail stents or low negative-pressure endoscopic vacuum therapy (EVT) are treatment options for leakage after upper gastrointestinal oncologic surgery. We aimed to compare the effectiveness of these techniques. METHODS: Between 2016 and 2019, patients treated with EID in five centers in France and with EVT in Göttingen, Germany were included and retrospectively analyzed using univariate analysis. Pigtail stents were changed every 4 weeks; EVT was repeated every 3-4 days until leak closure. RESULTS: 35 EID and 27 EVT patients were included, with a median (interquartile range [IQR]) leak size of 0.75 cm (0.5-1.5). Overall treatment success was 100 % (95 % confidence interval [CI] 90 %-100 %) for EID vs. 85.2 % (95 %CI 66.3 %-95.8 %) for EVT (P = 0.03). The median (IQR) number of endoscopic procedures was 2 (2-3) vs. 3 (2-6.5; P = 0.003) and the median (IQR) treatment duration was 42 days (28-60) vs. 17 days (7.5-28; P < 0.001), for EID vs. EVT, respectively. CONCLUSION: EID and EVT provide high closure rates for upper gastrointestinal anastomotic leaks. EVT provides a shorter treatment duration, at the cost of a higher number of procedures.

Liver metastasis mimicking a liver cyst of a thymoma in a 38-year-old immunocompromised patient.

Cystic liver lesions (CLL) are common and, in the majority of cases, benign. However, the range of differential diagnoses of CLL is wide. A combination of medical history, blood test results, and imaging can help find the correct diagnosis. We report the case of a 38-year-old immunocompromised female patient with a history of thymectomy and postoperative radiation 3 years prior due to thymoma. Subsequently, the patient was referred to our department for clarification of a cystic liver lesion. During short-term follow-up, the lesion increased in size, and due to the contrast agent behavior in the ultrasound and MRI examination, the suspicion of a biliary cystadenocarcinoma was considered.Furthermore, imaging showed several subcentimetric liver lesions of unknown dignity. Finally, pericystectomy and atypical partial liver resection was performed. Histology revealed a cystic metastasis of the malignant B3 thymoma and a cavernous hemangioma. Liver metastases of a thymoma are rare, and this is the first case of a cystic liver metastasis of a thymoma. The presented case illustrates that in the management of CLLs beside imaging techniques, the medical history with previous conditions should be considered, especially in past malignancies.

Surgical treatment of metastatic VIPoma: a case report.

VIPoma, a neuroendocrine tumour mostly occurring in the human pancreas and producing high levels of vasoactive intestinal peptide, is a rare disease that presents with a wide spectrum of symptoms, including intense diarrhoea, hypokalaemia, and cardiac complications, with life-threatening consequences. In most cases, metastatic lesions are present at VIPoma diagnosis. Treatment options include symptomatic therapy, chemotherapy, radiation and surgery. Due to its low incidence, there are no evidence-based therapy recommendations to date. Here, we present a case of a 39-year-old woman with severe symptoms due to VIPoma of the pancreas with diffuse hepatic metastasis, who underwent simultaneous resection of the primary tumour, extensive liver resection and radiofrequency ablation. The patient was released in good health and was recurrence-free during 12 months surveillance. According to the existing literature and our own experience, surgical procedures appear to be the most promising therapy option for cases with diffuse hepatic metastasis, offering patients relief from their symptoms and (chemo)therapy-free time.

Systemic IgG4-Related Disease Masquerading as Cholangiocarcinoma: A Case Report Underscoring the Importance of Medical History.

BACKGROUND Immunoglobulin (Ig) G4-related disease is a rare disease of unknown pathophysiology, which can affect multiple organs leading to tissue fibrosis and organ failure. The present case report describes a patient with systemic IgG4-related disease (IgG4-RD) that occurred over a 1-year period and affected multiple organs at different times. Imaging studies, interventional procedures, changes in laboratory parameters, and histopathology demonstrate the novel and known aspects of this disease before and during prednisolone monotherapy and in combination with azathioprine. CASE REPORT A 64-year-old man presented with weight loss and painless jaundice, which was highly suspicious for cholangiocarcinoma. A thorough medical history together with laboratory tests, imaging procedures, and endoscopic interventions confirmed that surgery was not needed and led to the final diagnosis of histologically-confirmed, IgG4-related sclerosing cholangitis and autoimmune pancreatitis type 1. Other typical organ manifestations of systemic IgG4-RD were diagnosed through a thorough medical review, which led to immunohistochemical reevaluation of past surgical specimens. Besides the IgG4-related organ manifestations, which can include periorbital xanthelasmas, our patient developed a pulmonary adenocarcinoma 6 years after the initial clinical onset of IgG4-RD. After immunosuppressive treatment with prednisolone alone and subsequently in combination with azathioprine, the patient's IgG4-RD resolved. CONCLUSIONS Interdisciplinary collaboration is required to diagnose IgG4-RD that involves multiple organs. Patient medical history remains crucial for diagnosis and attention should be paid to avoiding unnecessary surgery. Tumors (lung adenocarcinomas) and xanthelasmas can develop because of IgG4-RD. Glucocorticoids and additional azathioprine may be advisable for maintenance treatment.

EMR + with the AWC improves endoscopic resection speed compared to ESD: a porcine ex-vivo pilot study.

INTRODUCTION: To improve resection speed and to reach higher en bloc resection rates in lesions ≥ 2 cm, a novel grasp and snare EMR technique termed "EMR+", accomplished by an additional working channel (AWC), was developed. Its use compared to endoscopic submucosal dissection (ESD) is evaluated for the first time. MATERIAL AND METHODS: We prospectively conducted a randomized pre-clinical ex-vivo pilot study in explanted porcine stomachs for the comparison of EMR + with classical ESD of mucosal-based lesions. Prior to intervention, we set flat lesions with a standardized size of 3 × 3 cm. RESULTS: The median time of procedure was significantly shorter in the EMR + group (median 10.5 min, range 4.4-24 min) than in the ESD group (median 32 min, range 14-61.6 min, p < .0001). The rate of en bloc resection was significantly lower in the EMR + group (38 % vs. 95 %) (p < .0001). Nevertheless, an improvement in the learning curve for EMR + was achieved after the first 12 procedures, with a subsequent en bloc resection rate of 100 %. CONCLUSIONS: EMR + could improve the efficiency of mucosal resection procedures. Initial experience demonstrates a higher and satisfactory en bloc resection rate after going through the learning curve of EMR+.

Impact of Endoscopic Vacuum Therapy with Low Negative Pressure for Esophageal Perforations and Postoperative Anastomotic Esophageal Leaks.

INTRODUCTION: Management of esophageal anastomotic leaks (AL) and esophageal perforations (EP) remains difficult and often requires an interdisciplinary treatment modality. For primary endoscopic management, self-expanding metallic stent (SEMS) placement is often considered first-line therapy. Recently, endoscopic vacuum therapy (EVT) has emerged as an alternative or adjunct for management of these conditions. So far, data for EVT in the upper gastrointestinal-tract is restricted to single centre, non-randomized trials. No studies on optimal negative pressure application during EVT exist. The aim of our study is to describe our centre's experience with low negative pressure (LNP) EVT for these indications over the past 5-years. PATIENTS AND METHODS: Between January 2014 and December 2018, 30 patients were endoscopically treated for AL (n = 23) or EP (n = 7). All patients were primarily treated with EVT and LNP between -20 and -50 mm Hg. Additional endoscopic treatment was added when EVT failed. Procedural and peri-procedural data, as well as clinical outcomes including morbidity and mortality, were analysed. RESULTS: Clinical successful endoscopic treatment of EP and AL was achieved in 83.3% (n = 25/30), with 73.3% success using EVT alone (n = 22/30). Mean treatment duration until leak closure was 16.1 days (range 2-58 days). Additional treatment modalities for complete leak resolution was necessary in 10% (n = 3/30), including SEMS placement and fibrin glue injection. Mean hospital stay for patients with EP was shorter with 33.7 days compared to AL with 54.4 days (p = 0.08). Estimated preoperative 10-year overall survival (Charlson comorbidity score) was 39.4% in patients with AL and 59.9% in patients with EP (p = 0.26). A mean of 5.1 EVT changes (range 1-12) was needed in EP and 3.6 changes (range 1-13) in AL to achieve complete closure, switch to other treatment modality, or reach endoscopic failure (p = 0.38). CONCLUSION: LNP EVT enables effective minimally - invasive endoluminal leak closure from anastomotic esophageal leaks and EP in high-morbid patients. In this study, EVT was combined with other endoscopic treatment options such as SEMS placement or fibrin glue injection in order to achieve leak or perforation closure in the vast majority of patients (83.3%). Low aspiration pressures led to slower but still sufficient clinical results.

Cross-insitutional standardization of imaging protocols - A pilot study within the scope of the Comprehensive Cancer Center Lower Saxony. / Standortübergreifende Standardisierung von Untersuchungsprotokollen ­ eine Pilotstudie im Rahmen des Comprehensive Cancer Centers Niedersachen.

PURPOSE: Cross-institutional establishment of standardized protocols for CT and MR imaging of primary liver and pancreas tumors in an oncological center. MATERIALS AND METHODS: This prospective dual-institution study was approved by the local IRBs. Minimum requirements (phases, sequences, slice thickness) for imaging of primary liver and pancreas tumors were defined and implemented at both sites. Between 06/19 and 08/19 in-house examinations were evaluated in terms of compliance with defined protocols and image quality. In addition, extramural examinations that were demonstrated at interdisciplinary tumor board meetings in the same study period were reviewed. Results were analyzed by means of descriptive statistics, and differences between centers, modalities and organs assessed (Fisher-exact Test, p < 0.05 deemed significant). RESULTS: 480 data sets (397 internal, 83 extramural) were included in this study and analyzed. Overall protocol compliance for in-house examinations was 93.5 % (371/397 datasets), without statistical significant difference between the two institutions (p = 0.0615). External studies met minimum requirements in 48.2 % (40/83 datasets). Regarding in-house imaging, significant differences were observed between CT of the liver and the pancreas (p < 0.05) and between CT and MRI of the pancreas (p < 0.05). CONCLUSION: As demonstrated in this pilot project, cross-institutional establishment of standardized imaging protocols is feasible with a compliance rate of more than 90 %. Standardized imaging protocols may serve as a quality indicator in oncological imaging, and over time, improve cross-institutional patient care. KEY POINTS: · Cross-institutional establishment of standardized imaging protocols is feasible with high compliance.. · Standards may serve as a quality indicator in oncological imaging.. · In perspective, cross-institutional patient care may be improved.. CITATION FORMAT: · Römermann I, Al-Bourini O, Seif Amir Hosseini A et al. Cross-insitutional standardization of imaging protocols - A pilot study within the scope of the Comprehensive Cancer Center Lower Saxony. Fortschr Röntgenstr 2021; 193: 410 - 416.

Future liver remnant growth after various portal vein embolization regimens: a quantitative comparison.

Purpose: To compare the efficacy of right portal vein embolization using ethylene vinyl alcohol (EVOH-PVE) compared to other embolic agents and surgical right portal vein ligation (PVL).Material and methods: Patients with right sided liver malignancies scheduled for extensive surgery and receiving induction of liver hypertrophy via right portal vein embolization/ligature between 2010-2016 were retrospectively evaluated. Treatments included were ethylene vinyl alcohol copolymer (Onyx®, EVOH-PVE), ethiodized oil (Lipiodol®, Lipiodol/PVA-PVE), polyvinyl alcohol (PVA-PVE) or surgical ligature (PVL). Liver segments S2/3 were used to assess hypertrophy. Primary outcome was future liver remnant growth in ml/day.Results: Forty-one patients were included (EVOH-PVE n = 11; Lipiodol/PVA-PVE n = 10; PVA-PVE n = 8; PVL n = 12), the majority presenting with cholangiocarcinoma and colorectal metastases (n = 11; n = 27). Pre-interventional liver volumes were comparable (p = .095). Liver hypertrophy was successfully induced in all but one patient receiving Lipiodol/PVA-PVE. Liver segment S2/3 growth was largest for EVOH-PVE (5.38 ml/d) followed by PVA-PVE (2.5 ml/d), with significantly higher growth rates than PVL (1.24 ml/d; p < .001; p = .007). No significant difference was evident for Lipiodol/PVA-PVE (1.43 ml/d, p = .809).Conclusions: Portal vein embolization using EVOH demonstrates fastest S2/3 growth rates compared to other embolic agents and PVL, potentially due to its permanent portal vein embolization and induction of hepatic inflammation.

[Challenges in diagnostics for intestinal tuberculosis - Pitfalls of a forgotten infectious disease: case series and literature review]. / Herausforderungen in der Diagnostik der Darmtuberkulose ­ Pitfalls einer vergessenen infektiösen Erkrankung: Eine Fallserie und Literaturübersicht.

Intestinal tuberculosis is an infectious disease of the extrapulmonary manifestation with the Mycobacteria tuberculosis complex. In developed countries, this disease is rarely seen. The clinical features are heterogeneous and unspecific. Furthermore, intestinal tuberculosis poses diagnostic challenges. Regarding intestinal tuberculosis the Ziehl-Neelsen staining for acid-fast bacillus, PCR examination and culture methods show only poor sensitivity and specificity. In this case series, we present three patients suffering from intestinal tuberculosis, who were diagnosed and treated successfully. Furthermore, we review the literature about the pitfalls of the diagnostic approaches and the treatment options of intestinal tuberculosis.

Hiatal hernias in patients with GERD-like symptoms: evaluation of dynamic real-time MRI vs endoscopy.

PURPOSE: To assess the diagnostic potential of real-time MRI for assessment of hiatal hernias in patients with GERD-like symptoms compared to endoscopy. MATERIAL AND METHODS: One hundred eight patients with GERD-like symptoms were included in this observational cohort study between 2015 and 2017. Real-time MRI was performed at 3.0 Tesla with temporal resolution of 40 ms, dynamically visualizing the esophageal transport of a pineapple juice bolus, its passage through the gastroesophageal junction, and functional responses during Valsalva maneuver. Hernia detection on MRI and endoscopy was calculated using contingency tables with diagnosis of hernia on either modality as reference. RESULTS: Of 108 patients, 107 underwent successful MRI without adverse events; 1 examination was aborted to inability to swallow pineapple juice in supine position. No perforation or acute bleeding occurred during endoscopy. Median examination time was 15 min. Eighty-five patients (79.4%) were diagnosed with hiatal hernia on either real-time MRI or endoscopy. Forty-six hernias were visible on both modalities. Seventeen hernias were evident exclusively on MRI, and 22 exclusively on endoscopy. Sixteen of the 63 MRI-detected hernias (25.4%) were detectable only during Valsalva maneuver, which were smaller compared to hernias at rest (median - 13.5 vs - 33.0 mm, p < 0.001). Diagnostic accuracy for hernia detection was comparable for MRI and endoscopy (sensitivity 74% vs 80%, p = 0.4223; specificity 100% vs 100%, p > 0.99). CONCLUSION: Real-time MRI is a fast and safe modality for assessment of the gastroesophageal junction, without radiation exposure or administration of gadolinium-based contrast media. Although MRI and endoscopy yield comparable diagnostic accuracy, dynamic MRI sequences are able to visualize hiatal hernias that were occult on static MRI sequences or endoscopy in a relevant number of cases. KEY POINTS: • Real-time MRI is a safe and fast imaging modality for examination of the gastroesophageal junction, combining anatomical and functional information for enhanced detection of hiatal hernias. • Real-time MRI and endoscopy yield comparably high diagnostic accuracy: real-time MRI visualizes hiatal hernias that were occult on endoscopy in a relevant number of patients; however, several hiatal hernias detected on endoscopy were occult on real-time MRI. • There is clinical potential of real-time MR imaging in patients with GERD-like symptoms and equivocal findings on endoscopy or pH-metry, for anatomical visualization in patients planned for surgical intervention, or those with suspected fundoplication failures.

Diffusion-weighted MRI of the prostate without susceptibility artifacts: Undersampled multi-shot turbo-STEAM with rotated radial trajectories.

The aim of this study was to develop and evaluate a clinically feasible approach to diffusion-weighted (DW) MRI of the prostate without susceptibility-induced artifacts. The proposed method relies on an undersampled multi-shot DW turbo-STEAM sequence with rotated radial trajectories and a multi-step inverse reconstruction with denoised multi-shot phase maps. The total acquisition time was below 6 min for a resolution of 1.4 × 1.4 × 3.5 mm3 and six directions at b = 600 s mm-2 . Studies of eight healthy subjects and two patients with prostate cancer were performed at 3 T employing an 18-channel body-array coil and elements of the spine coil. The method was compared with conventional DW echo-planar imaging (EPI) of the prostate. The results confirm that DW STEAM MRI avoids geometric distortions and false image intensities, which were present for both single-shot EPI (ssEPI) and readout-segmented EPI, particularly near the intestinal wall of the prostate. Quantitative accuracy of the apparent diffusion coefficient (ADC) was validated with use of a numerical phantom providing ground truth. ADC values in the central prostate gland of healthy subjects were consistent with those measured using ssEPI and with literature data. Preliminary results for patients with prostate cancer revealed a correct anatomical localization of lesions with respect to T2 -weighted MRI in both mean DW STEAM images and ADC maps. In summary, DW STEAM MRI of the prostate offers clinically relevant advantages for the diagnosis of prostate cancer compared with state-of-the-art EPI-based approaches. The method warrants extended clinical trials.

Real-time MRI for the dynamic assessment of fundoplication failure in patients with gastroesophageal reflux disease.

PURPOSE: To assess the diagnostic potential of dynamic real-time MRI for fundoplication failure in patients with persistent or recurrent GERD-like (gastroesophageal reflux disease) complaints. MATERIAL AND METHODS: Twenty-two consecutive patients (male n = 11; female n = 11; median age 59 years) with recurrent or persistent GERD-like symptom after fundoplication were enrolled between 2015 and 2017. Median duration of GERD-like symptoms was 21 months. Real-time MRI (3 Tesla) was performed at 40 ms temporal resolution using undersampled radial fast low-angle shot acquisitions with nonlinear inverse image reconstruction. MRI movies dynamically visualized bolus transit of pineapple juice through the gastroesophageal junction, position of the fundoplication wrap and recurring hernia or reflux during Valsalva maneuver. MRI results were compared to endoscopic findings. RESULTS: Real-time MRI was successfully completed in all patients without adverse events (average examination time 15 min). Morphological correlates for GERD-like symptoms were evident in 20 patients (90.1%) with gastric reflux in 19 cases. Nine patients (40.1%) had wrap disruption and recurrent gastric hernia. Wrap migration or telescoping hernia was detected in nine patients (40.1%). One patient presented with continued reflux despite intact fundoplication wrap. Esophageal dysmotility with delayed bolus passage was observed in one case. On endoscopy, gastric hernia or wrap disruption was diagnosed in seven cases, and esophagitis or Barret's metaplasia in nine cases. CONCLUSION: Real-time MRI is a fast and safe modality for dynamic imaging after fundoplication, without radiation exposure or administration of gadolinium-based contrast media. In a relevant number of cases, real-time MRI reveals correlates for GERD-like symptoms. KEY POINTS: • Real-time MRI reliably visualizes the gastroesophageal junction after fundoplication surgery. • Patients with recurring GERD-like symptoms have a high rate of morphological failure patterns that can be identified by real-time MRI. • Dynamic assessment of gastroesophageal junction by real-time MRI is a perspective diagnostic tool for detection of fundoplication failure.