Background & Aims The prevalence of pancreatic cysts is not known, but asymptomatic pancreatic cysts are diagnosed with increasing frequency. We investigated the prevalence of pancreatic cysts in ...individuals who were screened by magnetic resonance imaging (MRI) as part of a preventive medical examination. Methods Data from consecutive persons who underwent abdominal MRI (n = 2803; 1821 men; mean age, 51.1 ± 10.8 y) at an institute of preventive medical care were included from a prospective database. All individuals had completed an application form including questions about possible abdominal complaints and prior surgery. MRI reports were reviewed for the presence of pancreatic cysts. Original image sets of all positive MRI reports and a representative sample of the negative series were re-assessed by a blinded, independent radiologist. Results Pancreatic cysts were reported in 66 persons (2.4%; 95% confidence interval, 1.9–3.0); prevalence correlated with increasing age ( P < .001). There was no difference in prevalence between sexes ( P = .769). There was no correlation between abdominal complaints and the presence of pancreatic cysts ( P = .542). Four cysts (6%) were larger than 2 cm and 3 (5%) were larger than 3 cm. Review of the original image sets by the independent radiologist did not significantly change these findings. Conclusions The prevalence of pancreatic cysts in a large consecutive series of individuals who underwent an MRI at a preventive medical examination was 2.4%. Prevalence increased with age, but did not differ between sexes. Only a minority of cysts were larger than 2 cm.
Increased neurofilament levels in biofluids are commonly used as a proxy for neurodegeneration in several neurodegenerative disorders. In this study, we aimed to investigate the distribution of ...neurofilaments in the cerebral cortex of Parkinson's disease (PD), PD with dementia (PDD) and dementia with Lewy bodies (DLB) donors, and its association with pathology load and MRI measures of atrophy and diffusivity.
Using a within-subject post-mortem MRI-pathology approach, we included 9 PD, 12 PDD/DLB and 18 age-matched control donors. Cortical thickness and mean diffusivity (MD) metrics were extracted respectively from 3DT1 and DTI at 3T in-situ MRI. After autopsy, pathological hallmarks (pSer129-αSyn, p-tau and amyloid-β load) together with neurofilament light-chain (NfL) and phosphorylated-neurofilament medium- and heavy-chain (p-NfM/H) immunoreactivity were quantified in seven cortical regions, and studied in detail with confocal-laser scanning microscopy. The correlations between MRI and pathological measures were studied using linear mixed models.
Compared to controls, p-NfM/H immunoreactivity was increased in all cortical regions in PD and PDD/DLB, whereas NfL immunoreactivity was increased in the parahippocampal and entorhinal cortex in PDD/DLB. NfL-positive neurons showed degenerative morphological features and axonal fragmentation. The increased p-NfM/H correlated with p-tau load, and NfL correlated with pSer129-αSyn but more strongly with p-tau load in PDD/DLB. Lastly, neurofilament immunoreactivity correlated with cortical thinning in PD and with increased cortical MD in PDD/DLB.
Taken together, increased neurofilament immunoreactivity suggests underlying axonal injury and neurofilament accumulation in morphologically altered neurons with increased pathological burden. Importantly, we demonstrate that such neurofilament markers at least partly explain MRI measures that are associated with the neurodegenerative process.
CT perfusion (CTP) analysis is difficult to implement in clinical practice. Therefore, we investigated a novel semi-automated CTP AI biomarker and applied it to identify vascular phenotypes of ...pancreatic ductal adenocarcinoma (PDAC) and evaluate their association with overall survival (OS).
From January 2018 to November 2022, 107 PDAC patients were prospectively included, who needed to undergo CTP and a diagnostic contrast-enhanced CT (CECT). We developed a semi-automated CTP AI biomarker, through a process that involved deformable image registration, a deep learning segmentation model of tumor and pancreas parenchyma volume, and a trilinear non-parametric CTP curve model to extract the enhancement slope and peak enhancement in segmented tumors and pancreas. The biomarker was validated in terms of its use to predict vascular phenotypes and their association with OS. A receiver operating characteristic (ROC) analysis with five-fold cross-validation was performed. OS was assessed with Kaplan-Meier curves. Differences between phenotypes were tested using the Mann-Whitney U test.
The final analysis included 92 patients, in whom 20 tumors (21%) were visually isovascular. The AI biomarker effectively discriminated tumor types, and isovascular tumors showed higher enhancement slopes (2.9 Hounsfield unit HU/s vs. 2.0 HU/s,
< 0.001) and peak enhancement (70 HU vs. 47 HU,
< 0.001); the AUC was 0.86. The AI biomarker's vascular phenotype significantly differed in OS (
< 0.01).
The AI biomarker offers a promising tool for robust CTP analysis. In PDAC, it can distinguish vascular phenotypes with significant OS prognostication.
Abstract Objectives To assess 3-Tesla (3-T) ultra-small superparamagnetic iron oxide (USPIO)-enhanced MRI in detecting lymph node (LN) metastases for resectable adenocarcinomas of the pancreas, ...duodenum, or periampullary region in a node-to-node validation against histopathology. Methods Twenty-seven consecutive patients with a resectable pancreatic, duodenal, or periampullary adenocarcinoma were enrolled in this prospective single expert centre study. Ferumoxtran-10-enhanced 3-T MRI was performed pre-surgery. LNs found on MRI were scored for suspicion of metastasis by two expert radiologists using a dedicated scoring system. Node-to-node matching from in vivo MRI to histopathology was performed using a post-operative ex vivo 7-T MRI of the resection specimen. Sensitivity and specificity were calculated using crosstabs. Results Eighteen out of 27 patients (median age 65 years, 11 men) were included in the final analysis (pre-surgery withdrawal n = 4, not resected because of unexpected metastases peroperatively n = 2, and excluded because of inadequate contrast-agent uptake n = 3). On MRI 453 LNs with a median size of 4.0 mm were detected, of which 58 (13%) were classified as suspicious. At histopathology 385 LNs with a median size of 5.0 mm were found, of which 45 (12%) were metastatic. For 55 LNs node-to-node matching was possible. Analysis of these 55 matched LNs, resulted in a sensitivity and specificity of 83% (95% CI: 36–100%) and 92% (95% CI: 80–98%), respectively. Conclusion USPIO-enhanced MRI is a promising technique to preoperatively detect and localise LN metastases in patients with pancreatic, duodenal, or periampullary adenocarcinoma. Clinical relevance statement Detection of (distant) LN metastases with USPIO-enhanced MRI could be used to determine a personalised treatment strategy that could involve neoadjuvant or palliative chemotherapy, guided resection of distant LNs, or targeted radiotherapy. Registration The study was registered on clinicaltrials.gov NCT04311047. https://clinicaltrials.gov/ct2/show/NCT04311047?term=lymph+node&cond=Pancreatic+Cancer&cntry=NL&draw=2&rank=1 . Key Points LN metastases of pancreatic, duodenal, or periampullary adenocarcinoma cannot be reliably detected with current imaging . This technique detected LN metastases with a sensitivity and specificity of 83% and 92%, respectively . MRI with ferumoxtran-10 is a promising technique to improve preoperative staging in these cancers .
Ultrahigh field magnetic resonance imaging (MRI) (≥ 7 T) has the potential to provide superior spatial resolution and unique image contrast. Apart from radiofrequency transmit inhomogeneities in the ...body at this field strength, imaging of the upper abdomen faces additional challenges associated with motion-induced ghosting artifacts. To address these challenges, the goal of this work was to develop a technique for high-resolution free-breathing upper abdominal MRI at 7 T with a large field of view. Free-breathing 3D gradient-recalled echo (GRE) water-excited radial stack-of-stars data were acquired in seven healthy volunteers (five males/two females, body mass index: 19.6-24.8 kg/m
) at 7 T using an eight-channel transceive array coil. Two volunteers were also examined at 3 T. In each volunteer, the liver and kidney regions were scanned in two separate acquisitions. To homogenize signal excitation, the time-interleaved acquisition of modes (TIAMO) method was used with personalized pairs of B
shims, based on a 23-s Cartesian fast low angle shot (FLASH) acquisition. Utilizing free-induction decay navigator signals, respiratory-gated images were reconstructed at a spatial resolution of 0.8 × 0.8 × 1.0 mm
. Two experienced radiologists rated the image quality and the impact of B
inhomogeneity and motion-related artifacts on multipoint scales. The images of all volunteers showcased effective water excitation and were accurately corrected for respiratory motion. The impact of B
inhomogeneity on image quality was minimal, underscoring the efficacy of the multitransmit TIAMO shim. The high spatial resolution allowed excellent depiction of small structures such as the adrenal glands, the proximal ureter, the diaphragm, and small blood vessels, although some streaking artifacts persisted in liver image data. In direct comparisons with 3 T performed for two volunteers, 7-T acquisitions demonstrated increases in signal-to-noise ratio of 77% and 58%. Overall, this work demonstrates the feasibility of free-breathing MRI in the upper abdomen at submillimeter spatial resolution at a magnetic field strength of 7 T.
A syndesmosis is defined as a fibrous joint in which two adjacent bones are linked by a strong membrane or ligaments. This definition also applies for the distal tibiofibular syndesmosis, which is a ...syndesmotic joint formed by two bones and four ligaments. The distal tibia and fibula form the osseous part of the syndesmosis and are linked by the distal anterior tibiofibular ligament, the distal posterior tibiofibular ligament, the transverse ligament and the interosseous ligament. Although the syndesmosis is a joint, in the literature the term syndesmotic injury is used to describe injury of the syndesmotic ligaments. In an estimated 1–11% of all ankle sprains, injury of the distal tibiofibular syndesmosis occurs. Forty percent of patients still have complaints of ankle instability 6 months after an ankle sprain. This could be due to widening of the ankle mortise as a result of increased length of the syndesmotic ligaments after acute ankle sprain. As widening of the ankle mortise by 1 mm decreases the contact area of the tibiotalar joint by 42%, this could lead to instability and hence early osteoarthritis of the tibiotalar joint. In fractures of the ankle, syndesmotic injury occurs in about 50% of type Weber B and in all of type Weber C fractures. However, in discussing syndesmotic injury, it seems the exact proximal and distal boundaries of the distal tibiofibular syndesmosis are not well defined. There is no clear statement in the Ashhurst and Bromer etiological, the Lauge‐Hansen genetic or the Danis‐Weber topographical fracture classification about the exact extent of the syndesmosis. This joint is also not clearly defined in anatomical textbooks, such as Lanz and Wachsmuth. Kelikian and Kelikian postulate that the distal tibiofibular joint begins at the level of origin of the tibiofibular ligaments from the tibia and ends where these ligaments insert into the fibular malleolus. As the syndesmosis of the ankle plays an important role in the stability of the talocrural joint, understanding of the exact anatomy of both the osseous and ligamentous structures is essential in interpreting plain radiographs, CT and MR images, in ankle arthroscopy and in therapeutic management. With this pictorial essay we try to fill the hiatus in anatomic knowledge and provide a detailed anatomic description of the syndesmotic bones with the incisura fibularis, the syndesmotic recess, synovial fold and tibiofibular contact zone and the four syndesmotic ligaments. Each section describes a separate syndesmotic structure, followed by its clinical relevance and discussion of remaining questions.
Purpose
To increase the effectiveness of respiratory gating in radial stack‐of‐stars MRI, particularly when imaging at high spatial resolutions or with multiple echoes.
Methods
Free induction decay ...(FID) navigators were integrated into a three‐dimensional gradient echo radial stack‐of‐stars pulse sequence. These navigators provided a motion signal with a high temporal resolution, which allowed single‐spoke binning (SSB): each spoke at each phase encode step was sorted individually to the corresponding motion state of the respiratory signal. SSB was compared with spoke‐angle binning (SAB), in which all phase encode steps of one projection angle were sorted without the use of additional navigator data. To illustrate the benefit of SSB over SAB, images of a motion phantom and of six free‐breathing volunteers were reconstructed after motion‐gating using either method. Image sharpness was quantitatively compared using image gradient entropies.
Results
The proposed method resulted in sharper images of the motion phantom and free‐breathing volunteers. Differences in gradient entropy were statistically significant (p = 0.03) in favor of SSB. The increased accuracy of motion‐gating led to a decrease of streaking artifacts in motion‐gated four‐dimensional reconstructions. To consistently estimate respiratory signals from the FID‐navigator data, specific types of gradient spoiler waveforms were required.
Conclusion
SSB allowed high‐resolution motion‐corrected MR imaging, even when acquiring multiple gradient echo signals or large acquisition matrices, without sacrificing accuracy of motion‐gating. SSB thus relieves restrictions on the choice of pulse sequence parameters, enabling the use of motion‐gated radial stack‐of‐stars MRI in a broader domain of clinical applications.
Large inter-surgeon variability exists in technical anatomical resectability assessment of colorectal cancer liver-only metastases (CRLM) following induction systemic therapy. We evaluated the role ...of tumour biological factors in predicting resectability and (early) recurrence after surgery for initially unresectable CRLM.
482 patients with initially unresectable CRLM from the phase 3 CAIRO5 trial were selected, with two-monthly resectability assessments by a liver expert panel. If no consensus existed among panel surgeons (i.e. same vote for (un)resectability of CRLM), conclusion was based on majority. The association of tumour biological (sidedness, synchronous CRLM, carcinoembryonic antigen and RAS/BRAFV600E mutation status) and technical anatomical factors with consensus among panel surgeons, secondary resectability and early recurrence (<6 months) without curative-intent repeat local treatment was analysed by uni- and pre-specified multivariable logistic regression.
After systemic treatment, 240 (50%) patients received complete local treatment of CRLM of which 75 (31%) patients experienced early recurrence without repeat local treatment. Higher number of CRLM (odds ratio 1.09 95% confidence interval 1.03–1.15) and age (odds ratio 1.03 95% confidence interval 1.00–1.07) were independently associated with early recurrence without repeat local treatment. In 138 (52%) patients, no consensus among panel surgeons was present prior to local treatment. Postoperative outcomes in patients with and without consensus were comparable.
Almost a third of patients selected by an expert panel for secondary CRLM surgery following induction systemic treatment experience an early recurrence only amenable to palliative treatment. Number of CRLM and age, but no tumour biological factors are predictive, suggesting that until there are better biomarkers; resectability assessment remains primarily a technical anatomical decision.
•Role of tumour biological factors in resectability assessment of colorectal cancer liver-only metastases was evaluated.•31% of locally treated patients had early recurrence without repeat local treatment.•Number of colorectal cancer liver-only metastases and age are predictive for early recurrence without repeat local treatment.•Resectability assessment remains primarily a technical anatomical decision.
This study evaluated the relationship between apparent diffusion coefficient (ADC) values in pancreatic ductal adenocarcinoma (PDAC) and tumor grades based on WHO, Adsay, and Kalimuthu ...classifications, using whole-mount pancreatectomy specimens. If glandular formation plays a key role in the degree of diffusion restriction, diffusion-weighted imaging could facilitate non-invasive grading of PDAC. A freehand region of interest (ROI) was drawn along tumor borders on the preoperative ADC map in each tumor-containing slice. Resection specimens were retrospectively graded according to WHO, Adsay, and Kalimuthu classifications and correlated with overall survival and the 10th percentile of whole-volume ADC values. Findings from 40 patients (23 male, median age 67) showed no correlation between ADC p10 values and WHO differentiation (
= 0.050), Adsay grade (
= 0.955), or Kalimuthu patterns (
= 0.117). There was no association between ADC p10 and overall survival (
= 0.082) and other clinicopathological variables. Survival was significantly lower for poor tumor differentiation (
= 0.046) and non-glandular Kalimuthu patterns (
= 0.016) and there was a trend towards inferior survival for Adsay G3 (
= 0.090) after correction for age, tumor location, and stage. Preoperative ADC measurements for determining PDAC aggressiveness had limited clinical utility, as there was no correlation with histological parameters or overall survival in resectable PDAC.
Due to centralization of pancreatic surgery, patients with pancreatic cancer are treated in pancreatic cancer networks, composed of referring hospitals (Spokes) and an expert center (Hub). This study ...aimed to investigate I) how pancreatic cancer networks are organized and II) evaluated by involved clinicians.
Two online surveys were sent out between January–May 2022. Part I (46 questions) was sent out to the surgical network directors of all hospitals of the Dutch Pancreatic Cancer Group (DPCG). Part II (49 questions) was sent out to all involved clinicians in the Hubs-and-Spokes networks.
There was a large variety between the 15 networks concerning number of affiliated Spokes(1-7), annual pancreatoduodenectomies(20-129), and use of a service level agreement (SLA) (40%). More Spoke clinicians considered the Spoke the best location for diagnostic workup (74% vs 36%,P<0.001). While both Spoke (68%) and Hub clinicians (81%) considered attendance of the Spoke at the multidisciplinary team (MDT) meeting as valuable, only 30% of Spoke clinicians attended the MDT frequently. More Hub clinicians thought that exchange of patient information should be improved (37% vs 51%,P=0.005).
A large variety in Dutch pancreatic cancer networks was observed concerning number of affiliated Spokes, use of SLAs, and logistic aspects of network care. Improvement of network care concern agreements on diagnostic workup, use of SLA, Spoke participation in the MDT, and patient information exchange.
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