Willemijn M. Klein

Radboud University Nijmegen

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Rick R. van Rijn

University of Amsterdam

Mathias Prokop

Radboud University Nijmegen

Lianne J. P. Sonnemans

Radboud University Medical Center

Jos Draaisma

Radboud University Nijmegen

Leo J. Schultze Kool

Radboud University Nijmegen

Bas H. Verhoeven

Radboud University Nijmegen

Desirée H. J. L. M. Koopmanschap

Radboud University Nijmegen

C.J.M. van der Vleuten

Radboud University Medical Center

Owen J. Arthurs

University College London

Ivo de Blaauw

Radboud University Nijmegen

Cooperative Institutions

Radboud University Nijmegen

170

Radboud University Medical Center

163

University Medical Center

108

Radboud Institute for Molecular Life Sciences

University Medical Center Utrecht

Amsterdam University Medical Centers

University of Amsterdam

Utrecht University

Academic Medical Center

Heidelberg University

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Lymphatic Phenotype of Noonan Syndrome: Innovative Diagnosis and Possible Implications for Therapy

Journal of Clinical Medicine (2022)

Lotte E. R. Kleimeier Caroline van Schaik Erika Leenders Maxim Itkin Willemijn M. Klein

Dysregulation of the Ras/Mitogen-activated protein kinase (MAPK) signaling pathway is suggested to play a pivotal role in the development of the lymphatic system in patients with Noonan Syndrome (NS). Pathogenic gene variants in the Ras/MAPK pathway can therefore lead to various lymphatic diseases such as lymphedema, chylo-thorax and protein losing enteropathy. Diagnosis and treatment of the lymphatic phenotype in patients with NS remain difficult due to the variability of clinical presentation, severity and, probably, underlying unknown pathophysiologic mechanism. The objective of this article is to give an overview of the clinical presentation of lymphatic disease in relation to central conducting lymphatic anomalies (CCLA) in NS, including new diagnostic and therapeutic options. We visualized the central conducting lymphatic system using heavily T2-weighted MR imaging (T2 imaging) and Dynamic Contrast-enhanced MR Lymphangiography (DCMRL) and compared these results with the lymphatic clinical presentation in seven patients with NS. Our results show that most patients with NS and lymphatic disease have CCLA. Therefore, it is probable that CCLA is present in all patient with NS, presenting merely with lymphedema, or without sensing lymphatic symptoms at all. T2 imaging and DCMRL can be indicated when CCLA is suspected and this can help to adjust therapeutic interventions.

Noonan Syndrome

Protein losing enteropathy

Lymphangiogenesis

Lymphatic disease

Targeted Therapy

10.3390/jcm11113128

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Citations (9)

Measurement of coronary artery calcium volume using ultra-high-resolution computed tomography: A preliminary phantom and cadaver study

European Journal of Radiology Open (2020)

Wataru Fukumoto Mami Nagaoka Toru Higaki Fuminari Tatsugami Yuko Nakamura

In this phantom- and cadaver study we investigated the differences of coronary artery calcium (CAC) volume on ultra-high-resolution computed tomography (U-HRCT) scans and conventional CT.We scanned a coronary calcium phantom and the coronary arteries of five cadavers using U-HRCT in normal- and super-high resolution (NR, SHR) mode. The NR mode was similar to conventional CT; 896 detector channels, a matrix size of 512, and a slice thickness of 0.5 mm were applied. In SHR mode, we used 1792 detector channels, a matrix size of 1024, and a slice thickness of 0.25 mm. The CAC volume on NR- and SHR images were recorded. Differences in the physical- and the calculated CAC volume were defined as the error value and compared between NR- and SHR images of the phantom. Differences between the CAC volume on NR- and SHR scans of the cadavers were also recorded.The mean error value was lower on SHR- than NR images of the phantom (14.0 %, SD 11.1 vs 20.1 %, SD 15.2, p = 0.01). The mean CAC volume was significantly higher on SHR- than NR images of the cadavers (153.4 mm3, SD 161.0 vs 144.7 mm3, SD 164.8, p < 0.01).As small calcifications were more clearly visualized on U-HRCT images in SHR mode than on conventional (NR) CT scans, SHR imaging may facilitate the accurate quantification of the CAC.

Coronary arteries

10.1016/j.ejro.2020.100253

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Citations (12)

Indications for magnetic resonance imaging of the fetal body (extra-central nervous system): recommendations from the European Society of Paediatric Radiology Fetal Task Force

Pediatric Radiology (2022)

Georgia Papaioannou Pablo Caro‐Domínguez Willemijn M. Klein Cathérine Garel Marie Cassart

Neuroradiology

10.1007/s00247-022-05495-4

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Citations (5)

Imaging and Interventions for Lymphatic and Lymphatic-related Disorders

Radiology (2023)

Jamaal L. Benjamin Cathal O’Leary Saebeom Hur Alexey Gurevich Willemijn M. Klein

The lymphatic system is critical in fluid balance homeostasis. Yet, until recently, lymphatic imaging has been outside of mainstream medicine due to a lack of robust imaging and interventional options. However, during the last 20 years, both clinical lymphatic imaging and interventions have shown dramatic advancement. The key to imaging advancement has been the interstitial delivery of contrast agents through lymphatic-rich tissues. These techniques include intranodal lymphangiography and dynamic contrast-enhanced MR lymphangiography. These methods provide the ability to image and recognize lymphatic anatomy and pathologic conditions. Percutaneous thoracic duct catheterization and embolization became the first widely accepted interventional technique for the management of chyle leaks. Advances in interstitial lymphatic embolization, as well as liver and mesenteric lymphatic interventions, have broadened the scope of possible lymphatic interventions. Also, recent techniques of lymphatic decompression allow for the treatment of a variety of lymphatic disorders. Finally, immunologic studies of central lymphatic fluid reveal the potential of lymphatic interventions on immunity. These advances herald an exciting new chapter for lymphatic imaging and interventions in the coming years. © RSNA, 2023 Supplemental material is available for this article.

10.1148/radiol.220231

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Citations (14)

The radiodensity of cerebrospinal fluid and vitreous humor as indicator of the time since death

Forensic Science Medicine and Pathology (2016)

Desirée H. J. L. M. Koopmanschap A.R. Bayat Bela Kubat Henri M. de Bakker Mathias Prokop

After death, a series of changes occur naturally in the human body in a fairly regular pattern. These postmortem changes are detectable on postmortem CT scans (PMCT) and may be useful in estimating the postmortem interval (PMI). The purpose of our study is to correlate the PMCT radiodensities of the cerebrospinal fluid (CSF) and vitreous humor (VH) to the PMI.Three patient groups were included: group A consisted of 5 donated cadavers, group B, 100 in-hospital deceased patients, and group C, 12 out-of-hospital forensic cadavers. Group A were scanned every hour for a maximum of 36 h postmortem, and the tympanic temperature was measured prior to each scan. Groups B and C were scanned once after death (PMI range 0.2-63.8 h). Radiodensities of the VH and CSF were measured in Hounsfield units. Correlation between density and PMI was determined using linear regression and the influence of temperature was assessed by a multivariate regression model. Results from group A were validated in groups B and C.Group A showed increasing radiodensity of the CSF and VH over time (r (2) CSF, 0.65). PMI overruled the influence of temperature (r = 0.99 and p = 0.000). Groups B and C showed more diversity, with CSF and VH radiodensities below the mean regression line of Group A. The formula of this upper limit indicated the maximum PMI and was correct for >95 % of the cadavers.The results of group A showed a significant correlation between CSF radiodensity and PMI. The radiodensities in groups B and C were higher than in group A, therefore the maximum PMI can be estimated with the upper 95 % confidence interval of the correlation line of group A.

Radiodensity

Hounsfield scale

Group B

Time of death

10.1007/s12024-016-9778-9

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Citations (17)

Correlation Between Liver Volumetric Computed Tomography Results and Measured Liver Weight: A Tool for Preoperative Planning of Liver Transplant.

Experimental and Clinical Transplantation (2016)

Lianne J. P. Sonnemans Jeroen Hol René Monshouwer Mathias Prokop Willemijn M. Klein

Before liver transplant, it is necessary to know the size of the organ in advance of the procedure. We studied the correlation between liver volumetric computed tomography results and liver weight.Postmortem volumetric computed tomography was conducted on cadavers before autopsy, and 3-dimensional liver volume was estimated with semiautomated software. Liver weight was then determined at autopsy. Linear regression and univariate analysis of variance results were used to determine the accuracy of volumetric 3-dimensional computed tomography in estimating liver weight. We also used 2-dimensional liver sizes to design a 2-dimensional formula to estimate liver volume.We found that 3-dimensional volumetric computed tomography was able to accurately estimate liver weight (standard error = 157 g) with a liver density of 0.99 g/mL. Intraobserver and interobserver variabilities were small. The 2-dimensional formula estimated liver weight slightly less accurately (standard error = 212 g).We conclude that liver weight can be estimated accurately with 3-dimensional volumetric computed tomography; estimates were more precise than with the 2-dimensional formula-based liver volume estimation. Volumetric computed tomography can be an important tool during preoperative workup before transplant surgery.

Univariate

10.6002/ect.2015.0142

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Citations (4)

MR Imaging of Neurofluids in the Developing Brain

Neuroimaging Clinics of North America (2025)

Nivedita Agarwal Willemijn M. Klein Ruth Tuura

10.1016/j.nic.2024.12.005

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Citations (0)

Pseudolesion in the right parafissural liver parenchyma on CT: The base is found in embryology and collagen content

PLoS ONE (2020)

Willemijn M. Klein Lianne J. P. Sonnemans Sabine Franckenberg Barbara Fliss Dominic Gascho

Background Computed tomography (CT) images of livers may show a hypo-attenuated structure alongside the falciform ligament, which can be a focal fatty pseudolesion and can mimic a malignancy. The preferred location is on the right parafissural site, ventral in segment IVa/b. The etiology is not clear, nor is it known how the histology of this location develops. These are evaluated in this study. Methods 40 adult cadavers with autopsy and / or postmortem CT in a university hospital and a forensic center were included. Liver biopsies were taken at the left side of the falciform ligament as control, and at the right side as the possible precursor of a pseudolesion; these were examined for collagen and fat content. Cadavers with steatotic (>5% fat) or fibrotic (>2% collagen) control samples were excluded. Results Significantly more collagen was present in the right parafissural liver parenchyma: median 0.68% (IQR: 0.32–1.17%), compared to the left side 0.48% (IQR: 0.21–0.75%) (p 0.008), with equal fat content and CT attenuation values. The etiophysiology goes back to the demise of the umbilical venes in the early embryonic and neonatal period. Conclusions The right parafissural area contains more collagen and an equal amount of fat compared to the control left side. This supports the hypothesis of delayed, ‘third’ inflow: the postnatal change in blood supply from umbilical to portal leaves the downstream parafissural area hypoperfused leading to hypoxia which in turn results in collagen accumulation and the persistence of paraumbilical veins of Sappey.

Falciform ligament

Parenchyma

Liver parenchyma

10.1371/journal.pone.0221544

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Fatal Complications after Pediatric Surgical Interventions: Lessons Learned

European Journal of Pediatric Surgery Reports (2017)

Willemijn M. Klein Mayke Van der Putten Benno Küsters Bas H. Verhoeven

Abstract Placement of catheters, drains, shunts, and tubes in children can lead to serious or even fatal complications at the moment of placement, such as hemorrhage at insertion, or in the longterm, such as infections and migration into adjacent organs. The clinician should always be aware of these potential complications, especially if the child is unwell. For postmortem diagnostic evaluation, either with a computed tomography scan or an invasive autopsy, all tubes, drains, shunts, and/or catheters should be left in situ. We present three cases with fatal complications after the placement of a chest drain, ventriculoperitoneal shunt, and gastrostomy tube.

Gastrostomy tube

10.1055/s-0037-1599795

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Citations (4)

Magnetic resonance imaging measurement of blood volume flow in peripheral arteries in healthy subjects

Journal of Vascular Surgery (2003)

Willemijn M. Klein Lambertus W. Bartels L. Bax Yolanda van der Graaf Willem P.Th.M. Mali

Popliteal artery

10.1016/s0741-5214(03)00706-7

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Citations (47)