Multiple sclerosis imaging in clinical practice: a European-wide survey of 428 centers and conclusions by the ESNR Working Group

OBJECTIVES

To evaluate compliance with the available recommendations, we assessed the current clinical practice of imaging in the evaluation of multiple sclerosis (MS).

METHODS

An online questionnaire was emailed to all members and affiliates. Information was gathered on applied MR imaging protocols, gadolinium-based contrast agents (GBCA) use and image analysis. We compared the survey results with the Magnetic Resonance Imaging in MS (MAGNIMS) recommendations considered as the reference standard.

RESULTS

A total of 428 entries were received from 44 countries. Of these, 82% of responders were neuroradiologists. 55% performed more than ten scans per week for MS imaging. The systematic use of 3 T is rare (18%). Over 90% follow specific protocol recommendations with 3D FLAIR, T2-weighted and DWI being the most frequently used sequences. Over 50% use SWI at initial diagnosis and 3D gradient-echo T1-weighted imaging is the most used MRI sequence for pre- and post-contrast imaging. Mismatches with recommendations were identified including the use of only one sagittal T2-weighted sequence for spinal cord imaging, the systematic use of GBCA at follow-up (over 30% of institutions), a delay time shorter than 5 min after GBCA administration (25%) and an inadequate follow-up duration in pediatric acute disseminated encephalomyelitis (80%). There is scarce use of automated software to compare images or to assess atrophy (13% and 7%). The proportions do not differ significantly between academic and non-academic institutions.

CONCLUSIONS

While current practice in MS imaging is rather homogeneous across Europe, our survey suggests that recommendations are only partially followed.

CLINICAL RELEVANCE STATEMENT

Hurdles were identified, mainly in the areas of GBCA use, spinal cord imaging, underuse of specific MRI sequences and monitoring strategies. This work will help radiologists to identify the mismatches between their own practices and the recommendations and act upon them.

KEY POINTS

• While current practice in MS imaging is rather homogeneous across Europe, our survey suggests that available recommendations are only partially followed. • Several hurdles have been identified through the survey that mainly lies in the areas of GBCA use, spinal cord imaging, underuse of specific MRI sequences and monitoring strategies.

Diffusion tensor imaging MR neurography in patients with acute or chronic plexopathy

The nerve plexus is susceptible to various pathological processes. In addition to clinical and electrophysiological findings, magnetic resonance neurography (MRN) may contribute to characterize plexus involvement. Diffusion tensor imaging (DTI) was reported feasible for the nerve plexuses imaging but its value in the clinical practice remains uncertain. From 2014 to 2020, we routinely performed MRN including DTI at 3T in patients with acute or chronic plexopathy. DTI images were co-registered with conventional MRN images. MRN images including DTI were reviewed by consensus by two neuroradiologists and one neurologist. They retrospectively identified cases for whom the use of DTI had a potential impact on the diagnostic workup, seven of these clinical cases are presented here. Compared to conventional MRN, the added value of DTI consisted in: (i) improved detection of signal/morphological abnormalities of the plexus (due to removal of background structures, multiplanar reformatted views and large field of view), (ii) additional information regarding the microarchitecture of nerve fibers provided by DTI metrics, (iii) potential alternative for the use of gadolinium. This case series supports the implementation of DTI in MRN protocols.

[Therapeutic and endovascular management of cerebral mycotic aneurysms]

Infective endocardites are associated with both ischemic and hemorrhagic neurological complications and also with cerebral abscesses and the development of "mycotic" aneurysms, which are detected in about 5 % of patients in the acute and sub-acute phase of the infection. Data about their natural history and their hemorrhagic risk are scarce and fragmented. The therapeutic management is represented by the medical treatment of the infection with interventional abstention, the surgical treatment and the endovascular approach by selective embolization of the aneurysm. No evidence is provided concerning the superiority of a specific approach. Mycotic aneurysms remain a diagnostic and therapeutic challenge and their management is necessarily based on a multidiscplinary approach.

Unusual Brain MRI Pattern in 2 Patients with COVID-19 Acute Respiratory Distress Syndrome

We report the cases of 2 patients hospitalized in our intensive care unit with confirmed coronavirus disease 2019 infection in whom brain MR imaging showed an unusual DWI pattern with nodular and ring-shaped lesions involving the periventricular and deep white matter. We discuss the possible reasons for these findings and their relationship to the infection.

Breath-hold compressed-sensing 3D MR cholangiopancreatography compared to free-breathing 3D MR cholangiopancreatography: prospective study of image quality and diagnostic performance in pancreatic disorders

PURPOSE

To compare image quality and diagnostic performance of three magnetic resonance cholangiopancreatography (MRCP) protocols in patients with suspected pancreatic abnormalities: free-breathing standard 3D-MRCP (STD), free-breathing compressed sensing 3D-MRCP (CS), and CS 3D-MRCP with acquisition during a single breath-hold > 20 s (BH-CS).

METHODS

Informed consent was obtained. We performed 57 MRCPs in 56 prospectively included patients (29 men, median age 59 years). The three protocols were performed in random order. Acquisition time was recorded. Two radiologists blinded to the protocols used 5-point scales to assess image quality parameters (overall image quality, amount of artifacts, background suppression, bile and pancreatic duct visualization) and diagnostic performance (anatomical variants, duct abnormalities, cystic lesions).

RESULTS

Acquisition time was 279 s with STD, 176 s with CS (-37%), and 22 s with BH-CS (-93%). STD and BH-CS were not significantly different for overall image quality, artifacts, or background suppression. The BH-CS group had fewer non-diagnostic scans (3% vs. 19% with STD and 21% with CS, p < 0.05), higher-quality scans (78% vs. 66% with STD and 58% with CS, p < 0.05), and milder artifacts (2% vs. 18% with STD and 16% with CS, p < 0.05). The main pancreatic duct was better visualized with BH-CS compared to STD (p = 0.015) and CS (p < 0.001). Diagnostic performance did not differ across the three protocols. There were fewer indeterminate scans in the BH-CS group.

CONCLUSION

3T BH-CS is reliable, saves time, and is not associated with decreases in image quality or diagnostic performance compared to STD and CS.