Evidence map›Paper›PMID 33270997›Full record

ArticleJournal of applied clinical medical physics2020

Retrospective four-dimensional magnetic resonance imaging of liver: Method development.

Henna Kavaluus, Tiina Seppälä, Lauri Koivula, Eero Salli, Juhani Collan, Kauko Saarilahti, Mikko Tenhunen

Open access · goldAbstract read
In one paragraph

Article in Journal of applied clinical medical physics, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
0.3field-weighted citation impact, top 40% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 2 citations in OpenAlex.

  1. Article
  2. Motion modeling from 4D MR images of liver simulating phantom.Journal of applied clinical medical physics · 2022
    Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 3 institutions in 1 country.

Henna KavaluusComprehensive Cancer Center, University of Helsinki and Helsinki University Hospital, Radiotherapy, Finland.
Tiina SeppäläComprehensive Cancer Center, University of Helsinki and Helsinki University Hospital, Radiotherapy, Finland.
Lauri KoivulaComprehensive Cancer Center, University of Helsinki and Helsinki University Hospital, Radiotherapy, Finland.
Eero SalliMedical imaging center, Radiology, University of Helsinki and Helsinki University Hospital, Finland.
Juhani CollanComprehensive Cancer Center, University of Helsinki and Helsinki University Hospital, Radiotherapy, Finland.
Kauko SaarilahtiComprehensive Cancer Center, University of Helsinki and Helsinki University Hospital, Radiotherapy, Finland.
Mikko TenhunenComprehensive Cancer Center, University of Helsinki and Helsinki University Hospital, Radiotherapy, Finland.
University of Helsinki · FIHelsinki Institute of Physics · FIHelsinki University Hospital · FI

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Purpose of our research was to develop a four-dimensional (4D) magnetic resonance imaging (MRI) method of liver. Requirements of the method were to create a clinical procedure with acceptable imaging time and sufficient temporal and spatial accuracy. The method should produce useful planning image sets for stereotactic body radiation therapy delivery both during breath-hold and in free breathing. The purpose of the method was to improve the localization of liver metastasis. The method was validated with phantom tests. Imaging parameters were optimized to create a 4D dataset compressed to one respiratory cycle of the whole liver with clinically reasonable level of image contrast and artifacts. Five healthy volunteers were imaged with T2-weighted SSFSE research sequence. The respiratory surrogate signal was observed by the linear navigator interleaved with the anatomical liver images. The navigator was set on head-feet - direction on the superior surface of the liver to detect the edge of diaphragm. The navigator signal and 2D liver image data were retrospectively processed with a self-developed MATLAB algorithm. A deformable phantom for 4D imaging tests was constructed by combining deformable tissue-equivalent material and a commercial programmable motor unit of the 4D phantom with a clinically relevant range of deformation patterns. 4D Computed Tomography images were used as reference to validate the MRI protocol. The best compromise of reasonable accuracy and imaging time was found with 2D T2-weighted SSFSE imaging sequence using parameters: TR = 500-550 ms, images/slices = 20, slice thickness = 3 mm. Then, image processing with number of respiratory phases = 8 constructed accurate 4D images of liver. We have developed the 4D-MRI method visualizing liver motions three-dimensionally in one representative respiratory cycle. From phantom tests it was found that the spatial agreement to 4D-CT is within 2 mm that is considered sufficient for clinical applications.

Indexed as

Four-Dimensional Computed TomographyMagnetic Resonance ImagingHumansImaging, Three-DimensionalLiverPhantoms, ImagingRespirationRetrospective Studiesliverradiotherapyretrospective 4D-MRISBRT

Identifiers

PMID33270997
PMCPMC7769409
OpenAlexW3110217861

What OpenQuestion holds

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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.