Four-dimensional MRI using an internal respiratory surrogate derived by dimensionality reduction
| Autor: | Chia-Ho Hua, M Ayaz Khan, Jinsoo Uh |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Adult
Respiratory-Gated Imaging Techniques Percentile 030218 nuclear medicine & medical imaging Scan time Motion 03 medical and health sciences 0302 clinical medicine Image Processing Computer-Assisted medicine Humans Radiology Nuclear Medicine and imaging Simulation Retrospective Studies Mathematics Radiological and Ultrasound Technology medicine.diagnostic_test Phantoms Imaging business.industry Respiration Dimensionality reduction Magnetic resonance imaging Pattern recognition Middle Aged Magnetic Resonance Imaging Healthy Volunteers 030220 oncology & carcinogenesis Female Artificial intelligence business Algorithms |
| Zdroj: | Physics in Medicine and Biology. 61:7812-7832 |
| ISSN: | 1361-6560 0031-9155 |
| DOI: | 10.1088/0031-9155/61/21/7812 |
| Popis: | This study aimed to develop a practical and accurate 4-dimensional (4D) magnetic resonance imaging (MRI) method using a non-navigator, image-based internal respiratory surrogate derived by dimensionality reduction (DR). The use of DR has been previously suggested but not implemented for reconstructing 4D MRI, despite its practical advantages. We compared multiple image-acquisition schemes and refined a retrospective-sorting process to optimally implement a DR-derived surrogate. The comparison included an unconventional scheme that acquires paired slices alternately to mitigate the internal surrogate's dependency on a specific slice location. We introduced 'target-oriented sorting', as opposed to conventional binning, to quantify the coherence in retrospectively sorted images, thereby determining the minimal scan time needed for sufficient coherence. This study focused on evaluating the proposed method using digital phantoms which provided unequivocal gold standard. The evaluation indicated that the DR-based respiratory surrogate is highly accurate: the error in amplitude percentile of the surrogate signal was less than 5% with the optimal scheme. Acquiring alternating paired slices was superior to the conventional scheme of acquiring individual slices; the advantage of the unconventional scheme was more pronounced when a substantial phase shift occurred across slice locations. The analysis of coherence across sorted images confirmed the advantage of higher sampling efficiencies in non-navigator respiratory surrogates. We determined that a scan time of 20 s per imaging slice was sufficient to achieve a mean coherence error of less than 1% for the tested respiratory patterns. The clinical applicability of the proposed 4D MRI has been demonstrated with volunteers and patients. The diaphragm motion in 4D MRI was consistent with that in dynamic 2D imaging which was regarded as the gold standard (difference within 1.8 mm on average). |
| Databáze: | OpenAIRE |
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