Mapping prostatic microscopic anisotropy using linear and spherical b-tensor encoding: A preliminary study.
Magn Reson Med
; 86(4): 2025-2033, 2021 10.
Article
em En
| MEDLINE
| ID: mdl-34056750
ABSTRACT
PURPOSE:
Tensor-valued diffusion encoding provides more specific information than conventional diffusion-weighted imaging (DWI), but has mainly been applied in neuroimaging studies. This study aimed to assess its potential for the imaging of prostate cancer (PCa).METHODS:
Seventeen patients with histologically proven PCa were enrolled. DWI of the prostate was performed with linear and spherical tensor encoding using a maximal b-value of 1.5 ms/µm2 and a voxel size of 3 × 3 × 4 mm3 . The gamma-distribution model was used to estimate the mean diffusivity (MD), the isotropic kurtosis (MKI ), and the anisotropic kurtosis (MKA ). Regions of interest were placed in MR-defined cancerous tissues, as well as in apparently healthy tissues in the peripheral and transitional zones (PZs and TZs).RESULTS:
DWI with linear and spherical encoding yielded different image contrasts at high b-values, which enabled the estimation of MKA and MKI . Compared with healthy tissue (PZs and TZs combined) the cancers displayed a significantly lower MD (P < .05), higher MKI (P < 10-5 ), and lower MKA (P < .05). Compared with the TZ, tissue in the PZ showed lower MD (P < 10-3 ) and higher MKA (P < 10-3 ). No significant differences were found between cancers of different Gleason scores, possibly because of the limited sample size.CONCLUSION:
Tensor-valued diffusion encoding enabled mapping of MKA and MKI in the prostate. The elevated MKI in PCa compared with normal tissues suggests an elevated heterogeneity in the cancers. Increased in-plane resolution could improve tumor delineation in future studies.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Próstata
/
Neoplasias da Próstata
Tipo de estudo:
Prognostic_studies
Limite:
Humans
/
Male
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article