Definition	Abbreviation
SR	Super-resolution
CNN	Convolutional neural networks
RFDN	Residual Feature Distillation Network
DRFDCAN	Deep Residual Feature Distillation Channel Attention Network
PSNR	Peak signal-to-noise ratio
MRI	Magnetic Resonance Imaging
CT	Computed Tomography
CAD	Computer-Aided Diagnosis
HR	High-resolution
LR	Low-resolution
SISR	Single Image Super-Resolution
GANs	Generative adversarial networks
ViTs	Vision transformers
RIR	Residual in residual
DRCAB	Residual local feature block
ESA	Enhanced Spatial Attention
RCABs	Residual channel attention network block
RCAN	Residual channel attention networks
LSC	Long skip connections
SSC	Short skip connections
CA	Channel attention
RM	Refinement module
SRB	Shallow residual block
DM	Distillation module
SSIM	Structural similarity index